高温低伤害压裂液性能优化与应用

Optimization of the fracturing fluid with minor formation damage and for high temperature use

中原油田应用的压裂液存在着残渣含量高、表面活性差、地层损害程度严重等问题。针对深井高温地层压裂改造的要求,采取了降低成胶剂残渣含量、提高液体表面活性、稳定地层粘土矿物、改善交联体系以及实行分段破胶等技术措施,使压裂液具有良好的高温稳定性与地层保护能力。新的压裂液体系主要由低残渣羟丙基胍胶、HY-605和HF-605高活性复合表面活性剂体系、新型油溶性树脂、复合型粘土稳定剂和高温延迟交联剂OB-99组成。高温低伤害压裂液体系在现场3井次应用表明,该压裂液保证了高砂比、大排量和复杂工艺条件下的压裂施工顺利进行,取得了显著的增产效果,压后初期日增油量为51.3 t,累计增油量为4900 t;日增天然气量为8300 m^3,累计增气量为124.5×10~4m^3。

The conventional fracturing fluid used in Zhongyuan oilfield has high residue content and poor surface activity, and causes serious formation damage. To make it more suitable for using in the deep wells of high temperature, such measures have been taken as reducing the residue content of the gelling agent, increasing the surface activity of the fracturing fluid, stabilizing the clay minerals in formation, improving the performance of the cross-linking system- and conducting segmental gel breaking, etc. The optimum fracturing fluid mainly consists of low residue hydroxypropyl guanidine gum, HY-605, HP-605) high activity composite surfactant . novel oil-soluble resin, composite clay stabilizer, and high temperature delayed crosslinker OB-99. The new fracturing fluid system has been used in 3 wells, and the results showed that the fracturing operations were successful even under high sand ratio, high pump rate and complex downhole conditions. Remarkable production rises have been found in the three wells after the fracturing stimulations, the oil and gas production rate increased by 51. 3 t/d and 8300 m3/d respectively, and total accumulations reached 1900 t and 121. 5× 10 4 m3.