| 论文简介 |
Coal pyrolysis is an important way to realize the clean and efficient utilization of coal in China. However, the problem of dust removal from coal pyrolysis gas has restricted its development. Granular bed filters (GBFs) are among the most promising dust removal technologies because of their convenient and efficient filter material. To meet different dust removal requirements, an optimum filling scheme of the GBF must be determined. In this study, the filtration performance of GBFs with three types of filling schemes, single-layer GBFs with uniformsized particles, single-layer GBFs with mixed-sized particles and double-layer GBFs with two sizes of particles, was tested and compared. The results showed that among the single-layer GBFs, the GBFs with medium-sized particles (1–3 mm) and the GBFs with mixed-sized particles are recommended because of their high efficiency and a low pressure drop. Double-layer GBFs yielded better filtration performances than single-layer GBFs and were suitable in applications with high dust removal requirements. However, the filtration performance of double-layer GBFs was correlated with filter material collocation, which primarily depends on the lower-layer granules. To achieve optimum filtration performance, the lower layer of a double-layer GBF should be filled with particles with sizes less than 1 mm. The optimum ratio of the lower-layer height to the overall height should be approximately 0.2, and the value can rise slightly with increasing upper-layer granular size. These results can be used as a guide for optimally filling GBFs under different requirements to further promote the development of clean coal utilization. |
(创新港)
