摘要
天津是我国较早大规模开发深层地热的地区之一,经过30多年的持续开采回灌,对深部热储特征有无影响,是否引起了资源枯竭、水质恶化以及热储温度下降等环境问题,一直是社会关注的焦点。本文系统收集了1992年以来天津市地热开发过程中的不同热储层热水开发利用量、回灌量、水位、水质、水温等近30年的时间序列监测资料,通过垂向及横向对比,对地热持续开发30年来天津市不同地区不同热储层的热水动态特征进行了分析。结果表明,天津市各热储层地热流体的主要化学组分基本稳定,多年来无明显变化,地热采灌系统尾水回灌不会从根本上改变地热流体的原始化学特征,但深大断裂作为热流通道引起的顶托补给,会对上层热储水质造成一定的影响;随着近年来天津市回灌工作力度不断加大,大部分热储水位下降幅度减缓或出现回升,热储的温度没有明显的升高或降低的趋势,但回灌井热储段经过非供暖期的恢复无法达到最初的温度,呈逐年下降趋势。未来持续采灌条件下,回灌井筒的“冷堆积”及采灌井的优化调配应是重点关注的问题。
Tianjin is one of the early areas of large-scale development of deep geothermal reservoirs in China.After more than 30 years of continuous exploitation and recharge,whether there is any impact on deep geothermal reservoirs and whether it has caused environmental problems such as resource depletion,water quality deterioration and temperature decrease of geothermal reservoirs has been the focus of social concern.In this paper,the dynamic characteristics of different geothermal reservoirs in different areas of Tianjin were analyzed through vertical and horizontal comparisons based on the systematic collection of time series monitoring data of hot water utilization,reinjection volume,water level,water quality and water temperature for nearly 30 years since 1992 in different geothermal reservoirs in Tianjin.The results show that the main chemical components of geothermal fluids in geothermal reservoirs throughout Tianjin are basically stable and have not changed significantly over the years,and reinjection in the geothermal pumping and reinjection system will not fundamentally change the original chemical characteristics of the geothermal fluids,but the leakage recharge caused by deep large fractures as heat flow channels will have some impact on the water quality of the upper geothermal reservoirs.With the increasing recharge efforts in Tianjin in recent years,the continuous decreasing trend of water level in most geothermal reservoirs has been slowed down or rebounded,and the temperature of geothermal storage has no obvious trend of increasing or decreasing,but the target layer of reinjection wells cannot reach the initial temperature after the recovery of non-heating period,and it is decreasing year by year.Under the future continuous pumping and reinjection conditions,the“cold accumulation”of reinjection wells and the optimal deployment of pumping and reinjection wells should be a key concern.
作者
殷肖肖
赵苏民
蔡芸
闫佳贤
许磊
YIN Xiaoxiao;ZHAO Sumin;CAI Yun;YAN Jiaxian;XU Lei(Tianjin Geothermal Exploration and Development Designing Institute,Tianjin 300250,China;Technology Innovation Base of Geothermal Resources Development and Utilization,Tianjin 300250,China)
出处
《地质学报》
EI
CAS
CSCD
北大核心
2024年第1期297-313,共17页
Acta Geologica Sinica
基金
天津市规划和自然资源局公益性监测项目(编号ML2022-HP-F031)资助的成果。
关键词
地热开发
水动力场
化学场
温度场
天津
geothermal resources development
hydrodynamic field
chemical field
temperature field
Tianjin
