CHEMICAL LOOPING COMBUSTION AND CARBON DIOXIDE DIRECT REDUCTION (CLC-CDR) INTEGRATION SYSTEM AND OPERATION METHOD THEREOF

Abstract

The present invention relates to a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system and an operation method thereof, particularly to a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system including: an air reactor, wherein an oxygen carrier particle is oxidized by reacting with injected air and air from which oxygen was partially removed is discharged; a fuel reactor, wherein the oxidized oxygen carrier particle is supplied, a supplied fuel is reacted to reduce the oxidized oxygen carrier particle, and carbon dioxide including H.sub.2O is discharged; and a carbon dioxide reduction reactor, wherein the reduced oxygen carrier particle is supplied, supplied carbon dioxide is reacted to discharge carbon monoxide, and the reduced oxygen carrier particle is partially oxidized and supplied to the air reactor.

Claims

1. A chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system comprising: an air reactor, wherein an oxygen carrier particle is oxidized by reacting with injected air and air from which oxygen was partially removed is discharged; a fuel reactor, wherein the oxidized oxygen carrier particle is supplied, a supplied fuel is reacted to reduce the oxidized oxygen carrier particle, and carbon dioxide including H.sub.2O is discharged; and a carbon dioxide reduction reactor, wherein the reduced oxygen carrier particle is supplied, supplied carbon dioxide is reacted to discharge carbon monoxide, and the reduced oxygen carrier particle is partially oxidized and supplied to the air reactor.

2. The chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system of claim 1, comprising a carbon dioxide supply line that connects an outlet portion of the fuel reactor and the carbon dioxide reduction reactor, wherein carbon dioxide supplied to the carbon dioxide reduction reactor is one in which H.sub.2O was removed from a gas discharged from the fuel reactor.

3. The chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system of claim 2, wherein the air reactor is of an exothermic reaction (oxidizer), the fuel reactor is of an endothermic reaction (reducer), the carbon dioxide reduction reactor is of an endothermic reaction and the whole system is of an exothermic reaction, and steam or electricity is generated by a heat discharged from the air reactor.

4. The chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system of claim 2, comprising a first bypass line that is connected in-between one side of the carbon dioxide supply line and a discharge portion of the carbon dioxide reduction reactor, wherein a ratio of carbon monoxide and carbon dioxide required for a downstream process is controlled by mixing a part of carbon dioxide discharged from the fuel reactor with a gas discharged from the carbon dioxide reduction reactor.

5. The chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system of claim 4, further comprising a heat exchanger that heats the carbon dioxide reduction reactor by using a heat of a gas discharged from the air reactor as a heat source.

6. The chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system of claim 5, comprising a second bypass line that connects between a rear end of the heat exchanger and an air injection portion of the air reactor, wherein a gas discharged from the air reactor is supplied to the air injection portion of the air reactor.

7. The chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system of claim 6, wherein a mixing ratio of air and a gas discharged from the air reactor is adjusted to control an oxidation-reduction state of the oxygen carrier particle.

8. An operation method of a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system comprising steps of: reacting air injected into an air reactor and an oxygen carrier particle to oxidize the oxygen carrier particle, and discharging air from which oxygen was partially removed; supplying the oxidized oxygen carrier particle to a fuel reactor, reacting a supplied fuel to reduce the oxidized oxygen carrier particle, and discharging carbon dioxide including H.sub.2O; and supplying the reduced oxygen carrier particle to a carbon dioxide-reactor, supplying carbon dioxide in which H.sub.2O was removed from a gas discharged from the fuel reactor to discharge carbon monoxide, and partially oxidizing the reduced oxygen carrier particle to be supplied to the air reactor.

9. The operation method of a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system of claim 8, further comprising a step of: generating steam or electricity by a heat discharged from the air reactor.

10. The operation method of a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system of claim 8, further comprising a step of: mixing a part of carbon dioxide that is discharged from the fuel reactor through a first bypass line connected in-between one side of a carbon dioxide supply line and a discharge portion of a carbon dioxide reduction reactor, with a gas discharged from the carbon dioxide reduction reactor, to control a ratio of carbon monoxide and carbon dioxide required for a downstream process.

11. The operation method of a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system of claim 10, further comprising a step of: supplying a gas discharged from the air reactor to a heat exchanger fitted to the carbon dioxide reduction reactor to heat the carbon dioxide reduction reactor.

12. The operation method of a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system of claim 11, further comprising a step of: supplying a gas discharged from the air reactor to an air injection portion of the air reactor through a second bypass line that connects between a rear end of the heat exchanger and the air injection portion of the air reactor.

13. The operation method of a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system of claim 12, wherein a mixing ratio of air and a gas discharged from the air reactor is adjusted to control an oxidation-reduction state of the oxygen carrier particle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0064] The accompanying drawings of this specification exemplify a preferred embodiment of the present disclosure, the spirit of the present disclosure will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, and thus it will be understood that the present disclosure is not limited to only contents illustrated in the accompanying drawings.

[0065] FIG. 1 is a conceptual diagram of a chemical looping combustion system.

[0066] FIG. 2 is a conceptual diagram of chemical looping reverse water gas shift (RWGS-CL) technology.

[0067] FIG. 3 is a conceptual diagram of a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system according to an embodiment of the present disclosure.

[0068] FIG. 4 is a flowchart of an operation method of a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system according to an embodiment of the present disclosure.

[0069] FIG. 5 is a conceptual diagram of a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system showing control functions according to an embodiment of the present disclosure.

DETAILED DESCRIPTION

[0070] Hereinafter, the aforementioned aims, other aims, features and advantageous effects of the present disclosure will be understood easily referring to preferable embodiments related to the accompanying drawings. However, the present disclosure is not limited to embodiments described in this specification, and may be embodied into other forms. Preferably, the embodiments in this specification are provided in order to allow disclosed contents to be exhaustive and to communicate the concept of the present disclosure to those skilled in the art. In this specification, when a certain element is placed on another element, this means that it may be formed directly thereon or that the third element may be interposed between them. Further, in the drawings, the thickness of an element may be overstated in order to explain the technical content thereof efficiently.

[0071] The embodiments described in this specification will explained with reference to a cross-sectional view and/or a plane view. In the drawings, the thickness of a film and a region may be overstated in order to explain the technical content thereof efficiently. Accordingly, the form of exemplary drawings for a fabrication method and/or an allowable error et cetera may be modified. Thus, the embodiments according to the present disclosure are not limited to specific forms illustrated herein, but may include variations in the form resulting from the fabrication method. For example, the region illustrated with perpendicular lines may have a form to be rounded or with a predetermined curvature. Thus, regions exemplified in the drawings have attributes, and shapes thereof exemplify specific forms rather than limiting the scope of the present disclosure. In the various embodiments of this specification, terms such as ‘first’ and ‘second’ et cetera are used to describe various elements, but these elements should not be limited to such terms. These terms are merely used to distinguish one element from others. The embodiments explained and exemplified herein may include complementary embodiments thereto.

[0072] The terms used in this specification is to explain the embodiments rather than limiting the present disclosure. In this specification, the singular expression includes the plural expression unless specifically stated otherwise. The terms, such as ‘comprise” and/or “comprising” do not preclude the potential existences of one or more elements.

[0073] When describing the following specific embodiments, various kinds of specific contents are made up to explain the present disclosure in detail and to help understanding thereof. However, it will be apparent for those who have knowledge to the extent of understanding the present disclosure that the present disclosure can be used without any of these specific contents. In a certain case when describing the present disclosure, the content that is commonly known to the public but is largely irrelevant to the present disclosure is not described in order to avoid confusion.

[0074] Hereinafter, configurations and functions of a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) system and an operation method thereof will be described.

[0075] FIG. 3 is a conceptual diagram of a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system according to an embodiment of the present disclosure. FIG. 4 is a flowchart of an operation method of a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system according to an embodiment of the present disclosure.

[0076] FIG. 3 shows a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system according to an embodiment of the present disclosure, which is characterized in that chemical looping combustion combined with the aforementioned, chemical looping combustion technology as shown in FIG. 1 and RWGS-CL technology as shown in FIG. 2 is closely combined with CO.sub.2 direct reduction (CLC-CDR, Chemical Looping Combustion) technology.

[0077] FIG. 3 is of a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system according to an embodiment of the present disclosure, and it is seen that the system is, in general, configured to include an air reactor, a fuel reactor and a carbon dioxide reduction reactor.

[0078] An air reactor 10 includes an air injection portion 11 for injecting air, a gas discharge portion 12 for discharging a discharge gas, an oxygen carrier particle supply portion 13 for supplying an oxygen carrier particle, and an oxygen carrier particle outlet portion 14 for discharging an oxidized oxygen carrier particle. Herein, the oxygen carrier particle is oxidized by reacting with injected air, and air in which oxygen was partially removed is discharged (S1).

[0079] As taking an example allowing for using a Ni based particle as an oxygen carrier particle and methane (CH.sub.4) as a fuel in order to take account of a reaction heat in the whole reaction, in the air reactor 10, as seen in following Formula (13), oxygen in air and a metal (Ni) are reacted to generate a metal oxide (NiO) and a heat is released during this process.

[0080] Air Reactor: Exothermic Reaction

3Ni+1.5O.sub.2.fwdarw.3NiO ΔH.sup.0.sub.298=−719.1 kJ  (13)

[0081] In addition, a fuel reactor 20 is configured to include a fuel supply portion 21 for supplying a fuel, an oxygen carrier particle inlet portion 22 for inletting an oxygen carrier particle, an outlet portion for discharging a discharge gas and an oxygen carrier particle discharge portion 24. In the fuel reactor, an oxidized oxygen carrier particle is supplied and reacted with a supplied fuel to reduce the oxidized oxygen carrier particle and carbon dioxide including H.sub.2O is discharged (S2).

[0082] That is, the oxygen carrier particle oxidized by air is moved to the fuel reactor 20 and reacted with methane (CH.sub.4) as seen in following Formula (14) to generate CO.sub.2 and H.sub.2O. Generated steam is condensed into a liquid form and removed to obtain a high concentration of CO.sub.2. The reduction reaction of the oxygen carrier particle by CH.sub.4 is an endothermic reaction, wherein a heat may be supplied by a high temperature of oxygen carrier particle that is inlet from the air reactor, thus involving no additional energy supply.

[0083] Fuel Reactor: Endothermic Reaction

4NiO+CH.sub.4.fwdarw.4Ni+CO.sub.2+2H.sub.2O ΔH.sup.0.sub.298=156.2 kJ  (14)

[0084] A carbon dioxide reduction reactor 30 may be configured to include an oxygen carrier particle supply portion 31, a carbon dioxide inlet portion 32, a carbon monoxide discharge portion 33 and an oxygen carrier particle discharge portion 34. The reduced oxygen carrier particle is supplied to the carbon dioxide reduction reactor 30 and reacted with supplied carbon dioxide to discharge carbon monoxide, and the reduced oxygen carrier particle is partially oxidized and supplied to the air reactor.

[0085] Further, the system may further include a carbon dioxide supply line 40 that connects the outlet portion 23 of the fuel reactor and the carbon dioxide inlet portion 32 of the carbon dioxide reduction reactor 30. Accordingly, carbon dioxide supplied to the carbon dioxide reduction reactor 30 is one in which H.sub.2O was removed from a gas discharged from the fuel reactor with a condenser 41.

[0086] That is, in the fuel reactor 20, NiO is reacted with CH.sub.4 to be reduced into Ni, and reduced Ni is moved to the carbon dioxide reduction reactor 30. In the carbon dioxide reduction reactor 30, as seen in following Formula (15), Ni reduced in the fuel reactor 20 is reacted with CO.sub.2 to generate CO and Ni is partially oxidized into NiO.

[0087] CO.sub.2 Reduction Reactor: Endothermic Reaction

Ni+CO.sub.2.fwdarw.NiO+CO ΔH.sup.0.sub.298=43.3 kJ  (15)

[0088] The whole reaction equation of CLC-CDR technology is as following Formula (16) and becomes equal to a partial oxidation of CH.sub.4. Further, the reaction of Formula (16) is an exothermic reaction, allowing a spontaneous reaction. That is, as adding the oxidation reaction of the oxygen carrier particle that is an exothermic reaction as Formula (13) to the RWGS reaction that is an endothermic reaction as Formula (6), the whole reaction equation is converted into an exothermic reaction by partial oxidation as following Formula (16), allowing generating CO without any supplies of energy and hydrogen from the outside and generating steam and electricity by using a high temperature of gas discharged from the air reactor 10.

[0089] Whole Reaction Equation: Exothermic Reaction

CH.sub.4+1.5O.sub.2.fwdarw.CO+2H.sub.2O ΔH.sup.0.sub.298=−519.6 kJ  (16)

[0090] As mentioned above, as applying CLC-CDR technology according to the present disclosure, on the contrary to chemical looping combustion that discharges CO.sub.2 and thus requires additional CO.sub.2 storing or converting technology, it is allowable to obtain a useful material, CO, while generating steam and electricity.

[0091] In addition, as compared to RWGS and RWGS-CL, it is allowable to use CH.sub.4 as a reducing agent instead of high priced hydrogen, being economical.

[0092] Further, air in which oxygen was consumed is discharged from the air reactor 10, a high concentration of CO.sub.2 is inherently separated in the fuel reactor 20, and unreacted CO.sub.2 and a reaction product, CO are discharged from the carbon dioxide reduction reactor 30. Thus, it is allowable to separate a resulting product at low cost as compared to the RWGS reaction.

[0093] Further, the whole reaction equation is an exothermic reaction as formula (16) and thus there is an advantageous effect allowing generating CO from a discharged gas while generating steam and electricity by using a high temperature of gas discharged from the air reactor 10.

[0094] FIG. 5 a conceptual diagram of a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system showing control functions according to an embodiment of the present disclosure.

[0095] As shown in FIG. 5, it is seen that the system may include a first bypass line 42 that is connected in-between one side of a carbon dioxide supply line 40 and the discharge portion 33 of the carbon dioxide reduction reactor. Thus, a part of carbon dioxide discharged from the fuel reactor 20 through the first bypass line 42 is mixed with a gas discharged from the carbon dioxide reduction reactor 30, allowing controlling a ratio of carbon monoxide and carbon dioxide required for a downstream process. That is, as shown in FIG. 5, it is allowable to control a ratio of carbon monoxide and carbon dioxide required for the downstream process in a manner of mixing a part of carbon dioxide discharged from the fuel reactor 20 with a gas discharged from the carbon dioxide reduction reactor 30 (Flow A).

[0096] Further, in an embodiment of the present disclosure, the system may be configured to include a heat exchanger 50 that heats the carbon dioxide reduction reactor 30 by using a heat of a gas discharged from the air reactor 10 as a heat source. Thus, a high temperature of gas discharged from the air reactor 10 is supplied to the heat exchanger 50 fitted to the carbon dioxide reduction reactor 30, allowing supplying a heat required in the carbon dioxide reduction reactor 30. That is, as shown in FIG. 5, the carbon dioxide reduction reactor is of an endothermic reaction. Accordingly, it is allowable to supply energy required in the carbon dioxide reduction reactor 30 by using, as a heat exchange fluid, a high temperature of gas discharged from the air reactor 10 that is of an exothermic reaction (Flow B), thus involving no additional discharging of CO.sub.2 during the energy supply to the CO.sub.2 reduction reactor 30.

[0097] In addition, in an embodiment of the present disclosure, the system includes a second bypass line 51 that connects between a rear end of the heat exchanger 50 and the air injection portion 11 of the air reactor, allowing supplying a gas discharged from the air reactor 10 to the air injection portion 11 of the air reactor.

[0098] That is, in order to increase a reduction state of an oxygen carrier particle that is inlet to the carbon dioxide reduction reactor 30, it is allowable to use a gas discharged from the air reactor 10 (air in which a part of oxygen was consumed, showing a low oxygen concentration as compared to the air), instead of injecting air into the air reactor 10. As shown in FIG. 5, an oxidation-reduction state of an oxygen carrier particle may be controlled by recycling a gas discharged from the air reactor 10 (Flow C) and using the recycled gas instead pure air, or mixing it with pure air and using a mixture thereof. Further, when recycling the gas discharged from the air reactor 10 as the above to the air reactor 10, the temperature thereof is higher than that of air in the atmosphere, allowing enhancing thermal efficiency of the air reactor 10.

[0099] Further, the configuration and method of the embodiments as described above are not restrictively applied to the aforementioned apparatus and method. The whole or part of the respective embodiments may be selectively combined so as to make various modifications of the embodiments.

FIGURE REFERENCE NUMBERS

[0100] 10: an air reactor [0101] 11: an air injection portion [0102] 12: a gas discharge portion [0103] 13: an oxygen carrier particle supply portion [0104] 14: an oxygen carrier particle outlet portion [0105] 20: a fuel reactor [0106] 21: a fuel supply portion [0107] 22: an oxygen carrier particle inlet portion [0108] 23: an outlet portion [0109] 24: an oxygen carrier particle discharge portion [0110] 30: a carbon dioxide reduction reactor [0111] 31: an oxygen carrier particle supply portion [0112] 32: a carbon dioxide inlet portion [0113] 33: a carbon monoxide discharge portion [0114] 34: an oxygen carrier particle discharge portion [0115] 40: a carbon dioxide supply line [0116] 41: a condenser [0117] 42: a first bypass line [0118] 50: a heat exchanger [0119] 51: a second bypass line [0120] 100: a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system