Biogas upgrading, CO2 valorisation and economic revaluation of bioelectrochemical systems through anodic chlorine production in the framework of wastewater treatment plants

Pau Batlle-Vilanova; Laura Rovira-Alsina; Sebastià Puig; M Dolors Balaguer; Pilar Icaran; Victor M Monsalvo; Frank Rogalla; Jesús Colprim

doi:10.1016/j.scitotenv.2019.06.361

Biogas upgrading, CO₂ valorisation and economic revaluation of bioelectrochemical systems through anodic chlorine production in the framework of wastewater treatment plants

Sci Total Environ. 2019 Nov 10:690:352-360. doi: 10.1016/j.scitotenv.2019.06.361. Epub 2019 Jun 24.

Authors

Pau Batlle-Vilanova¹, Laura Rovira-Alsina², Sebastià Puig³, M Dolors Balaguer², Pilar Icaran¹, Victor M Monsalvo¹, Frank Rogalla¹, Jesús Colprim²

Affiliations

¹ FCC Aqualia, Department of Innovation and Technology, Avda. del Camino de Santiago, 40, Madrid, Spain.
² LEQUiA, Institute of the Environment, University of Girona, Campus Montilivi, Carrer Maria Aurèlia Capmany, 69, E-17003 Girona, Catalonia, Spain.
³ LEQUiA, Institute of the Environment, University of Girona, Campus Montilivi, Carrer Maria Aurèlia Capmany, 69, E-17003 Girona, Catalonia, Spain. Electronic address: sebastia@lequia.udg.cat.

PMID: 31299569
DOI: 10.1016/j.scitotenv.2019.06.361

Abstract

Biogas production in wastewater treatment plants (WWTPs) plays a decisive role in the reduction of CO₂ emissions and energy needs in the context of the water-energy nexus. The biogas obtained from sewage sludge digestion can be converted into biomethane by the use of biogas upgrading technologies. In this regard, an innovative water scrubbing based technology, known as ABAD Bioenergy® is presented and considered in this work. The effluents resulting from this system consist of biomethane and treated wastewater with a high CO₂ concentration. Therefore, the study explores the feasibility of using this CO₂-containing effluent in the cathode of a bioelectrochemical system (BES) for the transformation of CO₂ into methane. Techno-economic assessment of the process is presented, including the valorisation of anode reactions through the production of chlorine compounds. Finally, the potential impacts of applying this technology in a WWTP operated by FCC Aqualia are (i) increasing biomethane production by 17.4%, (ii) decreasing CO₂ content by 42.8% and (iii) producing over 60 ppm of chlorine compounds to disinfect all the treated wastewater of the plant.

Keywords: Anodic valorisation; Biomethane production; CO(2) reduction; Carbon capture and utilisation; Circular economy; Microbial electrosynthesis.