SD土酸解堵酸化体系研究与应用

STUDY AND APPLICATION OF ACIDIZING SYSTEM WITH SD MUD-ACID FOR BREAKDOWN

四川盆地裂缝—孔隙型(或裂缝型)砂岩气藏普遍具有低渗透和裂缝性的特点。各种钻完井液对砂岩储层的损害严重,四川石油管理局井下作业处研究开发了SD土酸解堵酸化体系,该酸液体系以解除泥浆污染堵塞为主要目的,具有优良的配伍稳定性,特别对粘土及漏入储层堵塞孔道的泥浆等堵塞物具有较好的溶解能力,能达到解堵、恢复储层产能的效果。该土酸体系还可作为加砂压裂的预处理液,具有降低地层破裂压力、改善储层可压裂性的功效,具有很好的推广应用价值。文章主要介绍了 SD土酸解堵酸化体系的作用原理、性能、现场配制及安全防护与施工应用,并介绍了解堵酸化井的评层选井要点,为了能使土酸解堵酸化获得更理想的增产效果,就必须综合分析静、动态地质资料,充分认识储层的潜在增产能力,来决定是否进行土酸解堵酸化。同时也简单介绍了措施井的后期管理。

The fracture-porous (or fractured) sand gas reservoirs have the characteristics of low permeability commonly in Sichuan basin. Different drilling and completion fluids damage the sand reservoirs severely. SPA Down-hole Service Department Develops the acidizing system with SD mud acid for breakdown. The major propose of the acidizing system is to remove the plugging from mud pollution. The acidizing system has good matching stability and solubility especially for the plunging materials such as clay and mud that leaks into the reservoirs and plugs the pore channels, etc. It can achieve the effects of breakdown and restoring the reservoirs productivity. The system can also act as the penetrating fluid of sand fracturing, which has the effect to decrease the formation cracking pressure and improve the fracturing performance of reservoirs. It is worth to apply and popularize. The article introduces the working principle, property, field preparation, safeguard and operation of the acidizing system with SD mud acid for breakdown. Also the key points are explained for formation evolution and well choice to conduce the acidizing breakdown. To achieve ideal production-increasing results by acidizing breakdown with mud acid, it is necessary to comprehensively analyze the static and dynamic geologic data, fully understand the potential production-increasing ability of reservoirs, and determine whether or not conduct the acidizing breakdown with mud acid. The late-stage management is introduced briefly too for the acidized wells.