Methods for treating gaseous exhaust

Abstract

There is provided a method of combustion within an internal combustion engine. The method includes supplying a oxidant-comprising gaseous material to a combustion zone and contacting the oxidant-comprising gaseous material with a fuel within the combustion zone, with effect that gaseous combustion product material is produced. The method further includes recycling post-combustion material, which is derived from the combustion product material, such that the supplied oxidant-comprising gaseous material includes a portion of the recycled post-combustion material. The oxidant-comprising gaseous material is enriched in diatomic oxygen relative to atmospheric air. The method may also include fractionating a CO2-recovery ready gaseous material that is derived from the gaseous combustion product material, into at least a liquid carbon dioxide-rich product and a diatomic oxygen-comprising gaseous material. The method may also include recycling this diatomic oxygen-comprising gaseous material, derived from the diatomic oxygen-comprising gaseous material, such that the supplied oxidant- comprising gaseous material includes the recycled recovered diatomic oxygen- comprising gaseous material.

Description

METHODS FOR TREATING GASEOUS EXHAUSTFIELD

[0001] This relates to combustion methods, and in particular, combustion methods for improving the performance of carbon sequestration processes.BACKGROUND

[0002] The range of CO2 concentration in most exhaust gas streams from the combustion of hydrocarbon fuels is typically from about 0.5% to about 20%. At such low concentrations, the CO2 cannot be condensed from these mixtures at easily accessible pressures and temperatures, nor will the compressed gas mixture be easily or cheaply transported. Separating the CO2 from this combustion product gas mixture can be difficult and often requires the implementation of a chemical based absorption (liquid based) or adsorption (solid based) CO2 capture process. The CO2 must be selectively reacted, for example using liquid absorption, solid adsorption, or membranes, while the other gases (often N2, H2O, and the remaining O2) remain untouched. Once absorbed into solution (or adsorbed to a solid), the CO2 must then be stripped from the medium so it can be handled in its pure form. The CO2 then gets compressed and / or liquified for transportation. The integrated process has several sub-processes working together, all of which have multiple constraints, including lifetime limitations, energy demands, size restrictions, capital costs, areal plant footprints, etc.

[0003] A third type of CO2 separation process exists whereby CO2 is separated from other gases by employing "physical" rather than "chemical" separation technologies. Physical CO2 separation technologies exploit the high CO2 condensation temperature relative to gases such as nitrogen and oxygen. CO2 can be condensed into a liquid if it has a high enough partial pressure in a gas mixture, leaving behind the gaseous nitrogen and oxygen. In this way, CO2 can be converted from a gas (in a mixture) directly into a pure liquid. To achieve this separation, the initial gas mixture must have sufficient CO2 to begin with, such that upon compression and cooling of the mixture, the CO2 partial pressure surpasses thepressure at which the liquid form of CO2 exists. Once passed, the gaseous CO2 will condense into a liquid. Importantly, this means of separation requires substantially higher CO2 concentrations in the original gas mixture to reach the dew point of CO2 at accessible pressures and temperatures. Initial CO2 concentrations less than about 20% are relatively difficult and poor candidate gas streams for physical separation technologies; these would require chemical separation technologies. CO2 concentrations well above this level are needed for physical separation processes.

[0004] Carbon dioxide capture processes are often difficult to implement at small scales, where the rate of CO2 emission would otherwise be on the order of less than 100 tonnes per day. Such size constraints lead to prohibitive cost penalties that make CO2 capture difficult to rationalize. Examples of such small emission sources are diesel engine generators that are often made to be movable from one location to another. Such diesel engine generators may be used in the oil and gas industry, mining industry, on locomotives, or any other industry requiring small mobile electrical or mechanical power. Individually, such systems may emit from one (1) to 100 tonnes of CO2 per day which is very difficult to capture with a mobile chemical capture process, but collectively such systems comprise meaningful emissions that must be mitigated to achieve long-term CO2 emission targets. There is a need for technologies that enable CO2 capture from such small systems that is economical and does not interfere with the mobility that is required of such power generation systems.SUMMARY

[0005] Herein, in one aspect, there is provided a method of combustion comprising: supplying an oxidant-comprising gaseous material to a combustion zone; contacting the oxidant-comprising gaseous material with a fuel within the combustion zone with effect that a gaseous combustion product material is produced; and recycling a portion of gaseous post-combustion material, derived from the gaseous combustion product material, such that the supplied oxidantcomprising gaseous material includes the portion of recycled gaseous postcombustion material.

[0006] In another aspect, there is provided a method of combustion comprising: supplying an oxidant-comprising gaseous material to a combustion zone; contacting the oxidant-comprising gaseous material with a fuel within the combustion zone with effect that gaseous combustion product material, including carbon dioxide, are produced; and recycling a portion of the carbon dioxide such that the supplied oxidant-comprising gaseous material includes the recycled carbon dioxide; wherein the oxidant-comprising gaseous material is enriched in diatomic oxygen relative to atmospheric air.

[0007] In another aspect, there is provided a method of combustion comprising: supplying an oxidant-comprising gaseous material to a combustion zone; contacting the oxidant-comprising gaseous material with a fuel within the combustion zone with effect that a gaseous combustion product material is produced; fractionating a CO2-recovery ready gaseous material, derived from the gaseous combustion product material, into at least a liquid carbon dioxide-rich product and a gas stream with diatomic oxygen-comprising gaseous material; and recycling a recovered diatomic oxygen-comprising gaseous material, derived from the diatomic oxygen-comprising gaseous material, such that the supplied oxidantcomprising gaseous material includes the recovered diatomic oxygen-comprising gaseous material.BRIEF DESCRIPTION OF DRAWINGS

[0008] The preferred embodiments will now be described with the following accompanying drawings:

[0009] Figure 1 is a schematic illustration of an embodiment of a system in which is practised an embodiment of the process of the present disclosure.DETAILED DESCRIPTION

[0010] Referring to Figure 1, there is provided a method of combustion of a fuel 2 within a system 8. The system 8 includes a combustor. In some embodiments, for example, the combustor is an internal combustion engine. In some embodiments, for example, an oxidant-comprising gaseous material 4 issupplied to a combustion zone 10, of the combustor, and contacted with a fuel 2 within the combustion zone 10. In some embodiments, for example, the supplied oxidant-comprising gaseous material 4 is adscititious relative to the fuel 2.

[0011] In some embodiments, for example, the oxidant includes diatomic oxygen. Typically, the most readily available source of diatomic oxygen for a combustion process is atmospheric air. In some of these embodiments, for example, the atmospheric air has a dry gas composition including 78.08% diatomic nitrogen, 20.95% diatomic oxygen, 0.93% argon, 0.04% carbon dioxide, and trace levels of other gases such as krypton, neon, helium, methane, and hydrogen. In this respect, in some embodiments, for example, the oxidant-comprising gaseous material includes atmospheric air. In some embodiments, for example, the oxidantcomprising gaseous material 4 is enriched in diatomic oxygen relative to atmospheric air, i.e. the oxidant-comprising gaseous material 4 used in the present application comprises more diatomic oxygen than in atmospheric air. In some embodiments, for example, the oxidant-comprising gaseous material 4 comprises at least 21 volume % diatomic oxygen, based on the total volume of the oxidantcomprising gaseous material 4, such as, for example, at least 30 volume % diatomic oxygen, based on the total volume of the oxidant-comprising gaseous material, and such as, for example, up to 50 volume % diatomic oxygen, based on the total volume of the oxidant-comprising gaseous material. In some embodiments, for example, the oxidant-comprising gaseous material 4 includes less than 25 volume % diatomic nitrogen, based on the total volume of the oxidantcomprising gaseous material 4. In some embodiments, for example, the oxidantcomprising gaseous material 4 includes less than 10 volume % diatomic nitrogen, based on the total volume of oxidant-comprising gaseous material 4. In some embodiments, for example, there is an absence of diatomic nitrogen within the oxidant-comprising gaseous material 4. In some embodiments, for example, by supplying the oxidant-comprising gaseous material 4, which is enriched in diatomic oxygen relative to atmospheric air, and which, as a corollary, is depleted in diatomic nitrogen relative to atmospheric air, this results in a higher carbon dioxide concentration in gaseous combustion product material 12 (produced from the combustion zone 10, see below), and, in parallel, a lower diatomic nitrogenconcentration in the combustion products, relative to the case where the oxidantcomprising gaseous material is atmospheric air, thereby facilitating downstream physical processes for purifying carbon dioxide.

[0012] In some embodiments, for example, the fuel 2 includes hydrocarbon material, and the hydrocarbon material includes at least one hydrocarbon. Suitable sources of hydrocarbons include natural gas, propane, kerosene, diesel, petrol, charcoal, coal, wood, and any combination thereof.

[0013] The effect of contacting of the oxidant-comprising gaseous material 4 with the fuel 2 is that gaseous combustion product material 12 is produced. In some embodiments, for example, the gaseous combustion product material 12 includes carbon dioxide and water. In some embodiments, for example, the gaseous combustion product material 12 includes at least 40 volume % of carbon dioxide, based on the total volume of the gaseous combustion product material 12. In some embodiments, for example, the gaseous combustion product material 12 includes from 40 volume % of carbon dioxide, based on the total volume of the gaseous combustion product material 12, to 90 volume % of carbon dioxide, based on the total volume of the gaseous combustion product material 12.

[0014] In some embodiments, for example, a portion of a gaseous postcombustion material 14, derived from the gaseous combustion product material 12, is recycled as recycled post-combustion material 16, such that the oxidantcomprising gaseous material 4 includes the recycled gaseous post-combustion material 16. In some embodiments, for example, the gaseous post-combustion material 14 is the gaseous combustion product material 12. In some embodiments, for example, and as a necessary incident to the gaseous combustion product material 12 including at least 40 volume % carbon dioxide, based on the total volume of the gaseous combustion product material 12, the gaseous postcombustion material 14 includes at least 40 volume % carbon dioxide, based on the total volume of the gaseous post-combustion material 14. In some embodiments, for example, and as a necessary incident to the gaseous combustion product material 12 including at least 40 volume % carbon dioxide, based on the totalvolume of the gaseous combustion product material 12, and the gaseous postcombustion material 14 including at least 40 volume % carbon dioxide, based on the total volume of the gaseous post-combustion material 14, the residual gaseous post-combustion material 16 includes at least 40 volume % of carbon dioxide, based on the total volume of the recycled gaseous post-combustion material 16. In some embodiments, for example, as a necessary incident to the gaseous combustion product material 12 including from 40 volume % carbon dioxide, based on the total volume of the gaseous combustion product material 12, to 90 volume % carbon dioxide, based on the total volume of the gaseous combustion product material 12, the gaseous post-combustion material 14 includes from 40 volume % carbon dioxide, based on the total volume of the gaseous post-combustion material 14, to 90 volume % carbon dioxide, based on the total volume of the gaseous postcombustion material 14. In some embodiments, for example, as a necessary incident to the gaseous combustion product material 12 including from 40 volume % carbon dioxide, based on the total volume of the gaseous combustion product material 12, to 90 volume % carbon dioxide, based on the total volume of the gaseous combustion product material 12, and the gaseous post-combustion material 14 including from 40 volume % carbon dioxide, based on the total volume of the gaseous post-combustion material 14, to 90 volume % carbon dioxide, based on the total volume of the gaseous post-combustion material 14, the recycled gaseous post-combustion material 16 includes from 40 volume % of carbon dioxide, based on the total volume of the recycled gaseous post-combustion material 16, to 90 volume % of carbon dioxide, based on the total volume of the recycled gaseous post-combustion material 16. In some embodiments, for example, the recycling of the portion of the gaseous post-combustion material 16 is effected in accordance with a recycle ratio of at least 0.2, such as, for example, at least one (1), such as, for example, at least two (2), such as, for example, at least three (3), such as, for example, at least four (4), wherein the recycle ratio is defined as the ratio of the volumetric flowrate of the gaseous post-combustion material 16 to the volumetric flowrate of the residual gaseous post-combustion material 18. In some embodiments, for example, the recycle ratio is within a range, and the range is from 0.2 to five (5).

[0015] In some embodiments, for example, the recycled gaseous postcombustion material 16 is cooled prior to being supplied as part of the oxidantcomprising gaseous material 4 into the combustion zone 10. In some embodiments, for example, the gaseous combustion product material 12 (and, therefore, the gaseous post-combustion material 14, and the recycled gaseous post-combustion material 16) is relatively hot (in some embodiments, for example, the temperature is from 400 degrees Celsius to 1200 degrees Celsius), and must be sufficiently cooled (such as for example, to approximately 120 degrees Celsius, or below) before being supplied to the combustion zone 10 as part of the oxidant-comprising gaseous material 4. In some embodiments, for example, the cooling is sufficient such that the temperature within the combustion zone 10 is not sufficiently excessive for damaging an internal combustion engine within which the combustion zone 10 is disposed.

[0016] In some embodiments, for example, the recycling of a portion of the gaseous post-combustion material 14 is with effect that a residual gaseous postcombustion material 18 is obtained. In some embodiments, for example, and as a necessary incident to the gaseous combustion product material 12 including at least 40 volume % carbon dioxide, based on the total volume of the gaseous combustion product material 12, and the gaseous post-combustion material 14 including at least 40 volume % carbon dioxide, based on the total volume of the gaseous postcombustion material 14, the residual gaseous post-combustion material 18 includes at least 40 volume % of carbon dioxide, based on the total volume of the gaseous residual post-combustion material 18. In some embodiments, for example, as a necessary incident to the gaseous combustion product material 12 including from 40 volume % carbon dioxide, based on the total volume of the gaseous combustion product material 12, to 90 volume % carbon dioxide, based on the total volume of the gaseous combustion product material 12, and the gaseous post-combustion material 14 including from 40 volume % carbon dioxide, based on the total volume of the gaseous post-combustion material 14, to 90 volume % carbon dioxide, based on the total volume of the gaseous post-combustion material 14, the residual gaseous post-combustion material 18 includes from 40 volume % of carbon dioxide, based on the total volume of the residual gaseous post-combustion material 18, to90 volume % of carbon dioxide, based on the total volume of the residual gaseous post-combustion material 18.

[0017] In some embodiments, for example, a liquid carbon dioxide-rich product 34, enriched in carbon dioxide, is recovered from the residual gaseous post-combustion material 18. In some embodiments, for example the liquid carbon dioxide-rich product 34 is recovered from a CO2-recovery ready gaseous material 32, derived from the residual gaseous post-combustion material 18, via fractionation. In some embodiments, for example, the fractionating of the CO2- recovery ready gaseous material 32 is into at least the liquid carbon dioxide-rich product 34 and a diatomic oxygen-comprising gaseous material 36. In some of these embodiments, for example, a recovered diatomic oxygen-comprising gaseous material 38, derived from the diatomic oxygen-comprising gaseous material 36, is recycled, such that the oxidant-comprising gaseous material 4 includes the recovered diatomic oxygen-comprising gaseous material 38. In some embodiments, for example, the recovered diatomic oxygen-comprising gaseous material 38 is the diatomic oxygen-comprising gaseous material 36.

[0018] In some embodiments, for example, the fractionation includes a liquefaction within a fractionation zone 30. In this respect, in some embodiments, for example, the liquefaction is effected in response to cooling of the CO2-recovery ready gaseous material 32. In some of these embodiments, for example, for effecting the liquefaction, the CO2-recovery ready gaseous material 32 is cooled to a cooler temperature, wherein the cooler temperature is from zero (0) degrees Celsius to minus 80 degrees Celsius. In this respect, in some embodiments, for example, the liquefying zone 30 is disposed at liquefying zone temperature, and the liquefying zone temperature is from zero (0) degrees Celsius to minus 80 degrees Celsius. In some embodiments, for example, the liquefying is effected in response to compression of the CO2-recovery ready gaseous material 32.

[0019] In some embodiments, for example, the fractionation includes a compression within the fractionation zone 30. In this respect, in some embodiments, for example, to effect the fractionation, the CO2-recovery readygaseous material 32 is compressed with effect that the CO2-recovery ready gaseous material 32 becomes disposed at a higher pressure, and the higher pressure is from 100 pounds per square inch to 2000 pounds per square inch. In this respect, in some embodiments, for example, the fractionation zone 30 is disposed at a fractionation zone pressure, and the fractionation zone pressure is from 100 pounds per square inch to 2000 pounds per square inch. In some embodiments, for example, the liquid carbon dioxide-rich product 34 and the diatomic oxygencomprising gaseous material 36 are recovered from the fractionation zone 30 via gravity separation. In some embodiments, for example, the liquid carbon dioxiderich product 34 includes at least 80 volume % CO2, based on the total volume of the liquid carbon dioxide-rich product 34, such as, for example, at least 90 volume % CO2, based on the total volume of the liquid carbon dioxide-rich product 34, such as, for example, at least 95 volume % CO2, based on the total volume of the liquid carbon dioxide-rich product 34 based on the total weight of the liquid carbon dioxide-rich product 34, and the diatomic oxygen-comprising gaseous material 36 includes at least 30 volume % diatomic oxygen, based on the total volume of the diatomic oxygen-comprising gaseous material 36, such as, for example, at least 40 volume % diatomic oxygen, based on the total volume of the diatomic oxygencomprising gaseous material 36, such as, for example, at least 50 volume % diatomic oxygen, based on the total volume of the diatomic oxygen- comprising gaseous material 36.

[0020] In some embodiments, for example, prior to the fractionation, water is condensed, within a condensation zone 20, from a condensation-ready gaseous post combustion material 22, derived from the residual gaseous post-combustion material 18 (in some embodiments, for example, the condensation-ready gaseous post combustion material 22 is the residual gaseous post-combustion material 18), with effect that water 24 and a water-depleted post-combustion gaseous material 26 are obtained. The CO2-recovery ready gaseous material 32 is derived from the water-depleted post-combustion gaseous material 26, and, in some embodiments, for example, the CO2-recovery ready gaseous material 32 is the water-depleted post-combustion gaseous material 26. In some embodiments, for example, the condensing of the water is effected in response to cooling of the condensation-ready post combustion material 22 within the condensation zone 20. In this respect, in some of these embodiments, for example, for effecting the condensation, the condensation zone 20 is disposed at a temperature of less than 100 degrees Celsius, such as, for example, less than 25 degrees Celsius. In some of these embodiments, for example, the temperature of the condensation zone is greater than zero (0) degrees Celsius for effecting the condensation. In some embodiments, for example, the water condensation is effected in response to compression of the condensation-ready post combustion material 22. In this respect, in some of these embodiments, for example, the condensation zone 20 is disposed at a pressure of greater than one (1) atmosphere for effecting the condensation. In some embodiments, molecular sieve dehydration systems may be used to separate the water from stream 22.

[0021] In some embodiments, for example, the oxidant-comprising gaseous material 4 is an admixture including the recycled post-combustion material 16, the recovered diatomic oxygen-comprising gaseous material 38, and a diatomic oxygen-rich gaseous material 48 that is derived from (and, in some embodiments, for example, is) a diatomic oxygen-rich gaseous fractionation product 44.

[0022] In some embodiments, for example, the diatomic oxygen-rich gaseous fractionation product 44 is derived from atmospheric air 42 that is fractionated, within a fractionation zone 40, into at least the diatomic oxygen-rich gaseous fractionation product 44 and a diatomic nitrogen-rich gaseous fractionation product 46. In some embodiments, for example, the fractionation is effected via pressure swing adsorption, vacuum pressure swing adsorption, cryogenic air separation, a membrane separation process, or any combination thereof, or alternative technology that separates the atmospheric air 42 into at least the diatomic oxygenrich gaseous fractionation product 44 and the diatomic nitrogen-rich gaseous fractionation product 46. In some embodiments, for example, the diatomic oxygenrich gaseous material 48 comprises at least 50 volume % diatomic oxygen, based on the total volume of the diatomic oxygen-rich gaseous material 48, such as, for example at least 80 volume % diatomic oxygen, based on the total volume of the diatomic oxygen-rich gaseous material 48, or it may be for example as high as 99volume % diatomic oxygen based on the total volume of the diatomic oxygen-rich gaseous material 48. In most embodiments the volumetric diatomic oxygen concentration will be greater than 95 volume %.

[0023] In some embodiments, for example, the recycling of the portion of the gaseous post-combustion material 16, and admixing with gaseous material which is enriched in diatomic oxygen, relative to air (such as, for example, the diatomic oxygen-rich gaseous material 48 and the recovered diatomic oxygen-comprising gaseous material 38), is with effect that the oxidant-comprising gaseous material 4 becomes sufficiently enriched in carbon dioxide such that production of the gaseous combustion product material 14, that is enriched in carbon dioxide, is effected, thereby facilitating downstream physical processes (such as compression and / or liquefaction) for purifying carbon dioxide, as discussed above. Also, in some embodiments, for example, the recycling of the portion 16 of the gaseous postcombustion material, and admixing with gaseous material which is enriched in diatomic oxygen, relative to air, is with additional effect that undesirably high temperatures within the combustion zone 10 is avoided such that undesirable damage to an engine, embodying the combustion zone 10, is avoided.

[0024] In the above description, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the present disclosure. However, it will be apparent to one skilled in the art that these specific details are not required in order to practice the present disclosure. Although certain dimensions and materials are described for implementing the disclosed example embodiments, other suitable dimensions and / or materials may be used within the scope of this disclosure. All such modifications and variations, including all suitable current and future changes in technology, are believed to be within the sphere and scope of the present disclosure. All references mentioned are hereby incorporated by reference in their entirety.

Claims

CLAIMS1. A method of combustion comprising: supplying an oxidant-comprising gaseous material to a combustion zone; contacting the oxidant-comprising gaseous material with a fuel within the combustion zone with effect that gaseous combustion product material is produced; and recycling a portion of gaseous post-combustion material, derived from the gaseous combustion product material, such that the supplied oxidant-comprising gaseous material includes the recycled gaseous post-combustion material; wherein the oxidant-comprising gaseous material is enriched in diatomic oxygen relative to atmospheric air.

2. The method of claim 1, wherein the oxidant-comprising gaseous material comprises at least 21 volume % diatomic oxygen, based on the total volume of the oxidant-comprising gaseous material.

3. The method of claim 2, further comprising fractionating ambient air into at least a diatomic oxygen-rich gaseous fractionation product and a nitrogenrich gaseous fractionation product, wherein the oxidant-comprising gaseous material includes a diatomic oxygen-rich gaseous material that is derived from the diatomic oxygen-rich gaseous fractionation product.

4. The method of any one of claims 1 to 3, wherein the recycled gaseous postcombustion material includes at least 40 volume % carbon dioxide, based on the total volume of the recycled gaseous post-combustion material.

5. The method of any one of claims 1 to 4, wherein the recycled gaseous postcombustion material includes from 40 volume % carbon dioxide, based on the total volume of the recycled gaseous post-combustion material, to 90 volume % carbon dioxide, based on the total volume of the recycled gaseous post-combustion material.

6. The method of any one of claims 1 to 5, wherein the oxidant-comprising gaseous material includes less than 25% diatomic nitrogen based on the total volume of the oxidant-comprising gaseous material.

7. The method as claimed in any one of claims 1 to 6, wherein the recycling of the recycled gaseous post-combustion material is effected in accordance with a recycle ratio of at least 0.2.

8. The method of any one of claims 1 to 7, further comprising cooling the portion of the gaseous post-combustion material, being recycled, to 120 degrees Celsius or below.

9. The method of any one of claims 1 to 8, wherein the recycling is with effect that a residual gaseous post-combustion material is obtained, and further comprising fractionating a condensation-ready gaseous post-combustion material, derived from the residual gaseous post-combustion material, into at least liquid water and water-depleted post-combustion gaseous material.

10. The method of claim 9, wherein the fractionating of the condensation-ready gaseous post-combustion material includes condensing water of the condensation-ready gaseous post-combustion material, such that a water- depleted post-combustion gaseous material is produced.

11. The method of claim 9 or 10, further comprising fractionating a CO2 recovery- ready gaseous material, derived from the water-depleted postcombustion gaseous material, into at least a liquid carbon dioxide-rich product and a residual diatomic oxygen-comprising gaseous material.

12. The method of claim 11, wherein the fractionating of the CO2 recovery- ready gaseous material includes liquefaction of the CO2 from the CO2 recoveryready gaseous material, such that a diatomic oxygen-comprising gaseous material is produced.

13. The method of claim 11 or 12, further comprising recycling a recovered diatomic oxygen-comprising gaseous material, derived from the diatomic oxygen-comprising gaseous material, such that the supplied oxidantcomprising gaseous material includes the recycled recovered diatomic oxygen-comprising gaseous material.

14. The method as claimed in any one of claims 1 to 13, wherein the supplied oxidant-comprising gaseous material is adscititious relative to the fuel.

15. A method of combustion comprising: supplying an oxidant-comprising gaseous material to a combustion zone; contacting the oxidant-comprising gaseous material with a fuel within the combustion zone with effect that gaseous combustion product material, including carbon dioxide, are produced; and recycling a portion of the carbon dioxide such that the supplied oxidantcomprising gaseous material includes the recycled carbon dioxide; wherein the oxidant-comprising gaseous material is enriched in diatomic oxygen relative to atmospheric air.

16. The method of claim 15, wherein the gaseous combustion product material includes from 40 volume % carbon dioxide, based on the total volume of the gaseous combustion production material, to 90 volume % carbon dioxide, based on the total volume of the gaseous combustion product material.

17. The method of claim 15 or 16, wherein the oxidant-comprising gaseous material includes less than 25% diatomic nitrogen, based on the total volume of the oxidant-comprising gaseous material.

18. The method of any one of claims 15 to 17, wherein the oxidant-comprising gaseous material includes from 21 volume % diatomic oxygen, based on the total volume of the oxidant-comprising gaseous material, to 50 volume %diatomic oxygen, based on the total volume of the oxidant-comprising gaseous material.

19. The method of any one of claims 15 to 18, further comprising cooling the recycled carbon dioxide.

20. The method of any one of claims 15 to 19, wherein the recycling is with effect that a residual gaseous post-combustion material is obtained, and further comprising fractionating a condensation-ready gaseous postcombustion material, derived from the residual gaseous post-combustion material into at least liquid water and water-depleted post-combustion gaseous material.

21. The method of claim 20, further comprising fractionating a CO2 recoveryready gaseous material, derived from the water-depleted post-combustion gaseous material, into at least a liquid carbon dioxide-rich product and a diatomic oxygen-comprising gaseous material.

22. The method of claim 21, further comprising recycling a recovered diatomic oxygen-comprising gaseous material, derived from the diatomic oxygencomprising gaseous material, such that the supplied oxidant-comprising gaseous material includes the recycled recovered diatomic oxygencomprising gaseous material.

23. A method of combustion comprising: supplying an oxidant-comprising gaseous material to a combustion zone; contacting the oxidant-comprising gaseous material with a fuel within the combustion zone with effect that a gaseous combustion product material is produced;fractionating a CO2-recovery ready gaseous material, derived from the gaseous combustion product material, into at least a liquid carbon dioxiderich product and a diatomic oxygen-comprising gaseous material; and recycling a recovered diatomic oxygen-comprising gaseous material, derived from the diatomic oxygen-comprising gaseous material, such that the supplied oxidant-comprising gaseous material includes the recycled recovered diatomic oxygen-comprising gaseous material.

24. The method of claim 23, wherein the oxidant-comprising gaseous material includes from 21 volume % diatomic oxygen, based on the total volume of the oxidant-comprising gaseous material, to 50 volume % diatomic oxygen, based on the total volume of the oxidant-comprising gaseous material.

25. The method of claim 24, further comprising fractionating ambient air into at least a diatomic oxygen-rich gaseous fractionation product and a nitrogenrich gaseous fractionation product, wherein the oxidant-comprising gaseous material includes a diatomic oxygen-rich gaseous material that is derived from the diatomic oxygen-rich gaseous fractionation product.

26. The method of any one of claims 23 to 25, wherein the gaseous combustion product material includes from 40 volume % carbon dioxide, based on the total volume of the gaseous combustion product material, to 90 volume % carbon dioxide, based on the total volume of the gaseous combustion product material.

27. The method of claim 26, wherein the oxidant-comprising gaseous material includes less than 25 volume % diatomic nitrogen, based on the total volume of the oxidant-comprising gaseous material.

28. The method of claim 26 or 27, wherein the fractionating of the CO2 recoveryready gaseous material includes liquefaction of the CO2 recovery- ready gaseous material, such that at least the diatomic oxygen-comprising gaseous material and liquid CO2 is produced.

29. The method of claim 28, wherein the liquefaction of the CO2 recovery- ready gaseous material includes cooling the CO2 recovery- ready gaseous material.

30. The method of claim 29, wherein: the cooling of the CO2 recovery- ready gaseous material comprises is with effect that the CO2 recovery- ready gaseous material becomes disposed at a cooler temperature, wherein the cooler temperature is from 0 degrees Celsius to minus 80 degrees Celsius.

31. The method of claim 26 or 27, wherein the fractionation of the CO2 recoveryready gaseous material includes compressing the CO2 recovery- ready gaseous material.

32. The method as claimed in claim 31, wherein the compressing is with effect that the CO2 recovery- ready gaseous material becomes disposed at a higher pressure, and the higher pressure is from 100 pounds per square inch to 2000 pounds per square inch.

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