Numerical evaluation of different pulverized coal and solid recovered fuel co-firing modes inside a large-scale cement calciner

Partial substitution of coal by alternative solid fuels, such as waste-derived fuels and biomass, is recognized as an advantageous method for greenhouse gas mitigation. However, due to different fuel properties than that of coal, alternative fuels have a direct impact on the performance of existing pulverized coal fired furnaces. Numerical simulations currently represent a useful approach for studying and controlling the co-firing process. Early comprehensive information, parametric studies and initial conclusions that can be gained from numerical simulations are very important in handling modern combustion units. In this study modelling approach for the combustion of pulverized coal, biomass, plastic, and solid recovered fuel is presented. The purpose of the present study is to evaluate six different pulverized coal and solid recovered fuel co-firing modes inside a cement calciner. The thermal share of the solid recovered fuel in these six simulations varied from 0% to 100%. The results obtained, which include the temperature and species concentrations, provide useful conclusions regarding the maximal allowed coal substitution rate for stable cement calciner operation.