Table 1: Methane yields, lignin content, and concentration of available sugars of raw and PAP wheat straw.

Treatment (layer)Series nameVS load (gVS/L)Yield (mL CH4/gVS)Lignin (% of TS)1Total sugars (% of TS)2

Raw materialRAW10254.04 ± 19.4920.07.0
Single layer SIN10317.04 ± 19.4916.214.56
Top layerTOP10286.05 ± 7.3517.58.78
Mid layerMID10300.97 ± 0.091316.93
Bottom layer (low load)BOT55366.46 ± 9.367.228.43
Bottom layer (medium load)BOT1010311.58 ± 10.457.228.43
Bottom layer (high load)BOT2020277.96 ± 8.597.228.43

Strong acid hydrolysis; 2enzymatic hydrolysis.