How flow configuration impacts the performance of direct contact membrane distillation with localized heating—A concise study

• Published in: Journal of water process engineering 2024-12, Vol.68, p.106397, Article 106397
• Main Authors: Awasthi, Rajeev, Kumar, K. Ravi
• Format: Article
• Language: English
• Subjects: Desalination; Flow configuration; Localized heating; Membrane distillation; Temperature polarization
• ISSN: 2214-7144; 2214-7144
• DOI: 10.1016/j.jwpe.2024.106397

This study comprehensively compares the co-current and counter-current direct contact membrane distillation process with localized heating. The mathematical modelling has been performed using effectiveness–number of transfer units (ε-NTU) method. It is observed that co-current flow configuration outperforms the counter-current flow configuration for most of the operating conditions and thermo-physical characteristics of the membrane. It can be inferred from this study that higher feed temperature, lower flow rates, low feed salinity with a membrane of high porosity and less thickness produces higher distillate flux. When the feed inlet temperature is increased from 50 °C to 90 °C the distillate flux in co-current and counter-current flow configurations increased by 363 % and 316 %. Moreover, co-current flow configuration performed better till 80 °C and then counter-current flow configuration outperformed. However, an increase in membrane porosity has increased the distillate flux approximately by 265 % in both the configurations. Furthermore, the study eliminates the dependency on the empirical estimation of membrane properties for prediction of DCMD performance. Additionally, the detailed study highlights the optimal parameters for designing a DCMD system. •The effect of flow configuration on localized heating in DCMD is studied.•Co-current flow performs better upto 80 °C than counter-current flow with heating.•Overall efficiency of co-current flow is found to be better for most cases.