Integration of Hydrate-Based Desalination (HBD) into Multistage Flash (MSF) Desalination as a Precursor: An Alternative Solution to Enhance MSF Performance and Distillate Production

Abstract

This study considers the integration of multistage flash (MSF) desalination with hydrate-based desalination (HBD) precursor to improve MSF performance in terms of distillate production, longevity, and operational conditions. This is accomplished by a comprehensive analysis of the rate of scale formation, distillate production, and the MSF performance ratio by means of mathematical modelling conducted in Simulink software. To calibrate the effectiveness of HBD as precursor to the MSF desalination process, two MSF models were created: the once-through (OT) and brine recycle (BR) configurations. The MSF models were validated in terms of stagewise distillate production, brine temperature, and coolant temperatures with data from the literature, while neglecting the non-equilibrium allowance. The operational performance of the proposed integration approach was evaluated in terms of the deposition rates of CaCO3, scale thickness, fouling resistance, overall heat transfer coefficient, performance ratio, and production ratio. The examination was conducted from the perspective of water salinity and stream temperature for the integrated HBD-MSF systems. The results show that due to the quality of output water in terms of salinity and temperature, the integration of HBD and MSF improved the performance of MSF by substantially reducing scale formation rates as well as increasing the production of distillate where the scale formation rates were 40.6% and 36.3% lower for the hybrid HBD-MSF-OT and HBD-MSF-BR systems, respectively.