Energy consumption and recovery in reverse osmosis

TLDR

Energy consumption drives freshwater production cost in reverse osmosis, and while energy recovery options have been explored, achieving minimum theoretical specific energy consumption is hindered by concentration polarization, fouling, and hydraulic resistance, making combined energy and water recovery a promising alternative for both small and large scale RO. This review aims to evaluate existing process configurations and operating strategies to identify pathways for energy and water recovery that enhance RO performance. The authors analyze current configurations and strategies, discussing potential recovery and recycling approaches to improve RO efficiency.

Abstract

Energy consumption is a key factor which influences the freshwater production cost in reverse osmosis (RO) process. Energy recovery and reuse options have already been very well explored in the current desalination industry. Achieving minimum theoretical specific energy consumption for water recovery is not feasible due to effects of concentration polarization, membrane fouling and hydraulic resistance to permeate flow. Due to these limitations, energy recovery along with water recovery can be a better alternative to improve energy consumption and economics of the RO process both in small and large scale applications. This paper reviews currently available process configurations, operating strategies, and discusses potential pathways to recover and recycle energy and water to improve the performance of the RO process.