CO-FIRING OF LOW RANK COAL AND BIOMASS: A PROMISING PILOT EXPERIENCE

Abstract: This paper presents a co-firing experience, with coal and biomass, whose objective was to prove the technical, environmental and economical feasibility (although the paper does not deal with this last one) of the implantation of this technology in a power plant of pulverised low rank coal. Precisely, this kind of coal particularities, specially its low energy density (kJ/m3), with similar values to most of the different dry biomass resources, is what makes a difference between this project and other co-firing experiences carried out previously. With regard to the main results, it must be pointed out that when introducing in the boiler a 5 % of biomass: No operation problem arose and no noticeable reduction in the boiler efficiency was caused. Apart from the expected reductions in CO2 and SO2, an important decrease in NOx emissions was detected. No emissions increase of CO, particles and volatile compounds were detected. Another aspect dealt in the project was the study of the possible impacts of forest biomass harvesting on the sustainability of the forest