Biomass & Bioenergy, Vol.95, 99-108, 2016
Energy self-sufficient production of bioethanol from a mixture of hemp straw and triticale seeds: Life-cycle analysis
Industrial hemp shows exceptional potential for cellulosic ethanol production, especially regarding yields per hectare, costs and environmental impact. Additionally, co-products, such as high-value food-grade oil, increase the value of this plant In this work, hemp straw was steam-exploded for 45 min at 155 degrees C and hydrolysed with a cellulase/xylanase mixture. Up to 0.79 g g(-1) of cellulose was degraded and subsequent simultaneous-saccharification-and-fermentation with added triticale grist resulted in >0.90 g g(-1) fermentation of cellulose. Hemp straw is very suitable, as it contains 0.63 g g(-1) of cellulose and only 0.142 g g(-1) of hemicellulose. A 2000 m(3) a(-1) ethanol biorefinery requires a land use of 3 km(2) each for hemp and for triticale. A total of 2630 kg ethanol and 150 kg hemp oil can be gained from 1 ha. Slurry and triticale straw serve as raw material for the biogas fermenter or as animal feed. Biogas supplies thermal and electric energy in combined heat and power. Ethanol will remain at 0.66 is an element of dm(-3) based on market prices. In addition, data have been calculated for market prices plus and minus 30% market prices (0.51-0.81 is an element of dm(-3)). Carbon dioxide (CO2) abatement for ethanol achieves 121 g MJ(-1) CO2eq for a combined ethanol/biogas plant. The CO2 abatement costs vary from 38 to 262 is an element of t(-1) CO2eq. (C) 2016 Elsevier Ltd. All rights reserved.