With the recent diversification of foods, various liquid foods are increasingly being sterilized by plate-type heat exchangers. However, the heat from plate-type heat exchangers often causes the liquid foods to adhere to the heated surfaces due to heat denaturation. This results in fouling of the surface of the plates, which affects their operations and causes serious technical problems. Therefore, the authors investigated the heating of various types of liquid foods by plate-type heat exchangers as a basic study of long-run, continuous heat sterilizing processing. In this research, the experiments involved measurement of quantitative food deposits which adhered to the heating surface, composition analyses and physical properties as well as investigations of the influence of the flow rate. Milk was used particularly as a representative sample to make a comparison with other foods. From this, the conclusion indicates an index of flow rate selection to minimize the deposits, and its influence on the overall coefficient of heat transfer and pressure drop.

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Pre-commericial scale production experiments were carried out to obtain needlelike α-FeOOH fine particles.
They were produced from ferrous sulfate aqueous solution, sodium hydroxide solution and oxygen in air under higher pH than 12, using a batch-wise method.
Experiments were carried out with three kinds of particles :
a) Fe only, b) Fe plus minor Ni or Cr, and c) Fe plus minor Cr and Zn.
In all cases, the measured specific surface area of the particles was well correlated with the oxidation time, and a simple two-constant equation was proposed.
The equation is very useful for quantitative control of the specific surface area in the production of needle-like α-FeOOH particles.

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Pre-commercial scale production experiments were carried out to obtain needlelike α-FeOOH fine particles using bubble column reactors in a batch-wise method.
The distribution of the particle length along the major axis (l) and minor axis (d) were measured by transmission electron micrographs.
From the arithmetic mean length on the major axis (l_a) and that on the minor axis (da), the aspect ratio (l_a/d_a) and the coefficient of variation (σ_l/l_a) in l were calculated.
The relations between specific surface area of the particles (S_e) and l_a, l_a/ d_a, d_a and σ_l/l_a, were investigated respectively.
Further investigations were made concerning the uniformity of distribution of l graphically.

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Fluidization for plasma treatment of particles having high density such as ferrite is studied under the condition of reduced pressure. These particles are observed to be fluidized at about 100 Pa.
The relation between minimum fluidization velocity and the freeboard pressure in the fluidized bed is investigated. The minimum fluidization velocity can be correlated by the equation in which the Knudsen term is added to the viscosity term under atmospheric conditions.
The charge of ferrite can be changed by the plasma treatment of gas (such as oxygen or hydrogen) or monomer (e.g. acrylic acid). The charge can be qualitatively predicted by considering the series of frictional electrification.

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A three-dimensional, three-phase model of melting ash particles in a cokemoving bed made in previous work was applied for studying the optimal operation of a commercialized sludge-melting furnace. It has been found that the improvement of melting efficiency defined as ash/coke feed ratio depends strongly on the position of the melting zone. it is more effective to keep its position close by the region where most of the coke consumption takes place. That is to say, Operation with higher feed rates of ash and air preheating at high temperature is more effective in improving melting efficiency, but there exists a peak point of melting efficiency. Maximal melting efficiency predicted by numerical experiment was about 2.4, which was approximately 2.9 times that under standard operating conditions. Though it is difficult to confirm the higher limit of melting capacity by use of the actual furnace, it has been confirmed by the test operation that the commercial furnace under consideration can melt sludge at approximately 2.2 times higher melting efficiency than under standard operating conditions.

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Particle mixing and temperature distributions in a fluidized bed were studied in order to sustain two different temperature regions in a fluidized-bed reactor by means of a plate internal. The particle mixing rate between upper and lower regions in a fluidized bed that is divided by a perforated plate was investigated experimentally under varying conditions of gas superficial velocity and opening ratio of the perforated plate.
With the above results, a fluidized bed was scaled up to a 250-barrel/day heavy oil cracker (pilot plant reactor) where heavy oil thermal cracking and steam - iron reaction are taking place simultaneously at different temperature levels. Pilot - plant operation confirmed such temperature distributions as predicted, and also sufficient reaction results in each of two different reactions, thus supporting the validity of the system.

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Heat transfer coefficients in a pipe with heat transfer promoter are compared with those in round pipe for the same pumping power. The ratio of the heat transfer coefficient of the former to the latter is measured. Limiting Reynolds number where the above ratio of the heat transfer coefficient exceeds unity is indicated graphically as a guide for effective use of heat transfer promoters. Both twisted tape and static mixer give the highest coefficient ratios, 2.13.2, for Reynolds numbers 300550. Further, the static mixer gives high coefficient ratios, 1.8 2.1, even for especially low Reynolds numbers 150.

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Glucoamylase was immobilized on a capillary membrane by the glutaraldehyde crosslinkage method. The membrane has an asymmetric structure and contains a great number of amino groups in porous areas. Maltose was used as substrate and was forced by applying pressure to permeate through the membrane.
The amount of enzyme immobilized showed high density such as mg protein per cm² of membrane, and its specific activity was 20 % that of free enzyme. Optimum pH and temperature of enzyme were not changed by immobilization. Km and Ki values were lower than those of free enzyme when enzyme was immobilized on the membrane in low density. But, as the amount of enzyme immobilized increased, both of these values increased. In continuous operation, the activity of enzyme immobilized was stable, glucose content in permeate was more than 95% and flux decreased very slightly during 600 hours. The reaction using 30 (w/v) % maltose solution was performed by setting a short residence time in the membrane and the obtained permeate once again permeated through the immbilized membrane. Glucose content attained 96% in permeate without containing isomaltose, and in glucose content of 97.5% in permeate, isomaltose of 0.2 % was formed. This two-step reaction was effective for producing pure product because the reverse reaction was suppressed.

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Formation of organogel in lecithin/isooctane solution was effectively suppressed by the addition of a cosurfactant such as cholesterol or caprylic acid. Lecithin reverse micelles were able to form stable two-phase systems with bulk aqueous solution. In terfacial mobility of the micelles increased with concentration of cosurfactant, but the coalescence rate of the lecithin micelles was much smaller than that of AOT micelles. Water content of the organic phase, Wo (= [H₂O] / [lecithin]), was increased with decreasing the salt concentration in bulk aqueous solution in the range of W_o=10 to 20. Although extracted fractions of various proteins by the phase transfer method were less than 10 %, cholesterol oxidase was selectively extracted because of the affinity interaction with cholesterol. Cholesterol oxidase solubilized in lecithin-cholesterol reverse micelles was significantly stabilized compared with conventional AOT micelles.

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The performance of a parallel-stream HGMS filter is investigated for recovery of magnetic flocs in this experiment. To recover silicon oxide particles, which are non-magnetic, magnetic flocs consisting of silicon oxide particles and magnetite particles as magnetic seeding material are formed. Aluminum phosphate as a coagulant is added to flocculate. The time dependence of the accumulation area of magnetic flocs on a filter element is observed. At the same time, recovery is measured as a function of time. The accumulation area of magnetic flocs increases with time. Recovery is about 70% at pH7.4, but is 100% at pH5.0 with aluminum concentration of 0.02 kg · m^-3. Recovery increases slightly with increasing aluminum sulfate concentration in the range of 0.005 to 0.025kg · m^-3 at pH 7.4.
In addition, filter equations are solved numerically. The procedure of curvefitting for solutions of filter equations to experimental results are carried out and the filter performance is found to be shown by filter equations. Also, the saturation concentrations of particles accumulated in a filter are obtained.

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Dynamic UF membranes can be formed on a porous support by filtering a suspension of fine Zr particles (0.03-0.2 μm in diameter). The performance of the membrane depends on the size of the Zr particles and the thickness of the deposited layer. A flow rate below 2m · s^-1 and pressure over 0.5 MPa were sufficient conditions to deposit the particles on the support and to form a UF membrane. The optimum conditions of membrane formation were 1.0 m · s^-1 and 0.5 MPa at 25°C. The mechanism of membrane formation was analyzed by Ruth's cake filtration model. The calculated flux agreed very well with the flux of the membrane during formation under optimum conditions.

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Changes in reaction rates of Fe₃O₄ bromination and FeBr₂ hydrolysis under cyclic operation of the UT-3 thermochemical water decomposition cycle were analyzed.
The solid reactant was prepared from Fe₃O₄ powder and ZrSiO₄ powder as binder. The reaction rate equations were determined as follows for the bromination of Fe₃O₄ and hydrolysis of FeBr₂ in the 1st cycle.
bromination : r [mol · m^-3 · s^-1] =-dC_Fe3O4 / dt
= 1.5 × 10^-3C_HBr^1.5C_H2O^-0.5C_Fe3O4
hydrolysis : r [mol· m^-3 · S^-1] =-dC_FeBr2 /dt
= 0.018 C_H2OC_FeBr2^0.5
In cyclic operation, the reaction rate constants of both reactions after 20 cycles were 1.4 times as large as those for the 1st cycle. Analysis of the pore distribution showed that a large amount of reactant Fe-compound in the pellet moved from pores of around 1 μm in diameter to newly appeared pores of around 10 μm during 20 reaction cycles. The BET surface area of Fe₃O₄ after 20 cycles was about twice as large as that for the 1st cycle. It was considered that these structure changes caused the changes in the reaction rate constants.

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In this study the flow patterns of a two-phase (air-particle) swirling or nonswirling jet in the cylindrical duct were calculated by the Lagrangian and Eulerian methods. The calculated results were compared with experimental data measured by LDV. In conclusion, (1) the flow characteristics of the larger particle-laden jet were predicted successfully by the Lagrangian method, while the Eulerian method performed better for the smaller particle-laden jet; (2) the Eulerian method was apt to overpredict the particle axial velocity near the centerline of the jets and it was considered that the overprediction was caused by overpredicted value of the volume fractions of particle near the centerline.
We also studied the computational (CPU) time to obtain the converged results and the stability of calculation. The Eulerian method needed less CPU time than the Lagrangian method in calculating the smaller particle-laden jet. When the larger particle-laden jet or swirling two-phase jet were calculated by the Eulerian method, the stability of calculation became worse, and thus the CPU time increased greatly.

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The thermal stress analysis of a packed bed of coal is performed to estimate the heat and mass transfer rate in the coke oven chamber. The flow model of pyrolytic gas released from coal is included in the conventional thermal stress analysis model and the effects of gas flow on temperature and stress field within the lump coke are investigated. The flow field within the packed bed of glass beads, modeled on coke having a plastic layer and macro-crack, is observed using the visualization technique. As a result, the gas flow model is able to represent the pyrolytic gas flow within the lump coke. As the pyrolytic gas mainly flows out from the macro-crack surface rather than the heated wall side surface, the temperature difference between the crack surface and the inside of the coke becomes smaller than the conventional result. This model cannot predict the formation of micro-crack arising from the macro-crack surface since only the compressive stress is still predicted at the macro-crack surface. The model, however, suggests that simultaneous achievement of coke quality enhancement and energy-saving may be prossible by effective gas extraction in the coke-making process.

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Extraction of polyunsaturated fatty acid ethyl esters (PUFA-Et) from aqueous silver nitrate solution was studied using supercritical (SC) ethane and ethylene and the extraction behaviors were compared with those of SC-CO₂ extraction. For the SC-ethane extraction, PUFA esters were extracted faster than in SC-CO₂ extraction. The concentration change for extracted PUFA esters was similar to that of CO₂, and efficient DHA-Et separation was realized. The results of SC-ethylene extraction showed that the extraction rate was the fastest in the three kinds of supercritical fluids used and that SC-ethylene had little selectivity for the PUFA esters. This is because ethylene tends to form π-complex with Ag ion competitively.
Modeling of the semi-batch extraction process was carried out utilizing a simple mass balance relationship. All experimental extraction curves were successfully represented by this model with optimizing of apparent equilibrium constants.

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Experimental studies were conducted on the separation of fine flyash particle by use of a revised type of cyclone with movable 50% cut size. The amount of unburned carbon in the separated particle was also measured. The 50% cut size of the cyclone was changed from 0.9 to 2.3 μm by use of the vertically movable apex cone of the cyclone. When the apex angle of the apex cone was smaller, the amount of particle deposition decreased and high-efficiency particle separation was obtained.
In the case where the 50% cut size becomes less than 1 μm, the collection efficiency of the fine-particle side decreased and amount of unburned carbon increased in the fine-particle side.
The reason why the unburned carbon increased in the fine-particle side is that coarse particles were smashed in the ring nozzle disperser and fine particles having a high unburned carbon content were introduced into the cyclone.
When the 50% cut size becomes smaller, the unburned carbon amount in the coarseparticle side was nearly constant, but the value increased in the fine-particle side.The experimental data of the unburned carbon amount agreed well with the calculated results.

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Stability of liquid bridge between two discs is analyzed by a variational method. It is shown that there are two kinds of stability limit, one for constant volume and the other for constant pressure. Marginal stability limits and the perturbation functions are calculated for each condition. The shape of the perturbation function is considered to have some effect on the process of liquid bridge breakage.

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The hydrate field under the Nankai Trough having a large amount of CH₄ deposits has become the object of public attention as a potential gas resource. The possibility of exploitation of CH₄ hydrate is examined thermodynamically in likage with the environmental problem of CO₂ storage. The CO₂ supplied to the hydrate field can dissociate the CH₄ hydrate and is-finally stored there as CO₂ hydrate.

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Structural isomers o-, m-and p-nitrophenols (NPs) were separated by applying selective inclusion binding of cyclodextorin (CD) and selective permeability of ultrafiltration (UF) membrane. Three-component systems are composed of two guest molecules (NPs) and one host molecule (CD). Two-component systems are composed of one guest molecule and one host molecule. UF experiments were carried out for the two systems and the following conclusions were obtained.
1. The molecule with stronger inclusion binding in the two-component system have larger relative rejection in three-component systems.
2. This means that the separation ability in three-component systems is greater than the one calculated from two-component systems.
3. The rise ratio of rejection (η) becomes higher when pH becomes higher, but the selectivity (S_i/j) defined by η_i/η_j is nearly constant with pH or both two-and three-component systems.

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The solubilization of pyritic sulfur by Thiobacillus ferrooxidans Y5-9 was inhibited by SO₄^2- (product resulting from the solubilization process) above its concentration of 150 mol/m³. In the repeated batch culture of T. ferrooxidans Y5-9 with a membrane-type bioreactor, the SO₄^2- level in filtrate was kept less than about 150 mol/m³ by electrodialysis with SO₄^2- removal. As a result, the solubilization activity of the bacterium was maintained throughout a culture of 600 h, and the values of average sulfate fromation rate in three times-repeated batch cultures during 600 h were 0.71 (the first batch), 0.42 (the second batch) and 0.38 (the third batch) mol/ (m³·h).

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A Ni ultrafine-particle (UFP) catalyst electrodeposited on anodized porous alumina film supported on aluminum plate was prepared to provide high thermal conductivity and low pressure drop when installed in organic chemical heat-pump reactors. The effects of the electrophoresis voltage were investigated. Ni UFP deposited at a constant voltage of 140V was stable on the alumina film. The catalyst obtained was 400 times more reactive per Ni weight in acetone hydrogenation than was the Ni UFP catalyst supported on activated charcoal previously investigated. The reactivity per apparent surface area was twice as high as that of a commercial Ni catalyst supported on granular alumina.

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A simple system for measurement of resultant micromixing in a solution, in the sense of space average, has been developed. NaOH solution is injected into a solution including fluorescence pH indicator-8-hydroxy 1, 3, 6-pyrene trisulfonic acid sodium salt (HOPSA) -of which the absorbance and fluorescence spectra bands are completely different from each other. A xenon light source is focused into a light-guide fiber which is introduced to a measurement point. Fluorescence light is detected by a photomultiplier with a pin-hole section. The system was applied to local mixing measurement in the impeller stream from a disc turbine. The response curve showed violent fluctuation with reasonable time delay.

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Perfluorocarbon (PFC) droplets containing proteins were prepared by using perfluorobenzoyl chloride (PFBC) as a modifier. Two procedures for introducing proteins to PFC phase were examined. One was that proteins were directly modified with PFBC to partition the protein to PFC phase (direct method). The other was that dextran was first introduced to PFC droplets by the direct method and then proteins were immobilized through the dextran by using a NaIO₄ oxidization method (dextran-mediated method). In the direct method, there was an optimal concentration of PFBC to obtain maximal activity of the protein introduced. PFC droplets introduced concanavalin A were used for adsorption and separation of horseradish peroxidase (POD). The PFC droplets could adsorb 60% of POD added and 50% of POD adsorbed was recovered from the PFC phase. Moreover, the PFC droplets could be repeatedly used for adsorption and elution of POD.

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