We ain’t unaware of the climate change and its impact on our planet. Not the sole but chief responsible cause for global warming is the excess production of carbon dioxide (CO2). Along with CO2 other greenhouse gases also filling the atmosphere and pace up the warming of the planet ‘Earth’.
Since 1951, the surface temperature of the earth is being risen relentlessly. It has risen by 0.8 degrees C. Therefore, it is now necessary to put right this issue, in the same manner, it has been deteriorated.
Currently, the scientists are using the Direct Air Capture (DAC) method to sequester the atmospheric carbon dioxide which will not impact global warming further. This method is amongst the number of still theoretical techniques to suck CO2 directly from the air and turn it into a form which is harmless.
There is a technique Bio-energy with carbon capture and storage (BECCS) already in use and the most researched one to date. It is being utilized at the industrial scale. Whereas the new technique, DAC, is the frontrunner in this race.
How does this technique work?
DACs can capture carbon at more diverse and distributed sources. No matter roughly half of annual CO2 emissions come from distributed sources (such as vehicle tailpipes).
DACs generally operate by pushing air past a sorbent chemical which binds with carbon dioxide but allows other molecules to pass unimpeded. For example, one of the earliest sorbents employed was a calcium hydroxide solution, which strongly binds with CO2 to create calcium carbonate. The captured CO2 is then unbound from the sorbent, purified and concentrated for use in industrial applications.
With the calcium carbonate method (which is derived from the Kraft process), the material must be separated from the solution, dried, and then carbonized at 700 degrees C.
Professor Chris Field, former co-chair of the Intergovernmental Panel on Climate Change’s (IPCC), and Dr. Katharine Mach, director of the Stanford Environment Facility, wrote in a 2017 Science article, “Direct air capture could become a major industry if the technology matures and prices drop dramatically,”
“Direct air capture might require much less land but entail much higher costs and consumption of a large fraction of global energy production.”
The Healthy Climate Alliance unveiled a prototype DAC at the Global Climate Action Summit on Tuesday.