An Estimate of Energy Available via Microbial Sulfate Reduction at a Quaternary Aquifer in Northern Japan considered for Low Temperature Thermal Energy Storage

Abstract

Abstract:The energy available via microbial sulfate reduction was estimated for a Quaternary aquifer in northern Japan that is a candidate site for low temperature aquifer thermal energy storage. In evaluating whether microbial sulfate reduction proceeded or ceased, it was assumed that electron donor/acceptor concentrations were unchanged by temperature increase. The estimated energy availability via microbial sulfate reduction at 9 °C with no thermal disturbance was 37, 51, and 53 kJ·(mol SO at 60 °C. These results indicate that possible energy availability via microbial sulfate reduction at approximately 40-60 °C exceeded the range of available energy (compiled from previous studies) at which sulfate reduction would cease. Thus, microbial sulfate reduction at this site may proceed at approximately 40-60 °C.