Wood-burning processes in variable oxygen atmospheres: Thermolysis, fire, and smoke release behavior

• The thermolysis/burning behavior of wood under different oxygen concentrations is studied. • The oxygen concentrations affect the wood thermolysis and then influence the release of combustible fuels. • A controlled atmosphere smoke chamber (CASC) is constructed to analyze the heat and smoke release. • The higher the oxygen concentration, the more fully the wood burns and the higher the heat release. • The effect of variable oxygen concentration during wood-burning processes is revealed. Revealing the effect of variable oxygen concentrations during wood-burning processes, have great importance for understanding the wood-burning behavior and drawing attention to the properties of burning lignocellulosic biomass. Herein, we focus on the thermal decomposition and burning behavior of wood in a variable oxygen atmosphere. The thermal-decomposition products and the kinetic analysis are verified combining the thermogravimetric analysis (TGA), TGA-FTIR, and TGA-MS. Although the main thermolysis products are similar at different oxygen atmospheres, the thermal-decomposition follow different reaction mechanisms, obtained by the calculated kinetic parameters. The combustibility is explored by the micro-scale combustion calorimeter that analyzes the heat release capacity, peak heat release rate, and total heat release. The oxygen concentrations affect the thermal-decomposition of woods and then influence the release of combustible fuels. Further, we construct a controlled atmosphere smoke chamber (CASC) to analyze the heat and smoke release during the burning of variable oxygen concentrations. The oxygen concentrations exhibit competition between inhibiting and promoting combustion, thus leading to the max smoke release at 19 vol% oxygen concentration. Overall, the combustion parameters at different oxygen concentrations obtained in our study reveal the role of oxygen concentration in the wood-burning processes and have positive implications for understanding the wood-burning behavior.