白云岩气藏基质酸化后产能预测方法研究

解堵酸化是白云岩储层广泛采用的油气层改造措施,在评价白云岩气藏酸化效果和经济效益时必须进行气井酸化后产能预测.白云岩储层基质酸化过程中会形成酸蚀蚓孔,酸蚀蚓孔的穿透距离直接影响到气井的酸化效果,即气井的酸化后产量.由于气体渗流的特殊性和酸蚀蚓孔的复杂性,使得气井酸化后产能的预测更加复杂.在对酸蚀蚓孔穿透距离和表皮系数研究的基础上,将其与气体渗流结合起来,导出了一种考虑酸蚀蚓孔效应的预测白云岩气藏酸化后气井产能的新方法.通过实际生产数据的对比,符合程度较高,可以应用于现场生产.

Method for Productivity Prediction after Matrix Acidizing in Dolomite Gas Reservoirs

Blocking removal and acidization are the techniques widely used for reservoir reconstruction in dolomite reservoirs, when it is used for acidizing economic efficient evaluations on dolomite gas reservoirs, productivity prediction is made after gas well acidization, wormholes are created during the acidizing process. The penetration distance of wormhole would directly influence the effect of gas well acidization, that is the production output after acidizing. Because of the specialities of gas filtration and the complexity of wormholes its productivity prediction is more complex after gas well acidization. On the basis of studying the acidizing wormhole penetration distance and skin factors, and in combination with gas percolation, a new method is established for gas well productivity prediction in dolomite gas reservoirs, by which the effect of acidizing wormholes is taken into account. The comparison of production data shows that it has high conformity and can be used in field production.