Optimization of the BornBiofuels 2nd generation bioethanol concept
There has been a further development regarding the manufacturing of bio ethanol from straw and other residues, were the production prices has been reduced to 2 kroners per liter bio ethanol.
The concept which formes the fundament for the upbringing of the demonstration plant BornBiofuel on Bornholm, involves pre-treatment of biomass, enzymatic hydrolysis of cell parts and fermentation of the so called C5 and C6 notch for ethanol. The refractors consist partly of lignin, which can be used as fuel and for manufacturing chemicals, and partly fraction, which can be used for production of biogas. The project has tested the pre-treatment of wetexplosion on straw and different kinds of grass species such as doggrass, styregrass, swingle, styreswingle and lucerne. By composing a pre-treatment on 150 degrees Celsius for 15 min. and a supplement of 0.3% sulphuric acid it shown that the ethanolprofit, on bothe doggrass and straw, was about 300 l pr. Tons solids. Out of this about a third comes from the fermentation of the C5 sugar. In combination with the reduction of the enzyme prices and the advantage there is to find in combining the production of bioethanol and biogas, we might be looking at a price of only 2 kr. pr. Litre bioethanol. (Forskning i Bioenergi, Brint og Brændselsceller, nr. 41 september 2012)
The execution of the project for optimization of the BornBiofuels 2nd generation bioethanol concept has led to significant performance improvements in the modified BornBiofuel concepts. The modifications include:
- The tailoring of the concept to more potential biomass resources (WP1)
- A higher efficiency of the wet explosion pretreatment to achieve higher sugar release and reduce processing costs (WP2)
- The development of suitable and efficient separation technologies (WP3)
- Reduced costs for enzyme and nutrient addition for the hydrolysis and fermentation processes (WP4 and WP5)
- Higher fermentation yields in both C6 and C5 fermentation processes (WP5 and WP6)
- A more simple design of enzymatic hydrolysis and fermentation (WP5 and WP6)
- Full utilization of the residual organic matter for biogas production (WP7)
- Implementation of wastewater reuse in the concept (WP8)
With these improvements the overall ethanol yield in the modified BornBiofuels concept is 20% to 30% higher than in the previous concept. This affects almost all process steps since the amount of raw material required to produce 100 million liter per year decreases, which in turn reduces the size of the equipment. The MESP (Minimum Ethanol Selling Price) resulting from the improvements of the different stages of the BornBiofuel concept was calculated to 3.00 DKK/L for a current scenario and to 1.80 DKK/L in an nth plant scenario with further improvements (for example enzyme costs). The internal rate of return in the nth plant case was 10%, suggesting that the production of cellulosic ethanol will become not only cost efficient but also economically viable, even in a Danish scenario.
Key figures
Category
Participants
| Partner | Subsidy | Auto financing |
|---|---|---|
| BIOGASOL ApS | 4,49 mio. DKK | 4,49 mio. DKK |
| Aalborg Universitet (Fredrik Bajers Vej) | 2,33 mio. DKK | 0,39 mio. DKK |
Contact
Aalborg Universitet (AAU). Institut for Kemi, Miljø og Bioteknologi. Center for Bioteknik
Lautrupvang 15
DK-2750 Ballerup
www.bio.aau.dk
Uellendahl, Hinrich , 99402585, hu@bio.aau.dk
Øvr. Partnere: Biogasol ApS
