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Volume 28 (1974 - 197･･･
- Issue 6 Pages 379-
- Issue 5 Pages 321-
- Issue 4 Pages 196-
- Issue 3 Pages 146-
- Issue 2 Pages 85-
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Volume 28, Issue 5
Displaying 1-6 of 6 articles from this issue
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Polluting Materials in Sea-water and Sea-water Distillation Process (Part2)Tetsuo YARISAWA, Toshikatsu HAKUTA, Teiji OKUBO, Kazuo SHIMIZU1975 Volume 28 Issue 5 Pages 321-326
Published: 1975
Released on J-STAGE: February 19, 2013
JOURNAL FREE ACCESSIn seawater distillation plants, phenolic substances in seawater seem to be evaporated and concentrated into the product water. The behavior of phenol and its derivatives in this process was examined by using a 3,000 m3/day multistage flash evaporator and a laboratory-scale distillation apparatus. Phenol,o-and m-cresols, and thymol were added to the make-up line of the evaporator, and their distribution in the plant was traced (Table-1 and Figs.-1-4). The greater portions (70-90%) of the added materials proved to be evaporated and concentrated into the product water in the following order: -phenol<m-cresol<o-cresol<thymol. Concentrations of these materials in the product water were about 1.5-2.0 times as large as those in the make-up line. The flask test proved that the distilling amount of these four phenolic substances was to be in the same order as in the plant test. It also showed that the distilling amount was not affected by the pH of the charged liquid but was affected by its brine concentration or salinity (Figs.-5-10).View full abstractDownload PDF (3426K) -
Masao MOTOYAMA, Minoru KADOTA, Shumpei OKA1975 Volume 28 Issue 5 Pages 327-333
Published: 1975
Released on J-STAGE: February 19, 2013
JOURNAL FREE ACCESSThe solubilities of the quinary system of NaCl-KCl-MgCl2-CaCl2-H2O and its surrounding systems at 0°C were investigated to get the basic data for the graphical computation of the treatment process for recovering valuable components in the ion exchange membrane brine and its bittern. The results obtained were as follows:
1. Four salts were precipitated lrom the quaternary eyetem of NaCl-KCl-MgCl9-H9O9i.e., Na CI, KCl, MgCl2·6H2O and carnallite (MgC12·EKCl·6H2O), and the KC1 crystallization region in the diagram on the triangular coordinate (g/100 g salts) was found to occupy 68.9% of the total area, while that of the NaC1 was 30.5%.
2. Three salts were precipitated from the quaternary system of NaCl-MgCl2-CaCl2-H2O,i.e., NaCl, MgCl2·6H2O and CaCl2·6H2O, and the area occupied by the NaCl was 99.1%.
3. Five salts were precipitated from the quinary system,i.e., NaCl, KCl, MgCl2·6H2O, CaCl2·6H2O and carnallite, and the area occupied by the simultaneous crystallization region of KCI and NaCl in the diagram (g/100 g (KCl+MgCl+CaCl)) was 86.8%, while that by the carnallite and NaCl was 10.8%.View full abstractDownload PDF (4357K) -
Application to Fluorilnetric Determination of Uranium in Sea WaterShiro GOHDA1975 Volume 28 Issue 5 Pages 334-341
Published: 1975
Released on J-STAGE: February 19, 2013
JOURNAL FREE ACCESSMicro amount of uranium was determined by fluorimetric method using alkali carbonate fluoride fusion. The effect of various alkali carbonate fusing fluxes on the fluorescence intensity were investigated. The recommended procedure was as follows. One ml of sample solution was gently evaporated in a 10ml platinum crucible. To the dried residue, 1.00g of fusing flux (NaF-Na2CO3-K2CO3 1: 4.5: 4.5 or NaF-Na2CO3-K2CO3-LiF 3: 3.5: 3.5: 0.2) was added and the mixture was fused for a desired period (20 min) in an electric furnace kept at a required temperature (600-690°C). After fusing the bead was crushed to fine powder, packed in a sample dish (3 mm depth×17 mm in diameter) for fluorescence measurement, and then fixed with a quartz plate (1mm thick), to obtain a flat surface. The sample was excited with mercury line at 365nm and fluorescence intensity was measured at 558nm, using a uranine solution as the reference standard. By the present procedure, more than 0.005μg of uranium in 1g of flux could be determined within the error of ±1%. The procedure was applied to the determination of uranium in sea water, after uranium was separated and concentrated by the solvent extraction as uranyl oxinate. The uranium content in sea water was estimated to be 3.16±0.04 μgU/liter.View full abstractDownload PDF (5680K) -
Polluting Materials in Sea-water and Sea-water Distillation Process (Part 3)Tetsuo YARISAWA, Teiji OKUBO, Hideo TOGANO1975 Volume 28 Issue 5 Pages 342-346
Published: 1975
Released on J-STAGE: February 19, 2013
JOURNAL FREE ACCESSIn the first report of this paper, we confirmed that ammonium ion (NH4+) was concentrated into the product water if the seawater distillation was carried out by using the seawater polluted with ammonia. Besides this evil influence, the existence of NH4+in seawater was supposed to accelerate the corrosion of the plant and the dissolution of the metallic constituent materials into the product water. By adding ammonium chloride to the make-up line of a 3,000 m3/day multistage flash evaporator, we examined the change in time of the metallic ion concentrations in the product water and in the effluent brine of the plant (Figs.-1, 2 and 8).
Iron, copper, and zinc ion concentrations in the product water decreased with an increase in NH4+concentration when NH4+concentration was comparatively small (Fig.-1). This might be due to a decrease in the corrosive power of the product water caused by its pH elevation. When NH4+ concentration increased more, the concentration of copper ion distinctly increased; total ion concentration continued to decrease; and the data of zinc ion became to show much fluctuation (Fig.-2). These data were analyzed by plotting them against the pH and NH4+ concentration (Figs.-4-8).
Iron and copper ion concentrations in the effluent brine increased in line with an increase in the concentration of NH4+ (Fig.-9). Main reason for this increase was supposed to be the lowering of the pH value of the circulating brine, but the phenomenon was too complicated to do a precise analysis.View full abstractDownload PDF (3214K) -
Masao MOTOYAMA, Minoru KADOTA, Shumpei OKA1975 Volume 28 Issue 5 Pages 347-352
Published: 1975
Released on J-STAGE: February 19, 2013
JOURNAL FREE ACCESSFor estimating the solubility of salts in the quinary system saturated with sodium chloride within the temperature range of 0°C to 100°C, approximation equations were derived from the data on the solubility of sodium chloride in the ternary systems. Also, the authors tried to verify the validity of the equations by experiments, and concluded as follows:
1. The calculated values for potassium chloride, magnesium chloride and calcium chloride of the quinary system were found to coincide with the experimental values within the errors at ±0.05 weight per cent.
2. As a general rule, the errors of the calculated values for sodium chloride became larger if the value of n was larger, but the relative differences were within±4.5 per cent in the case of n<0.25 25 moles/100g solution.
3. It was inferred that the change of the compositions of the solutions by evaporation of the ion exchange membrane brine in the concentration range in which only sodium chloride crystal precipitate could be estimated from the equations.View full abstractDownload PDF (4614K) -
Vapor-Liquid Equilibrium of Polluting Materials in Seawater (part 1)Toshikatsu HAKUTA1975 Volume 28 Issue 5 Pages 353-359
Published: 1975
Released on J-STAGE: February 19, 2013
JOURNAL FREE ACCESSIt is very important to investigate the behavior of volatile polluting materials in an MSF desalination plant when the product water from seawater is used. In this work, the vapor-liquid equilibria of ammonia-water system were measured at some pH values, salinities and pressures by using Othmer type of equilibrium distillation apparatus.
The variation of pH in these experimental parameters had the largest influence upon the vaporliquid equilibrium ratio (K=y/x) of this system. Ammonia was considerably concentrated into vapor phase at pH 8 and above, but it was hardly concentrated below pH 6. The K-values of ammonia-water system incresed as the system pressures were higher. On the other hand, the Kvalues decreased as the salinities of aqueous solutions increased.
The tendency obtained by simple batch distillation of ammonia-water system agreed well with the tendency in case of equilibria of the same system.View full abstractDownload PDF (4582K)
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