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KBr和KI改性黏土脱除模拟烟气中的单质汞  [PDF]
沈伯雄,蔡记,陈建宏,李卓,何川
化工学报 , 2014, DOI: 10.3969/j.issn.0438-1157.2014.02.048
Abstract: 黏土是一种非常廉价的天然矿物,为了考察溴和碘改性黏土(膨润土)脱除烟气中单质汞的特性,采用浸渍法分别制备了KBr和KI改性黏土(KBr-clay和KI-clay)。在固定床吸附实验台上进行了脱除Hg0的实验研究,考察不同的负载量、吸附温度以及烟气中SO2和水蒸气等对KI-clay和KBr-clay脱除单质汞的影响。研究结果表明:改性后黏土的比表面积、孔隙结构未发生显著的改变,表面官能团也没有发生本质的变化。KI-clay和KBr-clay脱汞能力大大提高,在同等实验条件下,KI-clay脱汞性能优于KBr-clay。研究表明单质汞在改性黏土表面产生了化学吸附,烟气中低浓度SO2的存在对汞脱除有一定的促进作用,在相同的实验条件下,SO2对KBr-clay促进作用更加明显,但水蒸气在低温下对脱汞具有很强的抑制作用,提高吸附温度可以消弱水蒸气的负面影响。
低温等离子体强化燃煤烟气Hg0氧化的气氛影响及特性分析
Influence of gas composition and characteristic analysis on oxidation of Hg0 in coal-fired flue gas by non-thermal plasma
 [PDF]

张君,段钰锋,赵蔚欣,朱纯,周强,佘敏
- , 2016, DOI: 10.3969/j.issn.1001-0505.2016.02.012
Abstract: 为了研究燃煤烟气成分对低温等离子体氧化元素汞的影响,以石英玻璃管为阻挡介质,内插不锈钢棒为高压放电极, 利用交流高压放电产生低温等离子体强化模拟烟气中Hg0氧化.研究输入能量和烟气成分对模拟烟气中Hg0形态转化与协同脱硫脱硝的影响规律.结果表明,初始时Hg0氧化率随输入能量增大而提高,原因是模拟烟气中O2分解产生的O自由基数目增多,但输入能量过大会促使模拟烟气中N2分解,生成NO并消耗O自由基,导致Hg0氧化率下降.烟气中O2和CO2含量增大,分解产生的自由基O数量增多,有利于Hg0氧化反应.低温等离子可将NO和SO2分解成N2和S,同时产生能够促进Hg0氧化的O自由基,因此低温等离子促进NO和SO2氧化Hg0的同时可实现脱硫脱硝的目的.
To study the effect of coal-fired flue gas composition on the oxidation of Hg0 by using non-thermal plasma, the quartz glass tube and the stainless steel rode were used as the barrier medium and the high voltage discharge electrode, respectively, and the Hg0 in simulated flue gas was oxidized by alternative current high voltage discharge non-thermal plasma. The effects of input energy and gas composition on the mercury speciation transformation and the simultaneous desulfurization and denitration in simulated flue gas were investigated. The results show that the oxidation efficiency of Hg0 increases with the increase of the input energy in the initial stage. The reason is that the contents of free radical O increases by O2 decomposition, but N2 in simulated flue gas decomposes when the input energy is large enough, which consumes free radical O and produces NO, leading to the decrease of elemental mercury oxidation efficiency. The content of free radical O increases with the increase of the contents of O2 and CO2 in simulated flue gas, which can promote Hg0 oxidation. NO and SO2 can be decomposed into N2 and S by non-thermal plasma, and free radical O which can oxidize Hg0 is simultaneously produced. Therefore, non-thermal plasma can promote NO and SO2 to react with Hg0 and realize desulfurization and denitration
Simultaneous oxidation of NO, SO2 and Hg0 from flue gas by pulsed corona discharge

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,
Abstract: 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.
The Experimental Study to Hg0 Adsorption of Fly Ash in Flue Gas
燃煤飞灰对锅炉烟道气中Hg0的吸附特性

Wang Ligang,Peng Suping,Chen Changhe,
王立刚
,彭苏萍,陈昌和

环境科学 , 2003,
Abstract: Through the simulation experimentation, the Hg adsorption characteristics of fly ash in flue gas were studied carefully in laboratory. From the experiment results it was found that Hg adsorption capacity of different porous medium in fly ash was different obviously. Unburned carbon had higher Hg adsorption capacity. The surface-area of BET sorbent had positive correlation with Hg adsorption capacity. Hg concentration in blend gas had non-linearity relationship with Hg adsorption capacity. Hg adsorption capacity of 5×10-7 Hg concentration was only 1/2 compared to that of 5×10-6. Adsorption temperature had negative correlation with it. CO in unburnt carbon surface was beneficial to oxidation and chemic adsorption of Hg. It was obtained that the porous structure and huge surface-area of the unburned carbon was benefit to the Hg adsorption in flue gas.
Removal of NO and Hg0 in Flue Gas Using Alkaline Absorption Enhanced by Non-thermal Plasma
非热等离子体强化碱液吸收脱除烟气中NO和Hg0的研究

LUO Hong-jing,ZHU Tian-le,WANG Mei-yan,
罗宏晶
,朱天乐,王美艳

环境科学 , 2010,
Abstract: 采用正电晕放电产生非热等离子体将模拟烟气中的NO和Hg0氧化成更易吸收的NO2和Hg2+,从而强化其碱液吸收脱除,并考察放电电压及入口SO2和NO浓度对氧化和脱除效果的影响.结果表明,随着电压升高,NO和Hg0的氧化和脱除量增加.当NO浓度为134 mg/m3,放电电压为12.8kV时,吸收塔出口NO和NO2浓度分别为0和69 mg/m3.当Hg0浓度为110 μg/m3,放电电压为13.1 kV时,吸收塔出口Hg0和Hg2+浓度分别为22 μg/m3和11 μg/m3.SO2对Hg0的氧化和脱除具有一定促进效应,且这种效应随SO2浓度提高而增强,但SO2对NO的氧化和脱除影响不大.NO对Hg0氧化有明显的抑制效应,随着NO浓度提高,Hg0氧化和脱除量显著降低.当800 mg/m3 SO2、 134 mg/m3 NO和110 μg/m3 Hg0共存时,对应77 J/L的能量输入,NO和Hg0的脱除率分别为57%和31%.
Hg0 removal by an activated coke-supported MnO2 catalyst
活性焦负载MnO2对气态Hg0的吸附脱除研究

WANG Junwei,LIU Ruiqing,
王钧伟
,刘瑞卿

环境科学学报 , 2012,
Abstract: Gas-phase Hg0 removal by an activated coke(AC) and an activated coke-supported MnO2 catalyst(MnO2/AC) were studied.The influences of MnO2 loading,temperature,inlet Hg0 concentration and flue gas components on Hg0 removal were characterized.It was found that MnO2/AC had a much higher Hg0 removal capability than AC,which can be attributed to the oxidation activity of MnO2.The capability increased with an increase of MnO2 loading in the range of 1%~10%,and it was promoted by O2 and HCl but inhibited by SO2 and H2O.In the stack temperature range(120~200 ℃),MnO2/AC showed high activity for Hg0 removal.Scanning electron microscope-energy dispersive X-ray analysis(SEM-EDX) and sequential chemical extraction experiments confirmed that Hg0 can be oxidized by MnO2 to form HgO and subsequently adsorbed on AC,leading to the high capability of MnO2/AC for Hg0 removal.
Removal of elemental mercury from coal combustion flue gas by bentonite-chitosan and their modifier
膨润土-壳聚糖及其改性吸附剂脱除燃烧烟气中Hg0的性能研究

ZHANG An-chao,SUN Lu-shi,XIANG Jun,HU Song,FU Peng,SU Sheng,ZHOU Ying-biao,
张安超
,孙路石,向军,胡松,付鹏,苏胜,周英彪

燃料化学学报 , 2009,
Abstract: Adsorption experiments of vapor-phase elemental mercury were carried out by using modified bentonite-chitosan in a laboratory-scale fixed-bed reactor.VM3000 online mercury analyzer was applied to detect the inlet and outlet mercury(Hg0) concentrations.The characterizations of the sorbents were analyzed using the method of nitrogen(N2) adsorption/desorption,scanning electron microscope(SEM) and Fourier transform infra-red spectroscopy(FT-IR),etc..It was observed that the porosity and specific surface area de...
Effect of KBr on the micellar properties of CTAB
Weican Zhang,Ganzuo Li,Jianhai Mu,Qiang Shen,Liqiang Zheng,Haojun Liang,Chi Wu
Chinese Science Bulletin , 2000, DOI: 10.1007/BF02886293
Abstract: The effect of KBr on the size, shape and microviscosity of CTAB micelles has been investigated by means of laser light scattering (LLS),1H NMR measurements and fluorescence probe. The data obtained from the various techniques are quantitatively in agreement. The Rh of micelles in 0.01 rnol · L 1 CTAB solution increases from 3.5 nm to 43 nm andR g increases to 89 nm with addition of KBr salt. In this process, both the microviscosity and molecular weight of micelles Mw have noticeable increases, too. The rod-like micelles are formed at 0.1 rnol · L1 KBr and the worm-like micelles are formed at above 0.2 rnol · L-1 KBr.
KI改性黏土脱除烟气中单质汞的研究  [PDF]
沈伯雄,陈建宏,蔡记,何川,李卓
环境科学 , 2014,
Abstract: 卤素改性材料对烟气中单质汞的去除具有较高的效率,黏土(膨润土)在我国分布广,资源丰富且廉价易得.为探究KI改性黏土对烟气中单质汞的脱除效率,以浸渍法制得了KI改性膨润土,研究了不同KI负载量、不同吸附温度及不同烟气氛围下,改性膨润土对Hg0的脱除效率和累积吸附量,并与原始膨润土进行对比.运用比表面分析(BET)、傅里叶红外光谱仪(FTIR)及热重分析法(TGA)等方法对材料的物理化学特性进行了分析.结果表明,KI改性大大提升膨润土对Hg0的脱除效率,并且Hg0的脱除效率随着KI负载量的加大而上升.温度提高了吸附剂吸附Hg0的性质,吸附剂主要表现为化学吸附.O2有利于吸附剂对Hg0的吸附.SO2对吸附剂吸附Hg0有轻微的促进作用,H2O的存在对吸附剂吸附Hg0具有很强的抑制作用.
Hg0 trends in the North and South Atlantic  [cached]
Soerensen A. L.,Jacob D. J.,Streets D.,Witt M.
E3S Web of Conferences , 2013, DOI: 10.1051/e3sconf/20130107002
Abstract: It was recently found that atmospheric Hg had decreased with 20-38% worldwide since the mid 1990s. However, the decrease is not supported by emission inventories that show rising global anthropogenic emissions over the past decades. We analyzed atmospheric data from 22 ship cruises in the North Atlantic (defined as 2°N-65°N), and 15 in the South Atlantic (defined as 70°S-8°N) between 1977 and 2010, as well as surface water Hg0 from 10 cruises in the West Atlantic Ocean between 1998 and 2010. Linear regression analysis based on these cruise ensembles for each hemisphere will be discussed. We use the GEOS-Chem biogeochemical model to explore possible drivers of the Hg0 trends found in this study and at previous studies at land based stations. These findings will also be discussed.
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