苏里格气田低渗透砂岩储集层解水锁实验研究

Experimental Study on Water Block Removal of Low Permeability Sand Gas Reservoir in Sulige

水锁效应是气田开发过程中普遍存在的问题,主要表现为在含水饱和度改变后气相渗透率的下降情况。结合苏里格地区的具体情况,提出特定的气井解水锁方案,涉及添加表面活性剂、增大生产压差两类。并在实验室对上述3种方案进行实验模拟研究,并对解水锁方案实验效果进行综合对比。结果表明:对于渗透率较高的气井,宜采用增大生产压差解除水锁效应,措施实施后,渗透率较处理前可提高3.2～3.7倍。对于渗透率较低的气井,可采用注入乙醇的混合溶液后关井一段时间再生产,在实验条件下,措施后渗透率提高率可达到2～2.3倍。

Water blocking effect is common during development of gas field,its main impact is the reducing of permeability when water saturation is changed.In this paper,solutions for Sulige field gas well with water block damage were put forward,such as adding surfactant and increasing production pressure.These methods were studied and compared at lab.The results show that,for high permeability gas well,increasing the production pressure is better for removing the water blocking effect,the permeability can be increased by 3.2～3.7 times.For low permeability gas well,ethanol is used to eliminate the effect,the permeability can be increased by 2～2.3 times.