Radiation heat transfer is the most important heat transfer form between flue gas and lime in lime rotary kiln.Based on the theoretical study of heat exchange of lime, the main factors affecting the radiation capacity of lime rotary kiln are analyzed.On this basis,the key factors to improve the heat exchange capacity of low calorific value gas are studied,and the process system of lime rotary kiln is improved.After analysis and calculation,the radiation heat transfer capacity of the improved process system is greatly improved,which can meet the needs of lime production.