地热闪蒸-双工质联合发电系统最佳参数选择

Optimal Parameter Selection of Geothermal Flash-binary Power System

介绍了地热闪蒸-双工质联合发电方式,通过数学模拟,分析地热水温度对单位热水发电量、热效率和最佳温度的影响,计算结果表明,地热水温度为80℃时,闪蒸系统采用直接冷却和间接冷却方式的联合发电系统的单位热水净发电量分别为1.08和0.86kW·h/t,地热水温度为150℃时,闪蒸系统采用直接冷却和间接冷却方式的联合发电系统的单位热水净发电量分别为6.57和6.35kW·h/t;采用直接冷却方式的联合发电系统的发电量以闪蒸发电为主,采用间接冷却方式的联合发电系统的发电量以双工质发电为主;当热源温度为100、130和150℃时,采用直接冷却和间接冷却方式的联合系统的最佳温度分别为80和85℃、100和115℃、125和140℃。地热闪蒸-双工质联合发电技术可以为中国中低温地热资源开发提供技术支撑。

The flash-binary system includes the single flash power system and the binary cycle system. The flash-binary power system enhances the production as compared with the single flash power system. In addition, compared with the two-stage flash power system, the single flash-binary power system can avoid some problems, such as the bulky equipments, the difficult installment and the high cost. Based on the numerical simulation, the effect of the geothermal water temperature on the net power output, the thermal efficiency and the optimal temperature of the flash-binary power system are discussed in this paper. The simulation results show that, when the temperature is 80℃, the net power output per geofluid is about 1.08 and 0.86kW-h/t by the direct cooling and the indirect cooling of the flash system, respectively; when the temperature is 150℃, the values are 6.57 and 6.35kW.h/t; when the geothermal water temperatures are 100, 130 and 150℃, the optimal temperatures of the combined system are 80 and 85℃, 100 and 115℃, 125 and 140℃ by the direct cooling and the indirect cooling of the flash system, respectively. In addition, the power output of the flash-binary system by the direct cooling is dominated by the flash power generation, while that by the indirect cooling is dominated by the binary power generation. The flash-binary power system could provide a technical support for the geothermal resource utilization in China.