Acoustic Emission and Guided Wave condition monitoring techniques promising candidates for casing integrity assessment
Geothermal wells capture energy from the earth and could be an extremely efficient way to address climate change. Adequate inspection of the well casings is a key part of well management. S4CE partner TWI is under the process of identifying the most appropriate techniques for monitoring geothermal well casings, with the objective of the identification of failure and consequently avoiding it at lower maintenance costs. Acoustic emission and guided wave techniques have been tested in typical casing from a geothermal field site in Cornwall. The results have shown a promising attenuation rate for a certain range across the casing. A potential combination of the two techniques could be a promising solution for condition monitoring of geothermal well casings. Read the full article here
With the rising threat of the consequences of climate change and the negative impact of air pollutants on human’s, and more widely the biosphere’s well-being, it has become ever more important to establish accurate and reliable monitoring systems of gaseous emissions released in the atmosphere. Whenever gaseous emissions occur, such systems are crucial to help answer important questions and support targeted action. What are the gasses being emitted? Where are the emission sources located? How much gas flux is being emitted? What are the processes leading to these releases? How can these emissions be reduced? Have targeted actions succeeded in reducing emissions? Field gas monitoring technologies provides quantitative information for site characterisation, legislation enforcing, decision making, mitigation assessment and transparency that supports a wiser use of natural resources. Read the full article here
In the framework of S4CE, ETH Zürich is developing a DNA-based tracer technology for surface and underground tracing. The DNA is adsorbed onto sub-micron silica particles and coated with a shell to increase the DNAs stability and applicability for tracing. Barcodes, as created with unique DNA sequences allow for multitracing applications in various tracing scenarios. ETH Zürich’s role within S4CE is to assess the environmental impact of large-scale tracer use by establishing an ecotoxicological profile through acute and chronic ecotoxicity assays.
The key parameter for the efficiency of a geothermal system is the hydraulic conductivity in the subsurface. Fluid circulated between injection and production wells follows natural pathways, which cannot directly be mapped by geophysical measurements. Q-con GmbH have developed a new methodology where they use tiny earthquakes for measuring the hokydraulic pressure along these pathways. Measurements are used to calibrate computer models of the subsurface reservoir.
In order to better trap CO2 in the subsurface, it is important to understand how the CO2 molecules interact with different substrates in diverse geological situations. SCM, a Dutch computational chemistry software company, is developing software tools that will allow researchers to simulate those interactions in a computer. With the aid of those simulations, scientists will be able to build models pointing to the best ways to trap CO2 underground, for example within basalt rocks.