Treatment Of Acrylic Fiber Wastewater With Oxidized PSF

Acrylic fibers wastewater with sophisticated ingredients is a typical organic effluent which is very hard to be disposed.A various of refractory organics,which still exist in the acrylic fibers wastewater after biological treatment,have pernicious influences to living beings.Some advanced water treatment technologies that are applied in acrylic fibers wastewater,which are the urgent demand with the improvement of the emission standard.Coagulation has been dismissed as a advanced processing technology of high performance price ratio because of high coagulation efficiencies,low price, simple operation and convenient management,which have been become the preferred technology in process of acrylic fibers wastewater treatment.However,traditional coagulants show limited abilities for the refractory organic pollutants removal,which result in the fact that residual CODcr cannot meet new emission standards.In this paper,aim at the refractory organic pollutants from acrylic fibers wastewater after biological treatment,an oxidized ploysilicate aluminum iron flocculant of inorganic composite polymer was synthesized to treat this wastewater.The synthesis optimization and operation conditions optimization were studied.In addition,by investigating the structural of coagulant,the coagulation efficiencies and floc structure characterizations,explored the mechanism of coagulant,so that the oxidized ploysilicate aluminum iron coagulants will be applied in the acrylic fibers wastewater after biological treatment system.The main contents and results are following:With ferric sulfate,sodium silicate,sodium chlorate and sulphuric acid as raw materials,the oxidized ploysilicate aluminum iron coagulants was prepared.The results shows that the optimal synthesized conditions of flocculation are:initial p H of the flocculation 1.67,dosage of sodium chlorate 8g/L,molar ratio of ferric to aluminum 1.3, curing time 3d.The synthesized flocculation morphology is characterized by SEM and TEM technology.The result shows that the flocculation isn’t easy admixture between polysilicate and polymerization of iron,but the complicated polymerization.The a polymer oxidation polysilacid iron flocculation is irregular and non-crystal morphology.The oxidized ploysilicate aluminum iron flocculant was adopted to study systematically initial p H,coagulant dosag and slow-stirring time by dealing with biological effluent of acrylic fibers wastewater.The results shows that the optimal operation conditions of flocculation are: initial p H 7,coagulant dosag 1.548mmol/L, slow-stirring time 20 min.On this condition,the removal rate of CODcr、DOC、TN and turbidity reached the maximum,namely 43.00%,36.80%,18.00% and 97.37%,it reached the first-class criteria specified in acrylic fibers wastewater of the comprehensive wastewater discharge standard(GB8978-1996).Scanning the wastewater before and after treatment,we find that visible humus,protein and UV humus of acrylic fiber wastewater after biotreatment can be removed efficiently.The effects of oxidized ploysilicate aluminum iron flocculant are better than the traditional PFS and PASS.The the mechanism by oxidized ploysilicate aluminum iron coagulant was researched.The changes of p H with the curing time,the type and degree of pollutants removal and floc propertie were investigated by p H meter and small-angle laser light scattering technology.The results show that p H value variation is the result of complex ploymerization between polysilicate and polymerization of iron.The flocs of the oxidized ploysilicate aluminum iron display higher growth rate,higher strength and resilience when compared with PS.Due to strong ionic strength in wastewater, the oxidized ploysilicate aluminum iron plays a significant role in charge neutralization.