周期注水提高油藏采收率技术研究
Research on Cyclic Water Injection Technology to Improve Reservoir Recovery Rate

周期注水驱油就是在一定的注采井网上，对注采井采取开注、停注、转注、增注等措施，在油层中形成变化的压力(势)，不断改变注采井网中压力分布的强度，使注入水在层间压差作用下发生渗流，增大毛管渗吸作用；同时能够改变流体在油层中的流向，促进地层流体重新分布，扩大注入水波及系数，提高原油采收率，其主要优点是能充分利用现有井网，通过压力场的调整，使常规水驱时滞留的原油得到动用，扩大注入水的波及体积，提高注入水利用率，从而提高水驱的采收率。
Cyclic water injection for oil recovery refers to taking measures such as starting, stopping, transfer-ring, and increasing injection on a certain injection production well network, forming a changing pressure (potential) in the oil layer, continuously changing the intensity of pressure distribution in the injection production well network, causing the injected water to flow through under the pres-sure difference between layers, and increasing the capillary suction effect; At the same time, it can change the flow direction of fluids in the reservoir, promote the redistribution of formation fluids, expand the injection water sweep efficiency, and improve crude oil recovery. Its main advantage is that it can fully utilize the existing well network, adjust the pressure field, and utilize the crude oil that is retained during conventional water flooding, expand the swept volume of injected water, improve the injection water utilization rate, and thus improve the water recovery rate of water flooding.