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Volume 23 (1969 - 197･･･
- Issue 6 Pages 246-
- Issue 5 Pages 181-
- Issue 4 Pages 129-
- Issue 3 Pages 81-
- Issue 2 Pages 46-
- Issue 1 Pages 3-
Volume 23, Issue 4
Displaying 1-5 of 5 articles from this issue
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Ichiro HAYANO, Takashi UCHIDA1970 Volume 23 Issue 4 Pages 129-133
Published: 1970
Released on J-STAGE: February 19, 2013
JOURNAL FREE ACCESSA series of studies on the hydrate formation equilibria in the C3 and C4 hydrocarbons and water systems have been finished by the completion of this study.
In this study, hydrate formation equilibria were examined on the propane, isobutane and water system, and the P-T diagram was experimentally determined in connection with the mixing ratio.
The two component hydrocarbons in this system are featured by the fact that each of them is capable of forming solid hydrates by itself. Accordingly, the experimental results indicated that the previously proposed theory was not applicable.
Also, a supplementary work was conducted to mathematically formulate the condensation line, the formation line, and the freezing line in the P-T diagram for each of those two component hydrocarbons or their hydrates.View full abstractDownload PDF (10331K) -
Studies on the Electrodialytic Equipment with Ion Exchange Membrane (X VIII)Shoni AZECHI, Yoshie FUJIMOTO1970 Volume 23 Issue 4 Pages 134-147
Published: 1970
Released on J-STAGE: February 19, 2013
JOURNAL FREE ACCESSThe flow characteristics of the practical-scale electrodialytic apparatus of filter-press type possessing 301 pairs of membrane cells with an effective membrane area of 113 dm2 were examined under operation for sea water concentration at the current density of 3A/dm2.
The results obtained were as follows:
1. The hydrostatic pressure drop in membrane cell (ΔH) was found to increase in proportion to the 1.3-1.26 power of amount of flow (Q).
2. Among the three feeding systems tested (A, B and C), the C system showed the smallest variation of flow rate (u) in diluting compartment and the B system showed the largest.
In case of the A system which is usually used for practical apparatus, the ratio of Umax to Umin ranged from 1.2 to 1.6.
3. The effect of equalizing conduit, which was designed to decrease the changes of hydrostatic pressure Ha and Hb in the internal conduit of dialysate and to improve the distribution of flow rate in the diluting compartment, was found to be small.
4. The voltage of the cell block decreased in proportion to about the -0.07--0.11 power of U.
5. The hydrostatic pressure drop in the membrane cell (ΔH) was discussed.
6. The distribution of the flow rate (ν) in the internal conduit of dialysate was obtained from the distribution of U.
It was found that variations of Ha and Hb became large in the part of the conduit where ν exceeded about 30 cm/sec.
7. The relations between the hydrostatic pressure difference (Δha) in the internal conduit and Ha, and between Δhb and Hb were also discussed.View full abstractDownload PDF (28969K) -
Noboru OGATA, Nobuko INOUE1970 Volume 23 Issue 4 Pages 148-153
Published: 1970
Released on J-STAGE: February 19, 2013
JOURNAL FREE ACCESSAn isotope dilution method has so far been used for accurate determination of uranium contained in sea water, but this method necessitates a special room for using uranium isotope. In this paper, a study was made to improve the separation method and fluorophotometric method for the determination of uranium in sea water without using the isotope dilution method.
The separation of uranium in sea water was carried out under the foliwing procedure. Ten micro-grams of uranium was added to 4 liters of sea water sample, and the sample solution was warmed at about 80°C. Uranium in the sample was adsorbed into titanic acid which was prepared by homogeneous precipitation method using urea. The uranium adsorbed into titanic acid was extracted with mixture of sodium carbonate and sodium hydrogen carbonate at 100°C. The extracted solution was passed through in anion exchange resin of carbonate type, and the uranium adsorbed into the resin was eluted with hydrochloric acid solution. The recovery of uranium by this method represented 90%, which was higher than the conventional methods but was still incomplete. Therefore, the condition of adsorption must be kept stable to obtain the recovery with small variation, and the determinated value was corrected with the recovery.
A given amount of this pretreated solution was pipetted into a plutinum dish, dried, and melted at 665°C with carbonate-sodium fluoride flux, and the fluorescence strength of the dish was measured. The error caused by the variation of melting condition could be decreased by using a furnace with a fan and correction by simultanious operation with the uranium standard solution.
The unevenness of the fluorescence strength in the dish could be decreased by using the temporary standard and rotating the fused dish during the measurement, and the measuring error was below 2%. Uranium content in sea water collected along the coast of Odawara showed 3.34μg/l by this method.View full abstractDownload PDF (14450K) -
Studies on Mother Liquid in Salt-Manufacturing Process (Part 13)Tsutomu MASUZAWA1970 Volume 23 Issue 4 Pages 154-162
Published: 1970
Released on J-STAGE: February 19, 2013
JOURNAL FREE ACCESSIn this paper, the author carried out a study to examine the crystallization of the brine produced in the salt-field of Ako (W) Salt Manufacturing Factory when it was concentrated in the crystallizer of the factory. The purpose of this study was to examine the quality of salt-field brine (WS, June 1966), ion-exchange membrane brine (WI, January 1968) and their mixture (WM, October 1967) and to make a comparison on the alteration of their chemical composition in case they were crystallized in the same vacuum evaporation system plant.
Also, the high caking tendency of the salt manufactured at the W factory in 1964-65 were examined, and the following results were obtained:
1. Mother liquid in the crystallizer of this factory was in the range of concentrating process between a1 and a2 where the liquid was saturated with sodium chloride only, or it was in the range over a2 where the liquid was saturated with sodium chloride and magnesium sulfate or its double salt.
2. Differing from those observed in other factories, the concentrating process of the brine in the crystallizer of this factory showed a tendency of containing more sulfate ion than the concentrating process of sea water.
3. The precipitates of the mother liquid were composed of sodium chloride, calcium sulfate and a little amount of glauberite in the early stage of concentrating process, and in the late stage they were composed of sodium chloride, polyhalite (K2SO4·MgSO4·2CaSO4·2H2O) and magnesium sulfate.
4. The high caking tendency was attributed to the high purity of salt, and the small size of particles and the high content of sulfate ion.View full abstractDownload PDF (18673K) -
Studies on Mother Liquid in Salt-Manufacturing Process (Part 14)Tsutomu MASUZAWA, Tetsuo MATSUO, Nobuyoshi TENJIN1970 Volume 23 Issue 4 Pages 162-173
Published: 1970
Released on J-STAGE: February 19, 2013
JOURNAL FREE ACCESSThe authors studied the running data, the chemical composition at the saturation point with potassium chloride and the potassium content of the produced salt when ion exchange membrane brine was tentatively crystallized in the third effect pan of the vacuum evaporation system in Ako Salt Manufacturing Factory. The results obtained from the above-mentioned study were as follows:
1. During its crystallizing process in the third effect pan of the triple effect evaporator for 56 hours, the deposition of scales to the heating tube, salting-up to the wall of the pan, which was especially of a big problem, and any other troubles did not occur at all.
2. During its concentration at 50°C, potassium chloride began to crystallize into nearly the expected composition; density dt4= 1.255, magnesium chloride 13.5 per cent and potassium chloride 7.5 per cent.
3. Potassium chloride in the produced salt of common grade was removed by industrial washing to the extent of 0.17 per cent, as compared with 0.05 per cent of salt produced from salt field brine and 0.08 per cent of salt produced from the mixture of salt field and ion exchange membrane brines.
4. The ion exchange membrane brine began to saturate with calcium sulfate before sodium chloride, and it soon became fine crystals and suspended in the pan.
5. A comparison of saturation points (a1 saturated with sodium chloride and a2 saturated with potassium chloride) was made between the value calculated from the equilibrium and the one observed from the figures. As the result, the calculated value coincided with the observed one for a1, but it did not coincide for a2.View full abstractDownload PDF (27101K)
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