Metal prices have been rising since 2003. During 2003-2006, gold & aluminum prices became two times higher, and copper & zinc prices 4∼5 times higher. In particular, 2006 prices were skyrocketing, and the comparison of selected metal prices between 2005 and 2006 indicates steep rise; zinc (236%), copper (183%), nickel (165%), gold (136%) and aluminum (135%). The current higher metal prices are supported by expanding metal demands by BRICs countries (Brazil, Russia, China and India), and inflow of speculative market into mineral commodities. The current higher metal prices have a great influence on non-ferrous metals industry, and is creating several issues from the viewpoint of countries, corporation, and stake holders. This paper includes (1) current soaring prices of non-ferrous metals, (2) impact of higher metal prices on world major companies and (3) influences of current world mining business on Japanese smelting companies. Along with the soaring metal prices during 2003-2007, world major mining companies (Majors) rose record of high level profits particularly in 2006, which promoting M & A (Merger and Acquisition), and/or higher convergence of Majors. The analysis of influences of world mining trends on Japanese smelting companies will be summarized as is shown below; (1) M & A brought the higher convergence of Majors. For example, copper mining production rates by best 5 companies rose from 32% in 1990 to 41% in 2006. (2) Under the competitive copper concentrate market due to the emergence of China, Japanese smelting companies are confronting with difficulties in TC/RC (Treatment Charge and Refining Charge) negotiations with Majors such as BHP Billiton.
Present status and issues of non-ferrous extractive metallurgy were described in this short review from resource and environmental points of view. Recent trend of shortage of non-ferrous ores and severe regulations gave several impacts to non-ferrous extractive metallurgical industry, although significant innovations of non-ferrous extractive metallurgical processes have not been done in this decade. There are three big issues in the society. The first one is how to control iron, sulfur and minor impurities like arsenic. Sulfur is over supplied in the world, then more than 10 millions tons sulfur are stored near oil and natural gas refineries. Therefore, a development of new application of sulfur is still essential. Usage of slag is also big problem. Since regulations on the usage of slag became severe, we have to change a mind that slag is not a sink of minor impurities but an important by-product containing iron which is major impurity in non-ferrous ores. Good collaboration of each non-ferrous smelter and refinery will be required to keep them in Japan to treat not major non-ferrous metals but harmful minor elements like arsenic and cadmium. Keeping non-ferrous industry is one of keys to achieve the sustainable development in Japan.
This paper describes the outline of comminution and separation technology for creating the “Sound Material Circulation Society”. In especial, the importance of such technology was emphasized by introducing the “3R” concept. Improving mechanism of the liberation of compositional materials in comminution process, properties of two kinds of separation technologies, soft and hard separations, applicable size range for soft separation, adequate combination flow of separation technologies, and evaluation method of separation results were introduced.
The purpose of this article is to analyze recycling of used materials with resource potential as well as pollution potential from a viewpoint of environmental economics. It surveys the present circumstances of material and resource circulation, and shows how smooth recycling can be promoted in a market economy if it is supported by a formal regime of material circulation. In such a material circulating economy, resource potential of residuals which have once been treated as waste is realized as real market value, while their pollution potential is not realized. It is also demonstrated that promotion of recycling extends the life of landfill on one hand, and reduces the price of used materials on the other. An increase in the foreign demand for waste materials tends to arrest their price reduction. Yet, it is anticipated that recycling of waste materials in developing countries can not afford to deter their pollution potential, and may possibly diffuse real pollution.
The current flow of international trade of recyclable waste and secondhand goods are reviewed. China is a major importer of metal scraps in Asia. Hazardous wastes are also traded for recovering metals. There are several problems related to international trade of recyclable waste. Some of wastes are recycled without environmentally sound technology, causing pollution problems. Some hazardous wastes or non-recyclables are exported for disposal, under the name of recyclables. On the other hand, the regulations to control international trade become a barrier to the activity of good recyclers, who comply the regulation, because the formal procedure to export and import hazardous waste takes a long time before shipment. To encourage the sound-material circulation society in Asia, it is important to tighten the enforcement of the Basel Convention, and to reduce the too high barrier for transboundary movement destined for recyclers with environmentally sound technologies.
Kosaka smelter started copper production in 1901 using blast furnace, and diversified into other products and metallurgical technologies that treated complex concentrates produced at black ore mine. Black ore is complex sulfide ore containing many valuable metals such as copper, zinc, lead, gold and silver. And main processes are composed of copper operation that consist of flash smelting furnace and PS converter, and lead operation using hydrometallurgical treatment plant and electric furnace. However, social and economical situation changed worldwide in recent year, domestic black ore mines closed one after another and last black ore mine closed in 1994. But complex nature of black ore has made the capabilities to treat large variety of low materials and complex concentrate. And Kosaka smelter started restructuring measure to cope with this harsh business environment. The cores of the plan were improving the performance of complex smelting technologies to precious metal production and expansions to recycling business and waste management business. This paper introduces recent copper operation and describes about an outline of the modification.
Copper smelting with green charged reverberatory furnaces has been operated since 1965 at Onahama Smelter and Refinery. Recycling business has been progressed during the last decade as well as many improvements for copper smelting and refining process. Shredder residue derived from automobile scrap and others, has been treated in the reverberatory furnaces at 140,000 t per year recently.
Hitachi refinery of Nikko Smelting & Refining Co. Ltd. changed its operation scheme by introducing the ISA permanent cathode technology for the first time in Japan in December 2002. The change resulted in higher productivity, better cathode quality and lower operational costs. The operation has been continuously improved to reach a 20% higher production capacity than the original one. For the electrolyte purification process, the Hitachi refinery introduced a sulfuration process in April 2001. This process removed sulfide (As, Sb and Bi) formed by the reaction of hydrogen sulfide from electrolyte with increasing in production of copper cathode by partially eliminating liberator cells.
Tamano Smelter & Refinery of Hibi Kyodo Smelting Co., Ltd. started its operation in January, 1972. The production capacity of electrolytic copper has gradually increased and it reaches 260,000t/y now. In the last decade, 2 times production expansions were executed in order to achieve further cost saving and high production efficiency. This paper describes the various developments which were commissioned during the decade.
The Mitsubishi Naoshima Smelter & Refinery started copper smelting operation in 1917, since then has been developed smelting and refining technologies like Mitsubishi Process, which is an efficient, pollution free continuous copper smelting and converting process. At present, Naoshima Smelter & Refinery has three major activities; copper business, precious metals business and recycling business. In this decade, Naoshima Smelter & Refinery has been utilized the copper smelting technology for recycling business, which consists of the treatment of the industrial wastes and the treatment of copper and/or precious metal-bearing materials. Two recycling plants were constructed as pre-treatment plants for Mitsubishi process. One is the incinerating and melting plant, and the other is washing treatment plant for fly ash from incinerators. The treated industrial waste from these recycling plants is fed to Mitsubishi Process to recover the valuable materials and hazardous heavy metals.
Sumitomo Toyo Smelter and Refinery commenced its operation in 1971 with the “To Be a Pollution-Free and World’s Cleanest Copper Smelter Forever” motto. From early 1990’s to 2003, Toyo Smelter and Refinery increased its annual electrolytic copper production from 200,000 tonnes to 270,000 tonnes with the continuous technological improvements and no addition of any excess facilities. From the turn of the century, the forecast that the world copper demand would increase steady but surely especially in Asia has been rushing the other smelters into the reinforcements of their facilities and the foundations of the new plants. It is clear that this situation will lead to the age of the jungle law in the next depression. Then Sumitomo Metal Mining Co.,Ltd. has decided to increase its Toyo Smelter and Refinery’s annual production capacity to 450,000 tonnes in order to meet the demand growth and to ensure its survival by minimizing its production cost. Toyo Smelter and Refinery has finished its expansion works and would start the 450,000 tonnes production from the end of 2007.
In 1996 Saganoseki Smelter & Refinery integrated its two flash furnaces to one in order to reduce the operating cost and maintain the global competitiveness. And then many improvements were carried out to expand the smelting capacity. However, the copper content in concentrates had been decreased and also the anode production was limited. Therefore, the next project, which is called SPI (Saganoseki Process Innovation) project, was needed and started in 2003. In this project not only the smelting section but whole series of the process were modified and the productivity had been improved remarkably. The activity of SPI project and operational changes of Saganoseki Smelter & Refinery in the last decade are introduced in this paper.
Kosaka Smelting and Refining Co., Ltd. operates lead smelting to produce electrolytic lead and to recover precious metals and bismuth with mainly secondary materials from copper smelter and zinc refinery. The lead-bearing residue from zinc refinery is filtered and is dried with the leached residue from copper smelting flue dust. Then these are fed to an electric furnace with some reductant and other lead secondaries to produce lead bullion. The electro-refining of lead is based on Betts process. And we produce crude silver and bismuth metal from anode slime. According to a change of raw materials for the zinc refinery, the residue from that plant changed to high impurity contents. This raw material change becomes a very big problem for the lead smelting in Kosaka and we are doing various improvement. It is very important for lead smelting not to play rolls as the attached process of copper smelter, the zinc refinery and as the production plant of variable metal. Therefore, we are going to introduce a new technology to recover the some metals that we recognized as impurities. The recent lead operation and some experiments for lead smelting in Kosaka are described in this paper.
The Chigirishima Smelter of Toho Zinc Co., Ltd. is located on Chigirishima island of Hiroshima Prefecture. The smelter is a custom lead smelter and its operation was started in 1951. At present, the smelter produces 8,000 tons per month of electrolytic lead. This paper describes significant improvements and achieved results in by-products production process.
In 2003, the lead smelting unit of Takehara Refinery transformed to accept a new mission. This mission uses a blast furnace that has been in operation since the 1970's, and a locally developed process. Formerly, recyclable materials such as used batteries and lead residue had been treated to produce crude lead. In the middle of 2003, we changed the mission to one of charging precious materials such as used PC electric circuits and lead residue from the copper refining process to produce crude lead, gold, and silver. Accordingly, our process uses newly developed equipment to dissolve dioxins in exhaust gas. As a result of implementing the new process, the gold amount contained in the crude lead increased 185% in comparison with the previous process. This paper describes these recent operations at the lead smelting unit of Takehara Refinery.
In 1972 Akita Zinc Co., Ltd. commenced operations with the annual capacity of 78,000 ton of electrolytic zinc, and it had operated with its annual capacity of 156,000 t-Zn since 1974. The business surroundings for zinc production has been coming severer with some economical reasons. Then we tried to survive with some improvements, and succeeded to reduce the operating cost and to get more profits as follows; 1) expansion of its producing capacity to 200,000 t-Zn annually, 2) saving man-power by introduction of fully-automated machines for cathode handling at cell house operation, 3) improvement of Hematite process by means of recovery of rare-metals and arsenic removal. These measures improved profitability of Akita Zinc. But the market for zinc raw material is changing drastically and we have to treat more secondary materials by environmental reasons.
Annaka Refinery of Toho Zinc Company Limited, located 100km to northwest of Tokyo, has the annual production capacity of about 140,000tons of electrolytic zinc. On the other hand Onahama Refinery, located 200km to northeast of Tokyo, has the fluosolid roaster which treats 500ton per day of zinc concentrate and produces 570tons of sulfuric acid. Onahama plant provides about 150,0000tons zinc calcine per year for Annaka plant. This paper describes significant improvements and achieved results at the both Refineries during the last decade.
Kamioka Mining and Smelting Co., Ltd. became independent of Mitsui Mining and Smelting Co., Ltd. in 1986. Kamioka’s metallurgical operation consists of zinc electrolytic winning, lead smelting and lead electrolytic refining. The company’s main products are electrolytic zinc, electrolytic lead, zinc alloy, silver, cadmium, bismuth and sulfuric acid. Our metallurgical operation developed together with the mining operation at Kamioka mine, but the raw materials at zinc plant and lead plant were changed due to the reducing of the mine products. The new technologies that we developed to change the raw materials and the power that is supplied from the hydropower plants are our advantages. We will make effort to survive in Japan with these advantages.
Hikoshima Smelting Co., Ltd. is located at the western end of Honsyu. The plant switched from a horizontal retort process to an electrolytic zinc process in 1970. Hikoshima Co., Ltd. had made various improvements to reduce the operating costs about roasting, leaching, purification, electrolysis, casting, labor-saving and so on. In addition, the annual capacity extended from 55,000 tons to 74,000 tons during several expansion stages. Main products are zinc alloys for hot galvanizing and zinc anodes for plating. This paper describes these recent improvements and operations.
Hachinohe Smelting Company Limited operates the largest Imperial Smelting Furnace (ISF) in the world, producing 112,000 t/y of zinc and 45,000 t/y of lead. The slag fuming plant has been operating in the smelter since 1993 for the recovery of zinc and lead from the ISF slag. In November 2001 the second slag fumer was commissioned in series with the existing fumer to improve the quality of slag for use in cement manufacture and to increase zinc and lead recovery in the fume. Along with the increase of zinc production, the on-site power generating capacity was uprated from 7.5MW to 9.6MW in April 2001. As much as 70% of the total power requirement is supplied by the own power plant. In recent years, up to 40% of the feed materials have comprised secondary zinc materials.
Harima Smelter was established in July 1964 and its operation was commenced in May 1966 with a production capacity of 3,000 t/M of Zn and 1,500 t/M of Pb introducing the Imperial Smelting Process (ISP). The plant consists of sinter machine, IS furnace, zinc casting machine, lead refinery, cadmium refinery, sulfuric acid plant and indium recovery. The production capacity has been increased by various improvements and developments. In 1996 IS furnace was renewed and enlarged. In 1998 the condenser of IS furnace was renewed. In 2001 the oxygen enrichment of sinter operation was started. In 2004 the commutator of Pb electrolytic-refining was renewed and enlarged. The current production capacity is 8,500 t/M of Zn and 2,800 t/M of Pb. In 2006 the plant of indium recovery from raw materials and scraps was newly-built, and its production capacity is 6 t/M. The recent lead operation and some experiments for lead smelting in Kosaka are described in this paper.
In the precious metals processing line, raw slimes including metals and silver are first decopperized and deselenized, and then converted to noble lead in the melting and settling furnace. Thereafter, it is turned into a crude silver anode by cupellation with the residual lead from the lead refining process. This crude silver is refined by electrolysis to produce electrolytic silver. Electrolytic gold is produced from the crude gold obtained from the sediments of silver electrolysis and part of it is used to produce high purity gold for electronic industry. Aside from these metals, selenium, tellurium, platinum and palladium are recovered. Recently, We have some improvement in these processes.
Mitsui Kushikino Mining Co., Ltd. has the long history and is the only refinery in Japan which is capable of all slime cyanidation process for gold and silver ore. The Kushikino smelting plant started operation for precious metal recycling in 1978. Nowadays the recycle business has grown and the plant, so called “Hybrid smelting plant”, is Smelting precious metals from gold-silver ore and recycling materials.
Sumitomo Metal Mining Co., Ltd. (SMM) is the only one producer of electrolytic nickel and cobalt in Japan. The nickel and cobalt business of SMM, started in 1939, is the history of technological innovation and development. As the major projects developed in the past, SMM underwent a conversion to nickel matte electro-refining process in 1970, a establishment of cobalt refining process with an introduction of Mixed Sulfide raw material in 1975, a conversion to Matte Chlorine Leach Electro-winning process (MCLE) in 1992, and 1nnovations of Cobalt Electro-winning and Nickel Chemical process technology in 1999. Throughout these technological developments, in 1998, SMM has accomplished to increase the production capacity of electrolytic nickel up to 3,000t/M. Furthermore, in 2004, SMM constructed a High Pressure Acid Leach (HPAL) plant in Parawan Island, Philippine, where all the SMM's refining technology was integrated. To treat the Nickel/Cobalt Mixed Sulfide (MS) produced at the HPAL plant, SMM has improved the MCLE process at Niihama Nickel Refinery. Today, applying MCLE and HPAL technology, SMM treats the oxide Laterite Ore and constantly produces electrolytic nickel with very high quality.
Inco TNC Limited is a subsidiary of CVRD Inco, the world’s leading producer of nickel, holding the biggest nickel refining capacity in Japan located at coastal area in Mie prefecture. It has been supplying charge nickel to all of the stainless steel mills in Japan as well as its fellow subsidiary companies in Asia area since 1967. The raw material which is called nickel matte came from Canada at first. Now it processes nickel matte produced by another fellow subsidiary in Indonesia. The main processing facilities are as follows; fluid bed roasting furnace (2 lines), fluid bed reduction furnace (3 lines), briquette machine and compacting machine (1 line each). There are two sulfuric acid plants to treat SO2 gas from the nickel process facilities. Currently it is producing nickel at full capacity, 60,000 tonne / year that is 13 times of the original plan. Customer satisfaction, safety, and environment are always our most important values in the history of expansion.
HYUGA SMELTING CO., LTD. (HYUGA) was established in 1956 by SUMITOMO METAL MINING CO., LTD. ELKEM process which consists of rotary kiln and electric furnace was introduced to smelt nickel ores from Indonesia and French New Caledonia and to produce ferronickel mainly used for stainless steel. For the last decade, as for the improvement of rotary kilns, HYUGA has upgraded the off-gas fans and introduced the scoop feeders for coal charge addition. As the result, the high temperature zones of kilns have been expanded toward kilns’ charge end side and the feed rates of kilns have drastically increased. As for the improvement of electric furnaces, HYUGA renewed one of two electric furnaces in 1995 and the other in 2006. At these renewals, each transformer was upgraded and copper-cooling system was introduced into one electric furnace in 2006. Since then, HYUGA has implemented low current, high voltage electric furnace operation. This system improves the response to a wide range of ore chemistry, and it enables safe, high-load stable operation with high productivity matched to the energy situation.
Our company was established in 1934 as Oheyama Nickel Mining Industry Co., Ltd. to purpose to smelt nickel ore yielded from Mt. Oheyama, a famous mountain located in the north of Kyoto. In 1942, a nickel smelting plant by Krupp-renn process was built in this place. Krupp-renn process is one of the direct steel manufacturing process, which was developed in 1931 by German engineers to treat high silicate and low-grade ore effectively. Oheyama process is the only process in the world that uses Krupp-renn process except steel manufacturing. At the end of the War in 1945, this nickel smelting was suspended. In 1952, the Oheyama plant resume its operation with change of raw materials, from low grade ore to more concentrated nickel ore imported from New Caledonia. YAKIN Oheyama is now producing 1,000t of Ni as ferro-nickel a month.
Toho Titanium has been producing titanium metal since 1954. The present production capacity of sponge titanium is about 14,000 tons per year. In order to increase the capacity, the productivity of the process has been improved in the chlorination of ores, reduction of TiCl4, and electorolysis of MgCl2. Also, the quality of sponge titanium has been remarkably improved since 1980. For example, the concentration of nitrogen, which is an undesirable impurity, has been reduced to approximately one fifth for 26 years. Then, the production capacity of titanium ingot is 9,000 tons per year, which is being planned to increase to 19,000 tons per year in 2008. As an advanced melting, electron-beam remelting furnaces have been introduced for commercial markets. The furnaces can efficiently recycle various shapes of titanium scrap.
OSAKA Titanium technologies Co., Ltd. recently increased its annual production capacity for titanium sponge by 6,000 tons, from 18,000 to 24,000 tons per annum. Behind this expansion is robust demand from the aircraft industry, where about half of our titanium sponge product is utilized, combined with steady requirements on the part of the electric power and chemical industries, the other major users of our product. This report provides a general overview of our titanium manufacturing system by the Kroll method and the corresponding expansion of production capacity that was recently implemented. It also describes quality improvement measures that have been taken in regard to high-purity titanium for semiconductor use. At present, titanium sponge is in short supply and each and every supplier worldwide is attempting to cope with the situation by increasing capacity. As a swift response to this global trend, OSAKA Titanium technologies Co., Ltd. has proactively worked to resolve this capacity issue and, at the same time, is prepared to further improve our product quality and cost competitiveness, the most likely arenas of competition once the imbalance in supply and demand is eliminated.
Yokkaichi plant of Mitsubishi Materials Corporation was established in 1968. The products are high purity polycrystalline silicon (polysilicon) for use in semiconductors. The productivity expanded from 1.5t/M up to 1800t/Y in 40 years. Hydrogen reduction of trichlorosilane on heated silicon rod, commonly called "Siemens' process", had progressed at Yokkaichi plant. The outline of the process is described.
Japan New Metals (JNM) was established in 1963, as a joint venture between Mitsubishi Materials and Awamura Mining, and has consistently produced tungsten, tungsten carbide and molybdenum powder from raw materials. Based on the nonferrous manufacturing technologies, we have produced high purity tungsten powder, heteropolyacids and several non-oxide ceramics powders. These are used for electronics devises, hard components and chemicals. In order to avoid the risk related to the supply of tungsten raw materials greatly dependent on China, JNM started a recycling business since 2002. Tungsten is recovered from cemented carbide scraps by the chemical process in the Akita plant.
This plant was established in March, 1972. Tantalum capacitor, which constitutes an indispensable element of electronic circuits for high-reliability equipment, has been finding wider application in recent years. Cabot supermetals has been receiving favors from market as technical leading company in this industry. In this paper, details of tantalum powder production and items to be solved for future development are discussed.
Nihon Seiko was established in 1935, and at that time smelting facilities were constructed to refine ores. Sales of antimony trioxide have started since 1948. Due to exhaustion of ore reserves, mining activity was stopped in 1967. However, we continued production with imported antimony concentrates, and in 1996 raw material was changed to ingots from concentrates. Up to now, production of antimony trioxide from ingots is carried out by the continuously improved method. With increasing demands for antimony trioxide, Nihon Seiko has been developing high quality products to meet our customers’ requirements. Currently 15 furnaces, which produce antimony trioxide and metal, are in operation. Production volume of antimony trioxide is about 5,000 tons per year with a domestic market share exceeding 70%.
The Hosokura Metal and Mining Co., Ltd. produces electrolytic lead (99.99% purity) and bismuth, antimony trioxide, crude silver etc. from recycled lead-acid batteries and various types of lead-bearing industrial intermediates. Mining and smelting of lead, zinc and silver bearing ores from the original Hosokura Mine began over 1,200 years ago, but was terminated with the closure of the mine in 1987 and, since then, the production of recycled lead and the treatment of mine wastewater have been continued. The current company was reorganized in March, 2006. Although the capacity for monthly lead production based on a blast-furnace operation followed by electro-refining is around 2,000 t /month, a serious shortage of recycled batteries triggered technology development to accept lead dross and lead residue etc.also as low grade raw material in the summer of 2005. Another main operation of this company is the treatment of mine wastewater, 15 t /min on average, from the closed mine and the effluents from lead plants to meet the water quality standard against toxic elements including lead. Overcoming the lead-leakage problem at this plant in May, 2002, the thoroughly renewed and strengthened water-treating system with a big deep bed filtration facility at the final stage enables us to contribute to the environment improvement of this area and rebuild the tight, friendly correlation with the surroundings. Both the plants are operating under the company policies of environmental conservation, compliance and community involvement.
Sotetsu Metal Co., Ltd. was established in 1974 and started operation of Waelz kiln plant for treatment of EAF dust. In 1996, Sotetsu plant installed two Waelz kilns in series. At present, Sotetsu plant treats 70,000 tons of dust and produces 24,000 tons of crude zinc oxide and then 18,000 tons of high grade zinc oxide per annum. The chemical composition of the high grade zinc oxide is 78wt%Zn, 1.1wt%Fe, 0.02wt%Pd, < 0.01wt%Cl and < 0.01wt% F, and it can be used as a raw material of zinc electrowinning.
Sumitomo Metal Mining Shisaka Works has been producing zinc and lead oxide calcine from electric furnace dust of steel making process, which is called EAF dust, by using the Waelz kiln method. Since its commencement of operation in 1977, production capacity and product quality have been improved with many developments in process technologies. Recently, some technologies, especially for minimizing chlorine content of by-product called “clinker”, have been investigated in order to meet the needs of steel mills which desire to recycle the clinker as a raw material from the zero emission point of view. Based on the information obtained through the test, several improvements have been carried out and achieved the expected results. Now, Sumitomo Metal Mining Shisaka Works is pushing forward with environmental preservation so as to contribute to the development of resources circulating society.
MF is a half shaft blast furnace which has been developed at Mitsui Miike Smelter in the 1960’s to treat vertical retort residue. The MF has also been tested for treatment of various recycling materials and wastes. Now various secondaries and wastes (EAF dust, fly ash, zinc leaching residue, Cu sludge, etc.) are mainly treated. Powder materials are briquetted with reductant before being fed to the furnace. Products are crude zinc oxide, matte, non-hazardous slag and steam. Zinc and lead are recovered in oxide dust, and copper and silver are recovered in matte. The MF can be widely applied to many kinds of materials which contain such non-ferrous metal-valuables. In addition, the improvement in operation and technology has effectively made the unit capacity much larger by enrichment oxygen of air. The MF now has many advantages for treating these kinds of wastes.
The recycling of platinum group metals, especially those used for automobile and other catalysts, is widely recognized as essential, because of their limited existence in the earth's crust and high prices. To cope with such social necessity, Dowa Mining Co. and Tanaka Kikinzoku Kogyo developed a low-cost and high-recovery process, and then Nippon PGM Co., was established by these sponsoring companies. Nippon PGM Co. has been operating since then. Our processes and the recent operation in Nippon PGM are described in this paper.
Tanaka Kikinzoku Kogyo K. K. is refining and recovering the precious metals (Au, Ag, and six platinum group metal elements) and manufacturing their products. In this report, typical recycling processes for the precious metals from used electronic device, plating and deposition jigs, and the scrap containing platinum group metals such as automobile catalysts are described. These processes consist of the accurate evaluation, acid or cyanate dissolution, separation by precipitation, cementation, solvent extraction, or ion exchange, and recovery by electrowinning or chemical reduction.
Tokyo Refinery of Chugai Mining Co., Ltd. located in Keihinjima, Oota-ku, Tokyo, started its operation in August 2005. We operates a solvent extraction process for gold recovery refining. Solvent extraction can provide significant reductions in operational costs. High grade secondary metallic sources with a high precious metal content, such as jewelry scrap, are first brought into solution with aqua regia. Silver forms insoluble AgCl which is separated and recovered by filtration. Gold is extracted by the solvent extraction schemes into the organic phase, and scrubbed with hydrochloric acid for impurity removal. Gold is reduced and recovered from the organic phase with reducing agent. The capacity of gold refining process is 520kg per month. The all manufacturing processes take only three days.
Since the amount of natural resources is decreasing year by year, the recycling of precious metals from waste materials, coming from industrial plants, hospitals, or private consumers, should be carried out in order to save resources and protect the environment. Nevertheless, the structure of such waste materials is becoming complicated year by year. In turn, new processing technologies should be developed to treat such waste materials for recovering valuable products. Within this frame, the aim of this paper is to introduce the current status on how the recovery of various metals from waste materials is being carried out at Yokohama Metal Co., Ltd., the company specialized on recycling of precious metals.
Nomurakohsan Co., Ltd. has been treating the wastes containing mercury for over 30years at Itomuka Plant located in the mountains, north-east of Hokkaido. Its treating materials are used zinc-carbon and alkaline-manganese batteries, used fluorescent lamps, mercury-containing wastes, medical wastes, used chemical reagents and so on. This paper introduces the current situation of Itomuka Plant, especially the treatment of zinc-carbon and alkaline-manganese batteries, used fluorescent lamps and mercury-containing wastes.
The Ikuno tin smelter has started its operation in 1913, followed by tin refinery in 1916. Originally, the reverberatory furnace had been used for smelting, but later it was replaced by the present electric furnace in order to improve productivity and increase tin recovery. The refinery was relocated from Ikuno to Osaka in 1920, and then again relocated to Naoshima in 1960.The present refinery in Ikuno has started operation in 1991. After Akenobe mine was closed in 1987 due to low tin price and its poor mining condition, domestic secondary materials from the market has been purchased and treated. At present, Ikuno plant is the only producer of electro-refining tin in Japan and 65t/month of electric-tin has been produced.
Daiki Aluminium Industry Co., Ltd. (DIK) is a leading aluminum recycling company in its secondary aluminum alloy ground metal production. Since the foundation in 1922, DIK, as a pioneer in the aluminum alloy industry, has been offering the products which the market requests. In fiscal year ended March 2007, the capital of the company is 6,346 million yen, the number of employees is 344, and the production volume is 296,849 t / year. We have five production plants (the Kameyama plant, the Shiga plant, the Shinshiro plant, the Yuki plant, and the Shirakawa plant). This report shows DIK’s production facilities and technical features, the pretreatment of materials and the recycling of the materials produced during processing, and our future challenges.
DOWA group has been working on metal recycling applying the smelting and refining process of KOSAKA Smelter. DOWA has developed it's metal recycling technologies through the treatment of complex sulfide ores that contain many kinds of non-ferrous metals. In addition to these special technologies, DOWA has strengthened its hydrometallurgical process of precious metals and ability to deal with low-grade materials such as used electrical appliances or vehicles. In Akita Eco town area, DOWA recovers as many as 16 kinds of metals from various recycle materials such as circuit board scraps, catalysts, ASR (Automobile Shredder Residue) etc. Furthermore, DOWA group has started the construction of a new furnace in order to efficiently recover more metals. Recently, DOWA is expanding the business field to China and South East Asia for establishing a new recycling network in Asia and for the realization of a recycle-oriented society.
Nippon Mining & Metals company (NMM) carries out its metal recycling and industrial waste treatment businesses employing advanced separation, extraction and refining technologies developed through its extensive experience in the smelting of non-ferrous metals. It collects approximately 100,000 t/y of copper and precious metal scraps from waste sources such as electronic parts, mobile phones, catalytic converters, print circuit boards and gold plated parts. These items are recycled through the smelting and refining operations of Saganoseki smelter and Hitachi plant of the NMM affiliate NIKKO Smelting Company. In addition, environmental services are provided through four other affiliates: Nikko Environmental Service, Tomakomai Chemical, Nikko Mikkaichi Recycle and Nikko Tsuruga Recycle. The purpose of this paper is to provide an introduction to the recycling and environmental service operations of Nippon Mining and Metals group.
Desulfurization catalyst containing molybdenum is used in oil refining to remove the sulfur. This desulfurization catalyst loses its activity by adhesion of nickel and vanadium present in crude oil, and is exhausted as waste catalyst. We have been recovering the molybdenum and vanadium from the spent catalyst since 1978. The recovered molybdenum is recycled again for the catalyst as pure MoO3. Moreover, the obtained vanadium (V2O5) is reused as ferro-vanadium alloy by the thermit process. By our recycling system, high quality molybdenum and vanadium are efficiently provided. Thus, we are producing vanadium of purity 99.9% from the recovered vanadium.
KOWA SEIKO Co., Ltd., engages in establishing a sound material-cycle society through waste treatment, recovers valuable metals such as Cu, Pb, Zn, etc. and produces raw materials such as pellets for iron blast furnace and iron oxide for cement making from various industrial wastes by chloridizing volatilization process which is our original technology. We have built a recycling system designed to achieve zero emissions and are still expanding the range of services as shown by the initiation of the recycling of molten fly ash in 2006.
Decomposition of recovered chlorofluorocarbons (CFC) and hydrochlorofluorocarbons (HCFC) has been carried out in our industrial waste incinerator since 1997. We set up the facilities to recover 1,000 t/y of CaF2 (fluorspar) from the drainage with high fluorine content which is generated in a flue gas scrubber attached to the decomposition process of CFCs/HCFC. These facilities have been operated since 2004, and the quantity of the recovered CaF2 amounted to 400 t in 2006. The recovered CaF2 has been used as resources for steel makers and chemical makers. Several problems of cost and impurities of the recovered CaF2 remain to be solved in future. This report describes the operations of the recovering facilities and several problems on recycling.
In Japan, the domestic recycling system of the nonferrous metal is formed with two businesses. One is many collecting & sorting enterprises and processing & wholesale enterprises, which are usually small and medium-sized business. The other is nonferrous metal smelting & refining enterprises, which are usually big business. Recently legislative resource recycling system, which consists of Home Appliance Recycling Law, End-of-Life Vehicles Recycling Law, Law for Promotion of Effective Utilization of Resource and so on, has been also developed. But, in spite even in these circumstances, considerable amount of domestic occurrence scraps of copper has been exported to China, and a lot of used home appliances and used personal computers have been exported to foreign countries. Namely, it has become clear that the present resource recycling system could not circulate the resources sufficiently inside Japan. These problems were caused by rapidly increasing resource consumption of the world in these several years, which was originated by quick economic development of the Asian region, in especial in China. Tightness of worldwide resource demand has requested the advancement of creating new countermeasures and/or corresponding methods under the slogan of “conservation and effective utilization of resources” for a long time. This manuscript intoroduces these circumstances and suggested some solutions to the problems.