Working fluids of a low-temperature geothermally-powered Rankine cycle for combined power and heat generation system

作者：Guo Tao; Wang HuaiXin; Zhang ShengJun

来源：Science in China - Series E: Technological Sciences , 2010, 53(11): 3072-3078.

DOI：10.1007/s11431-010-4102-5

• organic Rankine cycle (ORC)
• low-temperature geothermal
• working fluids
• power generation
• heat production
• heat pump

A novel combined power and heat generation system was investigated in this study. This system consists of a low-temperature geothermally-powered organic Rankine cycle (ORC) subsystem, an intermediate heat exchanger and a commercial R134a-based heat pump subsystem. The advantages of the novel combined power and heat generation system are free of using additional cooling water circling system for the power generation subsystem as well as maximizing the use of thermal energy in the low-temperature geothermal source. The main purpose is to identify suitable working fluids (wet, isentropic and dry fluids) which may yield high PPR (the ratio of power produced by the power generation subsystem to power consumed by the heat pump subsystem) value and QQR (the ratio of heat supplied to the user to heat produced by the geothermal source) value. Parameters under investigation were evaporating temperature, PPR value and QQR value. Results indicate that there exits an optimum evaporating temperature to maximize the PPR value and minimize the QQR value at the same time for individual fluid. And dry fluids show higher PPR values but lower QQR values. NH3 and R152a outstand among wet fluids. R134a outstands among isentropic fluids. R236ea, R245ca, R245fa, R600 and R600a outstand among dry fluids. R236ea shows the highest PPR value among the recommended fluids.

• 出版日期2010-11
• 单位天津大学