AirMyne, an American cleantech startup founded in 2022, has developed direct air capture (DAC) technology that directly removes atmospheric CO₂. Their innovative approach employs a specialized liquid capture agent and a low-temperature thermal regeneration process. AirMyne's DAC technology is designed to be scalable and energy-efficient, which helps to reduce overall costs associated with direct air capture.
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Challenges: carbon emissions
Since the early 1900s, atmospheric carbon dioxide (CO₂) levels have surged by 50% due to human activities, primarily the combustion of fossil fuels for energy production, transportation, and industrial processes. This excess CO₂ acts as a greenhouse gas, trapping heat and causing air and ocean temperatures to rise. The resulting warming effect has elevated the global average temperature by approximately 1.1 ºC since the pre-industrial period.
This increase of the global average temperature has led to a cascade of environmental impacts, including more frequent and intense extreme weather events, melting polar ice caps and glaciers, rising sea levels, shifts in species ranges, increased risk of species extinction, challenges to agriculture and food security, and ocean acidification.
To address these pressing issues, the Paris Agreement aims to limit global warming to well below 2 ºC above pre-industrial levels.
The Intergovernmental Panel on Climate Change (IPCC) has calculated a critical "carbon budget" to address global warming. This budget, estimated at roughly 500 gigatons (GT) of CO₂, represents the maximum amount of CO₂ that can be emitted while maintaining a 66% probability of limiting global temperature rise to 1.5 ºC above pre-industrial levels.
At current emission rates, this budget would be exhausted in approximately a decade, highlighting the pressing need for swift and significant reductions in CO₂ emissions. This stark timeline emphasizes the urgency of implementing immediate and comprehensive measures to curb greenhouse gas emissions across all sectors of the global economy.
AirMyne Technology
Direct Air Capture (DAC) is a technology that employs large-scale installations equipped with specialized filters or sorbents to extract CO₂ directly from the atmosphere. Once captured, CO₂ is isolated and can be either stored underground or utilized as a climate-neutral raw material for various applications.
DAC faces significant challenges due to its high energy requirements and associated costs. The process is inherently energy-intensive because of the low concentration of CO₂ in the atmosphere (about 0.04%), necessitating continuous air movement through capture agents. Furthermore, many DAC technologies rely on capture agents such as CaO or liquid chemicals that typically demand high temperatures to release pure CO₂ and regenerate the agent. These factors contribute to the current high costs of DAC, which range from $250 to $600 per ton of CO₂ equivalent, impeding the rapid and widespread deployment of DAC systems.
AirMyne has innovated a low-temperature DAC technology utilizing a specialized alkaline capture solution. This novel approach, combined with advanced air-liquid contact materials, enables efficient CO₂ extraction from the atmosphere using a minimal volume of capture solution.
The CO₂-rich solution undergoes thermal processing at temperatures below 150°C, releasing pure CO₂ and regenerating the alkaline capture agent. This low-temperature process can leverage waste heat, geothermal energy, or other low-grade heat sources.
AirMyne's DAC method stands out for its scalability and reduced energy consumption, effectively addressing the cost barriers that have historically hindered the widespread deployment of DAC systems.
AirMyne DAC system
The diagram below depicts AirMyne’s DAC system, which uses an air-liquid contactor and a stripping column to capture CO₂ from the air.