Optimization of the thermal
substitution rate – Part 2

By means of MI-CFD modeling, improvements to AFR thermal substitution rates (TSR) can be easily validated. Case study II shows, how natural gas can be replaced by alternative fuels.

The first part of the article in issue 5/2012 dealt with the basics and case study I. It was shown, how MI-CFD modelling can be used to understand the thermo-fluid dynamics of a calciner. In Part II a second case study and suggestions for the utilization of AFR are presented.

Case study II

The second case study is selected from a natural gas fired plant operating at 40 % heat input in the kiln burner and 60 % in the calciner. The client wanted to replace natural gas by waste derived fuels, i.e., Solid Recovered Fuel (SRF) and biosolids in both calciner and kiln burners. A brief summary of the...

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