耦合CO_(2)脱气的岩溶地热水结垢趋势定量分析  

Quantitative analysis of scaling tendency of karstic geothermal water coupled with CO_(2)degassing

作　　者：吕良华 王水[1,3] LÜLianghua;WANG Shui(Jiangsu Provincial Key Laboratory of Environmental Engineering,Jiangsu Provincial Academy of Environmental Science,Nanjing 210036,China;Nanjing Hydraulic Research Institute,Nanjing 210029,China;Jiangsu Province Engineering Research Center of Soil and Groundwater Pollution Prevention and Control,Nanjing 210036,China)

机构地区：[1]江苏省环境科学研究院江苏省环境工程重点实验室,江苏南京210036 [2]南京水利科学研究院,江苏南京210029 [3]江苏省土壤与地下水污染防控工程研究中心,江苏南京210036

出　　处：《地学前缘》2024年第3期402-409,共8页Earth Science Frontiers

基　　金：国家自然科学基金项目(42202281);江苏省卓越博士后计划项目(2023ZB141)。

摘　　要：岩溶地热系统是最具开发潜力的水热型地热系统之一,在水热型地热资源利用中,地热水结垢(尤其是井下结垢)是目前面临的最普遍、最重要的问题之一,制约着地热水资源可持续利用。针对岩溶地热水结垢趋势分析方法存在的不足,在重点考虑CO_(2)脱气这一重要过程对结垢趋势影响的基础上,利用化学热力学模拟技术构建了一种耦合CO_(2)脱气过程的结垢趋势定量分析的改进方法,并将其应用于南京汤山岩溶地热区。结果表明汤山地区地热水不具有发生SiO 2结垢的趋势;在井口有发生碳酸盐结垢趋势,主要成分为CaCO_(3);井筒中下部有发生不同程度的硫酸盐结垢趋势,主要成分为CaSO_(4),SrSO_(4),BaSO_(4)。本研究在改进结垢趋势分析方法不足的同时,为防垢除垢工作提供了理论基础和方法指导,可有力促进地热水资源的可持续利用。Low-to-medium temperature fluid reservoirs hosted in carbonate rocks represent a promising yet relatively unknown hydrothermal geothermal system.Scaling of geothermal water,particularly underground scaling,poses a significant challenge in the sustainable utilization of geothermal resources.To address the limitations of current methods for analyzing karstic geothermal water scaling trends,a chemical thermodynamic simulation approach was employed to develop an enhanced method for quantitatively assessing scaling trends in geothermal water,considering CO_(2)degassing effects.This study focused on the influence of CO_(2)degassing on scaling trends.The scaling tendency of the Tangshan karstic geothermal area in Nanjing was quantitatively analyzed using the improved method.Results indicate that the geothermal water in the Tangshan area exhibits a propensity for carbonate scaling at the wellhead,primarily composed of CaCO_(3),and varying degrees of sulfate scaling in the middle and lower sections of the wellbore,with main components including CaSO_(4),SrSO_(4),and BaSO_(4).By addressing the limitations of existing scaling trend analysis methods,this study offers a theoretical foundation and methodological guidance for scale prevention and removal,thereby facilitating the sustainable utilization of geothermal water resources.

关 键 词：岩溶地热水 可持续利用 结垢趋势分析 CO_(2)脱气 地球化学模拟 汤山 

分 类 号：P641[天文地球—地质矿产勘探]