高效利用地热资源已成为地热开发利用的焦点话题,中国地热资源丰富,但大多分布偏远,地热资源利用率总体较低。本文结合国内外地热利用现状及发展趋势,重点阐述以氨水作为工质的动力循环系统,提出了净功率、电力产率、热效率和换热面积比率的性能指标,并分析氨水溶液质量分数、循环倍率和热水温度对上述指标的影响。在此基础上,探讨了建设适合于华南地域特征的地热资源综合梯级利用示范项目,实现资源利用率达到70%以上,为中低温余热利用提出了一个新的途径。

It becomes a hot topic that geothermal resources are effectively utilized; there is rich geothermal resource located in the remote areas in China. Based on the situation and development trend of geothermal utilization, the ammonia water power cycle is introduced and the cycle performance criteria, such as net power output, net power energy per ton of geothermal water, heat efficiency, and heat exchanger area of per net power, are presented. In addition, a demonstration project of geothermal resource cascade utilization in south China area is discussed, the resource utilization rate is more than 70%. The results indicate that AWPC cycling performance could be changed by adjusting the mass fraction of the ammonia solution, a higher ammonia mass fraction solution is favorable for protecting the system from the negative pressure, and the higher mass fraction is, the higher pressure is. There is an optimal circulation ratio in AWPC system, the value is about four for the mid-low temperature geothermal resource and the corresponding mass fraction difference between concentrated solution and dilute solution is about 12%—13%. The mode exploits a new way for efficiently utilizing the mid-low temperature geothermal resource.