An explosive operation for the effective utilization of biomass was studied experimentally with Larix leptolepis under various operating conditions of steam pressure from 1.08 to 4.81 MPa and reaction time from 1 to 20 min. Size distribution of exploded wood was described by the Rosin-Rammler equation. The products were separated into hemicellulose, cellulose, methanol-soluble lignin and Klason lignin. The effects of operating conditions on the characteristics of exploded wood were studied from the experimental data of shape and size of exploded wood, amounts of extractive components and enzymatic hydrolysis rate. The equation for saccharification of exploded wood is expressed as a function of steam pressure, reaction time and enzymatic hydrolysis time.

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The regeneration of water-loaded zeolite in superheated steam followed by the adsorption of water vapor in dry air was studied experimentally for designing an apparatus to produce water from dry air in desert areas. The following conclusions were reached :
1) A simulation of the adiabatic adsorption process after steam regeneration predicted well the experimental results; the temperature of the zeolite bed approached a plateau temperature, independent of residual water content and regeneration temperature, which can be estimated by Pan's equation.
2) The equilibrium water content measured in an atmosphere of superheated steam at temperatures above 573 K agreed well with the values calculated by Polanyi's equation, but became smaller than the calculated values at lower temperatures.
3) The heat transfer coefficient between the superheated steam and the zeolite was estimated from the experimental desorption rate to be about 2.3 W/m²·K at a mass velocity of 150 kg/m²·h, which agreed with the value calculated by Hyodo's empirical equation.
4) After 1, 000 times of regeneration with superheated steam at 623 K, the equilibrium adsorption capacity of the zeolite was decreased by about 15 % compared to that of virgin zeolite, and no significant change was observed in the X-ray diffraction pattern of the used zeolite.

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The development of an efficient electrostatic coalescer for the demulsification step is highly desirable in the practical application of the liquid surfactant membrane process. In this study, demulsification experiments with W/O emulsions were carried out by application of pulsed DC high potential. The effects of operating conditions such as the applied potential and forming conditions of W/O emulsions on the demulsification rate were investigated.
The present method of applying high DC electric potential was found to be very effective in the breaking of W/O emulsion. The fundamental information obtained here is usable for developing a continuous demulsification apparatus.

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Power consumption and flow rate of a three-roll mill for Newtonian fluid were investigated. Feed and apron nip clearances were measured by a non-contact displacement transducer inserted in a center roll. The experiment was carried out under various conditions of nip clearance, roll speed, roll speed ratio, fluid viscosity and bank width.
The power consumption was well correlated by an equation derived by applying the results for a two-roll mill to a three-roll mill. A simplified equation for power consumption could also correlate the experimental values. Flow rate through the mill was obtained from an equation of material balance. It was found that the apron nip clearance could be estimated with the feed nip clearance and roll speed ratios when the mill was operated in a steady condition.

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Electrochemical characteristics of a rectangular fluidized-bed electrode (RFBE) with coppercoated glass particles (diameter 2.12 mm) were studied using the electrodeposition of copper from an acidified aqueous solution containing 0.1 mol.dm^-3 of CuSO₄. Two electrolytic cells of different sizes were used in the experiments, both of them having a cross-sectional area of 0.34 dm² in the direction of current flow and respective bed thicknesses of 1.8 cm and 3.7 cm.
Apparent current densities of the RFBE were calculated by using the total electrode area (the sum of the surface area of the fiat cathode and that of total particles). Current density-overpotential curves of the RFBE were expressed by these current densities and the overpotentials measured at the fiat cathode. By using these curves and the local overpotentials within the RFBE, the reaction current at the surface of the particles was estimated quantitatively. The estimated values of the total reaction current agreed with the experimental values of cell currents within an error of 1015%.From the reaction current distribution along the RFBE thickness it was seen that the more active particles acting as cathode were distributed in a distance of 0 to 10 mm from the fiat cathode and in the vicinity of the diaphragm.

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The steam and power system was formulated by a linear model of the continuous variables and binary (0-1) variables to obtain the optimal operation under discontinuity in the operation of units and nonlinearity of the process characteristics. The problem of finding the optimal operation to meet the system specifications became a mixed integer linear programming (MILP) problem. The robustness of the optimal operation, that is, the variation of the optimal solution by changes in the coefficients of the objective function and/or in the parameters included in the system constraints, was analyzed on the basis of geometric consideration of the MILP problem. As an illustration, the robustness of the optimal operation for an existing steam and power system was studied under various situations.

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To determine the feasibility of anodic depolarization with coal slurries, leaching of iron and sulphur from coals and reduction of ferric ions with coals were carried out with different coal samples. Most of the iron in the coals other than pyritic iron was leached into 4 kmol m^-3 H₂SO₄ solution at 323 K. When pulverized Illinois No. 6 coal was mixed in a solution of 1 kmol ·m^-3 HCl+ 0.89 kmol ·m^-3 Fe³⁺ at 383 K, inorganic sulphur was totally leached, and 0.77 kmol ·m^-3 of ferric ions was reduced.
Next, long-time electrolysis of coal slurries was conducted in an H-type cell equipped with a rotating-paddle anode of platinum-plated titanium. The reactivity of coal slurries with Fe³⁺ increased with decreasing carbon content in coals. However, the current density remained at low levels.
When a packed-bed electrode cell with graphite felt packings was used, a current density as high as 1000 A ·m^-2 was obtained at 1 V. The anolyte was a filtrate of Illinois No. 6 coal slurry which was stirred at 323 K for 2 h in a solution of 4 kmol ·m^-3 H₂SO₄ + 1 kmol.m^-3 Fe³⁺. No deactivation of the anode was observed during the electrolysis.

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The effect of particle size distribution on the viscosity of highly loaded coal-water slurries was analyzed both experimentally and theoretically. As qualitative agreement between experimental and theoretical results was obtained, a search for the optimum particle size distribution of CWM (Coal-Water Mixture) to minimize the slurry viscosity was carried out, using the same theoretical treatment. The two-stage pulverizing system was adopted as the CWM preparation process. The optimum particle size distribution obtained in this work was a bimodel and continuous distribution which had two peaks. at 1.3 μm and 140 μm. This particle size distribution was obtained by mixing 20-30 wt % of very fine particles into the coarse particles. The possibility of realizing the optimum or semi-optimum particle size distributions was studied in relation to the experimental results of viscosity measurements of highly loaded CWM.

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A method for evaluating catalysts in the reaction of hydrocarbon with catalyst deactivation has been investigated by the use of the isomerization reaction of ethylene oxide over silica-alumina catalysts of different compositions and properties. Because the coke deposition had a large influence on the main reaction as an inhibitor, it was not an appropriate method for evaluating the catalytic strength from the main reaction only. The over-all effective catalytic strength with the inhibition reaction taken into account was therefore defined in terms of r_A0α_C/r_C0α_A as a function of initial rate and deactivation coefficient. The evaluation of catalyst was carried out by this value. After investigation of its adaptability, there was a good correlation between this value and catalyst life, total amount of acetoaldehyde product formed during the catalyst life. It became clear that this value permits a kinetic evaluation of the catalyst.

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When a dense powder bed in a bin charged by peripheral feeding flows down, there occurs a pulsating fluctuation of wall pressure in the upper part of the bin's hopper section. This phenomenon is considered to be due to the formation of arching at the level, which controls so that the dense powder bed in the hopper section can flow down easily. On the other hand, a loose bed charged by central feeding forms complete mass flow without pulsating pressure fluctuation. By assuming that the formation of arching is caused by excess of powder mass in the dense bed in contrast to the loose bed by central feeding, the zone for pulsation of wall pressure in the hopper can be estimated.
As a result, it was found that : 1) In the case of a critical mass flow such as occurs when flow type changes from funnel flow to mass flow during discharge, the zone of pulsating pressure reached to roughly one-third the section from the transition of bin-hopper system; 2) the zone size was reduced and the pulsation was restricted at the transition as the hopper angle became sharp.

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A simple viscosity correlation over a wide region (0.33_??_V_r_??_100, T_b<T<T_c, 0.1 MPa < P<P_c) is proposed. This correlation contains four parameters and their optimum values for 22 substances were determined from reference data. Among the four determined parameters, a molecular size parameter was correlated with liquid volume at normal boiling point. Two parameters of the remaining three were fixed as constants for three substance groups : inorganics, hydrocarbons and fluorocarbons. Thus, the proposed correlation became a one-parameter viscosity correlation. In viscosity calculation, averages of root mean square of deviations (RMS) of the proposed one were, respectively, 6.84 % and 6.96 % for vapor and liquid regions. Since RMS of Jossi-Stiel-Thodos' correlation was too large (22.87 %) in the liquid region, the deviation of liquid viscosity of the proposed correlation was compared with the other three for liquid viscosity. As a result, the deviation of the proposed correlation was comparable to that of Ototake and was superior to that of Li-Poole and Goletz-Tassious.

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For the purpose of thermal energy storage at relatively low temperature around 373 K, the following gas-solid reaction cycle in which both an exothermic (hydration) and an endothermic (dehydration) process are involved was chosen and was studied from a fundamental point of view concerning its reaction equilibrium and reaction kinetics by using a micro-thermobalance equipped with a steam generator.
CaSO₄+1/2H₂O _??_ CaSO₄·1/2H₂O + 115.6kJ/kg
The grain model was applied in order to determine the reaction kinetic parameters such as the reaction rate constants by considering a complex reaction scheme during the course of the hydration of CaSO₄ and the dehydration of CaSO₄·1/2H₂O. As a result, it was found that the reaction order with respect to the steam pressure was 1.0 for both the hydration and the dehydration, and that the reaction rate constant for the hydration of CaSO₄ took a maximum value at about 380 K. Further, it was observed that the reaction activity remained almost constant, independently of the repetition of the reaction cycle between hydration and dehydration within the experimental conditions employed.
Consequently, it is considered that the CaSO₄ · 1/2H₂O/CaSO₄ thermochemical reaction cycle might be usable for thermal energy storage between 293.2 and 473.2 K, despite its relatively low value of reaction heat among several kinds of reaction candidates.

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Experiments on liquid-liquid dispersion were performed by using a loop reactor. The size distribution and mean diameter of droplets formed in the reactor were measured. The droplet diameter distribution was a log-normal distribution and the mean diameter decreased exponentially with mixing time.
In the circulation region of the reactor, coalescence and breakup of droplets were thought not to occur essentially. Accordingly, the size distribution or the mean droplet diameter was found to depend strongly on the energy dissipation rate in the impeller region. The minimum transition time required to reach steady-state was proportional to the 0.3th power of the Weber number in the impeller region.

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Bed compaction is often observed in packed beds containing gel particles of immobilized enzymes. Decrease of conversion due to this compaction phenomenon was studied experimentally. When the enzyme reaction was first-order, the decrease of the effectiveness factor of particles could be explained by the Thiele modulus, void fraction and the Biot number. The higher the Thiele modulus, the larger was the effect of compaction on the effectiveness factor. And this effect became notable as the extent of compaction became considerable. Also, the effect of film mass transfer resistance was found to be considerable when calculating the apparent effectiveness of the immobilized enzyme reactivity.

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To study the vibration effect on the movement of particles, two kinds of experiments with the tilted board and the wind tunnel were carried out.
The friction coefficients calculated from the transfer threshold conditions were smaller than those from the critical friction velocities.
The friction coefficients decreased linearly with the increase in acceleration ratio of the vibration.
Under vibrating conditions, the dimensionless critical tractive force had its minimum value at a certain Reynolds number.
The vibration effect on particles in the air flow had its maximum value at a certain ratio of the particle diameter to the laminar sublayer.
Suitable conditions for conveying granular materials under vibrating conditions were clarified fundamentally by this study.

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The objective of this study is to obtain some basic information on the reduction of power consumption for the pneumatic conveying of granular materials in an inclined pipeline.
To study experimentally the vibration effect on the pipeline under vibrating conditions, a pipeline consisting of a section of 50 × 50 mm and a length of 4100 mm was tilted up and down to some degree.
The transport efficiency was improved by applying the vibration to the horizontal or downward-sloping pipeline and had its maximum value at a certain value of the acceleration ratio.
For the upward-sloping pipeline, the vibration gave a contrary effect except for high-concentration transport such as the plug flow.

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