| It studied the treatment of coking wastewater by supercritical water oxidation.Coking wastewater is a complex industrial waterwaste, it contains toxic and hazardous substances which is difficult to degrade. The traditional biochemical process have low removal efficiency and high cost. An device was established,which is used for SCWO and CSCWO experiments. Major pollutants in coking wastewater, as COD, ammonia, cyanide, sulfur cyanide were removed by using this equipment, the main product was CO2, H2O, N2. The experiment shows that this experimental device for coking wastewater treatment have a good effect, and no secondary pollution.The reaction temperature in this experiment is 400-500℃, reaction pressure is 24-30MPa, oxidant is excessive H2O2. It can promote the oxidation and decomposition by icreasing the reaction temperature, reaction pressure, residence time, proxynitrite multiples. The removal of pollutants were less affected by proxynitrite times, the orders of the fators from small to large were time, pressure, temperature by orthogonal with the first three factors.In supercritical water oxidation of single factor experiments, cyanide and sulfur cyanide on the temperature and pressure is lower. It is easy for them to have good effect. But COD and ammonia need a higher temperature and pressure.In order to reduce experimental conditions for removing COD and NH3-N, It choose Cu (NO3)2, Mn (NO3)2, Fe (NO3)2 as catalyst in homogeneous reaction. The experiment shows that, adding the catalyst can improve the reaction rate, reduce eaction temperature and pressure. In the same experiment environment, removal efficiency is better for atalytic oxidation reaction. Cu2+ as a catalyst is more appropriate in homogeneous catalysis of supercritical water oxidation reaction.The reactor material for 316L, would be caused corrosion, which could make negative impact to stability.The kinetics was be described by experimental results.
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