回收循环水余热的热泵供热系统热力性能分析  

Thermodynamic Analysis of Heat Pump Heating Supply Systems With Circulating Water Heat Recovery

作　　者：张学镭[1] 陈海平[1] 

机构地区：[1]华北电力大学能源动力和机械工程学院,河北省保定市071003

出　　处：《中国电机工程学报》2013年第8期1-8,15,共8页Proceedings of the CSEE

基　　金：中央高校基本科研业务费专项资金资助(09MG34)~~

摘　　要：利用吸收式热泵回收循环水余热,能够实现能量的梯级利用。以某300MW调节抽汽式汽轮机及其供热系统为例,研究回收循环水余热的热泵供热系统的可行性及各关键部件的数学模型,计算其设计工况和变工况性能,对热泵供热方式进行了热力性能评价。结果表明,设计工况下,热泵性能系数为1.706,热泵供热方式的火用效率比传统供热方式提高了11.17个百分点,机组功率增加4.63MW;冷凝器出口热网水温度的升高使热泵性能系数下降,但热泵供热方式火用效率逐渐增加;热网返回水温的降低使热泵性能系数升高,但热泵供热方式火用效率呈先增大后减小的趋势;蒸发器出口循环水温度的升高或蒸发器内循环水温降的减小均使热泵性能系数、机组功率增加量和热泵供热方式火用效率增大。回收循环水余热的热泵供热方式具有良好的热力性能和社会效益。Heat recovery from circulating water based on absorption heat pump can achieve the energy cascade utilization. Take a certain 300MW regulated extraction steam turbine as an example, this paper studied the feasibility of heat pump heating supply system （HPHSS） with circulating water heat recovery. The thermodynamic model, which considered the influence of heat recovery on condenser vacuum, was proposed to simulate the HPHSS design and off-design performance from the perspective of the overall system. The results indicate that at design condition, the heat pump coefficient of performance （COP） is 1.706, and HPHSS increases exergy efficient by 11.17 percentage points and increases the unit output power by 4.63 MW compared to traditional mode. With the increase in condenser outlet heating network water temperature, it declines the heat pump COP, but increases HPHSS exergy efficient gradually. With the reduction of return water temperature, it increases the heat pump COP, but increases firstly and then decreases HPHSS exergy efficient. Enhancing the evaporator outlet temperature of circulating water or reducing the circulating water temperature drop in the evaporator increase heat pump COP, unit output power and HPHSS exergy efficient. HPHSS with circulating water heat recovery possesses the good thermodynamic performance and social benefits.

关 键 词：热泵 循环水 余热利用 热力性能 供热系统 

分 类 号：TK264[动力工程及工程热物理—动力机械及工程]