In this paper, the effect of fluidized bed temperature on primary fragmentation of Huadian oil shale was investigated experimentally in thermal state using a small-scale fluidized bed with N2 as fluidizing gas. The fluidized-bed temperatures changed from 600 °C to 1000 °C. Experimental results indicate that the fluidized bed temperature is an important factor of primary fragmentation of oil shale, and that higher bed temperature results in severer fragmentation. The laminated structure and high ash content may contribute to the primary fragmentation characteristics of Huadian oil shale. The thermal stress fragmentation and devolatilization-induced fragmentation have little effect on small oil shale particles. Furthermore, the experimental data were treated by a neural network method, and a Back Propagation network model for primary fragmentation of oil shale was set up through network learning and validated by experimental data.
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