Thermal behavior and general distributed activation energy model kinetics of Lignite–Chinese herb residues blends during co-pyrolysis

Abstract

In this work, the pyrolysis behavior of lignite, Chinese herb residues (CHR) and their blends were explored by thermogravimetric analysis. The co-pyrolysis improved the pyrolysis characteristic of lignite, leading to an increment of index D. Analysis results showed that 30%–50% of CHR add ratio was the appropriate choice for co-pyrolysis with lignite. It was clarified that synergetic effects between lignite with CHR occurred during the co-pyrolysis treatment. And the promoting effects were dominated at 240 °C to 310 °C, while it turned to inhibiting effects at 315 °C to 355 °C. The pyrolysis kinetic evolution was adapted by a new general distributed activation energy model with four pseudo-components. The simulation results demonstrated an excellent match with the adjusted coefficients Radj2 over 99.97%. In addition, G-DAEM further considered A-E kinetic compensatory effect. The outcomes enriched the applicability of this model in thermal process of other fuels.