Equilibrium moisture content of activated aluminas, active carbons, activated clay and so on was measured at a temperature ranging from 10 to 50°C. The experimental results were shown in Table. Furthermore, the temperature dependence of equilibrium moisture content was discussed.
Results obtained are as follows:
1) The values of equilibrium moisture content are smaller than those of water vapor adsorption, and both curves are parallel as shown in Fig. 2.
2) In both processes for increasing and decreasing humidity, the temperature dependence of the moisture content of activated aluminas and activated clay is illustrated by plot of the equilibrium moisture content as a function of adsorption potential.
3) Plots of W_e/ρS vs. adsorption potential fall on a curve as shown in Fig. 5. The curve is independent the kinds of materials and of the temperature in the low humidity region in which no capillary condensation takes place in a pore. This fact can be used for estimating the equilibrium moisture content.

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A numerical simulation calculating motion of individual particles was attempted for pneumatic conveying in the case of the presence of pipe branching. First, this paper summarizes the present method of simulation established for pneumatic conveying in a straight pipe and then explains coordinate transformation which must be made at the branching point. In the simulation the particles are assumed to be spherical, and the effects of friction between the particles and pipe wall which occur at the moment of collision are calculated by the use of Coulomb's law. Calculation was made in accordance with the conditions of a previous experiment in order to compare the results directly. As a result, it was found that the present method gives a good agreement with experiment so far as particle distributions are concerned. The calculated distributions of additional pressure drop along the pipe show qualitatively the same tendency as the measurements, but quantitatively the calculated values are several times larger than the measured ones.

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The potential distribution profiles in a naturally charged fluidized bed have been measured for various particle materials, particle sizes from 200 to 540μm under humidity controlled conditions of 5 to 65% for acryl and iron towers of 6.7cm in diameter. In addition, the potential on the inner surface of the acryl tower was first observed by installing five proves at different heights.
It has been observed that the acryl tower as well as the bed could be highly charged up to ten kilo-volts. From this measurement, the main charge source of electric potential that happend to be detected in previous works was reasonably confirmed. For the purpose of reviewing the measurements included in the present work, numerical calculation of potential distribution profiles has been done by the ordinary iteration method. Comparison shows that the present potential measuring technique still has some defects which need to be improved. Nevertheless, measured values seem to be valid, at least, as far as their order is concerned.
Besides this, calculated result gives an insight into dead space and channelling formation due to the electrostatic adhesive force. It can be emphasized that the electrostatics generated in a fluidized bed will cause irregular fluid motion for a large scale bed with nonconductive particles.

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The authors proposed a new method of fluidized bed drying using microwave heating. In this method, the microwave directly heats the moisture within the wet granule, and the fluidized bed is formed by wet granules so that they will be irradiated uniformly by the microwaves.
The temperature of outlet air was roughly in proportion to generating power during a constant rate period of drying. At the folling rate period of drying, the temperature of outlet air increase quickly.
The heating rate of water by microwave power agreeded very closely with the calculated value from generating power when 1kg of water was used.
It was necessary for high thermal efficiency to add generating power corresponding to the moisture content contained in the drying materials. The relationship between the fluidizing air rate and the constant rate of drying gave a straight line on log-log graph paper the rame as the characteristic of a usual fluidized bed.
It was clarified that granules were dried uniformly and rapidly by this drying method.

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It is experimentally confirmed by the use of two small cylones and four kinds of test dusts the way in which the inserted length of exit pipe affects cyclone perfomances. When the inserted length is nearly zero, the collection efficiency remarkably deteriorates. But if the length is more than one fifth of the cyclone inlet height, the performance change is small. The pressure losses of cyclones only decrease slightly, even if the inserted lengths are zero.
However, the particle size distributions of emission dusts from cyclones approach those of feed (inlet) dusts as the inserted lengths decrease. For no inserted length, the both distributions coincide with each other, and no classification takes place in a cyclone.

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