BIOFIDS (Photobioreactor for the biological de-sulphurisation of biogas) is a project that aims at the technological transfer of the ENEA patent N° 0001428761 “LED photobioreactor plant for the biological removal of H2S from biogas. This will be made by the realization of a prototype plant based on the process of anoxygenic photosynthesis operated by Green Sulphur Bacteria through which H2S is oxidized to sulphur in the presence of light. One of the main obstacles to the exploitation of biogas as produced by anaerobic digestion is the presence of H2S, which is a pollutant with toxic effects on humans and agro-ecosystems and also causes the corrosion of gas collection lines and mechanical equipment related to energy generation. The complete removal of H2S is also an essential step in the production of biomethane to be fed into the natural gas distribution network or used as biofuel. In the plant, H2S is converted into bio-sulphur through bacterial photosynthesis, which is made particularly efficient by monochrome LEDs. The absence of chemical reagents makes this technology sustainable and competitive with conventional systems. The bio-sulphur, the only by-product of the process, has soil amendment and phytosanitary properties and its possible exploitation in the agronomic sector has been assessed.
The partner companies are TECNODELTA srl, ACDA spa and RAMS&E srl, and the involved research center are ENEA, Polytechnic of Turin and Environment Park
THE ROLE OF ENVIPARK
Envipark, in collaboration with Polito, technical consultant of ACDA in the context of the project, and with the ENEA research group, took part in the preliminary studies of prototyping and biology of the BIOFIDS project. Batch experiments were carried out to test the growth and stability of the Chlorobium Limicola bacterium, in the presence of biogas from ACDA srl’s plant, in order to verify the bacterium’s resistance to the pollutants present in the biogas and its tolerance to H2S concentration.