The impact of diatomite on the performance of geothermal cement in shallow and middle layers
JI Ying
LIU Shibin
XUE Yuze
LIU Baolin
SONG Li
SU Huxiong
WU Jiarui
Abstract：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 SiO2 and cement have low thermal conductivity.
Keywords：geothermal wellscement specimenthermal conductivityporositycompressive strengthcorrosion resistance
Publication Date：2026-01-25
Online Publishing Date：2026-03-17(First online date of this platform, not the publication date of the document)
Pages：6( 53-58 )