摘要
生物酶破胶剂具有破胶彻底、残渣量少、对地层的伤害小等优点。介绍了适用于高、中高、低温条件的3种生物酶破胶剂,通过室内实验,对生物酶的配伍性、生物酶浓度、瓜胶浓度、pH值、温度等条件对酶活性及破胶效果的影响进行了评价。结果表明,该3种生物酶与压裂液添加剂的配伍性好;酶浓度在5～20mg/L、瓜胶浓度在0.2%～1.0%范围内时具有很好的破胶效果;生物酶破胶剂在pH值为5～10、温度为20～120℃范围内,3h可将压裂液黏度降低到5mPa·s以下,达到行业标准;与化学破胶剂相比,生物酶破胶剂用于压裂液,不仅破胶可控,而且破胶后破胶液黏度低、破胶聚合物分子量小、残渣含量少,环境保护性能好。
Bio-enzyme breaker can degrade guar gum into small molecules and do little harm to reservoirs.This paper introduces three kinds of bio-enzymes that work at low medium and high temperature.Some affecting factors of enzyme activity and breaking efficiency are evaluated,which includes compatibility,concentration,pH and temperature.The experimental results show that the three enzymes have good compatibility with field chemicals,and the best conditions for breaking gum are the enzyme concentration 5-20 mg/L,substrate concentration 0.2%-1.0%,pH value 5-10 and temperature 20-120 ℃.The fracturing fluid viscosity can be reduced to below 5 mPa·S within 3 h which meet the national standards.Compared with other chemical gel breakers,bio-enzyme breakers have some advantages such as gel-breaking time controlling,low viscosity after breaking,small molecular weight,little residue,environmental protection and so on.
出处
《钻井液与完井液》
CAS
2010年第6期68-71,共4页
Drilling Fluid & Completion Fluid
