Heat Recovery Potential and Hydrochemistry of Mine Water Discharges From Scotland’s Coalfields

Prospective and operational mine water geothermal projects worldwide have faced challenges created by chemistry (e.g., iron scaling, corrosion) high expenditure costs drilling or pumping costs) among others. Gravity fed actively pumped drainages can be cheaper sources of low-carbon heating when coupled with adequately sized heat exchanger pump hardware. They also provide valuable chemical data to indicate quality associated coalfields. Field collection temperature flow rate from discharges across the Midland Valley Scotland, combined existing for Coal Authority treatment schemes suggest that pumps could a total up 48 MW energy. Chemical characterisation waters research area has hydrochemical database project stakeholders investigating systems using boreholes cooling purposes. Hydrochemical analytical assessment untreated gravity found most are circumneutral, non-saline an interquartile range 2.0–11.6 mg/L. Stable isotope analysis indicates dominated recent meteoric waters, but origin sulphate in is not as simple coal pyrite oxidation, rather more complex, mixed origin. Untreated contribute 595 kg/day Scottish watercourses; thus, it recommended constructed, they co-designed networks.