Research On Depth Treatment By Different Catalysts In Fenton-like Method For Pharmaceutical Wastewater And Pulp And Paper Wastewater

This topic had advanced treated for two typical refractory wastewater using different catalysts in Fenton-like method.The two types of wastewater were Pharmaceutical wastewater from secondary settling tank of Zhongyuan Pharmaceutical Factory and Pulp and paper wastewater from Secondary settling tank of Luohe Silver Pigeon Industrial. In this paper,both of the twowastewater characteristicsand hazards had beendescribed,anddomestic and foreign researchhad been reviewed.First,the experiment had carried modified fly ash which is one of the catalysts of this experiment, respectively, to the pharmaceutical wastewater and pule and paper water.With COD removal as the main index the experiment research was carried as following:(1)The results show that different kinds of coalfly ash have different structure,chemical composition and ingredients which will affect catalytic and adsorption properties.With the pharmaceutical wastewater and papermaking wastewater as the research objects,the adsorption and catalytic properties of BFAare higher than TFA;(2)BFA fly ash had been modified in different waysandthe sequences of catalytic effect of pharmaceutical wastewater showed that acid modified> unmodified> hot modified>alkali modified.The sequences of catalytic effect on the pulp and paper wastewater is acid modified> hot modified> unmodified>akali modified.It was found that acid treatment on fly ash could effectively improve the catalytic effect.Then,the experiment had advanced treated for two wastewater using two different Fenton-like methods.(1)Experimental study of modified fly ash in Fenton-like method for pharmaceutical wastewater, which use orthogonal test and single factor experiments to study reached the following optimal conditions:without adjusting the pH of raw water, the dosage of modified fly ash,H2O2and FeSO4·7H2O was28g/L,6.6mmol/L,11.2mmol/L,respectively,the reaction time was60min. Under the optimal conditions,COD removal effiency reached65.54%;(2)Experimental study of micro-electrolysis combined with H2O2technics of Fenton-like method for pharmaceutical wastewater,which use single factor experiments to study reached the following optimal conditions:under the optimal conditions thatFe:C was1:1,pH value was2.5,reaction time was60min,the dosage of H2O2was12.24mmol/L, which COD removal effiency reached71.56%;(3)Experimental study of modified fly ash in Fenton-like method forpulp and paper wastewater, which use orthogonal test and single factor experiments to study reached the following optimal conditions:without adjusting the pH of raw water,the dosage of modified fly ash, H2O2and FeSO4·7H2O was34g/L,8.2mmol/L,8.8mmol/L,respectively,the reactiontime was45min. Under the optimal conditions, COD removal effiency reached71.72%.(4)Experimental study of micro-electrolysis combined with H2O2technics of Fenton-like method for pulp and paper wastewater, which use single factor experiments to study reached the following optimal conditions:under the optimal conditions thatFe:C was1:1,pH value was3, reaction time was75min, the dosage of H2O2was14.69mmol/L, which COD removal effiency reached75.84%.While,carried out the following comparative experiments for the two different wastewater:(1)Comparative test of catalytic oxidation and adsorption properties for the modified fly ash was carried.It is obtained that pollutants eventually removed mustrely on the catalytic oxidation ability of modified fly ash.(2)The release of the Fe2O3,CuO and TiO2reduced with the reaction times increasing, for the more,the fly ash powder is not easily separated from floculent precipitate,which affect the repeated use of fly ash.(3)Comparative test of micro-electrolysis and micro-electrolysis with H2O2of Fenton-like method was carried. It is obvious thatCOD removal of the two different types wastewater had significantly improved with the addition of H2O2.What’s more,it proved that H2O2much more significantly strengthened the test results.This article provides a theoretical basis in practical engineering application of Fenton-like method,while widening the various choices of catalyst in the Fenton-like method.This study had important practical guiding significance on the treatment of refractory wastewater.