Fluor's Econamine FG Plus technology is a carbon dioxide (CO2) recovery process specially designed to capture CO2 from low-pressure, oxygen-containing streams. Fluor's solvent formulation and advanced reclaiming techniques allow the technology to work in an environment where most other processes would fail, such as on boiler and reformer stack gas and gas-turbine flue-gas streams.
The CO2 recovered by the Econamine FG Plus process can be tailored to meet the end user's specifications. The CO2 can be compressed for use within a chemical plant, liquefied for transport, made supercritical for enhanced oil recovery (EOR) applications, or purified for use in the food and beverage industry.
- Econamine FG Plus is an amine-based technology for large-scale, post-combustion CO2 capture.
- It is the first, most widely applied process with extensive proven operating experience in the removal of carbon dioxide from high oxygen content flue gases, up to 20% volume.
- Performance has been successfully demonstrated on a commercial scale over the past 20 years.
A typical Econamine FG Plus process is described in the flowsheet on the Power Plant Applications page Power Plant Applications page.
- Specifically designed for removal of CO2 from low-pressure, oxygen-containing, flue-gas streams
- Pilot tested on a coal based fluegas
- The only process with extensive proven operating experience in the removal of CO2 from:
- High oxygen content flue gases (up to 15% by volume)
- Low CO2 content flue gases (as low as 3.1% by volume)
- Gas turbine exhaust gas (pressure sensitive source)
- Twenty years of experience with twenty-five commercial installations
- Licensed process around the world
- No custom-manufactured or expensive solvent
- The main ingredient of the solvent is readily available worldwide
Fluor has commercial plant experience removing carbon dioxide from dilute sources. Twenty four units have been licensed so far. Econamine FG Plus is the only technology in the world that has been commercially proven in CO2 recovery from gas-turbine exhaust.
This experience is with a natural gas fired power plant in Bellingham, Massachusetts, owned by Florida Power & Light, running 365 short tons of CO2 per day, recovered from the exhaust. The Econamine FGSM plant was designed and constructed by Fluor and was maintained in continuous operation from 1991 to 2005. Due to increased natural gas prices in 2004 to 2005, the power plant operated in a peak load shaving mode which rendered the CO2 capture plant uneconomical.
This unique gas turbine flue-gas experience is notable for:
- Low CO2 concentration in flue gas – 3.1% by volume
- High oxygen concentration in flue gas – 13.5% by volume
- Pressure sensitive source: back pressure or pressure fluctuation in flue-gas line is not tolerated
- Demonstrated 100% air-cooling
No other vendor has long-term commercial operation experience with CO2 recovery from flue gas with very a high oxygen concentration.
Fluor's experience gained from the design, construction, and 14 years of operation of the Bellingham facility has led to innovative strategies to prevent amine degradation and corrosion, advancements that translate to improved reliability, and cost-effective design and operation of future Econamine FG Plus plants.
Although technologies available today capture most pollutants released from coal-based power plants, there are still residual quantities (SO2, H2SO4, NOx, ammonia, particulates, and other trace constituents) remaining in the flue gas. Carbon capture systems remove the majority of these pollutants, but the pollutants increase complexity and operating costs of these systems, regardless of the carbon-capture technology.
In any amine system, impurities in the flue gas lead to the formation of heat stable salts (HSS). HSS, the product of acid-base reactions between amines and various acidic species, must be converted back into amine through a reclaiming process.
Reducing flue-gas impurities to very low levels upstream of the absorber is more cost-effective and is part of Fluor's process design strategy for coal-fired power plants.
Every CO2 removal application has unique site requirements, flue gas conditions, and operations parameters.
To optimize the CO2 removal for a specific plant, Econamine FG Plus has multiple advanced features that can be selected for a customized plant design.
These features include:
- Advanced solvent formulation
- Absorber intercooling
- Lean vapor compression configuration
- Advanced reclaiming technologies
- Lean Vapor Compressor (proprietary concept)
- Heat integration with the power plant
The Econamine FG Plus process produces two types of emissions/effluents:
- Absorber stack emission
- Reclaimer wastewater
Absorber stack emissions
Typically, the absorber stack emission is essentially the same as the source stack, except for the absorbed CO2, SOx, and a portion on the NOx.
Also, a trace quantity of solvent is emitted from the absorber, due to vapor pressure loss and mechanical carryover, and a small amount of ammonia is formed by the oxidation of solvent, due to the oxygen present in the flue gas. The ammonia is stripped from the liquid phase by the flue gas as it flows through the absorber and is vented to the atmosphere.
Fluor has aggressively pursued strategies for minimizing ammonia formation and reducing the solvent loss in the vent by washing the treated flue gas in advanced column internals. Recently, Fluor has developed several low pressure drop scrubbing systems to lower the solvent emissions to very low levels.
Fluor's advanced reclaiming technology significantly reduces reclaimer waste.
The Econamine FG Plus process recovers combustion water that can be reused in the power plant. The combustion water is of good quality and can be used as a feed stream to the demineralization plant, or within the process itself after minimal treatment.
Large-scale CO2 sequestration projects require multiple CO2 absorption trains, resulting in large plot areas. Smaller CO2 capture retrofit applications may find plot availability plays a vital role in the feasibility of the project.
Fluor has focused on strategies to minimize the footprints of Econamine FG Plus plants.
These strategies include:
- Large diameter absorber design
- Plate and frame exchanger train minimization
- Reboiler shell count minimization
Large diameter absorber design
For large-scale CO2 capture applications, Fluor has developed absorbers designs with diameters of up to 60 feet, to minimize the number of absorption trains. Fluor has experience with the design and construction of columns with diameters of 40 to 50 feet.
Plate and frame exchanger train minimization
Fluor has pioneered the use of plate exchangers for thermal efficiency and plot size minimization. Plate exchangers for large CO2 capture units are usually applied in multiple trains and require considerable plot space.
Plate size can be increased and/or the plate efficiency can be improved to minimize the number of parallel exchanger trains.
Reboiler shell count minimization
For large-scale applications, Fluor has developed a unique reboiler design to minimize the number of shells, reducing the plot space and simplifying design and operating complexity.
Fluor has built and commissioned reboilers (in refinery service) similar in size to those required for CO2 capture in 1,000-MW coal-fired power plants.