研究了非薄层状态下昭通褐煤粒径对其干燥及干燥褐煤自燃、复吸特性的影响。采用褐煤非薄层干燥实验装置，测定了不同粒度褐煤非薄层干燥残留水分含量变化，实验结果表明粒度较小的样品具有较高的干燥速率，当褐煤粒度降低至临界粒度(2~5mm)时，进一步降低粒度不会促进褐煤干燥速率的提升；非薄层干燥过程中仅观察到了升速干燥阶段和降速干燥阶段，且最大干燥速率显著低于褐煤薄层干燥研究中的最大干燥速率；褐煤非薄层干燥中样品温度、残留水分为非均匀分布，通过数值模拟发现样品表层和中心区域温度、残留水分存在显著的梯度，温度、残留水分分布呈现分层现象，温度分布数值模拟结果在褐煤非薄层干燥中试实验中得到验证。采用交叉点温度法与绝热氧化速率法测定了干燥后褐煤的自燃特性，在交叉点温度测试过程中自然对流主导热质传递，小于临界粒度时进一步减小褐煤粒度其交叉点温度无明显变化；在绝热氧化速率测试过程中强制对流主导热质传递，绝热氧化速率随褐煤粒度减小持续降低。干燥后褐煤非薄层复吸时，粒度较小的样品具有较高的复吸速率，当褐煤粒度降低至临界粒度时，进一步降低粒度不会导致复吸速率的增加。非薄层状态下褐煤干燥及干燥褐煤自燃与复吸特性均与薄层状态下有显著差异，临界粒度对于褐煤干燥具有重要意义，在临界粒度范围进行干燥可在保证干燥速率的同时降低破碎成 本，且不会导致自燃倾向性与复吸速率提升。

Effects of particle size on lignite drying and spontaneous combustion and resorption characteristics of dried lignite under non⁃thin layer processes were studied. The residual moisture content variation of lignite with different particle sizes was measured by the lignite non⁃thin layer drying experimental device. The results showed that the drying rate of sample with smaller particle size was higher. But the further reduction of particle size under the critical particle size (2-5 mm) did not promote an increase in drying rate. During the non⁃thin layer drying process，only the in⁃ creased⁃rate drying stage and the reduced⁃rate drying stage were observed，and the maximum drying rate was signifi⁃ cantly lower than that in the thin⁃layer drying. The distribution of temperature and residual moisture content in sample was not uniform during the drying process. Through numerical simulation，it was found that there was a significant gra⁃ dient in the temperature and residual moisture content distribution between the surface and central of the sample. The temperature and residual moisture content of sample present a layered distribution. The numerical simulation of temperature distribution was verified in the pilot⁃scale experiment of lignite non⁃thin layer drying. The spontane⁃ ous combustion characteristics of dried lignite were determined by cross⁃point temperature method and adiabatic oxida⁃ tion rate method. During the crossing point temperature test，the natural convection dominates the heat and mass trans⁃ fer. The crossing point temperature was not changed obviously， when the further reduction of the particle size under the critical particle size. During the adiabatic oxidation rate test，the forced convection dominates the heat and mass transfer. The adiabatic oxidation rate decreased continuously with the reduction of lignite particle size. Under the non⁃thin layer status，the resorption of dried lignite with smaller particle size was faster. But the further re⁃ duction of particle size under the critical particle size did not accelerate the resorption process. There are signifi⁃ cant differences in the characteristics of the lignite drying and the spontaneous combustion and resorption characteris⁃ tics of dried lignite between non⁃thin layer statue and thin layer status. The critical particle size is important for lig⁃ nite non⁃thin layer drying. The drying process with lignite in the critical particle size range could reduce the crush⁃ ing cost while ensuring the drying rate，and would not lead to the increase of spontaneous combustion tendency and re⁃ sorption rate.