Life cycle impacts of ethanol production from spruce wood chips under high-gravity conditions

Table 2 Reduction in the environmental impacts due to enzyme recycling

Process configuration	Reduction of environmental impacts
Process configuration	GWP [%]	EP [%]	AP [%]	POCP [%]
Base case	19	20	13	20
Highest yield at 20 % DM	18	18	14	21
Highest yield at 30 % DM	20	17	14	22

Impacts of an enzyme recycling rate of 25 % were compared with the impacts of no enzyme recycling. This was done for the: a. base case (detoxification with \({\mathrm{Na}_2\mathrm{S}_2\mathrm{O}_4}\), PSSF at 12 % DM and 30 °C; b. process configuration with the highest yield at 20 % DM (washing of slurry, PSSF at 40 \(^\circ\)C); c. process configuration with the highest yield at 30 % DM (adaptation of yeast + extra nutrients, SHF at 30 °C)

ISSN: 2731-3654