Climate change is one of the most critical challenges facing humanity today. Direct Air Capture (DAC) is presented as a promising technology to address this problem by capturing carbon dioxide (CO₂) directly from the environment.

This article explores in an initial way what Direct Air Capture is, how it works and its importance in the fight against climate change.

Chimney emitting smoke into the environment, representing the need for Direct Air Capture (DAC) technologies to reduce CO₂ emissions

Technology Description and Purpose

DAC is a gas abatement technology that could remove CO₂ and other greenhouse gases from the Earth's atmosphere on a large scale. In these proposals, carbon is stored underground through carbon capture and storage (CCS) or in products of varying duration, using carbon capture, use, and storage (CCUS) techniques.

Direct Air Capture (DAC) approaches use chemical reactions to separate CO₂ from the inlet air, using substances that act as a selective CO₂ filter. The two most developed processes are with liquid solvents and solid absorbents: the CO₂ is dissolved in a liquid solvent, for example a strong hydroxide solution, or it adheres to the surface of a solid absorbent, such as a plastic resin.

But, before continuing, what are CCS, CSS, PSC, CCUS, DAC and all these acronyms?

Although there are many acronyms, perhaps these are the main ones and the ones that should be clear:

  • According to the initial source of the captured CO₂:
  • According to the final destination of the captured CO₂:

  • PSC (Point Source Capture):

    In CO₂ terms, it refers to the capture of carbon dioxide (CO₂) directly from stationary, localized emission sources, such as power plants, factories, and other industrial facilities. These point sources emit large amounts of CO₂, and carbon capture technology is used to intercept the CO₂ before it is released into the atmosphere.

  • DAC (Direct Air Capture):

    This technology is designed to remove CO₂ directly from ambient air. Unlike other carbon capture methods, DAC can be deployed anywhere with access to renewable energy, making it extremely versatile. Companies like EDIBON are leading the way in the development of these innovative technologies.

  • DRC (Removal of Direct CO₂)

    : This is a term that refers to the direct removal of carbon dioxide (CO₂) from the atmosphere or from specific sources. This concept encompasses several technologies and methods designed to extract CO₂ from the air or other environments, in order to reduce concentrations of this greenhouse gas and mitigate climate change.

  • CCS (Carbon Capture and Storage):

    This technology is designed to capture carbon dioxide (CO₂) emitted by large industrial sources and power plants, preventing the CO₂ from being released into the atmosphere. Once captured, the CO₂ is stored in safe formations.

  • CSS (Carbon Sequestration and Storage):

    Similar to CCS, this technology focuses on capturing CO₂ and storing it in underground geological formations to prevent its release into the atmosphere.

  • CCUS (Carbon Capture, Utilization, and Storage):

    This technology not only captures CO₂, but also finds productive uses for the captured gas before storing it permanently. Uses may include the manufacture of building materials, synthetic fuels, chemicals, carbonated water, and many others.

Carbon Dioxide Capture Technologies and Methods: Our Experience

Point Source Capture, PSC

  • Method: Point Source Capture (PSC) uses post-combustion, pre-combustion, and oxy-fuel capture technologies to intercept CO₂ before it is released into the atmosphere.
  • Application: Commonly used in industries with high-volume, concentrated emissions, such as power plants burning coal or natural gas.
  • Advantages: High efficiency in high CO₂ environments; can be integrated into existing facilities.
  • Challenges: Requires specific infrastructure and can be expensive to implement and maintain.

Direct Air Capture, DAC

  • Method: Uses chemical reactions to separate CO₂ from the air, using liquid solvents or solid absorbents, and often uses large fans to move air through filters.
  • Application: Can be deployed anywhere with access to renewable energy, making it highly versatile.
  • Advantages: Not limited by the location of emission sources; can help reduce atmospheric CO₂ concentrations globally.
  • Challenges: Extremely expensive.
Continued research and development in these areas is crucial to moving towards a low-carbon economy and mitigating the effects of climate change by reducing or alleviating the challenges outlined above.

Driving Innovation in the Direct Air Capture (DAC) Value Chain

Clean air thanks to Direct Air Capture (DAC)

Direct Air Capture (DAC) technologies require a significant amount of energy. The two main DAC methods – solid DAC (S-DAC) and liquid DAC (L-DAC) – were initially designed to operate using both heat and electricity. S-DAC’s low-temperature heat requirements allow it to run on renewable energy sources such as heat pumps and geothermal energy. In contrast, L-DAC, which requires temperatures up to 900°C, typically relies on natural gas for heat. However, the CO₂ generated by the combustion of this gas is captured in the process, preventing emissions. Innovating to incorporate renewable energy options for high-temperature industrial heat would maximise the carbon removal potential of L-DAC plants.

The location flexibility of DAC plants needs to be demonstrated under different conditions. The theoretical advantage of DAC is its ability to be located anywhere with access to low-carbon energy and CO₂ storage or utilisation resources. It can also be located close to existing or planned CO₂ storage and transport infrastructure. However, there may be practical limits to this location flexibility. To date, DAC plants have operated successfully in a variety of climatic conditions in Europe and North America, but further testing is needed in locations characterised, for example, by extremely dry or humid climates, or polluted air.

Innovation in CO₂ use opportunities, including synthetic fuels, could reduce costs and provide a market for DAC. The first commercial efforts to develop synthetic aviation fuels using CO₂ captured from air and hydrogen have already begun, reflecting the important role these fuels could play, alongside biofuels, in the sector. Under the 2050 Net Zero Emissions Scenario, approximately one-third of aviation fuel demand in 2050 will be met by these synthetic fuels, but they may currently be more than five times more expensive than conventional fossil fuel-based options. More innovation is needed to support cost reduction and faster commercialization, thereby building a potentially large market for CO₂ captured from air.

Challenges and Considerations

Despite being such a promising technology, these challenges underline the need to continue researching and developing more efficient and economical methods.

At EDIBON, we are committed to furthering this research to improve the feasibility and effectiveness of DAC.

Our Leadership in Pilot Plants for CO₂ Capture

At EDIBON, we are pioneers in the design and construction of highly complex CO₂ capture pilot plants.From the very beginning, we have tackled and overcome the toughest challenges with ease, making a significant contribution to carbon dioxide removal.

We have developed and supplied pilot plants for the MOF4AIR project, an EU initiative for efficient CO₂ capture in industrial environments.

Some of our contributions include:

Combating climate change - EDIBON MOF4AIR PROJECT. TÜPRAS. Türkiye
Combating climate change - EDIBON MOF4AIR PROJECT. TCM. NORWAY
Solamat-Merex waste treatment center of the company Sarpi-Veolia

Tüpras Oil Refinery Company (Türkiye Petrol Rafinerileri A.Ş)

Testing centre for CO₂ capture technologies, Technology Centre Monsgtad (TCM)

Solamat-Merex waste treatment center of the company Sarpi-Veolia

Izmit, Turkey

Mongstad, Norway

Rognac, France

Benefits of the MOF4AIR Project

  • 95% reduction in carbon dioxide emissions from power plants and carbon-intensive industries.
  • 40% reduction in greenhouse gas emissions.
  • Rapid progress towards a low-carbon economy.
  • Employment of green technologies with ease of transport.