Experiments on the pyrolysis of large beechwood particles in fixed beds

Fixed beds of beechwood particles 10 mm in size were pyrolyzed under conventional pyrolysis conditions. For this purpose, the beds were heated to a maximum temperature of 525 degreesC at rates 3-10 K/min by a flow of hot nitrogen. The loss of mass of the beds in the decomposition process was recorded as a function of time in addition to the temperature field inside the beds, which was measured continuously. The yields of char, tar and gas were quantified, and the composition of the products was analyzed with respect to their elemental composition and calorific values at various temperatures. The results are compared with the findings made in various studies of this topic. The results are an important tool for validating physical and chemical models of heating, drying, and pyrolyzing fixed beds of biomass. (C) 2003 Elsevier B.V. All rights reserved.