In-situ methane enrichment

In-situ methane enrichment is a method to upgrade biogas that has the potential to become more cost effective than existing, comerically available, technologies. The principle is that sludge from the digestion chamber is circulated through a desorption colon and back again. Desorptionen of carbon dioxide is accomplished by letting the air bubble through the colon. The process utilizes the fact that carbon dioxides is easier to solve in water than methane is.

The technology is developing through a number of projects:

• In 2010-2011 modelling and simulations were used to investigate the conditions for upgrading biogas from anaerobic digestion of sewage sludge to vehicle fuel quality using in-situ methane enrichment.
• In 2014 pilot scale trials at Lövsta biogas plant will take place, as part of the SE Biomethane project, which is financed by the Swedish Energy Agency through EN ERA-NET Bioenergy.