Parallel and series multistage air gap membrane distillation

• Published in: Desalination Vol. 417; pp. 69 - 76
• Main Authors: Khalifa, Atia E., Alawad, Suhaib M., Antar, Mohamed A.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2017
• Subjects: And energy analysis; Comprehensive experimental investigations; Membrane distillation; Multistage air gap system; Operating conditions; Multistage air gap system; And energy analysis; Comprehensive experimental investigations; Membrane distillation; Operating conditions
• ISSN: 0011-9164; 1873-4464
• DOI: 10.1016/j.desal.2017.05.003

The performance of multistage air gap membrane distillation (MS-AGMD) system is experimentally investigated. The effects of feed temperature and flow rate, coolant temperature and flow rate, air gap width, and feed concentration on the system performance are studied. Parallel and series flow stage connections for the feed stream and coolant stream are tested. Energy analysis is performed for the MS-AGMD and compared with the single stage system. Parallel stage connection shows better performance than series connections in terms of permeate flux and energy consumption. The distillate volume of MS-AGMD module is measured to be 2.6 and 3 times the distillate volume of single stage AGMD module, for series and parallel stage connections; respectively. However, the specific energy consumption of multistage system is only 1.5 times the single stage system. The gain output ratio of the parallel stage MS-AGMD system is higher than the series stage MS-AGMD system, and it reached 0.6 for parallel MS-AGMD system and 0.45 for the series MS-AGMD system, at 90°C. •Water desalination using membrane distillation (MD) technique•Design and construction of Multistage air gap MD system•Parallel and series stage connections•Comprehensive experimental investigations of operating conditions and design parameters•Energy analysis and performance indicators.