Flux decline induced by scaling of calcium sulfate in membrane distillation: Theoretical analysis on the role of different mechanisms

Liu，Jie1,2; Wang，Yewei2; Li，Zhuo2; Liu，Xin2; Li，Weiyi2

2021-06-15

10.1016/j.memsci.2021.119257

JOURNAL OF MEMBRANE SCIENCE   影响因子和分区

0376-7388

1873-3123

Membrane distillation (MD) has been recognized as a valuable technique for desalination, water treatment, and other applications. However, MD processes are plagued by the scaling of sparingly soluble salts. This study proposes to investigate the roles of different mechanisms (e.g., temperature polarization, hydraulic resistance, and interfacial effects) in accounting for the flux decline induced by the scaling of calcium sulfate (CaSO) in MD. A mathematical model is developed to describe the nonlinearly coupled heat and mass transfer when correlating geometrical characteristics of the scaling layer. The modeling is combined with characterization experiments to assess the dependence of the flux decline on the cake growth. In addition to the characterization of scanning electron microscopy, the morphological evolution of the scaling layer is in-situ analyzed via an approach based on optical coherence tomography (OCT). The cake-dominated regime is identified by comparing the flux decline with the OCT-characterization results, thereby providing more reliable experimental data for the model-based analysis. It is suggested that the continuous growth of the crystals could substantially vary the geometrical characteristics of the scaling layer at the cake-membrane interface and thereby decrease the vapor flux. This study sheds light on the development of MD processes with improved performance.

Flux decline In-situ characterization Membrane distillation Model-based analysis Scaling of calcium sulfate

SCI ; EI

英语

通讯

WOS:000697104000004

20211210107056

Calcium compounds ; Desalination ; Distillation ; Driers (materials) ; Mass transfer ; Optical tomography ; Scanning electron microscopy ; Water treatment

Water Treatment Techniques:445.1 ; Mass Transfer:641.3 ; Optical Devices and Systems:741.3 ; Chemical Operations:802.3 ; Chemical Agents and Basic Industrial Chemicals:803

CHEMISTRY

2-s2.0-85102633838

Scopus

1.School of Environment,Harbin Institute of Technology,China
2.School of Environmental Science and Engineering,Southern University of Science and Technology,China

Liu，Jie,Wang，Yewei,Li，Zhuo,et al. Flux decline induced by scaling of calcium sulfate in membrane distillation: Theoretical analysis on the role of different mechanisms[J]. JOURNAL OF MEMBRANE SCIENCE,2021,628.

Liu，Jie,Wang，Yewei,Li，Zhuo,Liu，Xin,&Li，Weiyi.(2021).Flux decline induced by scaling of calcium sulfate in membrane distillation: Theoretical analysis on the role of different mechanisms.JOURNAL OF MEMBRANE SCIENCE,628.

Liu，Jie,et al."Flux decline induced by scaling of calcium sulfate in membrane distillation: Theoretical analysis on the role of different mechanisms".JOURNAL OF MEMBRANE SCIENCE 628(2021).