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排序方式: 共有2462条查询结果,搜索用时 31 毫秒
81.
Continuous hydrogen production using upflow anaerobic sludge blanket reactors: effect of organic loading rate on microbial dynamics and H2 metabolism 下载免费PDF全文
82.
UASB+MBR+NF处理焚烧垃圾渗滤液的设计及运行 总被引:1,自引:0,他引:1
介绍了UASB+MBR+NF工艺处理某垃圾焚烧厂渗滤液的工艺流程、构筑物设计参数及运行情况。运行结果表明,该工艺对垃圾渗滤液具有较高的去除率,COD、BOD5、NH3-N、SS的去除率分别高达99.84%、99.94%、99.28%、99.83%。处理后出水的各项指标可以达到《污水综合排放标准》(GB 8978—1996)中的一级排放标准。采用该工艺去除1 kg COD需要花费0.57元。与城市污水厂生活污水的运行费用相比,该工艺具有较好的经济性。 相似文献
83.
84.
污水厌氧处理系统中溶解性微生物产物的研究进展 总被引:1,自引:0,他引:1
污水厌氧处理系统中产生的溶解性微生物产物(SMP)因其自身的性质、潜在危害性等逐渐引起国内外学者的重视。综述了国内外对厌氧SMP的研究成果,系统阐述了厌氧SMP的性质及影响其产生的运行参数。对其生成与降解数学模型的发展进行了综述。最后对今后厌氧SMP的研究方向作出了展望。 相似文献
85.
Noori M. Cata Saady Subba Rao Chaganti Jerald A. Lalman Sathyanarayanan S. Veeravalli Saravanan R. Shanmugam Daniel D. Heath 《International Journal of Hydrogen Energy》2012
The effects of lauric (LUA), myristic (MA), palmitic (PA), and a mixture of myristic:palmitic (MA:PA) acids on hydrogen (H2) production from glucose degradation using anaerobic mixed cultures were assessed at 37 °C with an initial pH set at 5.0 and 7.131 mM of each acid. The maximum H2 yield (2.53 ± 0.18 mol mol−1 glucose) was observed in cultures treated with PA. A principal component analysis (PCA) of the by-products and the microbial population data sets detected similarities between the controls and PA treated cultures; however, differences were observed between the controls and PA treated cultures in comparison to the MA and LUA treated cultures. The flux balance analysis (FBA) showed that PA decreased the quantity of H2 consumed via homoacetogenesis compared to the other LCFAs. The control culture was dominated by Thermoanaerovibrio acidaminovorans (60%), Geobacillus sp. and Eubacterium sp. (28%), while Clostridium sp. was less than 1%. Treatment with PA, MA, MA:PA, or LUA increased the H2 producers (Clostridium sp. and Bacillus sp.) population by approximately 48, 67, 86, and 86%, respectively. 相似文献
86.
Ecofriendly manure anaerobic digestion assisted by soluble bio‐based substances obtained from anaerobic digestion,composting and chemical hydrolysis of urban bio‐wastes. A step toward the integration of urban and agriculture waste management 下载免费PDF全文
87.
Biological treatment of groundwater with a high hexavalent chromium content under anaerobic and anoxic conditions 下载免费PDF全文
88.
In this study,an up-flow anaerobic sludge blanket(UASB) reactor was applied to treat the high salinity wastewater from heavy oil production process.At a HRT of ≥24 h,the COD removal reached as high as 65.08% at an influent COD ranging from 350mg/L to 640mg/L.An average of 74.33% oil reduction was also achieved in the UASB reactor at an initial oil concentration between 112mg/L and 205mg/L.These results indicated that this heavy oil production related wastewater could be degraded efficiently in the UASB reactor.Granular sludge was formed in this reactor.In addition,two models,built on the back propagation neural network(BPNN) theory and linear regression techniques were developed for the simulation of the UASB system performance in the oily wastewater biodegradation.The average error of COD and oil removal was-0.65% and 0.84%,respectively.The results indicated that the models built on the BPNN theory were wellfitted to the detected data,and were able to simulate and predict the removal of COD and oil by the UASB reactor. 相似文献
89.
90.
Craig Frear Zhi‐Wu Wang Chenlin Li Shulin Chen 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(1):145-152
BACKGROUND: There remain technological deficiencies in the economical anaerobic digestion of the entire flow of flushed dairy manure on farms within cold climates. In order to develop an anaerobic digester tailored for this purpose, this study investigated the distributions of biomass and biogas generated in three particle‐size‐characterized zones of flushed dairy manure. RESULTS: Results demonstrate that comparable biogas generations are equally distributed between the solids and liquid phases of flushed dairy manure, implying that at least 50% of methane generation might be lost when utilizing existing processes that only selectively handle the liquid or solids phases. Microscopic and kinetic studies show that the majority of microorganisms in the manure are attached to the surface of undigested dairy manure fibrous solids. In particular, greater than 70% of acetate‐utilizing methanogens were found closely associated with the indigestible solids. This high microbial affinity to the dairy manure solids phase can be traced back to the selection pressure driven bacterial immobilization mechanism in cattle rumen. CONCLUSION: This study shows that dairy manure fibrous solids have the potential to act as effective natural biomass carriers for high rate and simultaneous methanation of both solids and liquid phases of flushed dairy manure in one digester. Copyright © 2010 Society of Chemical Industry 相似文献