The Numerical Simulation and Performance Analysis of Seawater Desalination Unit: The Case of SWRO Station with Energy Recovery Devices (ERDs)

Abstract

The demand for good quality drinking water is experiencing strong growth on a global scale, particularly in emerging countries, such as the BASIC countries (Brazil, South Africa, India, and China). For this reason, sea water or brackish water desalination technology using membrane filtration technique is a very effective and sustainable method for dealing with this problem. In this work, the performance study of the reverse osmosis desalination plant of Nouadhibou, Mauritania, coupled or not with an energy recovery unit, was carried out using the Matlab/Simulink software. The objective of this work is to study the functional and productive performance of the reverse osmosis unit by examining the importance of the pressure exchanger in such systems and the impact on the mixing rate of feed water with the flow of water delivered by the pressure exchanger. This study shows that the exploited Energy Recovery Devices (ERDs) provide highly favorable economic and energetic profitability, with a 75% reduction in energy consumption. Specifically, the specific power consumption is reduced from 14.5 kWh/m³ to 5 kWh/m³ when ERDs are used, for a productivity of 800 m³/d and a recovery rate of 20%.