Study On The Phosp Horus Adsorption By The Utilization Of Waterworks Sludge

As far as we know, phosphorus plays an important role in the eutrophication process,the modified Waterworks sludge is used to removal phosphorus in the water, which is notonly the utilization of sludge and also provides a new possibility for sewage phosphorusremoval and eutrophic water repair.In this study, waterworks sludge is the research object. To explore the phosphorusadsorption of waterworks sludge and modified sludge, it study on the sludge phosphorusadsorption isotherm and adsorption isotherm fitting, modified sludge adsorption kineticsexperiments, modified condition optimization, phosphorus adsorption of modified sludgein the overlying water, content of phosphorus’ existing forms in modified sludge and theformation of bio-available phosphorus. The results showed that modified sludge had biggerphosphorus adsorption capacity than waterworks sludge. For the high concentration ofphosphorus solution, the40:1(solid-liquid ratio) modified waterworks sludge obtainedbest adsorption effects.As for the concentration not more than20mg/L of phosphorussolution, the80:1modified waterworks sludge obtained best adsorption effects. Thephosphorus adsorption isotherm fitted well as Langmuir and Temkin equations, thecorrelation coefficients were0.904-0.988. In the adsorption kinetics test, Phosphorusadsorption of40:1modified waterworks sludge increased by increasing initial phosphorusconcentration, initial pH and decreasing sludge dose. Constantly added exogenousphosphorus, the DIP and TP of the overlying water continued to rise, but the stirringmodified sludge could adsorb longer. For different forms phosphorus analysis of modifiedwaterworks sludge, it indicated that phosphorus contents of the different forms in static andstirring modified sludge were as follows: Fe/Al-P> Ca-P> NH4Cl-P> Res-P, the content ofFe/Al-P were4350mg/kg and6640mg/kg, it occupied the major proportion, which was ashigh as79.47%,83.71%, the stirring sludge was good for the formation of Fe/Al-P. Thefour bio-available phosphorus content of the modified sludge were as follows:AAP>Olsen-P>WSP>RDP,AAP in the stirring sludge and static sludge accounted for55.15%and62.30%of Fe/Al-P, it showed it could form less non-occluded Fe/Al-P understirring. Non-occluded Fe/Al-P in stirring sludge and static sludge accounted for46.17%and49.16%of total inorganic phosphorus, it showed stirring can promote the formation ofdifficulty releasing phosphorus.