| Nowadays it is one of the difficult problems in our country and abroad wastewater treatment fields, that how to treat the chemical fibre cotton pulp mill wastewater economically and efficiently. The paper dealed with constructed industrial treatment equipment, which using the two -phase anaerobic -aerobic SBR combined technology, through the full -scale plant test, estimated the kinetic constants and operational parameters of the key unit equipments in the treatment system, in order to provide some referable grounds for the study on the optimal process.Through the project investigation, We confirmed the following problem existing in the wastewater treatment:The VSS/SS rate of the sludge in the anaerobic hydrolytic tank was low, as well as the acidified rate, ;(2) the operational hydraulic loading rate and volume loading rate in UBF were both lower than the design requirement, in addition, the active sludge concentration and the removal rate in the reactors were Mow, too;The active sludge concentration in the aerobic SBR system was a bit high, but the VSS/SS rate and removal rate is low, furthermore, the settling property of the sludge is not ideal;There were a set of operational and controlling parameters in the biochemical treatment system, which need optimize and improve further.Highlighting to counter the main problem in the treatment system, we put forward the contents of the study:through the process adjustment and full-scale plant test, estimation of the kinetic constants in the two-phase anaerobic system, comparing with those of the similar industrywastewater;the determination of the aerobic kinetic constants;(3)the research of the kinetic design method on SBR, and comparing with the results of the volume loading design method.The study strenched in two aspects, the two-phase anaerobic system and the aerobic SBR system. For the former, aim at the unsolved problem, we were engaged in the process adjustment and full-scale plant test. The content included:the adjustment of the sludge return rate in the hydrolytic tank;effluent return and sludge wastage in UBF. When the system remained a stable state, we estimated the biochemical kinetic constants in the unit reactors, on the base of the project investigation, and compared with those of the similar industry wastewater (pulp and paper mill wastewater). Finally, we discussed and analysed the operational results, preparing for the optimal research on the system.For the aerobic SBR system, we should maintain the system to be steady through strengthening the operation management. According to the batch stirred tank reactor (BSTR) theory and biochemical kinetic equation, we determined the kinetic constants in SBR unit by full-scale test, and compared with those of the similar industry wastewater (pulp and paper mill wastewater). Then we started to the process design according to the SBR kinetic model, and compared with the result of the volume loading design method.Primary conclusion:1. According to the operational data, we estimated the kinetic constants in anaerobic hydrolytic tank and UBF. For the hydrolytic tank, it yielded values of 2. 8 day-1 for VM, 2824mgCODcr/l for Ks, 0.18mgVSS/mgCODcr for Y, 0.088 day-1 for Kd. For UBF, it yielded values of 0.28 day-1 for Vmax, 635mgCODcr/l for Ks, 0. 15mgVSS/mgCODcr for Y, 0.011 day-1 for Kd. Calculated by the corrective formula, we found the constants, such as Kd and V? was remarkably influenced by the naturally changedwastewater temperature(27-32), their extents were 15%-101% and 21%~101%, respectively. We determined the kinetic constants of SBR on the full-scale plant.It yielded values of 0. 70-0. 91mgBOD5/mgVSS day for V,15.5-20. 4mgBOD5/l for Ks, 0. 66-0. 69 mgVSS/mgBOD5 for Y, 0.031-0.041 day"1 for Kd) 0. 52-0. 74mgCODcr/mgVSS day for V ,9.3-14. 2mgCODcr/l for Ks' , 0. 38-0. 45 mgVSS/ mgCODcr for Y',0.021-0. 029 day-1 for K .Calculated by the corrective formula,we found the constants, such as Kd K-V and V was remarkably influenced by the naturally changed wastewater temperature(27-31),t...
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