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51.
硫化物生物氧化脱硫技术研究现状   总被引:4,自引:0,他引:4  
苏静 《环境技术》2006,24(1):26-28,46
介绍了近年来国内外硫化物生物氧化为单质硫的各种脱硫技术.分析总结了硫化物生物氧化为单质硫工艺的各种影响因素,包括氧硫比、溶解氧浓度、硫化物浓度、化学氧化、微生物菌种、pH值、温度等因素.提出了生物氧化脱硫技术的发展前景.该技术将脱硫和单质硫的回收和为一体,是一种安全、低成本将含硫废液变废为宝的工艺技术.  相似文献   
52.
玉米芯为碳源实现酸性矿山废水生物处理   总被引:9,自引:0,他引:9  
引入了一种新的碳源——玉米芯,对SRB法处理酸性矿山废水进行了更加深入的探索,分析了各种参数条件对s暖一还原效果的影响,确定了常温下这种碳源所需要的最适宜工况条件,探讨了硫酸盐矿山废水的水质资源化问题,并对山西矿山废水的生物治理进行了可行性实验验证。实验证明,玉米芯为碳源时,矿山废水中SO^2-4的出水值可达221.1mg/L,金属离子的浓度也都达到了生活饮用水的质量标准,所以玉米芯可作为酸性矿山废水资源化生物处理的合适有效碳源。  相似文献   
53.
ABSTRACT: Surface water impairment by fecal coliform bacteria is a water quality issue of national scope and importance. In Virginia, more than 400 stream and river segments are on the Commonwealth's 2002 303(d) list because of fecal coliform impairment. Total maximum daily loads (TMDLs) will be developed for most of these listed streams and rivers. Information regarding the major fecal coliform sources that impair surface water quality would enhance the development of effective watershed models and improve TMDLs. Bacterial source tracking (BST) is a recently developed technology for identifying the sources of fecal coliform bacteria and it may be helpful in generating improved TMDLs. Bacterial source tracking was performed, watershed models were developed, and TMDLs were prepared for three streams (Accotink Creek, Christians Creek, and Blacks Run) on Virginia's 303(d) list of impaired waters. Quality assurance of the BST work suggests that these data adequately describe the bacteria sources that are impairing these streams. Initial comparison of simulated bacterial sources with the observed BST data indicated that the fecal coliform sources were represented inaccurately in the initial model simulation. Revised model simulations (based on BST data) appeared to provide a better representation of the sources of fecal coliform bacteria in these three streams. The coupled approach of incorporating BST data into the fecal coliform transport model appears to reduce model uncertainty and should result in an improved TMDL.  相似文献   
54.
利用微生物技术治理煤矿瓦斯的研究展望   总被引:3,自引:1,他引:3  
目前,我国的煤矿瓦斯防治技术主要为通风、抽放等物理方法,该类方法仍不能完全满足防治煤矿瓦斯灾害的安全要求。笔者提出一种治理煤矿瓦斯的新思路,采用一种新的控制方法,试图通过生物技术使瓦斯涌出量减少,防治煤矿瓦斯灾害。为此,对应用微生物技术治理煤矿瓦斯的可行性进行了分析,简单介绍了甲烷氧化菌的氧化机理及其在其他领域的应用,并通过初步试验对甲烷氧化菌降解煤样瓦斯的效果进行了测定,从而对其有了感性的认识,在已有的对甲烷氧化菌的研究和初步试验的基础上,对应用甲烷氧化菌解决煤矿瓦斯危害进行了展望。  相似文献   
55.
稠油污水生化性处理技术研究   总被引:1,自引:0,他引:1  
为了探讨稠油污水能否使用生物法处理,以生活污水和农药厂生化池原菌种经过诱导驯化,分别培养了可以在稠油污水中生长的好氧菌种革兰氏阴性菌G-1和厌氧菌种革兰氏阴性菌G-2.以G-2和G-1对稠油污水进行顺序处理,可使其BOD5/CODCr达到0.26;采用SBR法对新疆稠油污水放大处理试验的结果:COD降至150 mg/L以下,各项指标达到GB8978-1998二级排放标准.  相似文献   
56.
In Massachusetts, the Charles River Watershed Association conducts a regular water quality monitoring and public notification program in the Charles River Basin during the recreational season to inform users of the river's health. This program has relied on laboratory analyses of river samples for fecal coliform bacteria levels, however, results are not available until at least 24 hours after sampling. To avoid the need for laboratory analyses, ordinary least squares (OLS) and logistic regression models were developed to predict fecal coliform bacteria concentrations and the probabilities of exceeding the Massachusetts secondary contact recreation standard for bacteria based on meteorological conditions and streamflow. The OLS models resulted in adjusted R2s ranging from 50 to 60 percent. An uncertainty analysis reveals that of the total variability of fecal coliform bacteria concentrations, 45 percent is explained by the OLS regression model, 15 percent is explained by both measurement and space sampling error, and 40 percent is explained by time sampling error. Higher accuracy in future bacteria forecasting models would likely result from reductions in laboratory measurement errors and improved sampling designs.  相似文献   
57.
Biological treatment of clogged emitters in a drip irrigation system   总被引:1,自引:0,他引:1  
This study was conducted to investigate microbial organisms that can be used for preventing clogging in drip irrigation systems caused by biological factors. A total of 25 fungi isolate and 121 bacterial strains were isolated from water samples collected from drip irrigation systems in tomato greenhouses in the eastern Anatolia region of Turkey in the spring season of 2001. Biological clogging of emitters in a model drip irrigation system was experimentally caused by application of the microorganisms (fungi and bacteria) isolated in the study. Three antagonistic bacterial strains in the genus Bacillus spp (ERZ, OSU-142) and Burkholdria spp (OSU-7) were used for treatment of biological clogging of the emitters. The results showed that the antagonistic bacterial strains tested have the potential to be used as anti-clogging agents for treatment of emitters in drip irrigation system. This is the first study that demonstrated that antagonistic microorganisms can be utilized for treatment of clogging in drip irrigation systems.  相似文献   
58.
This work was aimed at studying the response of soil non-spore-forming actinobacterial strain Arthrobacter agilis Lush 13 to changing natural conditions, such as nutrient availability and the presence of degradable and recalcitrant aliphatic and aromatic substrates. The A. agilis strain Lush13 was able to degrade octane, nonane, hexadecane, benzoate, phenol, and 2,3-, 2,4-, 2,5-, 2,6-dichlorophenols, but not grew on 3,4-dichlorophenol, 2,3,4-, 2,4,5-, 2,4,6-trichlorophenol (TCP), pentachlorophenol (PCP), 2-chlorobenzoate, 3-chlorobenzoate, 3,5-dichlorobenzoate, 2,4-dichlorobenzoate. Under growth-arresting conditions due to nitrogen- or multiple starvation or recalcitrant (non-utilizable) carbon source, the studied strain preserved viability for prolonged periods (4–24 months) due to transition to dormancy in the form of conglomerated small and ultrasmall cyst-like dormant cells (CLC). Dormant cells were shown to germinate rapidly (30 min or later) after removal of starvation stress, and this process was followed by breakdown of conglomerates with the eliberation and further division of small multiple actively growing daughter cells. Results of this study shed some light to adaptive capabilities of soil arthrobacters in pure and polluted environments.  相似文献   
59.
在牛粪干式厌氧消化过程中,通过添加不同挥发酸(乙酸、丙酸、丁酸),考察消化稳定阶段,挥发性脂肪酸的分布特征,挥发性脂肪酸酸组成变化对硫酸盐还原菌(SRB)的影响,微生物种群组成和种群间关系。实验结果表明,挥发性脂肪酸对SRB还原速率的贡献依次为:丙酸丁酸乙酸。相比乙酸和丁酸,添加一定量的丙酸,更有利于激活SRB的活性,从而加强SRB与产甲烷菌(MB)的种间协同,保证厌氧系统的稳定运行。  相似文献   
60.
• The SRAO phenomena tended to occur only under certain conditions. • High amount of biomass and non-anaerobic condition is requirement for SRAO. • Anammox bacteria cannot oxidize ammonium with sulfate as electron acceptor. • AOB and AnAOB are mainly responsible for ammonium conversion. • Heterotrophic sulfate reduction mainly contributed to sulfate conversion. For over two decades, sulfate reduction with ammonium oxidation (SRAO) had been reported from laboratory experiments. SRAO was considered an autotrophic process mediated by anammox bacteria, in which ammonium as electron donor was oxidized by the electron acceptor sulfate. This process had been attributed to observed transformations of nitrogenous and sulfurous compounds in natural environments. Results obtained differed largely for the conversion mole ratios (ammonium/sulfate), and even the intermediate and final products of sulfate reduction. Thus, the hypothesis of biological conversion pathways of ammonium and sulfate in anammox consortia is implausible. In this study, continuous reactor experiments (with working volume of 3.8L) and batch tests were conducted under normal anaerobic (0.2≤DO<0.5 mg/L) / strict anaerobic (DO<0.2 mg/L) conditions with different biomass proportions to verify the SRAO phenomena and identify possible pathways behind substrate conversion. Key findings were that SRAO occurred only in cases of high amounts of inoculant biomass under normal anaerobic condition, while absent under strict anaerobic conditions for same anammox consortia. Mass balance and stoichiometry were checked based on experimental results and the thermodynamics proposed by previous studies were critically discussed. Thus anammox bacteria do not possess the ability to oxidize ammonium with sulfate as electron acceptor and the assumed SRAO could, in fact, be a combination of aerobic ammonium oxidation, anammox and heterotrophic sulfate reduction processes.  相似文献   
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