Absorption / Desorption

A Proven Technology for CO₂ Capture

After several years of research and evaluation of various CO₂ capture technologies, LAB has selected in cooperation with Brusche Process Technology the absorption/desorption process using a free amine-based solvent. To date, this is the most commercially viable and proven technology for large-scale post-combustion CARBON CAPTURE units.

During more than 10 years now, Brusche’s owners have build a small commercial CARBON CAPTURE plant for Waste To Energy, still in operation today which is the base of our common expertise and offer. This plant with more than 60.000 hours of operation has been operated and optimized to allow a safe and reliable production of liquid CO2 used in green houses.

Our CARBON CAPTURE solution is based on these choices and experiences. It uses MEA (Monoethanolamine), a solvent known for:

• Its industrial maturity and stability,
• Its availability on the market,
• Its license-free use, ensuring unrestricted accessibility,

Indeed, used for decades in several industries, MEA is currently the only solvent used in combustion post treatment Carbon Capture with solid references and a real return of experience allowing a safe design, construction and operation. In addition, a structured network of experts, laboratories, suppliers of equipment and advisors for this technology, allows a controlled development.

Faithfull to our DNA, we continue to explore other technologies and develop new solutions to always provide the best solution to our customers.

Flue Gas Pre-Treatment and Carbon Capture

Absorption / Desorption Process

The CO₂ capture process consists in a cyclic absorption–desorption–regeneration system, designed and engineered to efficiently separate and recover carbon dioxide from industrial flue gases. This process is widely used in post-combustion capture plants and relies on the reversible chemical interaction between CO₂ and a liquid solvent.

1. Flue Gas Conditioning:
Before entering the absorption unit, the flue gas is blowed into a Direct Contact Cooler (DCC) also named Quench/Condensor, where it is brought into contact with a cooling media, typically water. This step has two purposes: it removes residual particles and acid gases (such as SO₂ and HCl) that could degrade the solvent, and it reduces the gas temperature to the optimal range (typically 30–50 °C) for efficient CO₂ absorption.

2. Absorption:
In the Absorber column, the conditioned flue gas flows counter current to a descending liquid stream of chemical solvent, most commonly an aqueous amine solution. The CO₂ is removed from the gas phase by reacting with the solvent to form a liquid bonded compound, effectively removing it from the gas phase. The CO₂-rich solvent, also known as the "rich amine," is then pumped towards a cross/cross heat exchanger, where it is preheated by the regenerated solvent stream to improve overall energy efficiency before entering the Desorption unit.

3. Desorption:
The rich solvent enters into the Desorber (or Stripper), where it is heat regenerated, typically by a steam-driven reboiler, to reverse the chemical reaction and release high-purity CO₂ gas. This CO₂ gas exits the top of the Desorber column and is subsequently cooled and dried to remove residual moisture, preparing it for downstream Compression, Liquefaction, or Utilization.

4. Regeneration:
The lean solvent, now stripped of its CO₂ content, is pumped from the bottom of the Desorber column to the cross/cross heat exchanger to recover thermal energy before being cooled further to the appropriate absorption temperature before being recirculated back to the Absorber, completing the cycle. A proper regeneration ensures solvent stability, minimizes degradation, and maintains high capture efficiency over extended operational periods.