SNG from H2 and CO2 through Sabatier reaction is gaining interest to benefit from existing methane infrastructure both for storage and distribution. While a biogenic source of CO2 should be preferred few authors have addressed the issue in an experimental way. In a circular economy model, however, the use of wastewaters for H2-O2 co-production should be preferred, possibly with oxyfuel combustion of a biogenic carbon source.
The original WASYNG (WAstewaters SYnthetic NAtural Gas) circular concept considers Anaerobic Digestion (AD) of biomasses, biowaste and sewage, for biogas and digestate which provides water for electrolysis and sludge for char production through regenerative pyrolysis. The obtained char will be used for two purposes: to capture the CO2 contained in the biogas and so to separate it from the methane and also to produce other CO2 obtained from the oxyfuel combustion of char itself. In this way the two flows of CO2 will be used in the Sabatier reactor to produce synthetic natural gas (i.e. an electrofuel produced using hydrogen obtained from an electrolyser). Finally the synthetic natural gas will be used for cogeneration purposes.
Università di Pisa – prof. Desideri
Università di Perugia, Politecnico di Milano, Scuola Superiore Sant’Anna Pisa, Università di Genova
PROGETTO RILEVANTE INTERESSE NAZIONALE (PRIN)
CODICE: PROT. 2020AA9N4M – DURATA – 2022-2025