CO₂ recovery and liquefaction systems for biogas upgrading
Solveno Technologies’ CO₂ recovery and liquefaction systems process CO₂-rich off-gas from biogas upgrading into purified liquid CO₂. Our modular CB range combines compression, gas treatment, refrigeration and distillation, with the configuration selected for the available gas and required product specification. Compare the models and options below, or explore the application of CO₂ recovery at biomethane plants.
How CO₂ recovery and liquefaction work
The process includes compression, gas purification and drying, followed by cooling and liquefaction. Distillation separates remaining volatile impurities from the liquid CO₂. Treatment steps are selected according to the inlet gas analysis and required product quality. A methane-containing stream may be returned to a suitable point in the upgrading process where the configuration allows; other non-condensable gases require an appropriate removal route. Food-grade supply also requires source qualification, compliance with individual impurity limits and quality verification.
Standard CO₂ recovery and liquefaction systems
Our standard models cover a range from 350 to 4,500 kg of CO₂ per hour. We also provide project-specific configurations for different gas conditions and output requirements. The modular, containerized design supports site integration and automated operation. The operating range and required utilities are defined for each project.
Shown below are two standard configurations: the CB-17, capable of processing up to 1,750 kg/h, and the CB-12, with a processing capacity of up to 1,250 kg/h. Model selection depends on minimum, normal and maximum gas flow, CO₂ concentration, inlet pressure, ambient conditions and required liquid CO₂ quality.
CB-17 | CB-12 | |
|---|---|---|
 |  | |
Capacity | Up to 850 Nm³/h | Up to 600 Nm³/h |
| End product | Liquid CO₂ | Liquid CO₂ |
| CO₂ purity** | >99.9% | >99.9% |
Footprint* | 9 m × 8.5 m | 12.5 m × 8.5 m |
| Electricity consumption | Specified for the project conditions | Specified for the project conditions |
| Refrigerant | CO₂ in a closed circuit | CO₂ in a closed circuit |
| Application | CO₂-rich off-gas from biogas upgrading | CO₂-rich off-gas from biogas upgrading |
* The final site layout is confirmed during engineering.
** Bulk purity alone does not establish food-grade suitability. Individual impurity limits, source qualification and quality procedures also apply.
Comparing performance: Assess electricity per tonne of saleable liquid CO₂ together with recovery yield, at the same inlet composition, pressure, ambient conditions and operating load. Define whether compression, purification, refrigeration and auxiliaries are included. Our FAQ explains how to compare energy consumption and CO₂ recovery yield.
Download the CB-17 product sheet for further technical information:
Download the CB-12 product sheet for further technical information:
Project-specific configuration
Solveno’s engineering services assess the available gas, required output, utilities and integration constraints to select the suitable recovery and liquefaction configuration. The proposal should define the supply boundaries, site works, storage interfaces and agreed performance conditions.
Key benefits
The CB range is designed for downstream CO₂ recovery at biomethane plants. The following features are assessed against the requirements of each project.
- Designed for biogas upgrading: Treats the CO₂-rich off-gas separated during biomethane production.
- Residual methane recovery: Enables assessment of a methane return route, subject to gas composition and integration with the upgrader.
- Modular installation: Containerized equipment, with utilities, foundations, access and connections defined during engineering.
- CO₂ utilisation and carbon intensity: Provides liquid CO₂ for suitable outlets. Any recognised CI improvement depends on the applicable methodology, CO₂ destination and additional emissions.
- Additional product value: Creates opportunities for liquid CO₂ sales or on-site use where quality, demand and logistics support the business case.
- Defined product quality: Purification is selected for the agreed impurity limits and end use, including food applications where the required qualification and controls are in place.
Optional equipment and supply scope
The options below can complement the recovery unit. The quotation defines which equipment, installation works and services are included. Storage, loading, quality monitoring and energy integration should be selected according to the production profile and intended CO₂ outlet.
Liquid CO₂ storage
Solveno Technologies can supply one or more liquid CO₂ storage tanks, with engineering, procurement and construction included in the agreed scope. Storage capacity is selected according to production, collection frequency or on-site use, and the required operating buffer. Design conditions and applicable certification requirements are defined for the project.
CO₂ quality analyser
An automated CO₂ analysis system can be integrated for product quality monitoring. The components measured, detection limits, sampling points and analysis frequency are selected against the required specification. Calibration and sampling arrangements form part of the quality control plan. An analyser verifies the parameters it measures; it does not replace source qualification or the overall food-grade quality system.
Truck loading station
Solveno Technologies can supply a truck loading station for distribution of the liquid CO₂ product. Engineering, procurement and construction can be included in the agreed scope. The design must align with storage conditions, collection vehicles, transfer requirements and site safety arrangements.
CO₂ measurement and reporting package
Calibrated flow measurements can support a CO₂ mass balance and reporting of recovered quantities. Measurement points and reporting boundaries are defined for the installation. Tonnes recovered are not automatically tonnes of CO₂-equivalent emissions avoided. Climate reporting also depends on the baseline, energy use, methane emissions, CO₂ destination and applicable methodology. See our FAQ on carbon intensity and CO₂ recovery.
Energy integration
Heat recovery and integration with available site utilities can be assessed during engineering. Their value depends on temperature levels, the timing of heat demand and the additional equipment required. Any benefit is evaluated against the complete energy balance and operating costs of the project.
Select the right CO₂ liquefaction system
Send your plant location, gas analysis, minimum and maximum flow, inlet pressure and temperature, annual operating hours and required product quality. Include the intended outlet and available utilities where known. Solveno can use these inputs to assess model selection, treatment requirements and integration scope.
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