Experimental Study On Synergistic Effect Of Various Flocculant

Water purification has always been an extremely important part of urban construction,so the research on water treatment methods has always been the focus of scientific research.Among various flocculation methods,chemical flocculation can be said to be a convenient and economical flocculation method,so it has been widely used.Flocculants,as the most important component of chemical flocculation,have received more and more attention.Different flocculants have different types due to their different sources and molecular structures,and they can be divided into inorganic flocculants and organic flocculants according to their molecular structures and molecular weights under the condition of single composition.through experimental research,it is found that the flocculation effect can be changed by selecting two or more flocculants from some flocculants for a certain physical and chemical operation,which is called synergistic effect.How to make good use of the synergistic effect so as to achieve a flocculation effect of " 1 + 1 > 2" is the focus of the study.After briefly introducing the relevant technologies of water treatment,the main types of flocculation and the achievements made at present,this paper selects kaolin suspension as the experimental stock solution and uses common flocculants to cooperate to prepare a variety of composite flocculants.Under certain experimental conditions,the composite flocculant and the parent flocculant were tested for flocculation of kaolin suspension with basically the same turbidity to verify the difference between the flocculation effect of the composite flocculant produced by the synergistic effect of the flocculant and that of the single parent flocculant.In this paper,modified starchaluminum sulfate composite flocculant,chitosan-ferric chloride composite flocculant,polyacrylamideferric chloride composite flocculant and polyaluminium sulfate-ferric chloride composite flocculant were prepared to represent inorganic-organic composite flocculant and inorganic-inorganic composite flocculant,and the results of flocculation were analyzed.The flocculation experiment was carried out on the actual water body by using the composite flocculant.Through the removal effect of turbidity,COD,ammonia nitrogen and total phosphorus from the experimental samples,the turbidity removal rate of the composite flocculant of polyaluminium sulfate and ferric chloride was 88 %,COD removal rate was 82%,ammonia nitrogen removal rate was 46.3%,and total phosphorus removal rate was 88.7%.It was found that the polymeric aluminum sulfate-ferric chloride composite flocculant had the best flocculation effect for the Tangshan surface water taken this time.Figure22;Table4;Reference186.