Resreach Of Low-temperature Geothermal Water For Heating

With the development of international economy, the requirement of energy is greatly increasing while the ecological environment is deteriorating. Therefore, the development and utilization of renewable energy is becoming more and more important. As the world's most important available renewable energy, geothermal energy has an unparalleled advantage. The main application of low-temperature geothermal water is in the form of geothermal heating, but the temperature of the discharge water after heat exchanged by the heating system is hill, which causing great waste of energy. This paper tries to put forward the combine heat pump technology to improve the utilization of geothermal resources.This study based on a particular geothermal heating project, the operating parameters of the system were analyzed and the theory of graded use of geothermal water was illustrated. The result showed that, in order to improve the overall energy efficiency, the temperature of discharge water was hill, and the utilization rate of geothermal water was low. What's worse, hot discharge water will cause thermal pollution which is not conducive to environmental protection.Therefore, this paper puts forward constant flow operation, variable flow operation, boiler peaking load regulation and the mixing water strategies, system design and energy consumption analysis were considered. The result shows that, for the Low-geothermal water, the temperature of discharge water can be reduced by variable flow control, which can save geothermal water resources. But it will cause lower total system energy efficiency and higher operating costs. Boiler Peak combined geothermal energy for heating strategy is optimized at the base of the system above with, which can effectively control both the equipment costs and operating costs under decent range, however, environmental pollution must be considered. Mixing water strategy can not only reduce heat loss from plate heat exchanger, but also further reduce the temperature of discharge water, the initial cost and operating cost are controlled well. Nevertheless, the problem of heat pump evaporator corrosion rehabilitation remains to study.During this study, the author has participated in the New Energy Development of the region. And the conclusions of this paper will provide reference for the geothermal water heating system design in related area, or expanding heating area of the original system.