应用新型粘性暂堵酸化技术提高气藏产能研究

新型粘性暂堵技术是采用一种粘性酸液体系作为暂堵剂来封堵高渗透层,使酸液转向低渗透层.这种粘性酸液体系在高温下能保持较高的粘度,耐温性能良好,酸化后其粘度能很快降低,对储层伤害小.室内并联岩心实验模拟暂堵酸化,结果表明,暂堵效果较好,由此建立了非均质储层粘性暂堵酸化的数学模型.粘性暂堵技术解决了常规颗粒暂堵剂耐温性能较差的问题,适用于非均质性较强、小层较薄的气藏.采用这项技术在大北气藏进行了暂堵酸化施工,获得了显著的增产效果,采气指数增加了2.2～19倍,对开发类似气藏具有重要的推广价值.

Acidizing techniques for improving gas production in gas reservoir

A novel viscous diversion acidizing stimulation techique for development of Dabei gas reservoir in Tarim Basin of West China was presented. Acid was diverted from the chief zones to the damaged zones by means of viscous fluid plugging agent. This kind of viscous acid can keep relative high viscosity at high temperature and has good properties of anti-temperature, low viscosity after acidizing and low damage to formation. Laboratory test conducted in a parallel core flow apparatus showed good diversion behavior. A numerical model for describing diversion acidizing in heterogeneous reservoir was set up. The applied result showed that this novel technology was suitable for heterogeneous gas reservoir with many and thin layers. The application of this technique improved the gas production significantly during diversion acid treatment in Dabei gas reservoir.