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Microbial removal of sulfur dioxide from a gas stream 总被引:10,自引:0,他引:10
Jan Gasiorek 《Fuel Processing Technology》1994,40(2-3):129-138
A study of the feasibility of utilizing the Thiobacillus ferrooxidans or Desulfovibrio desulfuricans bacterium for microbial removal of sulfur dioxide from flue gases has been carried out. Sulfur dioxide may be readily reduced to H2S by contact with sulfate-reducing microorganisms in which Desulfovibrio desulfuricans were dominant in the first stage. The H2S was then oxidized to sulfur by the ferric sulfate in a second stage where ferrous ions were regenerated. These results were compared to microbial oxidation of SO2 from flue gases to sulfate by Thiobacillus ferrooxidans. The mechanisms for the reduction of SO2 to H2S in the presence of Desulfovibrio desulfuricans and the oxidation of SO2 to H2SO4 in the presence of ferric sulfate and Thiobacillus ferrooxidans are discussed. Sulfuric acid or gypsum CaSO4 · 2H2O are byproducts from microbial flue gas desulfurization. 相似文献
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建筑类项目节能评估除体现全面性和深度外,还要针对建筑用能特点进行分析,作为评估结论的重要依据。在编制建筑类项目节能评估报告过程中,总结了该类型报告的主要内容,分析了一些容易出现的问题,并提出两点建议,以期对建筑类项目节能评估报告的编制提供一定的借鉴作用。 相似文献
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回归分析法、弹性系数法、指数平滑法、移动平均法等是市场分析预测中常用的方法。本文介绍了其中的回归分析法,并就其在水泥市场预测中的具体应用进行了探讨。选取了四川省1988-2002年全社会固定资产投资与水泥需求量作为两个变量,验证了这两个变量之间的相关关系及相关程度,在确立了因变量(Y)和自变量(X)之后,通过回归检验并建立回归模型来分析预测了四川省2010年的水泥需求的点预测值及置信区间预测值。 相似文献
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The present study was carried out to asses performance of a Pd-monolith downflow bubble column (DBC) reactor, and compare it with that of the slurry and the fixed bed DBC. The selective hydrogenation of butyne-1,4-diol to cis-2-butene-1,4-diol over palladium catalyst was chosen as a model reaction. In principle, the monolith DBC allowed the reaction to take place under kinetic control regime. Comparison with DBC employing 5% Pd/C powder and 1% Pd-on-Raschig ring catalysts revealed a better performance of the monolith DBC (1% Pd loading) with advantage of smaller reaction volume and intensified reaction rate. In the monolith DBC, improved hydrogen transport was possible, as the interface between bubbles and the channel wall was very thin, thus, the length of the diffusion path was very short. In addition, the interfacial surface area at both gas–liquid and liquid–solid interface in the monolith was also very high. The reaction kinetics was well represented by the Langmuir–Hinshelwood mechanism. As an alternative to conventional three-phase reactors, the monolith DBC was simple due to its inherent characteristic operation and no specially designed device. 相似文献
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In the present investigation, a microbial consortium consisting of four bacterial strains was selected for the treatment of pharmaceutical industry wastewater. The consortium was immobilized on a natural support matrix-Luffa and used for the treatment of real-time pharmaceutical wastewater in batch and continuous processes. The batch process was carried out to optimize the culture conditions and monitor the enzymatic activity. An array of enzymes such as alcohol dehydrogenase, aldehyde dehydrogenase, monooxygenase, catechol 2,3-dioxygenase and hydroquinol 1,2-dioxygenase were produced by the consortium. The kinetics of the degradation in the batch process was analyzed and it was noted to be a first-order reaction. For the continuous study, an aerobic fixed-film bioreactor (AFFBR) was utilized for a period of 61 days with variable hydraulic retention time (HRT) and organic loading rate (OLR). The immobilized microbes treated the wastewater by reducing the COD, phenolic contaminants and suspended solids. The OLR ranged between (0.56 ± 0.05) kg COD·m-3 d-1 to 3.35 kg COD·m-3·d-1 and the system achieved an average reduction of 96.8% of COD, 92.6% of phenolic compounds and 95.2% of suspended solids. Kinetics of the continuous process was interpreted by three different models, where the modified Stover Kincannon model and the Grau second-order model proved to be best fit for the degradation reaction with the constant for saturation value, KL being 95.12 g·L-1·d-1, the constant for maximum utilization of the substrate Umax being 90.01 g·L-1 d-1 and substrate removal constant KY was 1.074 d-1 for both the models. GC-MS analysis confirmed that most of the organic contaminants were degraded into innocuous metabolites. 相似文献
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基于齿轮箱广泛应用于机械设备的现状,满足企业对于其运行状态评估的现实需求,研究设计了针对齿轮箱监测和诊断的平台系统,以温度、振动等多源指标实时监控齿轮箱运行状况,并基于专家系统对异常数据进行诊断与反馈。以J2EE平台和SSH三层架构进行系统开发,通过底层调用MySQL、界面层运用ECharts对数据进行操作;以Jess引擎作为核心推理模块,建立基于孤立森林与模糊推理的专家系统。该系统可实时地显示齿轮箱运行数据,并完成对异常数据的诊断反馈,能够有效地应用于实际工业领域。 相似文献
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