Table 1.
Features of enzyme and ethanol productions. Both CEF and SSF are carried out in batch operation. Carbon source A: pretreated liquid fraction, B: pretreated liquid fraction and molasses, and C: pretreated liquid fraction and pressed pretreated slurry with a total WIS content of 1%, 2%, and 3%; +: 1.5-fold specific activity.
| Reference | A | A+ | B | B+ | C1 | C2 | C3 | |
|---|---|---|---|---|---|---|---|---|
| Components into CEF, tonne/year | ||||||||
| Hexosans | — | 430 | 368 | 298 | 236 | 776 | 1374 | 1861 |
| Pentosans | — | 7 | 6 | 5 | 4 | 13 | 23 | 32 |
| Hexoses | — | 5133 | 3352 | 6242 | 4120 | 4812 | 4256 | 3805 |
| Pentoses | — | 1487 | 971 | 622 | 413 | 1394 | 1233 | 1102 |
| WISa | — | 806 | 690 | 558 | 442 | 1453 | 2575 | 3486 |
| C5 ratio in CEFb, % | — | 21 | 21 | 9 | 9 | 20 | 18 | 16 |
| WIS content in CEF, % | — | 0.5 | 0.7 | 0.8 | 0.9 | 1.0 | 2.0 | 3.0 |
| Productivity of CEFc, FPU/(L·h) | — | 70 | 107 | 154 | 230 | 75 | 84 | 93 |
|
| ||||||||
| Components into SSF, tonne/year | ||||||||
| Hexosans | 62980 | 62550 | 62612 | 62683 | 62745 | 62205 | 61606 | 61120 |
| Hexoses | 32634 | 27521 | 29304 | 30499 | 31228 | 27841 | 28397 | 28848 |
| Yeast | 3168 | 3160 | 3160 | 3160 | 3168 | 3144 | 3128 | 3112 |
| Enzyme protein | 1816e | 1656 | 1104 | 1682 | 1121 | 1651 | 1642 | 1635 |
| Mycelium | — | 1727 | 1152 | 1754 | 1170 | 1722 | 1713 | 1705 |
| WISa, ktonne/year | 117.98 | 117.55 | 117.61 | 117.68 | 117.74 | 117.19 | 116.59 | 116.09 |
|
| ||||||||
| Overall EtOH yieldd, L/dry tonne | 270 | 254 | 260 | 263 | 266 | 254 | 254 | 254 |
aIncludes hexosans and pentosans.
b(pentosans in ME + pentoses)/total sugar in ME.
cCorresponds to an enzyme fermentation time of 108 h.
dIncludes yeast and enzyme productions and ethanol losses in the process.
eThe purchased enzyme preparation was assumed to contain 10% protein.