The moisture movement in drying clay may be expressed by the following equation:∂c/∂=∂(D∂c/∂x)/∂x
where c is moisture concentration, t drying time, χ distance in which moisture moves through clay and Dmoisture diffusion coefficient that varies with the internal moisture concentration.
By using the experimental values of the moisture diffusion coefficients on several kinds of clay, including Kibushi clay, Gairome clay and mixture of either of these with feldspar, as well as stone-ware clay, the above non-linear differential equation was solved. As a result of the analysis, the moisture distribution in drying clay could be formularized.
The validity of this treatment was attested by ascertaining the favorably good agreements between the calculated values and the experimental data concerning the moisture distribution in the above clay during a drying process.

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Some systematic treatments are proposed on typical flow models, force balance and fluid friction in gas-liquid mixed phase flow through vertical pipe.
Various flow patterns which appear in mixed-phase flow may be classified into two typical flow models of bubbling flow and annular flow with liquid entrainment.
Force balance in fluids shows that, neglecting the effect of acceleration, pressure drop is contributed by two forces of wall friction and the effects of gravity on the fluids, and the relation is given by Eq.(15).
The investigations on liquid hold-up and wall friction become essential for the systematic development of flow phenomena.
Wall friction is examined in terms of “two-phase friction factor” by Eq.(18), based on experimental data.
For the range of high gas rate and high liquid rate, the “two-phase friction factor” is found to be correlated a curved line by liquid Reynolds number with ±30% deviation, as shown in Fig. 6, and the correlation curve is compared with that of single phase flow through smooth pipe.
The correlation curve indicates that there are two basic flow mechanisms of pseudo-stream line and turbu-lent flow in mixed-phase flow, and the transition to turbulent flow occurs gradually along this curve.

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This paper presents the analytical treatment and the correlation procedure on “two-phase friction factor”in vertical upward mixed phase flow.
From previous results, shear distribution in annular liquid layer is given by Eq.(6) in terms of wall shear stress and liquid hold-up.
Velocity profile in the liquid layer may be assumed to have two regions of laminar sublayer and turbulent surface layer, as shown in Fig. 1.
Employing Eqs.(8) and (10) for the velocity distribution in these layers, the theoretical relation between“two-phase friction factor” fT. P. and its effective factors is as shown by Eq.(21), with the dimensionless groups of liquid Reynolds Number dL/μ_L, hold-up parameter φ, the factors of entrainment fraction L/Lf and φ/φf and the relative thickness of laminar sublaver c.
A number of data obtained by the author and other investigators were examined based on Eq.(21) for the ranges of dL/μ_L; 2 to 18000, pipe diameter d; 10 to 35mm i. d. and liquid viscosity μ_L; 1 to 44c. p.
The results were as follows;
For the range of pseudo-stream line flow (Re_L<1, 000), the friction factor fT.P. may be substantially correlated by dL/μ_L and φ. The correlation diagram of fT. P.-Re_L-φRe_L, is given in Fig. 2.
For the range of turbulent flow (Re_L>1, 000), fT. P. may be practically correlated by dL/μ_L as shown in Fig. 5, and Eq.(39) may be applicable with ±30% deviation, furthermore the effects of entrainment fraction were discussed.

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Eighteen years ago, Fagerholt showed that particle size (a′) of sieving residue obtained in time t, is deter-mined as the average particle size of the fraction in continued sieving under same conditions up to time 3t.
Extending the above statement, a new method of calibrating the sieve and representing the sieve analysis has been developed.
In order to represent the sieve analysis, the sieving of glass spheres, with equivalent sphere diameter (D), were used for the particle boundary, Eq.(14)(instead of cube roots of particle volume (a′) by Fagerholt).
Plotting the cumulative per cent on sieve (R), against the particle boundary (D) on the log-probability scale gave one line, i. e., particle size characteristic line, irrespective of the sets of sieve, Figs. 2-4, while the same sieve, irrespective of sample, gave another line, i. e., the effective opening line, Eq.(15).
Experimental data gives the value of σ_g=1.012 (const.). For materials which differ in particle spheres, D₅₀ for same sieves gives different values, but σ_g remaines constant. For glass spheres, D_50(g) is approximately equal to the opening of sieve a.
Fig. 9 shows a chart of effective opening lines for a set of sieves of the standard screen. Fig. 10 illustrates the method of estimation of sieve analysis by one set of sieves from the analysis by another set of sieves.
Table 5 shows the table of effective opening of silk bolting cloth compared with the value of opening by Haltmeier.

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Vapor-liquid equilibrium data at atmospheric pressure were obtained for the methanol-water system containing sodium chloride, calcium chloride, or aluminium chloride of various concentrations and for the water-acetic acid system containing sodium chloride, sodium nitrate, or magnesium chloride of various concentrations.
The water-acetic acid system containing sodium chloride has an azeotrope above a certain concentration of the salt, and the composition becomes richer in acetic acid with increasing salt concentrations.
The relative volatility of the water-acetic acid system reverses its trend, that is, acetic acid becomes more volatile than water by the addition of magnesium chloride above a certain concentration.
For the representation of the salt effect a simple empirical equation is proposed, which correlates the data for the water-acetic acid system very well but does not fit the data for the methanol-water system. The data for the latter system can be correlated by the equation proposed by Johnson et al.

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Krystal-Oslo type crystallizer on a pilot plant scale equipped with the evaporating heater was used to make ammonium sulfate crystals.
The operational characteristics were found from the performance data.
1. When the total crystal-bed was recycled in the state of suspension, violent formation of nuclei took place after heating, and the crystals from the bottom of suspension container were of poor growth and small diameter.
2. So long as the upward flow-velocity was controlled properly, the crystallization together with its classification was possible and approximately uniform crystals of larger diameter were easily obtained.
3. When the product particles are required to have a given length of diameter, the upward flow velocity, or the circulating flow rate cannot be varied arbitrarily. Increasing capacity is attainable by increasing the degree of supersaturation, but the preferable form of crystals can not be obtained beyond certain limits.
This pilot plant was operated most satisfactorily at the capacity of 0.4 [t/D].
4. Krystal-Oslo type crystallizer should be operated in the severely controlled range of V₀, W and S.

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Collection of carbonaceous material generated by partial oxidation of gas oil was carried out with scrubber and venturi scrubber, and the performances of these equipment were studied. The result was that both the scrubber and the venturi scrubber could not exhibit satisfactory performance, but it was concluded that this type of process could be applied to the collection of carbonaceous material of high loading after improving their design and selecting proper operating conditions.

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