detector were at 120, 40 and 100 C, respectively (Mamimin et al.,
2012). The gas sample of 1 ml was injected in duplicate. Theoretical
methane potential was calculated according Bushwell’s formula
that is derived by stoichiometric conversion of the compound to CH4, CO2 and NH3. It is assumed that the averaged chemical compositions
of VS in EFB, OPF and OPT are VScarbohydrate(C6H10O5).
Methane and energy yields are expressed as m3 CH4 ton1 wet
weight. The thermal energy content of the methane was calculated