Chemical treatment of barometric condenser cooling water systems

The application of cationic polymers to barometric condenser cooling water systems is described. Reduction of fats, oils, and greases from 900 ppm to 10 ppm in cooling water can be attained economically.     

Principles of action of polymeric flocculants

The relationship of flocculation by water-soluble polymers to the classical phenomena of colloid chemistry is pointed out and the contributions of electrostatic and non-electrostatic forces are discussed. Modern flocculants have a high degree of polymerization (e.g. c. 50 000) and an extremely extended configuration when dissolved in a favourable solvent; this factor explains qualitatively some of the peculiarities of flocculation by polymers and indicates the need for rational control of their use if optimum results are to be achieved. It is concluded, however, that a quantitative theory of specific flocculant systems is not possible at present. Future developments in flocculation technology will almost certainly include introduction of cheaper or more selective flocculants, improved control through the use of auxiliary reagents and more sophisticated consideration of the surface chemistry of materials that have to be flocculated.     

聚合铁盐絮凝剂的研究进展与发展趋势

聚合铁盐絮凝剂是一类优质高效的无机高分子絮凝剂 ,在水处理领域有良好的应用前景。综述了聚合铁盐絮凝剂的合成原理与方法、基础理论研究进展及应用情况 ,探讨了其存在的问题和发展趋势。指出聚合铁盐絮凝剂与多种阴、阳离子 ,特别是与有机高分子絮凝剂复合改性是提高效能和拓展应用领域的必然途径。     

直接空冷机组空冷凝汽器的清洗

直接空冷机组的水、汽硅含量在投运后一段时间内达不到标准,会造成汽轮机结硅垢或积硅盐,影响机组的效率.产生此问题的原因是直接空冷凝汽器冲洗质量不良.为此,提出直接空冷凝汽器冲洗的方法、步骤和技巧.     

复合高分子絮凝剂在废水处理中的应用进展

概述了4类复合型高分子絮凝剂(无机复合高分子絮凝剂、有机复合高分子絮凝剂、无机-有机复合高分子絮凝剂和复合微生物絮凝剂)及其在废水处理中的应用进展,简单比较了各类复合型高分子絮凝剂的优缺点.认为今后复合型高分子絮凝剂研发领域的发展方向为:高效、广谱、环保、价廉絮凝剂的开发;作用机理研究;以废治废理念的拓展.     

复合铝絮凝剂的制备及其脱色性能研究

以三氯化铝和有机高分子PGA为原料,制备了复合絮凝剂CPAC,并探讨了该种絮凝剂对模拟染料废水的脱色作用.研究表明,在同等铝盐投量的情况下,相对于PAC而言,CPAC脱色效率明显提高,且脱色率随PGA与铝盐的质量比(O/A)增高而上升.以活性艳红K-2BP染料为例,铝盐投加质量浓度6.8 mg/L时,PAC脱色率75.5%,CPAC(O/A=0.05)脱色率为81%,CPAC(O/A=0.1)脱色率为86%.3种染料中,CPAC对分散黄G的脱色效果最好,铝盐投加质量浓度为3.3 mg/L时脱色率达98%.     

间接空冷凝汽器喷雾降温过程分析与应用

为了适应在夏季高温环境下,间接空冷机组带较高负荷发电,可釆用喷雾降温的方法作为尖峰度夏措施。本文介绍了间接空冷机组喷雾降温过程的工作原理,分析了雾滴在空气入口处进行湿热交换的过程和影响喷雾降温效果的主要因素。以国产某单台330MW间接空冷机组为例,为其设计了一套喷雾降温系统,经使用,冷却降温效果显著。     

Solution viscosity and flocculation characteristics of linear polymeric flocculants in various media

Rheological characteristics of linear copolymers of acrylamide (AM) and acryloyloxyethyltrimethyl ammonium chloride (Q9), differing in molar mass and chemical composition, have been studied in distilled water (DW) and industrial water (IW) obtained from a paper mill. For all copolymers, the shear viscosity, μ, was much lower as the ionic strength of the water increased, with near Newtonian behaviour observed at high ionic strengths. In DW, the polymer solutions were yield pseudoplastic. Comparison of the behaviour of all flocculants at the same shear rate in the two media was accomplished by modelling the rheological data.The characteristics of the copolymers could be related with their flocculation performance in IW. The rate of flocculation in the IW was generally higher than in the DW. In general, flocculants with higher charge density were effective at lower concentrations exhibiting a lower value for the optimum PEL dosage. The flocculation data were supported with zeta potential measurements. In all cases flocs break under shear with an inability to recover the floc size with time. Overall, the polyelectrolyte behaviour in flocculation as a function of molar mass, charge density and quality of the medium could be correlated. This is of particular importance for papermaking due to the modern tendencies for water closure.     

直接空气冷凝汽器在凝气式汽轮机上的应用

介绍了直接空冷在天津石化100万t/a连续重整装置增压机汽轮机上的应用,分析了直接空冷的运行效果及存在问题,为其他石化装置应用空冷作为冷凝器提供借鉴。     

活性硅酸硫酸铝的制备及其性能研究

研究了活性硅酸硫酸铝的制备及其在污水处理中的应用,比较了不同硅铝质量比对有色金属离子的脱色率和去浊率的影响,考察了样品对某化工企业污水处理pH值的使用范围。结果表明,硅铝质量比为1∶1、pH值为4～6时,产品性能较好,且处理的污水为弱酸性或中性;产品投加量在200 mg/L时效果比较好。     

粉煤灰制备絮凝剂聚硅酸铝铁工艺条件研究

采用单因素和正交实验法对粉煤灰絮凝剂聚硅酸铝铁制备工艺进行优化研究,探讨了用Na2CO3作助溶剂时的固体原料配比、反应时间、反应温度等对粉煤灰中有效成分浸出率的影响。实验表明,最佳工艺条件为:在Na2CO3∶SiO2比为0.5时,保持温度900℃,焙烧1 h,取得初级固态产物,用30%盐酸,在100℃下搅拌浸取1 h,过滤,得到液态物质,调节pH值为1.1,Si与Al的摩尔比为1∶0.5,Si与Fe摩尔比为1∶0.3,熟化温度为60℃,可制备出粉煤灰基絮凝剂聚硅酸铝铁。     

聚合硫酸硅酸铁絮凝剂的制备方法及性能研究

用四种方法制备出硅铁比不同的聚合硫酸硅酸铁絮凝剂,通过对造纸废水的处理,比较了各种制备方法和各种不同硅铁比下产品的性能。结果显示在硅铁比为1：20时,直接向聚铁中加入试剂硅酸钠所得产品絮凝效果最好;向聚铁中加入由工业水玻璃酸性聚合而得的聚硅酸所得产品絮凝效果较好且价格较低。得到了制备聚合硫酸硅酸铁的最佳工艺条件。     

高分子絮凝剂用于造纸黑液处理的研究

探讨了造纸黑液经酸化预处理沉淀后，再用四种高分子絮凝剂进行絮凝处理，通过絮凝条件试验，优选出了最佳絮凝剂及其适宜的pH值进、药剂投量、搅拌时间、澄清时间等最传教絮凝条件，使废水中CODcr及色度达到较高的去除率。     

高分子复合絮凝剂对活性印染废水的脱色性能研究

就几种高分子复合絮凝剂对活性染料废水的脱色性能进行了研究.当聚丙烯酰胺(PAM)的阳离子度为50%时,脱色率可达到90%以上,过多的阳离子会导致胶体颗粒重新稳定;1 mg/L相对分子质量为1.2×107的PAM与150 mg/L PAC复合可达到98.2%的最佳脱色效果,分子链过长的PAM分子由于空间位阻效应使颗粒间互相排斥;1 mg/L壳聚糖(CTS)与100 mg/L PAC复合后脱色率即可大于90%,过多的CTS分子因吸附空位的饱和无法发挥作用.通过SEM观察发现在PAC单纯的电中和作用下,絮体呈较为平坦的均匀连续絮状形态.加入有机高分子絮凝剂后,由于分子链的桥联卷扫作用,呈现出不同特点的聚集形态,形成比表面很大的絮体,从而强化对颗粒的吸附和架桥作用.     

絮凝剂对水中污染物去除性能和机理的最新研究进展

综述了不同类型絮凝剂(无机、有机、微生物和复合絮凝剂)对水中常见污染物浊度、色度、重金属离子去除性能和絮凝作用机理的国内外最新研究现状,总结了目前絮凝剂去除各种污染物絮凝作用机理研究中存在的问题,分析了今后絮凝剂的研究重点,最后对絮凝剂研究的发展趋势进行了展望。     

波纹管热器及其在氨冷凝系统中的应用

介绍了波纹管换热器的强化传热机理及传热元件的轧制工艺,并与光管换热器的换热性能进行了比较,及在氨冷凝系统中的应用情况。     

开式冷却循环水系统冷凝器化学清洗中“赤水”现象的处理

分析了冷凝管外露式冷却循环水系统化学清洗造成"赤水"的现象。采用多聚磷酸钠和亚硝酸钠进行钝化处理,其钝化剂用量小、钝化时间短、钝化效果好。     

3种天然高分子絮凝剂对浊度去除效果的比较研究

以山药、仙人掌和芦荟作为絮凝剂,研究并比较了这3种天然高分子絮凝剂对高岭土模拟水样的絮凝效果。通过单因素实验,研究了3种天然高分子絮凝剂在不同初始pH、絮凝剂投加量和静置时间下对浊度的去除效果,优化絮凝条件。通过在模拟水样中加入不同质量浓度的无机盐,考察了无机盐浓度对3种絮凝剂絮凝效果的影响。结果表明,3种絮凝剂均表现出良好的絮凝性能。在优化条件下,山药对浊度的去除效果最好,可以将浊度降至16.95 NTU。其次是仙人掌和芦荟,絮凝后的浊度可分别降至30.58 NTU和33.50 NTU。在实验条件下,无机盐浓度对絮凝效果的影响不大。     

Investigation of mixed polymeric liquid-crystal systems

Conclusions The temperature regions of fusion and viscosity of mixed liquid-crystals based on PPTA have been investigated.On appropriate selection of the copolymers, mixtures of polymers, or mixed solvents, it is possible to vary the temperature of transition of these systems from the solid state to the liquid one over a wide range.Translated from Khimicheskie Volokna, No. 3, pp. 19–21, May–June, 1983.