味精废水好氧同步硝化反硝化的试验研究

采用SBR处理味精废水,考察了味精废水的可生化性、好氧条件下的同步硝化反硝化以及不同C/N下有机负荷和氨氮负荷的变化.结果表明,对COD的去除率为91.6%～97.2%,对BOD5的去除率>95%,味精废水的BOD5/COD为0.5,说明其可生化性较好,可为反硝化过程提供充足的碳源;试验中存在明显的同步硝化反硝化现象,对氨氮和总氮的去除率分别达到99%、96%;随着进水C/N的降低,有机负荷降低,氨氮负荷升高.     

MBR处理垃圾渗滤液的亚硝酸型硝化反硝化研究

对高浓度氨氮的去除一直是垃圾渗滤液处理中的难点之一，为此利用膜生物反应器（MBR）对渗滤液进行了亚硝酸型硝化反硝化的中试研究。结果表明，当进水氨氮浓度〈1000mg／L、氨氮负荷为0．4kgNH4^＋-N／（m^3·d）时，对氨氮的去除率可达80％～90％。当反应器中的游离氨浓度〉5mg／L时，NO2^- —N的积累率可达80％以上，表明游离氨抑制是实现亚硝酸型硝化反硝化的主要原因。当进水碳氮比〉（2：1）时，对总氮的去除率可达70％左右，对碳源的需求量明显低于传统的硝化反硝化工艺；当进水的碳氮比降至1：1时，对总氮的去除率仅为30％左右。     

高浓度氨氮生活污水对UCT工艺系统的影响及对策

研究了高浓度氨氮城市生活污水对UCT工艺的影响及相应对策。结果表明,采用UCT工艺处理高浓度氨氮城市生活污水,经过较长时间的污泥驯化和运行调节,系统能达到最佳运行状态,CODcrBOD5NH3-N、TN和TP去除率分别达到88．8％,97．2％,96．2％,85．7％和51．1％,TP需要进一步进行物化处理;UCT工艺的脱氮除磷效率较高,对高浓度氨氮城市生活污水基本可以达到理想的处理效果;高浓度氨氮城市生活污水对活性污泥有明显的冲击,污泥驯化培养需要较长的时间;为提高系统的处理效率可增加好氧区的曝气量,但会对活性污泥产生明显的影响,使出水CODcr和SS含量偏高;高浓度氨氮城市生活污水对UCT工艺脱氮除磷效果有明显的影响,好氧区停留时间、曝气量、硝化液回流比和碳源成为影响因素,可在这些方面加以调节。     

双污泥反硝化除磷工艺处理生活污水的中试研究

为了探索双污泥反硝化除磷工艺(A2N工艺)的实际运行效果,采用好氧段为活性污泥法的A2N工艺处理无锡某污水处理厂的曝气沉砂池出水.中试结果表明:A2N工艺对COD、TP、磷酸盐、氨氮具有较好的去除效果,出水平均浓度分别为21.6、0.19、0.04和2.73 mg/L,对COD、TP和氨氮的平均去除率分别为80.8%、89.9%和89.3%;进水TN平均为28.8 mg/L,出水平均浓度为12.6 mg/L,平均去除率为55.95%;设置后曝气池确保了出水磷酸盐和氨氮的达标排放,而且通过吹脱氮气,还提高了反硝化聚磷污泥的沉降性能.     

两段SBR双污泥系统的短程硝化/反硝化除磷研究

针对传统脱氮除磷工艺存在的占地面积大、运行成本高等问题,将短程硝化与反硝化除磷工艺相结合而构建了两段SBR双污泥短程硝化反硝化除磷工艺.在成功启动短程硝化反应器后,亚硝酸盐氮的积累率达到94.23%,系统对氨氮的平均去除率>95%;在以亚硝酸盐氮为电子受体的反硝化除磷菌培养驯化阶段,吸磷率达到了64.44%,同时NO2--N由17.79 mg/L降低为0.05 ms/L,电子受体被完全消耗,基本达到了以NO2--N为电子受体进行反硝化聚磷菌富集的目的.在此基础上,考察了N/P值对系统脱氮除磷效果的影响.结果表明,当N/P为3.0、2.2、1.7时对COD和氨氮的去除效果均较好,对COD的去除率分别为90%、89%、90%,对氨氮的去除率分别为96%、95%和96.7%;当N/P为3.0和2.2时除磷效果良好,平均去除率分别达到了88.5%和91%;而当N/P为1.7时除磷效果明显下降,仅为75.6%.     

分段进水对A2O/MBR组合工艺的影响机制研究

针对现有城市污水处理厂进水碳源不足的问题,根据厌氧释磷和反硝化脱氮对碳源的不同需求,采用分段进水A20/MBR组合工艺,研究分段进水对其影响机制.结果表明:分段进水优化了进水碳源在厌氧池和缺氧池中的分布,对TN的去除率随分配到缺氧池流量的增加而增大.当缺氧池分配流量增加到0.35Q时,对总氮的平均去除率达到56.8%,较单点进水工况提高了14.0%.分段进水对去除COD的影响不大,对COD的去除率稳定在82.3%～85.7%.由于进水中溶解性磷浓度较低,磷主要以胶体态和悬浮态形式存在,通过超滤膜的截留作用,组合工艺对TP的平均去除率稳定在90%以上;不过采用分段进水后,组合工艺对TP的平均去除率会略有下降.     

HRT和C/N值对生物膜SND及N_2O产生的影响

采用连续流生物膜反应器处理模拟生活污水,考察了HRT(分别为5.0、6.5、8.0、9.5和11.0 h)以及C/N值(分别为2.0、3.5、5.0、6.5、8.0)对同步硝化反硝化(SND)脱氮效果的影响,并探讨其一氧化二氮(N2O)的释放情况。结果表明,当HRT=8.0 h时最有利于实现同步硝化反硝化,且处理效果最佳,对COD和氨氮的去除率均在90%以上,对总氮的去除率为68.2%,同步硝化反硝化率为80.9%。HRT=6.5 h时,N2O释放量最高,此时转化率为3.44%。较高的C/N值有利于N2O的减量化控制,当C/N值=2.0时系统中N2O释放浓度最高。但综合能耗和去除效率等因素,将C/N值控制在6.5左右较为合理,此时对COD的去除率在90%以上,对氨氮的去除率在85%以上,对总氮的去除率为71.2%,N2O转化率为1.07%。     

分段进水SBR处理高浓度氨氮废水的中试研究

对传统分段进水SBR工艺进行改进,增加球形悬浮填料和搅拌措施,并建立中试系统,考察系统对高浓度氨氮废水的处理效果以及温度对脱氮效果的影响。结果表明:该工艺对高浓度氨氮废水的处理效果良好,在进水COD为580～970 mg/L、NH_4~+-N为90～257 mg/L的条件下,对COD、NH_4~+-N和TN的去除率基本在80%、80%和70%以上。水温对系统处理效果的影响显著,水温与比氨氧化速率和比反硝化速率呈显著的正相关性。分段进水SBR工艺可充分利用原水中的有机物作为反硝化碳源,在节能降耗的前提下,可实现废水的深度脱氮处理。     

基于碳源需求的A~2/O工艺分段进水研究

针对现有A2/O工艺难以稳定实现同步生物脱氮除磷的问题,根据反硝化脱氮和厌氧释磷对碳源的不同需求,采用分段进水的方法,以期提高其脱氮除磷效果。外加乙酸碳源的试验结果表明,在厌氧段投加碳源不能有效提高后续缺氧段的反硝化效果。因此根据反硝化脱氮和厌氧释磷对碳源的不同需求,建立了分段进水的分配模型,以提高A2/O工艺的反硝化速率和释磷速率。A2/O工艺中试采用预缺氧段、厌氧段和缺氧段进水比例分别为15%、50%和35%的方法,结果表明,系统平均出水总氮和总磷分别为15.3和0.41 mg/L,稳定达到了GB 18918—2002的一级B排放标准;对总氮和总磷的去除率分别达到了68.5%和93.2%,比厌氧段单点进水分别提高了15.1%和16.6%。     

曝气生物滤池对晚期垃圾渗滤液的短程脱氮研究

采用固定化微生物曝气生物滤池（I—BAF）对晚期垃圾渗滤液进行了短程脱氮试验研究。经过微生物固定化和硝化茵培养后，通过控制溶解氧等条件可使反应器（I—BAF1）实现稳定的亚硝化，亚硝化速率平均值是硝化速率的21．5倍，对氨氮的去除率达到90％左右，且氮主要是由同步硝化反硝化作用去除的；与全程脱氮相比，短程脱氮对总氮的去除率更高，其COD主要通过反硝化作用去除；以NaAc为外加碳源，提高C／N值为1．6～2，2时，对总氮的去除率可达60％以上，继续提高C／N值至4．5时，硝化茵因受到异养菌的抑制而活性降低，导致脱氮效果变差。当将两级I—BAF（I—BAF2充分曝气）与Fenton工艺联用时，对COD、氨氮和总氮的去除率分别为95．1％、99．1％和73．8％。     

Heterotrophic activity compromises autotrophic nitrogen removal in membrane-aerated biofilms: results of a modeling study

A 1-d multi-population biofilm model was constructed to study the effect of heterotrophic activity on completely autotrophic ammonium (NH4+) removal in membrane-aerated (counter-diffusion) versus conventional biofilm systems (co-diffusion). Growth of heterotrophic bacteria (HB) was supported either solely by biomass decay products or by organic carbon (as chemical oxygen demand (COD)) in the influent. Three scenarios were considered: influence of HB growing on biomass decay products on steady-state performance (total nitrogen (TN) removal efficiency); influence of the influent COD/N ratio on steady-state performance (supplying COD in the influent); and impact of dynamic changes in the influent COD/N ratio on TN removal efficiency. The results revealed that the TN removal efficiency in the counter-diffusion biofilm was significantly different when HB were included in the simulations at NH4+ surface loads of LNH4>2.7 g - N m(-2) d(-1). Influent COD significantly altered the microbial community composition in the counter-diffusion biofilm and anaerobic NH4+ oxidation could not be sustained at COD/N>2. The co-diffusion system, however, was less affected and more than 50% of the TN removal originated from anaerobic NH4+ oxidation at those ratios. Perturbation experiments showed that step increases to influent COD/N ratios of 2 or higher over a period of 50 d or longer caused a loss of anaerobic NH4+ oxidation capacity which could not be regained within a reasonable time frame (>1000 d) in the counter-diffusion system. In contrast, simulating a 1-d sloughing event only caused a disturbance of 200 d although a maximum biofilm loss of 90-95% occurred. These results clearly indicate the importance of heterotrophic activity in autotrophic N removal biofilms, especially in counter-diffusion systems where they may compromise N removal capacity.     

一体化IMBR处理低碳城市污水的脱氮研究

在进水C／N为3、4、5和HRT为4、8、12h的条件下,研究了一体化间歇曝气膜生物反应器（IMBR）对COD、NH4^＋-N、TN的去除效果。研究表明,在低C／N条件下,IMBR仍有很好的脱氮效果,出水COD、TN、NH4^＋-N达到了GB18918--2002标准的一级A标准;随着C／N的增加则对各污染物的去除率都有所升高;随着HRT的延长,IMBR对COD、TN、NH4^＋-N的去除率有较大的提高,但当HRT〉8h后,随着HRT的延长,对COD的去除率反而略有下降。     

氮磷比对三维电极/生物膜反应器反硝化效果的影响

研究了连续流三维电极/生物膜反应器在不同氮磷比(N/P)下的反硝化性能。结果表明:N/P值对去除NO3--N的影响不大,但对出水NO2--N浓度有明显影响。在N/P值由5∶1增大至100∶1的过程中,对NO3--N的去除率介于59.2%～71.6%之间。当N/P值为10∶1时,对NO3--N的去除率最高达到了71.6%,出水NO3--N为8.53 mg/L。当N/P值为10∶1时,出水NO2--N浓度最低为0.27 mg/L;当N/P值为100∶1时NO2--N的积累最为严重,NO2--N生成量最高达到了1.76 mg/L。N/P值还对NH4+-N的产生有明显影响,N/P值从5∶1增至100∶1的过程中,NH4+-N生成量由4.50 mg/L逐渐减小至0.26 mg/L。当N/P值为(5∶1)～(50∶1)时,反应器具有较好的除磷功能;但当N/P值为100∶1时,出水TP浓度高于进水TP浓度。     

固定化氨氧化菌短程硝化的启动研究

采用亲水性玻璃态单体,应用辐射技术制备生物相容性高分子共聚物载体,使用固定化细胞增殖技术对氨氧化菌进行固定化,并以流化床为生物反应器,采用SBR运行方式对人工配水进行短程硝化的启动研究.结果表明:当进水氨氮浓度为100、75、50和25mg/L时,对氨氮的的去除率分别为98.6%、99.1%、98.8%和99.8% ,亚硝化率分别为 98.6%、94,5%、95.2%和94.7%:对氨氮的去除速率由开始时的10.6mg/(L·d)提高到25.7mg/(L·d),耗氧速率(OUR)则由0.37mg/(L·d)提高到1.12mg/(L·d).可见,该方法具有启动速度快、亚硝化程度高、容易控制等优点.     

生物膜电极工艺去除微污染源水中氨氮的研究

采用生物膜电极工艺去除微污染源水中的氨氮.在好氧区利用金属阳极电解产氧,在硝化细菌的作用下使氨氮转化为硝酸盐氮或亚硝酸盐氮;在缺氧区利用碳棒作为阴极电解产氢,实现反硝化脱氮.试验结果表明:C/N、电流强度、氨氮浓度、进水流量等对去除总氮均有影响;在流量为3 L/d、无外界供氧、电流强度为19.5 mA、C/N为1的条件下,当进水COD为10 mg/L、氨氮为7 mg/L时,对总氮的去除率可达95.6%,显著改善了水质.     

Simultaneous organic and nitrogen removal from municipal landfill leachate using an anaerobic-aerobic system

An anaerobic-aerobic system including simultaneous methanogenesis and denitrification was introduced to treat organic and nitrogen compounds in immature leachate from a landfill site. Denitrification and methanogenesis were successfully carried out in the anaerobic reactor while the organic removal and nitrification of NH4+,-N were carried out in the aerobic reactor when rich organic substrate was supplied with appropriate hydraulic retention time. The maximum organic removal rate was 15.2 kg COD/m3 d in the anaerobic reactor while the maximum NH4+-N removal rate and maximum nitrification rate were 0.84kg NH4+-N/m3/d and 0.50kg NO3--N/m3/d, respectively, in the aerobic reactor. The pH range for proper nitrification was 6-8.8 in the aerobic reactor. The organic compounds inhibited nitrification so that the organic removal in the anaerobic reactor could enhance the nitrification rate in the following aerobic reactor. The gas production rate was 0.33 m3/kg COD and the biogas compositions of CH4, CO2, and N2 were kept relatively constant, 66-75, 22-32, and 2-3%, respectively.     

Simultaneous carbon and nitrogen removal from high strength domestic wastewater in an aerobic RBC biofilm

High strength domestic wastewater discharges after no/partial treatment through sewage treatment plants or septic tank seepage field systems have resulted in a large build-up of groundwater nitrates in Rajasthan, India. The groundwater table is very deep and nitrate concentrations of 500-750 mg/l (113-169 as NO3(-)-N) are commonly found. A novel biofilm in a 3-stage lab-scale rotating biological contactor (RBC) was developed by the incorporation of a sulphur oxidising bacterium Thiosphaera pantotropha which exhibited high simultaneous removal of carbon and nitrogen in fully aerobic conditions. T. pantotropha has been shown to be capable of simultaneous heterotrophic nitrification and aerobic denitrification thereby helping the steps of carbon oxidation, nitrification and denitrification to be carried out concurrently. The first stage having T. pantotropha dominated biofilm showed high carbon and NH4(+)-N removal rates of 8.7-25.9 g COD/m2 d and 0.81-1.85 g N/m2 d for the corresponding loadings of 10.0-32.0 g COD/m2 d and 1.0-3.35 g N/m2 d. The ratio of carbon removed to nitrogen removed was close to 12.0. The nitrification rate increased from 0.81 to 1.8 g N/m2 d with the increasing nitrogen loading rates despite a high simultaneous organic loading rate. However, it fell to 1.53 g N/m2 d at a high load of 3.35 g N/m2 d and 32 g COD/m2 d showing a possible inhibition of the process. A simultaneous 44-63% removal of nitrogen was also achieved without any significant NO2(-)-N or NO3(-)-N build-up. The second and third stages, almost devoid of any organic carbon, acted only as autotrophic nitrification units, converting the NH4(+)-N from stage 1 to nitrite and nitrate. Such a system would not need a separate carbon oxidation step to increase nitrification rates and no external carbon source for denitrification. The alkalinity compensation during denitrification for that destroyed in nitrification may also result in a high economy.     

分段进水A/O工艺运行优化研究

基于Stella 9.0.1软件建立分段进水A/O工艺的ASM3水处理模型,并对模型进行简化,引入反映污泥中异养菌和自养菌活性的参数PXH和PXA。在HRT=10 h、VA/VO=2/6、R=75%及三级进水分配比N1∶N2∶N3=3∶4∶3的工艺状态下,由实测数据得出PXH和PXA的校正值分别为0.8 gCOD/gMLSS和0.05 gCOD/gMLSS。通过校正后的模型讨论了各种操作条件对出水COD、NH4+-N及NO3--N的影响。结果表明:HRT是影响出水COD浓度的最主要因素;增大污泥回流比R及缺、好氧池的容积比VA/VO都会减小出水NO3--N浓度;为保证出水的NH4+-N浓度较低,除提供充足的溶解氧和较长的水力停留时间外,第三段的进水分配比也不宜过大。综合考虑,较优的工艺参数值为HRT=14 h、R=50%、VA/VO=2/6及N1∶N2∶N3=1∶2∶1。将该参数运用于实际操作中,最终使系统对COD的去除率从77.6%提高到了94.1%,对TP的去除率也从30.2%提高到81.2%,实现了同步脱氮除磷。     

味精废水生物除碳脱氮动力学特性的研究

为优化某味精废水处理工程的操作,研究了其除碳脱氮动力学特性.结果表明,对COD的最大比去除速率为0.110 kgCOD/(kgVSS·h),最大容积去除速率与实际容积负荷之比为17.28～21.12,最大比去除速率与实际污泥负荷之比为13～21,饱和常数KS为202 mgCOD/L;对氨氮的最大比去除速率为0.014 1 kgNH4+-N/(kgVSS·h),最大容积去除速率与实际容积负荷之比为8.86～11.25,最大比去除速率与实际污泥负荷之比为7～11,KS为19.1 mgNH4+-N/L,表明该工程去除COD和氨氮的潜力还很大,容易实现达标排放.当以葡萄糖为碳源时,对硝态氮的最大比去除速率为0.014 0 kgNO3--N/(kgVSS·h),KS为13.5 mgNO3--N/L;当以醋酸盐为碳源时最大比去除速率为0.024 4 kgNO3--N/(kgVSS·h),KS为12.0 mgNO3--N/L,表明醋酸盐比葡萄糖更有利于提高反硝化速率和强化脱氮效果.     

改良型SBR工艺对奶牛场废水中抗生素的去除效果

奶牛场废水中的有机物和抗生素对其还田利用不利,为此,采用带缺氧区的推流式SBR(简称改良型SBR)工艺处理干清粪条件下间歇产生的奶牛场废水,重点考察其对抗生素的去除效果。结果表明,当进水COD、NH4+-N、TN、TP浓度分别为1 234~4 696、768~1 365、880~1 370、5.62~12.02 mg/L时,经改良型SBR工艺处理后,出水COD可降至401~544 mg/L、NH4+-N始终低于10mg/L,TN平均损失率为22.38%,TP基本没有被去除。奶牛场废水中磺胺类和β-内酰胺类抗生素总浓度为3.84~4.48μg/L,改良型SBR工艺对其总去除率可达到72.97%~90.82%,且对10种较高浓度的磺胺类抗生素(每种添加浓度均为50μg/L,共计500μg/L)也有很好的去除效果,去除率可达95.75%~95.97%。生物降解是奶牛场废水中磺胺类和β-内酰胺类抗生素的主要去除途径,另外,磺胺类抗生素的去除与其分子结构中S—N键的断裂有重要关系。在不影响COD去除效果的条件下,调整反应器的混合液回流量或进水量均可减少碱度投加量,从而降低运行成本。