摘要
增强型地热系统(EGS)是通过人工形成地热储层而从低渗透性岩体中经济地采出热能的地热系统。为了提高热储层的渗透率,需要对热储层实施化学刺激,增加深部岩体中地热能的采收率。以采自青海共和盆地的花岗岩样品(与盆地基底干热岩体的岩性相同)为研究对象,选用10%HCl+3%HF的土酸为化学刺激剂,在不同温度和试验时间反应条件下开展了花岗岩化学刺激试验,研究了土酸化学刺激剂对实际EGS储层的化学刺激效果以及溶蚀特征。结果表明:土酸刺激后花岗岩的渗透率明显提高,且其渗透率的提高倍数随温度的升高和时间的延长而增大;化学刺激试验中发现花岗岩化学组成中石英和长石发生溶蚀,而且还生成了氟铝酸钾、氟硅酸钾和石英蚀变矿物。
The Enhanced Geothermal System（EGS）is a geothermal system to extract thermal energy at a low cost from low-permeability rock mass through artificial geothermal reservoir.To enhance the permeability of reservoir,chemical stimulation techniques are applied to increase the recovery efficiency of geothermal energy in deep rocks.This paper focuses on the granite rock samples collected from Gonghe basin in Qinghai province（the lithology is the same with that in the basement of the basin）,and conducts the chemical stimulation experiments with different reaction temperatures and time by choosing 10% HCl＋3% HF acid as the chemical stimulus.The paper mainly studies the chemical stimulation effect of the mud acid on the EGS reservoir and the reservoir＇s corrosion characteristics.The results show that the rock permeability is improved significantly with the stimulation of mud acid,and the magnification is increased as the temperature and time increase.In the experiment,the quartz and feldspar are corroded,with the formation of some altered minerals such as quartz,aluminum acid potassium fluoride,and potassium fluosilicate.
作者
庄亚芹
张灿海
朱明成
朱永强
骆进
郭清海
ZHUANG Yaqin ZHANG Canhai ZHU Mingcheng ZHU Yongqiang LUO Jin GUO Qinghai(School of Environmental Studies, China University of Geosciences , Wuhan 430074, China Huanghe Hydropower Development Co. ,Ltd. ,State Power Investment Corporation, Xining 810008, China Faculty of Engineering, China University of Geosciences Wuhan 430074, China)
出处
《安全与环境工程》
CAS
2017年第2期16-21,45,共7页
Safety and Environmental Engineering
基金
国家自然科学基金项目(41572335)
国家电力投资集团公司科技项目(2015-138-HHS-KJ-X)
关键词
增强型地热系统
花岗岩渗透率
土酸
化学刺激试验
储层改造
Enhanced Geothermal System（EGS）
granite rock permeability
mud acid
chemical stimulation experiment
reservoir reform
