990 resultados para aerobic wastwater treatment


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花椒(Zanthoxylum bungeanum)是川西干旱河谷地区重要的经济作物,化感作用是花椒连作障碍的重要原因之一。花椒凋落物分解是影响花椒林地土壤肥力及花椒产量的重要因素,因此系统研究花椒化感作用是否对花椒凋落物的分解产生影响可以为解决花椒连作障碍导致的产量下降等问题提供科学的理论依据。本文通过室内模拟实验研究了花椒凋落物的四个分解动态以及分解后凋落物浸提液对花椒林地土壤性质的影响;通过野外盆栽实验研究了花椒凋落物浸提液对花椒幼苗的生长、花椒凋落物的质量及土壤性质的影响。最终从生理生化角度揭示了花椒的化感作用对凋落物分解的影响机理,为深入解决花椒连作障碍问题、对花椒凋落物采取有效的人工措施提供了科学的理论依据。主要的研究结果如下: 1. 室内分解实验证明,花椒凋落物在分解的60 d 内分解速率呈现由大到小的变化趋势,并且凋落物分解呈现明显的毒性动态。凋落物在分解的10 d、30 d 时,分解速率较大,30 d 以后分解速率显著降低。凋落物分解的10 d 左右酚酸释放量最大,此时凋落物的毒性最大,凋落物分解到10 d 以后,酚酸释放量逐渐减少,凋落物的毒性也逐渐减小。 2. 四个分解动态的花椒凋落物浸提液对土壤化学性质产生了显著的影响。花椒凋落物在分解的60 d 内,其浸提液使土壤pH值均显著的增加。分解0 d 的凋落物浸提液显著的降低了土壤铵态氮的含量,抑制了纤维素分解菌的生长;分解60 d 的凋落物浸提液显著的降低了土壤酚酸含量,增加了土壤有效磷的含量;分解30 d 和60 d 的凋落物浸提液均显著的促进了好气性纤维素分解菌的生长。这说明花椒凋落物在分解过程中呈现出明显的毒性动态:凋落物分解的初期毒性作用较大,随着分解的继续进行特别是在分解的30 d 以后,其毒性作用慢慢降低。 3. 花椒凋落物浸提液对花椒幼苗表现出明显的化感作用。不同浓度的浸提液对花椒幼苗地上及地下生物量、叶面积均产生了显著的抑制作用,并且随着浸提液浓度的升高抑制作用加强。凋落物浸提液对叶片厚度的影响较小,只有Y1对叶片厚度的生长抑制作用显著。 4. 花椒的化感作用改变了凋落物的质量,并对凋落物分解产生了显著的影响。对花椒幼苗用不同浓度的凋落物浸提液进行处理,Y1使凋落物有机碳含量、木质素含量、C/N、木质素/氮显著降低,纤维素含量显著升高;Y3使凋落物有机碳含量、木质素含量、C/N、木质素/氮显著升高。花椒凋落物质量的改变显著的影响了凋落物的分解,凋落物的分解速率大小依次为:Y1(10.15 a-1)> Y2(8.71 a-1)> CK(6.41 a-1)> Y3(5.08 a-1)。 5. 花椒的化感作用改变了土壤性质,并对凋落物分解产生了显著的影响。对花椒幼苗用不同浓度的凋落物浸提液处理的同时,也改变了土壤性质。不同浓度的凋落物浸提液显著的升高了土壤pH值、有机碳含量。各种浓度的凋落物浸提液对土壤多酚氧化酶的活性均起到了显著的促进作用。凋落物浸提液Y1对土壤纤维素分解酶的活性、细菌和真菌的生长也具有显著的促进作用。土壤性质的改变显著的影响了凋落物的分解,凋落物的分解速率大小依次为:Y1(10.30 a-1)>Y2(9.60 a-1)>CK(6.41 a-1)>Y3(6.29 a-1)。 6. 不论是凋落物质量发生改变还是土壤性质发生改变,在凋落物分解的整个过程中,C元素始终处于单调净释放的状态,并且C释放量与分解速率成显著的正相关,即凋落物分解越快,凋落物C释放量越大。凋落物分解过程中,均出现了酚酸大量释放的情况,并与凋落物分解速率成显著正相关。凋落物分解后的木质素含量、木质素/氮均增加,并且随着浸提液浓度的升高,凋落物木质素含量、木质素/氮升高。 Zanthoxylum bungeanum is an important economic crop in dry valley of the Minjiang river (Sichuan, Southwest China), but allelopathy is one of the important reasons for its continuous cropping. Zanthoxylum bungeanum litter decomposition affects Zanthoxylum bungeanum soil fertility and its output. So systemically investigate if allelopathy affects litter decomposition could provide the scientific methods to solve the problem of output fall caused by the continuous cropping. In this paper, the releasing dynamics of phenolic acid during Zanthoxylum bungeanum litter decomposition (0, 10, 30 and 60 days) and the effects of its aqueous extract on soil chemical properties were investigated via the laboratory study. Effects of Zanthoxylum bungeanum litter aqueous extract on the growth of young Zanthoxylum bungeanum seedlings, litter qualities and the soil qualities were investigated via the field study. Finally, we open out the action manner of Zanthoxylum bungeanum allelopathic effect on the litter decomposition, and provide the theoretical basis to solve the Zanthoxylum bungeanum continuous cropping. The main results showed that: 1. The laboratory litter decomposition experiment showed a trend of decomposition rate from large to small and an occurrence of phytotoxicity with clear dynamic patterns during Zanthoxylum bungeanum litter decomposition. The litter decomposition rate was larger at the tenth and 30th day during 60-day litter decomposition and gradually decreased after 30 days of litter decompostion. The releasing quantity of the litter phenolic acid was the highest at the tenth day, and here, the litter toxicity was the biggest. The releasing quantity of the litter phenolic acid gradually decreased after 10 days of litter decomposition, so the phytotoxicity of litter was gradually decreased with the litter decomposition. 2. The Zanthoxylum bungeanum litter aqueous extract after four decomposition stages had significantly effect on the soil chemical qualities. The pH value in soil was significantly increased in litter aqueous extract of four decomposition stages. The NH+4-N concentration was significantly decreased in soil amended with litter aqueous extract of 10-day decomposition which inhibited the growth of Aerobic cellulose-decomposer. The growth of soil Aerobic cellulose-decomposer was promoted by the litter aqueous extract of 30-day decomposition. Available phosphorus concentration was significantly increased and phenolic acid content was significantly decreased in soil amended with litter aqueous extract of 60-day decomposition which promoted the growth of Aerobic cellulose-decomposer. The study results showed an occurrence of phytotoxicity with clear dynamic patterns during Zanthoxylum bungeanum litter decomposition. The phytotoxicity of litter was the largest at the initial stage, but the phytotoxicity gradually decreased with the litter decomposition, especially after 30 days of decomposition. 3. The field study indicated that the Zanthoxylum bungeanum litter aqueous extract had significant allelopathic effects on the growth of young seedlings.Different concentration aqueous extract had signinficant inhibiting effects on biomass and leaf area of young seedlings. The inhibiting effect on the biomass strengthened with the litter aqueous extract concentration augment. Litter aqueous extracts had less effect on the leaf thickness, and only Y1 had significant inhibiting effect on the leaf thickness. 4. The Zanthoxylum bungeanum allelopathy had significant effect on the litter qualities and the litter decomposition. Treating the young Zanthoxylum bungeanum seedlings with different concentration of litter aqueous extracts, the leaf litter organic C, lignin, C/N and lignin/N all decreased and the cellulose content increased under Y1 treatment. The leaf litter organic C, lignin, C/N and lignin/N all increased under Y3 treatment. So the litter decomposition was significant affectded by the litter qualities, and the litter decomposition rate was Y1(10.15 a-1)> Y2(8.71 a-1) > CK(6.41 a-1) > Y3(5.08 a-1). 5. The Zanthoxylum bungeanum allelopathy had significant effect on the soil qualities and the litter decomposition. Treating the young Zanthoxylum bungeanum seedlings with different concentration of litter aqueous extracts, also changed the soil qualities. Different concentration of litter aqueous extracts had significant effects on the soil pH and organic C content. Every concentration of litter aqueous extracts accelerated the soil Polyphenol Oxidase activity and Y1 accelerated the soil Cellulase activity, the number of soil bacteria and fungi. So the litter decomposition was significant affected by the soil qualities, and the litter decomposition rate was Y1(10.30 a-1) > Y2 (9.60 a-1) >CK(6.41 a-1)>Y3(6.29 a-1)。 6. Whether the litter or soil qualities changed, the litter C element at the state of release at all times during the litter decomposition, and the release quantity increased with the decomposition rate augment. Litter released plentiful total penolics content during decomposition, and the release quantity had the positive correlation with the litter decomposition rate. The litter lignin content and the lignin/N all increased with the litter aqueous extracts concentration augment after litter decomposition.

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一体化反应器由于投资少、占地小、管理运行方便等优点而备受青睐。但现有的一体化反应器大都适用于处理中低浓度废水,耐受负荷普遍偏低。本课题研制出新型高效的厌氧好氧一体化生物反应器,旨在通过反应器结构优化、高效微生物载体研制、配合高效微生物菌剂技术处理中高浓度有机废水,实现高效和低耗,降低设备造价,提高反应器运行稳定性。 首先开展了菌剂对废水的适配试验。采用15种不同的微生物菌剂,以葡萄糖配水、中药提取废水、啤酒废水、氨氮配水为基质,分别测定了微生物菌剂的耗氧速率和厌氧比产甲烷速率,以其为指标比较了各菌剂对废水的适配性。根据结果选择活性高的14#、8#、10#菌剂,在试验室进行了菌剂对废水的连续处理试验,取得良好的处理效果,为菌剂在厌氧好氧一体化生物反应器的小试、中试中的应用奠定了基础。 经小试研究后,又对厌氧好氧一体化生物反应器进行了处理发酵废水的中试研究。试验结果表明,反应器启动快,系统有机负荷2.72 kgCODm-3d-1时整个反应器去除率保持在84.5%~93.19%,在30多天内一次启动成功。冲击负荷试验中,系统总有机负荷最高可达到8.88 kgCODm-3d-1,系统去除率稳定在88.10%~96.88%,说明反应器处理效率高,抗冲击能力强。稳定运行期间,COD去除率可达90%以上,各项指标都能达到国家排放标准。 此外,对反应器配套系统高效菌剂、高分子复合颗粒载体进行了研究。结果显示,菌剂与反应器适配良好,各功能区形成了丰富、高活性的微生物,厌氧区颗粒污泥TS高达83.9 gL-1,VS/TS为56.9%~57.4%,比产甲烷活性为280~350 mLCH4 gvss-1d-1;好氧区固定化微生物TS高达1.921 gL-1,VS/TS为94.02~94.30%。对载体性能的研究表明,此高分子复合颗粒载体密度适中,易于流化,不易流失;粗糙多空,易于挂膜;且无生物毒害作用,稳定安全,是一种优良的生物载体。反应器各功能区对废水的降解过程分析,说明了反应器、菌剂、载体适配良好,在其协同作用下,实现了污染物的高效降解。 The integrated reactors were popular because of their characteristics such as little investment, small occupation of land, convenient of manage and running etc. But the present integrated reactors were mostly applied for treating wastewater of low concentration, the load tolerance was generally on the low side. A new type integrated anaerobic-aerobic bio-reactor was developed, which was conducted to treating organic wastewater of middle or high concentration by optimization of reactor structure, development of efficient microbe carrier and adaptation of high active microbial blends, to achieve high efficiency and low consume, reduce equipment cost, enhance running stabilization of reactor. The adaptability test of microbial blends on different wastewater was carried on firstly. Oxygen consumption rate and anaerobic specific activity of methane producing of 15 different microbial blends were measured separately taking glucose artificial wastewater, Chinese herb extracting wastewater, brewery wastewater and ammonia nitrogen artificial wastewater as substrate, by which the adaptabilities of different microbial blends to wastewater were compared. According to the results high active microbial blends 14#, 8# and 10# were selected and used in the continuous treatment of wastewater in the laboratory and had obtained good effect, which had laid a foundation for application microbial blends to small scale test and pilot test of integrated anaerobic-aerobic bio-reactor. After the small scale test, the pilot test of the integrated anaerobic-aerobic bio-reactor treating fermentation wastewater was carried on. The test results showed fast initiation of the reactor. When system organic load reached 2.72 kgCODm-3d-1the COD removal rate of the reactor was stable between 84.5%~93.19% and it initiated successfully in more than 30 days at a time. In the load shock test the maximum organic load of system could reach to 8.88 kgCODm-3d-1 and the COD removal rate could be stable between 88.10%~96.88% which indicated that the reactor was efficient for treating wastewater and had strong resistance to shock load. At stable running period the COD removal rate of the reactor was over 90% and each index of wastewater could reach to the national discharge standards. In addition, the high active microbial blends and the macromolecule compound granule carrier, the matching system of the reactor was studied. It showed that the microbial blends adapted well to the reactor and abundant and high active microbes were formed in each functional field. The TS of granule sludge in anaerobic field was as high as 83.9 gL-1, the VS/TS was 56.9%~57.4%, the specific activity of methane producing was 280~350 mLCH4 gvss-1d-1. And the TS of immobilized biological granule was as high as 1.921 gL-1, the VS/TS was 94.02%~94.30%. Study on the carrier showed that the self-made macromolecular compound granule carrier was moderate of density, easy of fluidization, unease of running off, rough and porous, easy of films fixation, no bio-toxic, stable and safe, was a kind of superior carrier. Analysis of degradation process in each functional field confirmed the reactor, microbial blends and carriers were in good adaptation and wastewater was decontaminated by their cooperation.

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恶臭假单胞菌;异养硝化-好氧反硝化;自养硝化;生活污水脱氮;Pseudomonas putida;heterotrophic nitrification-aerobic denitrification;autotrophic nitrification;nitrogen removal for domestic wastewater treatment

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本文介绍了从厌氧间歇膨胀光合反应器内的活性污泥中分离并鉴定的泥生绿菌(Chlorobium limicola Nadson)S1,它属严格厌氧光能自养型细菌,在有硫化物和少量碳酸氢盐存在下,有广泛利用有机物的能力,它的最适生长温度为28-30℃,最适生长PH为6.5-7.0,且含有氢化酶。因此,它能与甲烷发酵菌共存而共同作用,达到废水净化之目的。通过光照(2#反应器)和黑暗(1#反应器)对比实验,表明了在光照条件下即有泥生绿菌S1存在下,反应系统能更好地降低CODcr、BOD5 和提高CH4 含量,在四个负荷段的运行中,2#反应器在后三个负荷段的甲烷含量能稳定在91.6%而1#反应器为87%,2#反应器的二氧化碳含量为4.5%而1#反应器为8.8%,于28.35g/l.d的负荷下,2#反应器CODcr去除率达83.4%,BOD去除率达74.53%,分别较1#反应器高10.8%,6.4%。COD去除率提高了14%,BOD去除率提高了9.3%。本试验的试验条件为:白天自然光照,晚上电源光照,光照强度为1000-2500lux,通过连续动态运转,并以恒定的流速将废液注入反应器中,进水PH控制在6.5-7.2,反应器厌氧,恒温室温度控制在30±1℃。为使整个试验中同一水质条件下进行,进水采用化学合成培养基。This paper reports a Chlorobium Liwicola S1's isolation and identification. It is a strictly anaerobic and photosynthetic autotrophic bacterium. Along with sulfidedepondent CO2 assiwilaton,a few simple organic compounds can be photoassimilated. Acetate is most effectively used. Its best conditons of growth are 28-30℃,PH 6.5-7.0, and it contains hydrogenase. So it can live with methanefermentative bacteria in order to treat wastewater. At the same time, the treatment of wastwater using Chlorobium Limicola S1 with methane-fermontative bacteria under dark anaerobic and light anaerobic conditions is studied. In contrast with 1# reactor-darken, 2# reactor-illuminated can lossen wastewater's CODcr, BOD5 and on hance CH4 content better. In the test, 2# reactor's CH4 content is stable at 91.6%, but 1# reactor's is 87%. The CO2 content of 2# reactor is 4.5%, but 1# reactor's is 8.8%. When the load of teatment is 28.35g/l.d, the COD removal effficiency is 83.4% and the BOD removal efficiency is 74.53% in 2# reactor. They are separately 10.8%, 6.4% higher than 1# reactor's.

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造纸行业是造成我国水环境有机污染物的重要污染源之一,其水污染的特点是小厂多、草浆多、工艺落后、污染扩散面广、造成废 水排放量大,每年排放的废水量约39亿立方米,占全国工业废水排放量的1/6,其中有机污染物(以BOD5计)160万吨左右,约占全 国工业废水中有机污染物总量的1/4。尤以占全国制浆造纸行业90%以上的碱法草浆造纸厂的蒸煮黑液量大面广,除含有机物外,还 含有木质素、残碱、硫化物、氯化物等污染物,属于PH值高、色度深、难于治理的高浓度有机废水,对水体污染特别严重,各地要 求治理呼声很高,急待研究并尽快找出各种有效的治理途径。对于碱法草浆蒸煮,黑液高浓度废水的治理,有各种方法,根据国内 的研究进展和我们已有试验工作表明,最经济有效,具有实用价值,在生产上可获得成功是厌氧处理法。近10多年来,国外关于高 效厌氧处理技术研究进展迅速,并出现了多种多样的工艺设备,如高效厌氧生物反应器,并在实用化方面取得了很大成绩,建立了 生产性装置,达到了高负荷运行,效果良好。本试验是根据我们已有研究基础,针对我国国情,对小型制浆造纸厂水污染防治除了 开发碱回收及各种综合利用技术外,要特别加强废水(废液)实用技术研究的指导思想,本试验采用改进型的上流式厌氧污泥床反应 器,设计了两种试验方案,通过试验结果如下。1. 试验方案I—碱法草浆黑液酸化和厌氧发酵I号UASB反应器动态模型试验结果表 明:(1). 采用中温35℃±1℃高效厌氧反应器USAB内装有填料(陶粒)和三相分离器,具有保持高浓度生物量和防止污泥流失的特点 ,污泥浓度Vs 可达30%以上,因而具有高效、节能、产能、滞留期短的优点,当进水CODcr在7500-10000mg/l,HRT由7天缩短到3天 ,有机容积负荷在1.22gCODcr/l·d-3.43gCODcr/l·d时,CODcr平均去除率可达55%-45.5%,最高CODcr去除率可达60.2-63.5%, BOD5去除率可达75.9-83.2%,沼气容积产气率可达0.29-0.67l/l·d,每克CODcr转化为沼气产率达0.39-0.48l/gCODcr·d,CH4含量 65.8-75.5%。厌氧发酵出水再用化学法进行后处理脱除难降解的木质素,CODcr总去除率达80%以上。(2). 动态试验结果表明:采 用酸化—厌氧发酵处理黑液工艺合理,技术路线可行。2. 试验方案II—黑液用化学法(Hcl)去除木质素进行厌氧发酵,II号UASB反 应器动态模型试验结果表明:(1). 采用中温35℃±1℃高效厌氧反应器UASB(内有软填料),当进水CODcr7000-13000mg/l左右,HRT 由6天缩短到1天,有机负荷由0.98gCODcr/l·d增加到11gCODcr/l·d时,COD平均去除率均可稳定在70-77%,BOD5去除率为87.3- 93.1%,沼气容积产气率0.21-2.6l/l·d,每克CODcr转化为沼气产率为0.39-0.48l/gCODcr·d,高的可达0.53l/gCODcr·d,转化 率较高,CH4含量63-70%。(2). 试验证明碱法草浆黑液物化预处理—厌氧发酵处理的技术路线也是可行的,工艺合理、效果较好。 在有条件的工厂可采用。3.厌氧发酵阶段几大类群微生物计数表明:(1). 当发酵工艺和运行处于相对稳定状态时,微生物群体的 组成也达到相对的稳定,各类微生物之间保持动态平衡关系。当产乙酸菌的数量为107-108个/ml时,产甲烷菌的数量为105-106 个/ml,当产乙酸菌数量为106-107个/ml时,产甲烷菌的数量为103-105个/ml。(2).稳态运行条件下,黑液预处理为甲烷发酵创造 了有利的生态环境,获得了较好的处理效果和较高的COD转化为沼气的产率0.39-0.48l/g·CODcr·d,反应器中形成较为稳定而数 量较下水污泥中高1-2个数量级的厌氧发酵微生物区系组成。这一结果为黑液厌氧发酵提供了微生物理论依据。Paper industry is one of the important pollution source of water environment in our country. Its character of water pollution is many small factories, much grass pulp, disadvantageous technique, large preading area of pullution. Its effluent makes up 1/6 of whole country's industry wastwater. Its organic pollutant accounts 1/4 of whole country's. Alkaline grass paper pulp effluent with pollutants such as ligoin, remaining alkali sulfide, chloride besides organic material, is a kind of high concentrate organic wastewater which has high PH walug, dark colour and is difficult in treatment. There is urgent require to find ways to treat the wastewater. There are different ways to treat alkaline paper grass pulp effluent. According to the research advances and our experiment work, the most economical and useful way is anaerobic degradation which was advanced quick in last ten years. In the control of waste water of small pulp paper mill, the study of wastewater utilization technology should be emphasized, besides alkaline retrieving and different kinds of comprehensive utilization technology. Our experiment used modified UASB(Upflow Anaerobic Sludge Blanket Reactor). Two kinds of plan were disgned. The results are lined below. 1. The first experiment plant-aciding black pulp effluent and methanogenic digestion. The dynamic model experiment results of I-UASB reactor showed: (1)The mesophilic(35℃±1℃)high effect UASB reactor having haydite and threee state seperation in it had the character of keeping high bioimass concentration and preventing losss of sludge. It had advantages of high effect, energe saving, energe prodcing and short HRT(Hydroulic retention time). When the influent COD was 7500-10000mg, HRT was shortened from 7 days to 3days, organic loading rate was 1.22g-3.43COD/l· d, the average COD removal efficiency was 55%-45%. The highest COD efficiency was 60.2-63.5%, BOD removal of 75.9 -83.4% was achieved. Biogass production rate were up to 0.29-0.67l/l·d. Biogass converted efficiency from every gram of COD could reach 0.39-0.48l/gCOD·d. Methane content was 65.0-75.5%. Chemical method was used to deplate lignin in anaerobic digestion effluent. Total COD removal efficiency could be more than 80%. (2)Using aciding annaerobic digestion to treat the black effluent was reseanable in technique and technology. 2. The second experiment plan-anaerobic digestion was used after the chemical method was used to deplate lignin in the black effluent. The result of dynamic experiment of II-UASB reactor showed: (1)High effect mesophilic (35℃±1℃)UASB reactor having soft slaffing in was used. When influent COD was about 7000-13000mg/l, HRT was shortened from 6 days to 1 day and organic loading rate was increased from 0.90 to 11g COD /l·d, average COD removal efficiency remained stable on 70-77%. BOD, removal efficiency was between 87.3-93.1%. Biogass production rate was 0.2-2.6l/l ·d .Biogass converted efficiency from a gram of COD was 0.39-0.481/gCOD·d with the high value of 0.53l/gCOD·d. Methane content was 63-70%. (2)The way that using physical, chemical Pre-treatment-anaerobic digestion to treat alkaline black effluent is feasible and can be used in some factories when the condition exists. 3. Counting of several class of microoganisms in anaerobic digestion stage showed: (1)As the disgestion was in stable motion, the compositon of microorganic colony could get relative stable. Dynamic balance was remaining among different kinds of microorganism such as methanogenic bacteria, Acidogenic bacteria, sulfate reducing bacteria, and heterotrophic bacteria. (2)Under stable motion, the pre-treatment of black effluent produced favourable eco-enviroment for methanegenic digestion. Good treatment effect and high biogass convertent efficiency from COD(0.39-0.48l/g·COD· d)were gotten. Some stable and high quantity(10-100times more than sewage sludge)microorganism colony were formed in the reactor. This result provided theoretical basis for anaerobic digestion of black effluent.

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畜禽废水是农村水环境污染的主要来源之一,其处理的难点在于脱氮。传统生物脱氮法具有能耗高、需大量外加碳源等缺点,开发低成本、高效率的新型生物脱氮技术具有重要意义。 本研究将短程硝化反硝化和厌氧氨氧化两种脱氮新技术结合,让前者为后者创造去除可降解COD、降低总氮负荷、调整pH、调整氨氮和亚硝酸盐氮浓度比例等进水条件,而后者可在无需外加碳源的条件下进一步脱氮,二者结合可成为高氨氮、低C/N废水脱氮的新途径。 试验以低碳氮比猪场废水为研究对象,首先进行了短程硝化反硝化预处理研究,同时启动并运行调控厌氧氨氧化反应器,最后以经过短程硝化反硝化预处理的猪场废水为进水,进行厌氧氨氧化脱氮考察。实验表明:(1)短程硝化反硝化作为厌氧氨氧化的预处理工序是可行的。猪场废水通过短程硝化反硝化,可以达到基本去除可生化COD、部分脱氮、控制出水氨氮和亚硝酸盐氮浓度之比在1︰1左右、pH在7.5~8.0的目的, COD和总氮平均去除率分别为64.3%、49.1%,出水可达到厌氧氨氧化反应的进水要求。(2)采用模拟废水启动厌氧氨氧化反应器,经过5个月左右的运行调控,反应器启动成功并稳定运行,最高总氮去除率为87.1%,总氮容积去除率最高达到0.14kg/m3.d;整个稳定阶段,氨氮、亚硝酸盐氮、硝酸盐氮的变化量之比为1︰1.21︰0.33。(3)经过短程硝化反硝化预处理的猪场废水厌氧氨氧化脱氮效果稳定,氨氮、亚硝酸盐氮、总氮、COD的平均去除率分别为93.0%、99.4%、84.6%、18.1%,处理效果与模拟废水处理系统相比无明显变化。(4)经过短程硝化反硝化预处理后,猪场废水中残留有机物成分在厌氧氨氧化反应过程中无显著变化,主要为酯类和烷烃类物质;残留有机物对厌氧氨氧化效果无明显影响。(5)采用PCR技术进行特殊功能菌种检测,结果表明模拟废水处理系统和猪场废水处理系统的菌群中均含有厌氧氨氧化菌和好氧硝化菌;通过blast比对,厌氧氨氧化菌扩增序列与未培养的Planctomycetales菌和Candidatus Brocadia fulgida菌16S rRNA部分序列相似性分别为95%、90%。(6)MPN法菌种计数结果显示,模拟废水处理系统和猪场废水处理系统的菌群中均含有硝化细菌、亚硝化细菌和少量反硝化菌,实验条件下的微生物系统是一个厌氧氨氧化菌与好氧硝化菌、反硝化菌共存的系统。 Poultry wastewater is one of the main source of water pollution in rural areas,and nitrogen removal is the most difficult part in treating poultry wastewater. There are some disadvantages in traditional nitrogen removal, such as high energy consumption and more additional organic carbon. It is important to develop ecolomical and efficient technologyies. Shortcut nitricfication/denitrification, as a pretreatment process, was combined with Anammox in this research, so that part of total nitrogen and most degradable COD could be removed by the former, and further nitrogen removal could be implemented by the latter. The combination of the two technologies was a new approach to treat wastewater with high ammonium and low C/N. Piggery wastewater with low C/N was treated in lab-scale experiment. Firstly, shortcut nitrification/denitrification was investigated, and Anammox reactor was started up successfully at the same time. Then piggery wastewater after pretreatment was treated by Anammox. The results showed :(1) It was feasible to take nitrification/denitrification as the pretreatment process of Anammox. By using this process, part of total nitrogen and COD were removed, the ratio of ammonium and nitrite reached around 1︰1 and the pH was about 7.8, which were favorable for Anammox. The average removal percentage of COD and total nitrogen were about 64.3% and 49.1%, respectively. (2) Simulated wastewater was used to start up Anammox reactor. The reactor was started up successfully within 5 months and stable performance was achieved. The highest nitrogen removal reached 87.1% and the biggest volumetric total nitrogen removal rate reached 0.14kg/m3.d. The average ratio of ammonium, nitrite and nitrate was 1:1.21:0.33. (3)Taking the effluent of shortcut nitrification/denitrification as the influent, the nitrogen removal efficiency of Anammox was stable, and the the average removal percentage of ammonium, nitrite, total nitrogen and COD were 93.0%, 99.4% , 84.6% and 18.1%, respectively, which had little difference with that by using simulated wastewater..(4) After pretreatment, the residual organic carbon in piggery wastewater showed no obvious change during the Anammox process, and the main organic compounds were saturated hydrocarbon and ester, which had no obvious negative effect on Anammox process.(5) By PCR technology, the existence of Anammox bacteria was confirmed and the aerobic nitrifying bacteria was found to coexist as well. The result of blast showed that the identities of Anammox bacterium to part of 16S rRNA sequence of uncultured Planctomycetales bacterium and Candidatus Brocadia fulgida bacterium were 95% and 90%, respectively.(6)By MPN method, nitrite oxidizer, ammonium oxidizer and denitrification bacteria were detected in both simulated and piggery wastewater treatment system of Anammox, and the microorganism system was composed of Anammox bacteria,aerobic bacteria and denitrification bacteria together.

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自养硝化过程在自然界氮素循环和污水处理系统脱氮过程中起着关键作用。因此,了解有机碳对硝化的影响和硝化菌与异养菌之间的竞争对微生物生态学和污水处理系统设计都很重要。目前对氨氧化到硝酸盐氮过程的研究文献很多,但对亚硝酸盐氧化过程在异养菌的存在下如何受到有机碳影响的研究甚少。本文从生理生化指标、基因组学、蛋白组学三方面考察了在实验室条件下有机碳(乙酸钠)对硝化细菌和异养菌组成的混合菌群的硝化性能、菌群结构及代谢功能的变化的影响。 全文分为两大部分: 第一部分为乙酸钠对游离态硝化混合菌群的硝化性能和菌群结构的短期影响。混合菌株先在自养条件下进行连续培养,两个月后硝化速率达到20 mg N/(L·d);而后离心收集菌体进行批式实验。在批式反应器中,初始亚硝氮均为126mg N/ L,乙酸钠-C 与亚硝酸盐-N 的比分别为0,0.44,0.88,4.41,8.82。结果表明:在低C/N 比(0.44 和0.88)时,亚硝酸盐去除速率比C/N=0 下高,细菌呈现一次生长;而在高C/N 比(4.41 和8.82)时,出现连续的硝化反硝化,亚硝酸盐去除率仍比对照下高,细菌呈现二次生长。不同C/N 比下微生物群落明显不同,优势菌群从自养和寡营养细菌体系(包括亚硝酸盐氧化菌,拟杆菌门,α-变形菌纲,浮霉菌门和绿色非硫细菌下的一些菌株)过渡到异养和反硝化菌体系 (γ-变形菌纲的菌株尤其是反硝化菌Pseudomonas stutzeri 和P. nitroreducens 占主导)。 第二部分为乙酸钠对硝化混合菌群生物膜的硝化性能和菌群结构的长期影响。接种富集的硝化混合菌群于装有组合式填料的三角瓶中,于摇床中自养培养;两个月后填料上形成生物膜的硝化速率达到20 mg N/ (L·d);而后进行长期实验,每12 小时更换混合营养培养基(亚硝氮约200 mg N/ L,C/N 比同上)。结果显示:相较于C/N 比=0 时的亚硝酸盐氧化反应来说,低C/N 比出现了部分的反硝化,而高C/N 比则是几乎完全的反硝化。与对照比,C/N=0.44 时亚硝酸盐氧化速率并未受乙酸钠的影响,反而上升了,但C/N=0.88 时亚硝酸盐氧化速率有所下降。菌群结构分析表明自养对照与混合营养下微生物群落的不同;PCR-DGGE未检测出混合营养下硝化杆菌的存在,而显示异养菌尤其是反硝化菌的大量存 在。荧光定量PCR 结果表明随C/N 比上升,硝化杆菌数量从2.42 × 104 下降到1.34× 103 16S rRNA gene copies/ ng DNA,反硝化菌由0 增加至2.51 × 104 nosZgene copies/ ng DNA。SDS-PAGE 的结果表明不同C/N 比下的蛋白组较为复杂且呈现一定的差异性。 有机碳对亚硝氮氧化及微生物群落的影响很复杂,本文分别讨论了对游离态和生物膜固定态两种状态的混合菌群相应的短期和长期影响研究。研究发现,有机碳并非一定带来硝化的负影响,如果控制在适当的C/N 比范围,有机碳是有利于亚硝氮氧化的。这些发现阐明了有机碳和硝化反硝化的关系,填补了硝化微生物生态学上的空白,对污水处理系统中减少异养菌的影响并提高氮去除率有一定理论指导意义。 Nitrification plays a key role in the biological removal of nitrogen in both nature and wastewater treatment plant (WWTP). So, understanding of the effect of organic carbon on nitrification and the competition between nitrifying bacteria and heterotrophic bacteria is important for both microbial ecology and WWTP design and operation. Despite the fact that the nitrification process of ammonia to nitrate has been extensively investigated, it is not known how the process of nitrite oxidization is affected by organic carbon when heterotrophic bacteria are present. By measuring different physiological and biochemical parameters, as well as using genomic DNA and proteome analysis, we investigated the influence of organic (acetate) on nitrite oxidizing performance, community structure and metabolic function of nitrite-oxidizing and heterotrophic bacteria under laboratory conditions. The dissertation involves two parts: Part one deals with the effect of organic matter on functional performance and bacterial community shift of nitrite-oxidizing and heterotrophic bacteria under suspended state. The bacteria were prepared in a continuous-flow stirred reactor under autotrophic condition; after two months, the nitrification rate of the culture reached about 20 mg N/ (L·d); then the bacteria were harvested for the next batch experiments. The initial concentrations of nitrite were 126 ± 6 mg N/ L in all flasks, and sodium acetate (C) to nitrite (N) ratios were 0, 0.44, 0.88, 4.41, and 8.82, respectively. The results showed that at low C/N ratios (0.44 or 0.88), the nitrite removal rate was higher than that obtained under autotrophic condition and the bacteria had single growth phase, while at high C/N ratios (4.41 or 8.82), continuous aerobic nitrification and denitrification occurred besides higher nitrite removal rates, and the bacteria had double growth phases. The community structure of total bacteria strikingly varied with the different C/N ratios; the dominant populations shifted from autotrophic and oligotrophic bacteria (NOB, and some strains of Bacteroidetes, Alphaproteobacteria, Actinobacteria, and green nonsulfur bacteria) to heterotrophic and denitrifying bacteria (strains of Gammaproteobacteria, especially Pseudomonas stutzeri and P. nitroreducens). Part two describes the influence of acetate on nitrite oxidizing performance, community structure and metabolic function of nitrite-oxidizing and heterotrophic bacteria in biofilms. Bacterial enrichments was transferred into flasks with polypropylene carriers and cultured under agitated and autotrophic condition. After two month, the biofilms grown on the carriers had a nitrification rate of about 20 mg N/ (L·h); then the biofilms were refreshed with mixotrophic medium (nitrite were 200 mg N/ L in all flasks, and C/N ratios was the same as above) every 12 h. the results show: normal nitrite oxidization reactions were performed when C/N = 0, but nitrite oxidization and partial denitrification occurred with low C/N ratios (0.44 or 0.88). At high C/N ratios (4.41 or 8.82), we mainly observed denitrification. In contrast to C/N = 0, the nitrite oxidization rate was unaffected when C/N = 0.44, but decreased with C/N = 0.88. The structure of bacterial communities varied significantly between autotrophic and mixotrophic conditions. Nitrobacter was hard to detect by PCR-DGGE while heterotrophs and especially denitrifiers were in the majority under mixotrophic conditions. Real-time PCR indicated that the Nitrobacter population decreased from 2.42 × 104 to 1.34 × 103 16S rRNA gene copies/ ng DNA, while the quantity of denitrifiers obviously increased from 0 to 2.51×104 nosZ gene copies/ ng DNA with an increasing C/N ratio. SDS-PAGE indicated the complexity of and a certain difference between the proteome of nitrite-oxidizing and heterotrophic bacteria at different C/N ratios. We conclude that the influence of organic matter on nitrite oxidation and the community structure of NOB and heterotrophic bacteria is complex. In this dissertation, we focused on how sodium acetate influenced the system both under suspended state and in biofilms. We observed that acetate did not necessarily have a negative impact on nitrification. Instead, an appropriate amount of acetate benefited both nitrite oxidization and denitrification. These findings provide a greater understanding about the relationship between organics and nitrification; they fill the gaps in the field of microbial ecology of nitrifying bacteria; they also provide insight into how to minimize the negative impact of heterotrophic bacteria and maximize the benefit of nitrogen removal in biological treatment systems.

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活性污泥法是目前世界上普遍应用的污水生物处理工艺,其在运行过程中产生大量的剩余污泥。由于剩余污泥处理费用巨大及污泥最终处置对环境具有潜在危害问题,污泥的处理和处置已经成为水处理领域关注的焦点。本文利用实验室筛选的溶胞菌群,在好氧消化的同时对污泥进行前处理,促进剩余污泥的破解与溶胞,再通过两相厌氧处理对污泥进行进一步消化,以研究投加溶胞菌对剩余污泥消化的影响。 本研究中溶胞菌污泥减量化技术分为两个部分,第一,污泥在溶胞菌作用下的好氧消化与污泥传统好氧消化的对比研究,利用取自成都三瓦窑污水处理厂剩余污泥,向好氧污泥消化反应器中投加溶胞菌,检测各项污泥指标,并通过同传统好氧污泥消化对比,以研究溶胞菌对污泥好氧消化的影响。第二, 经过溶胞菌处理后好氧消化的剩余污泥进行两相厌氧处理研究。通过建立好氧溶胞联合两相厌氧消化系统的来处理剩余污泥,并与相同条件运行的两相厌氧消化系统做对比,检测运行过程中系统中物质成分变化,研究了其处理能力和运行稳定性,探索了两相厌氧消化系统中的发酵类型差别,验证了好氧溶胞对剩余污泥的破解效果。 研究结果表明:污泥在溶胞菌作用下的好氧消化效果和消化效率均优于传统好氧消化。在溶胞菌群存在的情况下,剩余污泥的TSS和VSS去除率达到40%和53%,远高于传统好氧消化的12%和20%。污泥经过溶胞及好氧消化后,TCOD去除率达到54.4%。经过溶胞菌处理后的剩余污泥再进入两相厌氧处理系统,进入厌氧处理系统的剩余污泥的VSS/TSS比值约为0.62。在两相厌氧处理水力停留时间(HRT)为8d时,溶胞处理污泥厌氧消化后VSS去除率达到55.17%,对照组两相厌氧系统的VSS去除率平均值为18.53%。经过溶胞处理的两相厌氧系统的污泥减量了能力远高于对照组。两相厌氧系统的pH值和碱度说明系统运行较为稳定。产酸相的有机酸中乙酸含量高于丙酸和丁酸,说明发酵末端产物以乙酸为主。在20天的试验周期内,污泥溶胞处理后、两相厌氧系统产甲烷相产气量累积产气量为1.2L,对照组只有375ml。气体中甲烷含量都在55%左右。该研究结果表明,好氧溶胞对污泥有破解能力,溶胞处理对两相厌氧中产酸相水解污泥细胞有明显的促进作用,提高了产酸相的水解酸化能力和效率。该研究对于利用生物溶胞途径提高污泥消化效率具有重要意义。 The actived sludge process has been used more and more extensively, but the procedure will lead to a large quantity of excess sludge. The treatment of Excess activated sludge has becomes a focuses not only for it is a seriously negative effect on environment but also for the costly disposal comes subsequently. The cell lysing bacterium was keeped in our lab to joined in the digestion of the excess activated sludge which was carrying at the same time with pre-processing of sludge to investigated the influence of cell lysing bacterium on excess sludge. There are two part in the method of cell lysing bacterium digesting sludge technology, the first, comparison of excess sludge digestion between anaerobic Cell-lysing Pretreatment and Conventional Aerobic Process. The sludge which was collected from San Wanyao disposal plant in Chengdu was thrown into the aerobic process system with cell-lysing bacterium, then, the indexes were detected to compare the difference between the cell-lysing bacterium in aerobic process and the traditional method to determine the influence of cell-lysing bacterium on aerobic process ; The second, the research on the sludge which was pro-treated with cell-lysing and aerobic digestion in the diphase of anaerobic digestion system. The system of cell-lysing combined with diphase of anaerobic digesting was created to compare to the diphase of anaerobic digested system, the changes of mass constituent was detected to study the ability and steady of disposal. Moreover, the research explored the difference among the types of fermentation. The efficacious of aerobic process was been proved. The result shows that the digesting rate of aerobic process with cell-lysing bacterium was higher than the traditional process. The ratio of sludge is reach to 40%~53%, which was far more effectively than the traditional process rate of 12%~20%. The TCOD of sludge which was treated with cell lysing bacterium and Aerobic Process is reach to 54.4%. Then, the sludge was thrown into the diphase of anaerobic digesting system. VSS/TSS of sludge is 0.62, HRT is 6d, the reduction of VSS is reach to 40.8%. The pH and alkalinity indicate the steady running of the diphase anaerobic digest system. In the acerbity phasing, the content of acetic acid was more than butanoic acid and propanoic acid in organic acid, it is demonstrated that the main composition of final production of fermentation was Acetic Acid. During the 20d of experiment, methylhydride phasing of diphase anaerobic digest system produced 1.2L methylhydride, however, there is only 375ml in CK, the content of methylhydride in all gas phase was around the rate of 55%. The average ratio of VSS was 18.53% in CK diphase anaerobic digest system which was far more unavailable than the mass sludge rate of 55.17%. Results demonstrated that aerobic cell-lysing digested the sludge, the treat of cell-lysing could obviously promoted the hydrolyzeing of sludge cell in the acerbity phasing, which improved the ability and rate of hydrolization and acidification. This study is significant in inhenceing the rate of sludge digestion in the method of cell-lysing bacterium.