基于蒸汽压缩技术的热泵蒸汽系统热力性能分析

热泵蒸汽技术相比电锅炉及燃煤、燃气锅炉制取蒸汽，具有更高的一次能源利用效率，并且不产生CO₂和NO_x，符合我国节能环保发展战略。本文提出一种基于蒸汽压缩技术的热泵蒸汽系统，采用两级冷凝直接制取低压蒸汽，再通过蒸汽压缩升压至0.7MPa。并基于EES软件建立数值模型，分析冷凝温度T_cond、蒸发温度T_evap、经济器温度T_econ、喷气率β_g对冷媒压缩机功耗W_refri、蒸汽压缩机功耗W_vapor和系统能效系数COP的影响。结果如下：基于蒸汽压缩的热泵蒸汽系统，制取165℃的饱和蒸汽，在T_evap为50℃、T_cond为93℃时，系统COP为2.996，制取1t蒸汽消耗功率仅为247kW·h；系统COP随T_evap的升高逐渐增大，但是T_evap的升高需要更高的热源温度；蒸发温度不变时，系统存在最佳的T_cond、中间冷却温度T_econ和喷气率β_g，当蒸发温度T_evap为50℃，最佳冷凝温度T_cond为93℃时，最佳经济器温度T_econ为65℃，最佳喷气率β_g为0.13。

Performance analysis of heat pump steam system based on vapor compression technology

Heat pump steam technology has higher primary energy utilization efficiency, and does not produce CO₂ and NO_x, compared with electric boilers, coal-fired boilers and gas-fired boilers, which are in line with China’s energy-saving and environmental protection development strategy. This paper presented a heat pump steam engine based on vapor compression technology, which produced low pressure vapor by two-stage condensation and then boost to 0.7MPa by using vapor compressor. A mathematical model has been developed using the EES software. The effects of condensation temperature (T_cond), economizer temperature (T_econ), evaporation temperature (T_evap) on the refrigerant compressor power consumption (W_refc), vapor compressor power consumption (W_vapc), the coefficient of performance (COP) were studied in detail. The results showed that the heat pump steam engine based on vapor compression technology obtain a COP of 2.996 under T_evap is 50℃ and T_cond is 93℃. The power consumption is 247kW·h for producing 1ton saturated steam of 165℃. The COP increases gradually with the increase of T_evap, but it requires a higher temperature heat source. There exists a highest COP with the optimum T_cond, T_econ, β_g, when T_evap is 50℃, they are 93℃, 65℃ and 0.13, respectively.