The rotary kiln is widely used for the thermal treatment of granular materials in various industries. A better understanding of the heat transfer phenomena, both inside and outside of the industrial rotary kiln, will lead to developing sustainable production techniques, such as materials recycling and heat waste recovery. The present paper summarises two complementary works based on infrared measurements. The first, by Le Guen et al. [5], was conducted at the industrial scale and sought to correlate the external wall temperature with the thermal behaviour of rotary kilns. The second, by Huchet et al. [17], was performed at the pilot scale in order to derive the external heat transfer coefficient into heat waste recovery. A combination of these two approaches, based on a physical model of the full system at a large scale, is provided while the inherent energy efficiencies are calculated from the logarithmic mean temperature difference.

回转窑在各种行业中广泛用于颗粒材料的热处理。更好地理解工业回转窑内部和外部的传热现象，将导致开发可持续的生产技术，例如材料回收和废热回收。本文总结了基于红外测量的两个互补工作。第一个，由Le Guen等人撰写。[5]是在工业规模上进行的，旨在将外壁温度与回转窑的热行为相关联。第二，Huchet等人。[17]在中试规模下进行，目的是将外部传热系数推导到废热回收中。基于整个系统的大规模物理模型，提供了这两种方法的组合，同时根据对数平均温度差计算出固有的能量效率。