摘要
通过对湖南汤市地热田浅层地下水、常温地下水以及地热水化学特征分析,运用Phreeqc模拟软件对地热系统中水-岩作用过程进行模拟.根据质量平衡模型原理计算出从"初始水质"到"终点水质"2条模拟路线上各矿物的饱和指数及溶解(沉淀)量,推测地热水化学形成过程中组分和质量转移情况,模拟结果表明此过程中钠长石、钾长石、方解石、萤石、黄铁矿、二氧化碳产生溶解,石英、高岭石、白云石产生沉淀;地热水与热储中的矿物通常处于平衡状态,这种平衡信息可由热水的化学成分反映出来。根据地热水的水质分析结果运用组分分布模型原理计算出地热水中各矿物的饱和指数,并把热水中多种矿物的饱和指数作为温度的函数绘图,据此推断出热储的平衡矿物及热储温度,模拟结果表明热储形成温度在70~125℃之间.
Through analyzing the chemical character of the shallow groundwater in the geothermal field,the normal temperature of groundwater and geothermal water,this paper applies the Phreeqc simulation software to simulate water-rock interaction process in the geothermal system. It calculates the mineral saturation indices and dissolved quantity in the two motion path simulations,ranging from the initial water quality to the end,based on the principle of mass balance model. It also predicts the components and mass transformation in geothermal water chemical formation process. The simulation results show that this process of sodium feldspar,potassium feldspar,calcite,fluorite,pyrite,and CO2 is dissolved,while the chalcedony,kaolinite,and dolomite is in precipitation.The mineral in thermal storage and geothermal water is always in a balanced state,which is reflected by the chemical component of geothermal water. It infers the balance of mineral and the temperature of thermal storage according to the water quality analysis results and the saturation index,based on the principle component distribution model. In the process,function plotting of the mineral saturation index of geothermal also plays an important role. The simulation results show that the formation temperature of heat reservoir is between 70 ~125 ℃.
作者
焦春春
肖江
皮建高
孙锡良
Jiao Chunchun;Xiao Jiang;Pi Jiangao;Sun Xiliang(School of Resource Environment and Safety Engineering,Hunan University of Science and Technology,Xiangtan 411201;402 Geological Brigade,Hunan Geology and Mineral Exploration Bureau,Changsha 410000,China)
出处
《矿业工程研究》
2018年第1期49-53,共5页
Mineral Engineering Research
基金
湖南省研究生科研创新资助项目(CX2016B569)
