Watershed Transformation Based Identification of the Combustion Region in an Oxy-coal Flame Image

To meet the increasingly stringent standards on pollutant emissions, oxy-coal combustion technologies are being proposed for both existing and new coal-fired power plants. However, there is lack of research to characterize this new type of combustion flame due to the complicity of its structure and background noise. This paper presents a new computer algorithm to identify the combustion region in oxy-coal flame images through the combination of image enhancement, wavelet denoising, and watershed transformation. The algorithm overcomes the limitations of the thresholding method which often wrongly detects the bright background and ignores the dark combustion region. Results on oxy-coal flame images obtained on an oxy-coal combustion test facility are reported to demonstrate the effectiveness of the algorithm proposed.