Potential impacts of oxygen impurities in carbon capture and storage on microbial community composition and activity

Gaseous impurities, such as O2, are expected to be present within CO2 captured for storage. This could stimulate microbial activity in a geological storage site which has the potential lead operational issues injection well blockages, corrosion and oil souring. A series of experiments were carried out examine effect 10 ppm 100 O2 an anoxic (CO2 or N2) atmosphere on communities gas production laboratory scale experiments. Experiments inoculated with sulphate reducing bacteria enrichments compared uninoculated controls. The results show that H2S is delayed N2 atmosphere. resulted spike greater bacterial biomass when showed similar patterns regardless concentration. These suggest concentration lower than reduce growth sites. CH4 was observed some microcosms subsequent production, highlighting methanogenesis CCS reservoirs.