Study On VAE Emulsion Wastewater Treatment

Vinyl Acetate-Ethylene Copolymer Emulsion(VAE) is an important chemical product, There will be a large number of VAE emulsion wastewater during the production processes. The VAE emulsion wastewater is difficult to be treated, with the characteristics of high COD, high turbidity, poor biodegradability and high stability.Serious water pollution will be caused if the VAE emulsion wastewaters are discharged directly into water body.Coagulation-sedimentation and coagulation-air flotation processes are used to treat the VAE emulsion wastewater and effects of the process are studied in the study.The efficiencies and influence factors of the VAE emulsion wastewater treatment processes are investigated by composited dosing with inorganic coagulants and organic high molecular flocculants.Experiment results indicate that coagulation-sedimentation and coagulation-air flotation processes are both effective, with the coagulation-air flotation more effective . Under the best experimental condition, the effluent quality of the coagulation-air flotation process can be satisfied with the Class-Two Discharge Standard,specified in the integrated Wastewater Discharge Standard (GB8978-96). In addition, the process is provided with stronger ability of shock resistance load. The optimum conditions of ferric choride dosage, pH value, hydrodynamic condition and other factors are confirmed by experiments.The results can be acted as technical references for engineering applications.The experiment results with composited applications of inorganic coagulant and organic high molecular flocculant indicate that cationic polyacrylamide (PAM) is provided with better coagulation aid action to ferric chloride. The ferric chloride dosage is decreased by a litter addition of cationic PAM for the coagulation-air flotation process. The effluent quality can be satisfied with the Class-Two Discharge Standard, specified in the integrated Wastewater Discharge Standard (GB8978-96).Technical and economical analyses are considered that the VAE emulsion wastewater is treated feasibly by the cogagulation-air flotation process with inorganic coagulant and organic high molecular flocculant. The process has the characteristics of low coagulant dosage, low treatment cost, strong ability of shock resistance load, high and stable treatment efficiency, and better economic benefits.