生物破胶酶研究及应用

针对压裂过程中压裂液常规化学破胶剂存在化学污染、破胶度有限等缺陷,根据生物酶破胶原理,利用国内独特的极端微生物资源,筛选出产半乳甘露聚糖酶的嗜碱菌和产半乳甘露聚糖酶的嗜热菌,开发出具有破胶性能的生物酶制品。介绍了筛选获得的嗜热菌DC-AW 6产生酶的特性,生物破胶酶的作用温度、使用浓度、岩心伤害、与压裂液添加剂的配伍性等,并在鄂尔多斯盆地延长油田2口井现场应用压裂液生物破胶酶获得成功。试验表明,生物破胶酶最佳作用温度40~80℃,压裂液酶法破胶后岩心伤害率为15%~25%,破胶残渣7%~8%,现场应用中压裂液的返排率达72%~75%,返排黏度为1.8~2.8 mPa·s。生物酶破胶彻底,使压裂液对地层的伤害降低到最小,在压裂工艺中具有较广泛的应用前景。

Study and application of biology viscosity break ferment

In view of chemical contamination and finite viscosity break of normal fracture fluid,based on viscosity break principle of biology ferment,selected galactomannan alkali bacterium and thermophilic bacterium,developed biology ferment with viscosity break performance.Introduced properties of thermophilic bacterium DC-AW6,such as acting temperature,apply concentration,core damage,compatibility with fracturing fluid.Applied this bacterium to two wells of Yanchang oilfield and obtained success.The acting temperature of biology viscosity break ferment is 40-80 ℃,core damage is 15%-25%,breaking residua is 7%-8%,flowback ratio is 72%-75%,flowback viscosity is 1.8-2.8 mPa·s.Experiment shows it has well performance and application foreground.