Factors influencing optimum seawater reverse osmosis system designs

Abstract

Potential seawater desalination applications require an evaluation of both single-stage and two-stage reverse osmosis system configurations when selecting the most cost effective process design for a specific application. The preferred reverse osmosis staging should be derived from cost factors, membrane performance parameters, feedwater characteristics and other application site-specific considerations. This paper presents a comparative analysis of single-stage and two-stage seawater reverse osmosis systems, illustrating how the optimum design is influenced by the choice of operating parameters and related cost factors. Computer aided design techniques used by Fluid Systems in evaluating reverse osmosis array options are discussed. Performance characteristics of Fluid Systems' single-stage and high-flux seawater elements are used in the analyses to arrive at the optimum system designs for a range of feedwater salinities. The approach of using pilot plant test results for long-term performance predictions is described.