海上常规稠油油田前期通常采用注水开发,由于原油黏度相对较高;并且目标储层黏土矿物含量较高,存在较强的水敏现象等原因,稠油油田注水开发效果逐渐变差.为此,以新型改性烷基磺酸盐为主要降黏驱油剂,通过复配以非离子表面活性剂、渗透剂以及高效防膨剂,研制出了一种适合于目标稠油区块的新型复合降黏驱油体系.分析了复合降黏驱油作用机理,并进行了室内实验评价.结果表明,新型复合降黏驱油体系能够有效降低稠油黏度,降低油水界面张力,对储层钻屑具有较好的防膨作用;并且与地层水的配伍性良好;该体系可以使岩心水驱后的采收率提高30％以上,具有良好的降黏驱油效果.现场应用结果表明,经新型复合降黏驱油体系处理的三口井,平均日产油量提高48.6m3/d,平均含水率下降82.7％,达到了良好的增产效果.%Water injection is usually used in the early stage of conventional offshore heavy oil field,due to the relatively high viscosity of crude oil,and the target reservoir clay mineral content is higher.There is a strong water sensitivity,and other reasons,the development of heavy oil field water injection effect is gradually getting worse.Therefore,new modified alkyl sulfonate was used as the main viscosity reducing agent,by compounding with non ion surface active agent,penetrant and efficient anti swelling agent developed a new type of composite viscosity reduction and oil displacement system for the target heavy oilfield.The action mechanism of the compound viscosity reducing oil displacement was analyzed,and the indoor experiment was carried out.The results show that the new type of composite viscosity reduction and oil displacement system can effectively reduce the viscosity of heavy oil,reduce the interfacial tension of oil and water,and has better anti swelling effect on the reservoir drill cuttings,and also has good compatibility with formation water.This system can make the core recovery increased by more than 30％ after water flooding,has a good viscosity reducing and oil displacement effect.The application results of three wells in the field show that the average daily oil production increased by 48.6 m3/d,and the average water content decreased by 82.7％ after treated with the new type of composite viscosity reduction and oil displacement system,which reached a good effect of increasing production.
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