CO₂ liquefaction

The liquefaction of CO₂ is the process of converting gaseous carbon dioxide into its liquid form, a process that transforms it from an emission into a versatile and transportable resource. 

This step allows CO₂ to be stored, transported and efficiently used in various applications.

In addition, the purification and liquefaction of CO₂ plays a crucial role in carbon capture and storage initiatives, avoiding its release into the atmosphere in order to mitigate climate change. One more step towards decarbonization. 

The CO₂ liquefaction system designed by AB - DISCO₂VERY - allows purifying and liquefying the mixture composed mainly of carbon dioxide coming from the BIOCH4NGE® biomethane/RNG production system, in order to obtain liquid CO₂ suitable for food and industrial use.  

The CO₂ produced by the plant complies with European legislation (Regulation (EU) no. 231/2012 – Additive E290) and with the international standard ISBT (International Society of Beverage Technologists) for the use of carbon dioxide in beverages.

The plant is based on an integrated cryogenic process divided into 5 phases: 

1. Treatment: In the first part of the process, the purification system eliminates contaminants and odors through a system of activated carbon filters.

2. Compression: the gas is compressed to a pressure between 15 and 20 bar based on the customer's needs.

3. Drying: the moisture is reduced by condensation and absorption on molecular sieves.

4. Cryogenic distillation: the foreign gases (CH₄, N₂, O₂) present in the incoming mixture are separated from the carbon dioxide by means of cryogenic distillation technology, which makes it possible to obtain CO₂ with a content greater than 99.9% coming out of the system, as required by the ISBT standard. 

5. Storage: The bio-CO₂ is sent into a storage tank where it will be maintained at the desired pressure and temperature conditions.