Pyrolysis characteristics, kinetics and evolved volatiles determination of rice-husk-based distiller's grains

摘要

Pyrolysis characteristics, kinetics and evolved volatiles of rice-husk-based distiller's grains (RHDG) were determined by thermogravimetric analysis and pyrolysis (Py)-GC/MS with rice husks (RH) as a comparison. The activation energy of RHDG was 239.84 ± 48.10 kJ/mol attained by Flynn-Wall-Ozawa method and 241.89 ± 49.78 kJ/mol by Kissinger-Akahira-Sunose method, much higher than RH and other biomasses. Diesel range organics account for 59.40%, 54.44%, 52.77% of volatiles obtained from RHDG pyrolysis, and C18, C16 were the most abundant components including oleic acids, octadecanoic acid and n-hexadecanoic acid. Pyrolysis evolved volatiles from RHDG had higher atomic H/C and O/C ratios compared with those from RH. The highest content in the volatiles from RHDG was acids (55.66%, 39.29% and 37.04% at 300 ℃, 400 ℃ and 500 ℃), which were mainly the evaporation of fatty acids in fermentation residues. Pyrolysis kinetics and evolved volatiles determination provide an in-depth understanding of rice-husk-based distiller's grains pyrolysis behaviors and basis for design and scale-up of pyrolysis process and reactor.