浅层砂岩气压裂优化设计和现场应用

Fracture Design Optimization and Field Application in Shallow Sandstone Gas

浅层砂岩气藏是中国最具现实勘探开发意义的非常规天然气领域,由于其成因、成藏机理与常规天然气不同,目前在储层改造方面仍存在许多难点,压裂成功率及改造效果不理想。以鄂尔多斯盆地东部地区浅层砂岩气藏为研究对象,针对其低孔、低温、低压的储层特征,在总结分析前期施工井失败原因的基础上,对储层物性等参数进行系统分析,结合压裂机理,通过压裂液滤失特征分析和压裂液配方优选,以及现场测试压裂实时分析结果,调整主压裂,对整体压裂方案进行优化,成功完成了两口井的压裂施工。现场应用效果明显,初步形成了适合于该地区浅层砂岩气藏的压裂增产改造工艺,为盆地东部和北部低渗气藏有效开发提供了重要依据。

Shallow sandstone gas reservoir is the most realistic significance of exploration and development in the unconventional natural gas area in China. However, because the accumulation mechanism is totally different from the conventional nature gas, many difficult problems exist in reservoir stimulation. Therefore, the fracturing success rate is low, and modification effect is not ideal. In this paper, with the shallow sandstone gas reservoir in the East Erdos Basin as the study object, systematic analysis has been con- ducted on the reservoir physical properties in view of the low temperature low pressure and low porosity reservoir characteristics, the reasons for early fracturing failure have been summarized. Combined with fracturing mechanism, through analysis of the fracturing fluid filtration characteristics and optimization of fracturing fluid formula, in site real-time fracture results were analyzed, the master fracturing was adjusted, and the whole fracturing scheme was optimize. Through these measures, stimulation operation has been carried out successfully in two wells. Field fracturing effect is obvious, and fracture stimulation technology suitable for the shallow sandstone gas reservoir has been found in this area, which provide important supports for the effective development in east and north area in Erdos Basin.