Liquid - Liquid Extraction Method To The High Chlorine Refractory Organic Wastewater

Some high chlorine-ion refractory organic wastewater is negative parts in Phenylhydrazine and Ethylchloride producing. The pH Value of the wastewater is 0.93, the CODc1 is 39406 mg/I, BOD5ICODr is 0.02, and the Chlorine ion is high to 56563 mg/I. The flow of the water is 100 m3/d. At present there are no valid treatments for this kind of water. In this paper, the removal of chlorine ion of the wastewater by liquid-liquid extraction, the concentration of the chlorine ion in 5% NaOH solution and the bio-degradation of the organic wastewater were studied, The proper theoretical analyses were carried out correspondingly. The extraction factors including the initial p1-I Value, the initial Chlorine ion concentration, liquid to liquid ratio and organic phase ratio of the imitated wastewater were studied. The optimal conditions were determined. The lower of the pH Value and Chlorine ion concentration were, the easier to remove the Chlorine ion from wastewater. The ratio of diluent and extractant was 4:3. The liquid to liquid ratio was 0.35. Under the selected conditions the experiment results of the wastewater showed that the Chlorine ion extracting rate came to 83.2%, the removal rate of CODEr was about 89.2%. The B/C was increased from 0.02 to 0.34. At the same time the recycle of the extractant was studied. The treatment to loaded extractant by 5% NaOH solution before distill was determined. The Chlorine ion concentration in the 5% NaOH solution was about 139 g/l. The used extractant can be reused after regeneration by adding 5% NaOH water solution. The ratio of loaded extactant and 5% NaOH solution was 5:4. After extraction treatment, wastewater was treated by PAM and PFS flocculants. The optimal pH Value range was from 7. 12 to 7.70, the optimal volume of flocculants were 2.5% PFS and 3.0% PAM0 The wastewater was biotreated by two kinds of active sludge. The results shown that the treatment by pesticide plant active sludge was more valid than that of the wine plant active sludge. The wastewater treatment was done after 8 days biotreatment. At last the proper mechanism analyses of extraction and activesludge treatment were carried out.