Linc Energy Reports Initial Success with Oxygen Enrichment in Underground Coal Gasification Process
27 May 2010
Linc Energy Limited successfully begun an oxygen air enrichment process at Chinchilla Underground Coal Gasification (UCG) project over the weekend. Linc reported a “step change” in the key quality gas measures within hours of commencing the oxygen enrichment process, including an increase in gas flow rates.
Oxygen enrichment of the air being injected into the UCG process is intended to ensure a better quality and purer syngas, said Linc Energy’s CEO Peter Bond. Oxygen injection also enables complete underground coal gasification in deeper coal seams more economically thereby opening up a significant number of coal opportunities around the globe.
The deeper the UCG process, the higher the pressure that is required to pump air or oxygen down the UCG injection well. Subsequently by enriching the air by the injection of oxygen, the result is lower nitrogen and lower compression costs.
—Peter Bond
Linc Energy has found that oxygen enriched air (being a mixture of oxygen and air which is being injected) is the most proficient, effective and economical way forward and that pure oxygen injection is simply not economical.
Linc Energy’s Chinchilla Demonstration Facility uses gas to liquids (GTL) technology to produce syncrude (which requires refinement to create diesel and other liquid fuel products) from the UCG syngas.
There are now quite cheap methods of producing relatively pure oxygen from the air. The nitrogen should be eliminated almost entirely, and CO2 captured from the refining process should be injected along with the oxygen in ratio around %50 percent. This process has been shown to recover more of the energy in the carbon fuel and will reduce the amount of oxygen needed. It might also free up the release of methane and other gases from the coal. Some of the CO2 might become liquid when it goes beyond the high heat zones and may dissolve some hydrocarbons to help them migrate to the reaction.
It is likely that coal can be better recovered by being dissolved and hydrogenated in a hydrocarbon liquid.
Fission reactors can provide the energy needed for separating the oxygen and the other processes in order to reduce the CO2 release from the production. The fission heat can also heat the oxygen and CO2 to waste less of the coal in producing heat. Fission heat is very cheap. Fission electricity is not so cheap but much cheaper than oil produced electricity. ..HG..
Posted by: Henry Gibson | 27 May 2010 at 01:59 PM
If they use fission energy as a heat source, they should not inject air but superheated steam as on oxidans. That would completely eliminate the nitrogen problem and produce more H2 per CO2 molecule. As long as any coal burning is done (hopefully not too long), this would decrease the CO2-intensity greatly.
Posted by: Alain | 31 May 2010 at 09:22 AM