Evaluation of utilization of corn stalks for energy and carbon material production by using rapid pyrolysis at high temperature

Pyrolysis of agricultural residues (corn stalks) took place batch wise in a laboratory captive sample reactor (wire mesh) at atmospheric pressure. The process was studied by varying the temperature (470-710 degrees C) with an average heating rate of 60 degrees C s(-1) and a reaction time of 0.2 s. The carrier gas used for both pyrolysis and GC analysis was He. The nature and quantity of gases produced and the main characteristics of the charcoals formed have been determined. From the GC analysis, CO showed the higher yield, followed by H-2, CH4 and M. The increase in temperature is especially important to increase the production of gas, mainly hydrogen. From gas composition and proximate analysis, the heating value of gas and solid phases has been determined. A kinetic model of pyrolysis based on first order kinetics and on total devolatilization has been developed. According to this model, kinetic constants, pre-exponential factors and activation energies have also been determined for low and high temperatures. (C) 2007 Elsevier Ltd. All rights reserved.