Abstract: In iron ore sintering, the granulation process is the first and an important step. As the fine particles adhere to the coarse coke particles, the NO_x emission generated from coke combustion may be expected to be influenced by that adhering layer. In this study, the granule size distributions and adhering ratios were evaluated by a granulation model. Granulation experiments were also carried out to obtain the granule size distribution and adhering ratio. The influence of the adhering layer on NO_x emissions from the combustion of S type granules was studied by tube furnace experiments. Conclusions include: (1) The adhering ratio predicted from the granulation model can be used as a qualitative index for the evaluation of NO_x emission from coke combustion. (2) The influence of the adhering layer on NO_x emissions was enhanced with increasing adhering layer thickness of S type granules, and the NO_x reduction was enhanced at higher temperatures (around 1373 K), but weakened at lower temperatures (around 1173 K).

铁矿石制粒粘附比预测及其对烧结过程中NO_x生成的影响

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