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合成氨系统漏氨情况下循环水系统的处理 总被引:1,自引:0,他引:1
我公司化肥厂380#水场循环冷却水装置采用敞开式循环冷却水工艺,水质稳定剂采用全有机膦碱性水处理复合配方,浓缩倍数为3·0~3·5,pH自然稳定在8·2~9·3,杀菌灭藻剂以液氯为主,辅以氧化性和非氧化性杀菌剂交替投加。2004年1~5月,合成系统冷却器泄漏导致氨进入循环冷却水系统,给循环冷却水的控制带来严重威胁。通过在该特定条件下的各种方案的筛选应用,较好地控制了循环冷却水系统中菌藻的滋生,保证了化肥厂循环冷却水系统的稳定连续运行。1循环冷却水中微生物的危害及控制1·1循环冷却水中微生物危害循环冷却水中微生物的过量繁殖会给循环… 相似文献
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在某些循环冷却水系统中,往往由于设备的泄漏和其它原因,导致循环冷却水中含有一定量的氨,使微生物大量滋生,从而造成水质恶化,给水质稳定处理带来极大的困难,本文对循环冷却水中氨的来源;氨对循环冷却水系统的影响;漏氨循环冷却水处理技术进行了讨论。 相似文献
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针对氨汽提法尿素装置中压甲铵冷凝器管侧冷却水结垢的问题,对2套解决方案进行了比较,选用蒸汽冷凝液密闭循环冷却方案对循环冷却水系统进行了工艺优化设计. 相似文献
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S-7201(ClO2)新型杀菌剂,经试验对存在于循环冷却水系统中的异养菌、铁细菌、硫酸盐还原菌,亚硝化菌和反硝化菌等和藻类杀菌力强,药效持久,使用剂量低,不受水中pH影响,对合成氨厂漏氨时杀菌有特效。使用安全,无环保问题。 相似文献
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根据我公司循环冷却水系统1998年11月至1999年4月期间水中余氯异常的现象,和水中NO 2、NH4 含量、pH值等因素对余氯和菌藻的影响,论述了氨厂循环水加氯杀菌规律,同时强调了循环水系统运行管理的重要性。 相似文献
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浓缩倍数对循环冷却水的影响很大.浓缩倍数的控制是循环冷却水处理的关键之一.循环冷却水经过系统的热交换之后,通过冷却塔,以显热传递、蒸发传热和辐射散热的形式,把水中的热量传给空气.从而使水得到冷却重复使用.这一热量传递以蒸发传热最为主要,也就是主要在冷却塔里水份的不断蒸发而散热,但是蒸发掉的水中却不 相似文献
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Saturated very long chain fatty acids (fatty acids with greater than 22 carbon atoms; VLCFA) accumulate in peroxisomal disorders,
but there is little information on their turnover in patients. To determine the suitability of using stable isotope-labeled
VLCFA in patients with these disorders, the metabolism of 22-methyl[23,23,23-2H3]tricosanoic (iso-lignoceric) acid was studied in rats in vivo and in human skin fibroblasts in culture. The deuterated iso-VLCFA was degraded to the corresponding 16- and 18-carbon iso-fatty acids by rats in vivo and by normal human skin fibroblasts in culture, but there was little or no degradation in peroxisome-deficient (Zellweger’s
syndrome) fibroblasts, indicating that its oxidation was peroxisomal. Neither the 14-, 20-, and 22-carbon iso-fatty acids nor the corresponding odd-chain metabolites could be detected. In the rat, the organ containing most of the iso-lignoceric acid, and its breakdown products, was the liver, whereas negligible amounts were detected in the brain, suggesting
that little of the fatty acid crossed the blood-brain barrier. Our data indicate that VLCFA labeled with deuterium at the
ω-position of the carbon chain are suitable derivatives for the in vivo investigation of patients with defects in peroxisomal β-oxidation because they are metabolized by the same pathways as the
corresponding n-VLCFA. Moreover, as iso-VLCFA and their β-oxidation products are readily separated from the corresponding n-fatty acids by normal chromatographic procedures, the turnover of VLCFA can be more precisely measured.
A preliminary report of part of this work (Reference 18) was presented at the 5th International Symposium on the Synthesis
and Applications of Isotopes and Isotopically Labelled Compounds, Strasbourg, France, June 20–24, 1994. 相似文献
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为掌握佛山市顺德新城区降水中污染物的情况,2015年7月至8月,文章作者分别在雨天进行了降水取样,对降水中的pH、电导率、常见阴离子(F-、Cl~-、NO_3~(2-)、SO_4~(2-))及部分重金属(铅和镉)进行监测分析。选择有相关数据的珠江三角洲和石家庄、厦门等地的降水中污染物的情况进行对比。结果表明,顺德新城区降水中的p H和部分阴离子浓度优于珠江三角洲平均值,酸雨类型属于硫酸和硝酸混合型;其水体洁净程度略差于石家庄;铅和镉的浓度也高于厦门,甚至部分超出了人体能直接接触的安全范围。 相似文献
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H. Toda Y. Mochizuki T. Kawanishi H. Kawashima 《Nutrient Cycling in Agroecosystems》2002,63(2-3):167-173
In a coastal agricultural area in the central part of Japan (Shizuoka), we found decreasing nitrate concentration with depth in a shallow groundwater, where the depth to water table varied between 0.6 and 1.2 m below ground surface. High nitrate concentrations (5–29 mg N L–1) were often observed in the upper layer (0–2 m) of the groundwater, but the concentration decreased to less than 1 mg N L–1 in the deeper layer. Ammonium was scarcely detected, and the concentration of dissolved oxygen was usually low (< 1 mgO2 L–1) in the groundwater. Nitrate in the groundwater often had very heavy nitrogen stable isotope ratios (>20{}). There was a negative relationship between nitrogen stable isotope ratio of nitrate and its concentration. When nitrate was injected into the groundwater with acetylene and bromide (a conservative tracer), nitrate concentration decreased to 20% of the initial level within 5 days, accompanied by the increase in nitrite and nitrous oxide concentration and a little change in bromide concentration. These results indicate that microbial denitrification plays a potential role in the decrease of nitrate in shallow groundwater at the study site. 相似文献
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我国硝酸工业生产技术新进展 总被引:1,自引:0,他引:1
系统叙述了我国硝酸工业2000-2007年生产现状及主要技术成果,尤其指出了国产"四合一"机组的成功投运,使我国硝酸国产化装置取得较大的进步,表现在吨酸的铂耗、氨耗和能耗等方面接近国外引进装置水平,同时介绍了国外双加压法硝酸生产技术的进展.我国已成为硝酸生产大国,仍需以先进的技术改造和发展我国硝酸工业,确保我国硝酸工业健康有序地发展,加快从硝酸生产大国向强国迈进的步伐. 相似文献
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高效液相色谱法分析化妆品中微量成分的研究进展 总被引:1,自引:0,他引:1
综述了高效液相色谱法在化妆品中防腐剂、防晒剂中紫外线吸收剂以及性激素的检测等几个方面的应用;同时,介绍了分析所用的色谱柱、流动相、使用的检测手段以及样品的提取方法;最后针对目前存在的问题,提出了高效液相色谱用于化妆品中微量成分分析的研究方向和发展前景。 相似文献