A heat pump in a countercurrent crystallization process

Abstract

Recently industrial heat pumps are being used as important heat recovery equipment that can facilitate energy savings in various chemical processes, like distillation, evaporation, and absorption. One of the prospective processes for the use of heat pumps is in various crystallization processes, where usually two different cooling and heating zones are present. This work presents a study of the possibility to reduce the consumption of energy in countercurrent crystallization process, which is usually used to separate organic compounds from their mixture, by introducing a heat pump with external medium (refrigeration cycle) to the process. Focus is made on a refrigeration cycle in which ammonia is used as refrigerant. Calculation for the proposed heat pump is performed. A dimensionless energy saving factor is introduced. The saving factor assumes the value of zero for conventional system. An economic analysis is made and a noticeable save in energy ranging from 34% to 45% was obtained. The effect of the feed temperature and concentration on obtained saving energy factor were investigated.