Innovative large-scale photobioreactor for coal propelled power plant effluents treatment

Abstract

This paper presents a phycoremediation technology application for effective wastewater treatment of two Israeli coal propelled power plants, one in Ashkelon (Rothenberg) and the second in Hadera (Orot Rabin). The technology is based on a new photobioreactor (PBR) at the heart of a biological integrative pollution prevention and control (Bio-IPPC) system. Unlike other known tubular and flat plate PBRs that are applicable in small Wastewater Treatment Plants (WWTP), this special PBR can be applied in large-scale domestic and industrial WWTPs. The unique PBR interior configuration, which includes multiple high porous polypropylene beds, enables the system to handle pollutants from both gaseous and aquatic effluents. Furthermore, while most existing algal-based technologies preserve cultured strains, this setup relies on WWTP habitat endemic flora. In the pilots of both power plants, the native biomass was single cyanobacteria Synechocystis salina, although the PBR photosynthetic composition can include multiple species of mixotrophic and/or autotrophic microorganisms. The results show that the photosynthetic biomass that grew on the PBR PP beds effectively assimilated the biomass nutrients such as nitrogen, phosphorous, magnesium, boron and calcium, and the toxic elements strontium and fluoride. Moreover, the system also mitigated greenhouse gas emission by the assimilation of bicarbonate (HCO3−) from the aquatic phase and CO2 from the gas phase.