Energy and Exergy Analysis of Condensate and Vapor Management System: A Case Study of Urmia Sugar Plant

The sugar production industry represents one of the most energy-demanding processing sectors within agro-industry systems, characterized by substantial energy inputs and large-scale operations. Given the importance of sustainability of food production systems, environmental issues, limited fossil fuel reserves, and the reduction of the share of energy in the final price of the product, a detailed assessment of sugar production processes is required. In this study, vapor recovery and vapor condensation units were evaluated by thermodynamic analyses. Energy losses and thermodynamic inefficiencies in each subsystem were determined using energy and exergy analyses. The results of the analyses showed that from an energetic and exergetic perspective, the vapor condensation unit has a much weaker thermodynamic performance than the vapor recovery unit. The exergy destruction rate and improvement potential of the vapor condensation unit were 6.90 and 47.79 times that of the vapor recovery unit, respectively. Also, the sustainability index and exergy efficiency of the vapor recovery unit were 7.11 and 238.69 times that of the vapor condensation unit, respectively. In the vapor condensation unit, the highest amount of exergy destruction, the lowest exergy efficiency, the lowest sustainability index and the highest improvement potential belong to the cooling tower, respectively, with 1073.91kW (equivalent to 33.52% of the total exergy destruction), 2.93%, 1.03 and 1042.48kW. It is suggested that the vapor of the last effect of the evaporation line and the crystallization process be regenerated using mechanical and thermal compression methods in order to reduce the vapor entering the vapor condensation unit and consequently reduce the exergy destruction to use it in syrup heating processes.