Effect of membrane performance including fouling on cost optimization in brackish water desalination process

• Published in: Chemical engineering research & design Vol. 117; pp. 401 - 413
• Main Authors: Ang, W.L., Nordin, D., Mohammad, A.W., Benamor, A., Hilal, N.
• Format: Journal Article
• Language: English
• Published: Rugby Elsevier B.V 01.01.2017; Elsevier Science Ltd
• Subjects: Brackish water desalination; Cost model; Costs; Desalination; Economic conditions; Economic evaluation; Energy consumption; Feasibility studies; Fouling; Low pressure; Membrane fouling; Membrane process; Membranes; Nanofiltration; Optimization algorithms; Recovery; Reverse osmosis; Studies; Water treatment; Water treatment plants; Cost model; Membrane fouling; Membrane process; Brackish water desalination; Economic evaluation
• ISSN: 0263-8762; 1744-3563
• DOI: 10.1016/j.cherd.2016.10.041

•Membrane selection for optimum brackish water desalination operation was presented.•Verberne Cost Model was employed to evaluate the total cost of the membrane unit.•Economic and fouling assessments were used to select the most suitable membrane.•High permeability membrane did not guarantee energy consumption and cost savings.•Impacts of different membranes and recovery rates on water costs were investigated. Membrane selection is a crucial step that will affect the economic feasibility of the membrane water treatment process. A comprehensive evaluation consisting of Verberne Cost Model, assessment of membrane performance and fouling propensity, osmotic pressure differential (OPD) and specific energy consumption (SEC) was employed to determine the potential of nanofiltration (NF 270, NF 90 and TS 80) and low pressure reverse osmosis (XLE) membranes to be used in brackish water desalination process. The aim was to save costs by replacing the typical brackish water reverse osmosis (BW 30) membrane. Verberne Cost Model showed that higher flux NF membranes resulted in lower overall costs. However, after assessing the membrane performance, NF 270 and TS 80 were excluded due to their high fouling propensity and their failure to reduce total dissolved solids (TDS) in the solution. Instead, NF 90 membrane which produced water with acceptable TDS and has moderate permeability ended up to be more cost competitive compared to BW 30 membrane, with 17–21% lower total costs and 13–17% lower water costs. Apart from this, OPD and SEC were applied to justify the selection of optimal membrane recovery rate based on the water costs calculated. It was determined that the optimal recovery rate was 80% where the SEC and water costs were close to available water treatment plants. Overall, this study showed that the selection of membrane can be carried out by using Verberne Cost Model assisted by assessment of membrane performance and fouling propensity, OPD and SEC.