Figure 2.

Different process schemes which were evaluated for biological hydrogen production (ΒHP) of grass lawn (GL) (EH: enzymatic hydrolysis): (a) the whole slurry of all thermo-chemical pretreatments was used for BHP in SSF (simultaneous saccharification and fermentation) mode. The whole slurry of pretreatment with H₂SO₄ and NaOH, 10 g/100 g TS was used (b) directly for BHP without addition of enzymes, (c) or in a separate hydrolysis and fermentation (SHF) scheme (d) or separated and the liquid fraction was used for BHP without enzyme addition, whereas the solid fraction was used in an SSF concept.