Incorporated into both models is a waste water treatment system.
Waste water streams are treated in aerobic and anaerobic environments to produce clean process water, sludge, and
methane.
The sludge and methane are sent to the boiler.
Solid waste produced from the biorefineries includes ash from the boiler and gypsum produced during acid neutralization after pretreatment.
The gypsum could potentially be considered a byproduct, but in this LCA it is treated as waste.