厌氧时间对间歇进水-间歇曝气的好氧颗粒污泥系统影响

为启动生活污水AGS工艺,实验以间歇进水-间歇曝气方式运行,降低硝氮浓度,减轻对PAO的抑制,利用除磷中产生的磷酸盐沉淀和正电微粒促进颗粒化实现.接种污水厂污泥于SBR反应器R1、R2、R3和R4中,在总厌氧时间为30、60、90和120 min时,研究厌氧时间对生活污水AGS系统的影响.实验表明,R1、R2、R3和R4历时56、48、39和35 d启动成功;运行105 d,平均粒径达750、764、791和650μm.运行期间,R1和R2在43 d和47 d除磷恶化,延长厌氧时间至90 min后恢复;R3处理效果良好; R4在63～77 d颗粒解体,处理效果下降,DPAO富集程度降低.运行后期,R1、R2、R3和R4出水水质均满足《城镇污水处理厂污染物排放标准》一级A标准.结果表明,长厌氧时间运行能实现快速颗粒化,但长期运行时颗粒易解体.较长的厌氧时间能减轻硝氮对PAO释磷的抑制,有助于富集DPAO,能获得良好的脱氮除磷效果.     

FeCl3改性污泥生物炭对水中吡虫啉的吸附性能研究

以脱水污泥为原料,制备污泥生物炭（SBC）和FeCl₃改性污泥生物炭（Fe-SBC）处理低浓度吡虫啉（IMI）废水（浓度为10 mg·L^-1）,考察SBC和Fe-SBC对IMI的吸附性能及影响因素,并探究其吸附机理.采用SEM、XRD、FTIR、BET及元素分析等探得污泥生物炭FeCl₃改性成功.Fe-SBC对IMI的最大吸附量为4.915 mg·g^-1,是SBC的1.97倍,表现出更好的IMI吸附性能.pH和离子强度的变化对Fe-SBC的吸附性能影响较小,最大波动幅度分别为4.4%和7.8%.两种生物炭对IMI的吸附均符合准二级动力学模型,Freundlich模型可以更好地描述其等温吸附曲线.热力学研究表明,SBC吸附IMI是非自发吸附,而Fe-SBC是自发吸附.Fe-SBC对IMI的吸附机理包括静电作用力、氢键作用力及π-π键相互作用力.多次热解再生后的Fe-SBC对IMI的去除率仍可达93.088%.     

氯化剂对超细颗粒物与重金属共生成特性的影响

以循环流化床反应器为实验平台,研究了焚烧温度为850℃下添加剂（NH₄Cl和KCl）对超细颗粒物与重金属共生成特性的影响.结果表明：NH₄Cl和KCl的存在均会降低超细颗粒物的数量浓度,但KCl的效果更佳,发挥的是阶梯式或者协同式作用.此外,添加比例为3%时对超细颗粒物数量浓度的降低最为明显.重金属Cr,Mn,Ni主要通过夹带方式形成超细颗粒物;而重金属Pb,Cu,Zn则主要通过蒸发、冷凝和吸附方式累积在超细颗粒物中.无机氯在焚烧过程中可以作为颗粒之间良好的粘合剂,促进超细颗粒物之间的成长和团聚,同时促进其表面形态的生长.此外,K的存在会促进细模态颗粒物之间的凝聚成长,使得细模态颗粒物的峰值增大,而NH₄⁺的存在会降低粗模态颗粒物的峰值.本研究可为污泥等废物热处理过程中重金属与超细颗粒物的协同控制提供借鉴.     

不同预处理方法促进剩余污泥发酵制氢研究进展

综述了剩余污泥发酵制氢的底物预处理方法,主要包括物理法（热水解法、微波法、超声波法、冻融法）;化学法（酸碱预处理、臭氧氧化法）;生物法（生物强化技术、生物酶法）,分析比较了不同预处理方法的剩余污泥发酵制氢体系的氢气含量及产率,污泥处理后溶解性化学需氧量、挥发性脂肪酸含量的变化和工程应用的优缺点,并指出目前研究存在的一些不足和对未来应用前景的展望,以期为剩余污泥发酵制氢预处理方法的研究与应用提供依据.     

EGSB-CANON工艺启动及动力学特性

采用EGSB（Expanded Granular Sludge Bed）反应器,在启动全程自养脱氮（CANON）工艺中通过改变曝气方式以及优化曝气/非曝气逐步实现CANON工艺的稳定运行.通过研究不同曝气/非曝气条件下CANON工艺的脱氮性能的变化,探究系统内不同污泥粒径中功能菌的活性,揭示EGSB反应器不同的运行条件以及系统内不同粒径的微生物聚集体在CANON工艺启动过程中的影响机制与菌群结构特性.结果表明,当恒定曝气量为0.5L/min,曝气/非曝气为2：1（60min：30min）时,实现了AerAOB（Aerobic Ammonia-Oxidizing Bacteria）与AnAOB（Anaerobic Ammonium-Oxidation Bacteria）协同脱氮的目的,并成功将NOB（Nitrite-Oxidizing Bacteria）的活性由3.41mgN/（h·gVSS）抑制到0.75mgN/（h·gVSS）.在对AnAOB的双底物（NO₂^--N和NH₄⁺-N）抑制动力学结果进行Haldane拟合时,得到NH₄⁺-N和NO₂^--N的半饱和常数（k_s）、抑制动力学常数（k_h）分别为106.8,331.9mg/L,272.4,66.61mg/L,相关性系数（R²）分别为0.98133和0.99142.在CANON污泥颗粒化形成过程中,污泥粒径在0.154~0.335mm范围内主要以AerAOB为主,污泥粒径在1mm以上主要以AnAOB为主.不同粒径下微生物聚集体的协同作用以及稳定的群落结构实现了CANON工艺的稳定运行.     

鼠李糖脂-热对污泥厌氧发酵中脱水性能的影响

为了探究鼠李糖脂以及低温热水解预处理污泥厌氧发酵过程对污泥脱水性能的改变,利用毛细吸水时间（CST）表征脱水性能指标,有机物溶出、粒径分布以及三维荧光光谱分析阐明脱水性能变化机制.研究发现在厌氧发酵之前,预处理后污泥脱水性能均会降低;厌氧发酵之后原污泥脱水性能降低,经过热水解的污泥脱水性能改善;粒径分布变化表明粒径减小是预处理污泥脱水性能变差的部分原因,发酵之后粒径增大对于污泥脱水性能改善不明显.溶解性有机物（SCOD）、溶解性碳水化合物（SC）以及溶解性蛋白质（SP）的溶出情况发现粒径的减小是由于预处理手段对污泥的有效破解.三维荧光平行因子分析（PARAFAC）表明,污泥预处理且厌氧发酵前后溶解性有机质（DOM）均包含类腐殖酸C1（386nm/462nm）和C3（342nm/438nm）、酪氨酸类蛋白C2（278nm/306nm）以及色氨酸类蛋白C4（290nm/358nm）.其中,类腐殖酸的增多是热水解污泥脱水性能变差的主要原因,厌氧发酵之后酪氨酸蛋白的积累是原污泥脱水性能变差的原因,类腐殖酸的分解是热水解污泥发酵后改善的原因.     

长期饥饿后SPNA微颗粒污泥系统性能恢复

为了确定长期饥饿后连续流一段式部分亚硝化-厌氧氨氧化（SPNA）工艺的性能恢复情况,采用连续流反应器,考察了在室温下（11~23℃）经历161d饥饿期的SPNA系统性能恢复策略的可行性及脱氮性能和菌群结构变化.通过控制DO浓度及进水氨氮负荷,逐渐实现亚硝酸盐氧化菌（NOB）的抑制和淘汰、氨氧化菌（AOB）和厌氧氨氧化菌（AnAOB）的活性恢复和富集.在68d内系统总氮去除率恢复至72.13%,氨氮去除率恢复至94.75%.微颗粒污泥（³200μm）的占比从42.04%升至60.98%.微生物群落结构分析发现,停止运行161d后系统Candidatus Kuenenia的相对丰度升至25.53%,表现出较强的抵抗饥饿条件的能力,系统恢复后其相对丰度逐渐降低,接近反应器饥饿前水平.AOB的高底物利用能力是系统恢复的前提,AnAOB活性的提高是系统恢复的关键.系统性能的成功恢复表明室温下161d饥饿期对系统造成的影响是可逆的,长期室温下储存SPNA污泥是可行的.     

Enhanced nitrogen removal upon the addition of volatile fatty acids from activated sludge by combining calcium peroxide and low-thermal pretreatments

This study investigated a combined low-thermal and CaO₂ pretreatment to enhance the volatile fatty acid (VFA) production from waste activated sludge (WAS). The fermentative product was added to a sequencing batch reactor (SBR) as an external carbon source to enhance nitrogen removal. The results showed that the combined pretreatment improved WAS solubilization, releasing more biodegradable substrates, such as proteins and polysaccharides, from TB-EPS to LB-EPS and S-EPS. The maximum VFA production of 3529 ± 188 mg COD/L was obtained in the combined pretreatment (0.2 g CaO₂/g VS + 70 °C for 60 min), which was 2.1 and 1.4-fold of that obtained from the sole low-thermal pretreatment and the control test, respectively. Consequently, when the fermentative liquid was added as an external denitrification carbon source, the effluent total nitrogen decreased to Class A of the discharge standard for pollutants in rural wastewater treatment plants in most areas of China.     

Flow analysis of major and trace elements in residues from large-scale sewage sludge incineration

Increase of sewage sludge (SS) has led to the construction of more incineration plants, exacerbating to the production of SS incineration residues. However, few studies have considered the mass balance of elements in large-scale SS incineration plants, affecting the residues treatment and utilization. In this study, flow analysis was conducted for major and trace elements in the SS, the fly ash (sewage sludge ash, SSA) and bottom ash from two large-scale SS incineration plants. The elemental characteristics were compared with those of coal fly ash (CFA), and air pollution control residues from municipal solid waste incineration (MSWIA), as well as related criteria. The results showed that the most abundant major element in SSA was Si, ranging from 120 to 240 g/kg, followed by Al (76–348 g/kg), Ca (26–113 g/kg), Fe (35–80 g/kg), and P (26–104 g/kg), and the trace elements were mainly Zn, Ba, Cu, and Mn. Not all the major elements were derived from SS. Most trace elements in the SS incineration residues accounted for 82.4%–127% of those from SS, indicating that SS was the main source of trace elements. The partitioning of heavy metals in the SS incineration residues showed that electrostatic precipitator ash or cyclone ash with high production rates were the major pollutant sinks. The differences in some major and trace elements could be indicators to differentiate SSA from CFA and MSWIA. Compared with related land criteria, the pollutants in SSA should not be ignored during disposal and utilization.     

Isolation and characterization of a strain with high microbial attachment in aerobic granular sludge

Aerobic granule is a special microbial aggregate associated with biofilm structure. The formation of aerobic granular sludge is primarily depending on its bacterial community and relevant microbiological properties. In this experiment, a strain with high microbial attachment was isolated from aerobic granular sludge, and the detailed characteristics were examined. Its high attachment ability could reach 2.34 (OD_600nm), while other low attachment values were only around 0.06-0.32, which indicated a big variation among the different bacteria. The strain exhibited a very special morphology with many fibric fingers under SEM observation. A distinctive behaviour was to form a spherical particle by themselves, which would be very beneficial for the formation and development of granular sludge. The EPS measurement showed that its PN content was higher than low attachment bacteria, and 3D-EEM confirmed that there were some different components. Based on the 16S rRNA analysis, it was identified to mostly belong to Stenotrophomonas. Its augmentation to particle sludge cultivation demonstrated that the strain could significantly promote the formation of aerobic granule. Conclusively, it was strongly suggested that it might be used as a good and potential model strain or chassis organism for the aerobic granular sludge formation and development.