聚醚改性有机硅消泡剂的制备及性能评价

发布时间：2018-06-29 02:43

  本文选题：有机硅消泡剂 + 聚醚改性有机硅　； 参考：《华北电力大学(北京)》2017年硕士论文

【摘要】：石灰石-石膏湿法脱硫系统是燃煤电站使用最为广泛的烟气脱硫系统,其中吸收塔因为浆液起泡而导致溢流是该系统运行中最常见的问题,解决这一问题的最简单、有效的方法是向吸收塔中投加适量的消泡剂,加快泡沫的破除并抑制泡沫的产生。有机硅消泡剂和聚醚改性有机硅消泡剂具有优异的消、抑泡性能,可以有效解决该问题。基于此,文本通过制备这两种消泡剂,并对其进行性能评价,得到最优配方及其制备方法。首先,本文以二甲基硅油、疏水气相二氧化硅和甲基乙烯基MQ硅树脂组成的硅膏为主要成分,Span60-Tween60为乳化剂,羟丙基甲基纤维素(HPMC)为增稠剂,经乳化剪切后得到性能优异的有机硅消泡剂,并通过实验得到消泡剂最优配方:二甲基硅油(粘度为10Pa·s)为21wt%,疏水气相二氧化硅与甲基乙烯基MQ硅树脂均为1.4wt%,Span60-Tween60复合乳化剂(HLB值为10)为6.3wt%,HPMC为0.5wt%,在3000r/min条件下,剪切处理5min后出料。基于最优条件下的有机硅消泡剂的消、抑泡性能优于同类商业电厂产品,同时具有较好离心、耐热、耐低温、稀释稳定性。同时,为了进一步提升消泡剂性能,研发了聚醚改性有机硅。以聚醚F-6和低含氢硅油为原料,在硅氢加成作用机理下,合成聚醚改性有机硅,其最优制备条件:以0.16%含氢硅油和聚醚F-6为原料,Si-H键和C=C键摩尔比例为1:1.1,加入40μg/g催化剂,在130℃下,反应4h,产品冷却出料,其原料转化率为89.4%,得到具有淡黄色,粘度适中的聚醚改性有机硅,并通过对产品的红外谱图分析确定了其结构。最后,通过在机硅消泡剂中添加聚醚改性有机硅,得到了消、抑泡性能更加优异的聚醚改性有机硅消泡剂,其聚醚改性有机硅的最优含量为5%,同时聚醚改性有机硅可以作为一种助乳化剂,在制备消泡剂过程中,可以有效降低消泡剂主要成分乳化难度。对有机硅消泡剂、聚醚改性有机硅消泡剂不同质量浓度的水溶液的表面张力进行了研究,结果表明,有机硅消泡剂和聚醚改性有机硅消泡剂质量浓度为1.0g/L时分别具有低的表面张力为27.6m N/m、22.6m N/m,聚醚改性有机硅消泡剂具有更低的表面张力,因此具有更好的消、抑泡性能。同时,对有机硅消泡剂、聚醚改性有机硅消泡剂的消泡过程进行了研究,总结归纳出两种自制消泡剂的消泡机理。
[Abstract]:Limestone-gypsum wet desulfurization system is the most widely used flue gas desulfurization system in coal-fired power stations. The effective method is to add a proper amount of defoamer to the absorber to accelerate the foam breaking and to restrain the foam. Silicone defoamer and polyether modified silicone defoamer have excellent anti-foaming performance and can effectively solve this problem. Based on this, the optimal formulation and preparation method were obtained by preparing the two defoamers and evaluating their performance. Firstly, the silicone paste composed of dimethyl silicone oil, hydrophobic vapor silica and methyl vinyl MQ silicone resin was used as the main component, Span60-Tween60 as emulsifier, hydroxypropyl methyl cellulose (HPMC) as thickener, and hydroxy propyl methyl cellulose (HPMC) as thickener. Silicone defoamer with excellent properties was obtained by emulsifying and shearing. The optimum formulation of defoamer was obtained as follows: dimethyl silicone oil (viscosity 10 Pa s) was 21 weeks old, hydrophobic gas phase silica and methyl vinyl MQ silicone resin were 1.4 wtlong and Span60-Tween60 composite emulsifier (HLB = 10) was 6.3wttt. under 3000r/min condition, the 5min was produced after shearing. The antifoaming performance of silicone defoamer based on the optimum conditions is superior to that of the commercial power plants of the same kind, and it also has good centrifugal, heat resistance, low temperature resistance and dilution stability. In order to improve the performance of defoamer, polyether modified silicone was developed. Polyether modified organosilicon was synthesized from polyether F-6 and low-hydrogen-containing silicone oil under the mechanism of hydrosilylation. The optimum preparation conditions were as follows: the molar ratio of Si-H bond to Ca-C bond of 0.16% hydrogen-containing silicone oil and polyether F-6 was 11. 1%, and 40 渭 g / g catalyst was added. At 130 鈩，

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