Thermodynamic analysis of ammonia-water power/chilling cogeneration cycle with low-grade waste heat
Thermodynamic analysis of ammonia-water power/chilling cogeneration cycle with low-grade waste heat
复制标题
低品位余热氨水动力/冷冻联产循环热力学分析
DOI：
10.1016/j.applthermaleng.2013.12.043
复制
发表时间：
2014-03-01
影响因子：
6.4
通讯作者：
Roskilly, A. P.
中科院分区：
文献类型：
--
作者：
Hua, Junye;Chen, Yaping;Roskilly, A. P.
对利用中低品位余热发电的氨水吸收循环进行了分析和优化，该循环是一种改进的卡利纳循环，增加了蒸发器和过冷器，实现了制冷效果。该循环通过适当的内部回热过程产生制冷输出，而不消耗额外的热资源，并通过为可变相变过程实现合适的氨浓度的换热来匹配热源和冷却水，从而实现了更高的效率。分析了系统关键参数对热效率和火用效率的影响。结果表明，为了获得较高的效率，存在匹配的基本浓度和工作浓度对。较小的循环倍数和较大的激冷分数有利于提高效率，但分别受到换热器的换热约束和需求的制约。汽轮机进口参数设定为195℃/2.736 Mpa，冷却水入口温度设定为25℃，激冷分数为0.5时，热效率和(火用)效率分别达到16.4%和48.3%，比相同条件下氨水动力循环的热效率和(火用)效率分别提高24.24%和8.16%。(C)2013爱思唯尔有限公司。保留所有权利。
An ammonia-water absorption cycle for power and chilling output cogeneration from mid/low-grade waste heat was analyzed and optimized, which is a modified Kalina cycle adding an evaporator and a subcooler to realize the chilling effect. The cycle achieves higher efficiency by generating chilling output from proper internal recuperation process without consumption of additional heat resource and by realizing heat transfer with suitable ammonia concentrations for variable phase change processes to match both heat source and cooling water. Analysis of the impact of key parameters for the system on the thermal and exergy efficiencies was carried out. The results show that there are matching basic and work concentration pairs for a higher efficiency. The smaller circulation multiple and greater chilling fraction are favorable to the efficiencies but restricted respectively by heat transfer constraint of recuperator and the demand. The calculation example with the turbine inlet parameters set at 195 degrees C/2.736 MPa and the cooling water inlet temperature set at 25 degrees C with chilling fraction of 0.5 shows that the thermal efficiency and exergy efficiency reach up to 16.4% and 48.3%, about 24.24% and 8.16% higher than those of an ammonia-water power cycle under identical condition. (C) 2013 Elsevier Ltd. All rights reserved.