Research On The Treatment Of Coking Wastewater By Three-dimensional Electrode Combined With Ultraviolet Photocatalysis

The coking wastewater is a kind of organic wastewater which is consideredharmful to the environment and difficult to be degraded. As the enhancement ofenvironmental protection request, high efficient and non-pullution method to deal withsuch industrial wastewater has already become present research focuses. In recentyears, three-dimensional electrodes in process of organic wastewater treatment haveattracted more attention due to its simple equipment, easy operation and no secondarypollution. In this paper, we focused on investigating the treatment of simulated phenolwastewater and high strength coking wastewater using a cell with three-dimensionalelectrode coupled with UV-irradiation using TiO₂as photocatalyst.The aqueous phenol with the concentration of300mg/L was treated by the methodsof ultraviolet catalysis, conventional two-dimensional electrode, three-dimensional andTED/UV with60min, respectively. The results indicated that COD removal rate withTED/UV reached45.43%, which was significantly higher than the other threemethods.The simulated phenol wastewater was degraded by the method of TED/UV withstainless steel plate as the anode and graphite rod as the cathode. The improvement ofcurrent efficiency was attributed to preparing granular activated carbon as particleelectrodes. Half of the activated carbon was coated by cellulose acetate membrane andthe other half was uncoated. The optimal conditions for degrading are as follows: thecell voltage is10.0V; the pH of initial solution is5.0; the processing time is120min;the amount of anhydrous Na₂SO₄and P25are2.0g and0.6g, respectively.Indole in coking wastewater, which is a typical nitrogen-containing heterocyclicorganic compound, can be degraded effectively by the method of TED/UV. In thisresearch, cell voltage and processing time had a certain impact on the removal rate ofindole with the concentration of40mg/L. The results showed that indole wascompletely decomposed with the cell voltage8.0V and the processing time90min.The degradations of influent and effluent biochemical from a coking plant byTED/UV method were studied under the optimal conditions. The results indicated thatCOD removal rates of influent and effluent were52.36%and84.00%, respectively.