低温UASB处理青霉素综合废水及动力学分析

UASB treatment penicillin comprehensive wastewater and dynamic analysis at low temperature

采用逐步降温法启动上流式污泥床反应器(UASB)并对其过程做动力学分析。UASB反应器采用逐渐提高进水COD负荷的方式在25℃进行启动,当COD去除率达到70%完成启动。启动完成后,降低温度运行反应器,在20℃时COD的去除率达到65%左右。在25℃条件下,出水氨氮浓度增加,总氮浓度有增加趋势,随后出水总氮浓度降低;在20℃负荷提高和稳定时期,出水的氨氮浓度逐渐降低,总氮浓度逐渐升高。建立低温条件下厌氧处理高浓度有机废水的动力学模型,分析结果看出20℃运行阶段的基质比降解速度高于25℃阶段基质比降解速度,在20℃条件下厌氧污泥活性最大,污泥性能最佳。推测原因,可能是由于25℃时进水浓度较高,且废水中含有大量抑制性物质(1.1 mg·L^(-1)),较大影响了微生物的降解速率、而在20℃时进水浓度降低,废水中的抑制性物质也有所降低,为0.75 mg·L^(-1)。

The up-flow anaerobic sludge bed reactor（UASB） is started by step-down temperature method and analyzed by the dynamic kinetics change. By increasing the COD loading of the input water gradually,the startup of the UASB reactor at 25 ℃ was achieved and the COD removal rate was 70%. When the reactor was operated at lower temperature（20 ℃）,the removal rate of COD was reduced to approximately 65%. At 25 ℃,the ammonia nitrogen concentration of effluent was increased,while the total nitrogen concentration increased initially and then followed by a decrease. At 20 ℃,the concentration of ammonia nitrogen was decreased and the concentration of total nitrogen was increased. The kinetic model of anaerobic treatment of high concentration organic wastewater under low temperature was established,showing that the substrate degradation rate of 20 ℃ was higher than that of 25 ℃,and the highest activity of anaerobic sludge was observed at 20 ℃. The reason was concluded that the concentration influent water at 25 ℃ was higher than that at 20 ℃ and that the wastewater contained a large number of inhibitory substances（inhibition of 1. 1 mg·L^-1） at 25 ℃,while at 20 ℃,the water concentration was decreased and the inhibitory substance in wastewater was also reduced（inhibition of 0. 75mg·L^-1）.