The widespread deployment of commercial‐scale cellulosic ethanol currently hinges on developing and evaluating scalable processes whilst broadening feedstock options. This study investigates whole Eucalyptus grandis trees as a potential feedstock and demonstrates dilute acid pre‐treatment (with steam explosion) followed by pre‐saccharification simultaneous saccharification fermentation process (PSSF) as a suitable, scalable strategy for the production of bioethanol. Biomass was pre‐treated in dilute H2SO4 at laboratory scale (0.1 kg) and pilot scale (10 kg) to evaluate the effect of combined severity factor (CSF) on pre‐treatment effectiveness. Subsequently, pilot‐scale pre‐treated residues (15 wt.%) were converted to ethanol in a PSSF process at 2 L and 300 L scales. Good polynomial correlations (n = 2) of CSF with hemicellulose removal and glucan digestibility with a minimum R2 of 0.91 were recorded. The laboratory‐scale 72 h glucan digestibility and glucose yield was 68.0% and 51.3%, respectively, from biomass pre‐treated at 190 °C /15 min/ 4.8 wt.% H2SO4. Pilot‐scale pre‐treatment (180 °C/ 15 min/2.4 wt.% H2SO4 followed by steam explosion) delivered higher glucan digestibility (71.8%) and glucose yield (63.6%). However, the ethanol yields using PSSF were calculated at 82.5 and 113 kg/ton of dry biomass for the pilot and the laboratory scales, respectively. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd

No abstract

No abstract

No abstract

No abstract

Whole Eucalyptus grandis trees (including bark, branches and leaves) were investigated as a potential feedstock for bioethanol production. To demonstrate and maximize ethanol production, unwashed steam exploded wood chips (SEWC) were used as substrates in high solids load simultaneous saccharification fermentations (SSF) with an industrial Saccharomyces cerevisiae strain (Fali Ò ). Under optimized SSF conditions-20 wt% solids, 60 filter paper units (FPU)/g glucan, and 36°C-ethanol titer and glucan-to-ethanol yields of 56 g/L and 90%, respectively, were achieved. Raising the SSF temperature to 39°C showed no observable benefit in final ethanol titers and/or yields. Addition of 3 wt% polyethylene glycol (PEG) further increased final ethanol titers and yields to 60 g/L and 95%, respectively, at a 30% lower cellulase dosage. Considering the mass balance of the best-performing SSF (20 wt% SEWC, 40 FPU Ctec 2/g glucan, 30 mg PEG/g dry solid at 36°C) process, the maximum ethanol attainable was estimated at 187 kg (85.8% yield) and 299 kg (95% yield) per dry metric ton of original and SEWC biomass, respectively.

No abstract

No abstract