| Abstract |
The Experimental Geochemistry Laboratory (EGL) at GNS has expanded its capabilities into the supercritical pressure-temperature region through new equipment purchases and the support of funding from the Geothermal: The Next Generation (GNG) programme. With experimental work spanning water-rock interactions, mineral solubilities, tracer suitability, scaling/corrosion simulations, and CO2 reinjection, the laboratory contributes to advancing geochemical understanding and industry practices in the conventional geothermal setting. With the expanded capability the lab is able to conduct such studies at the more extreme temperature and pressure conditions of the supercritical environment. The newly acquired apparatus is capable of reaching up to 700°C and pressures of 300 bars. Experimental work at supercritical conditions completed to date includes water - basalt interaction, water/brine - greywacke interaction, CO2 – brine coinjection into greywacke, mineral solubility (quartz and anhydrite), and tracer stability studies. These experiments aid in understanding the effects of water-rock interaction at supercritical conditions on host rocks, assessing aquifer permeability modifications, and evaluating corrosion and scaling issues in geothermal reservoirs and power station infrastructure. The EGL is recognized for innovative research and robust scientific advice, the laboratory serves as a hub for sustainable geothermal development, collaborating with industry stakeholders and academia. Its work not only enhances New Zealand's geothermal future but also contributes to global efforts for better sustainability, higher efficiency, and a reduced carbon footprint in geothermal energy production and utilization. |