共查询到20条相似文献,搜索用时 15 毫秒
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Emission of volatile organic compounds (VOCs) during drying of wood particles for particleboard manufacture, or for production of refined biofuels, is a potential environmental problem. The aim of this work is to study the emissions of VOCs during drying, and the influence on the emissions by different drying parameters. The experiments have mainly been done in a batch fluidized bed dryer, but measurements have also been done in a, pilot scale, continuous fluidized bed dryer. The parameters studied are air flow rate through the bed, air temperature, air dewpoint, and bed height. Since the present trend in biofuels and particle drying is towards very high dewpoints during drying, some measurements have been made at dewpoints up to 95℃, corresponding to a water content of 3.2 kg water per kilogram dry air. The emissions have been measured in two different ways, online during drying with a flame ionization detector and through wood analyses of the terpene content in the wood particles before and after dryi 相似文献
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分析了气质联用技术概况及其在各领域应用,并以天然产物槐花为研究对象,从气质联用仪的应用角度对槐花中挥发油和脂肪酸的成分鉴定进行了定性定量分析。 相似文献
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挥发性有机物(Volatile Organic Compounds,VOCs)是强挥发性有机化学物质的总称,挥发性有机物在常温下,是一种逸散性排放的物质,对空气和环境的污染比较严重,对人体的健康也会产生极大的威胁。挥发性有机物主要来源石油化工产品、汽车尾气、化学溶剂、涂料油漆、废物处理等等,因此对挥发性有机物的污染受到越来越多的人重视。通过利用气相色谱对空气和室内进行测量、分析、研究。 相似文献
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The desalting property of ion-exchange resins in organic solvent is reported by using potassium acetate as a model compound. The experimental results show that the solvability of the solvent, stirring speed, and temperature are the factors which influence the ion-exchange rate. The increase of solvability, stirring speed and temperature will speed up the ion-exchange process. 相似文献
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Indoor air pollution belongs to the factors which puts the health of the corresponding occupants at risk. Effects of ventilation and, hence, various air flow regimes as parameters contributing to reduced air pollution in indoor spaces were further studied. For this purpose, air flow and distribution of the pollutant concentration were three‐dimensionally modeled at various ventilation rates. Results indicate that an increase in input air flow rate into the room in early times directly contributes to enhanced concentration of the pollutant in the indoor space. In general, with increasing the ventilation rate and changing the fluid‐flow regime from laminar to turbulent, the average concentration of the pollutant inside the indoor space decreased significantly. 相似文献
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The new model describing the gaseous transport through graphite gaskets is based on the assumption of a flow in the transition regime through nano‐scale capillaries, using the Maxwellian wall‐slip boundary condition for rarefied gases. Together with an earlier published model describing the liquid transport in graphite gaskets, it enables the characterization of fugitive emissions of volatile organic compounds from fluid‐charged flange joints in chemical and petrochemical plants as a function of medium properties, pipe pressure, and gasket stress. Additionally, combination of the models allows predicting the emission rates of gases by experiments with liquids as the emitting fluid. Finally, recommendations are made to improve the gaskets with respect to their sealing performance towards gases. 相似文献
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利用不锈钢采样罐和全自动预浓缩/GC/MS系统,在58-Ⅱ型和JN43-80型焦炉顶测试了炼焦过程中挥发性有机物(VOCs)中各组分的浓度,结合OH自由基消耗速率分析了这些物质的反应活性。研究发现,装煤时刻产生的TVOCs浓度明显高于炼焦过程产生的;炼焦过程中(包括装煤时刻)无组织排放的VOCs反应活性各不相同。 相似文献
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报道了力合科技湖南股份有限公司研发的一种吹扫捕集-气相色谱仪针对地表水中挥发性有机物中8种苯系物进行自动在线分析的研究。仪器集自动进样、吹扫捕集浓缩、气相色谱分离检测功能于一体,水中有机污染物经过吹扫捕集浓缩后再进入气相色谱仪进行分离检测。该仪器实现了地表水中挥发性有机物自动在线分析,并在此基础上建立了一种地表水中8种苯系物进行同时测定的在线分析方法。实验结果在2~200μg/m L范围内线性良好,线性相关系数均大于0.999,检出限在0.14~0.39μg/m L范围内。仪器性能稳定可靠,方法的前处理简单快速,重复性较好,适用于地表水中挥发性有机物的测定。 相似文献
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本文系统研究了水热法制备的铁掺杂纳米Ti O2和氮掺杂纳米Ti O2在可见光照射下对挥发性有机物(volatile organic compounds,VOCs)的降解能力和降解产物.铁掺杂纳米Ti O2和氮掺杂Ti O2对光的吸收边分别红移到540 nm和580 nm;在可见光下具有良好的催化活性,24 h内对挥发性有机物的降解率达20%—50%,降解后的最终产物可能主要为CO2. 相似文献
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Khurram Aftab Jasdeep Mandur Hector Budman Neal W. Currier Aleksey Yezerets William S. Epling 《Catalysis Letters》2008,120(3-4):229-235
Palladium catalysts supported on CeO2, Ce0.75Zr0.25O2, ZrO2, TiO2, Nb2O5, Al2O3 were studied on the total oxidation of butyl carbitol. Several techniques were used to characterize the samples such as diffuse
reflectance spectroscopy (DRS), temperature programmed reduction (TPR), cyclohexane dehydrogenation and CO temperature programmed
desorption (TPD). DRS and TPR results revealed the presence of bulk PdO and PdO with strong interaction with the support.
The catalytic tests showed the following order for decreasing activity: Pd/Ce0.75Zr0.25O2 > Pd/CeO2 > Pd/TiO2 > Pd/Nb2O5 > Pd/Al2O3 > Pd/ZrO2. However, when the turnover frequency (TOF) was calculated, all the samples had similar values. 相似文献
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活性炭纤维布吸附与电热脱附挥发性有机化合物研究进展(英文) 总被引:2,自引:0,他引:2
Pierre Le Cloirec 《中国化学工程学报》2012,20(3):461-468
A general research program,focusing on activated carbon fiber cloths(ACFC) and felt for environmental protection was performed.The objectives were multiple:(i) a better understanding of the adsorption mechanisms of these kinds of materials;(ii) the specification and optimization of new processes using these adsorbents;(iii) the modeling of the adsorption of organic pollutants using both the usual and original approaches;(iv) applications of ACFC in industrial processes.The general question was:how can activated carbon fiber cloths and felts be used in air treatment processes for the protection of environment.In order to provide an answer,different approaches were adopted.The materials(ACFC) were characterized in terms of macro structure and internal porosity.Specific studies were performed to get the air flow pattern through the fabrics.Head loss data were generated and modeled as a function of air velocity.The performances of ACF to remove volatile organic compounds(VOCs) were approached with the adsorption isotherms and breakthrough curves in various operating conditions.Regeneration by Joule effect shows a homogenous heating of adsorber modules with rolled or pleated layers.Examples of industrial developments were presented showing an interesting technology for the removal of VOCs,such as dichloromethane,benzene,isopropyl alcohol and toluene,alone or in a complex mixture. 相似文献
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