Chemical-kinetic process analysis for combustion in CO₂ atmosphere with special reference to CO₂ sequestration

Process diagram for simulating kinetic variables of combustion in a CO<sub>2</sub> atmosphere.

Process diagram for simulating kinetic variables of combustion in a CO₂ atmosphere.

Oxyfuel combustion is a new concept in power plant technology. The fuel is converted with pure oxygen in a carbon dioxide atmosphere in the absence of nitrogen. Ideally, only water and carbon dioxide are produced, which can then be condensed and sequestrated, respectively. The sequestrated CO₂ is then liquefied and can be injected into oil or natural gas reservoirs to enhance oil and natural gas recovery. Countries without this option may consider storage in former coal mines, where the CO₂ can mineralise over several thousand years. The additional energy required by this technology, compared to conventional power plants, is estimated at about 20 to 30%, plus the costs for transportation to the CO₂ deposit sites. These costs can vary considerably.

In order to simulate the kinetic variables for combustion in a CO₂ atmosphere (“oxyfuel combustion”), a simplified process diagram involving a combination of reactors is installed in the chemical kinetics group (see Fig. 1). The effects of fuel properties, recirculation rates, etc. on the formation of CO, NO_x or on other process variables can now be simulated using detailed validated reaction mechanisms, in order to show the correlations between kinetically controlled parameters.

Chemical-kinetic process analysis for combustion in CO2 atmosphere with special reference to CO2 sequestration

Chemical-kinetic process analysis for combustion in CO₂ atmosphere with special reference to CO₂ sequestration