Study on the anisotropy of mass transfer for oxygen in the ash layer of extremely low calorific oil shale semi-coke

摘要: Abstract Oil shale semi-coke produced from the oil retorting process causes great hazards to environment due its high phenol and polycyclic aromatic hydrocarbons content. A good solution of current is burn it as feedstock. In present work, anisotropy mass transfer for oxygen in ash layer extremely low calorific that featured laminated structure was investigated by using one-dimensional unreacted model unchanging size. Results indicated severe confirmed, diffusion rate along direction perpendicular bedding plane much slower than parallel plane. This difference attributed different porous characters directions. When burning temperature 900 °C, average diffusivities were 0.25 × 10−6 m2/s 2.36 × 10−6 m2/s, respectively, planes. Furthermore, an shrinking sphere size established describe combustion semi-coke, could be concluded resistance major control factor during relative monotonously increased.