The consortium has already tested INCOVER technologies individually at lab scale. The innovation of INCOVER project comes from the combination of all INCOVER technologies, for a bio-production and resource recovery-based wastewater treatment. The description of each technology is as follows:
PHOTOSYNTHETIC BIOGAS UPGRADING AT A DEMO SCALE IN OPEN AND ENCLOSED PHOTOBIOREACTORS
The upgrading of biogas based on the symbiotic interactions between microalgae and bacteria represents nowadays the only biotechnology capable of simultaneously removing multiple biogas pollutants such as CO2 and H2S. This novel biogas upgrading biotechnology relies on a solar driven fixation of CO2 by photosynthesis, concomitantly with the bacterial oxidation of H2S to SO42− using the O2 photosynthetically produced. The high pH (9-10) imposed by photosynthesis supports an enhanced CO2 and H2S gas-liquid mass transport in the system. This technology is typically implemented in a biogas scrubbing unit interconnected with a photobioreactor (Figure 1). The physical separation of biogas scrubbing and photosynthetic CO2 fixation has been consistently shown as the most effective strategy to support high CO2 removal efficiencies with a limited desorption of N2 and O2 from the algal cultivation broth to the biomethane. This technology is being implemented in 10 m3 open high rate algal ponds (at Chiclana de la Frontera) and 10 m3 enclosed photobioreactors (in Barcelona) under the frame of the H2020 project INCOVER. An optimization of the gas-liquid mass transfer in the biogas absorption column conducted at Chiclana de la Frontera site using raw domestic wastewater and centrate has achieved CH4 concentrations ~ 90%. These experiments were conducted at biogas flow rates ranging from 275-450 l/h and liquid/biogas ratios of 1.2 and 2.1. The O2 and N2 content in the biomethane produced increased when increasing the liquid/biogas ratio in the system. A similar process optimization is being carried at Agropolis site in Barcelona. In addition, this technology supported also a cost-effective wastewater treatment, which represent another advantage compared to conventional physical-chemical technologies.
Rodero M.R, Marín D, Lebrero R, Muñoz R (Universidad de Valladolid)
Ugetti E, García J ( Universitat Politécnica de Catalunya)
Lara E, Rogalla F (FCC-Aqualia S.A)