微孔曝气变速氧化沟反硝化除磷与硝化性能试验研究

发布时间：2018-03-26 13:29

  本文选题：微孔曝气变速氧化沟　切入点：脱氮除磷　出处：《西安建筑科技大学》2015年硕士论文

【摘要】：采用微孔曝气变速氧化沟中试系统处理城市污水,研究其对污水中氮、磷和有机物的去除效果,同时采用静态试验的方法考察该系统内活性污泥的反硝化除磷与硝化性能,并分析进水C/N和C/P对脱氮除磷的影响、不同电子受体的吸磷过程对比及温度对污泥硝化速率的影响。试验结果表明:(1)微孔曝气变速氧化沟中试系统对城市生活污水中氮、磷和有机物有很好的去除效果,稳定运行期间中试系统对进水中的COD、NH4+-N、TN及TP的平均去除率分别为92%、96.9%、81.8%和94.5%;出水COD、NH4+-N、TN和TP的平均浓度分别为30.7mg/L、1.17mg/L、11.4mg/L和0.34mg/L。各污染物指标除TP外,均达到我国城市污水处理厂污水排放标准(GB18918-2002)一级A排放标准,TP的达标率为84%。(2)进水C/N和C/P比对微孔曝气变速氧化沟中试系统脱氮除磷有影响,进水C/N比为5~6时,系统取得更好的脱氮除磷效果;进水C/P比与系统脱氮没有明显的相关性;进水C/P比为60~80时,系统取得更好的除磷能力。(3)微孔曝气变速氧化沟中试系统存在明显的反硝化除磷现象,系统内活性污泥中DPB占PAOs的61%。反硝化吸磷过程中,以氧、硝酸盐和亚硝酸盐为吸磷过程的电子受体时,吸磷速率大小依次为:氧硝酸盐亚硝酸盐。且反硝化除磷过程中,硝酸盐、亚硝酸盐的消耗量与吸磷量之间的化学计量关系(P吸收/N消耗,质量比)分别为0.96和0.65。(4)微孔曝气变速氧化沟中试系统具有较好的硝化性能,活性污泥AUR和NUR分别为3.89~5.59 mg-N/(g·VSS·h)和2.98~6.93 mg-N/(g·VSS·h),平均值分别为4.57 mg-N/(g·VSS·h)和4.63 mg-N/(g·VSS·h)。(5)温度对微孔曝气变速氧化沟中试系统活性污泥硝化能力影响大,系统污泥的AUR与NUR值随温度的升高呈逐渐增大的趋势。15℃以下时,中试系统活性污泥中AOB和NOB活性急剧下降,生物硝化能力降低。并且,温度低于10℃时,污泥的硝化能力明显降低。(6)针对试验期间由于回流系统出现故障引发的污泥浓度低、硝化细菌数量大幅减少、出水氨氮高的现象,采取降低进水量、加大曝气量、减少排泥量等措施恢复污泥的硝化能力,调试100d后,中试系统污泥硝化性能完全恢复,为实际工程中活性污泥系统的运行与调控提供参考。(7)应用ASM2d简化模型对微孔曝气变速氧化沟中试系统生物硝化过程进行模拟,硝化模型的模拟结果变化趋势与实际运行过程基本吻合,浮动范围为-0.84~2.59mg/L。
[Abstract]:In this paper, a pilot system of microporous aeration variable speed oxidation ditch was used to treat municipal sewage, and the removal efficiency of nitrogen, phosphorus and organic matter in sewage was studied. At the same time, the denitrifying phosphorus removal and nitrification performance of activated sludge in the system were investigated by static test. The effects of influent C / N and C / P on denitrification and phosphorus removal, the comparison of phosphorus absorption process of different electron receptors and the effect of temperature on sludge nitrification rate were analyzed. Phosphorus and organic matter were removed very well. The average removal rates of COD NH 4 N N N and TP in influent during steady operation were 92.2% and 94.5%, respectively. The ratio of C / N and C / P in influent water is 84 / 2). The ratio of C / N and C / P in influent water is affected by denitrification and phosphorus removal in the pilot system of micropore aeration variable speed oxidation ditch. The ratio of influent C / N is 56-6. The system achieved better denitrification and phosphorus removal effect; the influent C / P ratio had no obvious correlation with the system denitrification; when the influent C / P ratio was 60 ~ 80, A better phosphorus removal capacity was obtained in the system. (3) there was obvious phenomenon of denitrifying phosphorus removal in the pilot system of micropore aeration variable speed oxidation ditch. The DPB in activated sludge accounted for 61% of PAOs in the system. Oxygen was used in denitrification and phosphorus absorption process. When nitrate and nitrite are electron receptors in phosphorus absorption process, the order of phosphorus uptake rate is nitrite. The stoichiometric relationship between the consumption of nitrite and the amount of phosphorus uptake. The ratio of P absorption to N consumption and mass ratio are 0.96 and 0.65.4respectively. The pilot system of micropore aeration variable speed oxidation ditch has better nitrification performance. The AUR and NUR of activated sludge were 3.89 ~ 5.59 mg-N/(g VSS (h) and 2.98 ~ 6.93 mg-N/(g VSS h respectively, the average values were 4.57 mg-N/(g VSS h) and 4.63 mg-N/(g VSS h 路h) respectively. The nitrification capacity of activated sludge was greatly affected by the temperature of 4.63 mg-N/(g VSS. 5) in the pilot system of micropore aeration variable speed oxidation ditch, the nitrification capacity of activated sludge was greatly affected. The AUR and NUR values of sludge increased gradually with the increase of temperature. Below 15 鈩，

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