Biogas is a carbon neutral alternative to fossil fuels that can replace natural gas and be used to produce electricity. Unfortunately, the decomposition process that comes along after biogas is used as a fuel creates a number of nasty chemicals and can be costly to dispose of properly.
Enter Andrew White, a chemical engineer from Canada, who has developed a system to neutralize the chemical waste produced while using biogas as fuel. Not only does it eliminate the waste, it actually turns it into something useful: fertilizer.
Biogas makes use of methane, and one of the best side effects is that it keeps that methane from reaching the atmosphere, where it is far worse for the climate than carbon dioxide. About 22 times as bad, actually.
So biogas helps keep methane down, but the bacteria which produce biogas also produce hydrogen sulfide, which is toxic. The trick to using biogas is getting the hydrogen sulfide out, which White’s process does by converting that hydrogen sulfide into sulfur. We’ve been using sulfur as a fertilizer for quite some time now, and its safe to use as such.
Called SulfaCHAR, the product is produced at a University of Toronto research spin-off called CHAR Technologies, which recently received a grant from the Canadian government. So far, production is small, but it’s already being put to use to clean biogas and produce fertilizer.
With the help of the grant, $750,000 CAD (about $570,000 USD), SulfaCHAR will be able to ramp up production to about a ton per day by next spring. A year after they should be able to produce about 10 tons per day, which would be enough to serve 100 renewable gas plants.
Products like SulfaCHAR are going to be increasingly important over the next century or so, as we struggle to reduce or, if possible, reverse the effects of climate change on the Earth.