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21.
分析了青岛海晶化工集团有限公司由于淡盐水脱氯系统中的部分氯气溶解造成后续工序中Na2 SO3用量加大等问题。改造后Na2 SO3 的用量由原来的 12kt/ (t·NaOH)降低到 6kg/ (t·NaOH) ,降低了生产成本 ,提高了经济效益 相似文献
22.
根椐已有的文献与数据,采用数学模型方法,研究了硝酸钠卤水沸点在不同组成、不同压力条件下的变化关系,确定了硝酸钠卤水沸点与质量分数及压力的数学方程式;根椐硝酸钠卤水压力与组成,可以计算出硝酸钠卤水的沸点值,为新疆都善县库木塔格硝酸钠矿大规模生产硝酸钠提供了重要设计依据. 相似文献
23.
24.
浅谈一次盐水的工艺指标控制 总被引:2,自引:0,他引:2
介绍了一次盐水的各项工艺指标对生产的影响以及稳定控制这些指标的方法,强调了在生产中控制好一次盐水的工艺指标是影响产品质量及离子交换膜使用寿命的关键。 相似文献
25.
Jose Gerde Connie Hardy Walter Fehr Pamela J. White 《Journal of the American Oil Chemists' Society》2007,84(6):557-563
Two extruded-expelled physically refined soybean oils with reduced contents of linolenic acid, ultra-low- linolenic acid (ULL,
1.5%) and low-linolenic acid (LL, 2.6%), and a extruded-expelled physically refined control oil (control, 5.3% linolenic acid)
were evaluated by frying French fries in a commercial-like setting for 6 h day−1 during 23 days. The oils became darker, increased in yellow color at the beginning, and became redder and less green throughout
the process. Free fatty acids levels were not different among the oils until day 14, after which, ULL was different from the
control for the remainder of frying. The conjugated dienoic acid values were greatest in the control. Generally, ULL and LL
oils had lower percentages of polar compounds than did the control, providing a frying life 2 days longer than the control
and ~30% increase in frying time. A trained sensory panel evaluated the French fries on days 2, 5, and 6. Buttery and potato
flavors decreased, and rancid and painty flavors increased over frying time for all products. Rancid flavor was highest in
the fries from the control oil. Overall, the ULL and LL oils performed better than did the control oil and ULL tended to perform
better than the LL. 相似文献
26.
Rana M. Tubaileh Antonio Garrido-Fernández M. Victoria Ruiz-Méndez Manuel León-Camacho Enrique Graciani-Constante 《Journal of the American Oil Chemists' Society》2002,79(1):101-104
Changes in the contents of waxes and fatty alcohols during deodorization/physical refining of bleached olive oil were studied.
Experiments were carried out with 1.85% acidity oil, which was physically refined in a discontinuous deodorizer of 250-kg
maximum capacity using nitrogen as stripping gas instead of steam. The variables studied were load and temperature of oil
in the deodorizer as well as N2 flow. Analyses of waxes and alcohols were carried out at different operation times. The maximum content of wax was always
observed when the oil reached the deodorization temperature. The variation in the wax content depended on temperature and
N2 flow. Wax decomposition started and continued during the operating time, and a progressive decrease, which was pronounced
between 3 and 4 h, was observed. Small changes in waxes were observed between 4 and 5 h. Total content of fatty alcohols diminished
throughout the operating time, and changes did not depend on the variables studied. 相似文献
27.
28.
P. J. Wan R. J. Hron Sr. M. K. Dowd M. S. Kuk E. J. Conkerton 《Journal of the American Oil Chemists' Society》1995,72(6):661-664
Hexane has been used for decades to extract oil from cottonseed and is still the solvent of choice for the edible-oil industry.
Due to increased regulations as a result of the 1990 Clean Air Act and potential health risks, the edible-oil extraction industry
urgently needs an alternate hydrocarbon solvent to replace hexane. Based on laboratory-scale extraction tests, two hydrocarbon
solvents, heptane and isohexane, were recommended as potential replacements for hexane. A cottonseed processing mill with
a 270 MT/day (300 tons/day) capacity agreed to test both solvents with their expander-solvent process. Extraction efficiencies
of isohexane and heptane, judged by extraction time and residual oil in meal, refined and bleached color of miscella refined
oil, and solvent loss, were comparable to that of hexane. However, fewer problems were encountered with the lower-boiling
isohexane than with the higher-boiling heptane. With isohexane, the daily throughput increased more than 20%, and natural
gas consumption decreased more than 40% as compared to hexane. 相似文献
29.
30.
The galvanostatic technique on a laboratory scale has been shown to be a useful tool in detecting the presence of nodules on the cathode during copper electrodeposition by using the value of the starting electrolytic potential and by the presence of a cathodic polarization peak on the potential–time curve. Studying the morphology of the deposit with a scanning electron microscope at various magnifications confirmed the galvanostatic results. It is postulated that inappropriate concentrations and/or ratios of the additives (thiourea, gelatin and chloride ions) are associated with a certain current density that generates intergranular microcracks due to adsorption of the additives and leads to the formation of nodules at the macroscale. 相似文献