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881.
Reducing greenhouse gas emissions without hampering economic growth is a significant issue for China. Taking into account environmental sustainability principles, this study analysed the energy efficiency of 30 regions of China for the period 2002–2007. By employing a data envelopment analysis (DEA) approach, this study included undesirable CO2 and SO2 outputs and the desirable GDP output in the model. Empirical outcomes demonstrated that the overall average technical efficiency (TE) of China is 0.843, indicating a 15.70% input inefficiency. Among three geographic areas, the east has the highest technical efficiency, with the highest ability to set up clean-burning power plants based on best technology available. Performance in the west is less good because of much inefficient technology. Finally, the study demonstrates detailed management implications of the BCG matrix. The most important contribution of this paper is a detailed demonstration of an energy performance evaluation mechanism for China. The valuable results and insights gained can be equally effectively applied to studies in other developing countries facing the same gaseous emissions.  相似文献   
882.
水力负荷对生物陶粒反应器运行的影响   总被引:3,自引:1,他引:3  
不力负荷较低是影响生物陶粒反应器在实际中运用推广的重要因素之一。本实验研究了不同水力负荷条件下生物陶粒反应器对进水中有机物,氨氮及其它污染物的去除效果。结果表明,不同水力负荷对生物陶粒反应器处理效果没有影响,对OC,氨氮,UV254,色度和浊度去除率分别为20%,90%,30%,38%,76%。  相似文献   
883.
石灰石颗粒移动床脱硫过程影响因素的研究   总被引:1,自引:0,他引:1  
探讨了以石灰石颗粒为脱硫剂、移动床反应器脱除二氧化硫过程的影响因素.结果表明,空床气速和液体喷淋密度是影响脱硫效率的主要因子,其次为二氧化硫浓度和烟气进口温度,而床层下移速度(大于65mm·h-1)对脱硫效率没有明显影响.当液体喷淋密度小于某一临界值时,脱硫效率随液体喷淋密度的增大而增大,但喷淋密度大于临界值后,脱硫效...  相似文献   
884.
Ti/Sb-SnO_2 anodes were prepared by thermal decomposition to examine the influence',of the amount of Sb dopant on the structure and electrocatalytic capability of the electrodes in the oxidation of 4-chlorophenol.The physicochemical properties of the Sb-SnO_2 coating were markedly influenced by different amounts of Sb dopant.The electrodes,which contained 5% Sb dopant in the coating, presented a much more homogenous surface and much smaller mud-cracks,compared with Ti/Sb-SnO_2 electrodes containing 10% or 15% Sb dopant,which exibited larger mud cracks and pores on the surface.However,the main microstructure remained unchanged with the addition of the Sb dopant.No new crystal phase was observed by X-ray diffraction(XRD).The electrochemical oxidation of 4-chlorophenol on the Ti/SnO_2 electrode with 5% Sb dopant was inclined to electrochemical combustion;while for those containing more Sb dopant,intermediate species were accumulated.The electrodes with 5% Sb dopant showed the highest efficiency in the bulk electrolysis of 4-chlorophenol at a current density of 20 mA/cm~2 for 180 min;and the removal rates of 4-chlorophenol and COD were 51.0% and 48.9%,respectively.  相似文献   
885.
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   
886.
Phytoremediation is a valuable technology for mitigating soil contamination in agricultural lands,but phytoremediation without economic revenue is unfeasible for land owners and farmers.The use of crops with high biomass and bioenergy for phytoremediation is a unique strategy to derive supplementary benefits along with remediation activities.Sunflower(Helianthus annuus L.) is a high-biomass crop that can be used for the phytoremediation of polluted lands with additional advantages(biomass and oi...  相似文献   
887.
For wastewater treatment in rural areas, a novel three-stage step-feed wastewater treatment system, combined with a drop-aeration biofilm process, was tested in the laboratory to investigate its performance in removing suspended solids (SS), chemical oxygen demand (COD), NH4+-N, total nitrogen (TN), and total phosphorus (TP). The removal rates of SS, COD and NH4+-N were 90%, 80%, and 90% in efluent concentrations less than 10 mg/L, 50 mg/L and 8 mg/L, respectively. The TP removal rate was less satisfactory....  相似文献   
888.
生物滤池与固定——悬浮填料复合式生物膜反应器脱臭   总被引:10,自引:1,他引:10  
为了探讨生物法处理含H2S恶臭气体的效率及酸积累问题,利用两种生物反应器进行了处理H2S的试验研究.结果表明,生物滤池脱臭效率高,但液相H2SO4积累明显,pH值低.复合式生物膜反应器装有固定一悬浮填料,集生物过滤和生物吸收为一体,当容积负荷Nv≤190gH2S/m3·d时,具有很高的去除能力,液相pH≥6.  相似文献   
889.
聚合硫酸铁处理终端焦化废水的研究   总被引:2,自引:0,他引:2  
确定了聚合硫酸铁处理终端焦化废水的最佳投药量和 p H值 ,讨论了影响其混凝效果的主要因素。实验结果表明 ,处理后出水 COD、浊度的去除率达 80 %以上 ,对酚、氰的去除率可达到 40 %、5 0 %。  相似文献   
890.
热化学脱硫法因铵盐回收率低、产物不稳定,无法解决实用化问题。氧化热化学法应用超强脉冲电场产生高浓度、高能量的活性粒子,使SO2在氧化过程中生成H2SO4,与NH3进行热化学反应,生成稳定的固体微粒(NH42SO4,用电收尘器加以回收。脱除率、回收率可达90%左右,脱除1m3烟气中SO2耗能为4Wh,实现了干法高效脱硫。一次投资大幅度减少,回收铵盐基本上抵消了药品费和电费。  相似文献   
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