Low temperature oxidation and its kinetics of cornstalk chars. (15th November 2016)

• Record Type: Journal Article
• Authors: Fan, Penghui; Fan, Shuang; Sheng, Changdong
• Is Part Of: Fuel. Volume 184(2016)
• Page Start: 915
• Page End: 921
• Publication Date: 2016-11-15
• Subjects: Cornstalk char -- Self-heating -- Low temperature oxidation -- Kinetic analysis; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2016.04.072
• Languages: English
• ISSNs: 0016-2361

Abstract

Highlights: 500 °C and 250 °C chars were generated from pyrolyzing cornstalk. TGA–DSC and isothermal calorimetry enabled describing char low temperature oxidation. Kinetic analysis was performed based on TGA–DSC and isothermal calorimetry. 500 °C char is more reactive than 250 °C char and cornstalk. Torrefaction at 250 °C slightly reduced self-heating propensity of the cornstalk. Abstract: The present work was addressed to low temperature oxidation and its kinetics of biomass chars. A cornstalk was pyrolyzed at 500 °C and 250 °C. The resulting chars and the cornstalk were subject to thermo-gravimetric analysis and differential scanning calorimetry (TGA–DSC) and isothermal calorimetry. The results demonstrated that combining the two thermal analyses enabled describing the low temperature oxidation behavior of the chars from close to room temperature to ignition. The derived activation energies from both techniques were well within the range of TGA and DSC measured values for various carbonaceous materials in the literature. Comparisons indicated that 500 °C char exhibited higher heat generation reactivity than 250 °C torrefied char and the cornstalk. Both TGA–DSC and isothermal calorimetry showed that the 250 °C char was slightly less reactive than the cornstalk, implying that torrefaction at 250 °C is potential to reduce the proneness of the cornstalk to self-heating.