Drying pretreatment plays an important role in using oil shale. Microwave drying is a rapid

efficient and energy-saving method for drying. An experimental system for microwave drying is set up by remolding the household microwave oven and the influence of microwave power on drying of the Liushuhe oil shale is investigated. The dynamics of microwave drying is analyzed with single diffusion models and 13 thin layers dry models. The result show that the time required for microwave drying is much shorter than that of traditional drying and the rate of microwave drying is much higher. The semi-empirical model of double diffusion is applicable to the microwave drying of oil shale. The microwave drying of oil shale is a double diffusion controlled process by moisture (liquid or vapor). The energy consumption power with 300

400 and 550 W is similar. To reach the same drying effect with less energy

the power of 550 W is more appropriate for Liushuhe oil shale.