Vapor pressures of liquids increase in the presence of excess high pressure gases. Recent papers on the phase behaviors of high pressure hydrogen and pure hydrocarbon systems were thoroughly investigated and it has been found that within the range of y<0.2, x>0.8 and T_r<0.9, in other words in case when the assumptions of ideal gas and ideal solution are reasonably valid, the Poynting equation¹⁾ may be used to estimate the vapor pressure of the liquid under high pressure, P_π.
Here x and y are the mole fraction of hydrocarbon in the liquid phase and in the gas phase respectively, and T_r is the reduced temperature of hydrocarbon concerned. The new method of calculation of flash vaporization of petroleum oil in the presence of high pressure hydrogen has been developed.
Supposing that sp. gr. and A.S.T.M. distillation data are available,
1. At the first true boiling point curve of the sample oil is calculated by Edmister's method.
2. Using the normal boiling points and ρ/ω of the paraffin homologous members, the contents of the representative components are estimated.
3. The average molecular volume of each component under pressures between total pressure π and normal vapor pressure P_n is calculated by Watson's method, using the density ρ and expansion factor ω of each component.
4. The value of P_π/P_n of each component is calculated by Poynting equation.¹⁾
5. Solubility of hydrogen in the given sample oil under the given total pressure and at the given temp. is estimated from the literature.
6. Equilibrium flash vaporization constant of each component K_i under given conditions is calculated by the following equation.
(9)
Here, n₀ is the mole fraction of oil in the liquid phase and can be calculated from the solubility data, and P₀ is the partial pressure of the oil vapor in the vapor phase.
7. Dry points and percentages of vaporization at various temp. can be calculated by equations (11), (12) and (13) (by trial and error method).
8. The results of calculation were plotted in Cox vapor pressure charts and vaporization line charts; Fig. 5 and 6 thus obtained serve well to explain the actual operation of the high pressure hydrogenation plant.
The authors believe that this method of calculation may find wide practical applications in the various high pressure vaporization processes.

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The discharge coefficient of orifice meter in a commercial 1/2" gas pipe for plastic fluid was calculated and C vs. Re diagrams were drawn.
The concentrations of sludge tested were 4.1, 10.8, 15.0, 17.5, 23.1, 26.6, 31.2, in wt. % and the ratios of the orifice areas to the sectional area of the pipe were 0.096, 0.247, 0.348, 0.467, 0.652.
The results of the experiments were as follows:
(1) The limits of the concentration for measurable flow rates are,
m=0.247, up to 31wt.% or more. m=0.467, up to 26wt.%
m=0.348, up to 31wt.% m=0.652, up to 17wt.%
(2) The drag coefficient C increases rapidly when Reynolds number Re is less than 10⁴, and after having reached maximum value, it decreases as Re decreases.
The more the value of m becomes the greater is the value of C_max., and tbe steeper is the slope of the curve.
(3) The more the concentration of sludge becomes the smaller is the value of Re at the point where C reaches maximum.
(4) When m is constant, C approaches a constant regardless of concentrations of sludge within the range for Re>2×10⁴.

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The rate of the exchange of oxygen atoms between gaseous oxygen and water vapor was examined under various conditions ranging between 487-598°C of temperature and 30.1-136.1cc/sec of feed rate. Cylindrical pellets of height and diameter each equal to 0.2cm were prepared from the mixture of 1:3 of chromic oxide and the Naegi kaolin, and packed in a silica tube of 1.6cm inside diameter by 23.5-24.0cm height. Random dense arrangement of the bed was measured by the pressure drop of the gas flowing through the tube.
The relations between the logarithms of the total exchange reaction rate R and the reciprocal of the temperature T in °K are plotted in the Fig. 3. These plots are for convenience sake, divided into two classes, one belonging to the lower feed rate less than 48cc/sec and the other to the higher feed rate above 64cc/sec. The values of R in these two classes differ by the factor of about 1.3 at lower temperature and 1.6 at higher temperature. These differences are explained by the effects of mass-transfer of the gas film, of longitudinal diffusion of reactants and products, and of the pressure drop through the bed. Mass transfer resistance of the gas film is less than 3% of the overall reaction resistance under the restricted conditions of the experiments. Longitudinal diffusion may contribute a higher percent.
These results are compared with the rate of exchange between hydrogen and deuterium measured by Holm and Blue. The effect of space velocity of the reacting gases on the rate of the exchange is more remarkable than that observed above.

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[in Japanese]

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