新型羧酸型聚合物的合成与阻硫酸钙垢性能.doc

新型羧酸型聚合物的合成与阻硫酸钙垢性能中文在制盐、海水淡化、石油开采、盐湖资源综合利用等工业化生产中经常遇到的问题就是硫酸钙垢，垢层的不断加厚，不仅影响传热效率，造成热能损失，使产量降低，还会增加生产成本和延长生产周期。因此研究一种有效合理的除硫酸钙垢的阻垢剂并用于工业化生产具有重大的意义。本论文合成的新型羧酸型聚合物阻垢剂不仅具有制备方法简单、成本低、用量少、功能全，具有比传统阻垢剂更优异的阻垢性能，且仅有碳、氢、氧、钠四种元素，不含对水环境造成二次污染的磷、氮、硫等元素，是一种绿色环保型高效阻垢剂。本文以实验室前期自制的含双键的聚合物单体SXLC分别与市场羧酸物丙烯酸（AA）和甲基丙烯酸（MAA）在水相中聚合，制备出了含羧基的绿色环保型阻垢剂AA-SXLC和MAA-SXLC。用单因素法确定了AA-SXLC的最佳合成条件为：链引发剂用量为单体总质量的6%、引发剂用量为单体总质量的7%、反应温度为80、聚合时间为2h。采用静态阻垢方法系统评价了共聚物阻垢剂AA-SXLC和MAA-SXLC对硫酸钙和碳酸钙的阻垢性能，结果表明：在c(Ca2+) = 6.8gL-1，c(SO42-) = 7.1gL-1，T=70，pH=9.0，t=6.0 h条件下，阻垢剂AA-SXLC和MAA-SXLC分别在用量为2mgL-1和3mgL-1时，阻硫酸钙垢就可达到82.9%和83.6%，与市场阻垢剂阻硫酸钙性能相当，且具有无磷无氮、绿色环保等论文优点，而AA-SXLC更具有很好的耐温和时效性，适合在高硬度高碱度和较宽pH范围内使用。在c(Ca2+)=240 mgL-1，c(HCO3-) = 732 mgL-1，pH=9.0，t=10.0 h的条件下，阻垢剂AA-SXLC比MAA-SXLC有更好的阻碳酸钙效果。在低温50的条件下，MAA-SXLC在浓度高达35mgL-1时，对碳酸钙的阻垢效果仅为60.4%；而AA-SXLC在浓度大于15mgL-1时，对碳酸钙的阻垢效果很好，可以达到90%以上；尽管AA-SXLC在高温80时阻碳酸钙垢效果较差，且剂量大，但在一定的温度、钙离子和碳酸根离子浓度范围内，阻垢性能比较稳定，且不会有钙凝胶生成。同时AA-SXLC和MAA-SXLC都具有良好的分散氧化铁性能，在c(Fe2+) = l0 mgL-1，c(Ca2+) =150 mgL-1，pH=9.0，T = 50 ，t=6.0 h条件下，含氧化铁溶液的透光率分别为21.7%和22.5%，但在达到相近分散效果的情况下，AA-SXLC用剂量更小，为2 mgL-1， MAA-SXLC用量为4 mgL-1。通过测定溶液中钙离子浓度随时间的变化进行了硫酸钙晶体生长的动力学研究，结果表明阻垢剂的添加可以推迟钙垢的析出时间而使诱导期增长，沉积速率减慢，并维持较高的过饱和度，因此动力学研究可以用于阻硫酸钙垢性能的评定和优化。译文In the industrial production, the problem of calcium sulfate scale is offen encountered, especially in the salt production, sea water desalination, oil drilling, comprehensive utilization of salt lake resources. With the passage of time, the scale layer will be thicker. This not only affects the heat transfer efficiency of the pipelines, but also causes the heat loss, result in production costs increased and the production cycle extended.Therefore, the study of a reasonable effective inhibitor, be used to remove calcium sulfate scale in industrial production, is of great significance. In comparison with traditional inhibitors, the new type carboxylic acid polymer scale inhibitors easily prepared with lower cost, reliable reproducibility and less dosages, had exhibited superior performance as multi-function inhibitors. Furthermore, the synthesized AA-SXLC and MAA-SXLC in this thesis belong to the environment friendly inhibitors, only containing four elements of carbon (C), hydrogen (H), oxygen(O), sodium(Na), and is non-phosphorous (P), non-nitrogen (N) and sulfur (S) free, which are potential nutrients for algae. In this paper, monomer allyloxy polyethoxy carboxylate (SXLC), synthesized in our own laboratory before, acrylic acid (AA) and methacrylic acid (MAA) were used as materials to produce. AA or MAA and SXLC were all placed in water to make free radical polymerization of AA or MAA with SXLC to produce acrylic acid-allylpolyethoxy carboxylate (AA-SXLC) and methacrylic acid-allylpolyethoxy carboxylate (MAA-SXLC) copolymer scale inhibitors which contained carboxyl groups. Using single factor analytic method determined the best synthesis conditions of AA-SXLC and the results were as follows: dosages of chain transfer agent and initiator were about 6% and 7% of the monomers total mass; reaction temperature was 80 and reaction time was 2.0 h. Combining the above results, two rationally designed inhibitors AA-SXLC and MAA-SXLC were synthesized, whose performances on calcium sulfate and calcium carbonate inhibition were evaluated by static test. AA-SXLC and MAA-SXLC exhibited excellent ability to inhibit the precipitation of calcium sulfate, respectively showing 82.9% and 83.6% inhibition under the conditions of 6.8gL-1Ca2+, 7.1gL-1 SO42-, T=70 , t=6.0 h and at a level of 2 and 3 mgL-1.Compared with MAA-SXLC and other market scale inhibitors, AA-SXLC not only had very good scale inhibition performance, but also had other advantages, such as higher heat resistance, timeliness, no phosphorus and nitrogen and a wider range of use and so on. Under the conditions of 240 mgL-1Ca2+, 732 mgL-1 HCO3-, T=80, t=10.0h, AA-SXLC showed more superiorer inhibition for CaCO3 than MAA-SXLC. At low temperature, calcium carbonate inhibition of MAA-SXLC was only 60.4% at a level of above 35 mgL-1, but AA-SXLC was above 90% at a level of above 15 mgL-1. At high temperature, although efficiency of calcium carbonate scale was poorer, and using doses were larger, but in a certain temperature, calcium ions and sulfate ion concentration range, scale inhibition performance was stable and no calcium gel generate. It was also shown that they all had excellent dispersancy activity towards Fe2O3, about 21.7% and 22.5% light transmittance under the conditions of 150 mgL-1 Ca2+, 10 mgL-1 Fe 2+, T=50 , t=6.0 h. But in the similar effect to scattered, the doses of AA-SXLC were less, only 2 mgL-1, than MAA-SXLC with 4 mgL-1. The precipitation thermodynamics and kinetics of calcium sulfate at different temperature were also discussed. The results show that the addition of the inhibitors, in the same conditions of temperature a