Effect of Different Configurations on Small Pellet Combustion Systems

The combustion of pellets in small stoves is a complex issue in which many factors must be considered. The University of Vigo has developed a 24 kWt fixed bed stove pilot plant for studying pellet combustion in which different configurations and operational conditions can be tested. An extensive experimental study using the statistical analysis approach is presented. Analyses of the main control factors involved in the performance of stoves of this kind and their optimization are also presented, including preheating of air, secondary air supply and gas recirculation. The influence of air and pellet feeding rates and stove temperature as part of a group of energy and environmental variables is analyzed in detail. The study establishes that the use of secondary air and, especially, the recirculation of gases considerably reduce CO emissions.