The largest geothermal storage and refill project of surface water in China was recently completed and put into operation in Dongli Lake, which realizes its goal of storing geothermal resources in summer for use in winter. This project has also developed a new path for the sustainable development and utilization of geothermal resources.
The geothermal storage and refill project of surface water [Photo/tjdl.net]
Unlike the previous method of collecting geothermal resources, the underground water flows back to the ground after the thermal energy exchange. This project takes advantage of the abundant surface water resources of Dongli Lake in summer, injecting the water into the underground thermal reservoir after special treatment so as to achieve the "sponge city" effect and sustainable development of geothermal resources by increasing the pressure of underground thermal energy storage and enhancing the reserves of geothermal resources.
According to the refill amount of 1.2 million cubic meters of water, 600,000 cubic meters of geothermal resources will be increased every year. The amount of heat generated is equivalent to the amount generated by 11,000 tons of standard coal every year. About 28,000 tons of carbon dioxide, sulfur dioxide, nitrogen oxides and suspended particles will be reduced.
The special treatment of the water is the determinant of geothermal storage and refill project of surface water. Therefore, the scientific research team systematically analyzed the hydrogeological conditions, underground structural characteristics, water hardness, and the content of organic substances in the surface water of Dongli Lake.
At present, the geothermal heating generated from Dongli Lake area accounts for half of the total heat supply in Dongli district.