Optimization of the
thermal substitution rate – Part 1

By means of MI-CFD modeling, improvements to AFR thermal substitution rates (TSR) can be easily validated. Two case studies are presented where coal and natural gas were replaced with petcoke and AFR (SRF and BS).


In a drive to reduce production costs and improve the environment, the cement industry is using more and more inexpensive fuels and raw materials, such as AFR and petcoke. Some successful examples show thermal substitution rate (TSR) as high as 90 % for AFR and 100 % for petcoke with up to 7 % sulphur content. A quick fix in the absence of well-structured strategy, either a lower TSR is achieved or plant would suffer from loss in output and/or increase in emissions, unless a step by step approach is carried out with the help of detailed process knowledge and experience. Cinar has...

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