Fast co-pyrolysis of biomass and lignite in a micro fluidized bed reactor analyzer

• Synergetic effect of fast co-pyrolysis of biomass and lignite was investigated.
• Iso-conversional method was used to analyze kinetics under isothermal condition.
• Activation energies for each individual gas products were calculated.
• Reaction mechanisms for co-pyrolysis were evaluated.

The co-pyrolysis characteristic of biomass and lignite were investigated in a Micro Fluidized Bed Reaction Analyzer under isothermal condition. The synergetic effect was evaluated by comparing the experimental gas yields and distributions with the calculated values, and iso-conversional method was used to calculate the kinetic parameters of formation of each gas component. The results showed that synergetic effect was manifested in co-pyrolysis. For the range of conversion investigated, the activation energies for H2, CH4, CO and CO2 were 72.90 kJ/mol, 43.90 kJ/mol, 18.51 kJ/mol and 13.44 kJ/mol, respectively; the reactions for CH4 and CO2 conformed to 2 order chemical reaction model, and for H2 and CO conformed to 1.5 order chemical reaction model; the pre-exponential factors for CH4, CO2, H2 and CO were 249.0 S−1, 5.290 S−1, 237.4 S−1 and 2.693 S−1, respectively. The discrepancy of the kinetic parameters implied that there were different pathways for forming the different gas.