World of Metallurgy ERZMETALL 68 2015 No 3 179 Takashi Yoshida The Advance of Zinc Industry in Japan The History and the Future from the Point of View Japan on the basis of usage Consumption increased steadily from the 1960s to the first half of the 1990s Almost 70 of zinc in Japan is used for galvanizing especially in continuous galvanizing lines Galvanized steel plates are mainly used in automobiles Increases in automobile production induced increases in zinc production and its usage until the first half of the 1990s In particular demands for improvements in corro sion resistance for automobile plates through the Canadian code Norwegian code and other processes were made in the 1970s and zinc production increased to meet these demands 7 Automobile manufacturers later began moving overseas and galvanized steel sheet production decreased lowering zinc consumption The use of die cast zinc which was often used in the past also decreased significantly as automobile downsizing created the need for plastic alternatives In view of these trends the use of zinc in Japan is likely to continue to decrease in the future However production that meets the domestic demand must continue The Harima Smelter announced that it will cease zinc production in 2015 so sup ply will decrease but production adjustments and structural changes will be needed even more in the future 6 2 Security of raw material Japan depends on imports for nearly all of its zinc concen trate the principal zinc raw material Japanese corporations have invested in some mines but the proportion of mines owned and operated by these corporations is low Large scale mines have shut down and securing zinc concentrate has become more difficult In addition with increasingly complex mineralization of the ores impurities have in creased grain refining has progressed and there is a high probability that operational problems within roaster and problems caused by impurities may occur Furthermore purchasing condition of concentrate has become more difficult Many of these problems lie in the dependency on sulfide concentrate so the need exists to recycle zinc con taining waste materials such as EAF dust and treat zinc with recycled materials Furthermore efforts should be made to use completely new types of raw materials such as hydrothermal ores from the ocean 6 3 Management of harmful impurities An issue that cannot be avoided is the proper disposal method or suitable treatment of impurities Some key factors include international conventions on regulating mercury and the presence of arsenic in future Japanese zinc smelting operations Methods of storing arsenic as a stable compound have been proposed which will serve as examples in the consideration of future approaches to manage impurities The Japanese zinc smelting industry has superior antipollution technology and technical prowess to separate and collect harmful metals but questions persist as to how reuse these harmful metals as well as how to safely dispose or store them 6 4 Energy problems As previously mentioned there have been changes in en ergy prices in recent years energy prices in the future will be an important factor for the zinc smelting industry The price of coke which is used in the ISP and the price of elec tricity which is used in the hydrometallurgical process will have significant effects on business profitability The electric power issue is especially important in Japan because all of the country s nuclear power plants were shut down in wake of the Fukushima Nuclear Power Plant accident caused by the Great East Japan Earthquake of 2011 The electric pow er supply system has changed a great deal and it remains unclear whether the nuclear plants will restart operations As a result the rising cost of electricity will likely have a substantial effect on hydrometallurgical zinc processing Aluminum smelting has almost completely disappeared in Japan and the same thing could happen to zinc 6 5 Technological developments required for the future For zinc smelting to continue in Japan technological de velopments are strongly required to keep worldwide com petitiveness The technological development of treatment method for dirty and complex raw materials is necessary To reduce smelting cost the energy saving is most impor tant both pyro and hydrometallurgical process New anode material which reduces oxygen over potential is highly required for electrolytic process To develop cheap coke al ternative will be contributes for ISP New method for treat ing and stable stock of harmful element is important for the future Technology of increasing the added value of zinc is also important Technology to overcome future regulatory issues is essential Thus so many technical requirements are still key issue for future zinc industry 6 6 Paths forward for the Japanese zinc smelting industry The zinc smelting industry in Japan is experiencing many challenges The important function of non ferrous metals such as copper lead and zinc smelter is to recover rare metals included various raw materials Also many kinds of industrial waste such as waste plastics e waste ASR waste batteries various scraps waste electric appliances spent glasses and others are treated These functions are very important for human society Also each non ferrous metal smelter cop per zinc and lead smelters are supported each other Zinc and cadmium bearing residue produced by copper smelter should be treated by zinc smelter and copper bearing resi due from zinc smelter should be treated by copper smelter Thus zinc smelter in Japan should exist to contribute funda mental society not only for zinc producer but a member of constitution for total society Our mission of zinc smelter is to continue these operations no matter how difficult things develop into Having said this however it is onerous for just one private company to take on this responsibility alone industry research and educational institutions such as uni versities and the government must all work together to make this happen 7 Summary We have discussed past changes in the business environ

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