Pre-Feasibility Report for Addition of Wet Screening System to Blast Furnace & DRI for Iron Ore Processing
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Pre-feasibility Report for addition of Wet Screening System to Blast Furnace & DRI for Iron Ore Processing. Increase in BlastPRE Furnace- capFEASIBILITYacity from 1,75,000 to 2,50,000TPA of M/sREPORT Visa Steel Limited At- Kalinga nagar Industrial Complex, Jajpur, Odisha. Addition of Iron Ore Washing & Wet Screening System for Rainy Period 1x 50 TPH (1350 TPD Throughput-for BF feed) & 1x58.3 TPH (1600 TPD Throughput-for DRI feed) & Increase in Hot Metal production capacity from 175000 TPA to 250000 TPA without change in Size for Existing Blast Furnace At Kalinganagar Industrial Complex, Jajpur, Odisha Applicant M/s Visa Steel Limited Kalinga nagar Industrial Complex, Jajpur, Odisha. M/s VISA STEEL LIMITED Page 1 Pre-feasibility Report for addition of Wet Screening System to Blast Furnace & DRI for Iron Ore Processing. Increase in Blast Furnace capacity from 1,75,000 to 2,50,000TPA of M/s Visa Steel Limited At- Kalinga nagar Industrial Complex, Jajpur, Odisha. CHAPTER – 1 EXECUTIVE SUMMARY Presently M/s VISA Steel Limited (VSL) is operating a 0.5 MTPA integrated steel plant at Kalinganagar Industrial Complex in Odisha. The facilities include a 175000 TPA Pig Iron Plant, 300,000 TPA Sponge Iron Plant, 500,000 TPA Steel Melt Shop (with EAF, LRF and VD) & 500,000 TPA Rolling Mill (Bar & Wire Rod Mill). VISA Steel is also operating 125000 (VISA Steel-50000 & VISA Bao-75,000 TPA) Ferro Chrome Plant and a 75 MW Captive Power Plant. Previous EC was obtained for 1.5 MTPA integrated steel plant withAn CPPnexure vide– Ifile no. J- th 11011/33/2007/IA-II(I), dated 12 June 2007 (Copy attached as ) and for expansion of integrated steel plant by addition of Rolling Mill (1.5 MTPA) with CPPAnnexure (256 MW)– rd videII file no. J-11011/1000/2007/IA-II (I), dated 3 July 2008 (Copy attached as th ). Amendment to EC for changeAnnexure in configuration–III of Captive Power Plant was obtained on 5 March 2011 (Copy attached as ). Annexure-IV A detailed statement for existing & proposed is attached as . IRON ORE WASHING & WET SCREENING SYSTEM FOR BLAST FURNACE The purpose of a blast furnace is to chemically reduce and physically convert iron oxides into liquid iron called "hot metal". The blast furnace is a huge, steel stack lined with refractory brick, where iron ore, coke and limestone are dumped into the top, and preheated air is blown into the bottom. The raw materials require 6 to 8 hours to descend to the bottom of the furnace where they become the final product of liquid slag and liquid iron. These liquid products are drained from the furnace at regular intervals. The hot air that was blown into the bottom of the furnace ascends to the top in 6 to 8 seconds after going through numerous chemical reactions. Iron oxides can come to the blast furnace plant in the form of raw ore, pellets or sinter. The raw ore is removed from the earth and sized into pieces that range from 0.5 to 1.5 inches. This ore is either Hematite (Fe2O3) or Magnetite (Fe3O4) and the iron content ranges from 50% to 70%. This iron rich ore can be charged directly into a blast furnace without any further M/s VISA STEEL LIMITED Page 2 Pre-feasibility Report for addition of Wet Screening System to Blast Furnace & DRI for Iron Ore Processing. Increase in Blast Furnace capacity from 1,75,000 to 2,50,000TPA of M/s Visa Steel Limited At- Kalinga nagar Industrial Complex, Jajpur, Odisha. processing. Iron ore that contains a lower iron content must be processed or beneficiated to increase its iron content. The physical quality of Iron ore varies depending upon the season while being excavated from mines, sized as per customer requirement, transportation and handling at RMHS of the steel manufacturing plant. BF requires sized and dry iron ore with no fines attached for quick and healthy reduction to hot metal Iron. During non-monsoon Iron ore remains dry hence fines are easily screened out and requisite sized Iron ore are fed to BF by conveyor means. However screening process becomes a cumbersome task during monsoon season due to sticky nature of Iron ore which comes with fines sticked to it. Hence to obtain Iron ore free from sticky fines, VSL-BF has planned a project for Wet screening of Iron ore and storage of fines generated after wet screening as pollution control measures. This iron ore wet screening system will be in operation only during rainy season to separate out sticky fines from the ore. IRON ORE WASHING & WET SCREENING SYSTEM FOR DIRECT REDUCED IRON The purpose of a DRI is to chemically reduce and physically solid to solid convert iron oxides into free solid iron called "Sponge Iron". The DRI kilns are horizontal cylindrical steel stack lined with refractory cas table materials lining, where iron ore, non-cocking coal and Dolomite fed to inlet of kiln. The raw materials require 18 to 20 hours to complete the chemical reaction inside kiln & indirect cooling at cooler to discharge as mixture of DRI and Char. This cooled discharged materials passes through magnetic separators where it becomes the final product of DRI Lumps & DRI Fines. These DRI products are keeping bagged ready to dispatch. Iron oxides can come to the DRI plant in the form of raw ore or pellets. The raw ore is removed from the earth and sized into pieces that range from 0.5 to 1.5 inches. This ore is either 2 3 Hematite (Fe O ) or Magnetite (Fe3O4) and the iron content ranges from 50% to 70%. Only Hematite iron rich ore can be charged by converting to size of 4 mm to 22 mm with Coal & Dolomite to DRI Kiln. Iron ore that contains a lower iron content must be processed or beneficiated to increase its iron content. The physical quality of Iron ore varies depending upon the season while being excavated from mines, sized as per customer requirement; transportation and handling at RMHS of the steel manufacturing plant. For consistent production, sized and dry iron ore with no fines attached required for quick and healthy reduction. During non-monsoon Iron ore remains dry hence fines are easily screened out and requisite sized Iron ore fed to DRI Kilns. However screening process becomes a cumbersome task during monsoon season due to sticky nature of Iron ore which M/s VISA STEEL LIMITED Page 3 Pre-feasibility Report for addition of Wet Screening System to Blast Furnace & DRI for Iron Ore Processing. Increase in Blast Furnace capacity from 1,75,000 to 2,50,000TPA of M/s Visa Steel Limited At- Kalinga nagar Industrial Complex, Jajpur, Odisha. comes with fines sticked to it. Hence to obtain Iron ore free from sticky fines, VSL-DRI has planned a modification in existing screening circuit for washing of Iron ore, reuse of water and storage of fines (-4 mm size) generated after washing to complies pollution control measures. This iron ore system will be in operation only during rainy season to separate out sticky fines from the ore.WASHING & WET SCREENING SECTION 1x 50 TPH (1350 TPD Throughput-for BF feed) & 1x58.3 TPH (1600 TPD Throughput-for DRI feed) AIR POLLUTION CONTROL EQUIPMENT The entire process is a wet process starting from input of raw iron ore to output of washed & screened iron ore. No air pollution envisaged during operation as no ETP DETAIL AND SOLID WASTE MANAGEMENT emission of fines due to rain and high moisture of iron fines. Iron fines slurry when dumped into slurry tank to be treated with Chemical to avoid contamination of water flowing to the next stage. Clear water is collected at last sump which is to be pumped again for spraying/washing of iron ore at on-line screens. With respect to Iron fines storage tank, very small quantity of water with iron fines is required to be shifted to existing settling tank and its clear water will be sent to existing thickener of GCP. The settled fines will be again shifted to iron fines storage WATER REQUIREMENT & CONSUMPTION tank with the help of JCB/ Excavator. Initially water requirement is 240 Mᶾ. Above process to be operated with the recirculation of water through the piping & ETP. There is no much water loss in the entireWASTE process WATER, only GENERATION approx. 60 KLD FROM will beEACH the SOURCE,make-up waterTREAT requirement.MENT, RE-USE AND QUANTITY TO BE DISCHARGED WITH DISCHARGE POINTS Primarily, Water to be collected at following points after washing of Iron ore; 1. At sump S7 from where clean water to be directly reused for spraying at existing on-line screen (Refer process flow chart of iron ore washing). 2. At Pit from where water with slight amount of iron fines to be pumped to sump S11 (Refer process flow chart of iron ore washing). On effluent treatment clean water to be re-used at existing Thickener of GCP and settled fines to be shifted 3. again at sumps S8, S9 and S10. There will be no any discharge of water in the drain and no solid waste 4. generation from the process of iron ore washing system. Total 350 TPD tailings/fines will be generated and will be stored in the fines storage tank of size 21m x 7 m x 2 m. for DRI & 33m x 3 m x 1 m. The solid waste will be further collected at iron ore fines yard. M/s VISA Steel Limited (VSL) had installed the existing Blast Furnace (BF) Plant in May 2005 and later on forward integration to steel making through the route of Blast Furnace, M/s VISA STEEL LIMITED Page 4 Pre-feasibility Report for addition of Wet Screening System to Blast Furnace & DRI for Iron Ore Processing.