顺北原油防蜡剂的研制及防蜡机理*

为防止顺北原油管道集输中结蜡,根据顺北原油析出蜡的碳链分布设计合成了以甲基丙烯酸十八酯、醋酸乙烯酯、对苯二乙烯为单体的超支化聚合物防蜡剂,考察了合成条件对防蜡剂防蜡性能的影响,采用冷指法评价了该防蜡剂的防蜡效果并分析了该防蜡剂的防蜡机理。研究结果表明,顺北原油的含蜡量为6.57%,析蜡点为23℃,在环境温度下极易结蜡。优化得到防蜡剂最佳合成条件为:甲基丙烯酸十八酯和醋酸乙烯酯摩尔比为5∶1,对苯二乙烯加量为单体总质量的0.02%,引发剂加量为单体总量的0.7%,聚合温度70℃,聚合时间为6 h。当防蜡剂加量为500 mg/L时防蜡率达到70%以上,表现出良好的防蜡效果。当加入防蜡剂600 mg/L后,原油凝点降低8℃,析蜡点降低13.4℃,防蜡剂与石蜡形成了共晶,破坏了石蜡的晶体结构,抑制了石蜡的继续增长,从而达到防蜡的效果。图19表1参10。

Development of Anti-wax Agent of Shunbei Oil and Anti-wax Mechanism

In order to prevent wax deposition in the gathering and transportation of Shunbei crude oil pipeline,a hyperbranched polymer wax inhibitor was designed and synthesized with octadecyl methacrylate,vinyl acetate and p-phenylethylene as monomers according to the carbon chain distribution of wax separated from Shunbei crude oil.The effect of synthesis conditions on the wax prevention performance of the wax inhibitor was investigated.The wax prevention effect of the wax inhibitor was evaluated and analyzed by cold fingering method,and the wax prevention mechanism was mentioned.The results showed that the wax content of Shunbei crude oil is 6.57%,the wax precipitation point is 23℃,and it is easy to form wax at ambient temperature.The optimum synthesis conditions of the hyperbranched polymer wax inhibitor was as follows,the molar ratio of octadecyl methacrylate and vinyl acetate was 5∶1,the amount of p-phenyleneethylene was 0.02%of the total monomer mass,the amount of initiator was 0.7%of the total monomer mass,the polymerization temperature was 70℃,and the polymerization time was 6 hours.When the dosage of the wax inhibitor was 500 mg/L,the paraffin control rate was over 70%,showing good paraffin control effect.When 600 mg/L paraffin inhibitor was added,the condensation point of the crude oil was reduced by 8℃,and the wax precipitation point was reduced by 13.4℃.The eutectic of paraffin and paraffin was formed by paraffin inhibitor,which could destroy the crystal structure of paraffin and inhibit the continuous growth of paraffin,so as to achieve the effect of paraffin prevention.