邢奕, 崔永康, 苏伟, 尹丽鲲, 刘应书, 李子宜, 路培. SBA-15脱除超细颗粒的机制研究[J]. 工程科学学报, 2020, 42(3): 313-320. DOI: 10.13374/j.issn2095-9389.2019.04.01.004
引用本文: 邢奕, 崔永康, 苏伟, 尹丽鲲, 刘应书, 李子宜, 路培. SBA-15脱除超细颗粒的机制研究[J]. 工程科学学报, 2020, 42(3): 313-320. DOI: 10.13374/j.issn2095-9389.2019.04.01.004
XING Yi, CUI Yong-kang, SU Wei, YIN Li-kun, LIU Ying-shu, LI Zi-yi, LU Pei. Study of the mechanism of removing ultrafine particles using SBA-15[J]. Chinese Journal of Engineering, 2020, 42(3): 313-320. DOI: 10.13374/j.issn2095-9389.2019.04.01.004
Citation: XING Yi, CUI Yong-kang, SU Wei, YIN Li-kun, LIU Ying-shu, LI Zi-yi, LU Pei. Study of the mechanism of removing ultrafine particles using SBA-15[J]. Chinese Journal of Engineering, 2020, 42(3): 313-320. DOI: 10.13374/j.issn2095-9389.2019.04.01.004

SBA-15脱除超细颗粒的机制研究

Study of the mechanism of removing ultrafine particles using SBA-15

  • 摘要: 利用扫描电迁移率颗粒物粒径谱仪(SMPS),针对不同孔径的介孔材料SBA-15,探索对UFPs(2.5~25 nm)的去除效率及脱除机理,以期为介孔材料过滤脱除UFPs在钢铁工业颗粒物超低排放控制的应用提供理论基础。基于实验结果及表征分析得知:UFPs入孔效应使大孔径介孔过滤介质效率更佳;介孔材料孔径端部内外表面存在大量UFPs亲和位点,提高端部复杂程度有利于提升材料过滤性能;氮气的有无对UFPs去除结果基本没有影响;介孔的存在使UFPs扩散效应更强,颗粒入孔使扩散系数增加,故UFPs在介孔材料实际扩散结果与传统扩散模式理论值(m=−2/3)不同。

     

    Abstract: In 2017, China's industrial dust emissions accounted for 7.96 million tons, of which the iron and steel industry contributed approximately 25%. Particulate matter discharged from the iron and steel industry is mostly of a small size, high in temperature, and complex in composition. The mass concentration of ultrafine particles (UFPs) with particle sizes that are less than 0.1 μm is low; however, the proportion of quantity concentration can be as high as 90%. Currently, the commonly used bag filters and electrostatic precipitators are not sufficiently efficient at collecting fine particles. Additionally, owing to the larger specific surface area of fine dust particles, they easily become carriers of adsorbing harmful gases, which has a greater impact on the environment and human health; thus, it is imperative to determine a simple and efficient filtration method to remove ultrafine particles. In this paper, the removal efficiency and mechanism of UFPs (2.5–25 nm) were investigated by using a scanning electromobility particle size spectrometer (SMPS) test system for SBA-15 for different pore sizes. This was done to provide a theoretical basis for the application of mesoporous materials in the control of ultra-low emission of particulate matter in the iron and steel industry. Based on the experimental results and characterization analysis, it is found that a mesoporous filtration medium with a large pore size is more efficient at affecting UFPs entry. There are many affinity sites for UFPs on the inner and outer surfaces of mesoporous materials with a specific pore size. Increasing the complexity of the ends is beneficial for improve the filtration performance of the materials. The presence or absence of nitrogen has little effect on the removal of UFPs. The diffusion effect of UFPs is stronger owing to the existence of mesoporous particles, and the diffusion coefficient is increased when particles enter the pore. Therefore, there is a difference between the theoretical exponent (m= −2/3) in the traditional model for particle diffusion and the actual diffusion results of UFPs in mesoporous materials.

     

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