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.
Susumu KOSEMURA, Shigeo AMPO, Eiichi FUKASAWA, Yoshihiro HATTA
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.