热污水压裂液技术研究及应用

The research and application on the technology of hot sewage fracturing fluid

低渗透高凝油藏压裂开采的一个难点是冷伤害,热压裂液技术是一项有效的技术措施。热污水压裂液技术是一项简便可行的技术,其具有成本低廉,配置方便,与地层配伍性强等特点。但是,油田回注污水含有固体杂质、油及细菌易对储层造成伤害,且矿化度高、pH值低、含有大量的二价金属离子易造成交联性能差,与压裂添加剂配伍性差等特点。本文从分析油田回注污水的性质出发,分析了热污水配置压裂液的难点,提出了解决思路并通过试验优化出了热污水压裂液的最佳配方.用试验的方法对热污水压裂液体系的性能进行了测试,试验结果显示交联耐温性能、破胶性能均满足压裂施工需求,伤害性能与清水压裂液相近,最后进行了现场应用获得了成功。本研究为低渗透高凝油的压裂开采提供了一套切实可行的方法。

Cold damage is one of the difficulties to mine low permeability and high pourpoint oil reservoir using fracturing method.Hot fracturing fluid technology is an effective technical measure.Hot sewage fracturing fluid is a simple feasible technology which has many characteristics,such as low cost,easy compatibility with strata.But,it has many disadvantage,such as oilfield produced water contains solid impurity,oil and bacteria which cause damage to the reservoir easily,high salinity,low pH value,containing a lot of divalent metal ions which easy cause cross linking performance and compatibility with fracturing additive to be poor.Based on the analysis of the oilfield produced water,this paper analysis the difficulty to carry out fracturing fluid with hot oilfield produced water,then the solution was proposed and optimization test were done,as a result the best formula of fracturing fluid were brought out.Again experiments were done to know the properties of sewage fracturing fluids.The results showed cross -linking and heat -resistant performance were good,gel breaking properties were satisfied with fracturing,and damage performance close to fracturing liquid made by clear water.Finally this result was conducted in reality.This provides a series of feasible method to mine low permeability high pour—point oil reservoir.