Experimental Study On Treatment Of The Wastewater From Sugarcane Alcohol Molasses By The Ozone Oxidation And The Activated Carbon Adsorption

The wastewater from sugarcane alcohol molasses contains many organic matters and suspended matters, even pigments. To discharge straightly would be led to serious pollution problems, even destruction of ecological environment. Therefore, it is very necessary to treat validly the wastewater. Guangxi is the biggest province of production sugarcane and alcohol molasses in China. Up to now, the wastewater is a hard nut crack. Even some factories are faced with very serious environmental pollution problems because of it. There are a series of methods about treatment the wastewater, including of oxidation pond, irrigating farms, fermentation, biochemical treatment as well as concentration treatment and so on. However, there is no any ideal method, either to reach discharge standard or not to have highly economic cost. Even some methods can't be done owing to their owner high cost. So it has significant foreground to explore a method that is both feasible in economy and effective in technology. The aim of this thesis is to find a new treatment technique of the wastewater, which includes bothdegradation of the ozone oxidation or the activated carbon adsorption and treatment of Membrane Bioreactor (MBR). This thesis emphatically studied degradation of the wastewater by the ozone oxidation and the activated carbon adsorption. And to find a better pretreatment both them that can improve effect of the latter biotreatment.The wastewater was from the Nanning Sugarcane and Paper Plant. It was degraded by the ozone oxidation and the activated carbon adsorption. The effect of the initial pH of the wastewater, the reactive time, the reactive temperature and the ratio of ozone quantity and the wastewater quantity or the quantity of the activated carbon on the removal efficiencies of Chemical Oxygen Demand (COD) and color in the wastewater was investigated. Based on above results, we could find out the optiomal technical conditions of two treatment methods by the orthogonal experiments. The quick COD microwave-sealed digestion measuring apparatus was adapted to analyzed COD in the wastewater. The model 722 visible spectrophotometer was adapted to analyzed optical density (OD) in the wastewater. And drown a conclusion from experiments was that pH=7 and 560nm wavelength are the optiomal determination parameters. Through the orthogonal experiments, we could find out the optiomal technical conditions of the ozone oxidation that the initial pH of the wastewater is 11.50, the ratio of ozone quantity and the wastewater quantity is 0.270g/mL, the reactive time is 30mins and the reactive temperature is 35 C. And the results of experiments show that the removal efficiencies of COD in the wastewater are 26.4%, and these of color in the wastewater are 92.8%. On the other hand, the optiomal technical parameters of the activated carbon adsorption are as follows: the quantity ofthe activated carbon is 0.083g/mL, the adsorption time is 40mins, the adsorption temperature is 50癈, and the initial pH of the wastewater is 2.50. And the results of experiments show that the removal efficiencies of COD in the wastewater are 25.5%, and these of color in the wastewater are 24.9%. During the course of the ozone oxidation experiments, we found out that strong basic condition is contributed to degradation of COD and color in the wastewater. And strong acid condition, more adsorption time and quantity of the activated carbon are all contributed to degradation of COD and color in the wastewater for the activated carbon adsorption. Comprehensively considering from the removal efficiencies and economy, the ozone oxidation is a better pretreatment than the activated carbon adsorption for the MBR.