Wastewater Pretreatment by Normal Freezing Cool Thermal Storage Process with Convective Heat Transfer Mechanism

Chao-Ching Chang; Chih-Ming Chang; Sung-Te Jung; Cheng-Liang  Chang

doi:10.6180/jase.2011.14.2.04

Wastewater Pretreatment by Normal Freezing Cool Thermal Storage Process with Convective Heat Transfer Mechanism

Computer Science and Information Engineering

Chao-Ching Chang¹ , Chih-Ming Chang¹ , Sung-Te Jung² and Cheng-Liang Chang This email address is being protected from spambots. You need JavaScript enabled to view it.¹

¹Energy and Opto-Electronic Materials Research Center, Department of Chemical and Materials Engineering, Tamkang University, Tamsui, Taiwan 251, R.O.C.
²Department of Communication Engineering, Oriental Institute of Technology, Taiwan, R.O.C.

Received: December 1, 2010
Accepted: May 1, 2011
Publication Date: June 1, 2011

Download Citation: ||https://doi.org/10.6180/jase.2011.14.2.04

ABSTRACT

The effect of convective heat transfer mechanism on the wastewater pretreatment by the normal freezing cool thermal storage process was investigated. A mathematical model considering the heat and mass transfers in a normal freezing cool-thermal storage system using wastewater as the phase change material was developed and solved for the approximate solutions. A convective transport of heat in the water phase and constant heat sinking surface temperature of solid phase were considered and incorporated with the system equations to determine the temperature profiles of solid and liquid layers. The effects of system parameters on the solidification rate and the amount of solute removal were studied. The solidification rate would increase with increasing heat transfer coefficient in overall, but an inversed trend occurred initially. The optimal amount of thermal storage and the optimal solidification thickness had been determined. Differences around 10% in the optimum operating time and the cool-thermal storage would be made if different heat transfer mechanisms were assumed in the present aqueous system studied.

Keywords: : Cool-Thermal Storage, Wastewater Pretreatment, Convection, Modeling, Optimization

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