【作者】 丁爽；

【导师】 郑平；

【作者基本信息】 浙江大学 ， 环境工程， 2014， 博士

【摘要】 厌氧氨氧化(anaerobic ammonia oxidation, Anammox)工艺是高效、经济、节能的新型生物脱氮工艺,具良好的应用前景和很高商业价值。但该工艺赖以进行的厌氧氨氧化菌存在倍增时间长、细胞产率低且易受外界环境干扰等弱点,工程实践中易受接种物、基质性毒物以及外源性毒物的影响。有鉴于此,本论文针对厌氧氨氧化工艺应用中常遇的问题,开展了厌氧氨氧化关键技术及其机理的研究,主要结论如下：1)研究了厌氧氨氧化工艺的启动特性与污泥特性,提供了可行的厌氧氨氧化接种物的解决方法和简便的污泥比活性监测方法。①试验证明,厌氧产甲烷污泥、新鲜厌氧氨氧化污泥和储藏厌氧氨氧化污泥作为接种物均可成功启动厌氧氨氧化反应器。三种接种物启动厌氧氨氧化反应器呈现不同的过程特征：以厌氧产甲烷污泥为接种物的启动过程包含菌体水解期(15d)、活性迟滞期(54d)和活性提高期(40d)三个阶段；以新鲜厌氧氨氧化污泥和储藏厌氧氨氧化污泥为接种物的启动过程只有活性迟滞期(分别为2d和12d)和活性提高期(分别为15d和57d)两个阶段。三种接种物所启动的厌氧氨氧化反应器呈现不同的运行性能,其优劣次序为：R2(接种物为新鲜厌氧氨氧化污泥)>R3(接种物为储藏厌氧氨氧化污泥)>R1(接种物为厌氧产甲烷污泥)。三种接种物中以新鲜厌氧氨氧化污泥最佳,储藏厌氧氨氧化污泥次之,厌氧产甲烷污泥最差。②研究发现,三种供试接种物启动厌氧氨氧化反应器呈现相似的污泥性能变化过程：污泥物理指标色度值a*、粒径和沉降速度增大；污泥化学指标胞外多聚物和血红素含量升高；污泥生物指标脱氢酶活性和比厌氧氨氧化活性升高。污泥色度值a*,血红素含量、脱氢酶活性和比厌氧氨氧化活性之间存在定量关系。③研究表明,在厌氧氨氧化污泥匮乏时,将厌氧产甲烷污泥用作接种物是一种可行的解决方法；将获得的厌氧氨氧化污泥潜浴于反应器出水中,是储藏厌氧氨氧化接种物的有效方法；将储存的厌氧氨氧化污泥用作接种物是缩短启动时间的有效方法。④研究表明,以色度值a*、血红素含量和脱氢酶活性作为监测指标,可简化厌氧氨氧化启动过程的监测技术,其中以物理指标色度值a*最为简便。2)研究了基质性毒物对厌氧氨氧化反应性能和污泥性能的影响,揭示了基质性毒物对厌氧氨氧化的抑制特性。①试验表明,分批培养条件下,基质氨和亚硝酸对厌氧氨氧化菌的半抑制浓度及其95%置信区间分别为1670.0(1516.7-1820.0)mg·L-1和585.6(241.1～912.1)mg-L-1;两者相对毒性大小为：亚硝酸>氨；氨和亚硝酸的联合作用类型为独立作用,二者各自对厌氧氨氧化菌产生毒害。②试验表明,连续培养条件下,随着基质氨浓度的上升,三组厌氧氨氧化反应器(A1-A3)的容积氮去除速率和基质去除率均较为稳定,联氨积累少,基质氨对厌氧氨氧化反应性能影响不大。随着基质亚硝酸浓度的上升,三组厌氧氨氧化反应器(B1-B3)的性能下降,容积氮去除速率和基质去除率均不断下降,联氨大量积累,基质亚硝酸对厌氧氨氧化反应性能影响较大。③试验表明,连续培养条件下,随着基质氨浓度的上升,污泥色度值a*、血红素含量、脱氢酶活性、胞外多聚物含量、粒径和沉降速度均没有显著变化,基质氨对厌氧氨氧化污泥性能影响不大。随着基质亚硝酸浓度的上升,污泥色度值a*、血红素含量、脱氢酶活性、胞外多聚物含量、粒径和沉降速度均出现不同程度的下降,基质亚硝酸对厌氧氨氧化污泥性能影响较大。④研究揭示,基质亚硝酸的抑制机理为过量亚硝酸抑制厌氧氨氧化关键酶(联氨脱氢酶活)活性,一方面造成代谢受阻；另一方面中间产物联氨积累而毒害细胞,由此形成双重抑制效应。3)研究了外源性毒物(抗生素)对厌氧氨氧化的反应性能和污泥性能的影响,揭示了外源性毒物对厌氧氨氧化的抑制特性。①试验表明,分批培养条件下,青霉素G钠、硫酸多粘菌素B、氯霉素和硫酸卡那霉素对厌氧氨氧化菌的半抑制浓度及其95%置信区间分别为2215.8(1972.2-2611.1) mg·L-1、39.1(35.7-42.4) mg·L-1、441.2(431.8-445.5) mg·L-1和1188.6(1022.7-1318.1)mg·L-1。相对毒性大小为：硫酸多粘菌素B>氯霉素>硫酸卡那霉素>青霉素G钠。②试验表明,分批培养条件下,抗生素之间的复合毒性效应以及基质和抗生素之间的复合毒性效应多为相加作用,少部分为协同或独立作用。二元抗生素混合物中,青霉素G钠+硫酸卡那霉素、氯霉素+硫酸卡那霉素为独立作用；青霉素G钠+氯霉素、硫酸多粘菌素B+硫酸卡那霉素为协同作用；其余两组为相加作用。三元抗生素混合物中,硫酸多粘菌素B+氯霉素+硫酸卡那霉素为协同作用,其余三组均为相加作用。基质+抗生素的处理组均为相加作用。③试验表明,连续培养条件下,四种抗生素均对反应器性能产生不利影响,造成反应器容积氮去除速率和基质去除率下降,引起中间产物联氨积累。与分批培养试验结果相比,四种抗生素在较低浓度下即影响厌氧氨氧化反应器性能,四种抗生素的毒性强弱与分批培养试验一致。四种抗生素均对反应器的污泥活性产生不利影响,造成污泥色度值a+、血红素含量和脱氢酶活性下降。④研究揭示,在外源性毒物胁迫时,厌氧氨氧化菌会启动自我保护机制,通过超量合成胞外多聚物(尤其是胞外蛋白),屏蔽不良环境因素的影响。4)建立了厌氧氨氧化示范工程,探究了生产性厌氧氨氧化装置处理含氨制药废水的启动模式。①短程硝化-厌氧氨氧化工艺可成功实现制药废水生物脱氮。制药废水进水氨氮浓度平均为(430.40±55.43)mmg·L-1,出水氨氮浓度平均为(24.26±11.37)mg·L-1,氨氮去除率平均为(81.75+9.10)%,厌氧氨氧化系统的容积氮负荷平均为(4.31±1.07) kgN·m-3·d1,容积氮去除速率平均为(3.66±0.96) kgN·m-3·d-1。②“两步法”运行模式适用于短程硝化系统的工程调试。以制药废水启动短程硝化系统的时间约为74d,短程硝化系统的亚硝氮积累率平均为(52.11±9.13)%,实现半量硝化；最大容积氮负荷为0.26kgN·m-3·d1,最大容积氮去除速率为0.15kgN·m-3·d-1,可为后续厌氧氨氧化工艺提供基质。③“造血”结合“输血”的菌种流加式运行模式适用于厌氧氨氧化系统的工程调试。以制药废水启动厌氧氨氧化系统的时间约为145d,厌氧氨氧化系统的最大容积氮负荷为6.96kgN·m-3·d-1，最大容积氮去除速率为6.35kgN·m-3·d-1,容积效能处于生产性装置的领先水平。更多还原

【Abstract】 Anaerobic ammonia oxidation (Anammox) process is a new type of biotechnology for nitrogen removal with high efficiency and low cost, which has a very good application prospect and high commercial value. But Anammox bacteria are chemoautotroph with long double time and low yield rate. Besides, they are sensitive to changes of environmental conditions. The large-scale application of Anammox process is often limited by the seeding Anammox sludge, substrates and exogenous toxicants (i.e. antibiotics). Therefore, some key technologies and their mechanisms are investigated to solve these problems. The main results are as follows:1) The start-up characteristics and sludge characteristics were revealed, and a method to solve the shortage of seeding sludge and a method to monitor the specific Anammox activity were established.It was proved that anaerobic methanogenic sludge (AMS), fresh Anammox sludge (FAS) and stored Anammox sludge (SAS) could be used to start up Anammox-EGSB bioreactors successfully (the reactors were named Rl, R2and R3, respectively). But the start-up progresses showed different characteristics. The start-up course of R1could be divided into three phases including autolysis phase (15d), lag phase (54d) and activity elevation phase (40d). The start-up courses of R2and R3only included lag phase (2d and12d, respectively) and activity elevation phase (15d and57d, respectively). The performance of R3was better than that of R1, but worse than that of R2. The physical parameters color value a*, particle diameters and settling velocities were raised. The chemical parameters extracellular polymeric substances (EPS) and heme contents are elevated. Besides, the biological parameters dehydrogenase activity (DHA) and specific Anammox activity (SAA) were also promoted. The color value a*, heme contents, DHA and SAA were closely related to each other. Under the condition without supply of Anammox sludge, AMS could be used as the seeding sludge for Anammox process. Bathing the Anammox sludge in the effluent of bioreactors was a convenient way to keep the activity of Anammox sludge. Seeding Anammox reactor with SAS was effective way to shorten the start-up time. Color value a*, heme content or DHA could serve as the parameters to monitor the SAA of Anammox sludge, whose measurements were more convenient than the batch test. Among them, color value a*was the simplest and most environmental friendly.2) The influence of two substrates on Anammox reaction and sludge characteristics was studied and the inhibition mechanism of endogenous toxicants was explored.The batch tests showed that the half inhibition concentrations (IC50) and their95%confidence interval of ammonia and nitrite were1670(1516.7～1820.0) mgN·L-1and585.6(241.1～912.1) mgN·L-1. Nitrite was more toxic than ammonia. The joint action of ammonia and nitrite was independent. The continuous cultivation tests showed that the performances of reactor Al, A2and A3were steady, which meant ammonia did not inhibit Anammox reaction under the setting ammonia concentrations. However, the performances of reactors B1, B2and B3were sharply down, which meant nitrite inhibited Anammox reaction under the setting nitrite concentrations. The physical, chemical and biological parameters of the sludge in A1, A2and A3did not have significant changes while the situation was totally different in B1, B2and B3. All the parameters declined sharply. All the changes of sludge characteristics were in accordance with the reactors’performances. The inhibition mechanism of nitrite is as follows:the excessive nitrite inhibited the activity of key enzyme hydrazine dehydrogenase (HDH), which led to the disturbance on substrate catabolism. On the other hand, the accumulated intermediate hydrazine (N2H4) could poison the Anammox cell.3) The influence of exogenous toxicants (four antibiotics) on Anammox performance and sludge characteristics was studied and the inhibition mechanisms of exogenous toxicants were explored.The batch tests showed that the half inhibition concentrations (IC50) and their95%confidence interval of penicillin G-Na, polymyxin B sulfate, chloramphenicol and kanamycin sulfate were2215.8(1972.2-2611.1)mg·L-1、39.1(35.7-42.4) mg·L-1441.2(431.8-445.5) mg·L-1and1188.6(1022.7-1318.1) mg·L-1. The antibiotics toxicities were as follows:polymyxin B sulfate> chloramphenicol> kanamycin sulfate> penicillin G-Na. The joint actions of antibiotics or the joint actions of substrates and antibiotics mostly belonged to additive effect. Only small part of treatment groups belonged to synergistic effect or independent effect. The continuous cultivation tests showed that the performances of reactors with different antibiotics dosage declined with the increase of antibiotics’concentrations. All the changes of sludge characteristics were in accordance with the reactors’performances. The inhibition concentrations got from continuous cultivation tests were much lower than those from batch tests. Under the exogenous toxicant stress, Anammox bacteria might produce much more EPS, especially extracellular protein to form the barrier to prevent the cell from the toxicants. This was similar to the self-protection mechanism of other bacteria.4)In order to solve the nitrogen pollution from strong-ammonium pharmaceutical wastewater, a full-scale short-cut nitrification process combined with Anammox process was investigated. The results showed that the short-cut nitrification process and Anammox process could successfully remove nitrogen from pharmaceutical wastewater. In the combined system, influent ammonia and effluent ammonia were (430.40±55.43) mg-L-1and (24.26±11.37) mgL-1, respectively. Ammonia removal efficiency was (81.75±9.10)%. Volumetric nitrogen loading rate and volumetric nitrogen removal rate of Anammox process were (4.31±1.07) kgN·m-3·d-1and (3.66±0.96) kgN·m-3·d-1, respectively. Two-step mode using synthetic wastewater and real wastewater was suitable for operations of the short-cut nitrification system which provided substrates for Anammox system. The start-up took about74d. Nitrite accumulation efficiency was (52.11±9.13)%. Maximum volumetric nitrogen loading rate and volumetric nitrogen removal rate were0.26kgN·m-3·d-1and0.15kgN·m-3·d-1, respectively. The combination of Anammox sludge growth with sequential biocatalyst addition was suitable for the operation of Anammox process. The start-up process took about145d. Maximum volumetric nitrogen loading rate and volumetric nitrogen removal rate were6.96kgN·m-3·d-1and6.35kgN·m-3·d-1, which were in the leading level in full-scale reactors.更多还原