Enhanced Performance of Membrane Distillation Using Surface Heating Process

Membranes

Xiaoyuan Zhang¹  Kang Wang²  Fei Han²  Shuxun Liu² 

[1] Advanced Environmental Biotechnology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, Singapore 639798, Singapore;School of Civil and Transportation Engineering, Hebei University of Technology, Tianjin 300401, China;

关键词: membrane distillation;    surface heating;    hypersaline water treatment;    temperature polarization;    thermal efficiency;    specific energy consumption;   

DOI  :  10.3390/membranes11110866

来源: DOAJ

【 摘 要 】

Membrane distillation (MD) is a thermally driven desalination process that has excellent application prospects in seawater desalination or hypersaline wastewater treatment, while severe temperature polarization (TP) and the resulting relatively high energy consumption have become principal challenges limiting the commercial application of MD. Therefore, the design of novel systems to overcome the shortage of conventional MD requires urgent attention. Here, we developed three surface heating vacuum membrane distillation systems, namely, SHVMD-1, SHVMD-2, and SHVMD-3, according to the different positions of the thermal conducting layer in the cell. The distillate flux, TP, and energy performance of these systems under different operating conditions were investigated. All three systems showed stable performance, with a salt rejection >99.98% for 35 g/L NaCl, and the highest flux was close to 9 L/m²·h. The temperature polarization coefficients were higher than unity in SHVMD-2 and SHVMD-3 systems, and the SHVMD-2 system produced the lowest specific energy consumption and the highest thermal efficiency. In addition, we tested the intermittent surface heating process, which can further improve energy performance through reducing specific electrical energy consumption in vacuum membrane distillation. This paper provides a simple and efficient membrane system for the desalination of brines.

【 授权许可】

Unknown