Oil shale is an important unconventional energy and has enormous reserves in the world. However, the high moisture content reduces the efficiency of oil production in the pyrolysis process. In this paper, experimental and numerical studies were conducted on the drying performance of single Liu Shu River oil shale particles in superheated steam. A 3-D model was developed to simulate the heat and mass transfer process inside the particle, taking into account its property of anisotropy transfer. Generally, it is concluded that the moisture removal rate increases as the steam temperature increases, while increasing the particle size decreases the moisture removal rate. In the whole drying process, the decreasing drying rate period was longer than the constant drying rate period. The anisotropy had an influence on moisture transfer rather than heat transfer process. The moisture content profiles and temperature fields inside the particle were determined at selected times. Several experiments were carried out under the conditions of different temperatures (463–483 K) and particle sizes (5–9 mm). It was found that the developed model predictions agreed well with the experimental data. It is significant to get the microscopic parameters for the investigation of oil shale drying in superheated steam fluidized bed.
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