Scrutiny of the Mechanical Vapor Recompression Crystallizer Optimization for the Aim of Zero Liquid Discharge Desalination

Over the past few decades, discussion over the environmental impact of brine disposal of desalination systems has given rise to the growing method of zero-liquid discharge desalination. This paper has been premised on the mathematical model of a single-effect force circulation crystallizer, where mechanical vapor recompression was used to bring about zero liquid discharge desalination. The objective of this validated model is to investigate the effect of rising temperature in the evaporator (۲-۴.۵ °C), evaporation, and condensation temperature difference (۵-۱۵ °C) and evaporation pressure (۲۰-۱۰۰ bar) on the power consumption of the compressor and circulation pump, the preheater and the evaporator heat-transfer area. Further, the effect of evaporation pressure on saturation salinity, boiling point elevation, and optimization of the circulation pump, the distinctive feature in the current study, was explored. It came to light that the increase in evaporation pressure has led to a reduction in total power consumption (۱۱%-۱۵%) and a lower total heat-transfer area (generally ۱۳%). Also, the optimization of the circulation pump engendered optimum rises in temperature in the evaporator per evaporation and condensation temperature difference. The results of this study provided a basis for exergoeconomic analysis which will lead to an even more optimized system.

کلیدواژه ها:

Energy Efficiency ، Mechanical vapor recompression ، Seawater ، zero liquid discharge