943 resultados para Sludge disposal


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为解决炸药包殉爆销毁存在的诸多问题,适应新形势下部队训练保障要求,依据前人关于聚能装置设计经验和聚能效应原理,着重阐述了炸药、药型罩、炸高、外壳等重要参数设计原则及其选取依据,设计了一种用于危险弹药销毁的新型装置.为检验聚能引爆器侵彻引爆销毁危险弹药的能力,选取了5种典型弹药进行实弹销毁试验.试验结果表明:该装置能够引爆不同弹丸装药、不同弹体材料、不同弹丸壁厚的危险弹药,用于销毁危险弹药是可行的

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本文对无介体双室微生物燃料电池的产电性能进行了初步研究,并根据不同运行阶段产电性能的优劣,对其中微生物的差异性进行了比较分析。全文分为两个部分: 第一部分:以乙酸钠为阳极原料构建双室微生物燃料电池(MFC),研究不同阴极受体、外接电阻、乙酸钠浓度和pH等因素对电池产电性能的影响,研究结果表明:在500mL的阴阳极反应体系中,选用乙酸钠作为阳极底物,质量浓度为6.46 g/L, pH 7.0,接入500Ω外电阻,阴极电子受体选择高锰酸钾的情况下,微生物燃料电池产电性能最好,最大电功率密度达到294.72 mW/m2,库伦效率能达到25.87%。在确定最适外接电阻阻值的同时对MFC内阻进行测定,阻值为871.87Ω。 第二部分:微生物燃料电池运行中,比较以厌氧污泥作为接种源的第一阶段和只接入附着有大量微生物电极的第二阶段的产电性能,得出第二阶段产电性能优于第一阶段,最大电功率密度达到353.57mW/m2,比第一阶段提高58.85 mW/m2;库伦效率为39.35%,增幅达52%左右;针对微生物燃料电池运行过程中,底物CH3COONa可能存在其它的代谢途径,本实验进行了第二阶段产电性能与CH3COONa消耗率关系以及阳极液面上方气体成分和含量的研究,发现第二阶段50h前CH3COONa的大量消耗主要用于微生物的生长,在整个运行过程中,阳极液面上方含有CH4和CO2;对气体测定的同时还发现,振荡能增强电功率密度的输出;通过对电极上和污泥中微生物差异性分析得出,δ-变形菌纲、β-变形菌纲和拟杆菌门的菌种更适应微生物燃料电池的运行环境,能在电极上大量富集,提高电池的产电性能,只接入附着有大量微生物的电极能有效降低热袍菌纲的菌种数量,降低了CH3COONa的无为消耗,有效提高了电池的库伦效率。 Electricity production in the mediator-less two-chambered microbial fuel cell(MFC) was researched. Based on the result in the different operation phase in the MFC, the microbial diversity was analysed. The paper involved two parts: Part 1: A two-chambered microbial fuel cell (MFC) was constructed with high-concentration sodium acetate as fuel in the anode. The influence of different electron acceptors in the cathode, external resistance value, pH value and concentration of sodium acetate on electricity generation in MFC was investigated. The result showed that the maximum power density of 294.72 mW/m2 and the coulombic efficiency of 25.87% was achieved at sodium acetate concentration of 6.46 g/L, pH 7.0, external resistance 500Ωin the anode and when using potassium permanganate as electron acceptor in the cathode. While decided the value of resistor, we found that shaking has effect on electricity production in the MFC. Part 2: Comparing the electricity production in different operation phases when using anaerobic sludge as inoculum in the first phase and microbes in the anodic electrode as inoculum in the second phase, the result showed that electricity production in the second phase was more than that in the first phase, the maximum power density of 353.57 mW/m2 and the coulombic efficiency of 39.35% was achieved, 58.85 mW/m2 and 52% more than that in the first phase, respectively. According to the fact that CH3COONa might be metabolized in other pathway in the running process in the MFC, we determining the relationship between electricity production and CH3COONa consumption, and the gas content in the anode, we found that CH3COONa was mainly used for microbe growth before 50h, and the anode contained CH4 and CO2. At the same time, we found that shaking could improve power density. The analysis on diversity of microbe in the anodic electrode and anaerobic sludge showed that δ-proteobacterium, β-proteobacterium and Bacteroidetes adapted themselves to the running environment of MFC. The anode could enrich them to improve the electricity production while reduced the quantity of Thermotogales, which were obligately anaerobic organotrophs with a fermentative metabolism, to increase the coulombic efficiency effectively.

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本文从四川绵竹酒厂、成都市龙泉长安垃圾填埋场以及四川大学荷花池底的厌氧污泥中先后分离得到63株厌氧产氢菌,其中H-8、H-61、HC-10等16株产氢细菌产氢能力较高,HC-10的产氢能力最高,最大产氢量和最大产氢速率分别达到2840 ml H2/L培养基和25.39 mmol H2/g drycell·h,对HC-10进行生理生化鉴定和分子生物学鉴定,判定其为clostridium sp.,对HC-10的产氢条件进行了研究,结果表明,该菌的最适生长温度为35 ℃,最适生长初始pH为7,以葡萄糖为最佳碳源,以蛋白胨为最佳氮源,不利用无机氮源,其产氢发酵液相产物以乙醇和乙酸为主,其发酵类型属于乙醇型发酵。此外,以酒糟废液作为底物,进行了菌株HC-10的生物强化试验,研究表明,投加了HC-10的强化系统其产氢量比对照高出40.32%。 同时为了获得厌氧产氢菌的高效突变株,分别以产氢菌H-8和H-61为原始菌株进行微波诱变处理,对微波诱变参数进行了优化,考察了突变株的遗传稳定性、产氢特性及耐酸性。菌株H-8经过微波诱变得到5株高产氢突变株HW7、HW33、HW181、HW184、HW195,经多次传代表明HW195是稳定的高产突变株。突变株HW195具有较好的耐酸性,在pH值为2.8时仍能生长。通过间歇发酵实验,其最大产氢量和最大产氢速率分别达到2460 mL/L培养基和27.97 mmol H2/g drycell·h,比原始菌分别提高了50.75%和41.7%。菌株H-61经过微波诱变后选育得到的突变株HW-18,其最大产氢量和最大产氢速率分别达到2190 mL/L培养基和25.86 mmol H2/g drycell·h,比原始菌分别提高了23.03%和31.00%。 为了对比各种诱变方式对产氢菌产氢能力的影响,以厌氧产氢菌H-61为原始菌株,先后经亚硝基胍(NTG)、紫外(UV)诱变,选育得到1株高产突变株HCM-23。在葡萄糖浓度为10 g/L的条件下,其产氢量为3024 mL/L培养基,比原始菌株提高了69.89%;其最大产氢速率为33.19 mmol H2/g drycell·h,比原始菌株提高了68.14%。经过多次传代实验,稳定性良好。其发酵末端产物以乙醇和乙酸为主,属于典型乙醇型发酵。其最适产氢初始pH为6.5,最适生长温度为36 ℃,以蔗糖为最佳碳源。与原始菌株相比,突变株HCM-23的产氢特性发生了改变,如生长延滞期延长,可利用无机氮源等。 From anaerobic activated sludge, 16 strains of hydrogen producing bacteria were newly isolated. One of them named as HC-10 had the highest hydrogen producing capability, under the batch fermentative hydrogen production condition, the maximal hydrogen yield and hydrogen production rate was 2840 mL/L culture and 25.39 mmol H2/g drycell·h. It was identified as clostridium sp.HC-10 by 16S rDNA sequence analysis. Various parameters for hydrogen production, including substrates, initial pH and temperature, have been studied. The optimum condition for hydrogen producing of strain HC-10 were achieved as: initial pH 7.0, temperature 35 ℃, glucose as the favorite substrate, Moreover, using distiller's solubles wastewater as substrate, HC-10 strain was added in the biohydrogen producing system to research the bioaugmentation effection. The results showed that the hydrogen production of bioaugmentation system was 40.32% higher than the noaugmentation system. An anaerobic, hydrogen producing strain H-8 was irradiated by microwave to optimize the microwave mutagenesis condition, and to test the heredity, hydrogen-producing potential and aciduric of the mutants. An aciduric mutant named as HW195 with steady hydrogen-producing capability was obtained, which can grow at pH 2.8. Its capability of hydrogen production was tested in the batch culture experiments. The maximum hydrogen yield and hydrogen production rate was 2460 mL/L culture and 29.97 mmol H2/g drycell·h, which was 50.7% and 41.7% higher than those of the initial strain, respectively. When used the strain H-61 as original strain, a mutant named as HW18 was obtained. The maximum hydrogen yield and hydrogen production rate was 2190 mL/L culture and 25.86 mmol H2/g drycell·h, which was 23.03% and 31.00% higher than those of the initial strain, respectively. The results demonstrated that microwave mutagenesis could be used in the field of hydrogen producing microorganism. The hydrogen producing strain H-61 was used as an original strain which was induced by NTG and UV for increasing and the hydrogen production capability. One of the highest efficient H2-producing mutants was named as HCM-23 with its stable hydrogen production capability. which was tested in the batch culture experiments. With the condition of 10 g/L glucose, its cumulative hydrogen yield and hydrogen production rate was 3024 mL/L culture and 33.19 mmol H2/g drycell·h, 69.89%and 68.14% higher than that of the original strain, respectively. The terminal liquid product compositions showed that the mutant HCM-23 fermentation was ethanol type, while the original strain H-61 fermentation was butyric acid type. Varieties of parameters of hydrogen production fermentation were studied, including time, carbon source, nitrogen source, glucose concentration, glucose utilization, initial pH and incubation temperature had been studied, indicated the optimum condition of hydrogen production for the mutant HCM-23 as initial pH6.5, temperature 36 ℃, and the favorite substrate was sucrose. The hydrogen production characters of the mutant and the original strain were different, such as, the growth lag phase and the utilization of inorganic nitrogen source, etc. This work shows a good application potential of NTG-UV combined mutation in the biohydrogen production. And the hydrogen production mechanism and metabolic pathway should be explored furthermore.

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猪场废水COD浓度高、氨氮浓度高、悬浮物浓度高,已成为农村面源污染的主要来源,并严重威胁到农村饮用水安全。猪场废水氨氮浓度高、处理难度大,如何采用经济高效的方法,去除氨氮使其达到排放标准,一直是猪场废水处理中面临的重要难题。 厌氧氨氧化是近年受到国内外水处理研究者广泛关注的新型生物脱氮技术,具有不需要外加有机碳源、节省供氧量、降低能耗等优点。虽然国内外研究者对厌氧氨氧化过程的脱氮机理、厌氧氨氧化菌的生理生化特性等进行了多方面的研究,但已有的报道大多以模拟废水为研究对象,以猪场废水为研究对象的报道,在国内外文献中极少有报导。 本论文以猪场废水为主要研究对象,考察了猪场废水的亚硝化过程、厌氧氨氧化的启动过程,并对亚硝化和厌氧氨氧化联合用于猪场废水脱氮进行了探索。 1.论文首先研究了猪场废水的亚硝化过程,考察了废水水质和主要运行条件对亚硝化过程的影响。实验表明:(1)亚硝化阶段反应时间为8到10h时,出水中氨氮和亚硝酸盐浓度比可达到1:1~1:1.23,满足厌氧氨氧化反应对二者比例的要求;达到前述要求时,氨氮去除率达到58.3~65.6 %,亚硝化率在整个过程均保持在97 %以上,COD去除率在59.2~68.6 %;(2)曝气量(溶解氧)对亚硝化过程影响显著,随着曝气量增大,达到厌氧氨氧化要求的氨氮与亚硝酸盐氮浓度比例所需水力停留时间τ越短,pH出现明显下降的时间越短;(3)τ对应的pH在7.8~8.1之间,无需进行pH调节即可满足厌氧氨氧化反应对pH的要求;(4)氨氮和COD降解过程遵循一级反应动力学,氨氮和COD降解的速率常数分别为0.0656~0.0724 1/h和0.0491~0.0664 1/h。 2.在进行亚硝化过程研究的同时,以模拟废水为试验对象,进行厌氧氨氧化启动研究。以反硝化污泥和养殖厂储水池厌氧底泥的混合污泥作为接种污泥,历时大约100天,培育出具有厌氧氨氧化活性的污泥,氨氮和亚硝酸盐氮最高进水浓度分别为223.8 mg/L和171.4 mg/L,去除率最高分别达48%和41.5%,此时二者消耗比例为1.33:1。 3.在猪场废水的亚硝化研究完成和厌氧氨氧化过程初步启动成功后,在模拟废水中逐步加入猪场废水的亚硝化处理出水,逐步实现亚硝化和厌氧氨氧化的组合。亚硝化出水添加到厌氧反应器后,厌氧氨氧化反应仍可继续进行,且去除效率逐步提高。研究发现添加的亚硝化出水中携带的亚硝化细菌在厌氧氨氧化菌膜外层生长并累积,增加了厌氧氨氧化反应基质的传质阻力,妨碍了厌氧氨氧化效率的提高。 4.亚硝化-厌氧氨氧化实际工程应用探索中,生物接触氧化池可在有效去除废水中的有机物的同时实现亚硝化,出水中氨氮和亚硝酸盐比例平均为1.10,可满足后续厌氧氨氧化的要求;在适宜的进水浓度和温度下,ABR池出现了厌氧氨氧化启动的迹象;研究同时发现,水质的波动和气温的变化是工程中影响厌氧氨氧化菌活性的重要因素。 论文的主要创新点在于:(1)以猪场废水为研究对象,以实现厌氧氨氧化为目标,对亚硝化过程进行了比较详细的考察,获得了亚硝化出水满足厌氧氨氧化要求的工艺条件,通过对其COD和氨氮降解过程的考察,得出亚硝化阶段COD降解和氨氮去除的动力学模型;(2)对亚硝化-厌氧氨氧化处理猪场废水进行了探索,确立了影响其污染物去除率稳定的重要因素。 论文的上述研究成果,为厌氧氨氧化技术的实用性研究提供理论依据。 Piggery wastewater, which is characterized by high concentration of COD、ammonium and suspend substance, has become a most important source of non-point source pollution and also severely threats drinking water security in rural area. How to discharge piggery wastewater with the ammonium concentration meeting standard by economical and effective method? This is the most urgent problem in piggery wastewater treatment. As a new biological nitrogen removal technology, Anammox process has been paid more and more attention by researchers all over the world. Anammox has advantages of no need of organic carbon addition, low oxygen consumption and energy consumption. Plenty of investigations have been carried out to the mechanism, physiological and biochemical characteristic of bacteria about Anammox. Most of researches focused on synthetic wastewater, there is rare report about its application in piggery wastewater. In this paper,experimental studies were performed to investigate Sharon process in treatment of piggery wastewater,the start up process of Annammox using synthetic wastewater were studied, the feasibility of applying Sharon-Anammox process in the nitrogen removal of piggery wastewater was evaluated. 1. Sharon process of piggery wastewater was firstly investigated to analyze the effects of water quality and main running parameters, which meet the NH4+-N to NO2--N ratio requirement of successive Anammox. Results showed: (1)During Sharon Process,after 8~10 hours’ reaction the NH4+-N to NO2--N ratio in effluent reached 1:1.0~1:1.23, when the removal percentage of NH4+-N was 58.3~65.6 %, a semi-nitration rate of above 97 % was achieved during the process; meanwhile 59.2~68.6 % of the COD was also removed. (2)The aeration rate(oxygen) had obvious effect on the hydraulic retention time(τ) which met the NH4+-N to NO2--N ratio requirement of Anammox. As aeration rate increased, the hydraulic retention time(τ) was shortened. (3) The pH corresponding to τ was between 7.8 and 8.1, thus it needed no artificial adjustment. (4) The reduction of ammonia and COD followed the first-order reaction kinetics. The velocity constants of ammonia and COD were 0.0656~0.0724 1/h and 0.0491~0.0664 1/h, respectively. 2. The startup of Anammox process using the artificial wastewater was performed simultaneously with Sharon. The aim was to investigate the running parameters of Anammox and make foundation for the combination stage. By using the mixture of denitrifying sludge and anaerobic sludge in tank of the breeding factory, sludge of Anammox activity was cultivated in UASB after 100 days. The removal percentage of NH4+-N and NO2-N were up to 48% and 41.5%, respectively, when the NH4+-N and NO2-N influent concentration were 223.8 mg/L and 171.4 mg/L, respectively, the NH4+-N and NO2-N removal rate was 1.33:1. 3. After investigation of Sharon and startup of Anammox, effluent of Sharon process was added into the synthetic wastewater to combine Sharon and Anammox step by step. It took some time after the addition of Sharon effluent that Anammox reaction continued and the removal rate kept increasing. It indicated that nitrifying bacteria were carried by the Sharon effluent cumulated in the outer layer of Anammox. This enhanced transfer resistance of Anammox reaction and the increasing removal rate was restrained. 4. In the bio-contact oxidation pond of practical project, Sharon process were carried out successfully and organic compounds were removed effectively. An average NO2-N/ NH4+-N rate of 1:1.0 was achieved in the effluent, which met the requirement of successive Anammox. Under condition of suitable influent concentration and temperature, there was evidence that Anammox could start up in ABR. The variety of wastewater and temperature had great affects on Anammox activity in practical engineering. Innovation of this paper: (1) The Sharon process for treating piggery wastewater was discussed in details. Technological parameters that met requirement of Anammox were obtained. The dynamic models of COD and ammonium removal in the process were educed. (2) Sharon-Ananmmox for treatment of piggery wastewater was investigated, and the primary influencing factors was studied. This paper could be a theoretical consult for research of Anammox utility.

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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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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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本文研究了两种微生物及其组合沥取、回收用微生物法治理电镀铬废水产生的铬污泥中的铬。铬污泥富含C、N、O,含铬量为13%, 经X-光电子能谱分析铬以三价态(氢氧化铬)存在。二种微生物分别从一酸性矿水和酸性污泥中分离筛选得到,经鉴定为硫杆菌属 (Thiobacillus Beijerinek)的两个不同种,一为氧化亚铁硫杆菌(Thiobacillu ferrooxidans, TF), 另一为氧化硫硫杆菌 (Thiobacillus thiooxidans, TT)。研究并比较了不同微生物对污泥中铬的沥取能力,结果表明,TT菌沥取铬效率最高。振荡、动 态淋滤、静置等沥取方式经过研究表明动态淋滤为最佳,室温条件下(15-20℃),污泥浓度为20g/L时,总铬沥出率达60%时所需时 间:动态淋滤为48.5h,振荡和静置方式分别为91.22,81.6h。研究了不同温度、不同起始PH、不同污泥浓度及非成熟菌液对微生 物沥取能力的影响:(1) 沥取前期,温度对铬的沥出影响较大;微生物沥取反应基本属一级反应;温度与反应速率的关系基本符合 Arrhenius方程,但沥取后期这一特点并不突出。(2) 沥取液最适起始PH为菌液自然PH;PH值的人为改变将使铬的沥出大大降低。 (3) 污泥浓度与铬的沥出呈正相关,但浓度高于30g/L时,铬的沥出量不再增加。(4) 非成熟菌液沥出铬的能力较差,但沥取液中 微生物生长繁殖较为活跃。总结微生物沥取反应最佳沥取条件为:TT成熟菌液、污泥浓度10g/L、温度25-36℃、动态淋滤方式,此 时铬几乎可100%从污泥中沥出。经扫描电镜分析,沥取开始时,微生物紧密吸附于污泥颗粒表面上,表面紧密吸附为微生物发挥功 能提供了基础。微生物沥取污泥中铬的反应机理推测为:硫细菌代谢产硫酸或氧化Fe2+成Fe3+,利用酸,Fe3+ 及自身氧化酶系统 氧化污泥中Cr3+为Cr6+,Cr6+溶出结晶为CrO3。This paper has studied bioleaching and recovery of Chronium(Cr)from electroplating sludge by two consortum of bacteria and their combination, with sludge produced by microbiological process treating electroplating wastewater containing Cr as material. The share of Cr is 13% and its state is Cr (OH)3 in the sludge. One of the bacteria in the paper was isolated from acid sewage sludge and the other was from acid mineral water. The former was tested and determined as Thiobacillus ferroxidans(TF) and the latter was Thiobacillus thiooxidans(TT). Different microorganisms, responsible for the metal leaching activity, have great influence on the efficiency of leaching. The results showed that TT has biggest power. Experiments were conducted to examined effects of three different ways of leaching(Shaking, Down-leaching, Static-leaching). When temperature was in-door's (15-20℃)and concentration of the sludge was 20g/L, the bioleaching time required to reach 60% of Cr solubilization with the above three ways were 91.2, 48.5, 81.6h respectively. Down-leaching was proved to be the most efficient. The influence of different temperature, initial PH, concentration of the sludge and non-mature inoculum had been studied. The results obtained reveal that: (1) The variation of temperature is important during the time from initial to middle of leaching. The reaction of bioleaching belongs to first-order. The relation between the bioleaching rate constant(In k)and temerature can be expressed by Arrhenius function. (2) The fittest initial PH is the nature PH of mature inoculum. Any alteration with it could cause clearly negative effection. (3) The concentration of the sludge can make strong influence on the bioleaching efficiency. But when the concentration is above 30g/L, the increasing of Cr in the solution is little. (4) If non-mature inoculum acts as the bioleachin microorganism, little quantity of Cr would be gained from the sludge. But the micormass in the solution is very active. The results from electron microscope showed that microorganisms adhered to the surface of the sludge and the adherence was the first stage of the bioleaching. Some salts of Cr can be obtained afer the water of the bioleaching solution being evaporated. By analysing the results of experiment with X-Ray spectroscopy, the salt was identified as CrO3. The recovery rate of Cr is 78.4%.

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单宁是一种典型的有毒难降解污染物,在制革、造纸、制药、印染等行业废水中广泛存在,对水环境造成污染并且影响废水生物处理效果。本研究针对含单宁废水生物处理效率低、较高浓度时微生物受抑制且污泥容易膨胀等问题,采用超声和磁粉来强化含单宁废水生物处理,研究超声和磁粉对微生物活性、污染物去除及污泥沉降性能的影响,并对其作用机理进行了分析和探讨。 研究结果表明,活性污泥系统中单宁酸容积负荷可以达到1.8kgCOD/(m3·d),单宁酸和COD去除率分别达到85.2%和79.6%,但如果负荷进一步增大则微生物活性迅速降低。系统在pH 5~8、温度20~35℃、DO>1 mg/L的条件下具有较好的单宁酸降解效果和处理稳定性。单宁降解动力学参数为:μmax =0.208h-1;Ks=226mg/L;Ki=522mg/L;kd=0.0092h-1;Y =0.594。 磁粉对系统处理效果和污泥沉降性能有一定的促进作用,且效果要优于外磁场。适宜的磁粉粒径和投加量分别为0.05~0.15mm和1.0g/L,COD去除率比对照系统提高6.4%,SVI降低28.6%,污泥絮体结构紧密。磁粉强化主要是通过其对污泥菌胶团的凝聚、吸附作用以及对微生物活性的强化作用实现。 在适当强度(0.4W/cm2)和辐照时间(20min)的超声作用下污泥絮体和细胞膜通透性增大,酶分泌也增多,系统的COD去除率比对照提高了8.8%,单宁酶酶活提高了11%。但超声也使污泥絮体结构松散,沉降性能下降,SVI比对照系统升高9.3%。 由于污泥流失加剧导致污泥浓度相对较低,声磁联合强化系统相对于磁粉强化系统其处理效果并没有提高。但相对于单纯活性污泥系统,声磁联合作用下系统处理效果、污泥沉降性能以及系统运行稳定性都得到明显改善。本研究为难降解废水的生物处理提供了一个新的思路。 Tannins are typical refractory and toxic pollutants that commonly exist in wastewater from dye, medicine, paper and leather industries and cause many problems associated with environmental pollution and biological treatment of wastewater. Biological treatment efficiency of tannin-containing wastewater is usually low owing to its biological toxicity and low biodegradability, microbes are usually inhibited under high tannin concentration and sludge bulking frequently occurs. In this study, ultrasound and magnetic powder were used to improve the biological treatment performance of simulated tannic acid-containing wastewater. The effects of ultrasonic irradiation and magnetic powder on microbial activity, tannic acid degradation rate and sludge sedimentation were investigated. The augmentation mechanisms were analyzed and discussed. The experimental results showed that the microbes were prominently inhibited under high tannic acid concentration, but moderate degradation efficiency can be maintained under a tannic acid load of up to 1.8kgCOD/(m3·d), with the tannic acid degradation and COD removal percentage of 85.2% and 79.6% respectively. The highest degradation rates and treatment stability were achieved at pH range of 5~8, temperature range of 20~35℃ and DO concentration of above 1mg/L. The kinetic parameters were estimated, including: μmax =0.208h-1;Ks=226mg/L;Ki=522mg/L;kd=0.0092h-1;Y =0.594. The microbial activity, tannic acid degradation rate and sludge sedimentation were improved by adding Fe3O4 magnetic powder, and the augmentation performance was better than external magnetic field. The appropriate particle size and dosage of magnetic powder were found to be 0.05~0.15mm and 1.0g/L, respectively, under which the COD removal percentage was improved by 6.4% and SVI value decreased by 28.6%, and compact floc structure was observed. This was mainly caused by the flocculation and adsorption effects of magnetic powder against sludge floc and the stimulation of microbial activity under appropriate magnetic field. Under appropriate ultrasonic irradiation (ultrasonic intensity 0.4W/cm2, ultrasonic irradiation time 20min), the permeability of floc and cell membrane are improved, transfer of substrate and oxygen were reinforced; meanwhile, more enzyme were produced by microbes under the slight damage caused by ultrasound. However, the floc structure became loose under ultrasonic irradiation, leading to relatively poor sedimentation, with the SVI value 9.3% higher than the control system. Although the magnetic powder-ultrasonic irradiation combined augmentation system showed no improvement in treatment performance compared with sole magnetic augmentation system owing to its relatively low sludge concentration, it guaranteed the stable operation of system, meanwhile the tannic acid degradation and sludge sedimentation were significantly improved compared with sole activated sludge system. This study gives a new idea for biological treatment of refractory wastewater.

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随着化工行业的发展,大量有毒有害难降解有机物随工业废水的排放进入环境,这些物质能够在环境中长期存在、积累和扩散,通过食物链对动植物的生存及人类的健康造成不良影响。本文以苯酚、对氯硝基苯、氯苯和十六烷为模拟污染物,以前期研制的功能菌剂为对象,经过紫外线线诱变筛选出优于出发菌株的功能菌,对诱变后功能菌的理化性能进行了研究,对菌种进行了鉴定,在此基础上,就其相互之间的微生态关系进行研究,为混合发酵提供理论基础,并就其最佳发酵条件及发酵参数进行了研究,最后对发酵产品的性能进行了检测。目前,国内外有关功能菌剂的研究还存在多方面的不足,主要包括:①由于多菌种混合发酵过程较为复杂,各菌之间存在复杂的相互作用,影响因素较多,关于菌种之间的相互关系研究得很少,环境功能菌剂的发酵方法大多采用单独发酵后混合的方式。单独发酵对原材料、设备和能源的利用率较低,对于多菌种制剂发酵,在设备、能源和原材料的方面造成的浪费更大,将会大幅增加菌剂的生产成本,影响多菌种功能菌剂的发展;②功能菌剂生产过程的质量控制方面研究得较少;③功能菌剂产品的稳定性、抗冲击性能研究得较少,对环境微生物制剂的研究主要集中在菌种选育和培养条件优化方面。 通过本论文研究,得到以下主要结论。 (1)在紫外线诱变处理中,用紫外线对发生一定程度退化的出发菌株进行诱变处理后,六株具有高效降解性能的菌株被筛选出来,诱变筛选出的菌株形态和ERIC-PCR指纹图谱与出发菌株相比发生了明显改变;而且诱变后的菌株对目标难降解底物的降解能力均得到改善,其中,FPN、FCB、F14、FEm对目标底物的降解率提高了20%以上;诱变后菌株经过7次连续传代接种后,对目标难降解底物的降解率无显著变化,具有一定的遗传稳定性。并对诱变后的功能菌进行了初步的鉴定,这6株菌都分别是芽孢杆菌。 (2)对诱变后的功能菌相互之间的微生态关系进行了研究,通过抑菌实验、生长量以及基质消耗量的比较,确定它们之间的生长关系是无害共栖关系,可以进行混合发酵。 (3)对该功能菌剂进行发酵培养条件研究,结果表明发酵培养基的最佳成分(g/L):葡萄糖 31.0g/L、玉米粉10.0g/L、磷酸氢二钾1.0g/L、硫酸铵1.1g/L、硫酸镁0.55g/L。通过研究不同的培养条件对菌体生长和降解性能的影响,确定了最佳培养条件:培养基初始pH7.5;最适温度32℃;培养基装液量125mL(250 mL三角瓶),以及培养时间对降解性能的影响,培养20 h的产物对降解最为有利。通过研究添加不同目标污染物对菌体生长和降解性能的影响,确定了添加目标污染物的最佳量以及最佳时间:苯酚投加量:1.125 g/L,对氯硝基苯投加量:0.1 g/L;最佳投加时间为发酵培养开始后4 h。 (4)以摇瓶分批发酵最优条件为基础,对FPN、F10、FCB、FNa、F14 和 FEm进行了摇瓶分批发酵试验。以摇瓶分批发酵试验数据为依据,对功能菌剂分批发酵动力学进行了研究,建立了菌体生长和基质消耗的动力学模型,拟合模型能较好的反映功能菌剂分批发酵过程。 (5)功能菌剂和活性污泥协同作用,可以提高系统的生物降解能力,功能菌剂投加量为2%,新鲜活性污泥3500 mg/L,降解24 h条件下,功能菌剂和活性污泥的协同作用对COD的去除率和对照组相比,最多的提高了36.8%。功能菌剂和活性污泥协同作用以及活性污泥的单独作用,其生物降解过程均符合一级反应动力学过程,功能菌剂和活性污泥协同作用的生物降解动力学方程为:,相关系数97%。采用SBR运行方式,引入功能菌剂的SBR系统明显能够改善和提高生物降解的效率。与仅有活性污泥的系统相比,系统对COD的平均去除率可以提高27.1%,同时,系统的耐负荷冲击以及耐毒害冲击的性能比仅有活性污泥的SBR系统强,特别是负荷冲击对引入功能菌剂的SBR系统影响很小。仅有活性污泥的SBR系统经过负荷冲击和毒害冲击之后,不能恢复到冲击之前的水平,而且系统有效作用时间的周期比引入功能菌剂的SBR系统相比大大缩短,而引入功能菌剂的SBR系统处理效果较为稳定,恢复能力很强。 Along with the development of industries, many recalcitrant organic chemicals have been discharged into natural environments together with wastewaters and can exist in waters, soil and sediments for a long time without degradation. These haz-ardous substances, their byporducts and metabolizabilities can be highly toxic, mu-tagenic and carcinogenic, thereby threatening animals, plants and human health through food chain. Consequently the removal of these compounds is of significant interest in the area of wastewater treatment. In this dissertation, the phenol, hydro-quinone, chlorobenzene and hexadecane treated as the model pollutants, the func-tional microorganism agent was used as the starting strains, they treated with ultra-violet light, and then the mutant strains with high degradation ability were screened out and identified primarily, the relationship between these stains were studied, the medium composition and fermentation conditions were optimized, the degradation ability of the fermented production was tested. The literature survey indicates that the study of the microorganism agent is far from complete and more information is re-quired on following problems. 1, Because of the complexity of relationship in mixed fermentation and the complicated factors, the study is hardly to process.2, There is a lack of information on the quality control of the producing process .3, And there is a lack of information on the stability about the microorganism agent. In this dissertation, the main results of the present study could be summarized as follows: (1)The degenerate starting strains were treated with the ultraviolet light, and six mutant strains with high biodegradation ability were screened out by using the me-dium with selective pressure of model pollutants. The mutant strains had great changes in colonialmorphology and ERIC-PCR fingerprinting. And the mutant strains got obvious advantages over the starting strains in degradation ability and over 20% improvement of removal rates was achieved for FPN、FCB、F14 and FEm. The de-gradation ability of the mutant strains was stable after seven generations. After that, the mutant strains were primarily identified as bacillus respectively. (2) The relationship between these mutant strains was studied. By the compari-son of antibiosis effect, biomass and consumption of substrate, the relationships were neutralism and they could be mixed fermented. (3) The optimized cultivation conditions were as follows: glucose 31.0 g/L, corn power 10 g/L, K2HPO4 1.0 g/L, (NH4)2SO4 1.1 g/L, MgSO4 0.55 g/L, initial pH7.5, temperature 32℃, working volume 125 mL/250 mL, and cultivation time 20h (con-sidering the time effect on degradation ability), adding pollutants phenol (1.125 g/L) and hydroquinone (0.1 g/L) into the broth at 4 h after cultivation. (4) Based on the above optimum condition, the batch fermentation was per-formed with strains FPN, F10, FCB, FNa, F14 and FEm in shake flask. The batch fermentation kinetics was studied based on the experimental data. Two kinetic models were constructed which could reflect the regularity of growth and substrate consump-tion in the process of batch fermentation. (5) The co-operation of functional microorganism agent and activated sludge could raise biodegradation of system by adding some microorganism agent and 3500 mg/L fresh activated sludge. Bioaugumentation by the addition of high effective deg-radation culture enhanced the treatment effect of SBR system and the COD removal rate was increased by 20%-36.8%. Its biodegradation matched first-order dynamical reaction equation, and the reaction equation was ln0.2327.391ct=−+. The micro-organism agent had the effect of optimization to activated sludge micro-ecosystem. The SBR system adding 2% microorganism agent, the average COD removal rate of that was increased by 27.1% and stronger anti-shock ability to load and toxicant were achieved (compared with SBR system just adding activated sludge). Especially the load-shock has barely effect to the SBR system adding microorganism agent. After the load and toxicant shock, the SBR system just adding activated sludge couldn’t come back to original level and the activated sludge micro-ecosystem was frustrated. The applying of microorganism agent increased biological activity and system’s re-sistance ability to load shock and toxicant shock.

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垃圾卫生填埋是国内外城市垃圾的主要处置方法。垃圾渗滤液是渗入填埋场垃圾的降水混合垃圾降解过程中产生的物质而形成的混合物,是垃圾填埋场向环境排放的主要污染物。渗滤液由于其所含高浓度有机和无机污染物,且其中很多物质有生物毒性或难生物降解,难于治理。特别是到填埋晚期,渗滤液中高浓度的氨氮更是增加了治理的难度。渗滤液场外硝化-原位反硝化是填埋场氮管理的新途径。本文利用从环境中筛选出优势硝化功能菌对渗滤液中的高浓度氨氮进行生物硝化,经硝化后的渗滤液回灌至以垃圾柱模拟的生物反应器填埋场,在填埋场内实现原位反硝化。 上述目标通过以下两部分来实现: 第一部分:渗滤液场外硝化。首先从污水厂的硝化污泥中富集并筛选出硝化功能菌,在模拟氨氮废水中优化。将驯化的硝化功能菌接种于连续式完全混合反应器(CSTR)进行高氨氮渗滤液硝化研究。在200余天的连续运行中,反应器硝化和有机物去除效果良好。在最大氨氮负荷和有机物负荷分别为0.65 g N l-1 d-1 和3.84 g COD l-1 d-1时,氨氮和COD去除率分别高于99%和57%。实验过程中发现,游离氨(FA)和溶解氧(DO)浓度对反应器中亚硝酸盐的积累影响很大。 第二部分:渗滤液原位反硝化。本文利用一个垃圾填充柱模拟生物反应器填埋场,研究了硝化渗滤液回灌对垃圾降解的影响,和回灌的硝化渗滤液中TON(总氧化态氮)对填埋场生物反应器产甲烷作用的影响。最后利用变性梯度凝胶电泳(DGGE)分析了硝化渗滤液回灌对垃圾填埋场菌群结构的影响。结果表明:回灌的TON被完全还原,反硝化为主要反应,最大TON负荷为28.6 mg N kg-1 TS d-1。当垃圾柱TON负荷大于11.4 mg N kg-1 TS d-1时,出现了产甲烷抑制,抑制作用随TON负荷的增加而加强。在此过程中,反硝化逐渐代替产甲烷作用成为填埋场内垃圾降解的主要反应,且更多产生的是清洁的氮气,而非温室气体甲烷。直到实验结束时,回灌硝化渗滤液的垃圾柱的甲烷产量仅相当于对照的2.5%,并且回灌的硝化渗滤液还加速了填埋场垃圾的降解与稳定。通过DGGE进行菌群结构分析发现,由于TON对填埋场的长期作用,反硝化菌增多而产甲烷菌减少。 Landfill still remains the chief method for MSW management around the world. Leachate is a mixture of rainfall permeating through landfill and organic and inorganic matters generated during decomposition of the wastes in the landfills, characterized as highly complicated and refractory wastewater. Ex-situ nitrification and sequential in-situ denitrification represents a novel approach to nitrogen management at landfills. In the present paper, nitrification was carried out in a continuous stirred tank reactor (CSTR) inoculated with nitrifying bacteria which were isolated from municipal WWTP of Chengdu city. The nitrified leachate from CSTR was recirculated to a lab-scale municipal solid waste (MSW) column where in-situ denitrification took place. The above object was achived through two parts as following: First, ex-situ nitification of leachate. After acclimated in simulated wastewater for 3 month, nitrifying bacteria isolated from WWTP nitrifying sludge were added to the CSTR for nitrification. The results over 200 days showed that the maximum nitrogen loading rate (NLR) and the maximum organic loading rate (OLR) was 0.65 g N l-1 d-1 and 3.84 g COD l-1 d-1, respectively. The ammonia and COD removal was over 99% and 57%, respectively. Moreover, the effects of free ammonia (FA) and dissolved oxygen (DO) on nitrification were investigated. Second, in-situ denitrification was studied in a municipal solid waste (MSW) column. Variation of nitrified leachate and its effects on the decomposition of municipal solid waste (MSW) were studied in a lab-scale MSW column to which nitrified leachate was recirculated. Additionally, DGGE was employed to investigate the microbial community of both MSW columns. The results suggested: complete reduction of total oxidized nitrogen (TON) was obtained with maximum TON load of 28.6 mg N kg-1 TS d-1 and denitrification was the main reaction responsible. Methanogenesis inhibition was observed while TON load was over 11.4 mg N kg-1 TS d-1 and the inhibition was enhanced with the increase of TON load. Denitrification gradually took over methanogenesis to become the main reaction responsible for decomposition of MSW while nitrogen gas, a clean byproduct, was generated instead. Till the end of the experiment, the average weekly methane production in the denitrification column was as low as 2.5% of that of the control, and the rate of decompition and stability of MSW was accelerated by the recirculation of the nitrified leachate.Owing to long term exposure of nitrified leachate to landfill, denitrifying bacteria increased and methanogen decreased.

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本文从成都龙泉垃圾填埋场和宜宾造纸厂分离到耐酸性能优良的高温产甲烷菌RY3和中温产甲烷菌SH4,并将其与实验室现有的利用不同底物的产甲烷菌配伍组合成了复合菌剂。采用活性污泥作为固体附着物,研制出了固体产甲烷菌复合菌剂。 菌株RY3的pH耐受范围为5.5~10.5,最适生长pH 6.0~8.0。菌株RY3为革兰氏阳性,长杆状,多数单生,不运动;菌落浅黄色,形状近圆形;利用H2+CO2或甲酸盐作为唯一碳源生长,不利用乙酸盐,对氯霉素非常敏感。该菌最适生长温度为55℃~65℃,最适NaCl浓度为0~2%。根据形态和生理生化特性及16S rDNA序列分析将其初步定为热自养甲烷热杆菌(Methanothermobacter thermautotrophicus)。添加RY3菌液与仅添加厌氧污泥作为接种物相比一周内可使达到最大产甲烷速率所需时间缩短三分之二,甲烷总产量提高约1.8倍。菌株SH4的生长pH范围5.5~9.5,其对酸碱具有良好的适应性,培养3天后,在初始pH值为6.0~8.0的培养基中甲烷产量相差不大,且基本达到最大产量。SH4革兰氏染色阳性,短杆状,多数单生,不运动;菌落近圆形,微黄;利用H2+CO2或甲酸盐作为唯一碳源生长,不利用乙酸盐,对氯霉素非常敏感。SH4最适生长pH 为7.0,最适生长温度为35℃,最适NaCl浓度为0~1.5%。实验表明,添加SH4菌液与仅添加厌氧污泥作为接种物相比可使产甲烷启动时间缩短三分之一,甲烷总产量亦有大幅提高。从形态和生理生化特征以及16S rDNA序列分析表明SH4为嗜树木甲烷短杆菌(Methanobrevibacter arboriphilus)。 以活性污泥为附着物,与培养基和菌种经搅拌后厌氧发酵可得产甲烷菌固体复合菌剂。固体复合菌剂的pH耐受范围为5.5~9.5,温度耐受范围为15℃~65℃,表明其对环境的适应性较强。以猪粪为底物进行厌氧发酵,接种复合菌剂进行试验,以接种实验室长期富集的产甲烷厌氧污泥作为对照,在20℃时,发酵甲烷浓度与对照基本一致,但每日产气量优于对照,第15天时接种复合菌剂的发酵瓶每日产气量是对照的1.59倍;50℃时达到最大甲烷含量所需时间比对照缩短三分之二,三周内总产气量约为对照的2.7倍,甲烷总产量约为2.8倍。以不加接种物为对照,接种复合菌剂20℃时发酵甲烷含量达到50%约需2周,对照2周内甲烷含量最高仅为4.3%;50℃时接种复合菌剂发酵仅需约1周甲烷含量便可达50%,对照则至少需要2周。 In this paper, high-temperature Methanogen RY3 and middle-temperature SH4 were isolated from Chengdu Longquan refuse landfill and Yibin paper mill. They could be used to make compound inoculum that producing methane with the existing Methanogens utilized different substrate. With using anaerobic activated sludge be solid fixture, the process had been designed to produce solid compound inoculum. Strain RY3 possessed excellent capacity of acid and alkali-tolerant. The pH-tolerant scale of RY3 was 5.5~10.5 and its optimum pH value for growth was 6.0~8.0. RY3 was G+, long-rod shape, monothetic and nonmotile, the colony was pale yellow with suborbicular-shape. Formate or H2+CO2 but not acetate was utilized by RY3 as sole C-source, and it was very sensitive to chloramphenicol. Besides, strain RY3 grew fastest at 55℃~65 and 0℃~2% NaCl. Characteristics of modality and physiology with sequence analysis of the 16s rDNA gene of strain RY3 preliminarily showed that it was Methanothermobacter thermautotrophicus. The experiments indicated that the time which began to produce methane with the highest velocity could be shortened two third by adding RY3 in one week, and the total methane production also was 1.8 times than before. Strain SH4 possessed wide scale of growing pH(5.5~9.5)and excellent ability of acclimatizing itself to acid-alkali. The methane production had no apparent difference among those cultivated in different initial pH(6.0~8.0)after three days and equaled to the maximum production basically. Cells of SH4 were G+, short-rod sharp, monothetic and nonmotile. The colony was pale yellow with suborbicular-shape. Formate or H2+CO2 but not acetate was utilized by SH4 as sole C-source, and it was very sensitive to chloramphenicol. Besides, it grew fastest at pH 7.0,55 ℃~65 and 0℃~2% NaCl concentration. The experiment indicated the time that began to produce methane could be shortening one third by adding SH4. And the total methane production also rose apparently. Characteristic of modality and physiology with sequence analysis of the 16S rDNA gene of strain SH4 demonstrated it was Methanobrevibacter arboriphilus. The activated sludge was utilized as fixture, mixed with culture medium and inocolum, that the solid compound inoculum could be produced by anaerobic fermentation. The compound inoculum could grow between pH 5.5~9.5, 15℃~65. It demonstrated the compound inoculum ha℃ve great ability of adapting to circumstance. In the experiment that making pig manure be substrate and taking the anaerobic sludge producing methane that cultured in long term in laboratory to be comparison, the concentration of methane in fermentation added compound inoculum almost equal to the comparison at 20℃, but the volume of gas production could be a little higher. The gas production everyday inoculated compound inoculum was 1.59 times to comparison. The time that the concentration of methane to maximum could be shortening by two third by adding compound inoculum, and the total gas production was 2.7 times to comprison while the total methane production was 2.8 times. If take the no inoculum be the comprasion, anaerobic fermentation added compound inoculum made the concentration of methane to 50% in 2 weeks but the comparison only to 4.3% at 20℃. The time that the concentration of methane to 50% by adding compound inoculum only need 1 week, but the comparison need 2 weeks at 50℃.

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制革行业是轻工行业中仅次于造纸业的高耗水、重污染行业,作为劳动密集型行业,在解决大量人口就业问题的同时,也对所在地区环境造成了严重污染。目前我国制革行业每年排放废水8,000~12,000万吨,废水中含铬约3,500 t,SS为1.2×105 t,COD为1.8×105 t,BOD为7×104 t,对水体污染严重。 本研究在对厌氧酸化工艺进行研究、一级好氧处理段进行工艺比选研究的基础上,获得了匀质调节—SBBR—BAF的生物处理工艺,并依托该工艺进行了生物强化处理的研究,考察了菌剂的强化运行效果及其处理水回用的可行性。 研究表明,在进水COD>3,000 mg/L,厌氧酸化具有很好的抗冲击作用,保证了好氧工艺出水COD<200 mg/L;在进水COD<3,000 mg/L,可只通过好氧处理实现出水COD<200 mg/L。厌氧酸化停留时间选择不当,会导致厌氧出水硫化物浓度升高,严重影响好氧系统,会使好氧活性污泥因中毒而解絮。 研究表明,当进水COD为2,000~2,500 mg/L,NH4+-N为130~146 mg/L时,COD、NH4+-N去除率SBBR分别为93.8%~96.6%和14.5%~55.9%,SBR分别为88.8%~94.9%和13%~50.7%,表明SBBR优于SBR。同时,研究发现SBBR污泥增长率为0.05 kgVSS/kgCOD,仅为SBR0.57 kgVSS/kgCOD的8.8%。此外,研究发现SBBR在停止运行后经3个运行周期可回复原油能力,而SBR池经9个周期培养也不能恢复,说明SBBR恢复能力明显优于SBR。 研究表明,以匀质调节—SBBR—BAF为主的制革废水处理工艺,出水水质稳定,进水COD 801~2,834 mg/L、NH4+-N 87~203 mg/L,出水COD<80 mg/L、NH4+-N<10 mg/L,基本达到中水回用标准;操作简单灵活,没有污泥回流系统,污泥产率低,污泥处理费用低;工艺基本不需要添加化学药剂,既节约成本、又避免了二次污染;两级生物膜使得该工艺具有很强的耐冲击负荷能力,特别适合制革废水水质水量波动大的特点。 研究表明,高效菌对系统的启动具有一定的促进作用,强化系统生物膜6天可以成熟,对照系统生物膜9天可以成熟。同时高效菌能加速COD降解,缩短停留时间,强化系统6~8 h可使COD<200 mg/L,对照系统8~10 h可使COD<200 mg/L。长期运行表明,强化系统的SBBR在COD和NH4+-N的去除率都优于对照系统的SBBR。最终出水COD强化系统平均为53 mg/L、对照系统为74 mg/L。在模拟循环过程中,强化系统均有更高的稳定性。可实现8次理论循环,而对照系统只能实现4次理论循环。 研究表明,通过合理的工艺设计,可以实现猪皮制革废水达到《污水综合排放标准GB8976-1996》一级标准,同时满足工厂部分用水要求。通过添加高效微生物,可提高生物处理系统处理能力,使处理水能够满足工厂的多次回用。 As a labour-intensive industry, tanning has created large amount of working opportunities as well as caused severe contamination to environment. And it is one of the highest water-consuming and polluting industry, only second to manufacturing. At present time, Chinese leather industry emits wastewater about 80,000,000~120,000,000 t annually, which contains chromium about 3,500 t, SS 1.2×105 t, COD 1.8×105 t, BOD 7×104 t and ambient riverhead has been polluted greatly. Based on the research of anaerobic acidification and comparison of SBBR and SBR, biotreatment process (Homogenization—SBBR—BAF) had been established to amend the disadvantages of traditional sewage treatment such as too much sludge, high cost of advanced treatment and NH4+-N can not reach the emission standard. Research on the bioaugmentation was also been carried out. Researches showed, when COD of influent was beyond 3,000 mg/L, anaerobic acidification could resist strong impact, thus COD of effluent was less than 200 mg/L; when COD of influent was less than 3,000 mg/L, only throughout aerobic sewage treatment could COD of effluent beless than 200 mg/L. False residence tiome of anaerobic acidification would lead to the higher effluent concentration of sulfide and disintegration of aerobic activated sludge. Researches showed SBBR worked a better than SBR: when influent between 2,000 and 2,500 mg/L, NH4+-N between 130 mg/L and 146 mg/L, COD, NH4+-N removal rate of SBBR was 93.3%~96.6%, 14.5%~55.9% respectively while COD, NH4+-N removal rate of SBR was 88.8%~94.9%, 13%~50.7% respectively. Sludge growth rate of SBBR was 8.8% of that of 0.05 kgVSS/kgCOD. Besides, SBBR could recovered after 3 operating periods while SBR worked no better after 9 operating periods.Therefore, SBBR excelled SBR. Researches showed, effluent quantity of tannery wastewater treatment process (Homogenization—SBBR—BAF) was stable. When COD of influent was between 801 and 2,834 mg/L, NH4+-N was between 87 mg/L and 203 mg/L, COD of effluent was less than 80 mg/L, NH4+-N was less than 10 mg/L, which achieved the standard of reuse. This biotreatment was featured in low cost, easy and flexible management, less sludge, no inverse sludge system. Besides, this technique required no chemical, which could lower the cost and avoid secondary pollution. Great resistant of impact due to two membranes and was suitable for tannery wastewater which was featured by fluctuation of influent quality and quantity. Researches showed effective microorganisms promotes the startup of the process.Biofilm in the bioaugmentation process matured with 6 days while biofilm in normal process matured with 9 days. Effective microorganisms could accelerate the degradation of COD and shorten the residence time. Aggrandizement system could make COD<200 mg/L with 6 to8 hours while cntrolling system could make COD<200 mg/L with 8 to 10 hours. Long-term operating shows that SBBR in the bioaugmentation system worked better than the normal system in the treatment of COD and NH4+-N. The average COC of effluent in bioaugmentation system was 53 mg/L, normal system was 74 mg/L. In the simulative circulation process,aggrandizement process, which could fulfill 8 times theoretical circulation, works more stably than controlling process which could only fulfill 4 times theoretical circulation. Researches showed that reasonable design could make the wastewater meet the first grade of discharging standard of National Integrated Wastewater Discharge Standard (GB8976-1996), and partially meet the demand of water using of the factory. Adding effective microorganisms could enhance the biotreatment and make the effluents reuse many times.