The Exploration and Utilization Status of Geothermal Resources and Future Development in Tianjin, China

Abstract

The Exploration and Utilization Status of Geothermal Resources and Future Development in Tianjin, China Sun Yixuan China University of Geosciences, Beijing, 100083 syxxx0716@yahoo.cn Ruan Chuanxia Tianjin Geothermal Exploration and Development Designing Institute rchx12@sohu.com The exploration of geothermal resources began in 1970’s and the large scale exploration and evaluation began in 1980’s in Tianjin. There are 10 geothermal abnormal fields, including the geothermal fields of Wanglanzhuang, Shanlingzi, Wanjiamatou and so on. The total exploration area is up to 3000 km2, the largest exploration depth is 4000m. There are 8 geothermal fields had been finished in exploration, which are Wanglanzhuang Shanlingzi, Binhai, Wuqing, Panzhuang-lutai, Ninghe-hangu, Wanjiamatou and Zhouliangzhuang. The total production of geothermal resources is 7606.6× 104m3/a(more than 25 degree), the available geothermal energy is 1.30×1016 J/a which is equal to 4.43×105 t/a normal coal. Includeing a 6 layer reservoir of two kinds, Tianjin geothermal field is a typical sedimentary basin low-temperature geothermal system . According to the reservoir porosity and the motion condition of geothermal fluids, one of them is a closed clastic rock subsystem, where geothermal water is present in pores, the other is semi-open and semi-closed bedrock subsystems where the karst geothermal water is present. From the top to the bottom the reservoirs are Minghuazheu group reservoir (Nm), Guantaozu group reservoir (Ng), Dongyingzu group reservoir (Ed), Ordovician reservoir (O), Cambrian reservoir (Є) and Wumishan group reservoir (Jxw). The development and use of geothermal resources began in 1930’s with more than 80 year history. There are 349 geothermal wells (74 geothermal reinjection wells) in the end of 2011.The total production was 2976 × 104m3 and the reinjection rate was 939 × 104m3 in 2011. The main use of geothermal resources is space heating. There are 1320×104m2 space heating of geothermal resources which is 5% city space heating. Tianjin is the largest city in space heating use of geothermal resources in China. The geothermal resources are use for living hot water, bathing, spa, physical therapy, swimming pool, greenhouse and so on. In the future, there are three main aspects we need to deal with. First of them is the important work about further development exploration and evaluation of geothermal resources in order to ensure the quality of geothermal resources. Second one is the development of geothermal resources in the reinjection situation which play an significant role to study the pore reservior reinjection, maintain the reservoir pressure and ensure sustainable use. Last but not least, augue0 the use fields of geothermal resources, for example the generating electricity of low-temperature geothermal resources.