地热井高导热低密度固井材料制备、性能及结构  

Preparation Properties and Structure of High Heat Conduction and Low Density Cementing Materials for Geothermal Wells

作　　者：杨雨 徐拴海 张浩 韩永亮 张卫东 李永强 YANG Yu;XU Shuanhai;ZHANG Hao;HAN Yongliang;ZHANG Weidong;LI Yongqiang(China Coal Research Institute,Beijing 100013;China Coal Technology&Engineering Group Xi’an Research Institute,Xi’an,shaanxi 710077)

机构地区：[1]煤炭科学研究总院,北京100013 [2]中煤科工集团西安研究院有限公司,西安710077

出　　处：《钻井液与完井液》2021年第1期93-101,共9页Drilling Fluid & Completion Fluid

基　　金：地科技股份有限公司科技创新资金专项项目“基于定向井的中深层地热开发利用关键技术研究与试验工程”(2018-TD-ZD017)。

摘　　要：高导热低密度固井材料(HLC)能够有效解决中深层地热井井深易漏的固井难题,并能有效提高地热井地下换热效率。通过正交实验,基于层次分析法和矩阵分析法,综合考虑导热系数、48 h抗压强度、密度和成本4个指标,制备了可用于中深层地热井固井的HLC;通过实验测试了固井材料的各性能指标;利用SEM、XRD和MIP观测了HLC的微观结构,并分析了导热机理。结果表明,HLC配方为:55%水泥+9%石墨+25%石英粉+2%粉煤灰+2%硅灰+2%降失水剂+3%稳定剂+1.5%膨胀剂+0.5%缓凝剂,W/C=0.78;其各项性能指标均满足相关规范要求;石墨的加入改善了HLC的微观结构及孔径分布;导热机理符合导热路径理论。可为中深层地热井的固井施工和相似材料的制备研究提供借鉴。High heat conduction and low density cementing material(HLC)can effectively solve the cementing problem of deep and easy to leak geothermal wells,and can effectively improve the underground heat transfer efficiency of geothermal wells.Through orthogonal test,based on analytic hierarchy process(AHP)and matrix analysis,and considering four indexes of thermal conductivity,48 h compressive strength,density and cost,the HLC which can be used for cementing of deep geothermal well was prepared.The performance indexes of cementing materials were tested by experiments.The microstructure of HLC was observed by SEM,XRD and MIP,and the mechanism of heat conduction was analyzed.The results show that the HLC formula is:0.78 water solid ratio,55%cement,9%graphite,25%quartz powder,2%fly ash,2%silica fume,2%fluid loss additive,3%stabilizer,1.5%expansion agent and 0.5%retarder;its performance indexes meet the requirements of relevant specifications;the addition of graphite improves the microstructure and pore size distribution of HLC;the heat conduction mechanism conforms to the heat conduction path theory.It can be used for reference for cementing construction and preparation of similar materials in deep geothermal wells.

关 键 词：地热能 高导热低密度固井材料 导热系数 层次分析法 矩阵分析法 微观结构 

分 类 号：TE256.6[石油与天然气工程—油气井工程]