偏高岭土矿渣地聚合物固井水泥浆体系研究

Research on metakaolin-slag geopolymer cementing cement slurry system

地聚合物比现有的油井水泥性能优越,是常规固井水泥的替代品,但是目前没有成熟的地聚合物固井水泥浆体系。为了研发出一套成熟的地聚合物固井水泥浆体系,针对地聚合物在配比设计和制备理论不成熟的问题,开展了碱激发剂(氢氧化钠与速溶硅酸钠)和原材料偏高岭土与矿渣的配比对地聚合物抗压强度的影响等方面的研究工作,优选出地聚合物碱激发剂及最优配比。结果表明复配NaOH和速溶硅酸钠作碱激发剂比NaOH或速溶硅酸钠单独作碱激发剂对地聚合物抗压强度的影响大,原材料偏高岭土和矿渣的质量比不同也影响地聚合物的抗压强度。当选用5%NaOH与5%速溶硅酸钠作碱激发剂,偏高岭土和矿渣的质量比为2∶8时,制备到的偏高岭土矿渣地聚合物抗压强度最佳,在自然条件下养护3天后抗压强度可达到28.68 MPa。以上成果认识,对地聚合物应用于井下固井具有一定的指导意义。

Geopolymer cements are superior to existing well cements and are an alternative to conventional cementing cements,but there is no mature cementing slurry system.The project uses the controlled single variable method and orthogonal experiment design to explore the influence of the ratio of alkali activator(sodium hydroxide and instant sodium silicate)and raw material metakaolin to slag on the compressive strength of geopolymers,and the geopolymer is optimized.Alkali stimulant and optimal ratio.The results show that when 5%NaOH and 5%instant sodium silicate are selected as the alkali activator and the mass ratio of metakaolin to slag is 2∶8,the prepared metakaolin-slag geopolymer has the best compressive strength.After curing for three days,the compressive strength can reach 28.68 MPa.The understanding of the above results has a certain guiding significance for the application of geopolymer in underground cementing.