A large amount of marine organic residue is generated and wasted from scallop shell processing manufacture. Because the waste product of scallop, especially the mid-gut gland contains a large quantity of heavy metals such as cadmium and copper, it cannot be effectively used. Now, a large part of these wastes are treated in landfills. However, in recent, the landfill treatment runs into trouble because of an environmental pollution and a decrease in proposed landfill ground. Consequently, the development of a new treatment method of the scallop waste is really required. In order to recycle the organic residue of scallop mid-gut gland, a new technology has been developed for removing the harmful cadmium and using as fish meal and fertilizer.
This treatment consists of a cadmium leaching process from the mid-gut gland in a sulfuric acid solution and a cadmium electro-deposition process. This new treatment technology corresponding to hydrometallurgical process can remove more than 95% of cadmium from the mid-gut gland. At first, influences of various factors on cadmium removal efficiency such as acid concentration, electrolytic voltage, anode materials and so on, were examined to decide the most suitable conditions of an electrochemical treatment method by using a small scale plant test.
And secondarily, a demonstration plant to enable one batch treatment of about 100kg/day was designed on the basis of the results of a fundamental experiment, and a prototype plant was built. Finally, a demonstration test was conducted.
The dried and crushed wastes products of scallop after the removal of cadmium were reused as a feed and fertilizer materials, and in the year 2000, two recycle plants of the scallop waste on the basis of this development research were constructed at Oshamanbe-cho and Sawara-cho in Hokkaido, and now under operating.

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Overcoring rock stress measurement method has been used in most of projects of constructing large rock caverns for hydro-power plants and oil storage in Japan. This is because the principle of the method is clear and reliable measurement devices have been developed. Overcoring stress measurement method is applicable to both isotropic and anisotropic rocks, but only methods assuming isotropy have been actually available in engineering. Rock is sometimes very anisotropic and the importance of considering anisotropy in rock stress measurement has been pointed out by several authors. One of the major reasons for the fact that there has been no practical method taking into account the anisotropy is that it has been very difficult to determine anisotropy of the rock at the location of the overcoring.
In this paper, adopting a new method for determining orthotropic anisotropy by pressurizing a hollow cylinder, a practically applicable rock stress measurement method is developed. Then an example of applying the method to a field data is shown. Further, the error in the resultant stress state when isotropy is assumed for anisotropic rock is discussed through many simulations.

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In order to obtain fundamental data for the evaluation of permeability in methane hydrate reservoir, we have conducted experimental and analytical studies on the behavior of formation and dissociation of methane hydrate in porous media and the change in permeability in the process of formation and dissociation. The experimental apparatus for permeability measurement was originally designed and manufactured. Very uniform methane hydrate reservoir was achieved by the method of gas injection into sand column. The artificial sample of sand column with methane hydrate was satisfactory for the experiment of absolute permeability measurement. As a result of the experiment, it was found that the formation rate of methane hydrate in porous media depends on the particle size distribution of sands composing porous media. The interfacial condition between methane gas and pore water was an essential parameter of formation. In an experiment of dissociation of hydrate by the injection of hot water, the increase of permeability in methane hydrate reservoir was observed as a function of time. The large decrease in permeability was also obtained as a result of reformation due to flow of dissociated gas in porous media. The apparent absolute permeability drastically decreased as the hydrate saturation in sand column becomes lower. The values of the permeability in the case of hydrate saturation 40 % were 1/30 to 1/50 compared with the original values without any hydrate formation in porous media.

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Laboratory experiments were conducted to measure gas permeability and P-wave velocity under hydrostatic pressure in Shirahama and Tako sandstones with porosity of 12% and 24%, respectively. In dry samples, gas permeability and P-wave velocity were significantly changed with increasing hydrostatic pressure in Shirahama sandstone, as a result of the closure of micropores with low aspect ratio, while in Tako sandstone they were less affected. In water-saturated sample, velocity changes caused by CO₂ injection, are typically on the order of -6%. P-wave velocities decreased almost simultaneously along horizontal paths in two orthogonal directions. Results of P-wave velocity tomography suggested that cross-well seismic profiling is useful to monitor migrations of the injected CO₂ in geological sequestration sites.

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Coarse particles in a solid-liquid flow through a pipe settle and come into contact with each other at the bottom of the pipe. In order to simulate such flows by means of the conventional point force model, the grid size of the continuous phase must be much larger than the particle diameter. This causes low resolution of fluid velocity. In this study, a method for simulating a flow containing spherical particles 1.7-times larger than the size of the fluid grid was mentioned. A distinct element method (DEM) used for uniform particles in diameter was also improved for particles with size distribution. A comparison of results obtained by simulation with experimental observations indicated that results with acceptable levels of engineering accuracy for predicting motions of coarse particles in solid-liquid flows can be obtained by using the proposed method.

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A corresponding distribution of electric potential is produced in a porous medium like sand and an aggregation of broken rocks, if a temperature distribution exists in the medium. The authors performed model experiments to investigate whether the measurement of the electric potential distribution can be used for locating the heat source. The main parameters measured are electric potential and temperature. The results of the experiments show that a distribution of electric potential is always created corresponding to the conditions of the heat source. It is concluded that there is a possibility that the measurement of potential distribution can be used for locating the heat source of spontaneous combustion of coal.

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A mine fire generates toxic gases and influences airflow in the mine ventilation network. Therefore, the knowledge of the effect of the mine fire on the network and the gas distribution in the roadways is indispensable for the management of escape, rescue and fire fighting activities. The ventilation network analysis during a mine fire will be one of the useful tools for these purposes. Also it is expected to give significant information to perform effectively mine ventilation control during a mine fire.
The authors developed a computer program to simulate airflow changes and gas concentration in a network during a mine fire. The program introduces the "ventilation pressure created by a fire (natural draft effect)" and the "throttling effect" into the analysis. The performance of the program has been investigated, using the data of actual mine ventilation network data and of a fire experiment in the Experimental mine. The program is proved to give useful results to make effective countermeasures to mine fire and to make effective education about mine fires for the people who work in underground.

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The simultaneous hydrothermal synthesis is described on spinel-type ferrites from ferrous hydroxide with 0.34mol% Ni(OH)₂ and matrix materials in CaO-SiO₂ system. It is possible to synthesize large-size particles of ferrous hydroxide by the presence of NH₄Cl as a reactive moderator, while the presence of Ni²⁺ promotes magnetite synthesis in the simultaneous hydrothermal synthesis method. The simultaneous synthesis composite has a Fe content of 60wt% in the form of Fe₃O₄, with matching characteristics of -40dB for reflection loss and 4.0 mm thickness at 5.77GHz for the single-layer electromagnetic wave absorber. In the case of a double-layer type electromagnetic wave absorber for ETC systems, in 5.8GHz, the first layer is a calc-silicate plate of 7.3mm thickness, with the second layer being a 7.9mm thick simultaneous synthetic composite of 80wt% Fe (as Fe₃O₄). The double-layer type electromagnetic wave absorber has the same absorbing properties as the composite obtained from commercial Mn-Zn ferrite and matrix materials in CaO-SiO₂ system.
The new method for synthesis of electromagnetic wave absorber, described in this study, can be readily achieved for practical utilization, and expected to provide simple and efficient manufacturing of electromagnetic wave absorber at low cost.

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Arsenic and antimony activities in the Fe-Co-As and Fe-Co-Sb ternary systems were measured at 1150°C by an isothermal isopiestic method to obtain fundamental information about the behavior of arsenic and antimony in processing intermediate products and cobalt arsenide or antimonide ores. Phase relations between the solid solution and liquid phases in a region of dilute arsenic or antimony in these systems were also determined at 1150°C with a quenching technique. The isoactivity lines of arsenic in the homogeneous liquid phase were almost parallel to the Co-Fe axis of the Fe-Co-As ternary composition diagram, while those of antimony represented a negative gradient due to stronger chemical affinity of antimony to cobalt as compared to iron. The iron and cobalt activities in these ternary systems were derived from the measured arsenic or antimony activity and the determined phase relations. The Redlich-Kister-Muggianu polynomial formula was successfully applied to express the activities as a function of alloy compositions. Based on the obtained data, the total pressures of arsenic and antimony gas species were evaluated to discuss the possibility to recover or eliminate arsenic and antimony from the alloys by means of volatilization.

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325 Chinese copper deposits have been analyzed statistically to reveal their geological characteristics such as sizes, grades, deposit types and mineralization epochs. 10 copper metallogenic districts are listed up on the basis of specific densities of deposit numbers and copper reserves. The analyses also indicate that each district is characterized by one or two deposit types, and by one mineralization epoch. The most important deposit types are porphyry, VMS and vein. Porphyry and VMS deposits are large in size, and VMS and vein deposits are high in grade.

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