杭锦旗致密砂岩气藏控水压裂材料评价优选研究

Study on Evaluation and Optimization of Water Control Fracturing Materials in Hangjinqi Tight Sandstone Gas Reservoir

致密砂岩气藏是油气田勘探开发的一个重要接替方向。杭锦旗上古生界地层水分为窜层水、凝析水、透镜体水、边底水、气层滞留水等5种类型。将一种控水表面活性剂溶液注入近井地带储层,表活剂与岩石孔壁发生界面修饰作用,通过排驱作用可以将近井地带孔喉的水逐渐排出,降低水膜厚度,增大气相渗透通道,达到控水增气的目的。对这类储层,通过室内研究,按照“疏水”的思路,开展了岩心表面修饰前后接触角测试、表面活性剂界面修饰微观特征及时效性评价、压裂过程中表活剂注入深度实验评价、界面修饰前后岩心气-水相渗实验方法优选评价控水表面活性剂控水材料,为致密砂岩气藏开发提供借鉴。

Tight sandstone gas reservoirs are an important replacement direction for oil and gas field exploration and development.The upper Paleozoic formation water in Hangjin Banner is divided into five types:channeling water,condensate water,lens water,edge and bottom water,and gas retention water.A water-controlling surfactant solution is injected into the reservoir near the well,through interface modification effect of the surface active agent and the rock pore wall,as well as the drainage action,the water in the pore throat near the well can be gradually discharged,reducing the thickness of the water film and increasing the large gas phase infiltration channel to achieve the purpose of controlling water and increasing gas.For this kind of reservoirs,through laboratory research and the idea of"hydrophobic",the contact angle test before and after core surface modification was carried out,as well as the evaluation of the timeliness of the microfeatures of the surfactant interface modification,and the experimental evaluation of the surfactant injection depth during the fracturing process,the core gas-water permeability experiment method before and after the interface modification for optimizing the water-controlling surfactants and water-controlling materials.The paper can provide some reference for the development of tight sandstone gas reservoirs.