Homogeneous Catalytic Wet Air Oxidation Treating Wastewater Containing High Concentration Of Salts And Organic Pollutant In The Continuous Way

More attention has been paid to the problem of environment. Treatment of the wastewater with high concentration of salts and organic pollutant is one of the challenges in the industry.Firstly, catalytic wet air oxidation (CWAO) was been chosen as the way to deal with the model of wastewater in this paper:(1). To examine the stability and treatment efficiency of the fixed bed reactor, it turned out that the COD conversion rate of mono-component (n-butanol) wastewater and multi-components (n-butanol& o-chlorophenol) were 90% and 95% when the temperature was 280 ℃, the system pressure was lOMPa, the flow of liquid and gas was 10 ml/min and 140L/h.(2). Screening the homogeneous catalysts for multi-component simulated wastewater. The optimal catalysts in the fixed bed reactor were Cu2+ & Fe2+ and mass ratio of cation was 1:1 with the cost price and the catalytic activity had been taken into account.(3). The proper condition for the above reaction was as follows:the total concentration of catalyst was 50mg/L, the temperature was 200 ℃, the pressure was 3MPa, and the flow of liquid and gas was 10ml/min and 130L/h. Under this condition, the COD conversion rate of wastewater was 89.12%, and the total conversion rate of o-chlorophenol was nearly 100%.(4). We assessed the effects of different concentration of salts on the efficiency of CWAO in the fixed bed reactor firstly. When the mass concentration of salts ranged from 1% to 5%, the result showed the changed COD conversion rate was less than 5%. It showed that the CWAO technology could be used to deal with wastewater containing high concentration of salts.Then, the kinetics of degradation process of the simulated wastewater in the fixed bed reactor was studied. We established the first order kinetic model of reaction under the condition with excessive air, obtained varied equations of amount of COD in organic wastewater at different temperatures and deduced the apparent reaction rate constant k*. It turned out that the apparent activation energy of degradation was 19.521kJ/mol and the apparent pre-exponential factor lnA was 1.664.Finally, according to the effect of dealing with simulated wastewater containing high concentration of salts, this research tried to degrade the real organic (sodium N-lauroylsarcosinate) wastewater. The self-made flocculant was first used to settle suspended solids on the basis of the wastewater’s character. Then the liquid was pulled into the device of wet air oxidation for treatment. The organic in wastewater was further degraded, and the COD value from the equipment was 1160mg/L. After the homogeneous catalysts were recovered, the outlet water can be absolutely decomposed by the biochemical treatment pool mixed with other non-salt wastewater.