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941.
To improve the efficiency of the carbon dioxide cycling process and to reduce the regeneration energy consumption, a sterically hindered amine of 2-amino-2-methyl-1-propranol (AMP) was investigated to determine its regeneration behavior as a CO_2 absorbent. The CO_2 absorption and amine regeneration characteristics were experimentally examined under various operating conditions. The regeneration efficiency increased from 86.2% to 98.3% during the temperature range of 358 to 403 K. The most suitable regeneration temperature for AMP was 383 K, in this experiment condition, and the regeneration efficiency of absorption/regeneration runs descended from 98.3% to 94.0%. A number of heat-stable salts (HSS) could cause a reduction in CO_2 absorption capacity and regeneration efficiency. The results indicated that aqueous AMP was easier to regenerate with less loss of absorption capacity than other amines, such as, monoethanolamine (MEA), diethanolamine (DEA), diethylenetriamine (DETA), and N-methyldiethanolamine (MDEA). 相似文献
942.
Electrochemical dechlorination of chloroform in neutral aqueous solution was investigated using palladium-loaded electrodes at ambient temperature. Palladium/foam-nickel (Pd/foam-Ni) and palladium/polymeric pyrrole film/foam-nickel (Pd/PPy/foam-Ni) composite electrodes which provided catalytic surface for reductive dechlorination of chloroform in aqueous solution were prepared using an electrodepositing method. Scanning electron microscope (SEM) micrographs showed that polymeric pyrrole film modified the electrode-surface characteristics and resulted in the uniform dispersion of needle-shaped palladium particles on foam-Ni supporting electrode. The experimental results of dechlorination indicated that the removal efficiency of chloroform and current efficiency in neutral aqueous solution on Pd/PPy/foam-Ni electrode could be up to 36.8% and 33.0% at dechlorination current of 0.1 mA and dechlorination time of 180 min, which is much higher than that of Pd/foam-Ni electrode. 相似文献
943.
944.
影响曝气生物滤池硝化性能的因素 总被引:1,自引:0,他引:1
对影响曝气生物滤池硝化性能的因素进行分析,并在对目前相关研究资料分析综合的基础上,提出了优化曝气生物滤池硝化性能的控制方法以及工艺参数的适宜范围:BAF的滤料粒径2—3mm为宜,BAF运行应尽可能地使用较大的滤速,适宜的气水比为3:1,温度为25—30℃,填料层的高度2m左右比较适宜,不需要太高。对于去碳和硝化作用在同一滤池内进行的BAF,进水有机负荷(BOD)应该低于3.0kg/(m^3·d),而对于两段BAF,应控制去碳滤池出水的COD浓度小于60mg/L。 相似文献
945.
环境规划是环境管理工作的重要内容之一,环境规划的目标是环境保护与经济协调发展的具体结合点。为使制定的规划能够可行,在规划的整个过程中公众参与是非常重要的。文章基于对中国目前环境规划中的公众参与存在的不足之处的简要论述,对影响环境规划公众参与有效性的因素进行了初步的探讨,指出公众参与的制度、对象、时间、形式、内容的设计、解决矛盾的能力、参与公众的热情等是影响中国环境规划公众参与有效性的主要因素,并提出了一些提高中国环境规划公众参与有效性的建议。 相似文献
946.
Field experiment on biological contact oxidation process to treat polluted river water in the Dianchi Lake watershed 总被引:1,自引:0,他引:1
Lu Li Shuguang Xie Hui Zhang Donghui Wen 《Frontiers of Environmental Science & Engineering in China》2009,3(1):38-47
In this study two types of biological contact oxidation processes (BCOP), a step-feed (SBCOP) unit and an inter-recycle (IBCOP)
unit, were designed to investigate the treatment of heavily polluted river water. The Daqing River, which is the largest pollutant
contributor to the Dianchi Lake, one of the most eutrophic freshwater lakes in China, was taken for the case study. It was
found that the SBCOP had higher adaptability and better performance in the reduction of COD, TN, and TP, which made it applicable
for the treatment of polluted river water entering the Dianchi Lake. Nitrification rate was observed to be greatly affected
by the influent temperature. During each season, the nitrification in the SBCOP was higher than that in the IBCOP. TN removal
efficiency in the SBCOP was higher than that in the IBCOP during the winter and spring but poorer during the summer, possibly
due to the inhibition of denitrification by higher dissolved oxygen level in the summer. Moreover, symbiotic algaebacteria
growth may be conducive to the removal of pollutants. 相似文献
947.
经济、资源和环境协调发展是当前研究的重要课题。基于生态效率理论,采用因子分析法,以2007年省际数据为样本,测算了各省域经济发展的生态效率值。结果显示:节能减排与水资源利用水平对生态效率的影响较大,我国区域经济发展的生态效率值差异明显,沿着东、中、西部三大经济带空间依次递减,中西部地区的各省域及整体生态效率值均低于全国平均水平。根据以上研究结论提出改善建议,旨在为我国指导经济发展与资源、环境协调可持续发展提供宏观参考。 相似文献
948.
能效对标管理是改善企业经营管理、提高企业竞争力最有效的管理工具之一。介绍了能效对标管理在国内外的应用、存在的障碍及相关对策建议。 相似文献
949.
黑河下游的额济纳绿洲是我国西北地区重要的生态屏障,也是当地人民赖以生存的自然资源,然而由于种种原因,这片绿洲正在衰败并且有消亡的危险.胡杨是典型的潜水旱中生植物,它虽然有较强的耐大气干旱、耐盐碱能力,其生长发育与水分条件的优劣有着十分密切的关系.本文通过研究额济纳天然胡杨的叶水势、蒸腾速率、光合速率的变化规律,综合分析其水分利用效率与叶水势的相关关系,了解胡杨树体内水分运移关系,为揭示胡杨生存现状和合理利用水资源提供理论依据,为合理保护额济纳绿洲胡杨林提供科学支持. 相似文献
950.
XU Fei LUO Zhongyang CAO Wei WANG Peng WEI Bo GAO Xiang FANG Mengxiang CEN Kefa 《环境科学学报(英文版)》2009,21(3):328-332
A process capable of oxidizing NO, SO2 and Hg0 was proposed simultaneously, which utilized a high-voltage and short-duration positive pulsed corona discharge. By focusing on NO, SO2, and Hg0 oxidation efficiencies, the influences of pulse peak voltage, pulse frequency, initial concentration, electrode number, residence time and water vapor addition were investigated. The results indicate that NO, SO2 and Hg0 oxidation efficiencies depend primarily on the radicals (OH, HO2, O) and the active species (O3, H2O2), etc. produced by the pulsed corona discharge. The NO, SO2 and Hg0 oxidation efficiencies improved as increasing pulse peak voltage, pulse frequency, electrode number and residence time, while they are reduced with an increasing initial concentration. By adding water vapor, SO2 oxidation efficiency is improved remarkably, while NO oxidation efficiency is decreased slightly. In our experiments, the simultaneous NO, SO2, and Hg0 oxidation efficiencies reached to 40%, 98% and 55% with the initial concentrations 479 mg/m3, 1040 mg/m3, and 15.0 ug/m3, respectively. 相似文献