Thermodynamic Modelling and Parametric Study of a Two Stage Compression-Absorption Refrigeration System for Ice Cream Hardening Plant

The present communication introduces a new concept of Two Stage Vapor Compression-Absorption Cascade Refrigeration System (TSVCACRS) for achieving low temperature industrial cooling. The system comprises of Two Stage Vapor Compression Refrigeration System (TSVCRS) having flash intercooler integrated with single stage Vapor Absorption Refrigeration System (VARS); thermally coupled by means of cascade condenser heat exchanger. The cascade condenser heat exchanger works as an evaporator for VARS and the condenser for TSVCRS. The proposed system has been designed and simulated for Havmor Ice cream Limited located at GIDC, Naroda, Ahmedabad; to check the thermodynamic performance feasibility with their existing installed TSVCRS based ice cream hardening refrigeration plant of 525 TR (1850 kW). Ammonia and LiBr-H2O have been considered as working fluid pair in proposed TSVCACRS. The results show that proposed TSVCACRS system would minimize the compressor work up to 28%, compared to an existing installed TSVCRS. The exergetic efficiency of the VAR, VCR subsystems and integrated TSVCACRS is found to be 32.78%, 60.29% and 53.59%, respectively. Moreover, the optimum generator temperature for the proposed system is found to be 85 °C from the energetic and exergetic point of view.