| Tt is a serious challenge of the water pollution for all over the word. Flocculantion is a process widely used for waste-water treatment in home and abroad. Compared with the traditional flocculants, the natural polymer flocculant has the characters of efficiency, non-toxic, readily biodegradable, no secondary pollution, and widely used.They are new natural polymer flocculants both the cationic flocculant and the gender flocculant modified. They are widely used in parts of food, agriculture, chemical industry and environmental protection.The cationic flocculant which is called SUSM-a and the gender flocculant modified by wood flour were prepared in this article. We optimized the preparation process and applied the two kinds of plants flocculants in waste-water made by myself, coal washing waste-water and chlorine Wastewater treatment. We studied the treatment process and the results and found the best one. And we also did a preliminary exploration on the mechanism of flocculants. At last we accessed to the following conclusions.1. The best preparation process of the cationic flocculant modified by natural flour is that the mass ratio of wood-powder and NaOH is 2:1, the mass ratio of wood-powder and etherifying agent is 1.5:1,the temperature in reaction is 40℃,the reaction time is three hours and a half, we can synthetize SUSA-a.2. In the application for coal washing waste-water treatment, it turn out to be that the removal rates of turbidity, CODCr and suspended solids in the coal washing waste water is 96.8%,69.3% and 97.9%.When the pH value is 6 to 8, the dosage of SUSM-a is 10mg/L, the poly-aluminum dose is 5mg/L, is the best treatment process. It results that the SAUM-a has an effect in dealing with the chlorinated waste water treatment after a complex and repeated adsorption. The removal rate of chlorinated can reach 36.3%.We improved the preparation conditions and did some research found that SAUM-a1 has more pilot and production value.3.The gender flocculant modified by wood-flour is made in copolymerization reaction. When the mass ratio of AM and wood-flour is 2:1,2% of the product amount of carboxy-methyl for the amount of initiator, the reaction time is 1.5h, the reaction temperature is 60℃,the react condition is the best. When the mole ration of amine and formaldehyde is 1.5:1, the reaction time is one hour, the reaction temperature is 50℃,it is the best condition for Mannich reaction.4. Applied the gender flocculant modified by flour to the treatment of waste-water made by myself, when the dosage of PAC and gender flocculant were 5mg/L and 12.5mg/L, the stirring speed was 200r/min, hold 7.5min is best process condition. The turbidity of the final effluent can reach about 5 with wide pH. In dealing with the coal washing waste-water, the best process conditions were that the amount of PAC and gender flocculant were 5mg/L and 15mg/L, the stirring speed was 200r/min, hold 5min.Finally,the COD removal of the final effluent was more than 65%,the ss removal rate can be above 90%.The treatment of chlorinated waste-water's optimum conditions is that the input dosage of PAC and gender flocculent were 5mg/L and lOmg/L, the stirring speed was 250r/min, hold 10min.The results turn out to be better in acidic surroundings, and the final removal rate of chloride ion was more than 30%.
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