【作者】 陈青青；

【导师】 彭党聪；

【作者基本信息】 西安建筑科技大学 ， 环境工程， 2009， 硕士

【摘要】 城市污水处理厂的污泥水包括污泥厌氧消化池排出的上清液、后续浓缩池的上清液和污泥脱水车间排出的脱水滤液,由于其NH₄⁺-N浓度较高,因此,尽管水量仅占污水处理厂总水量的1%～2%,但NH₄⁺-N负荷却占总负荷的15%～25%。通常污泥水被回流至进水口进行再处理,这就造成处理系统的实际NH₄⁺-N负荷高于设计负荷,致使污水厂出水的NH₄⁺-N浓度不能达到相关的排放标准。通过对污泥水单独处理,并富集硝化菌,投加到污水处理系统中,可大大强化污水处理厂的脱氮效率。本研究采用SBR反应器,探讨不同温度（30℃、25℃、20℃）条件下污泥水的硝化效果和硝化菌产率,并运用荧光原位杂交（FISH）技术对所富集的硝化菌的种类和数量进行检测,分析温度变化对其微生物群落结构的影响。主要研究结果如下:（1）污泥水中的COD较难降解,整个试验过程中TCOD和SCOD的平均去除率分别为63.0%和51.3%。系统的硝化性能良好,NH₄⁺-N的平均去除率为99.3%,但是反硝化效率欠佳,TN的平均去除率仅为24.3%,同时获得了25.5%的PO₄^3--p去除效率。反应器运行稳定后,活性污泥结构致密,原生动物活动活跃。污泥沉降性能好,SVI的平均值为70.0mL/g。（2）30℃、25℃和20℃下培养的活性污泥的最大氨氧化速率分别为25.7、40.7、33.4 mgNH₄⁺-N/gVSS·h;最大亚硝酸盐氧化速率分别11.4、20.4、11.8mgNO₂^--N/gVSS·h,25℃时,硝化速率达最大值。随温度降低,硝化菌的内源呼吸速率逐渐减小,表观产率增大,20℃时达最大值0.138 mg nitrifiers/mgN。mobilis)和氨氧化螺旋菌属（Nitrosospira）;25℃和20℃下,氨氧化球菌属分别占氨氧化菌总数量的63%和70%,为优势菌属;氨氧化螺旋菌属分别占19%和1%。检测到的亚硝酸盐氧化菌种类有硝酸杆菌属（Nitrobacter）、硝酸螺旋菌属（Nitrospira）、硝酸球菌属（Nitrococcus）与硝酸刺菌属（Nitrospina gracilis）。25℃和20℃下,硝酸杆菌属分别占亚硝酸盐氧化菌总数量的64%和65%,为优势菌属;硝酸螺旋菌属分别占35%和19%;硝酸球菌属分别占1%和6%;25℃下没有检测到硝酸刺菌属,而在20℃,数量占10%。随温度降低,氨氧化菌和亚硝酸盐氧化菌在总细菌数中所占份额均有所增加,25℃和20℃下污泥中氨氧化菌的含量分别占总细菌含量的15.7%和18.8%,亚硝酸氧化菌分别为12.9%和14.4%。更多还原

【Abstract】 Reject water from municipal wastewater treatment plant（WWTP） is composed of supernatant discharged from the anaerobic digester,sludge thickener tank and sludge dewatering filtrate from sludge dewatering devices.Although the volume of reject water is small（olny 1%～2%of the flow rate）,the nitrogen load is high（15%-25%of total load）.WWTPs in China adopt the methond of recirculating reject water to the influent inlet,which causes the actual nitrogen load of the treatment system higher than the design load,so that there is an incomplete nitrification in WWTP.The reject water could be treated separately to produce a nitrifying biomass for bioaugmentation.nitrifiers would be treated separately in sequencing batch reactor（SBR）,the nitrification performance and nitrifying biomass accumulation at different temperatures（20℃,25℃,30℃）were investigated respectively.Then the type and quantity of nitrifiers cultivated with reject water were investigated by fluorescent in situ hybridization（FISH）,the effect of various temperatures on microbial community was analyzed.The results obtained showed that:（1） There was a low organic curbon removal rate,the everage removal efficiencies of TCOD,SCOD were 63.0%and 55.6%.The conventional activated sludg can achieve a excellent nitrification performance,the average remoal efficiencice of NH₄⁺-N was 99.3%.However there was a bad anti-nitrification ability,the average removal efficiencice of TN was only 24.3%during the experiment. And there was a remove rate of 25.5%with PO₄^3--P.When SBR operated steadily,the activated sludge had a compact structure,there were so many active protozoa that filamentous bacteria were not found.The settleability of sludge is very well and the average SVI was 70mg/L.（2） When temperature was cotrolled as 30℃,25℃and 20℃,The maximum ammonia utilized rate（AUR） of activated sludg were 25.7,40.7,33.4 mgNH₄⁺-N/gVSS.h respectively,and the maximum nitrite utilized rate（NUR） were 11.4,20.4,11.8 mgNO₂^--N/gVSS-h respectively.The nitrification rate was 326.0 mgN/gnitrifiers.h.Observed yield coefficieny(Y_obs) of nitrifiers would increase with temperature drop,there was a maximum as 0.138mg nitrifiers/mgN at 20℃.（3） Ammonia oxidizing bacteria（AOB） includes Nitrosococcus mobilis and Nitrosospira in activated sludge,At 25℃,the percentage of Nitrosococcus mobilis and Nitrosospira in AOB were 63%and 19%,while 70%and 1%at 20℃.Nitrite oxidizing bacteria（NOB） includes Nitrobacter,Nitrospira,Nitrococcus and Nitrospina gracilis. At 25℃,the percentage of Nitrobacter,Nitrospira and Nitrococcus in NOB were 64%,35%and1%while Nitrospina gracilis were not found.Then the percentage of Nitrobacter,Nitrospira,Nitrococcus and Nitrospina gracilis in NOB were 65%,19%,6%and 10%respectively.The percentage of AOB and NOB in total bacteria would increase when the temperature decreases,,at 25℃and 20℃,the percentage of ammonia oxidizing bacteria（AOB/DAPI） in activated sludge were 15.7%and 18.8% respectively,then the percentage of nitrite oxidizing bacteria（NOB/DAPI） were 12.9%and 14.4%respectively.更多还原