Crucial factors controlling the formation of halogenated organic compounds during high-temperature combustion proc esse s

高温燃烧过程中控制卤代有机化合物形成的关键因素

基本信息

批准号：
21681008
负责人：
TSUBOUCHI Naoto
金额：
$ 16.56万
依托单位：
Hokkaido University (2011)Tohoku University (2009-2010)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Young Scientists (A)
财政年份：
2009
资助国家：
日本
起止时间：
2009 至 2011
项目状态：
已结题

项目摘要

Six dust samples recovered from bag filters of electric arc furnaces for steelmaking or six fly ashes recovered from electrostatic precipitators in pulverized coal-fired power plants are characterized by use of XRD, SEM-EPMA, XPS and TPD techniques to examine several factors controlling the formation of organic halogen compounds in the steelmaking or coal combustion process, respectively. The dust samples contain 2. 1-6. 4 wt%-dry of carbon element, and some of the C can release CO_2 in the TPD up to 300℃to provide carbon active sites. The number is related closely to hexachlorobenzene(HCB) concentration of each dust. Further, it is suggested that the Zn present in the samples consists of ZnFe_2O_4, ZnO and surface ZnCO_3, and the dust with a larger content of the ZnCO_3 has a higher concentration of HCB. On the other hand, the ashes include 20-130цg/gg-dry and 0. 5-4. 2 wt%-dry of F and C elements, respectively, and these components are enriched at the outermost layer of the ash surface. The F consists of both inorganic and organic functionalities, and the proportion of the latter is as high as 84-93 mol%. The C has different types of surface oxygen species, such as carboxyl, lactone/acid anhydride and phenolic groups, and most of these groups decompose into CO_2 or CO up to 800℃to give carbon active sites. When the amount of the O-functional forms increases, the content of organic CF forms tends to increase almost linearly.

从电弧炉的袋过滤器中回收的六个灰尘样品，或从粉状燃煤发电厂中从静电降水器中回收的六个粉煤灰的特征是使用XRD，SEM-EPMA，XPS，XPS和TPD技术来检查多种因素，以检查控制钢或煤混合物中有机卤素化合物的形成的几种因素。灰尘样品包含2个。1-6。 4 wt％的碳元件和某些C可以在TPD中释放CO_2，最多可提供300℃以提供碳活性位点。该数量与每个灰尘的六氯苯（HCB）浓度密切相关。此外，建议样品中存在的Zn由ZnFe_2O_4，ZnO和Surface Znco_3组成，而Znco_3含量较大的灰尘具有较高浓度的HCB。另一方面，灰烬包括20-130цG/gg-dry和0。5-4。 F和C元素的2 wt％ - 二元，这些成分在灰表面的最外层富集。 F由无机和有机功能组成，后者的比例高达84-93 mol％。 C具有不同类型的表面氧，例如羧基，内酯/酸酐和酚类基团，其中大多数将分解为CO_2或CO，或CO，最多800 co，以提供碳活性位点。当O功能形式的数量增加时，有机CF形式的含量几乎趋于线性增加。