摘要
酸液在酸压裂缝内流动时,有少数较大的岩石孔隙或天然裂缝首先受到过量酸液的溶蚀而迅速增长形成蚓孔,使滤失主要在蚓孔内发生。因此研究酸液滤失,必须考虑酸蚀蚓孔的影响。文中剖析了酸压中经由酸蚀蚓孔的酸液滤失机理,建立了单个蚓孔内酸液流动压降计算模型、酸蚀蚓孔的扩展模型、酸液在蚓孔内流动反应模型。分别考虑酸液在酸蚀蚓孔中体积扩展滤失、沿酸蚀蚓孔壁面滤失和蚓孔末端滤失,提出了定量计算酸压中酸蚀蚓孔滤失方法,为酸压施工中控制酸液的滤失提供理论依据。就影响蚓孔增长及滤失的裂缝净压力、酸液粘度等因素进行了计算分析,并分析了蚓孔对酸液有效作用距离的影响。
When acid flow along the fracture, the wormhole was developed because some of rock pore or nature fractures are denuded by the acid, thus the filtrateloss of the acid mostly occurs in wormhole. Therefore, studying the filtrateloss of the acid must take into account the effect of the wormhole. This paper analyzed the filtrateloss mechanism of acid caused by the wormhole and established pressure drop model, wormhole extending model, and flowing and react model for the single wormhole. This paper presents a method on quantitative calculating the filtrateloss of the acid in the wormhole, which includes the filtrateloss caused by the wormhole expansion, the filtrateloss occurred in the wall of the wormhole and filtrateloss occurred in the end of the wormhole. Thus, this paper provides a theoretic basis to control the filtrateloss of the acid for the acid fracturing treatment. This paper analyzes the factors that affect the expansion of the wormhole, net pressure in the fracture and the viscidity of acid. Moreover, the effect of the wormhole on the acid-etched distance is analyzed.
出处
《钻采工艺》
CAS
北大核心
2006年第5期35-38,139,共4页
Drilling & Production Technology
基金
四川省杰出学科带头人培养基金(项目编号:05ZQ026-027)
教育部博士学科点专项科研基金(基金编号:20040615003)资助。
关键词
酸化压裂
蚓孔
滤失
酸蚀距离
数学模型
acid fracturing, wormhole, filtrateloss, acid-etched distance, mathematical model
