炉前煤低温干馏工艺中的挥发分除尘

In the process of low temperature coal pyrolysis, fine particles carried over by pyrolysis gas have negative effect on the tar capture and quality，which is one of the key points for the process development. Filter screen and granular bed were studied for dust capture in the intermittent experiment of pulverized coal pyrolysis with solid heat carrier. Distribution of fine particle size indicates that the fine dust particle especially less than 100μm takes more than 80% of the dust. Filter screen shows a high efficiency of more than 99.9% in the dust removal tests. The result of granular bed filter combined with filter screen in this process indicates that the granular bed filter reduces the charge of filter screen. The dust removal efficiencies of the two chosen granular bed material, quartz sand and ceramic ring, are more than 90%. Dust removal efficiency increases from 91.3% to 97.3% in three intermittent tests using ceramic ring as the granular bed material. Dust deposition has no influence on the yield of gas, and has a litte influence on the yield of tar because some tar fractions are absorbed by deposited dust. It can be concluded that the combination of a moving granular bed filter with a filter screen can be used in the hot process of cogeneration system for dust collection.