There are many types of geological formations used for CO₂ sequestration. Coal seam is one of them. The characteristics of the coal seam used for CO₂ sequestration are the methane recovery when CO₂ is sequestrated. CO₂ is injected into coal seam not only for the CO₂ sequestration but also for CH₄ recovery (ECBMR).
This paper reports the sequestration mechanism of CO₂ in the coal seam and the world R&D status in this field.
The adsorption is a main sequestration mechanism of CO₂ in the coal seam. In the field scale sequestration, pressure of CO₂ is super-critical. The adsorption volume of CO₂ in coal in that condition is not yet clarified. This adsorption volume is very important for the prediction of sequestrable CO₂ volume.
The present activities on this subject in the United States, Canada, Australia, Netherlands and Japan were reported. For the further studies, the international cooperative R&Ds are necessary. Items for the further R&Ds are summarized.

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Amount of potential resource and rate of recycling are the most important keys for sustainable development of mineral resources. Several production factors are competing each other to sustain the demand, which basically depend on population and economical environment.
Focusing on the properties of mineral resources, a long-term global model which describes the supply-demand structure of copper is developed in respect of recycling and substitution.
In this model, the production patterns and the effect of recycling to the supply are computed for over the next 150 years. The effect of substitution for copper is also simulated.
Under the assumptions of this global model, the primary supply of copper will not sustain the demand in the future. Sustainable supply for copper requires the enlargement of secondary supply by development of recycling technology.

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Knowledge of the permeability of hydraulically-tight rock at great depth is crucially important for the design and / or assessment of facilities associated with underground disposal of radioactive nuclear wastes. This paper presents a recently developed laboratory permeability test system capable of testing low permeability rocks either by using air as a permeant or by the transient-pulse method under high confining pressure conditions that simulate ground pressures at depths. The new system was used to test Shirahama sandstone and Inada granite, which are two types of rock widely available in Japan. To investigate the effects of heterogeneity on rock permeability, specimens cored parallel to and perpendicular to bedding for sandstone, and specimens cored in the direction perpendicular to Rift Plane, Grain Plane and Hardway Plane for granite, were used. The results of this study showed that: 1) gas permeabilities of a dried rock specimen tested by air permeation are almost the same values as water permeabilities of the same saturated rock specimen tested by the transient-pulse method ; 2) the intrinsic permeabilities of Shirahama sandstone and Inada granite range from about 8.3×10^-16 to 7.4×10^-17 m² and from 1.9×10^-17 to 6.4×10^-20 m², respectively. They decrease monotonously with increase in effective confining pressure (defined as the difference between the confining and pore pressures), while the rate of decrease diminishes at higher confining pressures. The reduction in permeabilities is due to the closure of microcracks that control fluid flow at low confining pressures ; and 3) Inada granite is a heterogeneous and isotropic material. Its hydraulic heterogeneity is more significant in Rift Plane than in Hardway and Grain Planes.

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In order to provide capability of intelligent control to the wheel loader, a new method for generating trajectory and controlling the bucket manipulator during scooping is proposed. In a strategic point of view, the scooping process is divided into three phases, which take place in sequence. The bucket is pushed into the piled material in parallel with the ground surface in the first phase, and then it is moved upward and forward simultaneously in the second phase. In the final phase, bucket is lifted away from the piled material. The control target and variables are designated differently in each phase. In this study, a trajectory along which the bucket tip moves is extended step by step in a regular time interval, instead of generating whole trajectory in advance before the start of each phase. The new method of trajectory generation can adapt various slope geometry of piled material without any information of the pile in advance. Fuzzy reasoning is also adopted to generate trajectories of the three actuators consisting of the bucket manipulator. The error of the current trajectory from the target that might be caused by disturbances is compensated by feed forward control. A new scheme combined fuzzy incremental generation of trajectory with feed forward control is validated by a series of computer simulation which covers scooping of nine different slope conditions of piled material.

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Though zero emission is recognized as the only and best solution for waste management with sustainability, it seems to be impossible to achieve it under current technical and social circumstances. In this paper, net cost of the emission management, which includes recycling, cascading, and disposing, was derived. Minimizing it with the constraint of the capacity of the final disposal site, the optimal portfolio of the emission management methods was dynamically derived. The problem was formulated as a nonlinear programming problem and solved with the software GAMS/MINOS. With this optimization, following two conclusions were acquired. Firstly, if the society has only two options of recycling and disposing, recycling rates must increase as final disposal site depletes. Secondly, in order to avoid this increase of the responsibility of recycling, cascading, which releases the society from the constraint of the capacity of the final disposal site, must be introduced.

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The effects of inhibitors to iron-oxidizing bacteria (Thiobacillus ferrooxidans) on the dissolution of iron species from high sulfur coal refuse (5.75 db% S) were studied in acidic solutions with the bacteria, using sodium lauryl sulfate (SDS) and tannic acid as inhibitors. Flotation experiments of high sulfur coal (4.27 dafb% S) in leachates from the refuse were conducted to remove sulfur.
Compared with tannic acid, SDS inhibited the iron-oxidizing activity of Thiobacillus ferrooxidans more and dissolution of pyrite in high sulfur coal refuse, but SDS did not prevent dissolution of soluble iron species in the refuse even at high addition rates, and pH values of the leachates were very low. When adding CaO, CaCO₃, and limecake (byproduct of sugar making), dissolution of iron was completely suppressed and the pH values were about pH 8.
Flotation of the high sulfur coal was conducted in the leachate of high sulfur coal refuse, which was prepared by Thiobacillus ferrooxidans to contain about 0.01 mol / dm³ soluble iron (almost all ferric ions) and adjusted to pH 2.5. Coal was selectively recovered as a froth product with high combustible recovery and high pyrite rejection.

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The thermodynamics of the Cu-Be-C-O system was studied in wide ranges of temperature and alloy composition, considering the importance of the minimization of Be₂C and BeO formation in Cu-Be alloy production.
The equilibrium relation of molten Cu-Be-C-O system was determined by conducting the following experiments: the solubility measurements of beryllium in molten copper under the conditions of Be₂C-C equilibrium at 1,573 ∼ 1,873 K and under the conditions of BeO-C equilibrium for normalized CO partial pressure π_CO = 0.01 and 1 at 1,423 ∼ 1,873 K. The activity coefficient of beryllium, γ_Be, in liquid Cu-Be alloys with respect to pure liquid beryllium as the standard state was also determined as a function of temperature T and mole fraction of beryllium X_Be at 1,423 ∼ 1,873 K:
ln γ_Be = {[-1 582.1 (T / K) ^-1-1.9154 log (T / K) + 7.1103] × 10⁴ (±80)} · (1-X_Be)²
+ {[1 577.8 (T / K) ^-1 + 1.9154 log (T / K)-7.1089] × 10⁴ (±80)}
Additionally, the activity of beryllium in solid Cu-Be alloys was determined by an EMF method at 973 ∼ 1,073 K to establish a partial stability diagram of the solid Cu-Be-O system.
Based on the results obtained, the operational conditions of the current Cu-Be alloy production process were also examined from a thermodynamic viewpoint. At the same time, several methods for improving the process were proposed.

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The synthesis of ferrite under hydrothermal conditions for electromagnetic wave absorption materials was investigated using the exhaust alloy sludge from the aircraft manufacturing. The alkaline suspension of precipitates containing Ni, Cr and Co in sludge and Fe(II) was oxidized by the air bubbling at 25 °C and treated under hydrothermal conditions at 170 °C for 8 h. In the product at pH 12, all the metal ions were incorporated excepting Mo into the spinel ferrite structure.
The formation of spinel ferrite structure was also attained easily by the Schikorr reaction at the comparatively low temperature. This method has the effective possibility for the synthesis of higher crystalline and large particle ferrite as compared with the traditional method, and also has the possibility for the production of higher saturation magnetization. This matter may be useful for the electromagnetic wave absorption materials.
The spinel type ferrite could be easily formed from the waste by using the mild hydrothermal conditions.

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To improve the purification process in copper electrorefining, the effect of dissolved oxygen in the copper electrolyte on the dissolution of some impurities in the anode was investigated. It is found that the dissolution of antimony can be controlled by the dissolved oxygen while it gives a small effect for bismuth and no effect for arsenic. It is considered that antimony is oxidized in a layer of the slime formed on a surface of the anode. The dissolution of antimony is influenced by lead and arsenic in the anode, and the dissolution is accelerated when the arsenic content in the anode was between 0.1 and 0.2 % while it is decreased with the increase of lead content.
The electrowinning by means of pulse electrolysis has been proposed as the most effective process for generating the dissolved oxygen.
Controlling the dissolution of minor elements in the anode is a kind of purification, and the impurities can be controlled by suppressing their dissolution with a help of the dissolved oxygen. The proposed process has an advantage as it can be operated without any special equipment.

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The internal structure of Ag-NiO composite powders prepared by the spray pyrolysis was investigated by a microscopic analysis of the microtome section with a transmission electron microscope and a field emission scanning electron microscope. Further, the crystallite in the Ag-NiO composite powders was examined in detail by the electron beam diffraction and EDS analyses to determine the microstructure.
The internal structure of the composite powders consists of Ag layer in the external region and Ag-NiO composite structure in the core region. It is guessed that the Ag layer in the external region is formed by a single crystal or a few crystallites from the results of the electron beam diffraction. In the core region of composite powders, Ag particles and NiO particles are found as crystallites of a single crystal, which are confirmed respectively by EDS and electron beam diffraction analyses. The particle size of NiO measured by TEM is about 20 nm. It is in good agreement with the crystallite diameter of NiO which is calculated from the half-power band width of X-ray diffraction.

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