Revista: Energy 45-53
Autores: Bartolome Rubio, Carmen; Pallares Ranz, Javier; Herce Fuente, Carlos; Peña Pellicer, Begoña;
Año publicación: 2018
Co-firing coal mine discards with coal in pulverized fuel burners of the current power plants would be a promising way both to reduce the environmental impact of coal production and to energy valorize such residues, with an acceptable economic investment. Changes in fuel blends bring along alterations in flame dynamics and structure which must be considered for successful operation. The paper addresses the challenge of co-firing coal mine waste residues of low rank, high ash content and rich in sulfur with bituminous South African coal in a 500 kWth pulverized fuel pilot plant. The effect of fuel blend composition on combustion performance is investigated by means of image processing and through some relevant operation parameters recordered during the tests. Lower brightness, fluctuations and flicker frequency are registered in the flame videos as coal mine waste residues are added. Nonetheless, the experimental tests confirmed the viability of the process with acceptable levels of carbon monoxide and nitrogen oxides, very stable chamber pressure and gases temperature. The present work also shows the usefulness of visualization systems for detecting and characterizing dynamical instabilities associated with changes in flame structure and certain flame features could be used as inputs in monitoring systems or predictive control.