丙烯酸酯-甲基丙烯酸共聚物乳液反相破乳剂的制备及应用

Preparation and Application of Acrylate-methacrylic Acid Copolymer Emulsion Reverse Demulsifier

海上油田污水处理设备少,停留时间短,对污水处理药剂要求极高。为了提高油水分离效果,提升污水处理水质,以丙烯酸乙酯(EA)、甲基丙烯酸(MAA)和丙烯酸十八酯(SA)为原料,通过乳液聚合法制备了丙烯酸酯-甲基丙烯酸共聚物乳液型反相破乳剂(EMASA)。对EMASA的结构进行了表征,并以除油率为主要指标通过瓶试法考察其净水性能,最后在海上油田A平台开展现场中试试验,分析了EMASA反相破乳机理。结果表明,合成产品的实际结构与理论结构相符,EMASA的热分解温度为214.5℃。EMASA的净水效果优异,在最优加注量(30 mg/L)下的除油率为96.5%;协同现场絮凝剂的除油率为98.9%。在现场中试试验中,当EMASA的加量为30 mg/L时,分离器出口水中的含油量由255.75 mg/L降至197.58 mg/L,降低22.74%,除油率由95.5%提高至96.52%。EMASA利用卷扫和破坏油水界面膜强度两种作用实现油水分离,在处理碳酸氢钠水型采出液时的效果明显。

Requirements for sewage treatment chemicals are very high due to the limited sewage treatment equipment and short residence time in offshore oilfield.Thus,it is necessary to develop a high-efficient reverse demulsifier to improve the separation efficient of oil and water.The acrylate-methacrylic acid copolymer emulsion reverse demulsifier(EMASA)was synthesized via emulsion polymerization method by using ethyl acrylate,methacrylic acid and stearyl acrylate as precursors.The structure of EMASA was characterized,and its water purification performance was investigated by bottle test method with oil removal rate as the main index.Finally,the field pilot test was carried out on the platform A of offshore oilfield,and the reverse demulsification mechanism of EMASA was analyzed.The results showed that the actual structure of synthesized product was consistent with the theoretical structure,and the thermal decomposition temperature of EMASA was 214.5℃.The water purification effect of EMASA was excellent.The oil removal rate under optimal injection amount(30 mg/L)was 96.5%,and the value further increased to 98.9%under the help of synergistic flocculant.In the field pilot test,when the dosage of EMASA was 30 mg/L,the oil content in outlet water of separator decreased from 255.75 mg/L to 197.58 mg/L,with a decrease of 22.74%,and the oil removal rate increased from 95.5%to 96.52%.EMASA used two effects such as rolling sweep and destroying the strength of oil-water interface film to achieve oil and water separation.The effect was obvious in the treatment of produced fluid with sodium bicarbonate water-type.