Microwave irradiation (MI) is a new method to enhance desorption of shale gas. It is very important to explore the desorption law and influencing factors of shale samples under MI to improve energy utilization efficiency and optimize microwave stimulation effect. The gas desorption properties of shale sample under different MI time (off-line group) and power (on-line group) conditions were discussed by using an independently developed microwave treatment device. At the same time, the dynamics law of shale desorption was studied by using the traditional desorption model and the dynamics desorption model, which revealed the mechanism of shale desorption enhanced by MI. The experimental results show that MI can significantly improve the desorption rate of shale and the diffusivity of adsorbed gas. The shale temperature finally reached 580.15K at microwave power 1800W, and the desorption amount in the MI stage is about 2.5 times than that of the natural desorption stage. Under MI, the diffusion rate of shale at desorption equilibrium is above 0.8, and increases gradually with the microwave power. The constant diffusion coefficient D_w and initial diffusion coefficient D_w0 have a threshold effect with the change of microwave power. Only when the microwave power is greater than 1200W, the shale diffusion coefficient and the gas desorption rate would increase rapidly. The permeability model has a better fitting adaptability on MI desorption stage, followed by the empirical model and the diffusion model. The C-D model has a poor fitting suitability on the natural desorption stage. In comparison, the D-D-C model has the best fitting effect for the whole shale desorption curve, especially for the later stage. In general, D-D-C model and permeability model have better fitting effect than other models.

微波辐射（MI）是一种增强页岩气解吸的新方法。探索MI下页岩样品的解吸规律及影响因素对提高能量利用效率、优化微波增产效果具有重要意义。利用自主研制的微波处理装置，讨论了不同MI时间（离线组）和功率（在线组）条件下页岩样品的气体解吸特性。同时，利用传统解吸模型和动力学解吸模型研究了页岩解吸动力学规律，揭示了MI增强页岩解吸机理。实验结果表明，MI可以显着提高页岩的解吸率和吸附气的扩散率。页岩温度最终达到了 580 度。15K微波功率1800W，MI阶段解吸量约为自然解吸阶段的2.5倍。在 MI 下，解吸平衡时页岩的扩散速率在 0.8 以上，并随着微波功率的增加而逐渐增加。恒定扩散系数 D_w和初始扩散系数 D _w0随着微波功率的变化具有阈值效应。只有当微波功率大于1200W时，页岩扩散系数和气体解吸速率才会迅速增加。渗透率模型对MI解吸阶段的拟合适应性较好，其次是经验模型和扩散模型。CD 模型在自然解吸阶段的拟合适应性较差。相比之下，DDC模型对整个页岩解吸曲线拟合效果最好，尤其是后期。一般来说，DDC 模型和渗透率模型比其他模型具有更好的拟合效果。