Effective diffusivity of oxygen in the ash layer of Huadian oil shale semicoke
Received date: 18 Oct 2019
Accepted date: 15 Jan 2020
Published date: 15 Jun 2021
Copyright
Diffusion of oxygen in the ash layer usually dominated the combustion of oil shale semicoke particles due to the high ash content. Thus, effective diffusivity of oxygen in the ash layer was a crucial parameter worthy of careful investigation. In this paper, the effective diffusivity of oxygen in the ash layer of Huadian oil shale semicoke was measured directly using an improved Wicke-Kallenbach diffusion apparatus. The experimental results showed that higher temperature would lead to a higher effective diffusivity and a thicker ash layer had the negative effect. Especially, the effective diffusivity along the direction perpendicular to bedding planes was much lower than that along the direction parallel to bedding planes. In addition, an effective diffusivity model was developed, which could be used to describe the mass transfer of oxygen in the ash layer of oil shale semicoke.
Key words: oil shale semicoke; diffusivity; pore structure; ash layer
Yiqun HUANG , Yiran LI , Man ZHANG , Boyu DENG , Hao KONG , Junfeng WANG , Junfu LYU , Hairui YANG , Lingmei WANG . Effective diffusivity of oxygen in the ash layer of Huadian oil shale semicoke[J]. Frontiers in Energy, 2021 , 15(2) : 320 -327 . DOI: 10.1007/s11708-020-0674-3
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