新型硫酸盐垢防垢剂的制备与性能评价

Preparation and Evaluation of Novel Scale Inhibitor for Sulfates

根据油田中常用硫酸盐防垢剂的分子结构,设计了一种二元共聚物防垢剂。以马来酸酐(MA)和乙酸乙烯酯(VAC)为单体,氧化还原体系为引发剂,采用自由基水溶液聚合,制得共聚物,再复配以第三单体和增效剂,得到防垢剂产品。分析了合成条件对防垢性能的影响,评价了防垢剂对硫酸钡垢和硫酸钙垢的防垢性能。实验表明,作为油田水处理剂,该防垢剂产品对硫酸盐垢有较好的防垢效果。当马来酸酐与乙酸乙烯酯的摩尔比为6:4,引发剂用量为单体质量的10％, 单体与水的质量比为1:2时,在75℃下反应所得的共聚物防垢效果较好。在聚合体系中加入第三单体A1、A3和增效剂时,得到的聚合物防垢率增加,加入第三单体A2后得到的聚合物防垢率较低。

A kind of bipolymer as a scale inhibitor was designed based on the conventional molecular structure of scale inhibitors for sulfates used on the oilfield. The bipolymer was synthesized from mateic anhydride （MA） and vinyl acetate copolymer （VAC） through free radical polymerization in aqueous solution with redox system as initiator. The effects of synthesis conditions on the antiscaling property were analyzed and the antiscaling property of the bipolymer on the CaSO4 scale and BaSO4 scale was evaluated. The results showed that, as a water treatment agent of oilfield, the product had high scale - inhibiting efficiency for sulfate scale. The best synthetic conditions were as follows：molar ratio of MA to VAC 6：4, mass percentage of initiator 10 % （based on the total mass of reactants）, mass ratio of monomers to water 1 ： 2, reaction temperature 75 ℃. When the third monomer A1, A3 and synergist were added, the scale- inhibiting efficiency increased. When the third monomer A2 was added, scale - inhibiting efficiency decreased.