Oil palm biomass is high C:N ratio and unsuitable for anaerobic
digestion. The optimization condition methane production from oil
palm biomass by SS-AD was F:I ratio of 2:1, C:N ratio of 30:1 and
16% TS. EFB is more suitable for methane production by SS-AD than
OPF and OPT. Suitable F:I, % TS and C:N ratio could balanced microbial
population with increased methane production and cellulose
degradation. Microbial community in SS-AD was dominated by
bacteria consist of Ruminococcus sp. and Clostridium sp. and
archaea consist of Methanoculleus sp. SS-AD has potential to treat
oil palm biomass for bioenergy production.