Characteristic and kinetics of corn stalk pyrolysis in a high pressure reactor and steam gasification of its char

Pyrolysis characteristics of the corn stalk were investigated at different temperatures and pressures, with focus mainly on the releasing profiles and forming behaviors of gas. The results show that a higher pressure was conducive to the yield of H2 and CH4, and was not conducive to the generation of CO. Combustible gas components increase with the increase temperature. H2 concentration was affected significantly by temperature, was mainly released at higher temperatures (>500 °C). At 700 °C, the combustible gas components are up to 90% and H2 concentration is up to 51.78%. The gas components of corn stalk pyrolysis char steam gasification mainly consisted of CO and H2, 25.7% and 50.7% respectively. The calorific value of gasification gas is up to 9508.9 kJ/M3. A kinetic study of the pyrolysis process of the corn stalk was investigated using a thermogravimetric analyzer. As the heating rate increased, the activity energy reduced. By using the Popescu method to determine that shrinking core model can reflect the pyrolysis process of corn stalk truly at low temperature pyrolysis, and chemical reaction model can reflect the pyrolysis process of corn stalk truly at high temperature pyrolysis. Experimental results showed that values of kinetic parameters can be successfully used to understand the degradation mechanism of solid-state reaction.