초록
<P><B>Abstract</B></P> <P>The present work investigates the suitability of pretreated corn stover (CS) to serve as feedstock for high gravity (HG) ethanol production at solids-content of 24wt%. Steam explosion, with and without the addition of H<SUB>2</SUB>SO<SUB>4</SUB>, and organosolv pretreated CS samples underwent a liquefaction/saccharification step followed by simultaneous saccharification and fermentation (SSF). Maximum ethanol concentration of ca. 76g/L (78.3% ethanol yield) was obtained from steam exploded CS (SECS) with 0.2% H<SUB>2</SUB>SO<SUB>4</SUB>. Organosolv pretreated CS (OCS) also resulted in high ethanol concentration of ca. 65g/L (62.3% ethanol yield). Moreover, methane production through anaerobic digestion (AD) was conducted from fermentation residues and resulted in maximum methane yields of ca. 120 and 69mL/g volatile solids (VS) for SECS and OCS samples, respectively. The results indicated that the implementation of a liquefaction/saccharification step before SSF employing a liquefaction reactor seemed to handle HG conditions adequately.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Steam explosion and organosolv pretreatment were applied on corn stover (CS). </LI> <LI> The effect of H<SUB>2</SUB>SO<SUB>4</SUB>-catalyzed steam explosion on CS digestibility was investigated. </LI> <LI> CS was liquefacted/saccharified with a free-fall mixer at high-solids content. </LI> <LI> Maximum ethanol concentration and yield was ca. 76g/L and 78.3%, respectively. </LI> <LI> Biomethane production was conducted from ethanol fermentation residues. </LI> </UL> </P>