Evaluation of advanced phosphorus removal from slaughterhouse wastewater using industrial waste-based adsorbents
Shengdan Sun1, Chuanping Feng2, Shuang Tong3
1School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing, 100083, China; Beijing Key Laboratory of Meat Processing Technology, China Meat Research Center, Beijing 100068, China
Abstract:
Slaughterhouse wastewater (SWW) contains high concentrations of phosphorus (P) and is considered as a principal industrial contaminant that causes eutrophication. This study developed two kinds of economical P removal adsorbents using flue gas desulfurization gypsum (FGDG) as the main raw material and bentonite, clay, steel slag and fly ash as the additives. The maximum adsorption capacity of the adsorbent composed of 60% FGDG, 20% steel slag, and 20% fly ash (DSGA2) was found to be 15.85 mg P/g, which was 19 times that of the adsorbent synthesized using 60% FGDG, 30% bentonite, and 10% clay (DSGA1) (0.82 mg P/g). Surface adsorption, internal diffusion, and ionic dissolution co-existed in the P removal process. The adsorption capacity of DSGA2 (2.50 mg P/g) was also evaluated in column experiments. The removal efficiency was determined to be higher than 92% in the first 5 days, while the corresponding effluent concentration was lower than the Chinese upcoming SWW discharge limit of 2 mg P/L. Compared with DSGA1, DSGA2 (synthesized from various industrial wastes) showed obvious advantages in improving adsorption capacity of P. The results showed that DSGA2 is a promising adsorbent for the advanced removal of P from SWW in practical applications.
