Activity: Talks and presentations › Conference presentations
Description
In a one hour invited lecture, the topics "Natural Sources for Carbon Dioxide" and "Direct Air Capture" were covered in a comprehensive lecture during the workshop.
Direct air capture (DAC) can extract carbon dioxide directly from the atmosphere for subsequent and permanent storage in deep geological formations (achieving negative CO2 emissions) or for use in industry (oil recovery, food processing or combination with hydrogen to produce synthetic fuels). Two main technologies were discussed to capture CO2 from the air via direct air capture: (i) in liquid based systems, air is passed through a chemical solution (e.g. a hydroxide solution), which chemically react with the CO2. For the recovery of CO2 (and the liquid for next absorption cycle), the system needs to use high-temperature heat while returning the cleaned air to the environment; (ii) in DAC based on solids, a solid filter binds the CO2 on the surfaces to separate it from the air. The recovery (release) of the CO2 from the filter is done by heating and/or using vacuum, depending on the choice of materials.