In the energy-intensive sector of industrial combustion processes, the energy cost reduction and the minimization of environmental impact for example by reducing the CO2 emission represent major challenges for plant operators. Substituting primary, fossil fuels such as brown or hard coal by so-called alternative fuels such as plastic waste or tire chips is one opportunity to meet these challenges. Multi-fuel burner enable this substitution in adjustable fractions be-tween fossil and alternative fuels. However, a constant stable operation considering high frac-tions of alternative fuels (> 70 percent) is currently hardly to realize due to the fluctuating char-acteristics of alternative fuels. In this paper, the authors address the process monitoring using an infrared camera and the subsequent image analysis, which enables online monitoring of the combustion behavior. Hence, an increased use of fractions of alternative fuel is feasible. The integration into a process optimization software provides the advantage of an increased saving potential while simultaneously ensuring a constant product as well as process quality.