Effect Of Interaction Of Phosphorus Components With Coagulant On Phosphorus Removal Effect By Chemical

The current situation is that the sewage plant tail water should meet the higher discharge standards,this study targets a certain urban sewage plant in northeast China,it takes the object to explore the spatial and temporal variation of phosphorus components of sewage plant water intake,secondary biochemical treatment and deep treatment effluent under different environmental conditions;The removal effect of single and compound condensants was investigated;using VISUAL MINTEQ to predict total phosphorus（TP）;At the same time,the simultaneous removal of COD,suspended matter（SS）and ammonia nitrogen（NH₄-N）is investigated.In spring,The phosphorus components of water intake stage,biological stage,water outlet stage of the secondary sedimentation pool and water effluent stage is TP>STP>SRP>PP>other dissolved phosphorus>other dissolved inorganic phosphorus>other dissolved organophosphates.In summer,The phosphorus components of water intake stage,water outlet stage of the secondary sedimentation pool is TP>PP>STP>SRP>other dissolved phosphorus>other dissolved organophosphates>other dissolved inorganic phosphorus.In summer,the TP decreased from 5.346 mg/L to 0.274 mg/L,the removal rate is 94.9%;In winter,The phosphorus components of water intake stage,biological stage,water outlet stage of the secondary sedimentation pool is TP>PP>STP>SRP>other dissolved phosphorus>other dissolved organophosphates>other dissolved inorganic phosphorus.In winter,the TP decrease from 1.705 mg/L to 0.221 mg/L,the removal rate is 87.6%.In the sewage treatment plant process,The best processing effect of TP is achieved in the secondary sedimentation pool treatment stage,the removal rate is 62.8%.The best processing effect of total dissolved phosphorus（STP）is achieved in the secondary sedimentation pool treatment stage,the removal rate is 47.4%.The best processing effect of soluble active phosphate（SRP）is achieved in the secondary sedimentation pool treatment stage,the removal rate is 49.9%.The best processing effect of granular phosphorus（PP）is achieved in the secondary sedimentation pool treatment stage,the removal rate is 72.6%.The best processing effect of other dissolved phosphorus is achieved in the biological stage,the removal rate is21.4%.The best processing effect of other dissolved inorganic phosphorus is achieved in the deep treatment stage,the removal rate is 19.1%.The best processing effect of other dissolved organophosphates is achieved in the biological stage,the removal rate is 35.0%.At the same time,the effect of single coagulant on phosphorus removal effect is explored.Through the analysis of TP and other components of water effluent stage,the removal effect of single coagulant on TP is found:Fe Cl₃>Al₂（SO₄）₃>PFS>PAC>Fe SO₄.The removal of PFS is the best for other dissolved phosphorus,and other dissolved organophosphates,and Fe SO₄is the least desirable for each phosphorus component.At the same time,the coagulant has removal effect of SS,COD and NH₄-N,therefore,the removal of contaminants improves the removal efficiency of coagulant.Meanwhile,the prediction of TP can be achieved using VISUAL MINTEQ.Fe Cl₃+Fe SO₄is significantly enhanced on the removal of other dissolved phosphorus,other dissolved organophosphates and other dissolved inorganic phosphorus,The removal effect of the composite coagulant Fe Cl₃+Fe SO₄is better enhanced for TP,STP,SRP,PP;The effect of Fe SO₄+Al₂（SO₄）₃removes TP,STP and SRP is obvious enhanced;It removes them better than placing Fe SO₄or Al₂（SO₄）₃alone,Its removal effect exceeds the removal effect of Fe Cl₃.The removal effect of the composite coagulant Fe SO₄+Al₂（SO₄）₃is better enhanced for PP and other dissolved organophosphates;The removal effect of the composite coagulantPFS+PAC is better enhanced for PP,other dissolved phosphorus,other dissolved inorganic phosphorus and other dissolved organic phosphorus.