Advanced Treatment of Wastewater on Nonbiodegradable Organic Matters from Alcohol Industry Using Chemical Coagulation and Ozonation Process

Abstract

The chemical coagulation and ozonation process was used as a advanced treatment to treat the effluent of waste water from a alcohol industry. Used chemical oxygen demand(COD) as the parameter for decision-making. Previously, chemical coagulation experiments were conducted for the optimal coagulation dosages determination, for the coagulants ferric chloride(FC),PAC,PFS, aluminum sulfate(AS) and ferrous sulfate , the experiment results indicated that FC had the highest COD removal efficiencies ,as its good performance, FC was chose as the coagulant for primary chemical coagulation before ozonation. In ozonation experiments, ozone dosages and pH were studied for their influences on COD removal efficiencies 1 , it was found that COD removal rate increased while the pH in the solution rose simultaneously, and when increased ozone dosages, the same behavior was observed. When the dosage of the coagulant, ozone and pH reaches 200 mg -1 , 1224 mg -1 and 12, respectively, the COD value was 98 mg -1 , with the total COD removal efficiency reaches 80%. Using gas chromatography/mass spectrometry (GC/MS) technique to measure the carbon number of the organic matters during the process, the results implied that ozonation had the advance in decreasing carbon numbers of organic matters in the source water and transforming nonbiodegradable organic matters into acid, phenol and ketone compounds which are easy to be decomposed by microorganisms.