乳化石蜡的优化制备及其降滤失作用

鉴于南海西部油田检泵作业中修井液大量漏失,且产油恢复时间长,拟选用乳化石蜡解决伤害问题,然而市售的大多数乳化石蜡抗温抗盐性差,不能满足需要.因此对乳化石蜡的生产工艺进行了优化,并使用非离子表面活性剂、辅助磺酸盐型表面活性剂ODS,制备出了一种在模拟海水中可以稳定分散的乳化石蜡,其具有一定的抗温抗盐能力；使用质量浓度为5％的乳化石蜡溶液可使滤失速率降低80％,并通过润湿反转和贾敏效应使后续盐水的滤失量降低80％,根据此特点可以在乳化石蜡封堵后转用海水压井,从而减小乳化石蜡的用量；油相渗透率的恢复率超过100％,有一定解除水锁效应的作用,且渗透率的恢复时间短.

Preparation and Filtration Control Evaluation of Emulsified Paraffin

In view of formation damage characterized by the prolonged recovery of oil production due to the heavy filtration loss, the emulsified paraffin, as drilling fluid additive, is employed.The market products are unsatisfied with the requirement for temperature and salinity situation, so a qualified emulsion with steady dispersion in simulated seawater and desirable heat and salinity tolerance was produced by preparation optimization and sulfonated surfactant ODS assisting nonionic surfactant.The experimental results show that filtration loss rate is reduced by 80% with the solution containing 5% emulsion, then decreased by 80% with simulated seawater after that emulsion injection, and the return permeability recovered completely with oil in a short period.