Bioethanol produced from lignocellulosic biomass is a promising alternative for fossil fuel substitution. Hydrolytic lignin rich residues could be exploited through gasification for more efficient bioethanol production processes. The char gasification is generally one of the slowest thermal steps and a fundamental understanding of the heterogeneous reaction kinetics is needed forreactors design. The aim of this work was to investigate the kinetic behavior of chars from byproducts of 2nd generation bioethanol production. Two chars were studied: hydrolytic reed lignin and hydrolytic wheat straw lignin.Isothermal experiments, using temperatures from 725°C to 825°C were conducted in a thermobalance. The atmosphere was 50%(volmol%)steam and 50%(vol%)N2. Additional tests at 10% and 20% of steam (N2as complement) were performed in order to determine the effect of steam partial pressure. Additional sample characterizations, such as the proximate and ultimate analyses of the two residues, as well as the metals content in chars, and morphological characterization were also performed. The apparent activation energy, Ea, of steam-char reaction was determined at different degrees of char conversion. The results showed that the Eaincreases with conversion for both samples, ranging from 135 to 188 kJ/mol. © 2016 ETA-Florence Renewable Energies.
Steam gasification of agro-industrial lignocellulosic residues from bioethanol industry
Cerone, N.;Zimbardi, F.
2016-01-01
Abstract
Bioethanol produced from lignocellulosic biomass is a promising alternative for fossil fuel substitution. Hydrolytic lignin rich residues could be exploited through gasification for more efficient bioethanol production processes. The char gasification is generally one of the slowest thermal steps and a fundamental understanding of the heterogeneous reaction kinetics is needed forreactors design. The aim of this work was to investigate the kinetic behavior of chars from byproducts of 2nd generation bioethanol production. Two chars were studied: hydrolytic reed lignin and hydrolytic wheat straw lignin.Isothermal experiments, using temperatures from 725°C to 825°C were conducted in a thermobalance. The atmosphere was 50%(volmol%)steam and 50%(vol%)N2. Additional tests at 10% and 20% of steam (N2as complement) were performed in order to determine the effect of steam partial pressure. Additional sample characterizations, such as the proximate and ultimate analyses of the two residues, as well as the metals content in chars, and morphological characterization were also performed. The apparent activation energy, Ea, of steam-char reaction was determined at different degrees of char conversion. The results showed that the Eaincreases with conversion for both samples, ranging from 135 to 188 kJ/mol. © 2016 ETA-Florence Renewable Energies.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
