Application of ozone oxidation technology in sewage treatment

Wang Yu et al. studied the application of the new technology of high frequency ceramic surface discharge ozone to the treatment of printing and dyeing wastewater. When the reaction contact time is 10h and pH value is 7-8, the COD removal rate reaches 86.6% and the decolorization rate reaches 98.4%. When ozone is used for decolorization, pH≤7 should be controlled, under this condition, the decomposition rate of ozone can be weakened and the generation rate of OH· can be increased, so as to improve the utilization rate of ozone.

According to the experiment of using ozone to oxidize the comprehensive wastewater of a branch plant of Renault Automobile Manufacturing Company in France, the ozone can be used to improve the biodegradability of the comprehensive wastewater of automobile manufacturing plant. When the gas production is controlled at about 16 L /h, the ozone supply is 1 kg/h, and the pH is 10, after 2 h ozone oxidation treatment, the COD removal rate of the effluent reaches 60%.

In recent years, ozone is also used for the in-depth treatment of urban domestic sewage, the amount of ozone is generally 10 ~ 20 mg/L, the contact time is 5 ~ 20 min, which can reduce COD by 40%, BOD by 70%, SS by 60%, ammonia nitrogen by 20%, carcinogens by 80% and chroma by 90%.

Japan has developed a fine ozone bubble sewage treatment device, which has been successfully applied. The particle size of the fine ozone bubble produced by the device is extremely small, the diameter is only 10 ~ 100μm, the contact area of the bubble and the wastewater has been increased by 2 000 ~ 4 000 times, the solubility of ozone has been increased by 5 times, and the ozone has been fully utilized, and it has played a good stirring role. Due to the improved efficiency and reduced cost, the device has been used for wastewater treatment in food, animal products and aquatic products processing plants.

With the development of ozone technology application, the research and application of ozone technology has formed an independent industry in the world, and its application prospect is very broad.