Modelling of flow, conbustion, clinker fromation and NOx emissions in long rotary cement kilns

There are several operational problems associated with cement rotary kilns. Frequent problems such as poor product quality, high NOx emissions, and refractory failure have given rise to extensive efforts to investigate and improve their design. Mathematical modelling and CFD simulation constitute effective tools for these purposes. In this work, a CFD-based simulation model for cement kilns was developed with the inclusion of fluid flow, fuel combustion, heat transfer, clinker formation, and NOx emission. With the aid of this tool, an industrial-size cement kiln has been simulated for two typical operations with two different burners. The model results indicate that installment of a new burner technology (low-NOx burner) results in a significant reduction in NOx emissions.