Carbon Capture Utilisation and Storage Flashcards
What are some methods of capturing carbon?
Direct Air Capture (DAC), afforestation, habitat restoration, use of biomaterials, biocatalytic conversion, biochar and carbon negative concrete
What are some utilisation methods for carbon?
Chemical conversion, use in food growth, use in fizzy drinks, enhanced oil recovery, enhanced rock weathering, biocatalytic conversion, biochar and carbon negative concrete
What are some storage methods of carbon?
Geological storage, afforestation, habitat restoration, enhanced oil recovery, enhanced rock weathering and carbon negative concrete
What are some soil management practices that reduce carbon loss?
Reduced tillage, use of cover crops and erosion control (contour ploughing, terracing)
What can increase carbon input into soil sequestration of farms?
Addition of organic amendments (compost, manure and crop residues)
What is carbon negative concrete?
Replacing cement in the concrete mix with steel slag and injecting wet concrete with CO2 to cure it, giving it strength
What is biochar?
Charcoal produced by pyrolysis of biomass in the absence of oxygen, it is used as a soil amendment
What is enhanced rock weathering and how does it capture carbon?
Carbonic acid rainfall combines with spread silicate rock, which traps the carbon in bicarbonate form, nutrients from the rock improve soil health and crop yield, bicarbonate wash into the ocean and fall to sea-floor, permanently locking away the carbon, alkaline bicarbonates also combat ocean acidification
What are the key attributes for geological reservoir for carbon storage?
Porous, permeable, >800m, caprock integrity, containment and accessibility
What is residual trapping?
CO2 is immobilised in pore spaces as disconnected droplets or bubbles, trapped by capillary forces during the movement of formation fluids
What is structural trapping?
CO2 is physically contained beneath impermeable rock layers (caprock) in geological structures such as anticlines or fault traps
What is solubility trapping?
CO2 dissolves into formation water, becoming part of the fluid phase and reducing its potential to migrate
What is microbial cycling of carbon?
CO2 is converted into biomass or other forms through microbial metabolic processes
How can precipitation trap carbon?
CO2 reacts with minerals in the host rock to form stable carbonate minerals, locking carbon away in solid form
What is adsorption to coal?
CO2 is adsorbed onto the surface of coal seams, replacing methane and becoming physically retained in the coal matrix
What are some of the risks of containment?
Pressure build-up within the reservoir, leaks into wells, changes in stress may induce seismicity
What environmental conditions can effect the biogeochemical reactions of CO2?
pH, temperature, salinity, TDS, pressure, organic C, e donors and e acceptors and microbiota
