Harnessing greenhouse gases from point sources, such as flue stacks, is an accepted mitigation for air pollution. However, capturing carbon dioxide directly from the atmosphere has been debatable in terms of its efficiency in reducing carbon footprint.
A Swiss company, Climeworks, has just initiated such effort that could prove its effectivity in reducing carbon build-up by establishing the world’s first commercial plant to capture carbon dioxide directly from ambient air. “Highly scalable negative emission technologies are crucial if we are to stay below the 2-degree target [for global temperature rise] of the international community,” says Climeworks co-founder Christoph Gebald.
The facility operates with 18 large blowers that suck in ambient air, which is then filtered. In order to capture its carbon dioxide, it will undergo adsorption and desorption processes. During adsorption, carbon dioxide is scrubbed or collected from the incoming air by adsorbing it into a solvent such as water. To separate the carbon dioxide from the solvent or water, the output of adsorption will undergo desorption. This concentrated carbon dioxide then goes to its greenhouse farm or in tanks to sell them to customers, such as carbonated drinks industry. Meanwhile, the cleaner air or carbon-less air goes back to the atmosphere.
Aside from sucking air, the large blowers also function as heat absorbers to an incineration process of a nearby municipal waste disposal company. The heat absorbed is used to dry up saturated filters, rendering them useful again for a few thousand times.
Although the capacity of the pilot plant is not yet that large, about 900 tons yearly, which is equivalent to emissions from 200 cars, the current facility could be the first step to Climework’s goal of capturing one percent of global carbon emissions in eight years. The company acknowledges though, that in order to do so, it has to build 250,000 similar plants.