CO2 capture

Postcombustion capture

Postcombustion capture consists in separating CO₂ from the other constituents of flue gases (water vapor, nitrogen, etc.). In this field, IFP Energies nouvelles is focusing its efforts on capture processes using chemical solvents. The cost reduction potential of these processes is significant and they can be deployed in existing power plants, provided their initial efficiency (without capture) is high enough, i.e. around 45%.

Chemical solvent processes

This technological avenue consists in adapting processes already developed by IFP Energies nouvelles for the deacidification of natural gas. For example, IFP Energies nouvelles has developed a first-generation process known as HiCapt, based on a high concentration MEA (monoethanolamine) solvent. The process represents a technological solution to the separation of CO₂ diluted in flue gases at low pressure produced by thermal power plants. The process can also be applied to CO₂ capture in gases emitted by cement works furnaces or blast furnaces in the steel industry. An optimized version of the process, using high-performance anti-degradation additives, will soon be tested on an industrial pilot with Enel, IFP Energies nouvelles's Italian partner.

Demixing solvents

A second research avenue being explored by IFP Energies nouvelles for postcombustion capture is aimed at identifying new solvents requiring less regeneration energy and that are compatible with environmental requirements. Research conducted in 2009 led to selection of a process based on demixing solvents, for which patents have been filed. This is a breakthrough process aimed at significantly reducing the cost of capture. With controlled demixing, only the amine that has reacted is sent to the generator, considerably reducing the heat required to regenerate it. Further savings are achieved by the regeneration of the amine under pressure, making it possible to reduce the energy costs associated with CO₂ compression.

Oxycombustion

Another CO₂ capture technology involves combustion in the presence of oxygen, or oxycombustion. In the absence of nitrogen, combustion products mainly consist of water and CO₂ and flue gases with a 90% CO₂ concentration can then be obtained by simple water condensation. But combustion in the presence of oxygen generates extremely high temperatures (up to 2,000°C) and is associated with hot spots if the operating conditions of the unit are not perfectly optimized. Within the framework of the ANR TACoMA project, coordinated by GDF Suez, IFP Energies nouvelles is developing a flameless internal-recycling oxycombustion pilot unit for the combustion of heavy fuels. The work will lead to the validation of computing tools to design an industrial unit.

Chemical Looping Combustion

IFP Energies nouvelles is also working on Chemical Looping Combustion (CLC) technology, which avoids the need to separate oxygen from air at an upstream stage – something which is particularly costly in terms of energy consumption. The oxygen is supplied via a metal oxide, alternately oxidized by air and reduced by the fuel, which is converted directly into CO₂ and water. In partnership with Total Gaz & Énergies Nouvelles, IFP Energies nouvelles has designed and constructed a CLC pilot unit, using its expertise in fluidized beds. The work will shortly lead to the design of a demonstration unit. In addition, bolstered by the results obtained within the framework of the ANR CLCmat project, IFP Energies nouvelles is actively working to identify and develop new metal oxides adapted to the CLC process, in partnership with major players in the materials sector.

The ability to produce oxygen cheaply for gasification or oxycombustion is a challenge that IFP Energies nouvelles is trying to overcome by developing a new rotary reactor concept using chemical adsorbents to separate oxygen from air. This work, launched in 2008 within the framework of the European Decarbit project, in partnership with Air Liquide and Sintef, will continue with the development of adsorbent materials.

Precombustion capture

IFP Energies nouvelles is researching new energy production processes, involving the production of syngas and hydrogen and integrating CO₂ capture. Precombustion capture consists in transforming hydrocarbons into syngas – a mixture of carbon monoxide (CO), hydrogen and water – before they are burned. Then, during a conversion process, the CO reacts with water to form CO₂ and additional hydrogen, which will subsequently be separated. The CO₂ can then be compressed and stored.

+ Industrial development > New energy technologies > CO₂
+ IFP Energies nouvelles and Europe > European CO₂ projects