合成氨系统漏氨情况下循环水系统的处理

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…     

工业循环冷却水水质分析方法(部标暂行)(连载)

10.氨和铵离子测定方法甲、氨气敏电极法本方法适用于测定循环冷却水和天然水中的氨和铵离子,其含量为每升含1—1000毫克铵离子。氨气敏电极由pH 玻璃电极、饱和甘汞电极、内     

漏氨循环冷却水处理技术探讨

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。     

循环冷却水浓缩倍数的检测及控制

敞开式循环冷却水系统在运行过程中由于水分蒸发，水中盐离子含量越来越高，为了维持水中含盐量在一定浓度必须补充新鲜水加以稀释，并排出浓缩水。操作中通常通过控制浓缩倍数来控制水中盐的浓度。循环冷却水的浓缩倍数越高，某些盐离子含量就越高（如Cl^-），对设备的危害就越大；相反，浓缩倍数太低就要增加补水量，又很不经济。可见，合理地确定循环冷却水的浓缩倍数是非常重要的。     

循环冷却水微生物调节水质机理研究进展

微生物调节水质(WQCM)方法是将特定微生物菌剂加入循环冷却水中,利用多种功能菌新陈代谢的协同作用调节循环冷却水水质的一种新颖的循环冷却水处理方法,目前正处于深入研究和初步应用阶段.循环冷却水WQCM方法的关键是阐明微生物功能菌调节循环冷却水水质的作用机理及协同机制.介绍了目前循环冷却水WQCM的应用现状;归纳了WQCM防垢、防腐、防生物黏泥以及浓排水降污的作用机理;指出了当前WQCM机理研究存在的问题,展望了WQCM方法未来的研究方向和应用前景.     

氨对循环水的影响

在合成氨厂循环冷却水系统中常泄漏一定量的氨,氨的含量达几十到上百μg/g。循环冷却水中含氨属不正常,而且是不易克服的问题,这就给循环冷却水利用带来严重的影响。1 氨对循环冷却水的影响     

氨汽提法尿素装置中压甲铵冷凝器防结垢工艺优化

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.     

S—7201（ClO2）在工业循环冷却水上的应用

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。     

关于氨厂循环水加氯杀菌规律的探索

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。     

浓缩倍数对循环冷却水的影响

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     

佛山市顺德新城区降水中污染物的监测和分析

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。     

Metabolism of trideuterated iso-lignoceric acid in rats in Vivo and in human fibroblasts in culture

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.     

高效液相色谱法分析化妆品中微量成分的研究进展

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。     

Denitrification in shallow groundwater in a coastal agricultural area in Japan

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.     

我国硝酸工业生产技术新进展

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.