低负荷下厌氧氨氧化处理养殖废水的启动研究

厌氧氨氧化作为新型生物脱氮技术其关键在于如何实现厌氧氨氧化反应的启动,现有研究多以模拟废水为研究对象,本文以猪场废水为对象的研究,利用ASBR为反应器,接种反硝化污泥培养厌氧氨氧化细菌,在NH+4-N与NO-2-N浓度均为100 mg/L的条件下,运行125 d,经历启动初期、过渡期、系统稳定运行期三个阶段,厌氧氨氧化反应器中NH+4-N的去除率达91.70%,NO-2-N去除率92.0%;NH+4-N的容积负荷为36.90 mg/L.d,NO-2-N的容积负荷为37.55 mg/(L.d),成功实现了厌氧氨氧化反应器的启动。该研究成果对厌氧氨氧化技术在工程实践的应用具有重要的指导意义。     

亚硝酸型硝化-厌氧氨氧化联合工艺处理"中老龄"垃圾渗滤液

亚硝酸型硝化和厌氧氨氧化有机结合构成的新型全程自养生物脱氮技术为处理高氨氮和低C/N的"中老龄"渗滤液提供了新的思路.主要针对系统内部能否实现稳定的亚硝酸氮自给和厌氧氨氧化反应器的启动这两个关键条件进行研究.结果表明,在氨氮负荷率(ALR)为0.069～0.284 3 gNH3-N/(gVSS·d)条件下,前置亚硝酸型硝化反应器(SBR)能实现稳定的亚硝酸氮积累,出水NO-2-N/NH3-N在1.45左右,NO-2-N/NO-x-N大于90%.而且,接种前置SBR中具有硝化活性的污泥用作厌氧氨氧化反应器(UASB)的接种污泥,可以加快反应器的成功启动.在进水氨氮和亚硝酸氮浓度不超过250 mg/L的条件下,厌氧氨氧化反应器稳定运行时NH3-N和NO-2-N的去除率分别可达到80%和90%左右.     

以海绵为填料的厌氧氨氧化反应器对污泥脱滤液的处理效果

为了研究以海绵作填料利用半硝化(PN)-厌氧氨氧化(ANAMMOX)联合工艺对实际废水进行脱氮处理的可行性,在一上流式厌氧固定床反应器中,利用熊本东部的某污水处理厂的污泥脱滤液进行了试验研究.运行结果表明,联合工艺运行时,控制亚硝化反应器温度为(30±1)℃、pH为7.5、溶解氧为1 mg/L时,亚硝化的活性比较稳定,出水NO_2~--N/NH_3-N为1左右.对于ANAMMOX反应阶段,在较高的总氮负荷3.6 kgN/(m~3·d)下,TN、NH_3-N 和NO_2~--N的去除率分别达到70%、72% 和91%,反应器处理效果较好.此外ANAMMOX 反应器在(17±2)℃时NO-2-N去除率低于(25±1)℃时6%;但当环境温度升高时,ANAMMOX菌的活性可以迅速地从低温操作条件下恢复(2～3 d).     

氨氮与亚硝酸盐比对推流式ANAMMOX反应器影响研究

进水基质中NH3-N与NO2--N比例是影响推流式ANAMMOX反应器性能的重要参数。该比例与NH3-N、NO2--N、TN的去除率以及NH3-N与NO2--N的反应比例等参数呈良好的相关性。在同一进水TN负荷条件下,存在一个最佳的进水比例,使TN去除率达到最大。NH3-N和NO2--N的反应比例随着进水基质比例的变化而变化。在反应器中发生的ANAMMOX反应可能有多种含氮的产物形式(不仅是N2一种)。进水基质比例的变化可能会导致ANAMMOX反应复杂化,多种反应途径同时并存。     

SBBR反应器处理粪便污水厌氧出水脱氮效能研究

针对粪便污水厌氧出水高氨低碳(BOD/TN=1)的特点,采用序批式生物膜反应器(SBBR)处理该废水,考察了负荷、NH3-N等对其处理效能的影响;并探讨了低碳源及低温条件下提高反应器脱氮效能的措施.试验结果表明:当水温≥20℃,挂膜密度为30%,有机负荷为0.8 kg CODCr/(m3·d),NH3-N负荷为0.17 kg NH3-N/(m3·d)时,在SBBR反应器中实现了高效的同步硝化反硝化脱氮,使进水CODCr为2 600 mg/L,BODs为500～600 mg/L,NH3-N为500～600 mg/L的污水,出水NH3-N为7.2 mg/L,TN为99 mg/L,NH3-N去除率＞98%,TN去除率＞80%.当反应器中NH3-N≥200 mg/L时,将对自养微生物产生明显的抑制作用.在SBBR反应器进水中接入8%的粪便污水,解决了脱氮过程碳源不足的问题.在低温条件下,通过将反应器的挂膜密度提高至45%,可使TN去除率由84.3%提高至93.4%.     

厌氧氨氧化工艺及其污泥颗粒化的试验研究

厌氧氨氧化工艺是目前最经济简捷的一种新型生物脱氮工艺.本文以两种普通污泥分别接种两个UASB反应器,实现了厌氧氨氧化工艺的启动和稳定运行,培养获得了厌氧氨氧化颗粒污泥,并研究了各种因素对工艺运行的影响规律,结果表明:(1)以厌氧颗粒污泥与好氧活性污泥的混合物以及河底沉积物分别接种启动运行两个小试UASB反应器,以含氨氮和亚硝酸盐氮的无机配水为进水,分别经过115 d和210 d的运行,两个反应器均成功实现了厌氧氨氧化过程,氨氮去除率分别达50%和70%,氨氮去除负荷达0.35和0.29 kgNH3-N/(m3·d),相应的亚硝酸盐氮去除率分别为55%和67%;(2)在两个反应器随后146 d和306 d的稳定运行期间,工艺性能逐步上升,氨氮去除率分别达86%和95%,氨氮去除负荷达0.71和1.20 kgNH3-N/(m3·d),相应的亚硝酸盐氮去除率分别为83%和92%,所产气体中氮气含量高于96%;厌氧氨氧化工艺对进水负荷的突然变化有一定抵抗能力,但温度和溶解氧对工艺性能影响较大;(3)在两个反应器中均获得了厌氧氨氧化颗粒污泥,粒径约为0.6～1 mm,VSS/SS为0.6～0.8,颜色多呈棕黄色,也有少量小粒径颗粒呈红色,在扫描电镜下观察,发现颗粒中的优势菌为不规则球菌,与文献报道的厌氧氨氧化细菌类似;(4)在对颗粒污泥内部微观结构观察和研究的基础上,提出了三种厌氧氨氧化颗粒污泥的形成机理:蜕变附着生物膜机理、无机晶核附着生物膜机理和自凝聚机理;(5)对厌氧氨氧化工艺的主要影响因素进行了系统的研究,发现其最适温度在30～35℃之间,最适pH约为8.2,溶解氧对工艺的抑制作用很强,其浓度应控制在0.01 mg/L以下,由河底污泥培养获得的厌氧氨氧化污泥在上述最适条件下,最高氨氧化速率可达0.184 mgNH3-N/(mgVSS·d);(6)进水中一定浓度的有机物会对厌氧氨氧化工艺产生较大影响,有机物的引入会导致反硝化反应,产生基质竞争性抑制,进水中有机物的长期存在会导致污泥中异养细菌的生长,对厌氧氨氧化工艺产生不利影响.     

好氧硝化污泥启动厌氧氨氧化试验研究

以好氧硝化污泥为培养污泥,采用经稀释的猪场废水启动厌氧氨氧化反应器,经过125 d的培养,根据ASBR反应器出水水样监测结果显示:ASBR反应器稳定运行后NH4+-N、NO2--N的去除率分别达到91.7%、92.0%,说明采用ASBR反应器,接种好氧硝化污泥可成功启动厌氧氨氧化反应器,验证了利用厌氧氨氧化工艺处理类似养殖废水的高氨氮废水的可能性.     

垃圾渗滤液对厌氧氨氧化混培菌活性的影响研究

采用厌氧复合床,经自养型反硝化过程转化,成功启动了厌氧氨氧化反应器,共耗时165d。反应器启动成功后,容积负荷达到了0.17kg总氮/(m3.d),NO2--N与NH+4-N去除率分别为100%和93%。在此基础上,研究了垃圾渗滤液的亚硝化出水对厌氧氨氧化混培菌活性的影响。研究结果表明:在低质量浓度基质(NH+4-N～60mg/L,NO2--N～60mg/L)条件下,垃圾渗滤液亚硝化出水对厌氧氨氧化反应产生了微弱的影响,氨氮的平均抑制率为10.73%,亚氮的平均抑制率为11.71%。     

垃圾渗滤液中有机污染物对厌氧氨氧化的影响研究

采用好氧活性污泥和厌氧颗粒污泥混合接种启动UBF厌氧氨氧化反应器,共耗时165d。反应器启动成功后,容积负荷达到了0.17kg总氮/(m3·d),NO2--N与NH4+-N去除率分别为100%和93%。在此基础上进行垃圾渗滤液有机物浓度梯度实验,研究其在不同有机物浓度下对厌氧氨氧化反应的影响作用。实验结果表明:NH4+-N和NO2--N的去除率随有机物浓度的增加依次降低。当TOC浓度小于100mg/L时,厌氧氨氧化运行稳定,NH4+-N和NO2--N的去除率分别达80%和95%以上;当TOC浓度大于200mg/L时,厌氧氨氧化反应减弱,体系中出现了明显的异氧反硝化反应;当TOC浓度大于500mg/L时,厌氧氨氧化反应几乎完全停止。由于该垃圾渗滤液有机污染物多为难降解的大分子,具有毒性、易降解,有机物的含量较少,因此认为其对厌氧氨氧化的毒性抑制远比竞争性抑制大。     

半固定生物膜载体耦合改良SBR工艺深度脱氮效能及机理研究

传统SBR反应器TN去除效果较差,研究采用半固定生物膜载体模块、污泥回流系统和快速进出水系统优化传统SBR工艺,并开展中试试验探讨工艺深度脱氮的效果和机理。结果表明半固定生物膜载体耦合改良SBR工艺在低进水负荷情况下对COD、NH₃-N、TN和TP的去除率分别为87.19%、98.24%、63.42%和87.06%,高进水负荷情况下去除率分别为94.34%、98.47%、73.47%和73.73%。通过16S rRNA基因序列和PICRUSt2技术分析,悬浮污泥和生物膜载体的微生物群落存在显著差异。在低进水负荷情况下,悬浮污泥主要负责反硝化,生物膜载体主要负责氨氧化,TN主要通过硝化-反硝化去除。在高进水负荷情况下,悬浮污泥中硝酸盐还原酶的作用逐渐减弱,生物膜载体中厌氧氨氧化和氮的同化作用成为主导,TN主要通过同化作用去除。     

曝气生物滤地在污水回用中去除氨氮的试验研究

采用曝气生物滤地(BAF)工艺处理某污水处理厂模拟二级出水,研究了水力负荷及滤料层高度对NH_3-N去除效果的影响.试验结果表明,当进水NH_3-N≤25 mg/L时,平均NH_3-N去除率达到93.12%,出水NH_3-N可降至3 mg/L以下.当水力负荷为1.44 m~3/(m~2·h),HRT为1.8 h时,氨氮的去除效果最好,去除率达到95.32%,出水NH_3-N在1.5 mg/L以下.BAF对NH_3-N的去除作用主要发生在滤料的中上层.     

ANAMMOX and partial denitritation in anaerobic nitrogen removal from piggery waste.

The anaerobic ammonium removal from a piggery waste with high strength (56 g COD/L and 5 g T-N/L) was investigated using a lab-scale upflow anaerobic sludge bed reactor at a mesophilic condition. Based on the nitrogen and carbon balance in the process, the contribution of autotrophic and heterotrophic organisms was also evaluated in terms of the influent NO2-N/NH4-N ratio (1:0.8 and 1:1.2 for Phase 1 and Phase 2, respectively). The result of this research demonstrates that the anaerobic ammonium removal from the piggery waste, using the UASB reactor, can be performed successfully. Furthermore, it appears that by using granular sludge as the seed biomass, the ANAMMOX reaction can start more quickly. Average nitrogen conversion was 0.59 kg T-N/m3 reactor-day (0.06 kg T-N/kg VSS/day) and 0.66 kg T-N/m3 reactor-day (0.08 kg T-N/kg VSS/day) for Phase 1 and Phase 2. The NO2-N/NH4-N removal ratio by the ANAMMOX was 1.48 and 1.79 for Phase 1 and Phase 2. The higher nitrite contents (about 50%) in the substrate resulted in higher nitrite nitrogen removal by the partial denitritation, as well as the ANAMMOX reaction, implying higher potential of partial denitritation. However, the result reveals that the ANAMMOX reaction was influenced less by the degree of partial denitritation, and the ANAMMOX bacteria did not compete with denitritation bacteria. The colour of the biomass at the bottom of the reactor changed from dark gray to dark red, which was accompanied by an increase in cytochrome content. At the end of the experiment, red-coloured granular sludge with diameter of 1-2 mm at the lower part of the reactor was also observed.     

Simulation of denitrification in groundwater from Chaohu Lake Catchment,China

The eutrophication of Chaohu Lake in China is mainly attributed to nitrate inflow from non-point sources in the lake catchment. In this study,biological nitrate reduction from groundwater in the Chaohu Lake Catchment was investigated under laboratory conditions in a continuous upflow reactor. Sodium acetate served as the carbon source and electron donor. Results showed that a carbon-to-nitrogen(C/N) molar ratio of 3:1 and hydraulic retention time(HRT) of 8 d could achieve the most rapid nitrate nitrogen(NO_3~--N) depletion(from 100 mg/L to 1 mg/L within120 h). This rate was confirmed when field groundwater was tested in the reactor, in which a NO_3~--N removal rate of 97.71% was achieved(from60.35 mg/L to 1.38 mg/L within 120 h). Different levels of the initial NO_3~--N concentration(30, 50, 70, and 100 mg/L) showed observable influence on the denitrification rates, with an overall average NO_3~--N removal efficiency of 98.25% at 120 h. Nitrite nitrogen(NO_2~--N)accumulated in the initial 12 h, and then kept decreasing, until it reached 0.0254 mg/L at 120 h. Compared with the initial value, there was a slight accumulation of 0.04 mg/L for the ammonia nitrogen(NH4-N) concentration in the effluent, which is, however, less than the limit value.These results can provide a reference for evaluating performance of denitrification in situ.     

厌氧附着膜膨胀床反应器处理乳品废水的研究

研究厌氧附着膜膨胀床反应器中温处理乳品废水的运行工况。讨论在不同水力停留时间、容积负荷、pH值条件下对COD去除率的影响,并对进出水总氮及氨氮的变化情况进行研究。试验表明:厌氧附着膜膨胀床反应器处理乳品废水,在水力停留时间为8h、中温35℃条件下,COD去处率达到80%以上,对总氮的去除约为8%,出水有机氮的氨化率达70%以上,ρ(BOD)/ρ(COD)由进水的0 5提高到0 8以上。     

Combined partial nitritation/Anammox system for treatment of digester supernatant.

One-year (2004) comprehensive investigations in a semi-industrial pilot plant (5 m3) were carried out with the aim of assessing the influence of operational parameters on the partial nitritation/Anammox system performance. In the system designed as a moving-bed biofilm reactor, the influent nitrogen load to the Anammox reactor was progressively increased and a stable Anammox bacterial culture was obtained. Interaction between subsequent aerobic and anaerobic conditions in the partial nitritation and Anammox reactors, respectively, granted conditions to remove nitrogen through the nitrite route. It implies that the oxygen supply can be limited to a high extent. A control strategy for the partial nitritation step relied on concomitant adjustment of the air supply with a variable influent nitrogen load, which can be monitored by both pH and conductivity measurements. In the Anammox reactor, an influent nitrite-to-ammonium ratio plays a vital role in obtaining efficient nitrogen removal. During the 1-year experimental period, the Anammox reactor was operated steadily and average nitrogen removal efficiency was 84% with 97% as the maximum value.     

Effect of the pH influent conditions in fixed-film reactors for anaerobic thermophilic treatment of wine-distillery wastewater.

In anaerobic treatments, the pH conditions affect the efficacy and operation of the process. The main purpose of this research is to compare the effect of the pH influent on the performance of a high rate technology at laboratory scale, upflow anaerobic fixed-film reactor, treating distillery wastewater (wine vinasses) in thermophilic conditions. The results obtained shown that the pH influent influences the performance of the biodegradation process: the depurative efficiency is higher for the operation with alkaline influent. The operation with acid influent allows us to operate at organic loading rates (OLR) around 5.6 kgCOD/m3/d (hydraulic retention time: 1.5 days), maintaining total Chemical Oxygen Demand removals (CODr) of 77.2%; the operation with alkaline influent allows total CODr of 76.8% working at OLR around 10.5 kgCOD/m3/d. The greatest efficiency of substrate removal was 87.5% for OLR 3.2 kgCOD/m3/d and hydraulic retention time of 4.0 days operating with alkaline influent. Therefore, the operation with alkaline influent implicates senior levels of purifying efficiency for similar organic load rate.     

A /O泳动床反应器脱氮性能研究

基于A/O工艺与泳动床工艺技术的联合,开发出A/O泳动床生物膜反应器.A/O泳动床系统表现出高效去除COD_(Cr)、NH_3-N和TN以及较好的抗负荷冲击能力.在HRT=12.5 h,回流比为300%,进水COD_(Cr)、NH_3-N平均浓度分别为343.4 mg/L、94.1 mg/L时,COD_(Cr)和NH3-N平均去除率分别为84.6%, 86.8%;COD_(Cr)的容积负荷与去除负荷现良好的线性关系,R~2=0.970 4;系统在较低的C/N下,TN平均去除率为70.8%.