Improving Biomethane Production and Mass Bioconversion of Corn Stover Anaerobic Digestion by Adding NaOH Pretreatment and Trace Elements

Table 7

System stability of anaerobic digestion.

Different groups	pH	Ammonia nitrogen (mg/L)	Alkalinity (mg/L)	Volatile fatty acids (mg/L)
A1B3C2	7.44 ± 0.02	490 ± 30	8550 ± 850	269 ± 50
NaOH-pretreated	7.45 ± 0.02	518 ± 56	10700 ± 300	511 ± 10
Untreated	7.47 ± 0.02	490 ± 42	9255 ± 225	785 ± 21