Evaluating the impact of wood sawdust and peanut shell mixing ratio on co-combustion performance

Abstract

Mixed combustion of different biomass fuels often occurs in household stoves and biomass boilers, depending on the economy and availability. It has been verified that the co-combustion of agricultural and forestry residues with coal and plastics can significantly improve combustion efficiency and reduce carbon emissions. This study focused on the long-neglected co-combustion of agricultural and forestry residues. Kinetic and thermodynamic analyses of five types of pellets made of wood sawdust (WS) and peanut shell (PS) with different mixing ratios were conducted based on data from a thermogravimetric analyzer. Real combustion experiments in a force-draft biomass stove were conducted, and the nitrogen oxides (NOx) and carbon monoxide (CO) emissions of the five pellets were discussed. Our study showed that the combustion performance of mixed fuel (including the flammability index, burnout index and comprehensive combustion index) is improved to varying degrees compared to that of WS. The combustion mechanism, activation energy, and other thermodynamic parameters can vary with the mixing ratio. All three mixed fuels significantly reduced CO emissions while increasing NOx emissions. Our study revealed the dynamics, thermodynamics, emission performance and other parameters of the co-combustion of WS and PS.