The Performance Of Phosphorus Removal From Diluted Phosphorus-containing Wastewater Using MAL Hybrid Adsorbent

With the rapid development of China's industrialization and urbanization, a large quantity of waste water containing nutrients such as nitrogen, phosphorus is discharged into surface water in cities, which leads to eutrophication and algal bloom. With the policy that Water Pollution Control Action Plan introduced in 2015, more and more attention has been paid to the management and prevention of eutrophication. Effluent of municipal sewage treatment plants is an important source of phosphorus of surface water in cities, which can prevent surface water from eutrophication by front-end control if its total phosphorus was advanced removed. MAL composite adsorbent is an inorganic material made of three kinds of metal ions(Mg, Al, La), it has a simple preparation process and a superior defluorization performance, this study mainly focuses on effluent treated by secondary treatment of municipal sewage treatment plants, to evaluate the performance of advanced phosphorus removal at low concentration by MAL composite adsorbent.In batch sorption studies, effects of initial phosphorus concentration, initial solution p H of using MAL adsorbent for advanced phosphorus were studied, and the final p H after treatment was analysed. The results show that the adsorbent has a satisfying effect on advanced phosphorus removal in a large scale of initial solution concentration and p H, and the p H stays stable after treatment. By kinetics analysis, the sorption process of phosphorus was turned out to follow pseudo-second-order kinetics and intra-particle diffusion model, which indicates that the adsorption process is a chemisorption and mainly controlled by internal diffusion.In fixed-bed colume studies, effects of adsorbent particle size, operating flow rate, environment temperature on breakthrough curve were studied to get the best operating parameters and the most fitting model. At last, actual wastewater treatment at low phosphorus concentrion were both studied by batch and colume experiment based on the previous studies. The colume experiment shows that the MAL adsorbent has a good effect on advanced phosphorus removal of effluent treated by secondary treatment of municipal sewage treatment plants, which provides a preliminary basis for actual operation of adsorbent.Finally, the technical and economic analysis of MAL composite adsorbent was studied, and the production cost in preparation of MAL composite adsorbent was about 6.77 RMB/kg, which means it has a high technical and economic performance.