This study proposes potential replacement for the Portland-based cement, which is a common sealant used in deep high-temperature geothermal wellbore completions. The experimental laboratory studies were focussed on alkali-activated aluminosilicates. It was proven, that the so-called, geopolymer-based sealing systems exhibit high compressive and flexural strength at elevated temperatures, good resistance towards thermal cyclic loading, high ductility, acid insensitivity, and improved water permeability. Additionally, alkali-activated aluminosilicate sealing systems are economically feasible and their CO2 emission, during the manufacturing process, is significantly lower in comparison with the conventional Portland-based cement types, making them an environmentally friendly option for deep wellbore completions in unconventional high-temperature geothermal systems.
- Wellbore integrity
- Geothermal wellbore completion
- SHGS (Super-hot Geothermal Systems)