Electrolytic-Deepening Oxidation Of Coking Wastewate

Based on a comprehensive summary of the major treatment technology of the coking wastewater home and abroad, this paper chose the electrolytic-deepening oxidation to treat the coking wastewater, the effects of major electrolytic parameters on the treatment of the major pollutant, the major effects of ferrite oxidation on the degradation ratio of the major contaminant, the choice of optimal processes of electrolytic-deepening oxidation to treat the coking wastewater were evaluated respectively.The electrolysis voltage, the electrolysis time, the dosage of auxiliariy (NaCl) and the pH value are the main factors when treated by electrochemistry. The experimental results showed that: voltage of 10V, electrolysis time of 50 min, auxiliary dosage of 7g / l, pH value of about 9 to 10 are the most excellent electrolytic processing parameters. And the largest removal rates of ammonia and phenol were 88.55% and 41.36%.Using the ferrite solution which is produced by electrochemistry to directly process the simulating coking waste water not only omitted the pretreatment process of ferrite solution and the measures aimed at its instability but also avoided the effects of the instability of ferrite. The removing rate of phenol could achieve 74.15% when the pH value was about 9, the oxidation time was 50min and the dosage of ferrate was 41.67mmol/l, in addition the precipitation of ammonium sulphate salt is notably helpful to remove the NH3-N when adjusted the pH value with the sulfuric acid.Ammonium sulphate salt start to precipitant when the dosage of ferrate was 24.18mmol/l, the pH value was about 9. Phenol is an organic pollution which is hard to degrade in the coking wastewater, the experimental results showed that:the degradation process is similar to meet the first dynamic process when it is treated by electrochemistry or ferrate.Using electrochemistry or ferrate to treat the coking wastewater can't reach the discharge standard, in view of the two approaches,in this paper, the combination of the two: electrolytic-deepening oxidation of coking wastewater gained a preferable effect. The experimental results showed that using ferrate to electrolytic-deepening oxidize after electrochemistry and electrolysis after the ferrate oxidation both can get the high removal rate of the main pollutants in the wastewater. But they are ineffective when treat the actual coking wastewater. Taking into account the complicated elements of actual wastewater dropping ferrate solution while electrolysis after treated by ferrate oxidation and then use the electrochemistry as the third progress received a preferable effect: ammonia of the wastewater fell to 0.0263mg / l (up to the discharge standards), the removal rate of phenol and COD reached 99 .68% and 97.75% which were close to the discharge standards. It's obvious that using the electrolysis–ferrate deepening oxidation to treat the coking wastewater, which needn't to combine biochemical methods can wipe off all kinds of pollutants in the wastewater effectively, and it's a simple method without secondary pollution. Therefore, it's an effective method in treating the coking wastewater...