The business turning sewage sludge into fuel
French company Cyro Pur converts biogas into ‘pipeline quality ’liquefied natural gas
When anaerobic digestion takes place, organic materials – think food waste – are broken down by microorganisms in an oxygen free environment, producing biogas.
Described by the U.S. Department of Energy as a proven energy source both in the U.S. and around the world, biogas can in turn be processed, purified and turned into biomethane.
The DOE describes biomethane as being “pipeline-quality” and “fully interchangeable with conventional natural gas.”
In France, one company has been looking to turn biogas into liquefied natural gas (LNG), or bio-LNG. Cryo Pur says its system generates bio-LNG with a high energy efficiency.
Cryo Pur’s process works in three steps. The first step involves the removal of hydrogen sulphide, water and pollutants. The second sees the biogas cooled to minus 120 degrees Celsius, with the separation and liquefaction of CO2 taking place.
The resulting biomethane is then compressed to 15 bar and liquefied at minus 120 degrees Celsius, with the bio-LNG then stored in “cryogenic vessels.”
“The process developed by Cryo Pur is especially done to convert biogas into biomethane, and the biomethane that we produce today… has exactly the same quality as natural gas, so it’s a good result,” Pierre Coursan, biomethane market manager at Suez, told CNBC’s Sustainable Energy. Suez is one of Cryo Pur’s commercial partners.