In Switzerland, municipal energy and waste management companies, Regionalwerke AG Baden (RWB) and Recycling Energie AG, held an official opening ceremony for a carbon dioxide liquefaction facility in Nesselnbach, Canton Aargau. The plant was developed by compatriot cleantech providers Hitachi Zosen Inova AG (HZI) as a turnkey delivery on behalf of the operating company CO2 Energie AG.
Held on July 4, 2023, the official inauguration of the Nesselnbach liquefaction facility saw invited guests from politics and business witness an example of best practices in terms of optimizing circularity and maximizing the recycling of resources.
Carbon dioxide (CO2) from the upgrading of biogas into biomethane (aka renewable natural gas – RNG) that was previously released into the atmosphere is now used in industrial applications, for example in processes in the pharmaceutical, medical, and food industries.
Existing concept evolved
The Recycling Energie site in Nesselnbach includes a biogas plant from which the raw biogas has been refined by RWB since 2018 to produce biomethane (RNG) for injection into the gas grid.
The upgrading process involves separating carbon dioxide (CO2) and methane (CH4), the two main components of raw biogas.
The biomethane is fed into the existing grid infrastructure for distributed use in heat and power generation, whereas the CO2 bound in the biogenic substrates and separated in the gas treatment process, is usually released into the atmosphere.
By expanding the plant, a very complex undertaking from a technical point of view, CO2 Energie now makes it possible to use this by-product. It’s fed from the gas upgrading plant to the liquefaction unit where it is purified, filtered, and dehydrated in several sub-steps. The gas is liquefied by cooling it to minus 24 degrees Celsius. This allows it to be compressed into tanks for storage and transport, explained Philippe Lehman, CEO of CO2 Energie during the opening ceremony.
The CO2 needed in numerous applications can thus be provided from renewable sources. This reduces the use of fossil-derived CO2 and promotes decarbonization.
Effective project partnership
CO2 Energie commissioned HZI to deliver this project in Nesselnbach at the end of 2021. Thanks to an extensive portfolio of green-gas-related technologies within the group, the green tech company was an accomplished project partner with the ability to coordinate all the work involved in the process.
We’re delighted to be able to celebrate the unveiling of this pioneering climate protection project with our client today. Hopefully, concepts of this kind will set a precedent and drive decarbonization forward, said Dr Benoît Boulinguiez, Managing Director of one of the German HZI companies in charge of developing and producing the CO2 liquefaction facility.
The plant, which is of modular container construction with two scrubbing towers, almost completely recycles the carbon dioxide produced: up to 3,000 tonnes per year.
It was manufactured at the HZI site in Zeven, northern Germany, where most of HZI’s gas upgrading and liquefaction teams work.
