| In this dissertation, the current treatment technologies of molasses alcohol wastewater are reviewed. The characteristics of the Catalytic Wet Air Oxidation (CWAO), the Supercritical Water Oxidation (SCWO) and the Catalytic Supercritical Water Oxidation (CSCWO), with their study status in the treatment of organic wastewater are elaborated. And then, according to the characteristic of molasses alcohol wastewater, a new technique for treating the molasses alcohol wastewater, Catalytic Subcritical Water Oxidation (CSWO), is put forward and the basic study on the application of CSWO is carried through. The content and conclusion of the research are listed below.1. The characteristic of molasses alcohol wastewater is analyzed. The results are as follows: molasses alcohol wastewater is a kind of high concentration acid organic wastewater, and there is a great quantity of heat to be produced, which can maintain the heat required by the reaction, when it is in the process of CSWO. At the temperature of 110℃, it was found that some organics polymerized and at the temperature of 167℃, some organics were decomposed to produce carbon. When there is oxygen, it won't polymerize and precipitate carbon over the temperature of 240℃. The acidity of the wastewater should be adjusted and the suspended solids should be eliminated before the CSWO in order to avoid the erosion of the reactor by acid substances.2. The neutralization-sedimentation treatment of the molasses alcohol wastewater is researched. Firstly, the wastewater was neutralized by cream of lime to adjust the pH value to 8, and then the suspended solids were flocculated and precipitated by the anionic polyacrylamide (PHP-2) or the composition of PHP-2 and poly aluminum chloride (PAC). The best operation parameters were: the chemicals feeding quantity of PHP-2: 0.9mg/L wastewater, the time of stirring: 6 min, the speed of stirring: 200rpm. The suspended solids were precipitated in 20min. Furthermore, when the PAC was added into the system and the PAC feeding quantity amounted 30mg/l wastewater, it acquired the best effect and the suspended solids were precipitated in 5~7min.3. The catalysts of CSWO are investigated. The result shows that the oxides of copper and manganese have the obvious catalytic effect on the oxidation of the molasses alcohol wastewater. And the effect of the composite catalyst, CuO /MnO2/γ-Al2O3, is better than the single catalyst. The optimal conditions to prepare the composite catalyst are: the aging temperature: 60℃, the aging time: 8h, the calcination temperature: 600℃, and the calcination time: 8h. The ratio of Cu, Mn and γ-Al2O3 is 2∶1∶8.4. The affecting factors of treatment of the molasses alcohol wastewater by CSWO using the CuO/MnO2/γ-Al2O3 as catalyst are studied. The result shows that, the removal ratio of CODCr can be improved by increasing the concentration of oxygen, reaction temperature, reaction time and the quantity of catalyst, in which, the reaction temperature and time have the most distinct effect. The effect of concentration of oxygen becomes unconspicuous when the actual quantity of oxygen exceeds 4.7 times of theoretic oxygen. The removal ratio would also be improved by increasing the quantity of catalyst when the concentration of catalyst is below 10mg/L, but the effect would be unnoticeable when the concentration exceeds 10mg/L. So the optimum of the dosage of the catalyst is 10mg/L wastewater.5. The kinetics of treatment of molasses alcohol wastewater by CSWO is studied. The study shows that, the reaction order is 0 and 1 for oxygen and CODCr, respectively. When we choose CuO/MnO2/γ-Al2O3 as catalyst and the actual quantity of oxygen exceeds 4.7 times of theoretic oxygen in the process of treatment of molasses alcohol wastewater by CSWO, the activate energy is 5.36×104J/mol and preexponential factor is 6.74×103min-1.
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