| Title: | Multistage Surface-Heated Vacuum Membrane Distillation Process Enables High Water Recovery and Excellent Heat Utilization: A Modeling Study |
| Author(s): | Liu Y; Wang J; Hoek EMV; Municchi F; Tilton N; Cath TY; Turchi CS; Heeley MB; Jassby D; |
| Address: | "Department of Civil and Environmental Engineering, University of California Los Angeles, Los Angeles, California90095, United States. California NanoSystems Institute, University of California Los Angeles, Los Angeles, California90095, United States. Institute of the Environment & Sustainability, University of California Los Angeles, Los Angeles, California90095, United States. Energy Technologies Area, Lawrence Berkeley National Laboratory, Berkeley, California94720, United States. Department of Mechanical Engineering, Colorado School of Mines, Golden, Colorado80401, United States. Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, Colorado80401, United States. Thermal Energy Science & Technologies Research Group, National Renewable Energy Laboratory, Golden, Colorado80401, United States. Department of Economics and Business, Colorado School of Mines, Golden, Colorado80401, United States" |
| ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
| Abstract: | "Surface-heated membrane distillation (MD) enhances the energy efficiency of desalination by mitigating temperature polarization (TP). However, systematic investigations of larger scale, multistage, surface-heated MD system with high water recovery and heat recycling are limited. Here, we explore the design and performance of a multistage surface-heated vacuum MD (SHVMD) with heat recovery through a comprehensive finite difference model. In this process, the latent heat of condensation is recovered through an internal heat exchanger (HX) using the retentate from one stage as the condensing fluid for the next stage and an external HX using the feed as the condensing fluid. Model results show that surface heating enhances the performance compared to conventional vacuum MD (VMD). Specifically, in a six-stage SHVMD process, 54.44% water recovery and a gained output ratio (GOR) of 3.28 are achieved with a surface heat density of 2000 W m(-2), whereas a similar six-stage VMD process only reaches 18.19% water recovery and a GOR of 2.15. Mass and energy balances suggest that by mitigating TP, surface heating increases the latent heat trapped in vapor. The internal and external HXs capture and reuse the additional heat, which enhances the GOR values. We show for SHVMD that the hybrid internal/external heat recovery design can have GOR value 1.44 times higher than that of systems with only internal or external heat recovery. Furthermore, by only increasing six stages to eight stages, a GOR value as high as 4.35 is achieved. The results further show that surface heating can reduce the energy consumption of MD for brine concentration. The multistage SHVMD technology exhibits a promising potential for the management of brine from industrial plants" |
| Keywords: | "*Water Hot Temperature Vacuum Distillation/methods Membranes, Artificial *Water Purification/methods brine gained output ratio membrane distillation multistage surface heating water recovery;" |
| Notes: | "MedlineLiu, Yiming Wang, Jingbo Hoek, Eric M V Municchi, Federico Tilton, Nils Cath, Tzahi Y Turchi, Craig S Heeley, Michael B Jassby, David eng Research Support, Non-U.S. Gov't 2022/12/30 Environ Sci Technol. 2023 Jan 10; 57(1):643-654. doi: 10.1021/acs.est.2c07094. Epub 2022 Dec 29" |
