Study On Strengthened Bio-Treatment Of Printing And Dyeing Wastewater By Anaerobic Hydrolysis And Aerobic Oxidation Reaction

Printing and dyeing wastewater from textile and printing industry contains a wide of chemicals which has high color, pH, difficult to be treated and frequent changes. In recent years, as a result of textile dyeing and printing technology progressive and the new dyestuff and auxiliaries appearance, made the ingredient of printing and dyeing wastewater to be more complex, the processing became more and more difficulty. Meanwhile the new sewage disposal standards as well as the strategy of "the energy conservation reduce" also enhanced to the printing and dyeing wastewater disposal request, this is a new challenge for the printing and wastewater disposal system which is building or built.This study took the improvement project of wastewater treatment of Guangdong Province Jiangmen Xinhui Ming Xin elastic fabric Limited Company (hereinafter referred to as the "MingXin Company") as a background. For the company's printing and dyeing wastewater we increased strengthened bio-treatment in the foundation of original wastewater treatment, increased the hydrolytic and aerobic reaction craft, designed simulation biochemistry experiment, simulated the wastewater treatment processes, examined the effect of the processing, and provided the corresponding design parameter for the project application.Before the basic craft of biochemical analog experiment determinated, we carried on the continuous aeration experiment to the Ming Xin Company's wastewater. The experiment indicated: Ming Xin Company's wastewater's CODcr could fall to about 220 mg/L after aeration for approximately 14 h. If the aeration time continued increasing, the CODcr elimination was very limited, still could not attain the discharge requirements. Therefore Ming Xin Company's wastewater could't attain the discharge standards depending on increasing the aeration time alone.The examination results indicated: the anaerobic acidization was very low for the CODcr elimination rate,basically below 20%, had little influence of the hydraulic retention time. For the oxygen reaction process, when the first stage experiment's hydraulic retention time reduced to second stage experiment by 15 hours to 7.5 hours, the CODcr elimination rate by 58% reduced to 52%. Anaerobic acidization's hydraulic retention time played a crucial part in the entire craft running. When the hydraulic retention time, pH, and temperature did't have big difference, the CODcr elimination rate of anaerobic acidization and the entire experiment's processing was more influenced by the CODcr of entering water. It had the same change tendency with entering water CODcr. The aerobic oxidation process which was back of anaerobic acidization was not nearly influenced by the entering water CODcr. In the experimentation,the CODcr elimination quantity of the anaerobic acidization is small, but the CODcr elimination quantity of the aerobic oxidation process is big. This confirmed that the anaerobic acidization which is in front of the aerobic oxidation enhanced the wastewater to be treatmented in biochemistry.For this simulation biochemical experiment, when the anaerobic process's hydraulic retention time was 15 hours, the aerobic oxidation process's hydraulic retention time was 7.5 hours, throwed nutrient suitably which contains N and P to adjust the waste water nutrient structure, the treated water's quality was quite stable, and it could attain the corresponding discharge standards. If N, P nutrient wasn't added, the water quality of treated water would drop, but still could attain the corresponding discharge standards.