Fine particle emissions from military deactivation furnaces are a concern due to the enrichment of heavy metal species. These species are typically in the submicrometer sizes and difficult to capture in conventional particle control devices. To overcome the emissions problems, nanostructured sorbents have been developed. This paper will describe results of studies in both laboratory scale incinerators and full scale systems about a novel nanostructured sorbent process for capture of heavy metal species in combustion exhausts, and formation of a complex that binds the heavy metal species. The paper will describe results of studies. The precursor of in-situ generated silica and titania impregnated pillar intercalated clay were introduced at various feed rates with the incinerator flue gas stream into a tube furnace heated at 1000 °C. The particle size distribution profiles of the effluent gas stream were characterized by a scanning mobility particle sizer and an electrical low pressure impactor. Particulate phase samples of the effluent were collected by a cascade impactor with a cutoff diameter of 1 urn. The mobility of captured lead and cadmium species were studied by leachability test using ICP-MS. Injecting both of these two sorbents successfully decreased the concentration of particles less than 30 nm in the effluent gas stream. At the similar mass feed rate, comparing to Ti-PILC, the in-situ generated silica was found to be more effective in the capture of fine particles up to 100 nm.
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