PT Smelting is a joint venture company (Mitsubishi Materials; 60.5, Freeport Indonesia; 25, Mitsubishi Corp. 9.5 and Nippon Mining and Metals 5%) established on 7 February 1996 to construct and operate a copper smelter and refinery in Indonesia. The construction work started in 1996 and completed in August 1998 after two years construction period. Test operation started in December 1998 and commercial delivery of cathode copper commenced in May 1999. Designed capacity of the plant is 200,000 tons of cathode copper from concentrate supplied from Grasberg copper mine in Papua of PT. Freeport Indonesia. The Mitsubishi process is applied to the smelter and ISA process is introduced to the refinery.
In 1999 the operation was 66% of designed capacity, 95% in 2000 and in 2001 the cathode production exceeded the design figure by 7%. About 25% of cathode copper is delivered to domestic customers and the rest to south east Asian countries such as Thailand, Malaysia, Taiwan, Singapore and Vietnam. All the sulfuric acid is sold to the next- door fertilizer plant and all the slag is delivered to the domestic cement industry.
Japanese assistant team for starting-up stayed 5 months. After they left from Gresik, all the operations and maintenance work have been performed 100 % by Indonesian operators with small number of Japanese supervisory engineers.
The sulfur fixation rate is over 99.7% and the effluent meets the stringent Indonesian standards. Clean operation of the Gresik smelter and refinery has attained by a full support from surrounding communities.

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For increasing demand of titanium-based materials, and for making contribution to the development of Japanese material industry, it is essential to reduce production cost of titanium by developing new reduction process of titanium, which can replace the current Kroll process. When reviewing the past research works, there are many original studies and technologies developed. However, most of these technologies are not sufficient for practical development of the new process. The combination of some of these key technologies is expected to induce germination of the new process. After designing the target new process by assorting and arranging the past research findings, general program for development of the new process has to be initiated.

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Energy resources are required for human beings to establish the sustainable society. The information of sub-surface structure is essential to extract the resources from underground.
At first in the present paper, the technical trends of geophysical exploration to grasp the underground structure and its physical property are described with emphasis on the necessity of the 3-dimensional survey and the presentation and the integrated interpretation of geophysical data by use of virtual reality information technology.
Then, the technical extensions for exploration and exploitation of conventional and new energy resources concerning with petroleum and natural gas, coal, mineral, geo-thermal, oil sand, methane hydrate, micro-gas turbine and wind power generation in Japan are introduced.

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The acoustic emission (AE) method under a confining pressure has been developed in order to measure in-situ stress that is expected to be close to the uniaxial compressive strength or to estimate the stress from weak rock, which are very difficult to deploy the conventional AE method based on standard uniaxial loading. We have developed a special small pressure vessel by which AE event can be detected under a confining pressure. We tested the ability of the vessel to detect the Kaiser effect of AE occurrence under a confining pressure. Then, we evaluated the AE method under a confining pressure by conducting a simulation test of determination of pre-stress using a soft sedimentary rock from Tono mine in Japan. The result showed that the previous stress could be estimated under a confining pressure with reasonable accuracy of 3.3 % mean error.

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Pure aragonite was synthesized from calcined scallop shells in a single step in the presence of Mg²⁺ ions at ambient temperatures under the controled CO₂ flow rates. The Mg²⁺ ions seem to behave like a catalyst to form aragonite, since most of the Mg²⁺ ions remained in the solution. However, very small amounts of Mg²⁺ ions was selectively adsorbed onto the surface of fine calcite crystals to inhibit further growth of calcite. The morphologies and sizes of aragonite was strictly controlled by the reaction temperature. It was a characteristic property of calcined scallop shells to produce the aggregated aragonite. This study possibly would contribute to a better utilization of waste scallop shells and to establish a "soft process" for producing fine particles of aragonite.

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Electrokinetic soil remediation is an effective in-situ separation and removal technique used for extraction of heavy metals and some organic compounds from fine-grained soils. The technology uses electricity to affect chemical concentrations and water flow through the pores of soils. It is clear that electrokinetic soil remediation by electroosmosis and ionic migration is restricted to soluble substances. Contaminants that are adsorbed on the soil or are present as precipitates can not be effectively removed. In particular, the solubility of most heavy metals may be significantly reduced at elevated pH values. When impurities such as iron oxides are present, electrokinetics alone may not be effective in the extraction of heavy metals due to the higher acid/base buffer capacity. Also, acidification of the medium might cause large weight losses by dissolution of part of the solid matrix. It would therefore be better if the treatment were performed at neutral pH.
In the present study, the effectiveness of introducing a complexing agent to enhance the removal of cadmium from kaolinite in the region of neutral pH by ionic migration is examined. The complexing agent selected was ethylenediaminetetraacetic acid (EDTA). The investigation was carried out in a laboratory-scale column containing kaolinite contaminated with cadmium. As the results of the study, cadmium migrates toward the anode without accumulation of cadmium and is successfully removed at the anode reservoir.

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Several modifications of lead anode for zinc electrowinning have been studied. The results are summarized as follows;
(1) By using a Pb-Ag-Ca alloy anode, the bath voltage decreased compared with the conventional Pb-1%Ag anode, and the anode potential decreased with increasing in the content of Ca and Ag in Pb-Ag-Ca anodes.
(2) At the beginning of the electrolysis, the amount of the generated gas on the Pb-0.5%Ag-0.6%Ca anodes was larger than that on Pb-1%Ag anodes and the increase in Ca content in the Pb-Ag-Ca anodes caused a larger gas.
(3) The original microstructural features before electrolysis were investigated with the EPMA. In the Pb-0.9%Ag alloy, the fine particles of Ag-rich phase was found to be homogeneously distributed around the Pb grains. In case of the Pb-0.5%Ag-0.6%Ca alloy, the Ag-rich phase was scattered in the grain boundaries.
The content of Ag in the Ag-rich phase of the Pb-0.5%Ag-0.6%Ca alloy was higher than that in the Pb-1%Ag alloy.
In the Pb-0.8%Ca and Pb-0.5%Ag-0.6%Ca alloy, the CaPb3 phase appeared.

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Long lasting red-emitting phosphorescence properties of Eu³⁺ in YVO₄ compound were investigated. YVO₄: Eu³⁺ shows a red-emitting phosphorescence due to the ⁵D₀ → ⁷F₂ transition of Eu³⁺. Effects of the firing conditions and Eu₂O₃ content on the phosphorescent properties of YVO₄: Eu³⁺ samples were discussed in terms of crystallite size of the compound. The phosphorescence intensity and lifetime of YVO₄: Eu³⁺ increased with increasing the crystallite size of compound. The optimum conditions to fabricate YVO₄: Eu³⁺ were determined in terms of phosphorescence lifetime; consequently, firing temperature, time, and atmosphere and Eu₂O₃ content were 1,100 °C, 3 h, air, and 12.5 mol%, respectively. The phosphorescent lifetime of YVO₄: Eu³⁺ fired under the optimum conditions is approximately 10 min.

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