苏桥储气库酸化解堵工艺研究与应用

Research and Application of Acidizing and Blocking Removal Technology for Suqiao Gas Storage

摘要: 苏桥储气库钻井和修井作业中的压井液会对储层造成污染，导致储层渗透率下降，储气库注采井注采能力降低。为了解决储气库井筒周边污染造成的注采能力降低的情况，通过采用基质酸化技术对苏桥储气库注采井井筒周边污染进行酸化解堵，并根据苏桥储气库碳酸盐岩储层高温、高压、埋藏深等特征，进行室内试验，优选出酸化配方和酸化体系，通过实际酸化施工曲线可以看出，该酸化体系具有良好的解堵功能，能有效清除井筒附近固相颗粒物和矿物颗粒等污染物，对地层污染小，有效解决了苏桥储气库注采井近井污染的难题。该酸化体系具有优良提升储层裂缝通道的导流能力和改善岩心渗透率的能力，在碳酸盐岩地层储气库注采井的解堵作业中具有广阔的推广应用前景。

Abstract: The killing fluid in the drilling and work over operations of the Suqiao Gas Storage will pollute the reservoir, resulting in a decrease in reservoir permeability and a reduction in the injection-pro- duction capacity of the gas storage’s injection-production well. In order to solve the situation of reduced injection and production capacity caused by pollution around the wellbore of the gas storage, the matrix acidification technology is used to acidify and remove the pollution around the wellbore of the injection and production well of the Suqiao Gas Storage, and according to the carbonate rock of the Suqiao Gas Storage Reservoir features such as high temperature, high pressure, and depth of burial have been tested in-house, and the acidification formula and acidification system are optimized. According to the actual acidification construction curve, it can be seen that the acidification system has a good plugging removal function and can effectively remove solid particles near the wellbore. Pollutants such as mineral particles and other pollutants have little pollution to the formation, effectively solving the problem of near-well pollution of the injection and production wells of Suqiao Gas Storage. The acidification system has excellent ability to enhance the conductivity of reservoir fracture channels and improve core permeability, and has broad application prospects in the removal of plugging operations of gas reservoirs in carbonate formations.