【摘要】 本文在单效低温浓缩碱液热泵系统的基础上,建立一种双效低温浓缩碱液热泵系统。通过模拟计算,研究了碱液浓缩蒸发压力对双效系统性能的影响,并在相同的碱液浓缩环境与目标下,对比了双效系统与单效系统的性能。结果表明:双效系统单位能耗蒸发量(Specific Moisture Extraction Rate,SMER)随着一效碱液浓缩蒸发压力的升高而降低,随着二效碱液浓缩蒸发压力的升高而升高;压缩机压比r随着一效碱液浓缩蒸发压力的升高而升高,随着二效碱液浓缩蒸发压力的升高而降低,且SMER的范围为13.87～19.55,r的范围为2.003～2.541;当一效和二效碱液浓缩蒸发压力分别取7.5 kPa和6.5 kPa,双效系统SMER最高达到19.55;在相同的压力变化范围内,单效系统压缩机压比r在1.7～1.75之间,SMER近似为13.7,均低于双效系统;采用双效技术解决了单效系统中存在的压缩机压比过小的问题,且双效系统SMER高于单效系统,热能得到进一步回收。更多还原

【Abstract】 Based on the present study, a new heat pump system for double-effect hypothermia evaporation concentrating Na OH solution is constructed in this paper. The influence of lye evaporation pressure on the performance of the double-effect system is studied, and the performances of the double-effect system and the single-effect system under the same NaOH concentration environment and target are compared through simulation. The simulation results show that, the specific moisture extraction rate(SMER) of double-effect system is decreased with the increase of the first effect lye evaporation pressure, and is increased with the increase of the second effect lye evaporation pressure; the value ranges from 13.87 to 19.55; the pressure ratio of compressor of double-effect system is increased with the increase of the first effect lye evaporation pressure, and is decreased with the increase of the second effect lye evaporation pressure; the value ranges from 2.003 to 2.541; the SMER of double-effect system gets to the highest value as 19.55 when the concentration evaporation pressure of first and second effect lye was 7.5 k Pa and 6.5 kPa; in the same range of pressure change, the SMER of single-effect system maintains around 13.7, and the pressure ratio of compressor in single-effect system is between 1.7 and 1.75, which are lower than those of double-effect system; the double-effect technology solves the problem that the pressure ratio of compressor in the single-effect system is too small, and the SMER of double-effect system is higher than that of the single-effect system, which means the heat energy is further recovered.更多还原