Application of microalgae cultivated on pine bark for the treatment of municipal wastewater in cylindrical photobioreactors.

The presented study concerns the efficiency of removing nutrients, organic compounds and metal cations from municipal sewage by a cylindrical photobioreactor (PBR) with the biomass of microalgae growing on pine bark. The study was conducted in two cylindrical PBRs fed with municipal wastewater for 42 days. PBRs were internally illuminated with red and blue light at night. The sewage was additionally enriched in CO2 and CaCO3. The concentration of NH4+, NO32−, PO43−, metal cations and organic carbon (TOC) was determined in the treated sewage. The results indicated that the development of algal‐bacterial biofilm contributed to the reduction of NH4+ (>99%), PO43− (96–99%) and TOC (71–77%) concentrations. Amongst the metal cations, the highest reduction of concentration was noted for Cu, K, Mn, Zn and Fe. Immobilisation of algae on pine bark is an effective method of wastewater treatment in PBR and supports the separation of proliferated biomass. [ABSTRACT FROM AUTHOR]