A team of engineers has developed a new kind of wastewater treatment that manages to capture CO2 and produce energy at the same time as cleaning water.
The new system has been built by researchers from the University of Colorado Boulder. Called Microbial Electrolytic Carbon Capture (MECC), it exploits an electrochemical reaction to clean water — but it also absorbs more CO2 than it releases,whilst creating hydrogen gas that can be used as a fuel. The work is published in the journal Environmental Science and Technology.
The technique takes advantage of salts present in wastewater to instigate electrochemical reactions that see CO2 combine with impurities in the water, forming stable mineral carbonates and bicarbonates. Those products can actually be used too, according to the researchers, as raw materials in the construction industry. Most wastewater treatment systems actually contribute to CO2 emissions, both through the use of energy and the decomposition of organic materials used in the process.
Sadly, the system only works at a very small scale so far — so this is at best a proof-of-concept. Now, the researchers are working to make the system work more efficiently, in the hope that it can be scaled up to work at an industrial size.
Image by Andrew Stawarz under Creative Commons license.