Study of the influence of the composition of several biomass pellets on the drying process

In this work, theorical and experimental research in the field of the drying has been made. For this purpose, the exhaust gases and hot air generated from the exchange body of a 6.7 kW boiler for domestic heating were used for a biomass drying process. The fuels used were different densified biomass materials: pine, peartree and coniferous (Pinus pinaster, Pynus communis and mixing of Pyrus sylvestris, respectively). The pellets were characterised by means of the lower heating value, proximate and ultimate analyses. The combustion parameters (CO(2), CO, NO, NO(2) and NO(x) contents, fumes temperature and the moisture content in biomass) were analysed in order to detemine what fuel was more suitable for the drying process of common reed (Arundo donax. L). The influence of the residue type and fuel mass flow on the combustion parameters have been studied. Finally, a global energy balance of the drying process and obtained losses have been evaluated, as well as the coefficients and the global yield of the process drying for common reed. From the results obtained, it was infered that the coniferous residue was the material presenting the most interesting yield of combustion and drying yield (80.2 and 47.5% respectively). (C) 2011 Elsevier Ltd. All rights reserved.