稠油井过泵旋流混合降黏举升技术

Lifting Technology by Swirl Pumping Vortex-Reducing Viscosity for Heavy Oil Production Well

针对稠油机抽井油套环空添加降黏剂时存在降黏剂与产出液混合不均匀、降黏效果差和不能充分发挥降黏剂效能等问题,开展了稠油井过泵旋流混合降黏举升技术研究。稠油井过泵降黏举升技术是通过地面注剂系统将降黏剂输送到空心杆,再利用井下过泵系统中的空心中心杆将降黏剂释放至泵下,通过旋流混合系统叶轮的旋转作用,充分搅拌降黏剂和产出液,使其混合均匀,达到提高降黏剂效能和降黏效果的目的。该技术适用于泵深小于1 500.00m、产液量小于50m^3/d的稠油机抽井。该技术在胜利油田21口稠油机抽井中进行了应用,平均泵效提高了11%,累计增油5 310m^3,累计节约降黏剂9t,生产周期平均延长81d。研究结果表明,稠油井过泵旋流混合降黏举升技术能充分发挥降黏剂效能,降黏增油效果明显,应用前景广阔。

Conventionally, viscosity-reducing additives are deployed in annular spaces between tubing and casing to develop heavy oil, these operations are featured with uneven mixing of additives and produced fluids, poor viscosity-reducing performances and the low-efficiency of such additives. Under such circumstances, research has been conducted to reduce viscosity by swirl pumping in heavy oil producers. Its principle is that the viscosity-reducing additives can be injected into the hollow rod by the ground mixing system, and then placed under the pump by means of a central hollow rod. The rotation of propellers in the mixing system can sufficiently mix the produced fluids with a viscosity-reducing additives to generate an evenly dispersed mixture, by which the maximum efficiency of a viscosity-reducing additives and optimal performances can he achieved. This innovative technology is suitable for the heavy oil producers with depths of less than 1 500.00 m and fluid productivity of no more than 50 m3/d. It has been deployed in 21 heavy oil producers in the Shengli Oilfield with average pumping efficiency increment of 11%, accumulative oil increment of 5 310 m3 , total reduction in consumption of viscosity-reducing additives of 9 t, and the extension of average production cycle for 81 d. Research results showed that the newly viscosity-reducing technology using pumping swirl for heavy oil production can give full play to the effectiveness of viscosityreducing additives, with obvious oil increasing the effects with prospects for broad applications.