Cycle Analysis on Optimal Intermediate Temperature of Heat Pump/MVR Coupled System for Industrial Process

In this paper, a cycle analysis was performed on a heat pump and MVR coupled system. Through a cycle analysis, the integrated COP of a heat pump/MVR coupled system was derived as a function of the temperature of the waste heat generated from the industrial process, the temperature of the steam used in the industrial process, and the intermediate temperature of the primary heating through the heat pump. Cycle analyses were performed for the use of steam in industrial process under saturation and subcooling conditions, respectively. When using steam under a saturation liquid state in an industrial process, it was found that there were optimal intermediate temperatures at which the combined COP of the heat pump/MVR system was maximized in the waste heat temperature range of 40 to 100℃ and the production steam temperature range of 165 to 210℃. On the other hand, when utilizing steam in industrial process to a subcooling region, it was found that the integrated COP decreased with increasing intermediate temperature for all waste heat and production steam temperature conditions. Based on results of this analysis, it was determined that depending on how the steam produced was utilized in the industrial process, it might be advantageous to design a heat pump/MVR combined system or o design a system with an MVR system alone.