Biotreatment of landfill leachate by microalgae-bacteria consortium in sequencing batch mode and product utilization

Biotreatment of leachate by microalgae-bacteria in a sequencing batch mode using a photobioreactor was investigated. The microalgae-bacteria biomass initial concentration was maintained at 3:1 ratio. The increase in the initial concentration of the biomass in the 2nd batch favoured biomass growth, doubling biomass productivity, compared to the 1st batch. In both batches, N-NH4 was completely removed from the leachate. In the 2nd batch, the nitrate, COD and phenol removal efficiencies were above 90%. The relative toxicity reduced from 57.32 to 1.12% at the end of 2nd batch. The fatty acids content (C16-18) varied from 85.47 to 87.65% for the 1st batch and 86.72 to 87.69% for the 2nd batch. The crude glycerol content varied from 34.54 to 42.36% for the 1st batch and 33.64 to 39.55% for the 2nd batch. The coexistence of microalgae and bacteria played an important role in leachate treatment and biomass production for biorefinery purposes.