强化生物除磷系统中聚磷菌与聚糖菌的种群分析及代谢机制研究进展

强化生物除磷(EBPR)工艺是目前国内外广泛应用的废水除磷技术之一。微生物的研究对于提高EBPR系统的除磷稳定性有着非常重要的意义。综述了EBPR系统中聚磷菌和聚糖菌的种群分析及其代谢机制、聚磷菌与聚糖菌之间竞争的影响因素等方面的研究进展。分析了目前相关研究中存在的不足,并展望了今后相关的研究发展方向。     

温度对SBR强化生物除磷工艺除磷性能的影响

以厌氧/好氧交替运行的序批式反应器(SBR)为对象,利用荧光原位杂交技术(FISH),研究了温度(20、25和30℃)对强化生物除磷(EBPR)的影响。结果表明,温度为20℃时,系统的磷去除率高于98%,厌氧释磷速率和好氧吸磷速率分别为55.70 mg P·(gVSS·h)~(-1)和45.16 mg P·(gVSS·h)~(-1),聚磷菌(PAOs)占总细菌(EUB)的比例达到90%,而聚糖菌(GAO)的比例只有1%;温度升高到25℃后,除磷效果不断降低,释磷速率和吸磷速率逐渐下降,PAOs的比例下降,而聚糖菌(GAOs)的比例不断增加;温度为30℃时,出水水质恶化,磷去除率仅为67%,释磷速率和吸磷速率分别为33.66 mg P·(gVSS·h)~(-1)和17.55 mg P·(gVSS·h)~(-1),GAOs的比例高达87%,而PAOs的比例仅为5%,在与PAOs的竞争中,GAOs处于优势,导致除磷效果降低。     

COD对强化生物除磷系统的影响及OUR的变化规律

以实际生活污水为研究对象,在SBR系统中采用厌氧/好氧运行方式,考察强化生物除磷(EBPR)系统中好氧阶段COD浓度对聚磷菌除磷性能的影响以及不同好氧阶段COD浓度下的OUR变化规律.实验分4个阶段进行,分别为不投加外碳源、厌氧结束时投加不同体积的乙酸钠作为外碳源,使COD分别提高50、100和300mg/L.4种工况...     

剩余污泥水解酸化液磷去除的影响因素研究

城市污水厂剩余污泥水解酸化后可产生高浓度挥发性有机酸(VFAs),其中的乙酸和丙酸是增强生物除磷(EBPR)工艺的有利基质.但水解酸化液中含有大量的磷,如不进行处理就作为碳源回用到污水处理工艺中,势必增加除磷负荷.利用鸟粪石沉淀法可以去除污水中的磷.对城市污水厂剩余污泥水解酸化液形成鸟粪石的影响因素进行了试验研究.结果表明,在最佳工艺条件下,正磷和总磷的去除率分别可达92.5%和83.8%.     

长期缺氧吸磷驯化下强化生物除磷系统污泥除磷方式的转化

采用交替厌氧/缺氧/好氧运行的序批式活性污泥反应器(SBR),通过梯度投加电子受体NO_3~-,考察长期缺氧吸磷驯化下强化生物除磷(EBPR)系统的性能及除磷方式的转化。结果表明,当进水COD为300～450mg/L、PO_4~(3-)(以P计,下同)和氨氮分别为8、14mg/L时,驯化期间TN去除率均保持在75%以上,长期缺氧吸磷驯化对COD和氨氮的去除没有影响。硝态氮投加量为5mg/L时,EBPR系统因电子受体投加不足除磷性能迅速恶化,增加硝态氮投加量至10mg/L,经过近30d的恢复,缺氧吸磷率最高可达97.67%,进一步提高硝态氮投加量至15mg/L,系统内硝态氮的积累导致缺氧吸磷率下降。污泥吸磷小试结果表明,经缺氧吸磷驯化后,即使除磷性能欠佳的低浓度电子受体系统污泥也具有良好的反硝化吸磷能力,可见经NO_3~-长期驯化的缺氧吸磷系统有利于筛选以NO_3~-为电子受体的反硝化聚磷菌。     

富磷污泥厌氧消化磷释放与回收的研究进展

生物强化除磷(EBPR)工艺会产生大量的富磷污泥。富磷污泥中的聚磷菌(PAOs)在厌氧消化过程中吸收外界碳源并释放大量正磷,高浓度的磷会对厌氧消化系统中厌氧微生物的代谢产生影响,使得消化过程更加复杂。富磷污泥厌氧消化过程会产生磷、氮、有机物和金属离子等物质,其中磷的回收利用可以减少磷矿资源的开采,从而实现磷资源的可持续循环利用。因此,研究富磷污泥厌氧消化过程中磷的变化规律,既为厌氧消化系统的稳定运行提供理论依据,又为磷的资源化回收利用提供参考。对富磷污泥厌氧消化释磷的相关研究成果以及磷回收进行分析和总结,并提出了相应的研究方向。     

洛克沙胂对污水生物除磷的影响研究

以合成废水为研究对象,在厌氧/好氧交替序批式反应器(SBR)中探究了不同浓度洛克沙胂对污水生物除磷的影响,并对影响机制进行分析。实验结果表明:低浓度洛克沙胂对生物除磷效果影响不明显,而高浓度洛克沙胂将严重抑制生物除磷效果,当洛克沙胂的质量浓度为90mg/L时,生物除磷效率仅为62.6%,是空白对照组的63.5%。高浓度洛克沙胂将抑制聚磷菌(PAO)中胞内聚合物聚羟基脂肪酸酯(PHA)的合成,导致好氧阶段PHA分解产能较低,影响PAO对磷酸盐的超量吸收。此外,高浓度洛克沙胂会促进糖原质的降解,提高聚糖菌(GAO)的相对丰度而降低PAO的相对丰度,并且对PAO中的关键酶活性产生不利影响。     

一株耐低温反硝化聚磷菌的筛选及其特性研究

通过吸磷试验、硝酸盐还原产气试验及异染颗粒和PHB颗粒染色辅助检验,并采用模拟自然降温方式,从稳定运行的厌氧/缺氧SBR反应器中分离筛选出在低温下(8℃)仍具有高效能的一株反硝化聚磷菌H16.经鉴定,H16属于假单胞菌属(Pseudomonas).在低温下,探讨了pH值、微量元素对菌株的生长及除磷效能的影响,结果表明,菌株H16生长最适pH为7～8,除磷反应的最佳pH值为7;微量元素的缺乏对H16的生长和除磷效能都有一定的不良影响.同时测定了H16的生长曲线.     

几种常见离子对粉煤灰合成沸石除磷效果影响研究

研究了几种常见无机离子(SO2-4、HCO-3、NO-3、SiO2-3、Ca2 、Mg2 )对3种阳离子饱和的粉煤灰合成沸石(Ca沸石、Al沸石和Fe沸石)除磷效果的影响.结果表明,与纯水比较,NO-3和SO2-4的存在能提高沸石的磷去除率;HCO-3对沸石除磷起抑制作用;高浓度的SiO2-3显著提高溶液pH,从而促进Ca沸石的除磷,但抑制Al沸石和Fe沸石的除磷作用;Ca2 的存在能够显著提高沸石的磷去除率;Mg2 能促进Al沸石和Fe沸石除磷,但对Ca沸石除磷有一定抑制作用.     

一体式PN/A耦合EBPR工艺高效低耗处理实际低C/N主流城市污水

针对低C/N城市污水脱氮除磷因碳源不足存在能耗、药耗高以及脱氮除磷效率低等问题,开发一体式短程硝化/厌氧氨氧化(PN/A)耦合强化生物除磷工艺(EBPR),以降低碳源消耗和能耗、提高脱氮除磷效率,从而实现高效低耗减污降碳。通过构建悬浮污泥和生物膜共存的混合系统,采用厌氧-好氧运行模式以及间歇曝气,考察短程硝化/厌氧氨氧化与强化生物除磷过程的耦合效果。结果表明,反应器能长期稳定运行,出水总无机氮(TIN)质量浓度稳定低于4 mg·L^-1,溶解态磷(DP)质量浓度约0.2 mg·L^-1,TIN平均去除率大于90%,DP的平均去除率大于85%,平均脱氮负荷为53 mg·(g·d)^-1,强化间歇曝气能够在系统内实现NOB抑制,亚硝氮积累率可达60%以上,甚至100%。控制悬浮污泥好氧污泥龄为3.5 d,NOB由悬浮污泥向填料转移。由于生物膜传质受限,系统的亚硝氮积累率并未受到影响。该系统内厌氧氨氧化活性提高了5倍,厌氧氨氧化菌以Candidatus Brocadia为主,相对丰度为1.1%,较主流条件下提高了2.75倍。本研究结...     

Modeling the spill in the Songhua River after the explosion in the petrochemical plant in Jilin

An explosion in a petrochemical plant in Jilin in the northeast of China on 13 November 2005 was responsible for the discharge of large quantities of benzene and nitrobenzene into Songhua River. This endangered the water supply of Harbin city and influenced the daily life for millions of people. The dispersion-advection equation was solved analytically and numerically and used to simulate the concentration of benzene and nitrobenzene in the Songhua River after the accident. Both solutions gave practically identical results. The main elimination process for both compounds was volatilization. The model results are quite close to the results obtained by measurements at monitoring stations. Arrival time of the pollutant wave, peak concentrations and end of the pollutant wave at Harbin and along the river were predicted successfully. The peak concentrations of nitrobenzene at Harbin were more than 30 times above the permissible limits for drinking water.     

焦化废水中细菌质粒的研究

细菌质粒中常带有一些可编码降解特殊有毒物质酶的基因,为了研究质粒对有毒物质CN^-的降解的意义,主要调查了焦化废水中好氧异养菌的质粒分布特点。从山西省焦化企业公司生化站、太原煤气公司焦化厂生化站中筛选出53株细菌,利用琼脂糖凝胶电泳法,采用GDS-8000型凝胶电泳分析仪进行拍照,同时测定各菌株降氰、降酚能力,CN^-采用异烟酸-毗唑啉酮法,酚采用4-氨基安替比林法测定。结果表明,质粒的存在与降氰力有一定的关系,但对降酚力的影响差异不显著。同时,通过对其中11^*号菌株进行了质粒转化和消除实验,证明质粒稳定,不可用十二烷基磺酸钠(SDS)消除掉,用E．cbli DHI作受体菌,用11^#菌株作供体菌。作转化实验,但由于种种原因,没有筛洗到转化子。     

Managing the relationship with the environment

This article describes the results of a survey carried out by the author's company on behalf of Rank Xerox. The objective was to assess attitudes towards environmental issues in both the public and private sector. Although there were some differences over priorities, both sectors agreed that development of environmental policies was essential to their future.     

水处理中含铁废料综合利用的研究进展

回顾了２０余年来我国在水处理中综合利用含铁废料的研究进展，分别评述了副产品硫酸亚铁制备絮凝剂ＰＦＳ的各种方法，废铁屑运用于内电解法水处理和其他含铁泥渣，废酸在水处理中的研究和应用现状，指出含铁废料综合利用中有待于进一步研究的若干问题。     

How the loss of forest fauna undermines the achievement of the SDGs

The human-driven loss of biodiversity has numerous ecological, social, and economic impacts at the local and global levels, threatening important ecological functions and jeopardizing human well-being. In this perspective, we present an overview of how tropical defaunation—defined as the disappearance of fauna as a result of anthropogenic drivers such as hunting and habitat alteration in tropical forest ecosystems—is interlinked with four selected Sustainable Development Goals (SDGs). We discuss tropical defaunation related to nutrition and zero hunger (SDG 2), good health and well-being (SDG 3), climate action (SDG 13), and life on land (SDG 15). We propose a range of options on how to study defaunation in future research and how to address the ongoing tropical defaunation crisis, including but not limited to recent insights from policy, conservation management, and development practice.     

底泥修复中温度对微生物活性和污染物释放的影响

通过分析底泥中微生物的酶活性以及污染物的释放规律,探讨了温度对河道底泥生物修复的影响.结果表明,底泥中微生物的脱氢酶、脲酶和磷酸酶的活性随着温度的升高而显著增大,但温度对纤维素酶的活性影响较小.4 ℃和10 ℃时底泥中污染物的释放量和微生物的酶活性均较低,水质较稳定;20～37 ℃时底泥中污染物的释放量明显增加,微生物的新陈代谢能力有较大提高,水体的自净能力较强.在各种因素的综合作用下,20～30 ℃是进行底泥生物修复的适宜环境温度.此外,当pH为9.0以及添加葡萄糖时,底泥中微生物均表现出较高的脱氢酶活性.     

Isolation of the stable fraction (the core) of the humic acid

Humic acid consists of a recalcitrant (unhydrolysed fraction) (the core) and labile (hydrolysable fraction) fraction. Core-humic acid (core-HA) isolation was performed by treating source material with apolar and polar solvents (organic solvents+acid hydrolysis) before alkaline extraction. Leonardite, soil Ah horizont and dry blood were chosen for this study because of their different origin and degree of humification. Chemical analysis (elemental analysis, total acidity, E(4):E(6)), spectroscopic analysis (DRIFT and (1)H NMR), and complete mass balance were used to investigate the effect of purifying humic acids. The results obtained showed that purification produced a slight modification of Leonardite humic acids as was expected for these highly humified organic matrices. On the other hand, about 500 g kg(-1) of soil humic acids were lost by purification. The fractions lost mainly consisted of carbohydrates. Dry blood showed the presence of humic acids that contrasted with its origin, thus indicating the limitations of the common analytical methods used for HA extraction. Nevertheless, in practice, purification caused the complete disappearance (914 g kg(-1) of HA was lost) of these HAs. The results obtained in this work suggest that the HA fraction isolated (named core-HA) effectively represents the HA structure proposed by the existing literature, since the purification proposed was able to eliminate the adsorbed organic molecules (interference materials) coating the HA structure.