抗高温无黏土相钻井液体系研究与性能评价

为了使钻井液摆脱对黏土的依赖,较好地保护油气储层和提高钻井速度,通过引入磺酸基团和阳离子单体,合成了增黏降滤失剂SSDP;对增黏剂、降滤失剂、润滑剂和防塌抑制剂进行优选和复配,研制出了抗高温无黏土相钻井液,并对其进行了性能评价。结果表明:所研制的钻井液具有较好的抗温性能,耐温能力达160℃;具有较好的抗劣土污染能力,抗劣土污染容量限达到10%以上;润滑能力接近油基钻井液水平;岩心渗透率恢复率大于90%,具有较好的储层保护效果。由性能评价结果可以看出,该钻井液较好地解决了以往无黏土相钻井液在高温下聚合物降解造成的黏度下降问题,保证了钻井施工的安全进行,具有较好的经济效益。 

Research and Evaluation of Clay-Free Drilling Fluids with High Temperature Resistance

In order to eliminate dependence on clay by drilling fluid,overcome the degradation of conventional viscosifier and fluid loss agent at high temperature,protect reservoir and enhance penetration rate,a viscosifier or fluid loss agent called SSDP was synthesized by the sulfonic acid groups and cationic monomer,and on the basis of it,the anti-high temperature and water based clay-free drilling fluid was developed by selecting and compounding the viscosifiers,filtrate reducers,lubricants and anti-sloughing agent.The laboratory evaluation showed that the clay-free drilling fluid has better resistance to high temperature up to 160 ℃,has good resistance to unconsolidated rocks with the content of 10% or more;its lubrication peformance is close to that of oil-based drilling fluid;permeability recovery of polluted cores has reached to 90%,and shown its good reservoir protection effect.It could be seen that this drilling fluid can solve the problem of viscosity decrease caused by polymer degradation at high temperature,maintain safety and provide improved economic benefits in drilling engineering.