水力脉冲波协同多氢酸酸化解堵反应动力学模型

Kinetic model of plug removal reaction based on a synergy between hydraulic pulse wave and multi-hydracid acidification

水力脉冲波协同多氢酸酸化技术对于高压注水、注汽井近井区域的储层堵塞具有高效的解堵效果。但目前针对该项技术的模拟理论及动力学研究较少,现场工艺参数设计存在一定的盲目性。基于多氢酸活性酸组分的酸岩反应模型,以水力脉冲波传播动力学为基础,构建了水力脉冲波协同多氢酸酸化反应动力学模型;研究了孔隙度、渗透率、酸液及矿物浓度随时间和距离的变化规律,分析了水力脉冲波协同多氢酸酸化解堵的参数敏感性,并进行了矿场应用分析。研究表明:协同作用进一步提高了储层的酸化解堵效果,明显改善了酸液流速、酸液及矿物浓度的分布;振幅、频率较高时,酸液流速的径向差异直接影响相邻位置的解堵效果。针对不同类型的砂岩油藏设计了水力脉冲波协同多氢酸酸化解堵参数,并成功开展11井次矿场试验,注水压力平均下降6.3MPa,注汽压力平均下降3.5 MPa,起到了显著的解堵降压增注效果。

The synergetic technology between hydraulic pulse wave and multi-hydracid acidification shows a highly-efficient plug removal effect against reservoir plugging in the vicinity of high-pressure water and steam injection wells.However,currently there is seldom research on the simulation theory and kinetics of such technology,and a certain blindness exists in the field process parameter design.The kinetic model of a synergy between hydraulic pulse wave and multi-hydracid acidification reaction was established based on the acidic rock reaction model of multi-hydracid active acid components as well as the transmission dynamics of hydraulic pulse wave;a study was conducted on the variation laws of porosity,permeability,acid and mineral concentration over time and distance.Meanwhile,the parameter sensitivity of a synergy between hydraulic pulse wave and multi-hydracid acidification for plug removal was analyzed.Finally,field application analysis was also carried out.The results show that the synergy effect further enhances the acidizing plug-removal effect of reservoirs and obviously improves the distribution of acid flow rate,acid and mineral concentration.In case of high amplitude and frequency,the plug removal effect at adjacent positions is directly influenced by radial difference in acid flow rate.Aiming at different types of sandstone reservoirs,the plug removal parameters based on a synergy between hydraulic pulse wave and multi-hydracid acidification are designed to successfully carry out field tests in11 wells.The average reduction of water and steam injection pressure is 6.3 MPa and 3.5 MPa respectively,leading to significant effects on plug removal,pressure reduction and injection stimulation.