Industrial Application Of Electrochemical Oxidation Technology For Special Refining Wastewater

Special refining wastewater is the combination of wastewater in oil storing and transportation as well as that in passivation of oily wastewater during the production process of processing enterprises of marine transportation oil.The characteristics of this wastewater are complex water quality,drastic fluctuations,overload contaminants and poor biodegradability so that it can not be treated in integrated wastewater treatment plants,which would influence the production of enterprises.Targeting with the special refining wastewater of a certain processing enterprises of marine transportation oil,the paper analyzes the the features of the water quality and volume,puts forward a clean,economical and efficient electrochemical oxidation technique and applies it into industrialized devices so as to provide reference for the industrialized application of electrochemical oxidation technique in petrochemical wastewater treatment.The industrialized device adopts the process of oil separation--flotation--electrochemical oxidation--neutralization--filtration,showing that if the anode is Ti/Ru O₂-Ir O₂coated plate electrode,while the cathode is titanium plate electrode,and the current densities is 275 A/m²,the average removal amount of COD is 405 mg/L,the average removal amount of ammonia nitrogen is 75.2 mg/L,and biodegradability rises by 0.129.During the process,the influent water quality fluctuates drastically,with ammonia nitrogen peaks at 191 mg/L,while COD peaks at 2206 mg/L.The indicators of effluent can still comply with the requirements of integrated wastewater treatment plants by reducing processing capacity and increasing current density.The total investment of industrialized device is about 743,100 RMB and the cost of operation is about 11.2 RMB/m³.Operating for 186 days stably,the device treated24035 m³of special refining wastewater,reduced 1.81 tons of ammonia nitrogen,9.74tons of COD,0.69 tons of petroleum oil,6.48 tons of suspended solids,and 0.395 tons volatile phenol,easing the burden of integrated wastewater treatment plant,achieving the environmental benefits of enterprises,while saving 30,100 RMB for sewage charges for enterprises.