Carbon dioxide enrichment device under pure oxygen combustion

Abstract

The invention relates to the technical field of carbon dioxide capture, in particular to a carbon dioxide enrichment device under pure oxygen combustion. The device comprises a decomposing furnace and an air combustion mechanism, a gas injection port is formed in the bottom of the decomposing furnace; the air-fuel mechanism comprises an air-fuel shell and a pure oxygen air distributor, an air-fuel chamber is arranged in the air-fuel shell, and an outlet of the air-fuel chamber is communicated with the fuel gas injection port; the pure oxygen air distributor is arranged at the bottom of the air combustion chamber, an inlet of the pure oxygen air distributor is used for inputting oxygen, and the pure oxygen air distributor is provided with a plurality of outlets which are distributed at intervals in the circumferential direction and communicate with the air combustion chamber. The arrangement of the pure oxygen air distributor enables oxygen to enter the decomposing furnace in a dispersed mode, so that the oxygen can make full contact with pulverized coal and raw materials, and the combustion efficiency and the decomposing effect of the raw materials are improved. Oxygen sprayed out of the pure oxygen air distributor forms a spouting air cushion layer at the bottom of the air combustion chamber, high-temperature powder can be prevented from being deposited at the bottom of the air combustion chamber, meanwhile, airflow can penetrate through sintered particles, and it is guaranteed that the production process can be stably carried out.

Description

Technical Field

[0001] The invention relates to the technical field of carbon dioxide capture, and in particular to a carbon dioxide enrichment device under pure oxygen combustion. Background Art

[0002] The cement industry is one of the main industries for CO2 emission in my country, and the CO2 generated by cement production accounts for 7% of the total global CO2 emission. The traditional cement industry carbon capture mainly adopts chemical absorption process and external combustion high temperature calcination rotary kiln decarbonization process, among which: the chemical absorption process uses amine solution to absorb and desorb to obtain high concentration of carbon dioxide. The advantage of this process is that the equipment has been maturely applied in the chemical industry, and the disadvantage is that the power consumption is large and the system consumption is high; the principle of the external combustion high temperature calcination rotary kiln carbon capture process is to separate a certain amount of raw materials originally sent to the preheater discharge pipe according to the requirements of the amount of CO2 captured and send it to the external combustion high temperature calcination rotary kiln for decomposition. The advantage of this process is that the principle is simple, and the investment cost and operation cost are relatively low. Its disadvantage is that it has very high requirements for the high temperature resistance of the kiln shell material.

[0003] In view of the defects of traditional carbon capture technology, the field has begun to use pure oxygen combustion technology to capture cement carbon. The principle of pure oxygen combustion technology is to use high-purity oxygen as fuel to replace traditional air. This process can directly obtain original cement kiln flue gas with a high concentration of CO2 of more than 70%.

[0004] The existing carbon capture device using pure oxygen combustion process only has one oxygen inlet at the bottom of the decomposition furnace. Under this structure, the oxygen entering the decomposition furnace is difficult to fully diffuse, resulting in the oxygen being unable to fully contact with the coal powder and raw meal, thereby affecting the decomposition effect of the raw meal. Summary of the invention

[0005] The purpose of the present invention is to provide a carbon dioxide enrichment device under pure oxygen combustion to solve the technical problem in the prior art that the oxygen entering the decomposition furnace is difficult to fully diffuse, resulting in the inability of oxygen to fully contact with the raw materials in the furnace, thereby affecting the decomposition effect of the raw materials.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A carbon dioxide enrichment device under pure oxygen combustion, comprising:

[0008] A decomposition furnace having a gas injection port at the bottom;

[0009] The air-fuel mechanism comprises an air-fuel shell and a pure oxygen air distributor, wherein: an air-fuel chamber is arranged inside the air-fuel shell, and the outlet of the air-fuel chamber is connected to the fuel gas injection port; the pure oxygen air distributor is arranged at the bottom of the air-fuel chamber, and the inlet of the pure oxygen air distributor is used to input oxygen, and the pure oxygen air distributor has a plurality of outlets which are distributed at intervals along the circumference and connected to the air-fuel chamber.

[0010] Furthermore, it also includes a dust removal and cooling mechanism, the inlet of the dust removal and cooling mechanism is connected with the outlet at the top of the decomposition furnace through a pipeline;

[0011] The air-combustion chamber is provided with a pure oxygen inlet and a circulating gas inlet. The pure oxygen inlet is communicated with the outlet of the pure oxygen air distributor, and the circulating gas inlet is communicated with the outlet of the dust removal and cooling mechanism through a pipeline.

[0012] Furthermore, the air-fuel mechanism further includes a first burner and a circulating air blower, wherein:

[0013] The first burner is arranged on the end surface where the circulating gas inlet is located, and the outlet end of the first burner extends into the air combustion chamber;

[0014] The circulating air blower is mounted on the first burner, and the inlet of the circulating air blower is connected to the outlet of the dust removal and cooling mechanism through a pipeline. The circulating air blower is provided with a plurality of outlets distributed at intervals along the circumferential direction. The number of the circulating air inlets is multiple and corresponds one-to-one with the outlets of the circulating air blower.

[0015] Furthermore, the first burner includes a fuel spray gun, a first coal powder channel, a first oxygen channel and a circulating gas channel which are sequentially mounted from the inside to the outside, and the inlet of the circulating gas channel is connected to the outlet of the dust removal and cooling mechanism through a pipeline.

[0016] Furthermore, the air-fuel casing is a volute structure, comprising a main pipe extending in a spiral shape and an air intake end plate arranged at the end of the main pipe, the bottom of the main pipe is provided with the pure oxygen inlet, and the air intake end plate is provided with the circulating gas inlet.

[0017] Furthermore, it also includes one or more annular oxygenators, which are mounted on the decomposition furnace, the inlet of the annular oxygenator is used to input oxygen, and the annular oxygenator is provided with a plurality of outlets distributed at intervals along the circumference and connected to the decomposition furnace.

[0018] Furthermore, a second nozzle is provided at each outlet of the annular oxygenator, and a plurality of the second nozzles are arranged in a cutting rotary cutting manner;

[0019] The arrangement rotation direction of the plurality of second nozzles is the same as the rotation direction of the air-fuel casing.

[0020] Furthermore, the air-fuel mechanism further includes a slag discharge channel, which is located at the bottom of the air-fuel chamber and communicates with the air-fuel chamber;

[0021] The pure oxygen air distributor is sleeved on the slag discharge channel.

[0022] Furthermore, it also includes a plurality of second burners, which are installed on the side wall of the decomposition furnace and the outlet ends of the second burners extend into the decomposition furnace;

[0023] The second burner includes a second pulverized coal channel and a second oxygen channel.

[0024] Furthermore, a plurality of raw material feed boxes are provided on the side wall of the decomposition furnace, wherein one or more of the raw material feed boxes are provided with the second burner;

[0025] And / or, a hollow scattering sheet is laid at the outlet of the second coal powder channel.

[0026] Furthermore, the decomposition furnace is provided with a pre-combustion chamber, a post-combustion chamber and a circulation decomposition chamber which are sequentially connected from bottom to top, and a constriction structure is formed at the interface between the pre-combustion chamber and the post-combustion chamber and at the interface between the post-combustion chamber and the circulation decomposition chamber.

[0027] Furthermore, it also includes a circulation separator, the inlet of the circulation separator is connected to the outlet at the top of the circulation decomposition chamber, and the discharge port at the bottom of the circulation separator is connected to the circulation decomposition chamber.

[0028] Beneficial effects of the present invention:

[0029] The carbon dioxide enrichment device under pure oxygen combustion provided by the present invention comprises a decomposition furnace and an air-fuel mechanism; a fuel gas injection port is arranged at the bottom of the decomposition furnace; the air-fuel mechanism comprises an air-fuel shell and a pure oxygen air distributor, wherein: an air-fuel chamber is arranged inside the air-fuel shell, and the outlet of the air-fuel chamber is connected with the fuel gas injection port; the pure oxygen air distributor is arranged at the bottom of the air-fuel chamber, and the inlet of the pure oxygen air distributor is used for inputting oxygen, and the pure oxygen air distributor has a plurality of outlets which are distributed at intervals along the circumference and connected with the air-fuel chamber.

[0030] Since the pure oxygen air distributor has multiple outlets spaced apart along the circumferential direction, the pure oxygen air distributor can evenly distribute oxygen, so that oxygen can disperse into the air-combustion chamber; the oxygen in the air-combustion chamber can disperse into the decomposition furnace, so that oxygen can fully contact with coal powder and raw meal, improving the combustion efficiency and the decomposition effect of the raw meal. In addition, the pure oxygen air distributor is arranged at the bottom of the air-combustion chamber, and the oxygen sprayed from the pure oxygen air distributor forms a bubbling air cushion layer at the bottom of the air-combustion chamber. The bubbling air cushion layer can prevent high-temperature powder from being deposited at the bottom of the air-combustion chamber, thereby ensuring the normal operation of the air-combustion mechanism. In addition, during production, there may be a small amount of sintered granular material at the bottom of the air-combustion chamber. The high-speed airflow sprayed by the pure oxygen air distributor can penetrate the sintered granular material from bottom to top, ensuring that the production process can be carried out stably. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 A schematic diagram of the structure of a carbon dioxide enrichment device under pure oxygen combustion provided in an embodiment of the present invention;

[0033] Figure 2 A schematic diagram of the structure of an air-fuel mechanism provided in an embodiment of the present invention;

[0034] Figure 3 for Figure 2 A schematic cross-sectional view at AA;

[0035] Figure 4 A schematic diagram of an axial cross section of a first nozzle provided in an embodiment of the present invention;

[0036] Figure 5 for Figure 2 A schematic cross-sectional view at BB;

[0037] Figure 6 An axial cross-sectional schematic diagram of a first burner provided in an embodiment of the present invention;

[0038] Figure 7 for Figure 2 A schematic cross-sectional view at CC;

[0039] Figure 8 A schematic diagram of the structure of a decomposition furnace, an air-fuel mechanism, a circulation separator and a raw material feeding mechanism provided in an embodiment of the present invention;

[0040] Fig. 9for Figure 8 A schematic cross-sectional view at DD;

[0041] Fig.10 An axial cross-sectional schematic diagram of a second burner provided in an embodiment of the present invention;

[0042] Fig.11 for Figure 8 Enlarged view at E;

[0043] Fig.12 for Fig.10 Schematic cross-sectional view at FF.

[0044] icon:

[0045] 100-calciner; 110-gas injection port; 120-raw material feed box; 130-pre-combustion chamber; 140-afterburning chamber; 150-circulation decomposition chamber;

[0046] 200-air-combustion mechanism; 210-air-combustion shell; 211-air-combustion chamber; 220-pure oxygen air distributor; 230-first burner; 231-fuel spray gun; 232-first pulverized coal channel; 233-first oxygen channel; 234-circulating gas channel; 240-circulating gas air distributor; 250-slag discharge channel; 260-first nozzle; 270-third nozzle;

[0047] 300-annular oxygenator; 310-second nozzle;

[0048] 400-second burner; 410-second pulverized coal channel; 420-second oxygen channel; 430-dispersing sheet;

[0049] 500-circulation separator;

[0050] 600-dust removal and cooling mechanism;

[0051] 700-raw material feeding mechanism; 710-raw material bin; 720-raw material weighing scale;

[0052] 800-coal powder feeding mechanism; 810-coal powder bin; 820-coal powder weighing scale;

[0053] 900-pure oxygen delivery pipeline; 910-delivery main pipe; 920-delivery branch pipe. DETAILED DESCRIPTION

[0054] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] It should be noted that in the description of the present invention, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0056] It should be noted that in the description of the present invention, the terms "connection" and "installation" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or connected through an intermediate medium; it can be a mechanical connection or an electrical connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0057] The existing device for carbon capture using pure oxygen combustion process only has one oxygen inlet at the bottom of the decomposition furnace. Under this structure, the oxygen entering the decomposition furnace is difficult to fully diffuse, resulting in the inability of oxygen to fully contact the raw material, thereby affecting the decomposition effect of the raw material.

[0058] Based on this, the embodiment of the present invention provides a carbon dioxide enrichment device under pure oxygen combustion, referring to Figures 1 to 3 , the device comprises:

[0059] The decomposition furnace 100 has a fuel gas injection port 110 at its bottom;

[0060] The air-fuel mechanism 200 includes an air-fuel shell 210 and a pure oxygen air distributor 220, wherein: an air-fuel chamber 211 is provided inside the air-fuel shell 210, and the outlet of the air-fuel chamber 211 is connected to the gas injection port 110; the pure oxygen air distributor 220 is arranged at the bottom of the air-fuel chamber 211, and the inlet of the pure oxygen air distributor 220 is used to input oxygen. The pure oxygen air distributor 220 has a plurality of outlets distributed at intervals along the circumference and connected to the air-fuel chamber 211.

[0061] The carbonate raw material used in the device provided by the present invention mainly comes from the raw material entering the cement kiln and the hot raw material from the cement burning system. The raw material entering the kiln enters the decomposition furnace 100 for high-temperature decomposition after proportioning, and the hot raw material from the cement burning system enters the decomposition furnace 100 for high-temperature decomposition through the material distribution valve. In addition, the device uses coal powder from the cement kiln system as the main fuel.

[0062] Reference Figure 1 and Figure 2The furnace wall of the decomposition furnace 100 is provided with a raw meal injection port for raw meal and a pulverized coal injection port for pulverized coal. During operation, pulverized coal and raw meal are respectively fed into the decomposition furnace 100 through the pulverized coal injection port and the raw meal injection port, and pure oxygen (oxygen concentration> 99%) enters the air combustion chamber 211 through the pure oxygen air distributor 220; the high-temperature airflow in the air combustion chamber 211 rises and enters the decomposition furnace 100, and is mixed and burned with the pulverized coal and raw meal in the furnace.

[0063] Since the pure oxygen air distributor 220 has a plurality of outlets spaced apart along the circumferential direction, the pure oxygen air distributor 220 can evenly distribute oxygen, so that oxygen can disperse into the air-combustion chamber 211; the oxygen in the air-combustion chamber 211 can disperse into the decomposition furnace 100, so that oxygen can fully contact with raw materials and coal powder, thereby improving the combustion efficiency and the decomposition effect of raw materials. In addition, the pure oxygen air distributor 220 is arranged at the bottom of the air-combustion chamber 211, and the oxygen sprayed from the pure oxygen air distributor 220 forms a bubbling air cushion layer at the bottom of the air-combustion chamber 211. The bubbling air cushion layer can prevent high-temperature powder from being deposited at the bottom of the air-combustion chamber 211, thereby ensuring the normal operation of the air-combustion mechanism 200. In addition, during production, there may be a small amount of sintered granular material at the bottom of the air-combustion chamber 211, and the high-speed airflow sprayed by the pure oxygen air distributor 220 can penetrate the sintered granular material from bottom to top, ensuring that the production process can be carried out stably.

[0064] Reference Figure 2 and Figure 3 In this embodiment, the pure oxygen air distributor 220 is annular, and an annular cavity is formed inside the pure oxygen air distributor 220. An inlet is provided on the side wall of the annular cavity, and 30 outlets are evenly distributed along the circumference on the upper end surface of the annular cavity. Figure 4 A first nozzle 260 is provided at the outlet of each pure oxygen air distributor 220. The first nozzle 260 has a plurality of (specifically 8-10 in this embodiment) spray holes arranged circumferentially. The elevation angle of the spray hole axis relative to the horizontal is 15°, and the wind speed of the spray hole is 50-60 m / s.

[0065] With the above structure, pure oxygen gas enters the pure oxygen air distributor 220 from one side of the pure oxygen air distributor 220, and then is ejected from a plurality of first nozzles 260 and enters the air combustion chamber 211. Since the first nozzles 260 are evenly distributed in an annular shape, and each first nozzle 260 is provided with a plurality of spray holes, the oxygen entering the air combustion chamber 211 forms a relatively uniform spraying gas cushion layer, which not only improves the dispersion of oxygen, but also prevents the deposition of high-temperature powder.

[0066] Continue to refer to Figure 2 and Figure 3 The air-fuel mechanism 200 further includes a slag discharge channel 250, which is located at the bottom of the air-fuel chamber 211 and communicates with the air-fuel chamber 211;

[0067] The pure oxygen air distributor 220 is mounted on the slag discharge channel 250 .

[0068] In this embodiment, an electric regulating valve is provided on the slag discharge channel 250, and the residue in the air-combustion chamber 211 can be discharged by controlling the opening and closing degree of the electric flow regulating valve.

[0069] Continue to refer to Figure 1 The carbon dioxide enrichment device further includes a dust removal and cooling mechanism 600, the inlet of the dust removal and cooling mechanism 600 is connected to the outlet at the top of the decomposition furnace 100 through a pipeline;

[0070] The air combustion chamber 211 is provided with a pure oxygen inlet and a circulating gas inlet. The pure oxygen inlet is connected to the outlet of the pure oxygen air distributor 220, and the circulating gas inlet is connected to the outlet of the dust removal and cooling mechanism 600 through a pipeline.

[0071] The dust removal and cooling mechanism 600 is used to cool and remove dust from the dust-containing gas flow generated by the decomposition furnace 100 to obtain a mixed gas of pure oxygen and high-concentration carbon dioxide. A portion of the mixed gas of pure oxygen and high-concentration carbon dioxide is sent to the liquefaction and purification system, and a portion of the mixed gas of pure oxygen and high-concentration carbon dioxide enters the air-combustion chamber 211 through a pipeline. The above arrangement can, on the one hand, control the temperature in the air-combustion chamber 211 by controlling the input amount of the mixed gas, and on the other hand, it can increase the carbon dioxide concentration in the furnace, providing good conditions for the subsequent capture and purification of carbon dioxide.

[0072] Based on the above structure, refer to Figure 2 and Figure 5 The air-fuel mechanism 200 further includes a first burner 230 and a circulating air blower 240, wherein:

[0073] The first burner 230 is arranged on the end surface where the circulating gas inlet is located, and the outlet end of the first burner 230 extends into the air-combustion chamber 211;

[0074] The circulating air blower 240 is mounted on the first burner 230, and the inlet of the circulating air blower 240 is connected to the outlet of the dust removal cooling mechanism 600 through a pipeline. The circulating air blower 240 is provided with a plurality of outlets distributed at intervals along the circumferential direction. The number of the circulating air inlets is multiple and corresponds one-to-one with the outlets of the circulating air blower 240.

[0075] In the above structure, the circulating gas air distributor 240 can evenly distribute the circulating gas, so that the circulating gas enters the air-combustion chamber 211 in a dispersed manner. The first burner 230 is located at the center of the end face where the circulating gas inlet is located, and the circulating gas air distributor 240 is arranged in a ring shape around the first burner 230. The circulating gas with a lower temperature in the circulating gas air distributor 240 can absorb the local high temperature formed by the combustion of the pulverized coal, thereby protecting the refractory material of the inner wall of the air-combustion chamber 211.

[0076] Further, a third nozzle 270 is provided at each outlet of the circulating air distributor 240. The structure of the third nozzle 270 can refer to the structure of the first nozzle 260. Of course, it can also be a common nozzle, which is not limited here. In this embodiment, the circulating air distributor 240 is arranged with 6-8 third nozzles 270 along the annular direction, and the depth of the third nozzle 270 inserted into the air-combustion chamber 211 is 200-300 mm.

[0077] Reference Figure 6 The first burner 230 includes a fuel spray gun 231, a first pulverized coal channel 232, a first oxygen channel 233 and a circulating gas channel 234 which are sequentially mounted from the inside to the outside. The inlet of the circulating gas channel 234 is connected to the outlet of the dust removal cooling mechanism 600 through a pipeline.

[0078] Among them, the fuel spray gun 231 is used for ignition and supplementary combustion; the first pulverized coal channel 232 can heat the circulating gas in the circulating gas channel 234 to 900-1200°C, and the wind speed in the first pulverized coal channel 232 is preferably 20-24m / s; the first oxygen channel 233 inputs a small amount of pure oxygen gas through the pipeline and the electric valve on the pipeline to reduce the ignition temperature of the pulverized coal and increase the combustion temperature. The wind speed in the first oxygen channel 233 is preferably 10-15m / s; the circulating gas channel 234 inputs a small amount of circulating gas through the pipeline and the electric valve on the pipeline to absorb the heat in the first burner 230 area, protect the first burner 230 and control the combustion temperature. The wind speed in the circulating gas channel 234 is preferably 10-20m / s.

[0079] Reference Figure 2 and Figure 7 The air-fuel casing 210 is a volute structure, and includes a main pipe extending in a spiral shape and an air intake end plate arranged at the end of the main pipe. A pure oxygen inlet is provided at the bottom of the main pipe, and a circulating gas inlet is provided on the air intake end plate.

[0080] Specifically, the air-fuel shell 210 adopts a three-stage volute structure, and the initial volute variable distance is 0.2D. The first burner 230 and the circulating gas air distributor 240 are both installed on the air inlet end plate of the air-fuel shell 210. The bottom of the air-fuel shell 210 is provided with a plurality of pure oxygen inlets distributed in an annular pattern, and the pure oxygen inlets correspond to and are connected with the outlets of the pure oxygen air distributor 220 one by one. An outlet is provided at the center of the top of the air-fuel shell 210, and the outlet is connected with the gas injection port 110 at the bottom of the decomposition furnace 100.

[0081] By adopting the above-mentioned air-combustion shell 210 structure, during operation, the combustion and heating airflow in the air-combustion chamber 211 is swirled by the system draft, which prolongs the pulverized coal combustion time and is beneficial to the uniformity of the airflow composition and temperature in the air-combustion chamber 211.

[0082] Reference Figure 8 The decomposition furnace 100 is provided with a pre-combustion chamber 130, a post-combustion chamber 140 and a circulation decomposition chamber 150 which are sequentially connected from bottom to top. The interface between the pre-combustion chamber 130 and the post-combustion chamber 140 and the interface between the post-combustion chamber 140 and the circulation decomposition chamber 150 form a constriction structure. Figure 8 As shown, the pre-combustion chamber 130, the after-combustion chamber 140 and the circulating decomposition chamber 150 form a three-stage contraction structure. The wind speed at the contraction can reach 20-30m / s, thereby improving the dispersion and suspension ability of the material, avoiding the material from settling into the air-combustion chamber 211 and causing sintering, and facilitating better dispersion, suspension and heat exchange of the incoming raw materials.

[0083] On the basis of the above structure, the carbon dioxide enrichment device further includes a circulation separator 500, the inlet of the circulation separator 500 is connected to the outlet at the top of the circulation decomposition chamber 150, and the discharge port at the bottom of the circulation separator 500 is connected to the circulation decomposition chamber 150. The raw material deposited at the bottom of the circulation separator 500 can be returned to the circulation decomposition chamber 150 for further decomposition.

[0084] Continue to refer to Figure 8 The carbon dioxide enrichment device further includes one or more annular oxygenators 300, which are mounted on the decomposition furnace 100. The inlet of the annular oxygenator 300 is used to input oxygen. The annular oxygenator 300 is provided with a plurality of outlets spaced apart along the circumference and connected to the decomposition furnace 100. The function of the annular oxygenator 300 is to supplement oxygen into the decomposition furnace 100 to avoid insufficient combustion due to insufficient oxygen during the combustion process. The annular oxygenator 300 has a plurality of outlets distributed in an annular shape, so that oxygen can be dispersed into the decomposition furnace 100.

[0085] It should be noted that the number of the annular oxygenator 300 can be one or more. When the number of the annular oxygenator 300 is multiple, the multiple annular oxygenators 300 are distributed at intervals along the axial direction of the decomposition furnace 100. In this embodiment, the number of the annular oxygenators 300 is two, and they are respectively mounted on the outside of the pre-combustion chamber 130 and the after-combustion chamber 140.

[0086] Reference Fig. 9 , a second nozzle 310 is provided at each outlet of the annular oxygenator 300, and the plurality of second nozzles 310 are arranged in a tangential rotary cutting manner; the arrangement rotation direction of the plurality of second nozzles 310 is the same as the rotation direction of the air-fuel shell 210. The tangential rotary cutting arrangement means that the extension lines of the axes of the plurality of second nozzles 310 are tangent to the same reference circle. In this embodiment, the reference circle is arranged concentrically with the decomposition furnace 100, and the diameter of the reference circle is 0.3 times the inner diameter of the decomposition furnace 100. The wind speed of the second nozzle 310 is preferably 20-25m / s. The airflow rigidity at this wind speed is better, which is conducive to the uniform dispersion and penetration of oxygen.

[0087] Continue to refer to Figure 8 and Fig.10 The carbon dioxide enrichment device further comprises a plurality of second burners 400, which are mounted on the side wall of the decomposition furnace 100 and whose outlet ends extend into the decomposition furnace 100;

[0088] The second burner 400 includes a second pulverized coal passage 410 and a second oxygen passage 420 .

[0089] It should be noted that the number of the second burners 400 is one or more; when the number of the second burners 400 is more than one, the plurality of second burners 400 may be arranged at intervals on the side wall of the decomposition furnace 100. In this embodiment, one second burner 400 is arranged on opposite sides of the pre-combustion chamber 130, and one second burner 400 is arranged on the after-combustion chamber 140.

[0090] Reference Figure 8 , Fig.11 and Fig.12 A plurality of raw material feed boxes 120 are provided on the side wall of the decomposition furnace 100 , wherein one or more of the raw material feed boxes 120 are provided with a second burner 400 .

[0091] And / or, a hollow-shaped scattering sheet 430 is laid at the outlet of the second pulverized coal channel 410 .

[0092] In the above structure, the raw material feed box 120 is fixed on the side wall of the decomposition furnace 100, and is used to input raw materials (which can be hot raw materials from the cement burning system or raw materials entering the cement kiln) into the decomposition furnace 100.

[0093] It should be noted that the number of the raw material feed boxes 120 is one or more; when the number of the raw material feed boxes 120 is more than one, the multiple raw material feed boxes 120 can be arranged at intervals on the side wall of the decomposition furnace 100 so that the raw material can be dispersed and enter the decomposition furnace 100. The second burner 400 can be installed on only one or more of the raw material feed boxes 120. Whether to install the second burner 400 on the raw material feed box 120 needs to be adjusted according to actual conditions, and is not limited here.

[0094] In this embodiment, a raw material feed box 120 is arranged on opposite sides of the pre-combustion chamber 130, and a second burner 400 is provided on the raw material feed box 120 at the pre-combustion chamber 130. A raw material feed box 120 is arranged on the afterburning chamber 140 and the circulating decomposition chamber 150, respectively, wherein the raw material feed box 120 on the circulating decomposition chamber 150 is connected to the circulating separator 500 through a pipeline.

[0095] Reference Fig.11 and Fig.12In this embodiment, the second burner 400 is a double-channel nested structure. The second pulverized coal channel 410 is arranged on the inner side, and its pipeline wind speed is preferably 20m / s; the end of the second pulverized coal channel 410 is provided with a Y-shaped scattering piece 430, which can disperse the airflow and scatter the raw material entering the decomposition furnace 100, play the role of scattering and mixing pulverized coal and raw material, and reduce the risk of high-temperature sintering. The second oxygen channel 420 is arranged on the outer side, and its pipeline wind speed is preferably 25m / s. The second burner 400 can be inserted from the back of the raw material feed box 120 (i.e., the side away from the furnace wall of the decomposition furnace 100), and it protrudes 100-200mm from the surface of the refractory material on the furnace wall of the decomposition furnace 100.

[0096] Continue to refer to Figure 1 The carbon dioxide enrichment device provided in this embodiment also includes:

[0097] The raw material feeding mechanism 700 includes a raw material bin 710 and a raw material weighing scale 720, wherein the raw material bin 710 is used to store raw materials, the inlet of the raw material weighing scale 720 is connected to the outlet at the bottom of the raw material bin 710, and the outlet of the raw material weighing scale 720 is respectively connected to the pre-combustion chamber 130 and the after-combustion chamber 140 through pipelines;

[0098] The pulverized coal feeding mechanism 800 includes a pulverized coal bin 810 and a pulverized coal weighing scale 820, wherein the pulverized coal bin 810 is used to store pulverized coal, the inlet of the pulverized coal weighing scale 820 is connected to the outlet at the bottom of the pulverized coal bin 810, and the outlet of the pulverized coal weighing scale 820 is respectively connected to the first pulverized coal channel 232 of the first burner 230 and the second pulverized coal channel 410 of each second burner 400 through pipelines;

[0099] The pure oxygen delivery pipeline 900 includes a delivery main pipe 910 and a delivery branch pipe 920. There are multiple delivery branch pipes 920. A delivery branch pipe 920 is connected between the pure oxygen air distributor 220 and the delivery main pipe 910, a delivery branch pipe 920 is connected between each annular oxygenator 300 and the delivery main pipe 910, and a delivery branch pipe 920 is connected between the oxygen channel of each burner and the delivery main pipe 910 (indicated by lines in the figure).

[0100] The above structure forms a conveying route for raw meal, coal powder and oxygen.

[0101] On the basis of the above structure, an electric regulating valve is provided on each pipeline. In the actual working process, the opening and closing degree of the electric regulating valve is controlled according to the equipment metering and process system control needs, so that the raw material, coal powder and oxygen enter the air combustion chamber 211, the pre-combustion chamber 130 and the after-combustion chamber 140 in the required proportion. The bottom of the pre-combustion chamber 130 also has a constricted structure, and a gas analyzer is provided at the constricted structure at the bottom of the pre-combustion chamber 130. By adjusting the amount of pure oxygen entering the air combustion chamber 211 through the electric regulating valve, the oxygen content of the high-temperature gas entering the pre-combustion chamber 130 is ensured to be 18% to 26%; a gas analyzer is provided at the outlet of the circulating decomposition chamber 150, and by adjusting the amount of pure oxygen entering the air combustion chamber 211 through the electric valve, the oxygen content after combustion is ensured to be less than 10%; at the same time, temperature sensors are provided in the air combustion chamber 211, the pre-combustion chamber 130, the after-combustion chamber 140 and the circulating decomposition chamber 150, respectively, for detecting the temperature of each area, so as to facilitate the control of process parameters.

[0102] As an optional embodiment, the temperature of the air combustion chamber 211 is controlled at 900-1200°C, the temperature of the pre-combustion chamber 130 is controlled at 900-1050°C, the temperature of the afterburning chamber 140 is controlled at 900-1000°C, and the temperature of the circulating decomposition chamber 150 is controlled at 900-950°C.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A carbon dioxide enrichment device under pure oxygen combustion, characterized in that: include: A decomposition furnace (100) having a fuel gas injection port (110) disposed at the bottom thereof; An air-fuel mechanism (200) comprises an air-fuel shell (210) and a pure oxygen air distributor (220), wherein: an air-fuel chamber (211) is provided inside the air-fuel shell (210), and an outlet of the air-fuel chamber (211) is communicated with the fuel gas injection port (110); the pure oxygen air distributor (220) is arranged at the bottom of the air-fuel chamber (211), and an inlet of the pure oxygen air distributor (220) is used for inputting oxygen, and the pure oxygen air distributor (220) has a plurality of outlets which are distributed at intervals along the circumferential direction and communicated with the air-fuel chamber (211).

2. The carbon dioxide enrichment device under pure oxygen combustion according to claim 1, characterized in that: It also includes a dust removal and cooling mechanism (600), wherein the inlet of the dust removal and cooling mechanism (600) is connected to the outlet at the top of the decomposition furnace (100) through a pipeline; The air-combustion chamber (211) is provided with a pure oxygen inlet and a circulating gas inlet. The pure oxygen inlet is connected to the outlet of the pure oxygen air distributor (220), and the circulating gas inlet is connected to the outlet of the dust removal and cooling mechanism (600) through a pipeline.

3. The carbon dioxide enrichment device under pure oxygen combustion according to claim 2, characterized in that: The air-fuel mechanism (200) further comprises a first burner (230) and a circulating air blower (240), wherein: The first burner (230) is arranged on the end surface where the circulating gas inlet is located, and the outlet end of the first burner (230) extends into the air-combustion chamber (211); The circulating air blower (240) is mounted on the first burner (230), and the inlet of the circulating air blower (240) is connected to the outlet of the dust removal cooling mechanism (600) through a pipeline. The circulating air blower (240) is provided with a plurality of outlets spaced apart along the circumferential direction, and the number of the circulating air inlets is multiple and corresponds one-to-one with the outlets of the circulating air blower (240).

4. The carbon dioxide enrichment device under pure oxygen combustion according to claim 3, characterized in that: The first burner (230) comprises a fuel spray gun (231), a first coal powder channel (232), a first oxygen channel (233) and a circulating gas channel (234) which are sequentially mounted from the inside to the outside, and an inlet of the circulating gas channel (234) is connected to an outlet of the dust removal and cooling mechanism (600) via a pipeline.

5. The carbon dioxide enrichment device under pure oxygen combustion according to claim 2, characterized in that: The air-fuel casing (210) is a volute structure, comprising a main pipe extending in a spiral shape and an air intake end plate arranged at the end of the main pipe, the bottom of the main pipe is provided with the pure oxygen inlet, and the air intake end plate is provided with the circulating gas inlet.

6. The carbon dioxide enrichment device under pure oxygen combustion according to claim 5, characterized in that: It also includes one or more annular oxygenators (300), which are mounted on the decomposition furnace (100). The inlet of the annular oxygenator (300) is used to input oxygen. The annular oxygenator (300) is provided with a plurality of outlets which are distributed at intervals along the circumference and connected to the decomposition furnace (100).

7. The carbon dioxide enrichment device under pure oxygen combustion according to claim 6, characterized in that: A second nozzle (310) is disposed at each outlet of the annular oxygenator (300), and a plurality of the second nozzles (310) are arranged in a cutting rotary cutting manner; The arrangement rotation direction of the plurality of second nozzles (310) is the same as the rotation direction of the air-fuel casing (210).

8. The carbon dioxide enrichment device under pure oxygen combustion according to claim 1, characterized in that: The air-fuel mechanism (200) further comprises a slag discharge channel (250), wherein the slag discharge channel (250) is located at the bottom of the air-fuel chamber (211) and is in communication with the air-fuel chamber (211); The pure oxygen air distributor (220) is mounted on the slag discharge channel (250).

9. The carbon dioxide enrichment device under pure oxygen combustion according to claim 1, characterized in that: It also includes a plurality of second burners (400), wherein the second burners (400) are installed on the side wall of the decomposition furnace (100) and the outlet ends thereof extend into the decomposition furnace (100); The second burner (400) includes a second pulverized coal channel (410) and a second oxygen channel (420).

10. The carbon dioxide enrichment device under pure oxygen combustion according to claim 9, characterized in that: A plurality of raw material feed boxes (120) are provided on the side wall of the decomposition furnace (100), wherein the second burner (400) is installed on one or more of the raw material feed boxes (120); And / or, a hollow-shaped scattering sheet (430) is laid at the outlet of the second coal powder channel (410).

11. The carbon dioxide enrichment device under pure oxygen combustion according to any one of claims 1 to 10, characterized in that: The decomposition furnace (100) is provided with a pre-combustion chamber (130), an after-combustion chamber (140) and a circulation decomposition chamber (150) which are sequentially connected from bottom to top, and a constriction structure is formed at the interface between the pre-combustion chamber (130) and the after-combustion chamber (140) and at the interface between the after-combustion chamber (140) and the circulation decomposition chamber (150).

12. The carbon dioxide enrichment device under pure oxygen combustion according to claim 11, characterized in that: It also includes a circulation separator (500), the inlet of the circulation separator (500) is connected to the outlet at the top of the circulation decomposition chamber (150), and the discharge port at the bottom of the circulation separator (500) is connected to the circulation decomposition chamber (150).

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