New designs of turbulence promoters to use in saltwater purification processes

Abstract

This paper describes a two-dimensional computational fluid dynamics (CFD) model of flow with mass transfer to simulate a membrane separation system. The fluid domain comprises two reverse osmosis (RO) membranes and is fitted with different wavy inserts that act as turbulence promoters. Four types of insert designs were evaluated in terms of salt deposition on the membranes, permeate flux, axial pressure drop in the channel, and plots of the Sherwood number against the Power number. According to numerical simulations, under the operating conditions of this investigation, the proposed designs generate better results than commercial designs. The gain in pure water flux achieves up to 2%, and salt deposition on the membrane surface is reduced by ~5% than the commercial Zigzag spacer arrangement.

Keywords

• reverse osmosis
• cfd
• desalination
• concentration polarization