Prepare Polysilicate Ferric Chloride With Coal Fly Ash

In this thesis ,KF was determinde to be the flux for fly ash roasting,and the optimum calcination conditions for fly ash roasting were determined by the orthogonal experimental method,which the dissolution rates of the aluminum and iron in the Calcined products was studied.The technologies for acid leaching of fly ash were determined by the orthogonal experimental method and test and single factor orthogonal experimental method to add, which the dissolution rates of the aluminum and iron in the Calcined products were studed.. The preparation of PAFC was defined by comparison to the simulated water with the same turbidity . NaOH solution, Al (OH) 3 sol were respectively put into the mixed solu-tion of Aluminum chloride and ferric chlorideas the pH regulato to prepared the PAFC.In this thesis Ferric Chloride Coagulant Polysilicate was prepared from PAFC flocculant and Polysilicate with the method of Composite Aggregation ,using the coal fly ash as the raw ma-terial,and the process condition was determined : n(Al+Fe):n(Si)=10:1(Amount of substance(mol)),Polymerization temperature 60℃,pH=3~4.The calcination temperature of fly ash was reduced from traditional 850℃to 700℃in the action of KF,determined by the dissolution rate which was investigated by orthogonal experiments. the mass ratio between coal fly ash and KF is 5:1. Leaching acid concentration was reduced , which was used to submerge fly ash.Acid leaching conditions in this paper was determined :m(coal fly ash):m(15﹪HCl)=4:1, Stirred at 75℃for 2h. Ferric chloride mixed solution can be obtained after acid leaching.CoMParisons between Al(OH)3 and NaOH as a polymerization regulator respectively showed that the Al(OH)3 was better than the aggregate NaOH in preparation ,because there was no delamination when Al(OH)3 was put into as NaOH.. preparatory technological condition was determined :pH 3-4,(Al):n(Fe)=9:1,reaction temperature 60℃,reaction time2 h..Determine the conditions of alkali fusion reaction was determined: 150℃,0.4 MPa,m(coal fly ash residue):m(20﹪NaOH)=4:1.Preparation of polysilicate determined process conditions was determined by changing pH3-4 , concentration of SiO24﹪. This paper use PSAFC to dispose Gaolingtu simulated water,Determine the best input delivery of PSAFC:Temperature 20℃,Stirring speed 100 r/min,pH 6-9,Still more than 20 minutes .In the same case dosage, PSAFC relatively has a better removal rate of tur-bidity , in the condition of coMPared with other commercial flocculants. Disposed lake water and Printing and dyeing wastewater with PSAFC.Removed the turbidity higher than 95﹪,and ,COD higher than 85﹪in the dosing quantity for 2 mg /L.