Adsorption materials of nitrate and phosphate removal in secondary effluent advanced treatment

To solve the problem of high-concentration nitrogen and phosphorus in secondary effluent, nature zeolite was modified and compounded to remove nitrogen and phosphorus by using adsorption process. Experimental results show that among these four modification methods, the modification effects can be seen as follows:salt and thermal modification 〉 salt modification 〉 thermal modification 〉 acid modification. After salt and thermal modification, the capability of ammoniacal nitrogen removal increases by 31.58%. The optimal conditions of salt and thermal modification are modifying in NaCl solution of 5.7% in mass fraction for 2 h, then 0.5 h calcination at 500℃. After compounding, the capability of phosphorus removal increases obviously. The optimal conditions of compounding are compounding in LaCI₃ solution of 0.4% in mass fraction for 1 h, then 1 h calcination at 200℃. Using the modified adsorption martial to treat effluent from a secondary sedimentation tank, the problem of substandard nitrogen and phosphorus contents of effluent can be solved effectively.