There are growing markets for activated carbon for such purposes as water treatment and air pollution control. Although these new markets are not developing as fast as expected, the ultimate potential is considered to be huge. Therefore, intensive research is being conducted in the field of production of activated carbon to develop a new manufacturing process or to seek new kinds of raw materials. Under these circumstances we have developed the new manufacturing technique for the production of spherical activated carbon from coal, which may be promising as effective adsorbents for pollution control.
The manufacturing process of the activated carbon from coal consists of five steps. They are pulverizing of coal, pelletizing of fine coal, precarbonization, carbonization and steam activation. The choice of raw coal species is very important to produce good spherical activated carbon. Coking-coal with a carbon content of 80-85% has proven to be a good raw material. After pulverizing, the coal is pelletized into spherical particles with a disk-type pelletizer. In this process, particle size distribution of the fine coal, water content, kind and amount of binder added all influence the pelletizing effect. To obtain strong and dense spherical carbon, carbonization is carried out at a temperature of 500-600°C at heating rate of 0.5-5°C/min. It appeared that an indirectly heated rotary kiln is the most suitable carbonization apparatus. The carbonized pellets are activated with steam. Spherical activated carbon exhibiting a high adsorption property and strength can be prepared with an indirectly heated rotary kiln or directly fired rotary kiln in the presence of limited quantities of oxygen.

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In order to discuss the safe limits of blasting vibrations for residential structures, it is necessary-to know the magnitude of structure's vibrations. But, it is a troublesome thing to measure the vibration of structure, comparing with the measurement of ground vibrations. Therefore, the response spectra which can be calculated from the measured ground vibrations become a useful information to discuss the effects of blasting vibrations on structures.
In this study, the vibrations produced by instantaneous, millisecond delay and two rows decisecond delay bench-cut blastings were measured both on the structure and on the ground near it. Then, the vibration data were analyzed and the response spectra for each blasting condition were calculated from the measured ground vibrations. As the results, the resonance frequency of most sensitive structures for blasting vibrations, and also the degree of excitation of structure's vibrations against ground ones were obtained.

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This report is concerned with the effects of capsule/pipe diameter ratio, capsule length/diameter ratio and capsule.
specific gravity on the drag coefficient of capsule.
A drag coefficient of capsule can be theoretically and experimentally expressed by a function of l/(1/d-1) R_e, where l is the capsule length/diameter ratio, d the capsule/pipe diameter ratio and Reynolds number R_e; R_e=U_md/ν, in which U_m is the mean fluid velocity at the leading edge of capsule, and ν the diameter of capsule and the kinematic viscosity of the fluid.

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Two ferrite permanent magnets fixed on an iron yoke were arranged with suitable distance and angle. A nonmagnetic body placed in a magnetic fluid between these magnets receives a magnetic levitation force towards a minimum point of magnetic field. Thus the magnetic fluid could be regarded as dense medium suspension of high specific gravity.
We reported about the separation of glass and porcelain in the first paper “Sink and Float Separation with Magnetic Fluid”. However, ceramic particles smaller than 5mm in diameter couldn't be separated satisfactory. Here, the relation between particle size and separation efficiency was investigated. Sphalerite, Pyrite and Galena whose size was from 3 to 100 mesh were used. Specific gravities are about 4.5 and 7.5 respectively. A water-base magnetic fluid was used as a medium.
When put into this fluid, the mixture of those nonmagnetic minerals separated, except for particles smaller than a certain size. It was found that the lowest limit of the separation size depended upon the difference of specific gravity of them. And the smaller the difference was, the larger the limit size was. The principal reason for nonseparation of fine particles is that each nonmagnetic particle in the magnetic fluid under a magnetic field adheres to each other in the direction of the line of magnetic force. However, they repulse each other when positioned along the vertical direction of the line of magnetic force. In order to use this repulse force, we therefore constructed trial equipment to separate adhered particles by turning the cylinder in which the particles were placed in the magnetic fluid. As a result, we were able to separate the major portions of Pyrite and Sphalerite particles larger than 100 mesh size.

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Molten Cu-Sb alloys were brought to equilibria with silica-saturated iron silicate slags at 1200 and1250°C in atmospheres of controlled oxygen pressures. No entrained alloy was found in the slags. Copper and antimony were found to dissolve inthe slags in the forms of both oxides and atoms. It was shown that CuO_0.5 and SbO_1.5 were thermodynamically mostf easible forms of the oxides in the slags. The activity coefficients of Cu, CuO_0.5, Sb and SbO_1.5 in the slags were calculated. The oxygen potential in the molten slag was mainly determined by the oxygen formed by the decomposition of the silica crucible when the oxygen pressure in the gas phase was less than a limiting value at each temperature.

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(1) In the vertical refining process developed by New Jersey Zinc Co., the mechanism of the removal of the highly volatile metal (Pb) by the rectification was examined quantitatively.
The hypothetical model of the refining process could explain successfully the actual operation data. It will, therefore, be very useful for the design and modification of the lead column.
(2) Lead content in the refined zinc metal from the lead column and the zinc production rate are calculated, as an example, in accordance with respective number of boiler trays and reflux trays.

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Pyrite cinder can be used as a source for iron smelting by removing the impurities such as copper, zinc, etc.
The chloridization and sintering treatment was carried out using three kinds of pyrite cinder whose kind and roasting condition were different. Volatilization percentage of valuable metals, the crushing strength ratio (crushing strength of calcined pellet/crushing strength of drying pellet at 100°C) and the apparent specific gravity of pellet were measured. Mineralogical forms of sintering pellets were also discussed by XMA analysis.
The experimental results are summerized as follows;
(1) Volatilization percentage of Cu, Pb and Zn in pyrite cinder amounts to constant value when heating temperature is above 1100°C, and the volatilization percentage of Pb is the highest for all pyrite cinder. However, in order to use as the material for iron blast furnace, heating temperature shall be desired above 1200°C considering amount of residual S and Cl in pellet.
(2) It was clarified that the kinds of pyrite cinder had influenced on volatilization percentage. As the crushing strength ratio of pellet was greater, the volatilization percentage was inversely lower.
(3) Volatilization percentage is increased by slow heating as compared with rapid heating. However, when heating temperature is 1300°C, this effect is not observed in evidence. When the air flow is an optimum condition, the highest volatilization percentage is obtained and it is closely related to the crushing strength ratio and the apparent specific gravity of pellet.
(4) The relation between compound form of valuable metals in pyrite cinder and roasted pellet was clarified by XMAanalysis. The ring layer was formed by CaCl₂ during chloridization process, it was discussed that formation of this ring layer was the parameter which indicated the degree of chloridization and sintering of pellet.

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