摘要
在地热筒井的中上层,部分地热能会通过管壁向低温地层传递,而地层的酸性环境会使水泥的耐久性降低。掺入硅藻土制备水泥试块,通过扫描电镜、压汞、导热系数测定仪,分析硅藻土水泥试块酸性环境腐蚀前后的性能。结果表明,硅藻土掺量为16%时水泥试块各龄期抗压强度较高,明显高于未掺时;掺入硅藻土,水泥试块耐腐蚀性提高;随硅藻土掺量的增加,水泥试块的导热系数明显降低,最大降幅可达26%;这是因为掺入硅藻土可细化孔隙,使孔隙分布更加均匀,且其中SiO_(2)与水泥发生火山灰反应生成的水化硅酸钙和氢氧化钙导热系数较低。
In the middle and upper sections of geothermal boreholes,a portion of geothermal energy is transferred through the casing wall to lower-temperature strata,the acidic conditions in the formation can diminish the durability of the cement.In this study,diatomite was incorporated to prepare cement specimens,and the performance changes of diatomite cement test blocks before and after corrosion in different acidic environment were analyzed using scanning electron microscopy,mercury intrusion porosimetry,and thermal conductivity measurement.The results indicate that when the diatomite content is 16%,the compressive strength of cement test blocks at various ages is higher,significantly higher than that without diatomite;the corrosion resistance of cement test blocks is improved by adding diatomite;as the diatomite content increases,the thermal conductivity of cement test blocks decreases significantly,with a maximum reduction of up to 26%.This is because the addition of diatomite can refine pores,making the pore distribution more uniform,and the hydrated calcium silicate and calcium hydroxide generated by the pozzolanic reaction between SiO_(2) and cement have low thermal conductivity.
作者
嵇鹰
刘仕滨
薛宇泽
刘保林
宋利
苏虎雄
吴佳瑞
JI Ying;LIU Shibin;XUE Yuze;LIU Baolin;SONG Li;SU Huxiong;WU Jiarui(College of Materials Science and Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,China;Shaanxi Coal Geology Group Co.Ltd.,Xi'an 710021,China;China Building Materials Industrial Construction Xi'an Engineer Co.Ltd.,Xi'an 710075,China)
出处
《新型建筑材料》
2026年第1期53-58,共6页
New Building Materials
关键词
地热井
水泥试块
导热系数
孔隙率
抗压强度
耐腐蚀性
geothermal wells
cement specimen
thermal conductivity
porosity
compressive strength
corrosion resistance
