多氢酸酸化技术及其应用

砂岩储层酸化的常规土酸体系存在与矿物反应速度快、酸化液的有效距离短和容易产生二次沉淀等问题。现存的缓速酸酸液体系不能克服粘土和石英界面反应速率的巨大反差,新的深度酸化工艺可以在一定程度上增加酸液的穿透距离,但工艺繁琐,且仍然不能解决沉淀、堵塞问题。多氢酸体系与现存的HF酸体系相比,其反应速度慢,溶解能力强,且具有良好的防垢性能和分散性能,可以抑制井眼附近的地层伤害,有效控制二次沉淀等优点。本研究对多氢酸的酸度特性、溶蚀性能、润湿性、静态腐蚀性以及多氢酸的分散和防垢性能进行了室内测试,并对土酸、氟硼酸及多氢酸进行了酸化效果实验评价。室内实验及现场应用表明,多氢酸性能优越,可明显提高酸化效果。

THE ACIDIZING TECHNOLOGY AND APPLICATION OF MULTI- HYDROGEN ACID

In sandstone reservoir acidizing,there are problems of conventional mud acid system that it reacts with minerals too quickly,secondary precipitation happens easily and the effective distance of acid liquid is short.The existing retarded acid system can not overcome the huge contrast of the reaction speed between clay and quartz interfaces,new deep acidizing technique can increase the penetration distance of acide liquid in a certain degree though,the technique is complicated and it can not solve the problems of precipitation and block-out.The multi-hydrogen acid system,compared with existing HF system,reacts more slowly,is more capable of dissolution and anti-scaling and dispersivity property,it can constrain formation damage nearby well bore and effectively control secondary precipitation.The acidity characteristics,dissolving property,wettability,stastic corrosion property,dispersivity and anti-scaling property of multi-hydrogen acid are tested in-door,the aciding effectiveness test of mud acid,fluoboric acid and multi-hydrogen acid is evaluated.Case study indicates the multi-hydrogen acid is excellent in property and acidizing effectiveness can be enhanced considerably.