Study On The Preparation And Application Of Dimethyldiallylammonium Chloride, Acrylamide Polymer Flocculants

The advantages of the composite flocculant inorganic-organic are low consumption,low cost,wide range of application,high color removal rate and high COD removal rate,which combines the advantages of the inorganic and organic coagulants.Hence,it has a good application prospect.Dimethyldiallylammonium chloride (DMDAAC),acrylamide polymer flocculants were synthesized by polycondensation of propylene chloride,dimethylamine,acrylamide and caustic soda solution with initiators.The structure of the polymer and its aggregation in aqueous solution were examined by means of various instrumental analysis techniques, including IR and Transmission Electron Microscope (TEM).The amount of initiator and the purity of DMDAAC influenced the production of DMDAAC polymer flocculants most importantly.The flocculation efficiency of the polymer for simulative wastewater,printing and dyeing wastewater as well as the flocculation efficiency of DMDAAC polymer flocculants used with PAC was also studied.The experimental results showed that the cationicity,molecular weights of the polymer and molar ratio of DMDAAC polymer had an optimum value under certain polymerization conditions.The structure, the cationicity and the molecular weight had deferent influences on the flocculation efficiency of deferent wastewater.However,the cationicity and molecular weight can not be increased at the same time.Thus,the cationicity and molecular weight should be different for the treatment of printing and dyeing wastewater.Using DMDAAC polymer flocculants together with PAC,not only can the better flocculation performance be achieved,it is also cost effective.DMDAAC polymer is a high efficiency and multi-function organic flocculant.Treating dyeing wastewater is a big problem both at home and abroad.In this experiment,the inorganic coagulant: polyaluminum chloride (PAC),organic decolouring flocculant (DMDAAC polymer) were chosen to treat dispersed dyes,reactive dyes simulation wastewater and real dyeing wastewater,respectively,which aims to learn the effect of their decolorization.(color removal rate,COD removal rate) and the craft condition of coagulant,such as the consumption of coagulant and the pH value,to explore the coagulation mechanism of various kinds of coagulants,and to compare the effect of their decolorization and COD removal to confirm the best craft parameters of the coagulant respectively.The study shows that DMDAAC polymer flocculant ,which is little influenced by pH,has a better decolorization effect towards wastewater of reactive dyes simulation,dispersed dyes simulation and real dyeing wastewater under suitable condition.The color of the dispersed dyes simulation waste water,reactive dyes simulation wastewater,and real dyeing wastewater can be removed greatly as well as the COD.Inorganic coagulant PAC,which is greatly influenced by pH,has great effect on decoloring the dispersed dyes and has less effect on decoloring the reactive dyes and real dyeing wastewater.Established industrialized production process and equipment based on the experimental research, and produced DMDAAC polymer flocculants successfully.