and similar to the values reported for sewage sludge mesophilic digestion
[4,19]. The values of pH, alkalinity, and concentration of ammonia
and VFA were measured at the end of the experiments corroborated
that the digesters operated at optimumconditions. The biogas composition,
analysed several times during the experiments, indicated that the
methane percentage ranged between 66% and 71% in all reactors.
The methane production from both microalgae species shows that
biomass cultivation in wastewater coupled to anaerobic digesters allows
wastewater treatment and energy recovery simultaneously. During
the wastewater treatment process, the TN concentration reduction
can lead to high lipid content in biomass; a high lipid content increases
the methane production potential of the biomass.