In southern Indian industrial city of Tuticorin the air will be a bit cleaner from now on, as a local industrial plant has started capturing its own carbon dioxide (CO2) emissions and putting them to good use.
Tuticorin Alkali Chemicals has been producing soda ash (sodium carbonate) for decades. Now they’ve implemented a new carbon capture technology, allowing them to utilise CO2 emissions from their own coal-powered boiler as part of the manufacturing process.
The company is expected to scrub 60,000 tonnes of CO2 emissions annually, turning the pollutant into a commercially viable product. The sodium-based chemicals produced at the plant are widely used in glass manufacturing, household detergents, food and many other applications.
This development is one of the latest examples of carbon capture and utilisation (CCU), a commercially-focused approach that differs from the already established practice of carbon capture and storage (CCS), which typically means burying the carbon deep underground, often at great cost.
However, producing chemicals out of carbon emissions isn’t a groundbreaking practice either, says chemical engineering Professor Sandra Kentish from the University of Melbourne.
“There's nothing new or exciting in that, it's been around for decades,” says Kentish. “The novelty they're claiming is the solvent they're using.
“When you capture carbon dioxide using a standard approach, you use a solvent that ‘likes’ carbon dioxide, so the CO2 is absorbed into the solvent in a liquid state, and all the other gases escape into the atmosphere.”
The industry standard for scrubbing emissions in this way is a compound called monoethanolamine, but the Tuticorin plant is using a new process patented by Carbon Clean Solutions, a London-based firm started by two Indian chemists.
They have synthesised CDRMax, a solvent they claim does the job more efficiently, bonding with the CO2 molecules in the boiler chimney.
"So far the ideas for carbon capture have mostly looked at big projects, and the risk is so high they are very expensive to finance," Carbon Clean CEO Aniruddha Sharma told The Guardian.
"We want to set up small-scale plants that de-risk the technology by making it a completely normal commercial option."
Saving the planet?
“There's hundreds of people around the world at the moment trying to [create new processes], because if you can do carbon capture with less energy, it becomes more viable,” explains Kentish, adding that the commercial viability of CCU endeavours has been rather limited so far.
Hence Tuticorin has been making headlines, since the low cost of the new solvent enabled them to implement the carbon-scrubbing technology without government subsidies. The company claims their operations now have virtually zero emissions to air or water.
However, Kentish thinks that we likely won’t be saving the planet one chemical plant at a time, considering they make up only a tiny fraction of the total amount of carbon emissions.
"If you've got a baking soda business, and you want to make your baking soda business slightly more sustainable, it's a good angle. If you want to save the planet, it's not going to work," she says.