低渗储气层低伤害压裂液室内研究及实施

LABORATORY RESEARCH ON LOW-DAMAGE-FRACTURING FLUID FOR LOW-PERMEABILI-TY GAS RESERVOIRS AND ITS APPLICATION

低渗储气藏通常具有低孔、低渗、低压、强水锁等特性,减少外来液体侵入储层,加快压裂液返排,提高压裂液返排率,将直接影响压后的单井产量。文章针对鄂北塔巴庙地区上古生界气藏石盒子组盒1段和山西组山1段,在充分认识储层地质特征的基础上,对N2增能水基压裂液进行了大量的室内研究,尽可能降低由于压裂液侵入储气层而造成的伤害。同时,通过现场实施表明,该压裂液配方体系能较好地满足压裂工艺及储层的物性,提高了压后压裂液返排率,取得较好的单井产量。

In general low-permeability gas reservoir is of these properties, such as low porosity, low permeability low-pressure and strong water locking, etc. In order to increase the individual well productivity after fracturing, it is necessary to reduce extraneous fluid invasion, to quicken fracturing fluid discharge and to enhance its discharge rate. On the basis of considering fully the geological features of P1 sh1 (the first member of Shihezi Formation, Lower Permian) and P1 s1 (the first member of Shanxi Formation, Lower permian) gas reservoirs in Tabamiao field in North E´erduosi Basin, a great number of laboratary researches were carried out for N2 energizing water-base fracturing fluid, so as to reduce the reservoir damage caused by fracturing fluid invasion as far as possible. Through application on the spot, it was indicated that this fracturing fluid formulation system could well meet the needs of fracturing technology and petrophysical property, the fracturing fluid discharge rate being raised after fracturing and the individual well productivity increasing obviously.