The Swiss company CO₂ Energy AG has commissioned Hitachi Zosen Inova to construct an installation to separate and liquefy renewable carbon dioxide at an existing biogas plant in Nesselnbach (Canton Aargau), Switzerland. The plant at the site has until now produced biogas, which is upgraded into biomethane for feeding into the regional natural gas grid. In the future the new installation will capture and liquefy the CO2 from the gas upgrading process for use as product gas in various industrial applications, for example as technical welding gas, in gas extinguishing systems or for inertisation. The HZI liquefaction plant will have a processing capacity of 4,000 t/a CO2. In addition to the efficient utilisation of carbon dioxide, the project contributes to the substitution of fossil CO2.
HZI is developing the plant as a compact, container construction that will liquefy the high-purity product gas and inject it into storage tanks. Upgrading existing biogas plants with CO2 liquefaction is a pioneering project for plant operators that also pays off monetarily by serving other sectors of the economy, making it fully circular.