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With the rapid economic development, and chemical products in people's production and life embodied a more important role, however, with the increasing number of chemical products, the production process of environmental pollution is gradually increased, the harm to human health is also increasingly common and severe. Especially fine chemical products (such as pharmaceuticals, dyes, cosmetic, etc.) discharged during the production of organic matter, a large part of the complex structure, difficult to degrade toxic and biological substances. Therefore, chemical wastewater treatment difficult. So study chemical wastewater removal of organic pollutants environmental pollution has become an important task at work. Removal of organic matter in the wastewater in many ways, and flocculation process with easy to operate, cost-effective features, can simplify many complex treatment process. By adding flocculant to the wastewater, the wastewater utilization of natural precipitation is difficult to precipitate out of the fine suspended solids and colloidal particle removal. In this experiment, three kinds of commonly used inorganic coagulant and an organic polymer flocculant, study their effects on chemical wastewater depth treatment effect. They are aluminum sulfate (Al 2 (SO 4 ) 3 ), ferric chloride (FeCl 3 ) , polyaluminum chloride (PAC), polyacrylamide (PAM). Through the experiment, identified four flocculant dosage, the optimum pH and optimum hydraulic conditions. As well as inorganic and organic flocculants complex pilot study, obtained results are as follows: (1) When the flocculant alone, the removal of pollutants from high to low is PAC> FeCl 3 > Al 2 (SO 4 ) 3 > PAM. PAC best effect, the optimal dosage of 40mg / L, turbidity, COD, aniline, nitrobenzene removal rate were 89.9%, 36%, 30.7%, 27%. Optimum pH values ??were Al 2 (SO 4 ) 3 pH = 7; FeCl 3 pH = 5 ; PAC pH = 8. Visible, FeCl 3 in acidic conditions flocculation best, Al 2 (SO 4 ) 3 in neutral conditions to achieve the best treatment effect, PAC in alkaline conditions to achieve the best treatment effect. (2) When the inorganic and organic flocculants, the removal of pollutants from high to low is PAC PAM> FeCl 3 PAM> Al 2 (SO 4 ) 3 PAM. Which PAC PAM best effect, the dosage is 40 2mg / L, the turbidity, COD, aniline, nitrobenzene removal rates were 94.1%, 57.5%, 42.2%, 38.9%. (3) Slow mixing time 15 minutes for each flocculant chemical treatment of wastewater optimal mixing time.
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