DOCSLIB.ORG

Smelting Reduction of Chromite Ore in an Oxygen Converter

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Smelting Reduction of Chromite Ore in an Oxygen Converter IZAWA, T., KATAYAMA, H., and SAND, N. Smelting reduction of chromite ore in an oxygen converter. INFACON 6. Proceedings ofthe 1st lIuematiOllal Chromium Steel alld Alloys Congress, Cape Towll. Volume 2. Johannesburg, SALMM, 1992. pp. 245-252. Smelting Reduction of Chromite Ore in an Oxygen Converter T. IZAWA*, H. KATAYAMAt, and N. SANO* * Research Association/or New Smelting Technologies, Tokyo, Japall tTechnical Development Bureau, Nippon Steel Corp., Tokyo, Japan tUniversity ofTokyo, Tokyo, Japan As electrical energy is more expensive in Japan than in other countries, technologies for decreasing the consumption of electrical energy in the processing of chromite ore to stainless steel have been developed. This paper describes the smelting reduction of chromite ore in the production of high-carbon ferrochromium, or the production of crude stainless steel in an advanced oxygen converter without the use of electrical energy as a heat source. Problems in the smelting reduction of chromite ore (i.e. slag foaming, reduction rate, post-combustion, lining erosion, and so on) can be solved simultaneously by a combination of the following conditions: (1) separation of the metal bath from the oxygen jet by a thick layer of slag and by an adequate blowing operation, and (2) control of the composition of slag as (MgO) + (AJ 20 3) = 45 to 46 per cent. Based on these principles, a pilot-plant test for the production of high-carbon ferrochrontium on a 5 1 scale (30 tid) was conducted successfully by lhe Research Association for New Smelting Technologics. Crudc stainless stcel is produced from dephosphorized pig iron and partially reduced chromite pellets by the smelting reduction process in a commercial top- and bottom-blowing converter. Introduction is decarburized by an oxygen jet, Figure I(a); that is, Conventionally, high-carbon ferrochrornium produced in an oxidizing reactions occur. On the other hand, if the metal electric furnace is used as a raw material in the production bath is separated from the oxygen jet by a thick layer of slag of chromium steel. In Japan, electrical energy is more containing a large amount of carbonaceous materials, it is expensive than in most other countries; therefore, the possible to proceed with reduction within the slag and to technology for the prereduction of chromite ore has been suppress the re-oxidation of the metal, Figure I(b). developed with the purpose of reducing the consumption of electrical energyl.2. In this decade, various research activities have been devoted to the production of high­ carbon ferrochromium or crude stainless steel by the smelting reduction of chromite ore in an advanced oxygen converter. Likewise, various technologies have been developed for the reduction of chromite ore without the use of electrical energy as a heat source. This paper describes these research activities and developmental work. The symbols used are defined at the end of the paper. Principle of the Process Recently, the top- and bottom-blowing converter has been used for steelmaking (Figure 1). In this furnace, the stirring (a) Steelmaking (b) Smelting reW::tion intensity of the molten metal and slag can be controlled by the blowing of gas through the bottom. In steelmaking with FIGURE I. Operation of the oxygen converter for steelmaking and relatively little slag (50 to 150 kglt of metal), the metal bath smelting reduction SMELTING REDUCTION OF CHROMlTE ORE IN AN OXYGEN CONVERTER 245 Before smelting reduction can proceed at high as fluoride or sodium compounds3 to the slag, by the productivity, il is imperative that those conditions which injection of fine chromium ore into a hot spot4.S• or by will stabilize a stirred bath be studied and quantified. For controlling the composition of the main components of the this purpose, the following problems have to be solved: slag (MgO, Si02, and CaO). Figure 3 shows an example of (I) how to suppress slag foaming the influence of slag composition on the reduction of (2) how to accelerate the reduction rate of chromite ore chromium oxide. In tl1is case, the addition of silica to the (3) how to increase the post-combustion ratio, slag accelerates the reduction of chromium oxide by allowing it to dissolve in the slag. The rate of the reduction %CO, depends on the composition of lhe metal, the viscosity of ( %CO + OkCO, x 100). the slag, the amount of carbonaceous materials, the to achieve the generation of sufficient heat temperature, and the stirring intensity. (4) how to suppress the erosion of the lining. Results of Fundamental Investigations In order to solve the problems outlined above, various 101 types of research studies have been conducted. 0 0 0 0 0 Suppression of Slag Foaming 0 ;;: In a conventional oxygen converter thal is used for the II making of steel, molten slag foams extensively, the apparent U .0. to ... density of the slag layer being less than 0,2 g/em'. If the ... .0. amount of slag increases under these conditions, stable O(SiO, )~301 operation of the converter is disturbed by an overflow or 6 ~351 0.11 0 ~401 'slopping' of the slag. The extent of slag foaming depends ... ~451 on the rale of CO generation and on the composition of the slag. However. il has been found that the presence of an 0 20 40 60 BO adequate amount of carbonaceous materials controls lhe timo (min) apparent density of the slag layer to a level of about 1,0 g/cm~, independent of the slag composition, as shown in FIGURE 3. Inl1uence of slag composition on the reduction of sIng Figure 2. This increase in density is due to the fact that containing chromium oxide by carbon in rocking furnace carbonaceous materials accelerate the release of CO gas by The rate formula can be expressed as follows: the coalescence of small bubbles generated by the reduction reactions. for (T. Cr) ;0, about 3 per cent, 1.2- d(T.Cr)_ k . 0' [I] .P"'---~-~'" d/ 1.0 '"ro P' ...a-Q. _ Vi , " for (T. Cr) < about 3 per cent. _"0.8- " o § I, ;:: " 0. 6 Co I 0, d(T. Cr) - k I {(T. Cr) - (T. Cr)r! . CIl 01 /, [2] t: - /0 kJ dt ~ 0.4 rr 1 0 1 The relationship between k I and the composition of the 0. 2 I- metal is shown in Figure 4. The rate constant k I decreases , with [%Cr], but levels off at chromium contents greater 0.1 0.2 than 20 per cent. This is so because, at lower chromium ° Coke/Slag (wt. ratio) levels, carbon in the metal contributes to the reduction of the chromium oxide but, with chromium contents higher than FIGURE 2. Effect of coke-to-slag ratio (by weight) on slag foaming 20 per cent, almost all the reduction occurs on the surface of the carbonaceous materials present in the molten slag. Acceleration of Chromite Ore Reduction Figure 5 shows the influence of the slag composition on Chromitc orc added to molten slag dissolves aL first, and the the overall rate constant in all experimenl in which argon chromium oxide in the slag is then reduced by carbon. The was inlroduced by bottom blowing without any top blowing dissolution of chromite ore is checked by the fonnalion of of oxygen, and the slag composition was conLrolled by the an insoluble spinel layer (MgO.AI20 3) around the ore addition of lime. The temperature of the metal bath was particles. The dissolution of the chromite ore can 1600 ±20°C and the slag was 0 to 100°C lower in consequently be accelerated by the addition of fluxes such temperature. The rate constant changes abruptly when the 246 INCSAC I c: 0.8 I 16000 e ..,0 u 12 :l "0 0.6 ..~ " 10 c: 0°,0" '" 'E .<: ~ 0.4 ~ 'c 8 \). ;;: ~ ';; 6 \'---0---- ~ 0.2 ::.e. '" a 0 0 r.,. ~ -.:-'" 4 - ...---ce__°-2.... u ~ a 20 40 60 80 100 2 (% C02) (%CO) + (%C0 )X 100 (%) oI:---'-_~':--'--:':_'----l'_-:';,-'--' 2 o 20 40 60 FIGURE 6. Effect of post-combustion on the chromium content of the ler] (%) slag in an oxygen converter with a thick layer of slag FIGURE 4. Effect of the chromium conteDl in the metal bath on the Increase in Post-combustion Ratio apparent rale constant, k1 To decrease the phosphorus input, the consumption of carbonaceous material should be decreased by an increase in the post-combustion ratio in the converter. The post­ 12 combustion ratio in a conventional oxygen converter for 16oo"C steelmaking is lower than 15 per cent. Nevertheless, 10 separation of the metal bath from the oxygen jet by a thick layer of slag is effective in increasing the post-combustion C B ratio while at the same time decreasing the formation of ! dust. This is shown in Figure 7. N 6 0 x x 4 2 0 30 60 (MgO) + IA',O,) (%) I, == 2 .... 4 kW!t 100 100 '"'E FIGURE 5. Effect of (MgO)) + (A120 3) content on the apparent rate ~ constant, k] i !!! ; c ~ 0 .E (MgO) + (Al 0,) content reaches 45 per cent. Ahove that ~ t: 2 ~ , critical value, the dissolution of chrornite is supposed to be 50 50 ." -g '0 suppressed. 0 C, ~ 0 On the other hand, in an experiment where top blowing of ~ 0 E oxygen was used, the temperature of the slag was almost CL 0 '" equal to that of the metal bath. Then the critical value of 0 0.7 1 2 3 Ls/Lso (-1 (MgO) + (A1 20,) was about 46 per cent at 1600°C. Therefore, the dissolution of chromite ore and the reduction FIGURE 7. Relationship between post-combustion and Ls/Lso in an of chromium oxide can be accelerated if (MgO) + (AI 20,) is oxygen converter less than the critical value, and this can be achieved by the addition of lime to the slag.
Load more

Recommended publications
  • Effects of Varied Process Parameters on Froth Flotation Efficiency: a Case Study of Itakpe Iron Ore
    Nigerian Journal of Technology (NIJOTECH) Vol. 39, No. 3, July 2020, pp. 807 – 815 Copyright© Faculty of Engineering, University of Nigeria, Nsukka, Print ISSN: 0331-8443, Electronic ISSN: 2467-8821 www.nijotech.com http://dx.doi.org/10.4314/njt.v39i3.21 EFFECTS OF VARIED PROCESS PARAMETERS ON FROTH FLOTATION EFFICIENCY: A CASE STUDY OF ITAKPE IRON ORE S. Akande1, E. O. Ajaka2, O. O. Alabi3 and T. A. Olatunji4,* 1, 2, DEPARTMENT OF MINING ENGINEERING, FEDERAL UNIV. OF TECHNOLOGY, AKURE, ONDO STATE, NIGERIA 3, 4, DEPT. OF MET. & MATERIALS ENGINEERING, FEDERAL UNIV. OF TECHNOLOGY, AKURE, ONDO STATE, NIGERIA Email addresses: 1 [email protected], 2 [email protected], 3 [email protected], 4 [email protected] ABSTRACT The dire need for Itakpe iron ore concentrates of appreciable iron content meets for smelting operation necessitated this study. Core samples of the iron ore sourced from Itakpe, Kogi State, Nigeria were prepared for petrological analysis followed by chemical and particle size analyses. Froth flotation was done using different collectors at varying particle sizes and pH values. Characterization studies carried out revealed that Itakpe iron ore is a lean ore assaying 36.18% Fe2O3 and contains predominantly quartz, sillimanite, and haematite. Its liberation size lies favourably at 75 µm. Processing the ore by froth flotation yielded appreciable enrichment. Optimal recovery (~92%) was achieved using potassium amyl xanthate (PAX) at pH 11 for fine feed sizes (<125 µm) yielding iron concentrate assaying 67.66% Fe2O3. Thus, processing at this set-of- conditions is recommended for the industrial production of more enriched Itakpe iron ore concentrates.
    [Show full text]
  • Principles of Extractive Metallurgy Lectures Note
    PRINCIPLES OF EXTRACTIVE METALLURGY B.TECH, 3RD SEMESTER LECTURES NOTE BY SAGAR NAYAK DR. KALI CHARAN SABAT DEPARTMENT OF METALLURGICAL AND MATERIALS ENGINEERING PARALA MAHARAJA ENGINEERING COLLEGE, BERHAMPUR DISCLAIMER This document does not claim any originality and cannot be used as a substitute for prescribed textbooks. The information presented here is merely a collection by the author for their respective teaching assignments as an additional tool for the teaching-learning process. Various sources as mentioned at the reference of the document as well as freely available material from internet were consulted for preparing this document. The ownership of the information lies with the respective author or institutions. Further, this document is not intended to be used for commercial purpose and the faculty is not accountable for any issues, legal or otherwise, arising out of use of this document. The committee faculty members make no representations or warranties with respect to the accuracy or completeness of the contents of this document and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. BPUT SYLLABUS PRINCIPLES OF EXTRACTIVE METALLURGY (3-1-0) MODULE I (14 HOURS) Unit processes in Pyro metallurgy: Calcination and roasting, sintering, smelting, converting, reduction, smelting-reduction, Metallothermic and hydrogen reduction; distillation and other physical and chemical refining methods: Fire refining, Zone refining, Liquation and Cupellation. Small problems related to pyro metallurgy. MODULE II (14 HOURS) Unit processes in Hydrometallurgy: Leaching practice: In situ leaching, Dump and heap leaching, Percolation leaching, Agitation leaching, Purification of leach liquor, Kinetics of Leaching; Bio- leaching: Recovery of metals from Leach liquor by Solvent Extraction, Ion exchange , Precipitation and Cementation process.
    [Show full text]
  • A Study on Reduction of Copper Smelting Slag by Carbon for Recycling Into Metal Values and Cement Raw Material
    Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 17 January 2020 doi:10.20944/preprints202001.0177.v1 Peer-reviewed version available at Sustainability 2020, 12, 1421; doi:10.3390/su12041421 Article A Study on Reduction of Copper Smelting Slag by Carbon for Recycling into Metal Values and Cement Raw Material Urtnasan Erdenebold and Jei-Pil Wang* Department of Metallurgical Engineering, School of Engineering, Pukyong National University, Busan 608- 739, Korea * Correspondence: [email protected]; Tel,: +82-51-629-6341 Abstract: Copper smelting slag is a solution of molten oxides created during the copper smelting and refining process, and about 1.5 million tons of copper slag is generated annually in Korea. Oxides in copper smelting slag include ferrous (FeO), ferric oxide (Fe2O3), silica (SiO2 from flux), alumina (AI2O3), calcia (CaO) and magnesia (MgO). Main oxides in copper slag, which iron oxide and silica, exist in the form of fayalite (2FeO·SiO2). Since the copper smelting slag contains high content of iron, and copper and zinc. Common applications of copper smelting slag are the value added products such as abrasive tools, roofing granules, road-base construction, railroad ballast, fine aggregate in concrete, etc., as well as the some studies have attempted to recover metal values from copper slag. This research was intended to recovery Fe-Cu alloy, raw material of zinc and produce reformed slag like a blast furnace slag for blast furnace slag cement from copper slag. As a results, it was confirmed that reduction smelting by carbon at temperatures above 1400°С is possible to recover pig iron containing copper from copper smelting slag, and CaO additives in the reduction smelting assist to reduce iron oxide in the fayalite and change the chemical and mineralogical composition of the slag.
    [Show full text]
  • Nickel Laterite Smelting Processes and Some Examples of Recent Possible Modifications to the Conventional Route
    metals Review Nickel Laterite Smelting Processes and Some Examples of Recent Possible Modifications to the Conventional Route Ender Keskinkilic Department of Metallurgical and Materials Engineering, Atilim University, 06830 Ankara, Turkey; [email protected]; Tel.: +90-533-302-9510 Received: 16 July 2019; Accepted: 1 September 2019; Published: 3 September 2019 Abstract: The treatment of laterites has been a research hotspot in extractive metallurgy over the past decades. Industrially, the pyrometallurgical treatment of laterites is mostly accomplished with a well-established method, namely, the rotary kiln–electric arc furnace (RKEF) process, which includes three main operations—calcination, prereduction, and smelting—followed by further refining for the removal of impurities from the raw ferro-nickel. As indicated in many studies of the RKEF process, the major downside of this method is its high energy consumption. Efforts have been made to lower this consumption. Furthermore, several new processes have been proposed. Among these, low-grade ferro-nickel production is regarded as the most widely and industrially used process after traditional RKEF operation. Although not widespread, other alternative processes of industrial scale have been generated since the start of the millennium. Recently, certain innovative processes have been tested either in the laboratory or at pilot-scale. In this paper, a literature review related to the smelting of laterites is made, and an emphasis on new processes and some examples of new developments in the RKEF process are presented. Keywords: laterite; smelting; RKEF process; low-grade ferro-nickel 1. Introduction According to a review published by Diaz et al., oxide-type nickel ores accounted for 64% of land-based nickel ores, but more than 60% of nickel production was based on the matte smelting of sulfide ores in 1988 [1].
    [Show full text]
  • Integral Management of Arsenical Sludge, Treatment and Recovery of By-Products of Acid Waters from Smelter Plants
    MILAF: INTEGRAL MANAGEMENT OF ARSENICAL SLUDGE, TREATMENT AND RECOVERY OF BY-PRODUCTS OF ACID WATERS FROM SMELTER PLANTS ULRIKE BROSCHEK, CECILIA VIDAL, LUIS BRAVO and GILDA ZUÑIGA Environmental Program, Fundación Chile Parque Antonio Rabat Sur 6165, Vitacura, Santiago, Chile; E-mail: [email protected] ABSTRACT Currently, the copper mining industry produces high amounts of sulfuric acid with low purity and high concentrations of arsenic and other metals. Most of these acid waters are neutralized in the copper smelting plants by using lime to raise the pH from 1 to 12 generating high amounts of arsenical sludge that has to be disposed on safety landfills because of its high toxicity. This has forced the mining companies to pay large sums of money for the disposal of significant volume of solid waste. Each copper smelting plant produces in average during this specific process more than 18,000 tons of arsenical sludge yearly, spending on the treatment and disposal stage more than US 2.8 million dollars per year where a 70 % of this cost corresponds to the disposal costs of the solid waste [1,2,3]. Different technologies for treating these acid wastewaters have been developed and patented worldwide. However, these treatments have focused on obtaining the separation of the arsenic from the effluent through physical-chemical precipitation using different basic components and cations that reacts with the contaminants and then precipitates in the solution [4]. These technologies have not been able to solve the problem because they are expensive, complex, not always efficient and still generates high amounts of arsenical sludge requiring high disposal costs; hence, mining companies have not implement them.
    [Show full text]
  • National Emissions Standards for Hazardous Air Pollutants from Secondary Lead Smelting; Final Rules
    Vol. 77 Thursday, No. 3 January 5, 2012 Part II Environmental Protection Agency 40 CFR Part 63 National Emissions Standards for Hazardous Air Pollutants From Secondary Lead Smelting; Final Rules VerDate Mar<15>2010 16:35 Jan 04, 2012 Jkt 226001 PO 00000 Frm 00001 Fmt 4717 Sfmt 4717 E:\FR\FM\05JAR2.SGM 05JAR2 mstockstill on DSK4VPTVN1PROD with RULES2 556 Federal Register / Vol. 77, No. 3 / Thursday, January 5, 2012 / Rules and Regulations ENVIRONMENTAL PROTECTION related to emissions during periods of the telephone number for the Air and AGENCY startup, shutdown, and malfunction. Radiation Docket and Information DATES: This final action is effective on Center is (202) 566–1742. 40 CFR Part 63 January 5, 2012. The incorporation by FOR FURTHER INFORMATION CONTACT: For [EPA–HQ–OAR–2011–0344; FRL–9610–9] reference of certain publications listed questions about this final action, contact in the rule is approved by the Director RIN 2060–AQ68 Mr. Nathan Topham, Office of Air of the Federal Register as of January 5, Quality Planning and Standards, Sector 2012. National Emissions Standards for Policies and Programs Division, U.S. ADDRESSES: Hazardous Air Pollutants From The EPA has established a Environmental Protection Agency, Secondary Lead Smelting docket for this action under Docket ID Research Triangle Park, NC 27711; No. EPA–HQ–OAR–2011–0344. All telephone number: (919) 541–0483; fax AGENCY: Environmental Protection documents in the docket are listed on number: (919) 541–3207; and email Agency (EPA). the http://www.regulations.gov Web address: [email protected]. For ACTION: Final rule. site.
    [Show full text]
  • The Metallurgy of Antimony
    Chemie der Erde 72 (2012) S4, 3–8 Contents lists available at SciVerse ScienceDirect Chemie der Erde journal homepage: www.elsevier.de/chemer The metallurgy of antimony Corby G. Anderson ∗ Kroll Institute for Extractive Metallurgy, George S. Ansell Department of Metallurgical and Materials Engineering, Colorado School of Mines, Golden, CO 80401, United States article info abstract Article history: Globally, the primary production of antimony is now isolated to a few countries and is dominated by Received 4 October 2011 China. As such it is currently deemed a critical and strategic material for modern society. The metallurgical Accepted 10 April 2012 principles utilized in antimony production are wide ranging. This paper will outline the mineral pro- cessing, pyrometallurgical, hydrometallurgical and electrometallurgical concepts used in the industrial Keywords: primary production of antimony. As well an overview of the occurrence, reserves, end uses, production, Antimony and quality will be provided. Stibnite © 2012 Elsevier GmbH. All rights reserved. Tetrahedrite Pyrometallurgy Hydrometallurgy Electrometallurgy Mineral processing Extractive metallurgy Production 1. Background bullets and armory. The start of mass production of automobiles gave a further boost to antimony, as it is a major constituent of Antimony is a silvery, white, brittle, crystalline solid that lead-acid batteries. The major use for antimony is now as a trioxide exhibits poor conductivity of electricity and heat. It has an atomic for flame-retardants. number of 51, an atomic weight of 122 and a density of 6.697 kg/m3 ◦ ◦ at 26 C. Antimony metal, also known as ‘regulus’, melts at 630 C 2. Occurrence and mineralogy and boils at 1380 ◦C.
    [Show full text]
  • The Advanced Mining Technologies and Its Impact on the Australian Nonferrous Minerals Industry
    Paper Title: PROVEN TECHNOLOGIES FROM XSTRATA AND THEIR APPLICATIONS FOR COPPER SMELTING AND REFINING IN CHINA Paper Presented at: Hainan Conference, China Authors: Mingwei Gao, Philip Arthur and Nigel Aslin, Xstrata Technology Date of Publication: 2004 For further information please contact us at [email protected] www.isasmelt.com PROVEN TECHNOLOGIES FROM XSTRATA AND THEIR APPLICATIONS FOR COPPER SMELTING AND REFINING IN CHINA Mingwei Gao, Philip Arthur and Nigel Aslin Xstrata Technology, Australia 1.0 INTRODUCTION The world’s non-ferrous industry has achieved significant improvements in efficiency in the last 20 years owing to the advanced technologies such as ISASMELT™ and ISA PROCESS that have been invented and developed at Mount Isa Mines in Australia,. A number of large nonferrous mining operations in the world are still in business today largely because of the commercial benefits that resulted from applying these technologies. ISASMELT and ISA PROCESS technologies are marketed worldwide by Xstrata Technology, a division of the Xstrata plc group of companies, which was formed upon Xstrata’s takeover of MIM Holdings Limited in mid 2003. Xstrata PLC is a diversified international mining company and has operations in Australia, the United Kingdom, Germany, Spain, South Africa, Chile, and Argentina with around 20,000 employees worldwide. Major products are copper, lead, zinc, silver, coal, ferrochrome, and ferrovanadium. In addition to these commodities, an integral part of the group is their independent process technology business – Xstrata Technology. Xstrata group companies have a long record of developing process technologies for in-house use and for sale to external clients. 2.0 ISASMELT™ TECHNOLOGY ISASMELT is a modern bath-smelting process for the production of non-ferrous metals.
    [Show full text]
  • Metal Losses in Pyrometallurgical Operations - a Review
    Advances in Colloid and Interface Science 255 (2018) 47–63 Contents lists available at ScienceDirect Advances in Colloid and Interface Science journal homepage: www.elsevier.com/locate/cis Historical perspective Metal losses in pyrometallurgical operations - A review Inge Bellemans a,⁎, Evelien De Wilde a,b, Nele Moelans c, Kim Verbeken a a Ghent University, Department of Materials, Textiles and Chemical Engineering, Technologiepark 903, B-9052, Zwijnaarde, Ghent, Belgium b Umicore R&D, Kasteelstraat 7, B-2250 Olen, Belgium c KU Leuven, Department of Materials Engineering, Kasteelpark Arenberg 44, bus 2450, B-3001, Heverlee, Leuven, Belgium article info abstract Article history: Nowadays, a higher demand on a lot of metals exists, but the quantity and purity of the ores decreases. The Received 24 October 2016 amount of scrap, on the other hand, increases and thus, recycling becomes more important. Besides recycling, Received in revised 4 August 2017 it is also necessary to improve and optimize existing processes in extractive and recycling metallurgy. One of Accepted 7 August 2017 the main difficulties of the overall-plant recovery are metal losses in slags, in both primary and secondary Available online 10 August 2017 metal production. In general, an increased understanding of the fundamental mechanisms governing these losses could help further improve production efficiencies. This review aims to summarize and evaluate the current sci- Keywords: fi Pyrometallurgy enti c knowledge concerning metal losses and pinpoints the knowledge gaps. Metal losses First, the industrial importance and impact of metal losses in slags will be illustrated by several examples from Slags both ferrous and non-ferrous industries.
    [Show full text]
  • Flotation of Sulphide Ores - HZL Experience
    FROTH FLOTATION : RECENT TRENDS @IIME, JAMSHEDPUR, 1998; pp. 18-41 Flotation of Sulphide Ores - HZL Experience V.P. KOHAD Hindustan Zinc Ltd., Zawar Mines, Udaipur - 313 901 ABSTRACT Flotation process, patented in the year 1906, was originally developed for mineral industry to recover values from high grade tailings of gravity separation plants. This technology has acclaimed importance as a versatile process for the beneficiation of vast variety of sulphide minerals. Due to flexibility of the process and remarkable development taken place in flotation technology and its ancillary systems, it has now become possible to recover fine grained sulphide minerals from complex ore deposits, whose processing was earlier considered un- economical. Today, about 400 million tonnes of sulphide ore is treated annually by flotation process worldwide. M/s Hindustan Zinc Ltd. (HZL), a leading lead-zinc mining and smelting company in India has experienced a spectacular growth from the time of its inception. Starting from a single 500 MT per day lead-zinc mine at Zawar, HZL has expanded its mining capacity to about 13,000 MT per day with matching ore beneficiation plants, all adopting froth flotation technology. The phenomenal progress is a result of HZL's emphasis on research and development with an objective to improve the efficiency and to optimize performance, and to seek innovative modern technology and control systems in their flotation plant and processes. This has not only solved metallurgical problems but improved overall plant economics. High grade concentrates produced with reduced deleterious impurities have further enhanced smelting efficiency. The paper covers general principles and aspects of industrial sulphide ore flotation practices in brief and processes adopted in HZL's plants.
    [Show full text]
  • Remanded Smelting Wastes
    REMANDED SMELTING WASTES Technical Background Document Office of Solid Waste U.S. Environmental Protection Agency December 1995 TABLE OF CONTENTS INTRODUCTION .........................................................................................................................1 1.0 BACKGROUND ...............................................................................................................1 1.1 Exclusion of Mining Wastes from RCRA Regulation ..........................................3 1.2 Development of a Narrower Interpretation of the Mining Waste Exclusion .........3 1.3 Reversion to the 1980 Interpretation of the Mining Waste Exclusion ..................4 1.4 Court Challenges to the Broad Interpretation .......................................................4 1.5 Court Challenges to the Re-Listing ......................................................................4 2.0 INDUSTRY OVERVIEW ...................................................................................................5 2.1 Description of Facilities Generating Wastes ........................................................5 2.2 Description of Industrial Processes and Waste Management .............................6 3.0 BASIS FOR THE NO-LIST DECISION ...........................................................................13 4.0 SUMMARY OF FINDINGS ..............................................................................................14 BIBLIOGRAPHY APPENDICES A. Rissmann Trip Report B. Magma and Cyprus Trip Report C. Letter from Benito Garcia,
    [Show full text]
  • Form -1 Environmental Clearance for Copper
    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.
    [Show full text]