The shaft ore pass system of Garou quarry with an inclined shaft and that of Toumi quarry with a vertical one have the same chute and hopper layout. Their shaft diameters are approximately equal and also are the size distributions of the dumping muck. The quantitative influence of the mixing proper to the inclined shaft has been made clear by the mixing property measurements of these ore pass systems. A single parametric linear function is proposed to describe the velocity field in this part. The calculated mixing property curve based on this velocity field can be well fitted to the mixing property of the additional mixing in the inclined shaft. Also a formula describing the velocity field in the funnel flow region, that is common for both ore pass systems, is proposed. Accordingly, it became possible to estimate the mixing property of the future Garou system with a shorter shaft.
Based on the mixing property curve, the effective capacity of the ore pass system is estimated. Also the dilation mechanism of the shaft is discussed. The theoretically estimated relationship between the shaft diameter and the accumulated production based on the assumed mechanism can be well fitted to the experimental results.
Equation that gives the quality variation of the product from the step-functional input quality variation and the mixing property has been deduced. Based on the case study of the Garou quarry, it is certified that the maximum quality variation of the product depends on; 1) the dumping order of the ore block in a unit lot, 2) the scale of the unit lot, and 3) the mixing property of the ore pass system.

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An experimental apparatus based on the transient hot wire comparison method was built for measuring the thermal conductivity of both water-saturated and-unsaturated rocks. A new method was developed for determining the time range necessary for calculation of the thermal conductivity in order to measure it accurately. The range is determined by using the second derivative of the hot wire temperature with respect to logarithm of time.
The thermal conductivity of water-saturated rocks was measured in a water bath as well as in an airconditioned room. The measurements of the thermal conductivity of water-unsaturated rocks were also made in the same room. The thermal conductivity is able to be measured both in the water bath and in the room within ±5% accuracy in a wide range of 0.05 to 15W/(m·K). For measuring the thermal conductivity of water-saturated rocks, the steady state condition required as initial condition can be easily obtained in a water bath.

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Three-phase gas-liquid-solid flow phenomena in pipes are observed in air-lift pumps for transporting solid materials, coal liquefaction plants, and so forth. In analyzing or numerically simulating three-phase flow phenomena, one needs a set of basic equations which describe the conservations of mass, momentum and energy for three-phase media.
The purpose of this paper is a formulation of the basic equations in three-phase flow for practical applications. The derivation of the equations was carried out for the mixture model in neglecting the interfacial force and energy. First, using a characteristic function of each phase in the mean of distribution, the physical parameters of three-phase flow were defined as field quantities, and then the local instantaneous and averaged conservation equations of mass, momentum and energy were derived. Secondly, taking radial distribution of the physical parameters into account, one-dimensional basic equations were represented by means of the drift flux model on the basis of the local averaged equations.

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Generally, many tensile cracks could develope derivatively along a large fracture generated mechanically in the coal seam ahead of a working face when high pressure gas is confined in micro pores and micro cracks and gas is almost impermeable. Gas pressure in the fractured zone increases intensively owing to free gas from the micro pores and the micro cracks, when the chain reactive fracturing occurs in a coal seam. Generation of these fractured zones must be a cause of coal and gas outburst.
In this research, scale model experiments were carried out by using the rosin including numerous micro pores saturated with high pressure gas in order to ascertain the occurrence of the phenomena above mentioned. As the result of the experiment, it was confirmed that both the tensile fracturing and gas outburst occurred as predicted.

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For economizing in grinding process, a new type mill, a single rod mill, developed from a roller mill and rod mill was produced as an experiment. The ability of the single rod mill was investigated by various grinding experiments. Samples used were quartz with five kinds of size ranges. As a result, it was found that feed size for this mill was far larger than that for conventional ball mills, and that product with uniform particle size was obtained relatively. The grinding mechanism in this mill was found to be compressive grinding by the load of a rod.
The mill with construction such as a single rod mill in this work is usefull enough as a fine grinding machine.

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Ball-race mills form one of the most widely used types of industrial grinding device, employed especially for dry fine grinding of coal. Grinding rates and efficiencies of these mills decrease with build up of fine ground powder. In this study, grinding mechanism of coal by a Hardgrove mill, a representative ball-race mill, was analyzed by using a dead space model combined with a non-linear mean squares fitting technique. As a result of the analysis, slow mixing of coal powder in the mill presumably due to poor flowability of the powder was found to be responsible for slowing down of grinding rates which results in inefficient fine grinding of coal by Hardgrove mill. Based on the result, grinding additives which can improve the flowability were selected and tested by a milling experiment. As a result, calcium stearate and carbon black were found to be most effective for fine grinding of coal by Hardgrove mill. Furthermore, action mechanisms of some additives were analyzed by using the dead space model.

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The strength and grindability of copper smelting slag produced by water quenching have been investigated in the framework of single particle crushing and corrective grinding tests. X-ray diffraction analysis clearly indicated that the slag samples are the mixture of glassy and crystalline components, such as fayalite and magnetite. The amount of crystalline component of as-quenched samples increases as the particle size increases. The particle compressive strength of 10-20μm diameter particles of a sample mainly composed of glassy component appears to be almost twice as high as that of a sample including a large amount of crystalline components.

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To elucidate some basic properties in the fundamental antimonide speiss systems, activities of the component elements were determined in the Pb-Fe-Sb and Pb-Cu-Sb ternaries at 1, 200°C by the transportation method.
In the Pb-Fe-Sb system, the activity of antimony exhibits a slightly negative deviation from ideality for the entire composition range. A negative deviation of antimony activity is also seen from the additivity of the Pb-Sb and Fe-Sb binaries. In the two phase region, the activity of antimony ranges from 0.16-0.35, which is relatively large in comparison with arsenide speiss, suggesting a less stable speiss than the arsenic system. Lead activity on the other hand is below 0.77, indicating that gold and silver extraction by lead may be minimal.
In the two phase region of the Pb-Cu-Sb system, antimony activity is below 0.1, displaying a large negative deviation from Raoult's law, while the activity of lead is greater than 0.75, comparatively larger than in the Pb-Fe-Sb system.
Based on the interaction parameters determined in this study, the activity coefficient of antimony in molten lead containing minute amounts of copper and iron may be expressed as follows:
InγSb=-0.422+0.08X_Sb-2.6X_Cu-X_Fe

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