Study On The Treatment Of Synthetic Detergent Wastewater Using The Technology Of Anaerobic Biofilter And Biological Contact Oxidation Process

The composition of synthetic detergent wastewater which was produced by Xi'an Nanfeng Daily Chemical Plant, is very complicated, and the content of organic matter is high. The wastewater contains a lot of linear alkyl benzene sulfonate (LAS), which is hard to be biodegradable, and the color is tan, partial alkaline, multi-bubble. It has a certain toxicity, and has a greater impact for the the water environment. Furthermore, it also has a strong foaming and emulsifying properties, so the treatment is very diffcult. As for the properties of LAS, investigations had been performed on biodegradability of synthetic detergent firstly , and emphases had been put on experimental analysis on Anaerobic Biofilter . During the proess of hydrolytie acidifieation, big molecules had been divided into small molecules , and unbiogradable substances were also converted into biodegradable substances in the wastewater , so as to lay the foundation for the aerobic biological treatment of the follow-up. On this basis, deside to adopt the two-stage membrane model of AF anaerobic biological filter - aerobic biological contact oxidation Joint Process to treat wastewater.The two-stage membrane experiment showed that AF operated in the conditions of HRT=24h and temperature 32±2℃, the macromolecules organic pollutants had been degraded effectively ,and the removal rate of LAS and COD can be up to 50% and 30% respectively. The ration of BOD/COD had been increased from 0.3 to 0.5 around, and the biodegradability of wastewater improved greatly. Aerobic biofilter operated in the conditions of LAS<40mg/L, HRT=12h and DO=4-5mg/L, the final effluent of comprehensive biochemical treatment is COD<40mg/L and LAS<5mg/L, reaching I-class criteria specified in Integrated Wastewater Discharge Standard(GB 8978-1996). In practice, the basic national policy of protecting the ecology and the environment, which as the strategy of sustainable development had been executed well.The two-stage membrane joint technology provided a reasonable and reliable technology programmes and technical operating parameters for industrial application, and deduced the matrix degradation dynamic model of aerobic biological contact oxidation treatment LAS: 0.72( 0.3288) K S=37.69mg/L, and the coefficient R2=0.9879。...