FORM -1 ENVIRONMENTAL CLEARANCE FOR COPPER SMELTER PLANT –II FOR PRODUCING 1200 TPD COPPER AT SIPCOT INDUSTRIAL COMPLEX, THERKKU VEERAPANDIAPURAM VILLAGE, OTTAPIDARAM TALUK, THOOTHUKKUDI, TAMILNADU

Submitted to:

Ministry of Environment, Forests and Climate Change New Delhi

Submitted by: Vedanta Ltd., Copper Smelter Plant -II Thoothukudi.

January, 2018

Form -1 FORM 1 (I) Basic Information

S.No. Item Details 1. Name of the Project/s Vedanta Ltd., Copper Smelter Plant -II (1200 TPD Copper) 2. S. No. in the schedule Category A: 3(a) Primary metallurgical industry. 3. Proposed capacity / area / S. Plant –II Products length / tonnage to be No. units in TPD handled / command area I Main Products / lease area / number of 1 Copper Anode 1200 wells to be drilled 2 Copper Cathode 1525 (from anodes produced) 3 Continuous Copper Rod 800 (from cathodes produced) 4 Phosphoric Acid 800 II Intermediate Products 5 Anode slime (refinery) 3 6 Dore Anode 0.65 (from Anode Slime produced) 7 Selenium 1.2 (from Anode Slime produced) 8 Bismuth Bi sulphate 1.8 (from foul Electrolyte produced) 9 Copper telluride 0.6 (from foul Electrolyte produced) 10 Nickel sludge (from foul 30 Electrolyte produced) 11 Nickel (from foul 1.5 Electrolyte produced) III By-Products 12 Sulphuric Acid 4800* 13 Ferro sand 3000 14 Gypsum 4200 15 Hydrofluro-Silicic Acid 80

* - Sulphuric Acid Plant will be designed for 5900 TPD considering the extreme case scenario of sulphur content in the Copper Concentrate.

S.No. Item Details 4. New / Expansion / New Plant Modernization 5. Existing Capacity / Area Not applicable etc 6. Category of Project i.e. ‘A’ Category-A: 3(a) Primary metallurgical or ‘B’ industry. 7. Does it attract the general Not applicable condition? If yes, please specify. 8. Does it attract the specific Not applicable condition? If yes, please specify. 9. Location Copper Smelter Plant – II will be located at SIPCOT Industrial Complex, Therkku Veerapandia Puram Village in Thoothukudi.

Latitude & Longitude:

Northwest-08°50’29.9”N 78°04’12.9”E Southwest-08°49’45.3”N 78°04’05”E Southeast-08°49’32.9”N 78°04’40.7”E Northeast-08°49’58.8”N 78°04’47.8”E

Plot / Survey / Khasra No. Survey Numbers are referred in Annexure - 1 Village Therku Veera Pandia Puram Tehsil Ottapidaram. District Thoothukudi State Tamil Nadu 10. Nearest railway station / Meelavittan (2.0-km, SE) airport along with distance in kms. 11. Nearest Town, City, Thoothukkudi (8.4-km, ESE) District Headquarters along with distance in kms. 12. Village Panchayats, Zilla Therku Veera Pandia Puram Village Panchayat Parishad, Municipal Ottapidaram Taluk. Corporation, Local body Thoothukudi District (complete postal Thoothukudi – 628002. addresses with telephone nos. to be given) 13. Name of the applicant Vedanta Ltd., Copper Smelter Plant -II (1200 TPD Copper) 14. Registered Address 1st Floor, ‘C’ Wing, Unit 103, Corporate Avenue, Atul Projects, Chakala, Andheri (E), Mumbai – 400 093 15. Address for Sterlite Copper (A unit of Vedanta Limited), correspondence : SIPCOT Industrial Complex, Madurai Bypass Road, Thoothukudi – 628002 Tamilnadu

S.No. Item Details Name P.Ramnath Designation Chief Executive Officer, (Owner/Partner/CEO) Vedanta Ltd., Copper Smelter Plant -II Address Copper Smelter Plant – II (1200 TPD Copper) SIPCOT Industrial Complex, Therkku Veerapandia Puram Village, Thoothukudi. Pin Code 628002 Email [email protected] Telephone No. 0461 – 4242222 Fax No. 0461 – 4242047 16. Details of Alternative Sites Copper Smelter Project -II is under examined, if any. Location construction as per EC F.No. J- of these sites should be 11011/431/2008-IA II (I) dated 01st shown on a topo sheet. January 2009 valid up to 31.12.2018. Hence alternative sites are not examined. 17. Interlinked Projects Not applicable 18. Whether separate Not applicable application of interlinked project has been submitted? 19. If yes, date of submission Not applicable 20. If no, reason Not applicable 21. Whether the proposal Not applicable involves approval/clearance under: if yes, details of the same and their status to be given. (a) The Forest (Conservation) Act, 1980? (b) The Wildlife (Protection) Act, 1972? (c) The C.R.Z Notification, 1991? 22. Whether there is any Not applicable Government Order/Policy relevant/relating to the site? 23. Forest land involved Not applicable (hectares) 24. Whether there is any Not applicable litigation pending against the project and/or land in which the project is propose to be set up? (a) Name of the Court (b) Case No. (c) Orders/directions of the Court, if any and its relevance with the proposed project.

(II) Activity

1. Construction, operation or decommissioning of the Project involving actions, which will cause physical changes in the locality (topography, land use, changes in water bodies, etc.)

Details thereof (with approximate quantities Information/Checklist Yes/ S.No. /rates, wherever possible) confirmation No with source of information data 1.1 Permanent or temporary change in No This Copper Smelter Plant II land use, land cover or topography land site is developed by including increase in intensity of State Industries Promotion land use (with respect to local Corporation of Tamil Nadu land use plan) Limited, (SIPCOT), Government of Tamilnadu. 1.2 Clearance of existing land, No Not applicable vegetation and buildings? 1.3 Creation of new land uses? No Not applicable 1.4 Pre-construction investigations e.g. Yes Pre-construction bore houses, soil testing? investigations were completed and construction is in progress. 1.5 Construction works? Yes The units like ISA Furnace - Smelter, H2SO4 plant, Phosphoric Acid Plant, Copper Refinery, Continuous Copper rod plant and minor/precious metal recovery plant etc are being constructed as per EC F.No. J-11011/431/2008- IA II (I) dated 01st January 2009 valid up to 31.12.2018. 1.6 Demolition works? No Not envisaged, since it is green field project. 1.7 Temporary sites used for No Contractor offices, housing construction works or housing of facilities and canteen construction workers? facilities are provided for construction workers. 1.8 Above ground buildings, structures Yes Above ground buildings, or earthworks including linear structures and earthworks structures, cut and fill or excavations are there. 1.9 Underground works including mining No Not envisaged. or tunneling? 1.10 Reclamation works? No Not envisaged 1.11 Dredging? No Not envisaged 1.12 Offshore structures? No Not envisaged 1.13 Production and manufacturing Yes Enclosed as Annexure –1 processes? 1.14 Facilities for storage of goods or Yes Material stock yard are materials? provided in the proposed project.

1.15 Facilities for treatment or disposal of Yes Enclosed as Annexure -2 solid waste or liquid effluents? 1.16 Facilities for long term housing of No Housing colony already operational workers? exists. 1.17 New road, rail or sea traffic during Yes Approach road has been construction or operation? provided and Material conveying shall be planned from the railway siding for material movement. 1.18 New road, rail, air waterborne or Yes Approach road has been other transport infrastructure provided. Our Railway including new or altered routes and siding in Meelavittan will be stations, ports, airports etc? utilized to transport raw materials and products during plant operation. 1.19 Closure or diversion of existing No Not envisaged transport routes or infrastructure leading to changes in traffic movements? 1.20 New or diverted transmission lines No Not envisaged or pipelines? 1.21 Impoundment, damming, culverting, Yes Natural Nullah used for rain realignment or other changes to the water drainage will be hydrology of watercourses or reoriented. aquifers? 1.22 Stream crossings? Yes Natural Nullah used for rain water drainage will be reoriented.

1.23 Abstraction or transfers of water No Not envisaged. form ground or surface waters? 1.24 Changes in water bodies or the land Yes Natural Nullah used for rain surface affecting drainage or run- water drainage will be off? reoriented. 1.25 Transport of personnel or materials Yes Approach road has been for construction, operation or provided. decommissioning? 1.26 Long-term dismantling or No Not applicable decommissioning or restoration works? 1.27 Ongoing activity during No Not applicable decommissioning which could have an impact on the environment? 1.28 Influx of people to an area in either No Not envisaged temporarily or permanently? 1.29 Introduction of alien species? No Not envisaged 1.30 Loss of native species or genetic No Not envisaged diversity? 1.31 Any other actions? No Not envisaged

2. Use of Natural resources for construction or operation of the Project (such as land, water, materials or energy, especially any resources which are non-renewable or in short supply):

Details thereof (with Information/checklist Yes/ approximate quantities /rates, S.No. confirmation No wherever possible) with source of information data Land especially undeveloped or No This Copper Smelter Plant – II 2.1 agricultural land (ha) land site is developed in State Industries Promotion Corporation of Tamil Nadu Limited, (SIPCOT) Industrial Area, Government of Tamilnadu. Yes Fresh raw water requirement 2.2 Water (expected source & competing for proposed Copper users) unit: KLD Smelter Plant -II is about 8773 KLD. Already Vedanta Ltd., has approval from SIPCOT for 4.16 MGD water supply (Enclosed as Annexure-3) and the unit is using 2 MGD for the existing operation.

Hence, additional Water supply for the Copper Smelter –II will be sourced from SIPCOT, Desalination plant / Municipal Sewage water treatment. Yes Enclosed as Annexure-4 2.3 Minerals (MT) Yes Construction material are 2.4 Construction material – stone, sourced from government aggregates, sand / soil (expected source – MT) approved quarries. The Estimated Quantity of construction material is detailed below: Stone : 10000 MT Aggregates : 24000 MT Sand / Soil : 72000 MT Yes Timber : 600 MT 2.5 Forests and timber (source – MT) Yes Enclosed as Annexure-5 2.6 Energy including electricity and fuels (source, competing users) Unit: fuel (MT), energy (MW) No Not envisaged 2.7 Any other natural resources (use appropriate standard units)

3. Use, storage, transport, handling or production of substances or materials, which could be harmful to human health or the environment or raise concerns about actual or perceived risks to human health.

Details thereof (with approximate quantities Information/Checklist Yes/ S.No. /rates, wherever possible) confirmation No with source of information data 3.1 Use of substances or materials, Yes Enclosed as Annexure-6 which are hazardous (as per MSIHC rules) to human health or the environment (flora, fauna, and water supplies) 3.2 Changes in occurrence of disease or No Not envisaged affect disease vectors (e.g. insect or water borne diseases) 3.3 Affect the welfare of people e.g. by No Direct and indirect changing living conditions? employment avenues are created due to project and the living conditions of people are continuously improved through socio-economic measures by proponent. More employment avenues and ancillary developments will be created in this industrially backward region and will benefit the society at large. 3.4 Vulnerable groups of people who No Not applicable could be affected by the project e.g. hospital patients, children, the elderly etc., 3.5 Any other causes No Not applicable

4. Production of solid wastes during construction or operation or decommissioning (MT/month)

Details thereof (with approximate quantities Information/Checklist Yes/ S.No. /rates, wherever possible) confirmation No with source of information data 4.1 Spoil, overburden or mine wastes. No The spoil generated during construction will be reused for construction as well as for filling. 4.2 Municipal waste (domestic and or Yes About 0.4 TPD of garbage commercial wastes) generation is envisaged from the proposed plant. 4.3 Hazardous wastes (as per Hazardous Yes Enclosed as Annexure-2 Waste Management Rules)

4.4 Other industrial process wastes Yes Enclosed as Annexure-2 4.5 Surplus product No 4.6 Sewage sludge or other sludge from Yes Enclosed as Annexure-2 effluent treatment 4.7 Construction or demolition wastes No Packing material are the envisaged constructional wastes. However, no major constructional solid waste is generated 4.8 Redundant machinery or equipment No Not envisaged 4.9 Contaminated soils or other No Not envisaged materials 4.10 Agricultural wastes No Not envisaged 4.11 Other solid wastes No Not envisaged

5. Release of pollutants or any hazardous, toxic or noxious substances to air (Kg/hr)

Details thereof (with approximate quantities Information/Checklist Yes/ S.No. /rates, wherever possible) confirmation No with source of information data 5.1 Emissions from combustion of fossil Yes Exhaust emissions from fuels from stationary or mobile vehicles and equipment sources deployed during the construction and operational phases result in marginal emissions of SO2, NOx and CO. Periodical vehicles maintenance of vehicles and vehicle pollution check are being ensured. 5.2 Emissions from production processes Yes Well within the limits as prescribed by the MoEF&CC emission norms. Stack Emission details is enclosed as Annexure-7 5.3 Emissions from materials handling Yes Exhaust emissions from including storage or transport vehicles and equipment deployed during the construction and operational phases result in marginal emissions of SO2, NOx and CO. Periodical vehicles maintenance of vehicles and vehicle pollution check are being ensured. Water sprinkling are being regularly carried out to control dust emission. 5.4 Emissions from construction Yes Exhaust emissions from activities including plant and vehicles and equipment equipment deployed during the construction result in marginal emissions of SO2, NOx and CO.

5.5 Dust or odours from handling of Yes Dust emission are being materials including construction controlled by water materials, sewage and waste sprinkling. 5.6 Emissions from incineration of waste Yes Emission from incinerator is controlled by dispersion through chimney. 5.7 Emissions from burning of waste in No Not envisaged open air (e.g. slash materials, construction debris) 5.8 Emissions from any other sources No Not envisaged

6. Generation of Noise and Vibration, and Emissions of Light and Heat:

Details thereof (with approximate quantities Information/Checklist Yes/ /rates, wherever possible) S.No. confirmation No with source of information data with source of information data 6.1 From operation of equipment e.g. Yes Proper Noise, Vibration and engines, ventilation plant, crushers Heat arrester are being provided at the generation point itself. Proper work place will be maintained for operational employees. 6.2 From industrial or similar processes Yes Proper Noise, Vibration and Heat arrester are being provided at the generation point itself. Proper work place will be maintained for operational employees. 6.3 From construction or demolition No The constructional noise are in the range of about 65-80 dB(A). Regular maintenance of the constructional equipment helps in reducing these noise levels further. 6.4 From blasting or piling No Not envisaged 6.5 From construction or operational Yes The constructional noise are traffic in the range of about 65-80 dB(A).

About 80 dB(A) noise is envisaged from the traffic during operational phases 6.6 From lighting or cooling systems No Not Applicable 6.7 From any other sources No Not Applicable

7. Risks of contamination of land or water from releases of pollutants into the ground or into sewers, surface waters, groundwater, coastal waters or the sea:

Details thereof (with approximate quantities Information/Checklist Yes/ S.No. /rates, wherever possible) confirmation No with source of information data 7.1 From handling, storage, use or No The expected list of haz. spillage of hazardous materials waste generated from the process and handling are detailed in Annexure – 2 7.2 From discharge of sewage or other No 100 m3 of treated sewage effluents to water or the land effluent from Sewage (expected mode and place of Treatment plant will be used discharge) back to the Green Belt. 7.3 By deposition of pollutants emitted No The incremental ground level to air into the land or into water concentrations of air pollutants (dust) are likely to be well within the permissible limits. Hence, no impact on air is envisaged. 7.4 From any other sources No Not envisaged 7.5 Is there a risk of long term build up No Not envisaged of pollutants in the environment from these sources?

8. Risk of accidents during construction or operation of the Project, which could affect human health or the environment

Details thereof (with approximate quantities Information/Checklist Yes/ S.No. /rates, wherever possible) confirmation No with source of information data 8.1 From explosions, spillages, fires etc No from storage, handling, use or production of hazardous substances 8.2 From any other causes No 8.3 Could the project be affected by No The project is located in natural disasters causing seismically stable zone environmental damage (e.g. floods, earthquakes, landslides, cloudburst etc)?

9. Factors which should be considered (such as consequential development) which could lead to environmental effects or the potential for cumulative impacts with other existing or planned activities in the locality

Details thereof (with approximate quantities Information/Checklist Yes/ S. No. /rates, wherever possible) confirmation No with source of information data 9.1 Lead to development of supporting, Yes Proposed Project will result facilities, ancillary development or in considerable growth of development stimulated by the service sector and also project which could have impact on generates new industrial and the environment e.g.: business opportunities in the  Supporting infrastructure (roads, area. power supply, waste or waste During operational phase, water treatment, etc.) Vedanta Ltd., require  housing development significant workforce of non-  extractive industries technical and technical  supply industries persons. This will increase  other the employment opportunities in the region. 9.2 Lead to after-use of the site, which No could have an impact on the environment 9.3 Set a precedent for later No developments 9.4 Have cumulative effects due to No proximity to other existing or planned projects with similar effects

(III) Environmental Sensitivity

Aerial distance (within Name/ 15 km.) Proposed S.No. Areas Identity project location boundary 1 Areas protected under international Islands in 13.5-km, NE direction conventions, national or local Gulf of legislation for their ecological, Mannar landscape, cultural or other related value 2 Areas which are important or Islands in 13.5-km, NE direction sensitive for ecological reasons - Gulf of Wetlands, watercourses or other Mannar water bodies, coastal zone, biospheres, mountains, forests 3 Areas used by protected, important Islands in 13.5-km, NE direction or sensitive species of flora or fauna Gulf of for breeding, nesting, foraging, Mannar resting, over wintering, migration 4 Inland, coastal, marine or Bay of 9.5-km , NE and E underground waters Bengal 5 State, National boundaries Nil Not Applicable 6 Routes or facilities used by the public Nil Not Applicable for access to recreation or other tourist, pilgrim areas 7 Defence installations Nil Not Applicable 8 Densely populated or built-up area Thoothu 6.4-km-ESE kudi 9 Areas occupied by sensitive man- Schools, Within 15-km radius in made land uses (hospitals, Colleges, Thoothukudi. schools, places of worship, Hospitals, community facilities) Places of worship. 10 Areas containing important, high No quality or scarce resources(ground water resources, surface resources, forestry, agriculture, fisheries, tourism, minerals) 11 Areas already subjected to pollution No Not applicable or environmental damage. (those where existing legal environmental standards are exceeded)

12 Areas susceptible to natural hazard No Not applicable which could cause the project to present environmental problems (earthquakes, subsidence, landslides, erosion, flooding or extreme or adverse climatic conditions)

Annexure-1

Pre Feasibility study of Copper Smelter –II

ANNEXURE-I

1.0 INTRODUCTION

About the Company

Vedanta Ltd., is a group company of Vedanta Resources Plc.London. Vedanta Limited is one of the world’s largest diversified natural resource companies listed on BSE, NSE and NYSE. Vedanta Ltd., produce copper, zinc, lead, silver, aluminium, iron ore, oil & gas and commercial power and have a presence across India, South Africa, Namibia, Ireland, Australia, Liberia and Sri Lanka. Sustainability is at the core of Vedanta’s strategy, with a strong focus on health, safety and environment and on enhancing the lives of local communities.

Vedanta Ltd., has a strong track record in managing operations and improving costs and output. Indian zinc and copper operations rank in its top quartile of global cost efficiency.

Vedanta Ltd., is the first company in India to set up a Copper Smelter and Refinery in private sector and operate the largest capacity continuous Cast Copper Rod plants. The main products are Copper Anodes, Cathodes and Rods, which meet global quality benchmarks.

Project Background

The first integrated copper Smelter -I complex at Thoothukudi was commissioned for commercial production during 1997. The company owns copper mines in Australia and remaining requirements of copper concentrate is imported from Chile, South America, Australia and Indonesia.

The proposed Copper Smelter –II project is a green field project.

Production Capacity

The production capacity of Copper Smelter Plant –II is presented in Table-1.

TABLE-1

DETAILS OF PRODUCTION CAPACITY

S.No Products Units Plant –II . I Main Products 1 Copper Anode TPD 1200 2 Copper Cathode TPD 1525 (from anodes produced) 3 Continuous Copper Rod TPD 800 (from cathodes produced) 4 Phosphoric Acid TPD 800 II 5 Anode slime (refinery) TPD 3.0 6 Dore Metal TPD 0.650 (from Anode Slime produced) 7 Selenium TPD 1.200 (from Anode Slime produced) 8 Bismuth Bi sulphate TPD 1.800 (from foul Electrolyte produced) 9 Copper telluride TPD 0.600 (from foul Electrolyte produced) 10 Nickel sludge (from foul Electrolyte TPD 30 produced) 11 Nickel (from foul Electrolyte produced) TPD 1.500

III By-Products 12 Sulphuric Acid TPD 4800** 13 Ferro sand TPD 3000 14 Gypsum TPD 4200 15 Hydrofluro-Silicic Acid TPD 80

** - Sulphuric Acid Plant will be designed for 5900 TPD considering the extreme case scenario of sulphur content in the Copper Concentrate.

Significance of the Project

Copper application areas covers wide varieties of different disciplines like, Architectural, Electrical, Automotive, Tube, Pipe, Fuel gas, Industrial, Marine and Machine products which gives a great demand.

Copper is a strategic metal for development of industry in India. It is considered to be the third most important industrial metal next only to iron and aluminium. Combination of its excellent properties such as high electrical and thermal conductivity, high strength, malleability, easy workability, corrosion resistance and its ability to produce alloys with other metals in an attractive range of colours has made copper a strategic metal for the engineering industry. Specific applications of copper include power cables and wires, jelly filled cables, building wires, air conditioning and refrigeration tubing, Telecom, Power, Construction, Transportation, Handicrafts, Engineering, Consumer Durable, Defence, etc. With Indian economy poised for growth, development in infrastructure and power sector will lead to demand of copper. The per capita consumption of copper in India is only in the range of 0.5 kg, when compared to China’s per capita consumption of approx. 4.6 kg and world average of 2.4kg. (Source: Ministry of Mines, Govt. of India). Prior to setting up of the Copper Smelter at Thoothukudi by the Company (Vedanta Ltd.,), the country was a net importer of Copper. Post setting up of the copper smelter by the Company, the country is able to earn valuable foreign exchange and hence improves the Current Account Deficit.

Description of Plant Site

Copper Smelter Plant -II is located in the SIPCOT Industrial Complex, Therkku Veerapandia Puram Village, Thoothukudi. The Total area earmarked for is 128.805 Hectare of land allotted by State Industries Promotion Corporation of Tamil Nadu Limited, (SIPCOT), a Government of Tamilnadu undertaking specially for promoting industrial development.

State Industries Promotion Corporation of Tamil Nadu Limited ('SIPCOT') handed over land of 131.3 ha for 1200 TPD Copper smelter Plant – II. SIPCOT and executed three lease deeds, one, dated 16-02-2009 (for 36.16 hectares of land), the second, dated 07-10-2009 (for 93.33 hectares of land) and the third dated 03-06-2010 (for 1.84 hectres) in favour of the Company at SIPCOT Industrial Complex, Thoothukudi and handed over the land as per lease agreements to the Company.

Copper Smelter –II will be located in 128.805 ha. and the Land kept in hand in Zone –A for future purpose is 2.585 ha.

The location map and study area of 10-km radius of the plant is shown in Figure-1 and Figure-2 respectively.

Environmental Setting of the Plant Site

The environmental setting of the plant site is given in Table-2. TABLE-2 ENVIRONMENTAL SETTING OF THE PLANT SITE (10-KM RADIUS)

Sr. Particulars Details No. 1 Latitude Northwest-08o50’29.9”N 78o04’12.9”E Southwest-08o49’45.3”N 78o04’05”E Southeast-08o49’32.9”N 78o04’40.7”E Northeast-08o49’58.8”N 78o04’47.8”E 2 Elevation above MSL 20-m above Mean Sea Level 3 Climatic conditions As per IMD Thoothukkudi: Annual Mean Max Temp : 38.3o C Annual Mean Min Temp : 19.4o C Average Annual Total Rainfall :625.8 mm 4 Present land use Industrial Area 5 Nearest Highway NH-45B Connecting Madurai and Thoothukkudi (1.5-km, SE) 6 Nearest Railway Station Milavittan (2.0-km, SE) 7 Nearest Airport Vaagaikulam (12-km, W) 8 Nearest Town/City Thoothukkudi (8.4-km, ESE) 9 Hills/valleys Nil within 10-km radius 10 Archaeologically important Nil within 10-km radius places 11 National Parks/ Wildlife Nil within 10-km radius; Sanctuaries 12 Reserved / Protected Nil within 10-km radius Forest 13 Seismicity Zone-II 14 Streams/Rivers No major rivers within 15-km radius 15 Defence Installations Nil within 15-km radius 16 Port Thoothukudi Port (17-km) 17 List of Industries within 7- 1. M/s VV. Titanium Pigments Pvt. Ltd, km radius Thoothukudi 2. M/s. Tuticorin Spinning Mill 3. Small scale industries in SIPCOT 4. Ind Bharath Power Plants

FIGURE-1 LOCATION MAP OF THE PLANT

FIGURE-2 STUDY AREA MAP (10-KM RADIUS)

Infrastructure Facility

The SIPCOT industrial complex is fully developed industrial estate provided with all types of infrastructure facilities such as road, rail and goods yard, water supply drainage etc. The SIPCOT area is well connected by road and rail. Power is readily available through separate sub-stations. Thoothukudi port is located at a distance of 17-km, which provides additional advantage and facilities for import and export of materials required by the industries in the region.

1.1. Smelter Operation

The copper anodes are produced from the imported copper concentrate through pyro-metallurgical (smelting) processes. The sulphur dioxide generated during the smelting of copper is converted into sulphuric acid by Double Conversion Double Absorption (DCDA) process. A part of this sulphuric acid is captively utilized for production of phosphoric acid from the imported rock phosphate using a Hemi-hydrate-Di-hydrate process. The copper anodes are next dispatched to the refinery unit for further electrolytic refining to about 99.99% purity, which is necessary to obtain the required electrical conductivity for electrical applications.

The principal raw material for the production of copper metal at Vedanta Ltd., is copper concentrate containing about 25-35% copper, 25-32% sulphur, iron 25- 30% and 7-10% moisture. The major steps in copper extraction include:

 Blending of different grades of concentrates;

 Smelting of concentrates in ISASMELT furnace to produce an intermediate copper rich product known as ‘matte’ containing 60-65% copper and eliminate iron as iron silicate (Ferro Sand) by adding silica;

 Converting liquid matte to blister copper (98-99% Cu) in Pierce-Smith converters (PS converters);

 Fire refining of blister copper to produce anode copper (99.5% Cu) in anode furnace and casting of the anodes; and

 Electrolytic refining of anodes to produce copper cathodes (99.99% Cu).

In the process of extraction of copper metal from copper concentrates, sulphuric acid is recovered as a by-product from the sulphur dioxide emanating from the ISASMELT and PS converting furnaces.

1.2 Brief Process Description - Smelter Plant

ISASMELT is an established, novel pyro-metallurgical bath smelting process for the extraction of copper from copper concentrates. The process comprises of smelting the copper concentrate in a vertical, cylindrical, refractory brick lined, flat roofed furnace vessel. A central lance injects air, oxygen and fuel into the molten bath of ferro sand and the matte. The oxygen enriched air and fuel down the lance violently stirs the liquid vigorously. These lances are the proprietary supply of the technology supplier. These lances are a ‘pipe within pipe’ assembly. They are constructed from a composite of stainless and mild steel and incorporate specially designed helical gas swivel that enables the use of low-pressure air and oxygen. Controlled swiveling of the process gases inside the lance cools the outer section sufficiently to solidify a layer of ferro sand around the outer surface of the lance. This provides a protective coating in the highly aggressive bath environment.

The lance goes through the top of the furnace into the bath and the SO2 off-gases from the furnace pass up through an uptake shaft to a waste heat recovery boiler (WHRB) and the gases pass through an electrostatic precipitator for the removal of the dust before the gases are conveyed to the sulphuric acid plant.

The products of the ISASMELT process, matte and ferro sand are tapped periodically from the bottom of the furnace through a water-cooled copper tap hole. The matte and ferro sand then flow into a Rotary Holding Furnace (RHF) where the matte separates from the ferro sand due to density. The ferro sand from the rotary holding furnace / Ferro sand cleaning furnace is granulated in a dedicated ferro sand granulation system and the granulated ferro sand is discarded to a place inside the smelter plot for beneficial applications.

The matte (63±3% Cu) is conveyed through ladles to Pierce Smith (PS) Converters for conversion to blister copper by blowing process air into the bath through tuyeres. The SO2 off gases from the PS converter is passed through an ESP for the removal of residual dust before being led to acid plant for the production of sulphuric acid.

The blister copper is further treated in anode furnaces by fire refining and cast into anodes for electro-refining in an ISA REFINERY to a saleable copper cathode of 99.99% Cu purity.

1.2.1 Operational Theory of Smelter

The copper concentrate is selectively oxidized in the bath of the ISASMELT furnace in such a way to liberate part of SO2 and the exothermic heat from

reactions inside the furnace raises the temperature of the constituents above their melting point. The instantaneous smelting reaction forms molten mass of Cu2S, FeS, FeO and Fe304. Further reaction takes place in the molten mass where FeO reacts with the silica in the charge to form ferro sand. Two separate liquid phases are formed in the rotary holding furnace.

After the removal of ferro sand by granulation, molten matte from the RHF furnace containing about 63±3% copper is poured from the RHF at about 1200oC into ladles and six ladles of 10m3 are transferred through EOT cranes to the Pierce-Smith converter. In converter, air is blown to the liquid matte at 150 kPa pressure through side-blown tuyeres, and quartz added as a flux in three stages results in production of the blister copper. The operation of converter is autogenous and exothermic; the heat of reactions is more than sufficient to maintain the operating temperatures. The products from converter are blister copper (about 98.5% Cu) and ferro sand (approx. 5-7% Cu).

The ferro sand from the converters is cleaned in a ferro sand cleaning furnace for reducing copper in discard ferro sand. The ferro sand is allowed to settle in ferro sand cleaning furnace where again two layers of molten matte and ferro sand are formed. Matte from ferro sand cleaning furnace is treated in converters whereas ferro sand is granulated and discarded. The off gases from ISASMELT furnace and converters after cleaning and cooling are utilized for the production of sulphuric acid. Blister copper poured from converter to ladles is transferred to anode furnaces by means of EOT cranes for further fire refining. Controlled air blow first oxidizes remaining sulphur to remove as sulphur dioxide. However in the process, part of copper is also oxidized, which is reduced back by reduction with hydrocarbons available from cracking of LPG. The fire-refined copper containing about 99.7% Cu is cast on rotating anode casting twin wheel as anodes each weighing about 390kg. The anodes are dispatched to tank house for electro-refining.

1.2.2 Brief Process Description - Electrolytic Refinery

The anodes cast in the smelter section are electro refined in electrolytic cell to produce cathodes based on the process technology developed at CRL, Townsville, Australia by Xstrata Technology, Australia. The process commonly known as ISA process uses permanent stainless steel electrodes as cathodes and copper anodes from Smelter as anodes in the electrolytic cells. Electrolysis of copper anodes is carried out by passing Direct Current from the rectifier. Copper ion from anode dissolves in electrolyte and gets deposited on the stainless steel cathode as sheets. The copper deposits are mechanically stripped from both sides of the stainless steel mother blanks. After stripping the S.S. mother blanks are recycled back to the electrolytic cell for subsequent use. The stripped copper deposits form the 99.99% pure Copper production from Cell house. One anode cycle lasts nearly three weeks and three cathode crops are drawn at weekly intervals.

The anodes after receipt from smelter are unloaded on to the feed conveyor of the anode preparation machine. The machine accepts good anodes and rejects bad anodes on weight basis. The anodes are pressed to straighten and lugs are milled in the machine for ensuring better electrical contacts. Prepared anodes are discharged on to separate spacing conveyors with desired spacing for loading into the electrolytic cells by tank house overhead cranes.

The anodes (57 Nos.) and stainless steel cathodes (56 Nos.) are placed in each electrolytic cell with a pitch of 100 mm, arranged in 40 sections of 30 cells each filled with electrolyte, with a composition of 38-55 gm/liter Cu and 150 - 190 gm/liter H2SO4. The electrolysis of copper anode is carried out by applying a

current density applied is 313 Amp/m2 of cathode surface. The electrolyte in the cells is circulated continuously at 65ºC to facilitate the nodular free uniform deposit of copper on cathode. The electrolyte is pumped from a circulation- collecting tank to an overhead tank through a heat exchanger. From the head tank, the electrolyte flows down under gravity to feed each cell at the rate of 35 liter/minute. The electrolyte enters the cell at bottom and leaves from the top ensuring the flow of the electrolyte throughout the cell. The return from the cells flows to circulation tank, through a mist eliminator. Additive reagents like Gelatine or Glue, Thiourea, HCl, etc are added to circulating electrolyte to improve the quality of the cathode deposit. To arrest the floating slime in the electrolyte a polishing filter continuously filters around 30% of the electrolyte in circulation.

The cathodes are harvested on a seven day cycle, constituting three cathode crops out of each anode cycle of 21 days. At the end of each harvest of 7 days, the cathodes are pulled out of the electrolyte cells. During this pulling time the entire block of cells is by passed from the main electrical circuit by means of electrical shunt and switch system. The 56 nos. of cathodes are lifted from the each cell by lifting bail attached to an overhead crane and transported to the cathode-stripping machine. In stripping machine, the cathodes are washed by high-pressure jet water in washing chamber. After washing the cathodes are flexed to release the copper deposits from the SS cathodes (Mother blanks). The deposited copper mass is stripped off from the blanks as copper cathode sheets and stacked one over other. The copper cathode sheets are stacked to a predetermined bundle size; it is further conveyed to next station for weighing.

The stripped mother blanks are advanced to the discharge conveyor and spaced at the desired pitch. The set of mother blanks, each consisting of 56 blanks, are lifted by lifting bail of overhead crane to place into electrolyte cells for start of new cathode cycle.

At the end of anode cycle, the anode scrap weighing around 50 kg each is removed from the cells by over head crane and placed in the feed conveyor of Anode Scrap Washing Machine, for washing of anode slimes from the anode scrap. The washed scrap anodes are recycled back to smelter.

The insoluble part of anodes, which consists of copper and precious metals settle down at the bottom of cells as anode slime during electro refining. After each anode cycle of 20 days, the electrolyte cells are washed with water and the anode slimes are collected in the slime storage tank.

In slime treatment plant, anode slime containing approximately 35% Cu, is treated with sulphuric acid at elevated temperature to reduce copper content. After leaching operation, the copper free slimes are filtered and treated further for separation of nickel, selenium and tellurium. Finally, precious metals, like silver and gold are recovered from the slime as dore metal. From the filtrate, tellurium is precipitated by cementation and tellurium free solution returned to electrolyte purification circuit.

During refining process, copper dissolves in electrolyte and impurities like nickel, arsenic, antimony, bismuth, and selenium etc., also go into the solution. For the production of the good quality cathode the impurities level in electrolyte should be as low as possible and the copper content in the electrolyte required to be maintained at the desired value. This is achieved by withdrawing a small portion of electrolyte from the electrolyte circulation system as a continuous bleed. The electrolyte bleed stream is treated in purification plant where in liberator cells electro winning of copper from electrolyte reduce the copper content. A portion of the treated electrolyte is recycled back to main circulation system and some portion is sent to WWTP for final treatment. During electro winning in liberator cells, arsenic, antimony, bismuth are precipitated and collected as a copper arsenic sludge for disposal.

1.2.3 Brief Process Description - Sulphuric Acid Plant

The sulphur dioxide gases generated during the copper concentrate smelting in ISA and matte converting operation in PS converter of copper smelter plant are treated in sulphuric acid plant for the production of sulphuric acid as a byproduct. The process of production of sulphuric acid consists of three principal steps:

 Cleaning of the sulphur dioxide gas from the ISASMELT furnace and PS converters;

 Catalytic conversion of the sulphur dioxide (SO2) gas to sulphur trioxide (SO3) gas according to the chemical reaction:

SO2 + ½ O2 (SO3)

 Absorption of the sulphur trioxide (SO ) gas by reacting with diluted H2SO4 to 3 form concentrated sulphuric acid (H2SO4).

The conversion of SO2 to SO3 is an exothermic, reversible and adiabatic reaction

and with increase in temperature the equilibrium constants become more unfavorable with respect to SO3 formations. The other factors, which favour

equilibrium conversions, are increase in oxygen concentration in the gases and or high pressures but the relative gains are rather small. In contrast to the unfavorable effect of high temperature on equilibrium it is found that the rate of reaction increases rapidly with rising temperature. Consequently, optimum performance requires a balance between the opposing effects of reaction rate and equilibrium. Thus, the gases entering the V2O5 catalyst normally are maintained

between 400 - 450ºC. Therefore, in order to achieve over-all high conversion efficiencies between 99.6% - 99.7%, it is imperative that the converter gases need to be cooled between stages to the above temperature range and also removing the partially converted sulphur trioxide formed normally after 2nd/3rd beds, before returning them to subsequent stages. This process is commonly known as Double Conversion and Double Absorption (DCDA).

1.2.3.1 Purification of SO2 Gas

The SO2 gas from the smelter and PS converters contains metallic dust, fume,

acid mist, water vapour and various other impurities like halides etc., which are not only detrimental to the catalyst used for conversion in the sulphuric acid production but also contaminate the product. The gases are therefore cooled,

cleaned in the gas cleaning plant comprising of gas cooling tower, Dynawave Scrubbing System and wet electrostatic precipitators. A portion of the weak acid from circulation system of the scrubbers is continuously bled, which is predominately consists of the halides like, fluoride, chlorides etc., to the Wastewater treatment plant. The wet gas precipitator electrically removes the acid mists formed during the downstream operations and optically fully saturated SO2 bearing gases are conveyed to the sulphuric acid plant.

1.2.3.2 Drying, Conversion and Absorption of SO2 to SO3

The optically cleaned SO2 rich gases along with dilution air to the extent required

for maintaining the requisite O2 /SO2 ratio are dried in a drying tower with 96%

concentrated sulphuric acid in counter current circulation. The dried gases after heating to 400-450 ºC passed through converter with cesium promoted vanadium pentoxide catalyst. The converted SO3 gases are absorbed in two absorption

towers where 98% concentrated sulphuric acid is circulated to produce 98.5% strength Sulphuric acid product.

CESIUM CATALYST AND XLP RING DESIGN

MECS provides guarantee on SO2 conversion through its highly active, low pressure drop catalyst. MECS XLP catalyst reduces pressure drop compared to ring type catalyst used in the same converter. Because of this, in a new plant the pre ssure drop can be reduced significantly. This ring type design is also used for Cesium catalyst, which was first patented by MECS in the 1960s. Cesium lowers the temperature at which initial conversion takes place, allowing MECS to guarantee ultra-high levels of SO2 conversion (>99.9%) without the use of a tailgas scrubber.

1.2.4 Brief Process Description – Phosphoric Acid Plant

The production of phosphoric acid is based on well known Hemihydrate Dihydrate process. The main raw materials for the phosphoric acid production are rock phosphate and sulphuric acid. The rock phosphate is reacted with sulphuric acid in a series of reactors to produce phosphoric acid. The solid waste (phosphogypsum) generated in the process is separated and transferred to the low / high density polyethylene lined gypsum pond through pipe conveyers. The off gas from the reaction containing hydrogen fluoride is scrubbed and converted to hydro fluro silicic acid, which is sold as a byproduct.

1.3 Plant Facilities

The major technological units envisaged for the copper smelter plant are as given below:

 Raw Material Handling System;  Isasmelt Smelting;  Converting;  Ferro sand Cleaning and Disposal;  Anode Refining and Casting;  Electrolytic Refining;  Continuous Copper Rod;  Sulphuric Acid Plant;  Phosphoric Acid Plant; and  Oxygen Plant.

1.3.1 Raw Material Handling System

Copper concentrate and rock phosphate will be imported from various sources at Thoothukudi port through shipment. These materials will be transferred into warehouse by tippers / wagons. The Copper Concentrate and the rock phosphate will be stored in separate warehouses. Similarly, other raw materials (fluxes) required for smelting viz. silica, limestone and quartz, will be procured from indigenous sources and stored in the raw material storage area, outside the warehouse.

1.3.2 ISA Smelting

The process for the smelting of copper from the copper concentrate by ISASMELT process, which is a proprietary technology of M/s Xstrata Technologies, Australia. The process flow diagram of ISA smelter and Rotary furnace is shown in Figure- 1.1.

FIGURE-1.1 PICTORIAL DIAGRAM OF ISA SMELTER AND ROTARY FURNACE

The ISA smelting comprises of the following main facilities:

 Furnace Building;  Furnace Raw Material Feed System;  The Smelting Furnace;  The Lance Handling And Services System;  Molten Matte/ Ferro sand Handling System;  Off Gas Handling System;  Waste Heat Recovery Boiler System;  Super Heater System in Sulphuric acid plant WHRB;  Turbine Generator System;  Air Cooled Condensers;  Cooling Water System; and  Hygiene Ventilation System.

1.3.2.1 Molten Matte/ Ferro sand Handling System

The furnace matte/ ferro sand is periodically tapped from the tap hole, which is provided with water cooled copper block. The tap hole is opened by a tap-gunning machine. The ferro sand/ matte together flow by gravity to the Rotary Holding Furnace (RHF) for ferro sand and matte settling and separation. The operation is being carried out in a horizontal cylindrical furnace MS shell lined with refractory. It is fired by Oxy-fuel burner to maintain the operating temperature of around 1200ºC. The off-gases are passed through a venturi before being led to the common hygiene ventilation system for scrubbing.

Ferro sand settled in the Rotary Holding Furnace (RHF) is being granulated separately in a dedicated launder system and is collected in the collection pond. Ferro sand granulation water overflows into a water pond, cooled in a spray pond and recycled to the nozzles of the granulation launders.

1.3.2.2 Off-Gas Handling System and WHRB System

The ISASMELT furnace is maintained under negative pressure at all times to ensure proper capturing of hot process SO2 bearing off –gases and these gases

are utilized for the recovery of the sulphur content as saleable byproduct of sulphuric acid.

The hot SO2 gases from the ISASMELT furnace, before being led to the sulphuric

acid plant passes through a waste heat recovery boiler (WHRB) to recover the heat to produce approximately 75 t/h of fully saturated steam at 77 bar a. The WHRB has a radiant section and a set of convection bank pendant tubes. The steam produced in the WHRB of ISASMELT is utilized to produce 7 MW of power in a condensing steam turbine set. The excess steam produced is utilized for process requirements.

A major content of the dust carried over in the off-gases is recovered underneath the WHRB through an air cooled drag chain conveyor and fed to a crusher together with the ESP dust for grinding to a size fraction suitable for pneumatic conveying to the recycle bin located in the day bin Building.

Off gases from the waste heat boiler gets cooled to a temperature of 350ºC and are further conveyed to a hot ESP having dust collection efficiency to achieve a dust content of approximately 100mg/Nm3. To maintain the manometric balance for the downstream equipment described above and maintain a negative suction pressure at the ISASMELT furnace inlet; an intermediate fan (ID fan) having a capacity of 120,000 Nm3/hr is provided after the hot ESP. The ID fan further delivers the off-gas to the gas cleaning section of the sulphuric acid plant for cooling and removal of the harmful impurities like fluorine, chlorine, arsenic etc before being sent to sulphuric acid plant for manufacture of sulphuric acid.

1.3.2.3 Hygiene Ventilation System

A provision has also been kept to collect secondary gases arising from ISA and RHF operations and is being treated in Hygiene Ventilation System having capacity of 362000 NM3/hr.

The Secondary emissions from ISA and RHF (such as the feed port, tapping port) are captured through hood arrangements and are scrubbed in the ISA/RHF Hygiene Ventilation Systems (HVS). The HVS consists of venturi scrubbers and demister arrangements. Milk of Lime is used as a reagent for scrubbing the secondary gases. The scrubbed gases, free of SO2 except for some traces are vented through a stack.

1.3.3 Converting using PS Converter

1.3.3.1 Raw Material Feeding System

Crushed revert and quartz (SiO2- 90% to the size of 20 - 25 mm) are fed to the converters during the operation. Two sets of bins consisting of two bins each (one for quartz and one for revert) exists for converters. These bins are filled by a common conveyor system.

Materials from these bins are reclaimed by vibro-feeders located below the bunkers and the reclaimed material is fed to the Converters.

PS Converter charging system is provided with dust extraction system (ESP) to prevent escape of dust to the atmosphere.

1.3.3.2 P.S. Converter

Molten matte tapped from the rotary holding furnace (RHF) in 10 m3 ladles is transferred to Pierce-Smith converter with the help of an E.O.T. crane. 4 Nos. of Cranes having capacity of (80 tonnes). Four converters (3 hot + 1stand by) exist with two converters in operation at a time.

During converting operation, air under pressure is passed through the specially designed tuyeres into the molten bath. The air oxidizes the matte to form ferro sand and blister copper. Crushed quartz (20-25 mm size) is added as flux in the converter. Quartz is being stored in a hopper located centrally between two converters. Weighed quantity of quartz is delivered to converter through weigh feeders. The converting process is a batch operation taking about 5.0 hours for producing 125 tonnes of blister copper in each cycle. The blister copper is transferred for further processing in the anode furnaces through dedicated blister

copper ladles having a capacity of 7-m3 each.

Ferro sand with 7 to 10% copper is tapped intermittently into ladles having a capacity of 10-m3 and recycled to rotary Ferro Sand cleaning furnace for recovery of contained copper content into matte and fixation of iron as ferro sand.

Converter off-gases at 1200oC are collected in double hood system. The converter hoods are in two sections; water cooled primary hood through which process SO2

off gases are collected having a capacity of 2,40,000 Nm3/hr gas handling capacity and secondary hood through which secondary gases are collected.

The gases then passes through an electrostatic precipitator (ESP) with a capacity of handling 240,000 Nm3/hr gas flow, to minimize dust carry-over to the sulphuric acid plant. Dust collected from off gases in ESP is recycled to ISASMELT furnace through a pneumatic conveying to the recycle bin located in the day bin Building. Converter SO2 off-gases are finally sucked by I.D fans and delivered to

Mixing chamber where they mix with ISASMELT furnace gases and utilized for sulphuric acid production.

The secondary off-gases from the secondary hoods are conveyed to secondary scrubber having capacity of 470,000 Nm3/hr.

1.3.4 Ferro sand Cleaning and Disposal System

1.3.4.1 Ferro sand cleaning Furnace Charging System

The coke and quartz are the main raw material required during process operation. A small quantity of the pig iron is charged using the shop EOT crane into a charging bin.

1.3.4.2 Ferro sand cleaning Furnace

Ferro sand from PS converter furnaces are transferred to the rotary ferro sand cleaning furnace by ladles with the help of EOT crane. The ferro sand is allowed to settle in the furnace (settling time around 1.25 hrs) where copper in ferro sand settles down and forms a layer of matte. Ferro sand from Ferro sand cleaning furnace is water granulated in a dedicated ferro sand granulation system having a capacity of 400 tpd. Matte (65% Copper) from Ferro sand cleaning furnace are tapped and charged back to the PS converters.

The Ferro sand cleaning furnace consists of steel construction with refractory lining mounted on roller cradles. Oxy-fuel burners are envisaged for heating and maintaining the ferro sand & matte under molten condition. The off-gases generated during Ferro sand cleaning furnace operations are cooled to 350ºC before being led to the common hygiene ventilation system for scrubbing before discharge to the atmosphere.

1.4.4.3 Ferro sand Disposal System

Ferro sand generated in the Ferro sand cleaning furnace is granulated separately in a dedicated launder system and is collected in the collection pond. Ferro sand granulation water overflows into a water pond, cooled in a spray pond and recycled to the nozzles of the granulation launders.

The granulated ferro sand settling pond is provided with a grab crane of 30 tonnes capacity which collects the ferro sand from the pond and discharges the same in a steel bunker. The ferro sand from the steel bunkers is unloaded into the outsourced tippler truck dumper and transported to the designated ferro sand yard within the plant boundary for storage and further sale/ disposal.

1.3.5 Anode Refining and Casting

Three number of anode furnaces are used for refining of blister copper to anode copper. Anode furnaces are provided with LPG & Oil burners. Blister copper is received in anode furnaces through ladles (7m3) with the help of EOT crane. Blister copper is first slowly oxidized to remove dissolved sulphur below 50 PPM by blowing air in it through tuyeres. The metal is subsequently reduced by use of LPG to control Oxygen around 1,500 PPM.

Fire-refined copper is cast into anodes (approx. 390 kg each) on rotating twin / single wheel casting machine having a capacity of 110 t/h by means of automatic anode weighing and casting device. Anodes from cast wheel is lifted by means of an automatic take-off device, cooled and stacked on a conveyor for onward conveying to the anodes preparation yard.

Hot off-gases from the anode furnaces are drawn by exhaust fan, scrubbed through hygiene ventilation scrubbing (HVS) before discharge to the atmosphere.

1.3.6 Electrolytic Refinery

Electrolytic refinery has two independent units namely;

 Tank house; and  Purification plant.

The process flow diagram of electrolytic refinery is shown in Figure-1.2(A). The technological facilities in Tank House comprise the following:

 Anode preparation facility;  Production cells;  Electrolytic circulation system;  Filtration of electrolyte;  Additive dosing facility;  Electrolyte storage;  Fume extraction;  Cathode stripping facility;  Anode scrap washing facility;  Extraction of slime;  Thickener; and  Thickener-overflow

The technological facilities in the purification plant comprises of following:

 Control cells;  Liberator cells;  Slime treatment facility; and  Fume extraction.

Besides, other major facilities like overhead cranes, rectifiers, bus-bar system, instrumentation and general services exists to meet the requirement of tank house and purification plant.

The copper anodes containing about 99.5% to 99.7% copper is electrolytically refined to about 99.99% purity which is necessary to obtain the required electrical conductivity for electrical applications.

The impure anodes contains around 99.5% to 99.7% copper, 0.15% oxygen and traces of other impurities such as precious metals. Anodes and stainless steel cathode plates are suspended alternatively (56 anodes and 55 cathodes) in the electrolysis cell. The electrolytic cells are connected in series to form one bank. A bank can be electrically isolated from others for the purpose of changing anodes and stripping by using short circuit switches. The current passes from cell to cell via intermediate busbars. Direct current required for electrolysis is provided by rectifier. From rectifier current flows through bus bars to banks and provides power for electrolysis.

The electrolytic cells are filled with electrolyte (copper sulphate, sulphuric acid, water and anode impurities). The electrolyte, which flows through cell, is preheated and circulated. The temperature of electrolyte is maintained at 630 C to 650 C and flow is maintained at 25-35 liters per minute per cell. During circulation of electrolyte, other reagents (Glue, Thiourea and hydrochloric acid) are added to achieve smooth fine-grained deposit. Electrolysis is conducted for about five to seven days (this time can be varied according to the current density).

FIGURE-1.2 (A) FLOW DIAGRAM OF ELECTROLYTIC REFINERY PROCESS

Copper is electrochemically dissolved from the anodes and gets deposited on the cathode, at a rate depending upon the strength of the current. The copper deposited cathode plates are removed from the electrolytic cells and are passed through cathode stripping machine, where cathodes are washed and copper is stripped from cathodes plates. The copper is bundled, weighed and strapped ready for use in Continuous Copper Rod Plant (CCR) or dispatched to customers. The mother banks return to the process for further deposition.

The undissolved part of anode, called anode scrap is washed free of electrolyte in Anode Scrap Washing Machine (ASWM) and is recycled back to smelter for remelting as anodes. The insoluble impurities (anode slimes) which settle at the bottom of the cell are collected and subjected to leaching process, where copper is removed from the slime. The leached slime is then filtered, dried and processed further.

During Electro-refining, some anode impurities (noble metals and heavy metals) gets dissolved in electrolyte. The build-up of concentration of these impurities in electrolyte solution affects the electrolysis process and results in poor quality of cathode. The concentration of such impurities in the electrolyte is controlled by bleeding off some quantity of electrolyte and making-up with fresh electrolyte solution.

1.3.7 CCR Plant

The CCR plant (Continuous Rod Plant) converts Copper Cathodes into rods by melting and rolling. Copper cathodes contain around 99.99 plus % coppers and is one of the purest forms of commercially available copper. Their copper cathodes are to be processed and made into rods of varying sizes to make them amenable for wire drawing. A brief description of the process is as under:

1.3.7.1 Technology

Our technology supplier for copper rod plant is "Continuous Properzi" Italy.

1.3.7.2 Main Raw Material feed

The raw material for the process is Copper Cathode of LME (London Metal Exchange) Grade A Quality. These cathodes along with pure in-process scrap from rod plant are used for melting. Cathodes are made into bundles and charged into a Shaft furnace with the help of a Skip hoist.

1.3.7.3 Shaft/Melting Furnace

The shaft furnace has LPG / Propane fired nozzle mix burners at the bottom to melt cathode at a temperature of 11000c and this melting temperature is controlled by a computer controlled system. The flame from the burner hits the cathodes and melts the same. Since there are column of Cathodes above the burners, the hot gases pass through the cathodes and transfers sensible heat to the descending charge thus increasing thermal efficiency. The fuel used is free from sulphur as Propane or LPG is used. Consequently there is no pollution of any nature because of Shaft furnace.

One specialty of the furnace is that there is no molten metal in the furnace and the metal as it melts freely flows out and the temperature is kept very low to prevent hydrogen pick up. The molten metal flows through covered Launders at a temperature of 11000c to a Holding furnace. 1.3.7.4 Holding Furnace and launder system

The holding furnace acts as buffer between melting and "continuous properzi" copper wire rod-making machine. The holding furnace is heated at a temperature of 11000c using Propane / LPG. The same fuel heats the launders. The temperature is kept as low as possible to prevent over oxidation and pick up of Hydrogen. 1.3.7.5 Copper Wire Rod Making Machine - "Continuous Properzi"

Copper Bar Preparation Unit

The molten metal from the Holding furnace is transferred to the Tundish through the premix burner fired Launders, whose level is automatically controlled. The Tundish then feeds the metal into a rotating wheel (trapezoidal groove) from one side. Here the metal gets solidified as the wheel cooled with water jet sprays. Solidified hot cast bar comes out of the wheel and passes through automatic shearing machine, cast bar straightener & shaving machine. Here the upper edges are shaved to remove the surface copper oxide scales. Rolling Mill

The copper bar then enters the Rolling mill at about 8500 c. Here it passes through Roughing mill, Intermediate mill and Finishing mill. The cross section is reduced in 11 stages with intermediate sections of triangles & circles to reach the required diameter of rods.

Pickling and Quenching

The rod exiting from the rolling mill is passed through Pickling unit (2% IPA solution in water and emulsion mixture) in order to reduce the Surface oxide of the rod. After the pickling the rod is quenched in water to reduce the temperature from 5000 C to 600 C.

Drying and Waxing

The quenched rod is then dried with compressed air in the Drier unit to remove the water droplets from the rod surface. In the waxing unit, a water-soluble wax is sprayed on the rod to protect the rod surface from tarnishing.

Coiling and Packing

Wax-coated rod passes through loop forming pipe to form orbital coils of 1.6-m diameter. These coils are produced in 2.2 & 3m weights as per the customer requirement. The rods are then compacted, strapped and stretch wrapped with HDPE Woven cut sheet for dispatch.

1.3.7.6 Wastewater

The only Wastewater generated in the process is the emulsion containing 5 % soluble oil. Discarding of emulsion is after 6 months depending upon roll life of the mill. The soluble oil is sold as secondary oil.

The gases from the Shaft Furnace do not contain any sulphur since the fuel (LPG) used is free of sulphur. The NOx content is negligible since combustion is at a very low temperature. There is no SPM as no soot formation takes place and the metal being melted is only a pure sold copper cathode.

The process flow diagram of CCR plant is shown in Figure-1.2(B).

FIGURE-1.2 (B) FLOW DIAGRAM OF CONTINUOUS COPPER ROD PLANT PROCESS

1.3.8 Sulphuric Acid Plant

The sulphuric acid plant has following facilities.

 Purification of off-gases in Gas Cleaning Plant;  Conversion of SO2 to SO3 in contact section by DCDA process;  Production of sulphuric acid in absorption section;  Waste heat recovery section;  Acid circulation system;  Product storage & tanker loading facilities; and  Tail gas scrubbing facilities.

The process flow diagram of gas cleaning plant and sulphuric acid plant are shown in Figure-1.3 and Figure-1.4 respectively.

1.3.8.1 Purification of off- gases in Gas Cleaning Plant

The partially cooled and clean gas from the primary gas handling system containing 11% to 12% SO2 is processed in SAP to produce sulphuric acid. The gas from the primary gas handling system is cleaned and condensed in a primary quencher vessel and a retention vessel. These units provide quenching of the hot gas to the saturation temperature and provide retention time for particle condensation and coalescence. In addition to the removal of coarser dust particles, these units, also absorb hydrogen chloride and hydrogen fluoride vapors present in the gas, if any.

The saturated partially cleaned gas, then enter the Venturi Scrubbers where sub- micron particles are captured and removed from the gas. The dust free gases are further cooled in cooling towers and cleaned in wet ESPs for removal of traces of fine particulates if any. The clean gas is next processed in SAP for production of sulphuric acid.

1.3.8.2 Conversion of SO2 to SO3 in Contact Section and Production of H2SO4 in Absorption Section

The gas from the Gas Cleaning section, saturated with water at 350o C, is drawn into the Drying Tower under suction from the main blower. Dilution air if required is added at this point to regulate the concentration of SO2 in the gas entering the Converter. The gas is dried by counter-current contact with a stream of 93% acid in the drying tower. Acid mist carryover in the gas stream from the drying tower is reduced by means of a mist eliminator located at the top of the tower. The dry gas from the drying tower is compressed in the main blower. The compressed gas is further heated to a temperature of 4100C in the heat exchangers before it contacts the catalyst (vanadium pentoxide) in the converter. The converter has 4 beds of catalyst. The catalyst beds not only facilitate the conversion of SO2 to SO3, but also controls the increase in gas temperature due to exothermic conversion of SO2 to SO3. The gas from the second converter bed where approximately 94% of the SO2 gets converted to SO3, is absorbed in 98.5% Sulphuric acid in the Intermediate Absorption Tower. Acid mist carryover is reduced by passing the gas through candle type mist eliminators. The gas from the intermediate absorption tower is again processed in 3rd and 4th converter bed where overall conversion of remaining SO2 to SO3 takes place. The gas from the 4th converter bed is again absorbed in 98.5% sulphuric acid in the Final Absorption Tower to produce sulphuric acid of desired strength. The produced acid is stored in storage tanks. Acid mist carryover is reduced through the use of Brownian Diffusion candle type mist eliminators. The gas leaving the Final Absorption Tower is discharged to atmosphere via Stack.

1.3.8.3 Waste Heat Recovery Section

In waste heat recovery system, the DM water is heated in economizer and low- pressure boiler by recovering heat from heat generated during conversion of SO2

to SO3 in converters to produce super-heated steam in SAP.

1.3.8.4 Product Storage

The 98.5% sulphuric acid produced is pumped from the product tank. The product acid from the storage tank is loaded in acid tankers for dispatch.

FIGURE-1.3 PICTORIAL DIAGRAM OF GAS CLEANING PLANT

Gas from GCP Waste Heat Recovery Boiler

2 Drying Tower Intermediate Absorption (DT) 3 Tower WHRB (IAT) 4 Final 1 Absorption Tower Blower (FAT) Converter Bed 98.5 % H2SO4 Product Acid

ATPT Air Cooler Acid Cool

Gas Stream DM Water Acid Stream

Stack

FIGURE-1.4 PROCESS FLOW DIAGRAM OF SULPHURIC ACID PLANT

1.3.9 Phosphoric Acid Plant

In order to balance the generation and the demand of sulphuric acid, a part of sulphuric acid is captively utilized for production of phosphoric acid.

The main raw materials for the phosphoric acid production are rock phosphate and sulphuric acid. The rock phosphate is reacted with sulphuric acid in a series of reactors to produce phosphoric acid. The concentration units are equipped with a fluorine recovery plant which produces 80 MTPD of hydrofluosilicic acid as 100% H2SiF6. The plant is equipped with an efficient scrubbing system to meet stringent environmental standards. The following steps are involved in the manufacturing process:

 Rock Handling;  Reaction;  Hemi-hydrate filtration;  Transformation;  Di-hydrate filtration;  Concentration; and  Acid storage.

1.3.9.1 Rock Handling

Rock phosphate is unloaded at Tuticorin port and brought to site by road or by rail and the rock is unloaded into the silo by means of unloading conveyors. Shovel loaders are used to feed the material to the reclaim hopper, from where the rock is conveyed to the main plant. Rock dust, which emanates from the system is collected, scrubbed with water and sent back to the first reactor.

1.3.9.2 Reaction

There are three agitated reactors in series operation. The reactors are of mild steel with 10 mm thick butyl rubber lining followed by carbon brick lining in three layers. The rock phosphate and recirculated acid slurry from the flash cooler are fed to reactor 1A. 40% of the calcium fed to Reactor 1A is precipitated in Reactors 1 A and 1B. Slurry from Reactor 1A overflows to Reactor 1B and finally enters Reactor 2. In Reactor 2, 98.5% H2SO4 and 36% P2O5 acid are added with the slurry and the remaining calcium in solution is precipitated. The system temperature is maintained at 98-1000 by means of a flash cooling system through which the slurry is pumped from the Reactor 2 to the Reactor 1B. The off gases evolved during reaction and during flash cooling are being scrubbed in reactor off gas unit and in Flash cooler off gas unit respectively. Scrubbing is done with water and hydrofluosilicic acid is produced at a concentration of 18% which is filtered in a silica filter to remove the silica content and the filtered acid is sent for storage.

1.3.9.3 Hemi Hydrate Filtration

This comprises of a horizontal belt filter and the slurry from the flash cooler is fed to the filter and washed counter currently. The acid collected from the first filtrate is product acid of 43% P2O5. Second filtrate is return acid of 36% P2O5 which is pumped back to the third reactor. Before the cake is discharged to the first transformation tank, final washing is done by 9% P2O5 acid from the dihydrate filter. A vacuum up to 0.25 bar is maintained by operating two centrifugal vacuum pumps.

1.3.9.4 Transformation

There are two transformation tanks, made up of mild steel, rubber lined and carbon brick lined, operating in series. An agitator is mounted for better mixing and keeping the slurry in suspension. Hemihydrate cake HH cloth wash liquor and Sulphuric acid are added to tank No. 1 and it overflows to tank No. 2. The residence time is sufficient to achieve conversion of Hemihydrate to dihydrate under controlled conditions and the slurry is then fed to the dihydrate filter.

1.3.9.5 Di-hydrate Filtration

This comprises of a horizontal belt filter and the slurry from the transformation tank is pumped to the filter and it is washed counter currently. The cake undergoes two washings before it is discharged to the gypsum slurry tank. The first filtrate of 9% P2O5 is used as final wash for the hemi-hydrate cake. The second filtrate is used for washing the hemi-hydrate filter cloth.

The gypsum generated is transported to gypsum pond through pipe conveyors to avoid spillage.

1.3.9.6 Concentration

The product acid of 43% P2O5 from the hemihydrate filter is further concentrated to obtain 54% P2O5 in the concentration section. Acid from the hemi-hydrate filter is pumped to the clarifier for removing the solids present before it is pumped to the concentrator. The clarifier is a mild steel rubber lined vessel and acid brick lined at the conical bottom portion. There are two clarifiers, one at the inlet of the concentrator. A centrally mounted rake mechanism is used for removing the sludge from the acid. The clear acid from the clarifier top is pumped to the concentrator and the sludge from the clarifier bottom is pumped back to the third reactor for recovering the entrapped P2O5. There are two concentrators operating in parallel with the fluorine recovery unit.. The concentrator is a mild steel rubber lined cylindrical vessel with a conical bottom. A graphite heat exchanger is used to raise the acid temperature to 850C by means of a low pressure steam (1.5 Kg/cm2). The steam is generated from “Smoke Tube” type Boilers. Acid circulation between the concentrator and the graphite heat exchanger is done by an axial flow pump of high volume and low head. The concentrated acid overflows from the concentrator (flash chamber) to a concentrated acid seal tank and is pumped to the concentrated acid clarifier through three acid coolers. The clarified acid is then pumped to the acid storage tanks. The non-condensable are removed by a vacuum jet system consisting of 2 steam jet ejectors operating on 10 Kg/cm2 steam and an inter condenser operating on cooling water. The ejectors maintain a vacuum of 53 mm Hg (abs.) The gases evolved during concentration are scrubbed in fluorine scrubbing system and the hydrofluosilicic acid (18%) is sent for storage.

1.3.10 Cryogenic Oxygen Plant

Oxygen is required for ISASMELT furnaces continuously and PS converters occasionally, for FSCF & RHF Oxy-Fuel burners intermittently.

These oxygen plants consist of main air compressors running simultaneously. The plant produces oxygen (95% purity) and nitrogen (99.9% purity). Argon production is not considered, since argon is not required. Liquid storage for LOX is provided.

1.4 Plant Layout

Copper Smelter Plant -II will be located in the SIPCOT Industrial Complex, Therkku Veerapandia Puram Village, Thoothukudi. The Total area earmarked is 128.805 Hectare of land allotted by State Industries Promotion Corporation of Tamil Nadu Limited, (SIPCOT), Government of Tamilnadu.

State Industries Promotion Corporation of Tamil Nadu Limited ('SIPCOT') handed over land of 131.3 ha for 1200 TPD copper smelter Plant – II. SIPCOT and executed three lease deeds, one, dated 16-02-2009 (for 36.16 hectares of land), the second, dated 07-10-2009 (for 93.33 hectares of land) and the third dated 03-06-2010 (for 1.84 hecatres) in favour of the Company at SIPCOT Industrial Complex, Thoothukudi and handed over the land as per lease agreements to the Company.

At present, we have 233.7 ha of land in total. Copper Smelter- I is located in 102.31 Ha. area, Copper Smelter –II will be located in 128.805 ha. and the Land kept in hand in Zone –A for future purpose is 2.585 ha.

Green Belt:

We have developed Green Belt around the Copper Smelter Plant-II boundary as per the TNPCB direction. We have till date developed 43 Ha of greenbelt in the total area earmarked for the existing and the proposed project site. After the Copper Smelter Plant–II project execution, our total green belt area will become 72.35 hectare as per the environmental clearance issued on 01.01.2009 in and around the existing Copper Smelter Plant-I, Copper Smelter Plant-II and Tamira-I (Employees Quarters) and railway siding area

FIGURE-1.5 OVERALL PLANT LAY OUT

Cu Concentrate

OXYGEN PLANT (1 No)

Oxygen Ferro Sand SMELTING FURNACE (1 No) Ferro Sand Matte + Ferro Sand Granulation Turbine WHRB

FERRO SAND CLEANING Energy RHF (2 Nos.) FURNACES (2 Nos.)

Matte

PIERCE SMITH Ferro SAP Sand H2SO4 CONVERTERS Sale (1 No.) (4 Nos.)

H2SO4 Rock Blister Copper Phosphate PAP (1 No)

ANODE FURNACES (3 nos) H3 Po4 H2Si F6

Gypsum Copper (Sale) Anode

PRECIOUS METAL PLANT REFINERY (1 No) (1 No.)

Copper

Cathodes CCR

FIGURE-1.6 PROCESS FLOW DIAGRAM OF COPPER SMELTER PLANT –II

1.5 Proposed Copper Smelter Plant –II -

Copper Smelter Plant –II is designed for the capacity of 1200 TPD of copper anodes production. The major design parameter of proposed copper smelter is presented in Table-1.1. The process flow diagram of the proposed copper smelter is shown in Figure-1.6.

TABLE-1.1 MAJOR DESIGN PARAMETERS OF PROPOSED EXPANISON

Sr. No. Parameters Details 1 Proposed Capacity 1200 TPD Copper Anodes 2 Concentrate requirement 5061 TPD 3 Silica requirement 789 TPD 4 Quartz requirement 173 TPD 5 Operating days in a year 348

1.5.1 Raw Material Handling

A new concentrate warehouse is proposed for storage of copper concentrate. Subsequently, increase in the unloading conveyors and tipper car will be done. Also, additional feed hopper arrangement will be provided.

1.5.2 Smelting Furnace

It is proposed to have new ISA furnace of 196 TPH for 1200 TPD of copper anode production. The design detail of the proposed ISA smelter furnace is given in Table-1.2.

TABLE-1.2 DESIGN DETAILS OF ISASMELT FURNACE

Sr. No. Parameters Design Capacity 1 Concentrate charged 196 t/hr (dry) 2 Flux Charged 32 t/hr Matte produced 91t/hr 3 4 Matte grade 63% Cu 5 Matte temperature 1180-1220oC 6 Slag Produced 112 t/hr 7 Cu in slag 0.5 % 8 Slag temperature 1180-1220oC 9 Tapping frequency of ISA 0.5 hr furnace 10 Gas Volume at furnace outlet 100,800 m3/hr 11 SO2 % in furnace off gas 35.6% 12 Gas temperature 1200oC 13 Process air required 6300 Nm3/hr

1.5.3 Rotary Holding Furnace and Ferro Sand Cleaning Furnace (RHF & FSCF)

Rotary Holding Furnaces (RHF) is provided for Ferrosand and Matte separation.

The furnace matte/ferro sand from ISA furnace will be periodically tapped from the tap hole which will be provided with water cooled copper block. The tap hole will be opened with a tap gunning machine. The ferro sand/ matte together will flow by gravity to the Rotary Holding Furnace for ferro sand and matte settling and separation. The temperature around 1260oC will be maintained. The off- gases from the furnace operation will be taken to the proposed ISA hygiene ventilation system for scrubbing.

Ferro sand settled in the Rotary Holding Furnace will be granulated separately in a dedicated launder system having a capacity of 150 tph and will be collected in the collection pond. Ferro sand granulation water will overflow into a water pond, cooled in a cooling tower and recycled to the nozzles of the granulation launders.

For ferro sand granulation system for Rotary Holing furnace, water circulation system of 1500 m3 /hr for the ferro sand granulation system will be provided.

The granulated ferro sand-settling pond will be provided with a grab crane of 30 tonne capacity, which will collect the ferro sand from the pond and discharges the same in a steel bunker. It is envisaged that the ferro sand from the steel bunkers will be unloaded into the outsourced tippler truck dumper and transported to the designed ferro sand dump area within the plant boundary storage and further sale/disposal. The design details of the Rotary Holding Furnace are given Table- 1.3. The ferro sand from the converters is cleaned in a ferro sand cleaning furnace for reducing copper in discard ferro sand. The ferro sand is allowed to settle in ferro sand cleaning furnace where again two layers of molten matte and ferro sand are formed. Matte from ferro sand cleaning furnace is treated in converters whereas ferro sand is tapped, granulated and discarded.

TABLE-1.3 DETAILS OF PROPOSED ROTARY HOLDING FURNACE

Sr. Parameters Design Capacity No. 1 Ferro sand density 3.0 2 Matte charged 2x550 MT 3 Matte grade 63% 4 Matte density 4.69 5 Matte tapping Intermittent depending on the level

DETAILS OF ROTARY FERRO SAND CLEANING FURNACE

Sr. No. Parameters Design Capacity 1 Ferro sand density 3.0 2 Matte charged 2 X 270 MT 3 Matte grade 64% 4 Matte density 4.69 5 Matte tapping Intermittent depending on the level

1.5.4 Converter

Four converters are proposed for the Copper Smelter Plant - II. The design specification of the pierce-smith converters (4 Nos.) is given in Table-1.4.

TABLE-1.4 DETAILS OF PIERCE –SMITH CONVERTER

Sr. No. Parameters Capacity 1 Matte treated per charge 210 tonnes 2 Matte grade 63% Cu 3 Blister copper (98.5% Cu) per charge 150 tonnes 4 Converter ferro sand (7-10% Cu) per 46 tonnes charge 5 Ferro sand temperature 1220 ºC 6 Average blow time 5.25 hrs. 7 Average process air flow 61,100 Nm3/hr 8 Quartz per charge 20 tonnes

1.5.5 Anode Furnace and Cast Wheel

Three anode furnaces are proposed for the Copper Smelter Plant – II and twin caster wheel will be provided. The design detail of anode furnaces (3 Nos.) is given in Table-1.5.

TABLE-1.5 DETAILS OF ANODE FURNACE

Sr. No. Details Capacity 1 Blister copper 310 tonnes 2 Casting machine Twin Caster 3 Casting capacity 110 tonnes/hr 4 Anode weight 390 kg 5 Copper in anodes 99.5%

1.5.6 Off Gas Handling

1.5.6.1 Primary Gas Handling System

The ISASMELT furnace will be maintained under negative pressure at all times to prevent uncontrolled escape of hot process SO2 bearing off -gases. These gases will be utilized for the recovery of the sulphur content as saleable by product of Sulphuric acid.

The hot SO2 gases from the ISASMELT furnace, before being led to the Sulphuric acid plant will pass through a waste heat recovery boiler (WHRB) to recover the heat to produce approximately 75 t/h of steam at 77 bar pressure. The WHRB will have a radiant section and a set of convection bank pendant tubes. The steam produced in the WHRB of ISASMELT will be utilized to produce 7 MW (average) of power in a condensing steam turbine set. The low-pressure steam produced will be utilized to drive the various feed pumps, and circulations pumps of the WHRB and other process applications.

A major content of the dust carried over in the off-gases will be recovered underneath the WHRB through an air cooled drag chain conveyor and fed to a crusher together with the ESP dust for grinding to a size fraction suitable for pneumatic conveying to the recycle bin located in the day bin building.

Off gases from the waste heat recovery boiler cooled to a temperature of 350ºC are further conveyed to a hot ESP to achieve a dust content of less than 100 mg/Nm3. To maintain the manometric balance for the downstream equipment described above and maintain a negative suction pressure at the ISASMELT furnace inlets an intermediate fan (ID fan) having a capacity of 120,000 Nm3/hr will be provided after the hot ESP. The ID fan will further deliver the off-gas to the gas cleaning section of the sulphuric acid plant for cooling and removal of the impurities before being sent to sulphuric acid plant for manufacture of Sulphuric acid.

1.5.6.2 Secondary Gas Handling System

Hygiene ventilation system has been envisaged for the following systems

ISA / Rotary Holding Furnace

i) A common double alkali scrubbing system shall be provided for the secondary gases generated in ISASMELT furnace, rotary holding furnace and Ferro sand cleaning furnace. This secondary scrubbing system can handle gas volume of 362,000 Nm3/h. Provision has also been kept for conveying the combustion off gases produced during the initial preheating of ISA furnace to the scrubbing system through a by-pass line.

Converter / Anode Furnace

ii) Secondary gases generated in PS converter and anode furnace shall be treated in a common double alkali scrubbing system. The secondary off-gas collected from secondary hood is conveyed by centrifugal fans having capacity of 470,000 Nm3/h to the scrubbing unit.

One common stack is envisaged for the entire ventilation & scrubbing system of ISASMELT, RHF, Ferro sand cleaning furnace, PS converters and anode furnace.

1.6 Proposed Copper refinery, Rod plant and Precious Metal recovery Plant

The refinery has been proposed to refine copper anodes to copper cathodes through electrolysis process and CCR has been proposed to treat copper cathode to produce copper rods by milling and rolling. In this project, a Precious metal and minor metal recovery plant is proposed.

1.6.1 Copper Refinery Process

The proposed Copper refinery capacity is 1525 TPD.

1.6.2 Copper Rod Process

The proposed rod plant capacity is 800 tpd.

1.7.1 Precious Metal Recovery Plant

Precious metal plant is a good value and pride plant for India. Hence new Precious Metal plant is proposed using state of the Art Technology. The Precious metal plant produces premium Gold, Silver, Platinum, Palladium will be recovered as Dore Metal for export, Selenium, Copper telluride, Bismuth Bi Sulphate, Nickel Sludge, and Nickel by refining slimes from the refinery and purification of Copper refinery electrolyte. The demand for precious metals as accessories and industrial materials is continuously growing due to its excellent chemical characteristics as well as superior workability in fabrication. Gold is widely used in the electronics industry, dental service, and as jewelry. Silver is used for soldering contacts, welding, plating and jewelry. Platinum and palladium are mainly used for catalysts in the automobile and petrochemical industries as well as jewelry and dental materials. Selenium is more wanted in Europe, China, US, and South American Region. It is mainly used in various industrial materials, such as a glass coloring agent, or in the sensitizer of a copying machine.

Precious Metal Recovery (PMR)

From Refinery From Refinery Slime Electrolyte Purification Refining Process  Selenium  Copper Telluride  Dore Metal  Bismuth bi

sulphate

1.7.3.1 PMR from Electrolyte Purification Process

1. Copper Telluride Recovery

Process Description

During copper leaching of anode slime, tellurium dissolves in the electrolyte. Tellurium is removed by cementation process using copper shavings by heating the electrolyte upto 95 – 105 °C in a tank (in the baskets designed for this purpose) and the electrolyte is re-circulated. Copper reacts with Tellurium to form Copper telluride which is filtered in a filter press and dried for sale.

Schematic diagram for Copper Telluride recovery is shown in Figure- 2.7(A).

Electrolyte from Refinery

Steam Filter Copper Telluride Press for Sale Tray Drier Cu

Solid

Liquid

Returns Copper Telluride Tank for Drying

Solution containing Tellurium Copper Telluride Polishing Filter free Electrolyte to Refinery

FIGURE-1.7(A) PROCESS FLOW DIAGRAM OF COPPER TELLURIDE RECOVERY PLANT

Input and output details for Copper Telluride recovery process are presented in Table-1.6. TABLE-1.6 INPUT AND OUTPUT DETAILS FOR COPPER TELLURIDE RECOVERY PROCESS

Input Electrolyte-CuSO4 30 L/MT of Cathode Copper Shavings 302 gm/MT of Cathode Water 2 L/MT of Cathode Steam 10 Kg/MT of Cathode Output Copper –Telluride (Cu-Te) 48 -75 gm/MT of Cathode Electrolyte-CuSO4 48 L/MT of Cathode Water Vapour 12 L/MT of Cathode

Environmental Impacts

Land Nil Air Water vapour Water 3.6 m3 / day Noise Nil

2. Bismuth Recovery Plant Based on MRT Technology

Technology Description

MRT has been used since 1990 in Hydro metallurgical operations for Impurity control and metals refining. The technology has been reviewed extensively and has proven to be very effective as an impurity removal strategy. MRT uses solid phases resins that contain selective metal recognition sites. The metal recognition is highly selective to the impurity metal versus the refined metal, allowing removal from the pregnant solutions.

Process description

The whole process flow is described in the following process cycle

1. (Loading) Electrolyte feeding from Cell house to the MRT Column. 2. (Pre- Wash). Feed solution is water or 2 M Sulphuric Acid. 3. (Elution) Feed solution is 9 M sulphuric acid solution. 4. (Post wash) Feed solution is water or 2M sulphuric acid.

In the loading cycle the Bismuth is retained by the resin. While the elution cycle the Bismuth is dissolved in the 9 M sulphuric acid Solution and finally Bismuth Bisulphate is precipitated once the temperature of the eluent is brought down.

Schematic diagram of the Bismuth removal process is shown in Figure1.7(B)

Electrolyte from Refinery

Steam Filter Bismuth Press for Sale Tray Drier Bismuth - Ion Selective Solid Resin Column Liquid

Bismuth free Electrolyte to Refinery

FIGURE-1.7(B) PROCESS FLOW DIAGRAM OF BISMUTH RECOVERY PLANT

Input and output details for Bismuth Recovery process are presented in Table- 1.7.

TABLE-1.7 INPUT AND OUTPUT DETAILS FOR BISMUTH RECOVERY PROCESS

Input Sulphuric acid 252 MTPA Water 7500 m3/annum Electrolyte Solution from the Cell house - - (feed containing Bismuth) Output Bismuth Bisulphate 125- MTPA on dry basis 150 (about 40% Bismuth content) Wash water Negligi Taken to WWTP ble Electrolyte Solution going back to Cell - - house ( Bismuth free)

Environmental Impacts

Land Nil Air Nil Water 22 m3 / day Noise Nil

3. Nickel Sludge Plant

Process Description

Composition of Bleed Stream:

1.Cu : <1% 2.Sulphuric acid : 30 gpl 3.Arsenic : 3500 PPM 4.Nickel : 10-20 gpl 5.Calcium : 500 PPM 6.Iron : 2000 PPM 7.Magnesium : 150 PPM 8.Bismuth : 5-10PPM 9.Antimony : 15 PPM

Neutralization:

 The bleed volume is stored in the collection tank.

 From there it is transferred to Reaction tank where it is neutralized to 4.6-4.9 pH by adding 48% pure caustic lye with agitation of bleed stream.

 The agitation can be done by running the agitator and also recirculating the bleed stream in the tank.

 Caustic is added slowly by caustic addition pump from caustic tank.

 During caustic addition, ensure that temperature will not exceed 85’C.

 After 30-min of agitation and recirculation, ‘As’ will be analyzed to ensure the complete removal of arsenic.

Reaction Chemistry and Stochiometric requirement of NaOH and Na2S

Reaction Chemistry of Neutralization reaction is as follows,

Neutralization:

H2SO4 +NaOH = >H2O + Na2SO4

Filtration:

Once, the ‘As’ comes to BDL in bleed stream, the filtration is started to separate the sludges from the bleed Stream.

Evaporation:

1.Psychrometric evaporator 2.Evaporator –01 3.Evaporator-02

Psychometric evaporator(PE):

Final filtrate from filter press is sent to psychometric evaporator through the cartridge filter to make the filtrate sludge free. (Psychrometric operation- any operation between air and water(moisture))

Operation of PE:

Psychometric evaporator is just like cooling tower. Liquid is circulated from the tray to top and from there it is sprinkled by having sprinkler. At the same time, induced draft fan which is at top starts sucking the air from atmosphere through the gap which existing in between tray and fills of packed bed.

During the operation of PE, when air moves from bottom to top it carries away the liquid droplet along with it. (i.e. humdification of air).This results in the loss of water content and hence Concentration of filtrate stream will increase. Since it is working on the principle of psychometric operation it is called as psychometric evaporator.

Evaporator-01

Liquid from PE is stored in feed tank. From there it enters the shell and tube evaporator where it is evaporated by applying steam at shell side. The outlet temperature of E-01 is maintained at 70’ C as the feed stream is getting splashed inside the vapor liquid separator (VLS-01) where the vacuum of 400mmHg is maintained. So it results in flash evaporation. The feed is being circulated in- between the vapor liquid separator and evaporator –01,till it gets concentrated to the required specific gravity.

FIGURE-1.7(C) PROCESS FLOW DIAGRAM OF NICKEL SLUDGE PLANT

Evaporator-02

The Evaporator-02 is also the shell tube evaporator, with vapor and uncondensed steam from E-01 as heating medium. Similar to E-01, the liquid is under recirculation in between E-02 and Oslo crystalliser. Main Purpose of this evaporator is to saturate the Oslo volume by continuous evaporation.

Oslo Crystalliser:

Oslo crystalliser is the crystalliser cum evaporator where the liquid is evaporated by flash evaporation and it is crystallized by obtaining a cooling gradient. The top portion of the Oslo is being called as VLS-02. At VLS-02, Liquid is getting splashed from E-02 outlet and the liquid gets vaporized and resulting in rise of Concentration of Oslo volume. As soon as, it reaches saturation condition it starts forming crystals as and when cooling gradient is obtained.

Centrifuge:

The crystals formed at Oslo crystalliser need to be continuously drained out to separate the liquid and crystals. The centrifuge is the mechanical separation device where centrifugal force is applied to drain the liquid out from the solid through by having the basket and filter cloth arrangement to get crystals of nickel and sodium sulphate.

The flow diagram of Nickel sludge preparation is shown above in Figure-1.7(C).

4. Nickel Recovery Plant

Composition of feed solution: 1. Nickel : 20 gpl 2. Arsenic : 14 – 20 gpl 3. Antimony : <120 ppm 4. Bismuth : <400 PPM

Process description - Recovery of high purity nickel

The process aim is to deplete nickel using the EMEW® electrowinning cell. The EMEW® cell is ideally suited to the selective removal of nickel for this application, and the aim is to recover a nominal 1500 kg of nickel per day as a high purity nickel cathode. The plant would operate a single circuit to deplete nickel from 20 g/l to 2 g/l. This can be achieved using either continuous or batch processing.

Proposed Operational Conditions Nickel in feed g/l 20 Current density (max) a/m² 600 Current per cell (max) amps 300 Number of cells 90 Total cathode area M² 45 Electroly temp. (max) 60 °C

FIGURE-1.7(D) PROCESS FLOW DIAGRAM OF NICKEL PLANT

1.7.3.2 PMR from Refinery Slime Refining

The expected annual slime quantity to be treated in our precious metal recovery plant is 1734 MT.

Typical analysis of Anode slime is detailed below.

Sr. No Element Unit Typical Assay 1 Ag % 20.00 2 Au % 3.50 3 Pd % 0.02 4 Pt % 0.001 5 Se % 20.00 6 Cu % 2.00 7 Te % 1.80 8 Bi % 2.5 9 S % 9.50

10 O2 % 16.00 11 SO4= % 25.00

The slime is in black powder form, having a particle size of < 0.5 mm. The extraction of precious metal is in four stages.

1. De-selenisation, 2. Dore Smelting,

The Process description of each stage is shown in Figure-1.7(E).

FIGURE-1.7(E) PROCESS FLOW DIAGRAM OF PRECIOUS METAL EXTRACTION

1. Selenium Recovery Plant

Technology /Process Description

The technology is derived from M/s. Outotec, Finland. The slime from the copper leaching decopperised slime is dropped from the filter press plates onto the roasting trays. These are transported by forklift into the roasting furnace. The selenium is roasted from slime in the electrically heated furnace with a batch size of 2000 kg. The roasting temperature is 4500C. Oxygen and sulfur dioxide gases are fed as reagents into the furnace. The reaction result, selenium dioxide gas (SeO2), is sucked from the furnace through the ejector into process solution. In this solution selenium dioxide is reduced to elemental selenium by sulfur dioxide. The elemental selenium is collected into the Circulation Tanks. The selenium is filtered, washed and dried. The recovered selenium is commercial grade selenium, purity min. 99.5 %.

Main reactions in the furnace, (1, 2 and 3) and in the circulation system (4) can be described:

Se + O2 ->SeO2 (1) Ag2Se + O2 ->2 Ag + SeO2 (2) Ag2Se + 2 O2 + SO2 ->Ag2SO4 + SeO2 (3) SeO2 + 2 SO2 + 2 H2O ->Se + 2H2SO4 (4)

The selenium free slime on the roasting trays is discharged into the feeding bin of the Doré-smelting furnace.

The Process description of Selenium Recovery plant is shown in Figure-1.7(F).

O2 / Compressed Air

WWTP SO2

De-Copperised Selenium Slime Roasting Furnace WWTP HOLD-UP

Selenium Steam free Slime Liquid

Compressed Air Ejector Rotary LPG Vacuum Solid Drier TROF Converter Circulation Circulation Selenium Tank - 1 Tank - 2 Powder for Sale DORE DORE Circulation Anode Pump Filtration Pump Gold & Silver Refining Solution Containing Selenium

FIGURE -1.7(F) PROCESS FLOW DIAGRAM OF SELENIUM RECOVERY PLANT

Input De-copperised slime: 1734 MT Water: 9 m3/MT SO2: 0.8 MT/MT O2: 0.4 MT/MT Air: 125 m3/MT Steam: 0.7 MT/MT Output De- selenised slime: 1296 MT Selenium: 438 MT Gas: 150 KNm3/MT WWTP bleed: 7.0 m3/MT

Environmental Impacts:

1 Land: Nil 2 Air: Emission of gas 500 Nm3/ Hr containing SO2 : 100 mg/Nm3, Co2 : 0.1%,Nox:<1 gm/batch, H2O content : 25% max and solid : 300 mg/Nm3, Temperature : 80 C, Velocity : 3 m/s 3 Water Consumption of 9 m3 / MT of De-Copperised slime 4 Noise: Nil

2. Doré Smelting Process

The Process description of DORE smelting is shown in Figure-1.7(G).

I step: Dore Anode preparation from Slime

De-selenised slime is mixed with the fluxes like Soda, borax (anhydrous), cement and smelted in Doré furnace (TROF-converter) at 1300 deg c. After refining the metal, it is casted as anodes by tilting the converter. The slag is also separated out in this process. Primary slag is recycled in copper smelter and the secondary slag is re-smelted in Dore furnace back.

O2 / Compressed Air

SO2

De-Copperised Slime Selenium Roasting Furnace

Selenium free Slime

Compressed Air

LPG

TROF Converter

DORE Anode

FIGURE -1.7(G) PROCESS FLOW DIAGRAM OF DORE SMELTING PLANT

1.8 Proposed Project – Acid Plants

1.8.1 Sulphuric Acid Plant Process (SAP)

For the Copper Smelter plant -II, sulphuric acid plant having capacity of 5900 TPD will be provided to handle the gas volume of 3,90,000 Nm3/h. A Gas cleaning plant is proposed for this SAP.

1.8.2 Phosphoric Acid Plant (PAP)

For the Copper Smelter plant -II, Phosphoric acid plant having capacity of 800 TPD will be provided.

1.9 Proposed Project – Utilities and WWTP

1.9.1 Utilities

It is proposed to install RO plant of capacity for the treated wastewater. As part of this project, it is proposed to install one (1) new oxygen plant.

It is proposed to install one Desalination Plant of 10000 m3/day capacity in the coastal area to meet the additional raw water requirement.

1.9.2 Wastewater Treatment Plant (WWTP)

WWTP-1, 2 and WWTP 3 will be provided for waste water generated from the proposed project facilities.

1.10 Project Cost

The total cost for the proposed Copper Smelter Plant -II project is estimated as Rs.2500 Crores. The break-up of project cost is presented in Table-1.8. The environmental protection cost including the chimney in the total project cost is about Rs. 475 Crores.

TABLE-1.8 DETAILS OF PROJECT COST

Sr. Particulars Cost in Crores No. Rs. 1 Basic process equipments and machineries 1500 2 Civil structures 275 3 Utilities 140 4 Air Pollution Control Measures (SAP, ESP) 475 5 Wastewater Pollution Control Measures 20 (WWTP, STP) 6 Environmental Improvement Plans 90 (Double hood and Energy conservation) Total 2500

Annexure-2

Solid Waste Management and Waste Water Treatment

ANNEXURE-2 SOLID WASTE MANAGEMENT

Solid Waste Generation

The solid waste management for all the types of solid wastes, handled by the unit is explained below. The wastes include solid wastes such as Lime Grit & Hazardous wastes such as WWTP Cake, Scrubber Cake, ESP/Gas Cooler Dust, and Spent Catalyst from Sulphuric Acid plants, WWTP Slime, Spent Oil & Oil Sludge. The details of solid waste generation is described below.

Lime Grit

The lime grit will be generated from the milk of lime (MOL) preparation plant, which is a residue of lime after the MOL of required gram/litre is prepared. In this project, the lime grit generation will be about 15 TPD. Since, the lime grit contains lime content of 30 -35 %, the same will be recycled back into ISA furnace in place of flux material.

Hazardous Wastes Generation

ETP Cake

ETP cake is the solid waste generated from the GCP Wastewater treatment process. It is mainly made up of CaSO4. WWTP Cake is hazardous in nature as per Schedule -1 of Hazardous Waste Rules-2008. Hence, WWTP cake will be stored in Secured land Fills (SLF’s) designed as per CPCB guidelines. The composition of WWTP cake is given in Table-2. 3

Scrubber Cake

The scrubber cake is a solid waste generated during the scrubbing of the secondary / Tail gases before dispatching into the stack. The detailed composition of the same is given in Table-2.3. This is mainly made up of gypsum and lime. It will be stored in the Secured Landfill Facility (SLF) and beneficial applications as per TNPCB guidelines.

Spent Catalyst

V2O5 is used as a catalyst in the catalytic converter of the Sulphuric Acid Plant to convert SO2 to SO3. To maintain the conversion efficiency, the catalysts are replaced once in every 2 years, during the turn-around period. These spent catalysts are hazardous in nature and hence is being disposed in Secured Land Fill facility. The generations of spent catalyst is estimated about 10.0 TPA.

Secondary Production of copper (ETP Slime Sludge From refinery) Slime

The ETP slime is generated from the Refinery ETP. These are the impurities from the anode.

ESP / GC Dust

The ESP dust is generated from the ESP’s attached to ISA & Converter Primary Gas streams. WHRB dust is generated from the Waste Heat Recovery Boiler attached to ISA. Gas cooler dust is generated from Gas Coolers attached to the Converters. These dusts will be immediately recycled back into ISA furnace as a measure for waste minimisation by recycling through pneumatic dust conveying system placed in ISA ESP, WHRB and Converter ESP. This process recovers the copper in the dust back into the system. The composition of ESP and GC dust are presented in Table-2.4.

Spent Oil

The lubricating oils used in the maintenance processes generate used oil / spent oil. These are all categorized as Hazardous Waste and will be disposed to the MoEF&CC approved vendors within the operating state.

Oil Sludge

The Oil sludge is generated from Oil Storage facilities Viz. Furnace Oil Storage tanks. This will be collected from the Storage tank during cleaning operation in every annual shut down.

The details of non-hazardous and hazardous solid waste generation are presented in Table-2.1 and Table-2.2. The Composition of solid waste and Hazardous waste are given in Table-2.3 to Table -2.7.

Toxic metal containing residue from ion exchange from ion exhange material in water purification and RO plant Reject.

During resin change in water purification and RO plant rejection, waste will be generated and it contains some toxic metals, which will be stored along with WWTP cake in SLF.

Non Ferrous Scrap

Non ferrous scrap is generated from Copper Refinery and it will be recycled back to the authorized non scrap recyclers approved by CPCB.

Resin from Bismuth Plant

Bismuth is recovered in ion selective resin absorption process and this packed resin will be regenerated once in 5 Years.

Precious Metal Slag from TROF converter of DORE process

The precious metal slag is generated from TROF converter attached to DORE Process streams. These slag will be immediately recycled back into smelter as a measure for waste minimisation by recycling through mechanical and tractor conveying system. This process recovers the precious metals in the slag into the system.

Slag Composition: Au:0.004% Ag:0.26% Cu:2.9% Pb:14.16% Te:2.34% Se:0.8% As:3.47% Antimony:1.10% Bismuth:3.60% Sulphates :14%

TABLE-2.1 NON HAZARDOUS WASTE GENERATION

Descriptio Quantity (TPD) Method of Method of Disposal n Copper Smelter Collection Plant -II Lime Grit 15 Mechanical Recycled in ISA Smelter as (Loader & a Flux and will be sold to Tippler) pigment industries.

TABLE-2.2 HAZARDOUS WASTE GENERATION DETAILS

Description Quantity Method of Method of Collection Disposal ETP cake 80 TPD Mechanical Stored in Secured (Arsenic bearing (loader and tractor) Landfill Facility. sludge) Scrubber Cake 120 TPD Mechanical Stored in Secured (Sludge from WWTP (loader and tippler) Landfill facility / & Scrubber) Beneficial application as suggested by TNPCB. Spent Catalyst 6.0 MT Bagged in Polythene Stored in Secured (Spent Catalyst) Per year bags and Stuffed in Landfill facility Drums Secondary 9 TPD Mechanical Sold to CPCB Production of registered copper recyclers (ETP Slime Sludge From refinery) ESP / Gas Cooler/ 90 TPD Mechanical Recycled in WHRB Dust (loader and Tractor) Smelter (Process Residue ) immediately Spent Oil 384 KL Per Collected in Drums Sold to CPCB (Used / Spent Oil) Year registered recyclers Oil Sludge 16T Per Collected in Drums Sold to CPCB (Oil containing Year registered Cargo residue, recyclers Washing water and sludge) Toxic metal 40TPD Bagged in Polythene To be stored in Containing residue bags and Stuffed in SLF along with ETP from ion exchange Drums Cake material in water purification and RO plant reject Non Ferrous Scrap 6.5 TPD Mechanical Contains precious (loader and Tractor) Non ferrous metal Recycled to authorized CPCB recyclers Resin from Bismuth 3 T once in Mechanical Will be Stored in Plant FIVE years (loader & tippler) Secured Landfill facility Precious metal slag 18 TPD Mechanical Contains precious from TROF (loader and Tractor) metal Recycled in converter of DORE Smelter Process (PMR) immediately

TABLE-2.3 LIME GRIT, SCRUBBER & ETP CAKE COMPOSITION

Parameter Scrubber Cake Lime Grit ETP Cake Iron (%) 0.05 1.0 – 2.0 4.5 – 6.2 Arsenic (%) BDL BDL 0.8 – 1.5 Copper (ppm) 10 – 20 < 2 1300 – 2100 Bismuth (ppm) BDL BDL 65 – 185 Cadmium (ppm) BDL BDL < 15 Chromium (ppm) BDL BDL < 15 Cobalt (ppm) BDL BDL < 20 Nickel (ppm) BDL BDL < 15 Lead (ppm) BDL BDL 20 – 50 Antimony (ppm) BDL BDL < 20 Selenium (ppm) BDL BDL 20 – 40 Zinc (ppm) 1.0 – 2.0 10 - 20 1100 - 2500 CaO (%) 30 – 32 40 - 50 28 - 30 Sulphate (%) 40 – 45 1.0 – 2.0 38 – 42 Silica (%) < 0.5% 30 - 45 < 0.5% Moisture (%) 45 60 35 BDL - Below Detectable Limit

TABLE-2.4 COMPOSITION OF ESP /GAS COOLER DUST

Parameter ESP / Gas Cooler Dust Copper (%) 15 – 25 Iron (%) 10 – 15 Sulphur (%) 2.0 – 10.0 Silica (%) 1.0 – 2.0 Lime - CaO (%) 1.0 – 2.0 Arsenic (ppm) 30 – 50 Bismuth (ppm) 5 – 10 Cadmium (ppm) 8 – 10 Chromium (ppm) 1.0 – 2.0 Cobalt (ppm) 250 Nickel (ppm) 75 – 100 Lead (ppm) 200 – 400 Antimony (ppm) 5 – 10 Selenium (ppm) 2- 4 Zinc (ppm) 1000 – 2000

TABLE-2.5 SPENT CATALYST COMPOSITION

Parameter Spent Catalyst V2O5 (%) 6 - 7 % K2O 9 - 12 % Na2O 1 - 2 %

TABLE-2.6 SPENT OIL AND OIL SLUDGE COMPOSITION

Parameter Spent Oil Oil Sludge Specific Gravity >0.9 g/cc >1.25 g/cc % Solids < 2 % < 5 % Flash point >100'c >66'C Calorific Value (Cal / g) 7500-9000 10000 Reactivity Flammable Highly Flammable Explosivity NA NA

TABLE-2.7 COMPOSITION OF ETP SLIME

Parameter WWTP Slime Copper Sulphide (Cu2s) 15 % Iron Hydroxides ( Fe(OH)2 ) 7 - 8 % Nickel Hydroxides(Ni(OH)2 ) 20 % Gold 0.5 % Sodium / Calcium Sulphate 30 - 40 % Other Elements 3 % Moisture 10 - 15 %

All of these wastes will be managed in an environmentally sound manner. The handling, storage & management plan for the solid waste to be generated with the proposed project is well thought out.

Wastewater Generation and Treatment

The total wastewater generation from the Copper Smelter plant –II will be 4551 m3/day and the entire wastewater generated will be reused. Three WWTPs will be provided to treat the waste water.

The production facility of the smelter includes a Sulphuric Acid Plant (SAP) & Phosphoric Acid Plant (PAP) to meet the requirement of the Copper Smelter.

The liquid Wastewaters generated from SAP, Refinery section and Precious Metal Recovery Plant contain mainly inorganic contaminants viz., heavy metals, Sulphate etc, which needs to be reduced to within the acceptable levels for reuse in the plant.

The other Wastewaters generated from Phosphoric Acid Plant, Continuous Copper Rod Plant, Cooling Towers, Boiler blow down and WWTP raw water does not require any treatment for re-use/recycle. Similarly, the scrubbers bleed off, which is in slurry form and needs to be filtered for solids only.

Wastewater Generation

The Wastewaters generated from the total plant are divided into following two parts:

 Wastewaters Treated and recycled to system; and  Wastewaters Recycled in Process without treatment.

The Wastewaters recycled back to system with and without treatment are presented in Table-2.8 and Table-2.9 respectively. TABLE-2.8 WASTEWATERS TREATED AND RECYCLED TO PROCESS

Sr. No. Unit Copper Smelter Plant -II (m3/day) 1 Gas Cleaning Plant 1100 2 Scrubbers 1100 3 Refinery, PMR 101 5 Domestic Sewage 100 Total 2401

TABLE-2.9 WASTEWATERS RECYCLED TO PROCESS WITHOUT TREATMENT

Sr. No. Unit Copper Smelter Plant -II (m3/day) 1 Cooling Tower Blow Down 500 2 PAP-Filter Wash 1200 3 PAP- Plant Wash 50 4 Smelter SAP and PAP Boiler Blow Down 85 5 Continuous Copper Rod Section 75 6 WWTP raw water consumption 240 Total 2150

Wastewater Treatment

Different types of Wastewater Treatment Plants (WWTPs) are proposed in Table- 2.10 and the schematic diagrams of WWTP-1, WWTP-2 and WWTP-3 are presented in Figure-2.1 to Figure-2.3.

TABLE-2.10 DETAILS OF WASTEWATERS TREATMENT PLANTS

Sr. No. Source of Wastewater WWTP 1. Scrubbers WWTP- 1 2. Gas Cleaning Plant Wastewaters WWTP -2 3. Gas Cleaning Plant Wastewaters WWTP -3

The treated Wastewater is recycled back into the process areas Viz.-Ferro sand Granulation, Milk of Lime preparation, Gas Cleaning Plant and Scrubbers, through a Concrete Surge Pond.

The characteristics of wastewater before treatment and after treatment of different WWTPs are presented in Table-2.11. TABLE-2.11 CHARACTERISTICS OF WASTEWATER

Parameter Before Treatment After WWTP- 1, WWTP 2 and 3 Treatment Scrubber Gas Cleaning Slurry Plant pH 6.5 – 9.5 0.8-1.6 6.5 – 9.5 Total Suspended Solids 4 – 8 % 4500-6000 75 - 90 (ppm) Total Dissolved Solids 6000–8000 45,000-55,000 1800 - 2400 (ppm) Sulphate (ppm) 3 – 6 % 32000-45000 1300 - 1800 Chloride (ppm) 200 - 300 300-500 300 - 450 Fluoride (ppm) < 2 25-40 < 2 COD (ppm) 120 100 < 50 BOD (ppm) 5 NA < 10 Iron (ppm) < 10 250-400 < 2 Arsenic (ppm ) < 0.1 150-2750 < 0.15 Copper (ppm) < 10 150-750 0.5 – 2.0 Bismuth (ppm) BDL 1-15 < 0.1 Cadmium (ppm) < 0.1 10-40 0.2 – 0.5 Chromium (ppm) BDL 0.2-1.0 < 0.05 Cobalt (ppm) < 0.1 0.2-1.5 0.1 – 0.5 Nickel (ppm) BDL 3-10 0.2 – 0.5 Lead (ppm) BDL 2-30 0.05 Antimony (ppm) BDL 2-10 BDL Selenium (ppm) BDL 0.5-3 BDL Zinc (ppm) < 2.0 50-1000 0.2 – 0.5

 Process Description of WWTP-1

The Wastewaters from HVS / Secondary Scrubber Slurry will be treated in WWTP -1.

The Secondary gases from all furnaces (viz., ISA, RHF, FSCF Converters and Anode Furnaces) are captured by hood arrangements and taken to Hygiene Ventilation systems of ISA/RHF/FSCF, the Secondary Scrubber arrangement of Converters/AF, Tail gas scrubber - gypsum slurry. The SO2 gases are scrubbed in the Scrubbers using Lime in all scrubbers, except TGS, where NaOH will be used and the scrubbed liquor will be taken to WWTP -1 for treatment.

There will be no chemical treatment taking place in this WWTP. The bleed off - slurry from Converter / Anode Furnace Secondary scrubber system, ISA/RHF/FSCF Scrubber, and tail gas scrubber gypsum slurry will be only thickened by passing it through Reaction tanks, Flocculators and Thickeners. The thickened slurry will be then filtered in the Filter press and the cake from the filter press will be taken to the Secured Land Fills.

 Process Description of WWTP-2

Surge Tank

The Wastewater from the Gas Cleaning Plant of Sulphuric Acid Plant and Refinery Wastewater will be pumped to the Surge (holding) tank.

Reactor-1

The Wastewater from the holding tank will be pumped in Reactor-1, where lime slurry and ferric sulphate will be added to maintain a pH of 5.5. Ferric sulphate reacts with soluble reactants to produce stable ferric compounds and gypsum.

Clarifier-1

The overflow from Reactor-1 will go to Clarifier-1. Flocculent will be added in the launder to aid flocculation and agglomeration of the fines generated during the chemical reaction in Reactor-1.

Filter Feed Surge Tank and Filter Press.

The underflow from Clarifier-1 will come to this tank for filtration in two pressures filters. The cake from pressure filter will be taken to secured landfill facility. The filtrate will be taken to Reactor –1 for further treatment.

Reactor-2

The second stage reactor tank content will react with lime slurry and ferric sulphate to complete the reaction process at a pH of 7.5.

Clarifier-2

The second stage Clarifier has the same function as Clarifier-1. The under flow from this clarifier will be recycled back to Reactor-1 and the overflow (treated Wastewater) will be pumped to the final holding tank.

 Process Description of WWTP-3

The bleed envisaged from GCP and Refinery Bleed will be combined together and treated using sodium sulphide treatment process. Function of new sulfide addition system will be to precipitate the majority of heavy metals (as metal sulfides) present in the weak acid Wastewater in the form of hazardous waste. The remaining weak acid free from trace metals will be neutralized with lime to produce Gypsum, which will be essentially non-hazardous.

Primary Filtration

The input to WWTP-3 will be weak (H2SO4) acid, which will be taken in waste acid tank. From the waste acid tank, the untreated Wastewater will be taken to Flash mixer and Flocculator with the addition of Polyelectrolyte for settling suspended solids in the Wastewater. Then, the Wastewater will be taken to Primary Clarifier and then to Filtering system through Underflow tank of Primary Clarifier. From the filter, the Filtrate will be returned back to the Flash mixer & Flocculator and sludge will be taken to SLF.

Sulphidation Process

Sulfide precipitation takes place in four reactors in series. Sodium sulfide will be added to all the reactors to precipitate the insoluble metal sulfides in acid. The gases and vapours evolving from these (1, 2, 3 & 4) reactors are taken to the scrubbers. After reaction (in scrubbers), the slurry will be taken to Flocculator, where Sulphuric acid and Poly electrolyte will be added. Sulphuric acid will be added for removal of free H2S gases in the slurry. The thickened slurry from the Flocculator will be taken to Secondary Clarifier, where water spray will be arranged for capturing the acid mist evolving from the Clarifier. The underflows from Secondary Clarifier will be filtered. The sludge will be taken to SLF and the over flow will be taken to Pressure filter for filtering fine particles.

Neutralisation Process

The filtered treated water will be taken to Lime reactor for neutrilisation and the slurry from the reactor will be taken to Drum filter for filteration, through Clarifier. The Gypsum generated from this neutrlisation process will be sold along with Phospo-Gypsum. The filtrate from the Drum filter will be returned back to lime reactor and the overflow (Treated Water) from the clarifier will be processed for recycle.

Scrubbers

The vapours and H2S gases from the reactors will be taken to the bottom of the Scrubber-1 (Wastewater Scrubber), where the Wastewater from the primary filtration system will be sprayed from the Top of the scrubber. The Wastewater will be reacted with the H2S gases and the remaining H2S gases will be taken to Alkali Scrubber. The reacted Wastewater will be drained to Reactor-1 for further reactions. The Wastewater scrubbed gases will be entering the bottom of the Scrubber-2 (Alkali Scrubber) and the diluted Sodium hydroxide will be sprayed from the top of the scrubber. The resulting scrubbed liquor (Na2S) will be taken to the reactors for treatment. The scrubbed gases will be vented out through a vent.

FIGURE-2.1 SCHEMATIC DIAGRAM OF WASTEWATER TREATMENT PLANT-1

FIGURE-2.2 SCHEMATIC DIAGRAM OF WASTEWATER TREATMENT PLANT-2

FIGURE-2.3 WASTEWATER TREATMENT PLANT-3

Reverse Osmosis Plant

It is proposed to install RO plants to treat WWTP treated water These RO Plants are not only ensuring Zero discharge but also reduces the total raw water consumption of the expanded plant.

Planned Operation Philosophy of Wastewater Recycling system:

1. Pretreatment to reduce / to remove hardness (Equalization tank, Reaction tank, SCR); 2. Tertiary treatment (Chlorination, Multi grade filter); 3. Sludge dewatering system (Sludge pit, Centrifuge); 4. Advance Membrane Technology (Ultra filtration, Reverse Osmosis); and 5. RO Reject disposal system (Thermal evaporation system).

Equipment and Process:

Wastewater Collection Tank Complete mixing of the collected Wastewater shall be ensured by supplying air through air blower and HDPE air grid provided in Wastewater collection tank. Reaction Tank The Wastewater from Equalization Tank shall be pumped to Reaction tank, where Lime Soda treatment shall be provided for removal of hardness from Wastewater. Flash Mixer The Wastewater from Reaction tank shall be routed under gravity to Flash mixer where coagulant dosing shall be done to enhance setting of solid particles. Solid Contact Clarifier (SCR) After Chemical reaction with the coagulant, Wastewater will enter under gravity to Solid contact clarifier. Polyelectrolyte shall be dosed in the SCR. The Solid contact clarifier has better hydraulic performance and has minimum retention time for effective solids removal. Multi-Grade Filter Wastewater from MGF feed Tank shall be pumped to MGF for removing suspended solids, turbidity etc. The arrested solids/ turbidity in the filter shall be removed by back washing. Sludge Dewatering System-Centrifuge The sludge generated from Solid contact Clarifier shall be drained into the Sludge holding pit. The collected sludge shall be pumped to the to the centrifuge system for dewatering from the sludge. Advanced Membrane Technology-Ultra Filtration The treated Wastewater after Multi grade filter shall be passed through basket type strainer & then through the Ultra filtration skid. The permeate generated from the Ultra filtration shall be collected in UF permeate tank. The reject water, backwash water and fast flush water generated from the Ultra filtration shall be taken back to Wastewater collection tank.

Reverse Osmosis System The treated Wastewater from UF filtrate tank shall be pumped to Reverse Osmosis system. For adjusting the pH acid dosing system, dosing tank with & pumps will be provided prior to R.O. Block. To prevent passage of fine suspended solids to the RO membrane we shall be providing Micron Cartridge Filter. This filter will remove all suspended solids of size upto 5 micron. Reject generated from RO system shall be collected in RO reject tank from there it shall be pumped to thermal evaporator system. RO Reject Disposal System [Thermal Evaporation System] Thermal evaporation system shall be designed to hand rejects generated from RO system. Thermal Evaporator

The plant will bed specially designed for handling the RO Reject. Multiple Effect forced circulation Evaporation Plant with thermal vapour-compressor will be proposed to attain Zero discharge and recover water for recycling back to the plant and mix salt for solid waste disposal.

Sewage Treatment Plant

Generally the sewage Wastewaters will be generated only from canteen and toilets in the plant. In canteen, the wastewater will be collected in collection tank where the canteen wastes get settled down. The overflow from the collection tank will be taken for treatment. In toilets, the wastewater will be collected in Septic Tank and Soak pits from where the overflow will be taken for treatment. The Sewage generation for this operation will be 100 m3 /day and it will be treated in the sewage treatment plant.

 Aeration Tank

The Aeration tank will consist of a Bar screen, Six Tubular membrane Diffusers and two compartments of aeration unit. The air demand will be achieved by a Blower. The Wastewater enters the bar screen chamber where the coarse suspended solids will be separated. After screening, the sewage first flows upwards in the first compartment and then downwards in the second compartment. The tubular membrane diffusers will be placed at the bottom of the aeration tank to provide air in the aeration tank.  Secondary Clarifier

The biologically treated sewage will flow to a secondary clarifier, which is hopper bottom type.

 Chlorination Tank & Filter

The overflow from the clarifier will enter the Chlorination tank where it will be disinfected. The dosing will be done manually. Then the treated sewage

after disinfecting, will pass through a multigrade filter for polishing. The STP waste water characteristics are presented in Table-2.16

TABLE-2.16 WASTE WATER CHARACTERSTICS OF SEWAGE TREATMENT PLANT

Parameter Inlet Outlet pH 5.5 – 8.5 7 - 8 TSS (ppm) 200 < 5 COD (ppm) 550 < 20 BOD (ppm) 250 < 5 Temp (oC) 20 - 40 30 Flow (/Hr) 20 20

Annexure-3

Raw Water Requirement

ANNEXURE-3

WATER ALLOCATION LETTER FROM SIPCOT

TABLE 3.1 RAW WATER AT INTAKE POINT-RIVER TAMARABARINI

Sr. No. Parameters Quality 1. pH 8.4 2. Temperature 32oC 3. Conductivity 380 us/cm 4. Turbidity 1.9 NTU 5. Dissolved oxygen 7.2 mg/l 6. Total alakanity as CaCO3 78 mg/l 7. Total hardness as CaCO3 100 mg/l 8. Calcium hardness as CaCO3 70 mg/l 9. Chlorides as cl 38 mg/l 10. Sulphates as SO4 18 mg/l 11. Phosphates as PO4 0.01 mg/l 12. Nitrates as NO3 9.6 mg/l 13. Total Dissolved solids 275 mg/l 14. Chemical Oxygen Demand 42 mg/l 15. Sodium 14.4 mg/l 16. Potassium 3.0 mg/l

TABLE 3.2 COMPETING USERS OF THE WATER SOURCE Sr. Usage Present Consumption Addition Proposed Total No. (cu.m/day) as per local plan (cu.m/day)

Surface Ground Surface Ground Surface Ground 1 Irrigation 2109589 - - - 2109589 2 Industry 1328767 - - - 1328767 Drinking / 3 76320 107600 - 222500 76320 330100 township 4 Others ------Total 3514676 107600 - 222500 3514676 330100

Water Requirement –Copper Smelter Plant -II

The total water requirement of this project for Vedanta Limited is about 13324-m3/day. Out of this, fresh raw water requirement for entire operation of copper smelter is about 8773-m3/day and rest is met from treated Wastewater water and RO plants permeate. The details of usage and water balance is presented in Table-3.4 and shown in Figure-3.2.

TABLE-3.4 WATER REQUIREMENT – COPPER SMELTER PLANT –II OPERATION

All values are given in m3/day Sr. No. Purpose Water Consumption Wastewater Raw Recycled Generation (Fresh) Waste Water Water 1 Smelter Plant 2234 1005 950 2 Suphuric Acid Plant 3144 800 1744 3 Phosphoric Acid Plant 1673 1515 1250 4 Refinery, CCR & PMR 828 52 52 5 Wastewater Treatment Plant 493 1079 455 6 Domestic 190 0 100 7 Greenbelt 211 100 0 Total 8773 4551 4551

SIPCOT SUPPLY / DESALINATION PLANT/ MUNICIPAL SEWAGE treatment Treated Water 8773 M3 / day

2234 M3 3144 M3 1673 M3 828 M3 493 M3 190 M3 211 M3 + + + + + + 1005 M3 800 M3 1515 M3 52 M3 1079 M3 100 M3 SMELTER SAP PAP REFINERY, WWT DOMESTIC GREEN CCR & PMR P BELT

Wastewater 950 M3 1744 M3 1250 M3 52 M3 455 M3 100 M3 NIL Generation TREATMENT

TOTAL 4551 M3 / day

FIGURE-3.2 WATER BALANCE - COPPER SMELTER PLANT -II

Annexure-4

Raw Materials

ANNEXURE-4 Consumable Copper Smelter Plant -II (T/Day)

Smelter Copper concentrate (100% imported) 5061 Furnace oil 94 Liquid oxygen 1084 Silica 789 Quartz 173 Liquid Petroleum gas 30 High speed Diesel 3 Limestone 197 Coke 40 Refinery Hydrochloric acid 0.43 Thio-urea 2.55 Glue 2.55 Continuous Copper Rod Copper Cathode 800 Caustic Soda 0.01 ISO Propyl Alcohol 3.2 Emulsion 0.018 Wax 0.016 LPG/Propane 32 Sulphuric Acid Plant & WWTP Lime 217 Ferric sulphate 30 Sodium sulphide 20 Flocculent 0.03 Sodium Hydroxide 4 Phosphoric Acid Plant Suphuric acid (100%in–house production) 2229 Rock phosphate (100% imported) 3270 Active silica 31 Defoamer 4 Castic lye solution 1 Selenium Decopperised slime 5.5 Oxygen 1.06 Sulphur dioxide 2.8 DORE SMELTING Decopperised, Desellurised slime 4.92 Soda 0.6 Anhydrous Borax 0.6 Cement 0.02 Carbon 0.1 Copper Telluride recovery Electrolyte – CuSO4 142.8 Copper Shavings 1.02 Bismuth recovery Electrolyte – CuSO4 142.8 Sulphuric Acid 5.88

Annexure-5

Energy Requirements

ANNEXURE-5

Fuel/Energy Requirements A Total Power Requirement MVA Project Township Other Total (pl. specify) Copper 75 MW -- -- 75 MW Smelter – II B Source of Power (MVA) SEB/Grid Captive Power Plant DG Sets capacity (Co – generation from Waste heat boiler) Coal Based - *160 MW 7 MW Thermal Power Plant *Vedanta Limited has installed 160 MW capacity Thermal Power Plant (already approved by MOEF&CC) in Thoothukudi for Copper Smelter operation. C Details of Fuel used S. Fuel Daily Calorific Value No. Consumption (Kcals/Kg) net % Ash % Sulphur (TPD) on wet

1 Gas (LPG) 92 11800 - 0.02 2 Naphtha - - - - 3 HSD 6 12000 0.01 1 4 Fuel Oil 100 10500 0.01 3.0 HFO 5 Coal - - - - 6 Lignite - - - - 7 Other ( Coke) 80 5500 20 1

Annexure-6

Storage of Chemicals

ANNEXURE-6

CATEGORY WISE SCHEDULE OF STORAGE FACILITIES COPPER SMELER PLANT-II OPERTION

Sr. No. of Storage Capacity Classificati No. Material Tanks Copper Smelter Plant -II on Operation

1 H2SO4 (**) 7 5 x 10000 = 50,000 MT Corrosive 2 x 5000 = 10,000 MT 2 Fuel Oil (Furnace 2 2 x 800 = 1600 KL Flammable Oil) 3 HSD 2 2 x 100 = 200 KL Flammable 4 LPG 2 2 x 50 = 100 MT Flammable 5 Liquid Oxygen 4 2 x 220 MT LOX and Flammable 2 x 25 MT Lin 6 Coke 1 2500 MT - open storage Flammable 7 SO2 Gases in the 1 1 X 3 m Dia X 300 m length Toxic Duct leading to with 14% SO2 Gases to the Sulphuric acid plant equivalent of 775 MT of blower (*) 100 % SO2 3 8 H3PO4 5 4 x 5000 = 2000 M Corrosive 1 x 500 = 500 M3 3 9 H2SiF6 2 2 x 1000 = 2000 M 10 NaOH 3 1 x 20 = 20 MT Corrosive 2 x 15 = 30 MT

11 Na2S 2 2 x 22 = 44 MT Corrosive 12 Iso Propanal 1 1 X 23 = 23 MT Flammable Note: 1 (**) H2SO4 is the by-product from the process. 2 Fuel Oil (Furnace Oil) is used for Furnace fuel 3 HSD is used as start-up fuel for Sulphuric acid Plant preheater 4 LPG is used in furnace for metal refining and launder heating. 5 Liquid Oxygen is used as fuel for ISA Furnace along with fuel and air and oxy fuel burner of the RHF furnace is also consuming liquid oxygen. 6 Coke is used to control the magnetite level in the ISA furnace. 7 (*) SO2 Gases in the duct is released to the atmosphere during sudden trip of Sulphuric acid plant suction blower. 8 H3PO4 is the value added product from H2SO4 9 NaOH is used in tail gas scrubber. 10 Na2S is used in ETP -3. 11 Iso propanal is used in CCR pickling and quenching.

Annexure-7

Stack Emission Details

ANNEXURE-7

DETAILS OF STACK EMISSIONS- PROPOSED PLANT

Sr. Stacks Height Dia Temp Velocity Volu- No. Attached to meter metric flow m m  K m/s m3/Hr 1 ISA / RHF / SCF/ 165 3.0 338 17.7 832000 Converter/ Anode Furnaces 2 Sulphuric Acid Plant 165 3.0 332 13.7 390000 3 Phosphoric Acid 90 1.9 313 8.8 150000 Plant 4 Selenium plant 24 0.3 523 31.4 20000 5 Dore furnace stack 30 1 523 6.5 18500 6 CCR –Shaft furnace 15 1.0 523 3.5 10000