Computing the effective diffusion coefficient of solutes in a multi-salts solutions during forward osmosis (FO) membrane filtration: Experiments and mathematical modelling

JOURNAL OF ENVIRONMENTAL MANAGEMENT

卷:214

Article

Liyanaarachchi, S.¹  Muthukumaran, S.^2,3  Kaiser, Joshua⁴  Rogers, Paul⁴  Shu, Li⁵  Shon, Ho Kyong⁶  Jegatheesan, V.¹ 

[1] RMIT Univ, Sch Engn, Melbourne, Vic 3000, Australia

[2] Victoria Univ, Coll Engn & Sci, POB 14428, Melbourne, Vic 8001, Australia

[3] Victoria Univ, Inst Sustainabil & Innovat, POB 14428, Melbourne, Vic 8001, Australia

[4] Deakin Univ, Sch Engn, Waurn Ponds, Vic 3216, Australia

[5] LJS Environm, Parkville, Vic 3052, Australia

[6] Univ Technol Sydney, Sch Civil & Environm Engn, POB 129, Broadway, NSW 2007, Australia

关键词: Effective diffusion;    Forward osmosis;    Concentration polarisation;    Reverse osmosis;    Seawater;   

DOI  :  10.1016/j.jenvman.2018.03.002

来源: Elsevier

【 摘 要 】

Diffusion coefficient of solutes through a porous membrane media is different from diffusion coefficient through a free homogenous media. Porosity, tortuosity and the thickness of the membrane significantly affect the diffusion through a specific thickness of a membrane and therefore it is termed as effective diffusion coefficient (D-eff) which is lower than the actual diffusion coefficient, D. The D-eff of single or dual solutes through a porous membrane layer are well documented but not for multiple salts. Therefore, in this study, single, dual and multiple salt mixtures were passed through a flat sheet cellulose triacetate Forward Osmosis (FO) membrane to obtain a semi-empirical relationship with the D-eff and its water flux. This will allow computing the structural coefficient of FO membranes. Research community have spent tremendous efforts in membrane modification to reduce the structural coefficient to improve FO process efficiency. Our finding suggests that optimising the draw solution chemistry can achieve this goal. (C) 2018 Elsevier Ltd. All rights reserved.

【 授权许可】

Free