| Coking wastewater is in the production of gas, tar, coke and other products generated in the process of coking, which contains mostly nitrogen, phenols, cyanide, sulfide, oil, etc, are toxic refractory organic industrial wastewater treatment very difficult problem of coking wastewater treatment has become the field of environmental protection need to be resolved at this stage is a difficult problem.At present, the widespread using method of coking wastewater treatment in our country is:First, high concentrations of coking wastewater by solvent extraction from phenol and ammonia, after pretreatment of the water mixed with other waste water into the wastewater treatment facilities, by regulation, grease sedimentation, biological treatment processes before being discharged. The process for phenol, cyanide and other easily biodegradable organic compounds have a good treatment effect, but polycyclic aromatic hydrocarbons and heterocyclic compounds such as the treatment effect of refractory organic matter is not ideal, the effluent COD and ammonia nitrogen high concentration, can not meet control requirements of wastewater discharge standards, bring harm to the environment and the human body.In view of the present coking wastewater treatment effect is not the ideal situation, the research uses supercritical water oxidation (SCWO) processing of new technology. Supercritical water oxidation in dealing with high concentrations and hard-degradation waste water has unique advantages, is developed in recent years as a green environmental protection treatment technology. Based on the characteristics of supercritical water as the starting point, this paper expounds the characteristics of SCWO technology at home and abroad, and the research on technology in SCWO reviewed comprehensively reviewed. Based on this, using self-designed SCWO system in coking wastewater treatment plant, COD, cyanide and sulfur in as the main research object, cyanide to its reaction rules were more detailed study, draw the following conclusion:1. SCWO treatment of coking wastewater is better, in the experimental condition, three indicators can be as high as 95% removal rate, indicating that SCWO technology is a highly efficient water treatment technology;2. The single factor experiment, combined with orthogonal test results show that the single factor for SCWO processing coking wastewater in the size of the CODremoval would affect order:retention time> crosses oxygen multiples> system temperature> system pressure, and draw the SCWO technology for the treatment of the coking wastewater optimal process:N=2.5, t=56.34 s, T= 480℃,P=26MPa;3. With hydrogen peroxide as the oxidant, in the system temperature 460℃, reaction pressure of 26MPa, under the conditions of retention time of 34.16s, water under the condition, The removal rate of COD in water increases with the peroxide multiples almost linear relationship.fitting equation is y=21.724+17.726, R2=0.8663,Correlation coefficient R is higher, more than 0.9, but when crosses oxygen increased to 2.5, multiple add to it is little affected removal three indexes;4. For the dynamics of SCWO processing coking wastewater, this experiment used the power exponent equation method,under the conditions of 2.5 times in oxygen,reaction pressure 26MPa,according to the experimental data, it is concluded that the dynamic equation of parameters, the list below:Finally calculated the activation energy dynamic response equation En= 37.993 KJ/mol, refers to the former factor ko= 21.97;5. Analyses the technical application prospect, SCWO for realizing green water processing the application to provide further theoretical basis, finally summarized the SCWO technical engineering application problems, puts forward the corresponding solutions.
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