Abstract

In the mineral and metal industry, operational enhancement is supported by improved instrumentation devices, complex digital data processing techniques and control algorithms, given by hardware capabilities in control systems. In this sense, optical instrumentation devices present several advantages, such as: non-intrusive monitoring and good spatial and spectral resolution. From the above, the optical devices allow characterizing several processes, such as ladle furnace preheating or steel slab furnace, where the light emitted by the flame, recorded as flame spectrum, is related to the process variability. Information provided by optical devices as spectrometers or cameras, can be relate to the process specific condition, enabling optimization from an energetic, production or pollutants emission point of view. The first contribution of this paper is to summarize optical techniques used for monitoring, control and optimization into industrial combustion based processes. We summarize applications of process diagnosis and optimization, with our testing experiments. The second contribution of this paper is to analyse optical information provided by spectrometers and cameras. This information records different spectral and spatial features from flame spectra, which is post-analysed to compute different optical variables. We compare information provided by these devices and the alternatives of combination for a more accurate process diagnosis and their potentialities in the mining and metal industry.