The project of reinjecting the geothermal reservoir of Wumishan Formation in Jixian System with the surface water of Dongli Lake

Reinjecting the geothermal reservoir with allogenic water during the non-heating period can effectively alleviate the pressure drop of the thermal reservoir and realize the sustainable utilization of geothermal resources. In the Dongli Lake area of Tianjin, the development and utilization of geothermal resources are concentrated and have relatively abundant surface water resources, which are the necessary conditions for surface water to reinject the thermal reservoir. This project drilled three geothermal reinjection wells, formulated the surface reinjection process, built the reinjection station, installed the monitoring system, carried out the reinjection experiments, and so on. This project used Dongli Lake water to reinject the thermal reservoir of Wumishan Formation of Jixian System. It can meet the requirements of 450 m³ /h reinjection water quality treatment, and the cost is 2.26 yuan/m³. During the operation, the water quantity and quality of the produced water were stable which met the requirements of reinjection. This project provides a new idea for the supply of geothermal reservoirs by allogenic water and opens up a new direction for the protection of geothermal resources. It can provide a demonstration for the construction of similar surface water reinjection projects whose development prospects is broad. It ensures the sustainable utilization of geothermal resources, so as to effectively develop new productivity and help achieve the ‘double carbon goal’.