深层碳酸盐岩储层新型酸压液体体系研究现状

Research situation of the new acid fracturing acid system applying to deep carbonate reservoir

酸压是油气井增产增注的重要措施之一,选择适当的酸液体系对酸压施工十分重要。本文主要论述了深层碳酸盐岩储层酸压改造难点及应对措施,概述了新型碳酸盐岩储层酸压液体体系的国内外发展现状,分析了每种新型酸压液体体系的作用机理、特点及应用。新型酸压液体体系总体发展趋势为"低伤害,低成本,低滤失,低反应速度,高溶蚀效果"。清洁自转向酸的分流转向效果良好,遇烃自动破胶,易返排,无污染。常规乳化酸滤失量小,缓速性能好,能进入地层深部,是目前最为常用的缓速酸液。缓蚀剂在外相的新型乳化酸,使得缓蚀剂更快速地分散在管道金属表面形成保护膜,防止酸液对管道表面的腐蚀,可使酸液进入更深的地层。纳米微乳酸分子直径为纳米级,具有极低的界面张力,黏度低,易泵入。无伤害合成酸对人类健康无伤害,溶蚀能力与盐酸相当,在当今提倡的环保型社会中,这种酸液具有很好的发展前景。复合酸克服了单一酸液的局限,发挥各种酸压液体的优点,适用于不同类型的复杂碳酸盐岩储层。

Acid fracturing is one of the key methods in oil and gas stimulation,it is vital to choose a appropriate acid for acid fracturing treatment.This paper discusses that the difficulties and contermeasures of acid fracturing stimulation to deep carbonate reservoirs,summarize the current state of the new acid fracturing fluids applying to carbonate reservoirs,analysis the mechanism,characteristics and application of the new acid fracturing fluids.The overall trend of the new acid fracturing fluid system is ＂low damage,low cost,low filtration,low reaction rate and high dissolution effect＂.Clean self-diverting acid has good shunt and diversion effect, the case of hydrocarbon automatic broken,easy to return row,no pollution.Conventional emulsified acid has little filter,high retarded performance,which can enter the deep formation,is the most commonly used retarded acid.The new type of emulsified acid which corrosion inhibitors in the external phase can be quickly dispersed in the pipeline metal surface to form a protective film to prevent the acid on the pipe surface corrosion,so that acid can enter the deeper formation.Nano microemulsion acid has nano-scale molecular diameter,low interfacial tension,low viscosity and easy to pump.The new synthetic acid has no harm to human health,dissolution capacity is similar to hydrochloric acid. In today＇s environmental-friendly society,this acid has a promising future.The complex acid overcomes the limitations of the single acid,exerts the advantages of various acid pressure liquids, and is suitable for different types of complex carbonate reservoirs.