Treatment of the wastewater with high concentration of salt and organic matters using the combined methods with freezing
YANG Hui1,,, WANG Rui1, FU Mengxiao1, JIANG Yuanfei1, SHI Yanzhuo1, GUO Baoxia1, LI Caibin2 1.Beijing Municipality Key Lab of Heating, Gas Supply, Ventilating and Air Conditioning Engineering, School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing 100044, China 2.Beijing Sustainable Green ET. Co. Ltd., Beijing 100192, China
Abstract:During the solution freezing process, impurities are expelled by ice formation from water molecules. In this study, gravity-induced, microwave or centrifugal treatment methods were combined with freezing method to remove the salt and organic matter from wastewater. For the simulated wastewater with the initial chemical oxygen demand (COD) of 10 000 mg·L?1 and the initial salinity of 10 000 mg·L?1, treatment experiments were carried out using three combined methods: freezing, gravity-induced and centrifugal method (FGCM), the freezing, microwaving and centrifugal method (FMCM) and the freezing, microwaving, gravity-induced and centrifugal method (FMGCM), to investigate the organic matter and salt removal rates. The results show that FGCM had the highest removal rate, but the longest process duration; FMCM had the shortest process duration, but the lowest removal rate; FMGCM had similar removal rate as FGCM and could effectively reduce the process duration. These three methods always presented higher organic matter removal rate than salt removal rate. Key words:freezing method/ COD removal rate/ salt removal rate/ gravity-induced method/ microwave treatment/ centrifugal treatment.
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1.Beijing Municipality Key Lab of Heating, Gas Supply, Ventilating and Air Conditioning Engineering, School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing 100044, China 2.Beijing Sustainable Green ET. Co. Ltd., Beijing 100192, China Received Date: 2020-04-28 Accepted Date: 2020-08-17 Available Online: 2021-02-22 Keywords:freezing method/ COD removal rate/ salt removal rate/ gravity-induced method/ microwave treatment/ centrifugal treatment Abstract:During the solution freezing process, impurities are expelled by ice formation from water molecules. In this study, gravity-induced, microwave or centrifugal treatment methods were combined with freezing method to remove the salt and organic matter from wastewater. For the simulated wastewater with the initial chemical oxygen demand (COD) of 10 000 mg·L?1 and the initial salinity of 10 000 mg·L?1, treatment experiments were carried out using three combined methods: freezing, gravity-induced and centrifugal method (FGCM), the freezing, microwaving and centrifugal method (FMCM) and the freezing, microwaving, gravity-induced and centrifugal method (FMGCM), to investigate the organic matter and salt removal rates. The results show that FGCM had the highest removal rate, but the longest process duration; FMCM had the shortest process duration, but the lowest removal rate; FMGCM had similar removal rate as FGCM and could effectively reduce the process duration. These three methods always presented higher organic matter removal rate than salt removal rate.