The effects of pulsating motion induced in conveying air and vibratory motion applied to a pipe wall on power consumption in pneumatic conveying of granular materisla were examined experimentally. The experiments were performed using a horizontal pipe 4.2m in length and 52mm in diameter and millet grain as the conveyed material.
It is concluded that the application of pulsation to air and vibration to pipe are effective in reducing the power consumption. The power consumption is tolerably reduced compared to that for an ordinary dense-phase type of pneumatic conveying.

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Viscosity of gaseous R-22 was measured using an oscillating disk viscometer of Maxwell type at 273.15-398.15K in the pressure range up to 60×10⁵Pa. An empirical equation was obtained to represent viscosity at normal pressure as a function of temperature. Force constants for Lennard-Jones 12-6 potential were determined from observed viscosity values at normal pressure as follows: ε/k=214.8K, σ=4.971×10^-10m.

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In this work, the activity of alcohol (methanol, ethanol, 1-propanol and 1-butanol) in alcohol-calcium chloride solutions at 25°C was measured by use of an apparatus based on a flow method coupled with gas chromatography. Further, the ASOG model in conjunction with the solvation model, which has successfully been applied to estimate the activity of water in aqueous electrolyte solution, is extended to correlate the activity for alcohol in an electrolyte solution. As a result, it was found that the activities of some alcohols in alcohol-calcium chloride solutions can be correlated up to concentrated regions near the saturation concen- tration.

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Rheological behavior of some dispersed systems of solid particles from rest to steady flow state was examined by the side-view visualization of deformation and flow profile in a cone-and-plate type rheometer. Not only steady rotational speed but also acceleration rate of rotation of the plate were controlled precisely. Samples used were γ-goethite, calcium carbonate, and Kanto-loam, dispersed in water and waste sludge. They could be classified into either plastic or elasto-plastic body according to their solid-like behavior. Common behavior for both the bodies is that only a part of the sample layer yields and that the stress increases further after yielding and then is reduced in a thixotropic manner, passing through a maximum. The maximum value of the stress increases with increasing acceleration rate of rotation.

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In two-deimensional and three-dimensional gas-fluidised beds of binary particle mixtures, cine-photographic measurements were made on the solids ejection phenomena induced by bubble eruption. Fine particles concentration in the bed and their elutriation rates were also measured. It was experimentally shown that fine particles contained in the bulge region are projected into freeboard and elutriated. Further, from the similarity of dependence of the estimated ejection mass flux based on this mechanism and of the measured elutriation rate on the bed height, the ejection mechanism of fine particles from the bulge region is also supported.

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Two-dimensional freezing problems with heat conduction in cooling walls were analyzed by the finite element method and simulation experiments were carried out.
In the first step of the analysis, heat transfer in solid and liquid phase was treated as pure heat conduction. The calculated results of the freezing rate and temperature distribution in the solid phase approximately agreed with the experiments. However, the experimental study revealed that the temperature profile in the liquid phase was uniform due to natural convection. Thus a modified model was proposed by assuming complete mixing in the liquid phase. This assumption was proved to be useful for predicting the freezing rate and temperature distribution in solid and liquid phase.

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An experimental and a theoretical study of gas-phase multicomponent mass transfer under condition of high mass flux were performed, for the simultaneous chemical absorption CH2NH3 and of NH3 in a wetted-wall column.
It was found that interaction between. diffusion fluxes in the multicomponent system becomes more significant with increasing concentration of absorbed gases and tends to promotemass transfer. High mass flux and density-driven convection also have strong influence onthe transport characteristics.
Considering the variation of physical properties, the change of flow rate and multicomponent diffusional interaction, the momentum and diffusion equations were solved by the finite difference technique. The calculated mass transfer rates coincide with the experimental ones.

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The application of sponge ball cleaning to prevention of scale in a multi-stage flash evaporation-type desalination plant was tried. Sponge ball cleaning is a mechanical tube cleaning method that has been put into practice in the surface condensers of thermal and nuclear power plants.
The scale prevention effect of sponge ball cleaning was investigated in a 100m3/d-capacity, 10-stage flash evaporation plant. It was found that the scale release rate by ball friction was inversely proportional to deposit thickness, and that the removal of scale was insufficient because of high scale deposit rate.
Sponge ball cleaning combined with pH control, in which 50 percent decarbonation of feed sea water was done by partial acid dosing, showed good effect in prevention of scaling and corrosion.

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The mechanism and kinetics of thermal decomposition of calcium chloride mixed with various solids such as silica, alumina and titanium oxide were studied at 1 atm and 873K to 1143K. Calcium chloride tends to dissolve into the cage of solid acid at a temperature lower than its melting point. It then decomposes to generate hydrogen chloride in the presence of steam and chlorine in the presence of oxygen or air. The decomposition rate is first-order with respect to the concentrations of both silica and calcium chloride and one-half order to oxygen or steam. The activation energy is 89.0kJ/mol for hydrogen chloride and 70.2kJ/ mol for chlorine. This involvement of silica in the decomposition of calcium chloride has a common feature with the decomposition of chlorides and carbonates of other alkaline metals and alkali earth metals.

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This paper describes methods of improving the performance of a new pneumatic classifier based on the rapid classification principle.
The following results were obtained.
1) By sucking part of the clean air into the fines side, recovery of fine particles was much improved.
2) Hanging one side of the wall of the inlet duct for particle-laden air over one side of the wall of the out-let duct on the coarse side, the entrainment of coarse particles into the fines side was effectively suppressed.
3) By combination of 1) and 2), the sharpness of classification was improved remarkably.
4) The sharpness of classification can be maintained up to a particle concentration of 0.2kg/m³.

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An approximate expression for single-sphere collection efficiency due to diffusion and interception was obtained theoretically by using the Tomotika-Aoi flow field around an isolated sphere for viscous flow (N_Re<<1).
The coefficients of the expression were experimentally modified to obtain a semi-empirical formula for granular-bed gas filtration, as a function of Peclet number N_pe and interception parameter N_R. Another empirical expression which took account of Reynolds number N_Re as well as N_pe and N_R was also proposed.
Both expressions not only well described the present experimental data in the range of filtration velocity U_s=0.2-20cm/s, aerosol particle diameterD_p=0.31-2.0μm and packed granule diameterD_c=88-4300μm, but also agreed fairly well with the data reported by several investigators in the diffusion-predominant region.

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The effect of charge density of cationic polymer flocculants on flocculation was investigated for dispersions of negatively charged polystyrene latex particles, and the flocculation mechanism was estimated. It was found that particle charges are neutralized at the maximum flocculation concentration (mfc) determined by the jar test and that the rate of Brownian flocculation at the mfc increases with the charge density of polymers. And it is indicated that the flocculation is attributed mainly to the charge neutralization of particles by polymers and partly to the configuration of cations on the particle surface.

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The unconfined two-dimensional expression of semisolid material in a tube-type press, where the material is compressed on a cylindrical filter element, is investigated under constantpressure conditions. An equation for analysing the expression rate is presented by introducing a newly defined value of effective consolidation area factor j_II. To evaluate the area factor j_II for constant-pressure expression of homogeneous semisolid material, the basic consolidation equation based on the Terzaghi's model is solved, and a simplified equation is derived in terms of the ratio (D_o/D_i) of the outer to the inner diameter of the original material. It is demonstrated that the area factor j_II can be calculated with sufficient accuracy to adequately estimate two-dimensional expression processes. A logical method for predicting the dehydration in a tubular press is shown, in consideration of the fact that the deliquoring rates of two-dimensional expression are larger than those of conventional one-dimensional expression by the factor (j_IIII2-1).
Satisfactory agreement between theory and experiments is assured under the conditions of technical interest, where the ratio (D_o/D_i) ranges up to 2.0.

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Two hollow-fiber reactor systems in series were optimized with respect to the yield of ammonia in the sequential reactions by arginase and urease, decomposing arginine to ammonia via urea. In this optimization, partition of the two enzymes and pH values were used as the control variables.
In the lower range of conversion with higher concentration of substrate and short residence time, a policy of keeping pH optimal for each enzyme reaction separately in the two reactors without partitioning the enzymes is advisable for obtaining maximum yield. Meanwhile, in the higher range of conversion with lower concentration of substrate or long residence time, the optimal partition of the two enzymes in each reactor, having pH value optimized consistently throughout the two reactors, is recommended. Experimental data are presented to justify the optimal strategy studied here.

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