Why FRP Wins in Carbon Capture Projects

Carbon capture plants run some of the harshest chemical environments in industrial process design: wet CO2, hot amine solvents, and flue-gas condensate all attacking the same pipe rack, scrubber, and platform. Carbon steel corrodes fast in this service, and even 304/316 stainless steel suffers pitting and stress-corrosion cracking at weld seams and liquid-vapor interfaces.

Fiberglass-reinforced plastic (FRP) sidesteps the problem at the material level: it has no metal to corrode. That's why FRP grating, piping, and scrubbers already dominate the flue-gas desulfurization (FGD) industry — the closest existing analog to CO2 capture — and why capture-plant designers are specifying it for platforms, amine circulation lines, and absorber towers today.

The corrosion challenge is worse than it looks on paper

Post-combustion CO2 capture relies on amine solvents — typically MEA or MDEA — cycling between an absorber and a stripper, loaded and stripped of CO2 continuously. A 2025 review of absorber failures identifies four recurring damage mechanisms: under-deposit corrosion, pitting, erosion-corrosion, and chloride-assisted stress corrosion cracking in stainless steels (Journal of Failure Analysis and Prevention).

Carbon steel suffers accelerated wall thinning in this service. Stainless steel resists general corrosion better but stays vulnerable at liquid-vapor interfaces, weld seams, and wherever heat-stable salts and amine degradation products concentrate. The standard metallurgical fix — upgrading to duplex stainless or nickel-based alloys — solves the corrosion problem at a steep material and fabrication cost premium.

FRP avoids the mechanism entirely: without a metallic lattice, there's no electrochemical cell to drive pitting, no weld heat-affected zone to crack, and no alloy grade to keep upgrading.

FRP grating: safer footing, zero corrosion maintenance

Capture-plant platforms, walkways, and trench covers sit directly in the splash zone of amine mist and condensate. Steel grating in this service needs recoating or galvanizing touch-up on a recurring cycle; FRP grating doesn't corrode because there's no metal substrate to attack.

FRP grating also brings advantages steel can't match on a working platform:

1.       Non-conductive — removes an electrical hazard around instrumentation and control wiring

2.       10–30% lighter than steel (over 50% for plenum-type structures), cutting structural steel and crane requirements during construction (AMCA)

3.       Slip-resistant surface options that hold their grip even wet, unlike smooth or corroded metal

4.       No repainting or recoating cycle over a 25–50 year service life

FRP piping: built for amine and wet CO2 circulation

Amine circulation loops, wet CO2 duct runs, and caustic makeup lines are exactly the service FRP pipe was engineered for. A widely cited case at a 2,000 MW coal plant shows what happens with the alternative: rubber-lined carbon steel slurry piping across ten FGD absorber towers blistered, shed rubber fragments into spray nozzles, and let fluid permeate the lining to corrode the steel wall beneath it (RPS Composites case study).

The fix was FRP pipe in a fire-retardant vinyl ester resin — a product line with a track record across more than 150 FGD installations dating back to 1970. All ten towers were retrofitted, with an expected 20+ years of maintenance-free service.

The same case applies directly to carbon capture: no rubber lining to blister, no bare steel wall waiting behind a coating failure, and no scheduled re-lining outage.

FRP scrubbers and absorber vessels: the FGD playbook, applied to CO2

Wet scrubbing for SO2 removal (FGD) and wet absorption for CO2 removal are chemically close cousins — both are aqueous, both run acidic-to-basic gas/liquid contact at scale, and both attack bare carbon steel quickly. FRP absorber towers, desulfurization towers, and duct/chimney liners are already standard equipment across the FGD industry, supplied by specialist fabricators.

For carbon capture absorbers specifically, FRP construction offers:

1.       Chemical resistance to ammonia, chlorides, H2S, and acidic condensate without a coating system to fail (AMCA)

2.       Filament-wound and hand-laid fabrication that supports large-diameter, custom-geometry towers hard to shop-fabricate in alloy steel

3.       No weld seams in the wetted wall — removing the failure point where stainless steel absorbers most often crack

The lifecycle economics favor FRP

FRP's upfront cost sits between galvanized steel and stainless steel, but the total-cost picture flips over a plant's life. AMCA's cost model for corrosive-service fans put stainless roughly double the cost of FRP, and over a 30-year building lifecycle an FRP unit with zero replacement cost came in cheaper than galvanized steel, which needed mid-life replacement (AMCA).

Three factors drive that outcome for a carbon capture project specifically:

1.       No recoating, repainting, or re-lining outages over a 25–50 year service life

2.       10–30% weight savings on ductwork and piping (over 50% on large plenums), reducing structural steel, foundations, and crane costs during construction

3.       Fabrication flexibility that lets FRP components ship as large, complex, corrosion-proof sections rather than field-welded alloy assemblies

For an owner comparing capture-plant material specs, corrosion resistance isn't just a durability story — it removes an entire category of planned and unplanned maintenance outages from the operating budget.

The takeaway for project engineers and owners

Carbon capture plants inherit the same corrosive chemistry that has already pushed the FGD industry toward FRP for scrubbers, ducts, and pipe. The failure modes documented in amine absorbers — pitting, under-deposit corrosion, weld cracking — are electrochemical problems that only apply to metal. FRP grating, piping, and scrubber vessels remove that failure mode at the material level, at a lower installed and lifecycle cost than stainless steel or alloy upgrades.

For new capture builds and retrofits alike, specifying FRP for platforms, amine circulation piping, and absorber towers isn't just a corrosion-resistance choice — it's a maintenance-budget and schedule-risk choice too.