Finite difference method is applied to simulate the thermal environmental conditions in a developing roadway with forcing auxiliary ventilation. The local heat transfer coefficients which were obtained by simulating the heat and mass transfer process in working face with CFD method are coded into the program for the prediction of the thermal environmental conditions in working face. The 3-demensional heat conduction in surrounding strata rock, the heat and mass transfer between the airflow in the duct and roadway, the heat and mass transfer between wet rock surface and roadway air are simulated with taking into consideration the air leakage of the ventilation duct and the advance of the working face. The distribution of the air temperature and relative humidity of the air both in the duct and roadway, and their variation with time can be predicted by the program when forcing auxiliary ventilation is used. The model for the prediction of the thermal environment can provide a reliable approach to predict if a climate problem exists in the design stage, allowing suitable ameliorative measures to be tested and evaluated prior to the start of driving. It will contribute to establishing the rational method for improvement of the thermal environment, by proposing more effective technological guide in the control of heat problems in working face with auxiliary ventilation.

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In this paper, new approaches for testing and interpreting ground thermal conductivities in Ground-Coupled Heat Pump (GCHP) systems were proposed. With the application of Horner plot method, developed in petroleum engineering, the new approach does not require the condition of constant heat flux during the thermal response test. The application of the new interpretation method to field test data showed reasonable agreement with conventional methods, while proposing the requirement of multi-point down-hole temperature measurements when testing heterogeneous formations. The evaluation of skin factors using the new approach showed that the temperature loss around boreholes due to the small thermal conductivity of grouting material would be of less importance than conventionally evaluated.

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An experimental study on the removal of molybdenum from industrial waste water by adsorption method was carried out. The findings of the present study were as follows:
(1) The lead compound showed the ability to adsorb Mo(VI) ion from an artificial molybdenum waste water. The maximum uptake of Mo(VI) was 0.049 kg·kg^-1 under the following conditions : solution pH = 3 ∼ 7, initial concentration of Mo(VI) ion = 50 mg·dm^-3, and agitation time = 2 h.
(2) 99 % of adsorbed molybdenum was eluted from the lead compound by adding 0.5 mol·dm^-3 NaOH.
(3) We also succeeded in removing Mo(VI) from industrial molybdenum waste water (Mo concentration = 270 mg·dm^-3, pH = 8) produced during the process of production molybdenum catalysts. The molybdenum concentration of the treated waste water decreased below the detection limit within 30 minutes of reaction time. This study confirmed the viability of our proposed method.

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To produce high-quality electrolytic copper, the influence of additives on copper electrodeposition was studied, and the design and control of the additives in copper electrorefining were discussed in the present paper. The experiment for the influence of the additives such as glue, thiourea and chloride ion in the copper electrolyte on the surface roughness in electrodeposition were carried out with the Hull Cell test and the practical scale test, and the additives strength was defined by the concentrations of these additives, which was clarified to be useful for controlling the copper electrolyte. An expression as a function of the copper concentration in the electrolyte, the additives strength, the current density and the electrode space was also derived for obtaining the smooth electrodeposition, which is of great help in controlling the copper electrolysis.

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The composite powders of Ag-NiO were prepared by spray pyrolysis from Ag and Ni loading Versatic Acid 10, which was used for the separation of metals as an extractant. The external shapes and the internal structures of the obtained composite powders were investigated by using SEM, XRD and EPMA.
The composite powders were secondary agglomerates with the particle size of several μm ∼ 10 μm and agglomerate powders were composed of some spherical particles with the size of one micron or less as observed by SEM photographs. The composite powders prepared by spray pyrolysis from the organic phase were the powders comprising Ag-NiO from the analysis of XRD. The Ag-NiO composite powders were made of the Ag layer in the internal region and the Ag-NiO composite layer in the external region from the result of the EPMA analysis. The structure of the obtained powders was different from the internal structure of the composite powders prepared by spray pyrolysis from the metal nitrate solution. The new powder production process where the separation with solvent extraction was carried out , followed by spray pyrolysis, was proposed. In this process the composite powders were prepared by spray pyrolysis from the organic phase loading and refining the targeted elements from the impure raw materials like wastes.

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Recovery and recycling of electric arc furnace (EAF) dust are not enough although containing iron and zinc as metallic resource. Conventionally the EAF dust is collected by a bag filter after being completely cooled down, and half of the dust collected is re-melted in the melting furnace such as the Wealz kiln and the other is treated by sanitary landfill. This re-melting method is quite energy- and time-consuming with environmental problems. Therefore, a new dust treatment process using a coke bed filter, proposed by JRCM (The Japan Research and Development Center for Metals), was fundamentally studied, in which various carbonaceous materials were mainly examined to determine a packed material of the filter. In the cold experiments, adsorb property of the simulated EAF dust was evaluated by using six carbonaceous materials; charcoal, graphite, EAF coke, BF coke, pitch coke and carbonized RDF (Refuse Derived Fuel). The sample was suspended under the flowing condition of particles with average diameter of 300 nanometer and its weight changes due to adsorption were monitored by a high-accuracy balance. As a result, 1) the weight increase depended strongly on a kind of samples. Interestingly, the carbonized RDF with largest BET specific area is most adsorbable and the graphite with smallest BET specific area is least. 2) The adsorption of submicron particles occurred within the sample, not on the surface. 3) a porous material having 1 to 10 μm in pore size with larger BET specific area is absolutely effective for collecting the EAF dust. In other words, the pore for collecting particles should have one-order-larger size than the particle. SEM observation of the coke used in the pilot plant also suggested the validation of the conclusion obtained.

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This article describes the present status of pressurized fluidized bed combustion (PFBC) technologies for coal. PFBC technology is commonly recognized as a future generation coal combustion technology and R&D has been done among advanced countries. PFBC technology offers a high efficiency and low emission combustion technology of coal by using a combined cycle power generation system. Wide variety of coal, lignite to anthracite, can be burned by PFBC technology, and coal energy can be converted to electricity with higher thermal efficiency. PFBC technology has recently entered the commercial stage. In Japan, three units have been under commercial operation. In other countries, some commercial units are under construction or operation. Their operability and performance are good enough to be a commercial plant. Especially, NOx, SOx and particulate emissions are acceptably low.
Thermal efficiency of PFBC technology, however, is not high enough among the advanced coal based power generation technologies, such as integrated coal gasification combined cycle power generation (IGCC), integrated coal gasification fuel cell power generation (IGFC). Net thermal efficiency of PFBC is near 40%, because inlet temperature of gas turbine is limited. On the contrary, IGCC or IGFC gives high net thermal efficiency higher than 45%. In order to increase thermal efficiency, a new type of PFBC (advanced PFBC, A-PFBC) is now being developed. A-PFBC can improve inlet temperature of gas turbine and gives higher thermal efficiency as same as that of IGCC.
Current PFBC technology seems to be not suitable for large scale commercial power generation, because of its higher construction and operational cost. It is very difficult to scale-up PFBC unit to very large scale as same as conventional pulverized coal combustion system. Other usage of PFBC may be more possible, because PFBC has high potential in the flexibility of fuel. Medium scale PFBC less than 50MWe is another choice. It can burn wide variety of fuels including wastes, and produces electricity and heat.
In order to improve PFBC technology, fundamental research works are needed. Fundamental research on combustion behaviors of wide variety of fuels, combustion rate, agglomeration are presented.

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Recent Status and Prospect of Preparatory Study of Combined Cycle Power Generation System using Hypercoal are reviewed. The concept of the system is to completely remove coal ash in a very early stage of coal utilization so that a gas turbine can directly burn coal. This preparatory study started April, 1999 for 3 years and involves developments of ; (1) Hypercoal production process to completely remove deleterious ash from raw coal; (2) Evaluation of Hypercoal as a feedstock for the existing gas turbine power generation systems and an environmental performance of different coal utilization technologies. Ash content of some Hypercoals is less than the target value, 200 ppm, and removal of alkaline metal is within the range of possibility. The results obtained during three years indicates the attainment of the preparatory study. After this study, the phase 2 of the project using large scale Hypercoal production unit will be expected to start in order to verify the concept of this system.

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Quality design is one of the important tasks for new developing coalmines in order to satisfy the market needs in Japan. However, quality control involving the practical evaluation of actual boiler properties is not carried out at coalmines. Therefore, unexpected troubles often take place during coal handling and combustion at coal users.
The purpose of this study is to establish the coal quality design and quality control system that predict the actual boiler performances and feedback their results to coal production management. This study was carried out in step with a development schedule of Xuchang coalmine in Shandong province, China. Prediction of boiler performance based on the properties of test production sample, evaluation by pilot plant test, optimization of preparation process, establishment of quality control system and verification by actual boiler test at user were described.

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It is a worldwide problem to treat the diesel exhaust gas as clean as possible because the toxic emission damages not only a human health but also the global environment. In underground mine, it is also a serious problem because the space is limited and it is probably possible for workers to be exposed from the diesel exhaust gas.
Taiheiyo Coal Mining Co., Ltd (Taiheiyo Coal Mine) introduced the three types of diesel vehicles using the exhaust gas water type treatment system in the past. However there were many troubles such as supplying the water in a scrubber tank frequently, cleaning a scrubber tank anytime and keeping a floor in good condition. To solve these kinds of troubles, Taiheiyo Coal Mine developed new exhaust gas dry type treatment system consisted of the new oxidation catalyst, modified flame arrester, spark arrester and ceramics filter. As a result of exhaust gas analysis, the low content of toxic emission and temperature level in exhaust gas that could clear the government approval standard were achieved. Especially, CO and HC content were lower than limitation of the heavy diesel vehicle on surface in 2003.
Two types of diesel vehicles, one is 75kw LHD and the other is 45kW dump truck, have developed and operated since 1997 in underground. In this paper, new exhaust gas dry type treatment system and results of the exhaust gas analysis are described. Subsequently, efficiency of diesel vehicle compared with a conventional method is discussed.

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Thermal extractions with several polar and non-polar solvents were carried out in order to produce “HyperCoal” (ashless coal) in a high yield. Effects of extraction time and temperature on the extraction yield (HyperCoal yield), and suitable parameters to select coals for HyperCoal production were investigated.
We previously reported (Yoshida et al., 2001a) that softening temperature of raw coals is an excellent index for coal giving high extraction yields with Light Cycle Oil (LCO), which is a non-polar and cost-effective solvent. However, in relation to the coal softening, the maximum fluidity did not simply correspond to the extraction yield at 360°C, suggesting that such a high extraction yield can be strongly related to the structural changes occurred at its softening temperature, where thermal relaxation of non-covalent interactions coal actively occurs.
Thermal extraction yields with non-polar solvent such as LCO were high for coals around 76 ∼ 81wt% (daf) carbon contents, and the ash content in LCO HyperCoal was 0.03%. In the case of using polar solvent, the extraction yield increased, on the other hand, the amounts of the remained solvent and mineral matters in HyperCoal became larger, compared to the case of non-polar solvent.

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The Japan Coal Energy Center (JCOAL) was engaged in the "Japan / China Joint Cooperation Project on Spontaneous Combustion Prevention Technology" of a five-year plan starting in 1996. This is part of the "Commissioned Study Project for the Promotion of Stable Coal Supply". The joint research project was initiated in collaboration with the China Coal Mining Research Institute. In the execution of the research project, the Fushun Branch, Coal Mining Research Institute assumes the role of the coordinating counterpart for the Chinese side.
The purpose of this research project is to develop a model for spontaneous combustion prevention through the development of the equipment (hardware) and technology (software) based on the practical applicability experiments in Japan. To achieve this goal, JCOAL will undertake the fabrication of the hardware such as monitoring and measuring equipment, technical instructions and guidance on a short-term basis, system design, and data analysis and evaluation. The Chinese counterpart will carry out in-situ tests to substantiate the practical applicability of the technology at a model coal mine, Lao Hu Tai Colliery, Fushun Mining Bureau, and analyze the test data.
In 1996, there have been more than 90 spontaneous combustion incidents at Lao Hu Tai Colliery. The most encouraging result of the cooperation project is the fact that they have not experienced spontaneous combustion incident in 2000.
In this paper, a general overview of the project and the typical result are described.

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