Specialist engineering · Carbon capture
Carbon capture engineering using VPSA
We help industrial operators assess, design and deliver CO₂ capture based on vacuum pressure swing adsorption (VPSA), a solvent-free way to separate CO₂ from flue and process gases.
- Feed gas in cooled and dried, then blown to the beds
- Beds swap roles one adsorbs while the other regenerates
- Vacuum pump draws off a CO₂-rich product
- Lean gas vented mostly nitrogen
- CO₂ to storage or use after conditioning and compression
01How VPSA works
Two beds, one rhythm
VPSA uses beds of solid adsorbent that hold on to CO₂ more strongly than the other gases in the stream.
01
Adsorb
The gas is fed through an adsorbent bed at close to atmospheric pressure. CO₂ is held on the adsorbent, and the CO₂-lean gas (mostly nitrogen) passes through and is vented.
02
Evacuate
When the bed is loaded, a vacuum pump lowers its pressure and draws off a CO₂-rich product stream.
03
Regenerate and repeat
The bed is re-pressurised and returns to adsorption. Several beds run in sequence for continuous operation. Two-stage arrangements are used where higher CO₂ purity is needed.
02Applications
Where VPSA can fit
Industrial point sources
Flue and process gases from sites such as cement and lime, refining and chemicals.
Process off-gases
Streams with moderate to high CO₂ concentrations, for example from reforming and other chemical processes.
Biogas and gas upgrading
Removing CO₂ to upgrade biogas or other gas streams.
Retrofit and modular projects
Phased or smaller-scale capture where a compact, modular plant suits the site.
03Choosing a route
Weighing VPSA against other capture routes
Advantages
- No liquid solvent to handle, degrade or emit.
- Regenerated by changing pressure rather than with steam heat.
- Modular, with fast start-up and shutdown.
Things to engineer for
- Gas pre-treatment: moisture and impurities such as SOx and NOx affect many adsorbents.
- The balance between CO₂ purity, recovery and energy use.
- Vacuum and compression energy, which drive operating cost.
We give you an objective comparison with solvent-based and other capture technologies, so the choice suits your gas, your site and your budget.
04Our services
Carbon capture services
01
Feasibility and screening
Gas characterisation, capture targets and an early view of technical and economic viability.
02
Process design and simulation
Adsorbent selection, cycle design, bed sizing, and mass and energy balances.
03
Techno-economic assessment
Capital and operating costs, energy per tonne of CO₂ and cost of capture, with sensitivities.
04
Integration engineering
Tie-ins with your existing plant and utilities, plus CO₂ conditioning and compression for transport or use.
05
Pilot and vendor support
Test programme planning, vendor and technology evaluation, and technical due diligence.
06
Project management
Planning, risk and stakeholder management from concept through to commissioning.
05How we work
From your gas stream to a working plant
01
Assess
Your gas streams, emissions and site constraints.
02
Design
The capture concept and how it integrates, with costs.
03
Deliver
Engineering, procurement and construction support.
04
Improve
Performance after start-up.
Related technical study
Planning a carbon capture project?
Tell us about your gas stream and goals, and we’ll help you find the right route.