【摘要】 为实现农牧地区生物质颗粒燃料的高效清洁利用，须充分理解粒径对其燃烧过程的影响。文章通过自主设计的聚光光热颗粒燃烧实验系统，研究了粒径对牛粪颗粒燃烧特性和烟气排放特性的影响。研究结果表明：随着粒径的增加，挥发分释放延迟，着火、燃尽温度及对应时间均增加；粒径增加导致颗粒表面着火温度高于内部，而燃尽温度则相反，同时颗粒内、外燃烧过程分离程度增加，使焦炭燃烧阶段的颗粒内部温度上升；粒径的增加增大了颗粒内部的轴向热阻，导致颗粒表面与内部的着火温度和燃尽温度差异增大；随着粒径的增加，CO与NO体积分数的峰值出现时间与峰值强度均上升，但CO与NO的排放总量并不随着颗粒质量的增加而同比例增加，粒径的增加可抑制CO的排放，并提高NO的排放量与燃料氮的转化率。更多还原

【Abstract】 To realize the efficient and clean utilization of biomass particle fuels in agricultural and pastoral areas, it is necessary to fully understand the effect of particle size on its combustion process. Through the self-designed concentrating photothermal particle combustion experimental system, we explored the impact of different sizes on cattle manure particles’ combustion and gas emission characteristics. The results show that the release of volatile is delayed and the ignition and burnout temperatures and corresponding times increase with increasing particle size. In addition, with increasing of particle size, the surface ignition temperature of the particles was higher than that of the interior. The degree of separation between the internal and external combustion processes of the particles increased, resulting in an increase in the internal temperature of the particles during the char combustion stage. The increase in particle size increases the axial thermal resistance inside the particles, leading to a rise in the difference between the particles’ surface and internal ignition and burnout temperatures. As particle size increases, the peak time and intensity of CO and NO emissions rise, but the total amount of CO and NO produced does not grow in the same proportion as the particle mass, and an increase in particle size results in the suppression of CO emissions and an increase in NO emissions and the conversion rate of fuel-N.更多还原