Ammonia combustion system

Abstract

This invention relates to an ammonia combustion system, comprising: a raw material supply device, a combustion unit, a heat exchange unit, a scrubbing unit, and an evaporation recovery unit. The raw material supply device includes an oxygen supply unit and an ammonia supply unit. The combustion unit is connected to both the oxygen and ammonia supply units. The oxygen supply unit supplies oxygen to the combustion unit, and the ammonia supply unit supplies ammonia to the combustion unit. The heat exchange unit is connected to the combustion unit and converts the hot flue gas discharged from the combustion unit into cold flue gas. The scrubbing unit is connected to both the heat exchange unit and the evaporation recovery unit and scrubs the cold flue gas to separate it into recovered ammonia water and clean flue gas. The evaporation recovery unit evaporates the recovered ammonia water to form recovered ammonia gas and is connected to the combustion unit to introduce the recovered ammonia gas into the combustion unit. This ammonia combustion system can improve ammonia utilization.

Description

Technical Field

[0001] This invention relates to the field of combustion system technology, and more specifically, to an ammonia combustion system. Background Technology

[0002] In the context of low-carbon development, green new energy sources are gaining momentum. Wind and solar power generation capacities are affected by environmental factors, necessitating energy storage technologies. Green energy production through hydrogen and ammonia production represents one direction for energy storage development. While hydrogen storage and transportation costs are high, ammonia storage and transportation costs are relatively low, making ammonia a more promising option. The complete combustion of ammonia produces N2 and H2O, exhibiting high volumetric energy density and requiring only 0.7-0.8 MPa at room temperature for liquefaction, facilitating storage and transportation.

[0003] However, in related technologies, the design of the ammonia combustion system is unreasonable, resulting in insufficient combustion and recovery of ammonia, which reduces the utilization rate of ammonia. Summary of the Invention

[0004] The present invention aims to at least partially solve one of the technical problems in the related art.

[0005] Therefore, embodiments of the present invention propose an ammonia combustion system that can improve the utilization rate of ammonia.

[0006] An ammonia combustion system according to an embodiment of the present invention includes: a raw material supply device, the raw material supply device including an oxygen supply unit and an ammonia supply unit; a combustion unit, the combustion unit being connected to the oxygen supply unit and the ammonia supply unit, the oxygen supply unit being used to supply oxygen to the combustion unit, and the ammonia supply unit being used to supply ammonia to the combustion unit; a heat exchange unit, the heat exchange unit being connected to the combustion unit, the heat exchange unit being used to exchange heat for cold flue gas discharged from the combustion unit; a scrubbing unit and an evaporation recovery unit, the scrubbing unit being connected to the heat exchange unit and the evaporation recovery unit, the scrubbing unit being used to scrub the cold flue gas to separate the cold flue gas into recovered ammonia water and clean flue gas, the evaporation recovery unit being used to evaporate the recovered ammonia water to form recovered ammonia gas, the evaporation recovery unit being connected to the combustion unit to introduce the recovered ammonia gas into the combustion unit.

[0007] According to an embodiment of the present invention, the ammonia combustion system can supply oxygen and ammonia to the combustion system through an oxygen supply unit and an ammonia supply unit, respectively. The heat exchange system is used to exchange heat with the hot flue gas in the combustion unit to recover and utilize the heat. Furthermore, the ammonia in the cold flue gas is recovered through a scrubbing unit and an evaporation recovery unit and reintroduced into the combustion unit to ensure that the ammonia can be fully combusted and utilized, thereby improving the utilization rate of ammonia.

[0008] In some embodiments, the ammonia supply unit includes a liquid ammonia storage unit and a vaporization unit. The liquid ammonia storage unit is connected to the vaporization unit, and the vaporization unit is connected to the combustion unit. The liquid ammonia storage unit is used to supply liquid ammonia to the vaporization unit, and the vaporization unit is used to vaporize the liquid ammonia into ammonia gas.

[0009] In some embodiments, the heat exchange unit has a first cold working fluid line and a first hot working fluid line, both of which are connected to the vaporization unit to provide energy for the vaporization of the liquid ammonia.

[0010] In some embodiments, the heat exchange unit has a second cold working fluid pipeline and a second hot working fluid pipeline, both of which are connected to the evaporation recovery unit to provide energy for the evaporation of the recovered ammonia water.

[0011] In some embodiments, a spray water pipeline is provided between the evaporation recovery unit and the rinsing unit, and the spray water pipeline can return the spray water in the evaporation recovery unit to the rinsing unit.

[0012] In some embodiments, the ammonia combustion system further includes an emission unit connected to the scrubbing unit, the emission unit being used to treat the clean flue gas and discharge it into the atmosphere.

[0013] In some embodiments, the combustion unit includes a boiler, a shell, and an ejector. The shell is located outside the boiler and has an ammonia inlet, an air inlet, a flue gas inlet, and a discharge port. A reaction chamber is located inside the shell. The flue gas inlet and the discharge port are both connected to the furnace of the boiler. The ejector is located inside the reaction chamber and has an inlet end, an outlet end, and a suction end. The ammonia inlet is connected to the inlet end, the suction end is connected to the flue gas inlet, and the outlet end and the air inlet are connected to the discharge port through the reaction chamber.

[0014] In some embodiments, there are multiple ejectors, which are spaced apart within the reaction chamber. The reaction chamber includes an ammonia distribution chamber, which is connected to the ammonia interface and the inlet ends of the multiple ejectors.

[0015] In some embodiments, the reaction chamber further includes a high-temperature flue gas chamber, which is independent of the ammonia distribution chamber. The flue gas inlet is connected to the inhalation end through the high-temperature flue gas chamber, and at least a portion of the ejector tube is located in the high-temperature flue gas chamber.

[0016] In some embodiments, the reaction chamber is provided with a first partition and a second partition. The first partition and the side wall of the housing define the ammonia distribution chamber. The high-temperature flue gas chamber is defined between the first partition and the second partition. The ejector includes a first pipe section and a second pipe section. A first end of the first pipe section passes through the first partition and extends into the ammonia distribution chamber. A second end of the first pipe section passes through the second partition and communicates with the first end of the second pipe section. The first end of the first pipe section constitutes the inlet end. The first end of the second pipe section constitutes the suction end. The second end of the second pipe section constitutes the outlet end.

[0017] In some embodiments, the inhalation end is arranged to gradually narrow along the direction from the first end of the second tube segment to the second end of the second tube segment, the first end of the second tube segment is connected to the second partition, and the first tube segment and the second tube segment are arranged coaxially.

[0018] In some embodiments, the reaction chamber further includes an air chamber and a premixing chamber. The air inlet is connected to the air chamber, and the outlet is connected to the discharge port through the premixing chamber. An air distribution plate is provided between the air chamber and the premixing chamber. A plurality of ventilation holes are arranged at intervals on the air distribution plate, and the air chamber is connected to the premixing chamber through the ventilation holes. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of an ammonia combustion system according to an embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of the combustion unit of the ammonia combustion system according to an embodiment of the present invention.

[0021] Figure label:

[0022] 1. Raw material supply unit; 11. Oxygen supply unit; 12. Ammonia supply unit; 121. Liquid ammonia storage unit; 122. Gasification unit;

[0023] 2. Combustion unit; 21. Boiler; 211. Furnace; 22. Shell; 221. Ammonia inlet; 222. Air inlet; 223. Flue gas inlet; 224. Discharge port; 225. Reaction chamber; 2251. Ammonia distribution chamber; 2252. High-temperature flue gas chamber; 2523. Air chamber; 2524. Premixing chamber; 226. First baffle; 227. Second baffle; 228. Air distribution plate; 2281. Ventilation hole; 229. Flue pipe; 23. Ejector; 231. First pipe section; 2311. Inlet end; 232. Second pipe section; 2321. Suction end; 2322. Outlet end;

[0024] 3. Heat exchange unit; 31. First cold working fluid pipeline; 32. First hot working fluid pipeline; 33. Second cold working fluid pipeline; 34. Second hot working fluid pipeline; 35. User end;

[0025] 4. Shower unit;

[0026] 5. Evaporation and recovery unit;

[0027] 6. Emission unit. Detailed Implementation

[0028] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0029] The following is a reference appendix. Figure 1 and Figure 2 A combustion system for ammonia gas according to an embodiment of the present invention is described.

[0030] like Figure 1 As shown, the ammonia combustion system according to an embodiment of the present invention includes: a raw material supply device 1, a combustion unit 2, a heat exchange unit 3, a scrubbing unit 4, and an evaporation recovery unit 5. The raw material supply device 1 includes an oxygen supply unit 11 and an ammonia supply unit 12.

[0031] Combustion unit 2 is connected to oxygen supply unit 11 and ammonia supply unit 12. Oxygen supply unit 11 supplies oxygen to combustion unit 2, and ammonia supply unit 12 supplies ammonia to combustion unit 2. Heat exchange unit 3 is connected to combustion unit 2 and is used to exchange the hot flue gas discharged from combustion unit 2 into cold flue gas. Washing unit 4 is connected to heat exchange unit 3 and evaporation recovery unit 5. Washing unit 4 is used to wash the cold flue gas to separate it into recovered ammonia water and clean flue gas. Evaporation recovery unit 5 is used to evaporate the recovered ammonia water to form recovered ammonia gas. Evaporation recovery unit 5 is connected to combustion unit 2 to introduce the recovered ammonia gas into combustion unit 2.

[0032] According to an embodiment of the present invention, the ammonia combustion system can supply oxygen and ammonia to the combustion system through the oxygen supply unit 11 and the ammonia supply unit 12 respectively. The heat exchange system is used to exchange heat with the hot flue gas in the combustion unit 2 to recover and utilize the heat. The ammonia in the cold flue gas is recovered through the scrubbing unit 4 and the evaporation recovery unit 5 and then reintroduced into the combustion unit 2 to ensure that the ammonia can be fully combusted and utilized, thereby improving the utilization rate of ammonia.

[0033] Understandably, the oxygen supply unit 11 can also supply air with a lower oxygen content to the combustion unit 2, thereby utilizing the principle that ammonia burns under low oxygen conditions and that the NO concentration in the flue gas is low, reducing the NO content in the flue gas and improving the combustion effect.

[0034] Within combustion unit 2, air from oxygen supply unit 11, ammonia from ammonia supply unit 12, and recovered ammonia from evaporation and recovery unit 5 are mixed and combusted to generate hot flue gas with N2 and H2O as the main products. The low oxygen content in combustion unit 2 ensures that the flue gas contains a suitable concentration of ammonia. This results in extremely low NO concentrations during combustion, eliminating the need for a separate denitrification system to treat NO in the flue gas. The low-concentration ammonia in the flue gas is recovered and reused in the subsequent scrubbing unit 4, thereby improving ammonia utilization.

[0035] Optionally, the ammonia supply unit 12 includes a liquid ammonia storage unit 121 and a vaporization unit 122. The liquid ammonia storage unit 121 is connected to the vaporization unit 122, and the vaporization unit 122 is connected to the combustion unit 2. The liquid ammonia storage unit 121 supplies liquid ammonia to the vaporization unit 122, and the vaporization unit 122 vaporizes the liquid ammonia into ammonia gas. It is understood that the liquid ammonia storage unit 121 stores the transported liquid ammonia. Depending on actual needs, the liquid ammonia storage unit 121 can supply liquid ammonia to the vaporization unit 122, which then vaporizes the ammonia before introducing it into the combustion unit 2. The ammonia combustion system of this embodiment of the invention, by configuring the ammonia supply unit with the above structure, facilitates ammonia storage and is convenient to use.

[0036] Optionally, the heat exchange unit 3 has a first cold working fluid pipeline 31 and a first hot working fluid pipeline 32, both of which are connected to the gasification unit 122, thereby providing energy for the gasification of liquid ammonia. It is understood that the heat exchange unit 3 has a hot working fluid main pipe and a cold working fluid main pipe, through which the gasification unit 122 or the user end 35 can introduce cold working fluid into the heat exchange unit 3. Furthermore, the heat exchange unit 3 can introduce hot working fluid into the gasification unit 122 or the user end 35 through the hot working fluid main pipe, thereby fully utilizing the heat within the heat exchange unit 3 and improving the energy utilization rate of the ammonia combustion system.

[0037] Optionally, the heat exchange unit 3 has a second cold working fluid pipeline 33 and a second hot working fluid pipeline 34, both of which are connected to the evaporation recovery unit 5, thereby providing energy for the evaporation of recovered ammonia. It is understood that the evaporation recovery unit 5 can introduce a cold working fluid into the heat exchange unit 3 through the second cold working fluid pipeline 33, and the heat exchange unit 3 can introduce a hot working fluid into the evaporation recovery unit 5 through the second hot working fluid pipeline 34, to fully utilize the heat within the heat exchange unit 3 and improve the energy utilization rate of the ammonia combustion system.

[0038] It is understandable that the heat exchange unit 3 exchanges heat between the hot flue gas from the combustion unit 2 and the cold working fluid from the user end 35, the liquid ammonia vaporization unit 122, the evaporation recovery unit 5, etc. The cold flue gas after heat exchange goes to the scrubbing unit 4, and the hot working fluid after heat exchange goes to the user end 35, the vaporization unit 122, the evaporation recovery unit 5, etc.

[0039] In some embodiments, a spray water pipeline is provided between the evaporation recovery unit 5 and the rinsing unit 4. The spray water pipeline can return the spray water in the evaporation recovery unit 5 to the rinsing unit 4 to recycle the spray water and avoid waste of resources.

[0040] In some embodiments, the ammonia combustion system further includes an emission unit 6 connected to a scrubbing unit 4. The emission unit 6 is used to treat the clean flue gas and discharge it into the atmosphere. It is understood that the scrubbing unit 4 washes the cold flue gas with sprayed water, absorbing a small amount of unburned ammonia in the flue gas to form low-concentration ammonia water. The low-concentration ammonia water is sent to the evaporation recovery unit 5, and the clean flue gas after scrubbing is discharged into the atmosphere through the emission unit 6 to avoid environmental pollution.

[0041] In some embodiments, such as Figure 2 As shown, combustion unit 2 is an ammonia burner. Combustion unit 2 (i.e., ammonia burner) includes a boiler 21, a shell 22, and an ejector 23. The shell 22 is located outside the boiler 21. The shell 22 is provided with an ammonia inlet 221, an air inlet 222, a flue gas inlet 223, and a discharge port 224. The shell 22 is provided with a reaction chamber 225. The flue gas inlet 223 and the discharge port 224 are both connected to the furnace 211 of the boiler 21. The ejector 23 is located in the reaction chamber 225. The ejector 23 has an inlet end 2311, an outlet end 2322, and a suction end 2321. The ammonia inlet 221 is connected to the inlet end 2311, the suction end 2321 is connected to the flue gas inlet 223, and the outlet end 2322 and the air inlet 222 are connected to the discharge port 224 through the reaction chamber 225. Specifically, the ammonia supply unit 12 supplies ammonia to the reaction chamber 225 through the ammonia gas interface 221, and the oxygen supply unit 11 supplies air to the reaction chamber 225 through the air interface.

[0042] According to an embodiment of the ammonia combustion system of the present invention, since the ammonia inlet 221 is connected to the inlet end 2311 of the ejector 23, ammonia can be injected into the inlet end 2311 through the ammonia inlet 221. The high-speed injected ammonia generates a negative pressure at the throat of the ejector 23. This negative pressure draws the high-temperature flue gas in the furnace 211 into the ejector 23 and mixes it with the ammonia. At the same time, the air required for ammonia combustion enters the reaction chamber 225 through the air inlet 222 and mixes with the ammonia ejected from the ejector 23, and then enters the furnace 211 together for combustion. Therefore, the combustion unit 2 of the ammonia combustion system of the embodiment of the present invention can premix and heat ammonia and air through the high-temperature flue gas in the furnace 211, reducing the reaction incubation time after ammonia and air enter the furnace 211, and improving the stability of ammonia combustion.

[0043] Understandably, in related technologies, ammonia combustion in air results in slow reaction rates and unstable combustion, leading to low efficiency of the combustion unit 2. This invention proposes a novel combustion unit 2 that utilizes an ejector 23 to draw in high-temperature flue gas from the furnace 211, preheating both ammonia and air during the ammonia-air premixing stage. This combustion unit 2 preheats both ammonia and air by drawing in high-temperature flue gas, increasing their temperatures, reducing ignition incubation time, and improving combustion stability.

[0044] For example, ejector 23 can be a Venturi ejector 23.

[0045] Optionally, multiple ejectors 23 are arranged at intervals within the reaction chamber 225. The reaction chamber 225 includes an ammonia distribution chamber 2251, which is connected to the ammonia inlet 221 and the inlet ends 2311 of the multiple ejectors 23. It is understood that providing multiple ejectors 23 within the reaction chamber 225 can improve the uniformity of the mixing of ammonia and high-temperature flue gas, thereby increasing the reaction rate of the combustion unit 2.

[0046] For example, ejectors 23 are spaced apart in the reaction chamber 225 along the vertical direction of the housing 22, and the front end (inlet end 2311) of the ejector 23 is connected to the ammonia distribution chamber 2251. In this embodiment of the invention, the combustion unit 2 of the ammonia combustion system, by providing the ammonia distribution chamber 2251, can evenly distribute ammonia to each ejector 23 with only one ammonia interface 221 connected to the ammonia distribution chamber 2251, thereby making the ammonia combustion chamber structurally compact and improving its performance.

[0047] In some embodiments, the reaction chamber 225 further includes a high-temperature flue gas chamber 2252, which is independent of the ammonia distribution chamber 2251. The flue gas inlet 223 is connected to the intake end 2321 through the high-temperature flue gas chamber 2252. It is understood that the shell 22 also includes a flue pipe 229. One end of the flue pipe 229 (flue gas inlet 223) is connected to the furnace 211, and the other end of the flue pipe 229 is connected to the high-temperature flue gas chamber 2252. The high-temperature flue gas enters the high-temperature flue gas chamber 2252 along the flue pipe 229, and the high-temperature flue gas in the high-temperature flue gas chamber 2252 can be evenly distributed to each intake end 2321.

[0048] Optionally, at least a portion of the ejector 23 is located within the high-temperature flue gas chamber 2252. It is understood that the outer wall of a portion of the ejector 23 can be heated by the high-temperature flue gas within the high-temperature flue gas chamber 2252 to further increase the temperature of the ammonia and reduce the ignition and incubation time of the ammonia in the furnace 211.

[0049] Specifically, the reaction chamber 225 is provided with a first partition 226 and a second partition 227. The first partition 226 and the side wall of the shell 22 define an ammonia distribution chamber 2251. A high-temperature flue gas chamber 2252 is defined between the first partition 226 and the second partition 227. The ejector 23 includes a first pipe section 231 and a second pipe section 232. The first end of the first pipe section 231 passes through the first partition 226 and extends into the ammonia distribution chamber 2251. The second end of the first pipe section 231 passes through the second partition 227 and communicates with the first end of the second pipe section 232. The first end of the first pipe section 231 constitutes an inlet end 2311. The first end of the second pipe section 232 constitutes an intake end 2321. The second end of the second pipe section 232 constitutes an outlet end 2322. It is understandable that the outer wall of the first tube section 231 of the ejector 23 can be heated by the high-temperature flue gas in the high-temperature flue gas chamber 2252 to increase the temperature of ammonia before combustion. Furthermore, the first partition 226 and the second partition 227 can both support the ejector 23 and separate the reaction chamber 225 into the ammonia distribution chamber 2251 and the high-temperature flue gas chamber 2252, thereby making the structure of the combustion unit 2 more compact and easier to process and manufacture.

[0050] Optionally, the suction end 2321 is in the direction from the first end of the second pipe section 232 to the second end of the second pipe section 232 (e.g., Figure 1 The intake end 2321 gradually narrows from front to back. By adopting the above-described narrowing arrangement of the intake end 2321, the combustion unit 2 of the ammonia combustion system of this embodiment of the invention can guide the high-temperature flue gas into the second pipe section 232, thereby increasing the rate at which the high-temperature flue gas and ammonia enter the second pipe section 232.

[0051] Optionally, the first end of the second pipe section 232 is connected to the second baffle 227, and the first pipe section 231 and the second pipe section 232 are arranged coaxially. It is understood that the second baffle 227 is provided with a channel to communicate with the first end (suction end 2321) of the second pipe section 232, and the first pipe section 231 and the second pipe section 232 are arranged coaxially, which can ensure the uniformity of the mixing of high-temperature flue gas and ammonia, and is beneficial to improving the preheating effect of ammonia.

[0052] In some embodiments, the reaction chamber 225 further includes an air chamber 2523 and a premixing chamber 2524. An air inlet 222 communicates with the air chamber 2523, and an outlet 2322 communicates with the discharge port 224 through the premixing chamber 2524. An air distribution plate 228 is provided between the air chamber 2523 and the premixing chamber 2524. Multiple ventilation holes 2281 are spaced apart on the air distribution plate 228, and the air chamber 2523 communicates with the premixing chamber 2524 through the ventilation holes 2281. It can be understood that air enters the air chamber 2523 through the air inlet 222. Since the air distribution plate 228 has multiple through holes, air can be evenly injected into the premixing chamber 2524 through the multiple ventilation holes 2281. Furthermore, ammonia gas mixed with high-temperature flue gas is also injected into the premixing chamber 2524 through multiple ejectors 23, thereby ensuring the uniformity of the mixing of air, ammonia gas, and high-temperature flue gas and the preheating effect. Finally, the uniformly mixed air, ammonia, and high-temperature flue gas enter the furnace 211 through the discharge port 224, which can reduce the reaction incubation time of ammonia and air after entering the furnace 211 and improve the stability of ammonia combustion.

[0053] Optionally, the shell 22 is arranged to gradually narrow towards the outlet 224. It is understood that because the shell 22 gradually narrows towards the outlet 224, the cross-sectional area of ​​the shell 22 at the outlet 224 gradually decreases from front to back, thereby increasing the rate at which the mixed ammonia enters the furnace 211, and further improving the premixing effect of the ammonia, resulting in better stability of ammonia combustion.

[0054] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0055] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0056] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0057] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0058] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0059] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. An ammonia combustion system, characterized in that, include: A raw material supply device, comprising an oxygen supply unit and an ammonia supply unit; A combustion unit is connected to an oxygen supply unit and an ammonia supply unit. The oxygen supply unit supplies oxygen to the combustion unit, and the ammonia supply unit supplies ammonia to the combustion unit. The combustion unit includes a boiler, a shell, and an ejector. The shell is located outside the boiler and has an ammonia inlet, an air inlet, a flue gas inlet, and a discharge port. A reaction chamber is located inside the shell. The flue gas inlet and the discharge port are both connected to the furnace of the boiler. The ejector is located inside the reaction chamber and has an inlet end, an outlet end, and a suction end. The ammonia inlet is connected to the inlet end, the suction end is connected to the flue gas inlet, and the outlet end and the air inlet are connected to the discharge port through the reaction chamber. A heat exchange unit is connected to the combustion unit and is used to exchange the hot flue gas discharged from the combustion unit into cold flue gas. The unit includes a scrubbing unit and an evaporation recovery unit. The scrubbing unit is connected to the heat exchange unit and the evaporation recovery unit. The scrubbing unit is used to scrub the cold flue gas to separate the cold flue gas into recovered ammonia water and clean flue gas. The evaporation recovery unit is used to evaporate the recovered ammonia water to form recovered ammonia gas. The evaporation recovery unit is connected to the combustion unit to introduce the recovered ammonia gas into the combustion unit.

2. The ammonia combustion system according to claim 1, characterized in that, The ammonia supply unit includes a liquid ammonia storage unit and a vaporization unit. The liquid ammonia storage unit is connected to the vaporization unit, and the vaporization unit is connected to the combustion unit. The liquid ammonia storage unit is used to supply liquid ammonia to the vaporization unit, and the vaporization unit is used to vaporize the liquid ammonia into ammonia gas.

3. The ammonia combustion system according to claim 2, characterized in that, The heat exchange unit has a first cold working fluid pipeline and a first hot working fluid pipeline, both of which are connected to the vaporization unit to provide energy for the vaporization of the liquid ammonia.

4. The ammonia combustion system according to claim 1, characterized in that, The heat exchange unit has a second cold working fluid pipeline and a second hot working fluid pipeline, both of which are connected to the evaporation and recovery unit to provide energy for the evaporation of the recovered ammonia water.

5. The ammonia combustion system according to claim 1, characterized in that, A spray water pipeline is provided between the evaporation recovery unit and the rinsing unit, and the spray water pipeline can return the spray water in the evaporation recovery unit to the rinsing unit.

6. The ammonia combustion system according to claim 1, characterized in that, It also includes an emission unit connected to the scrubbing unit, which is used to treat the clean flue gas and discharge it into the atmosphere.

7. The ammonia combustion system according to any one of claims 1-6, characterized in that, There are multiple ejectors, which are arranged at intervals in the reaction chamber. The reaction chamber includes an ammonia distribution chamber, which is connected to the ammonia interface and the inlet ends of the multiple ejectors.

8. The ammonia combustion system according to claim 7, characterized in that, The reaction chamber also includes a high-temperature flue gas chamber, which is independent of the ammonia distribution chamber. The flue gas inlet is connected to the inhalation end through the high-temperature flue gas chamber, and at least a portion of the ejector tube is located in the high-temperature flue gas chamber.

9. The ammonia combustion system according to claim 8, characterized in that, The reaction chamber is provided with a first partition and a second partition. The first partition and the side wall of the shell define the ammonia distribution chamber. The high-temperature flue gas chamber is defined between the first partition and the second partition. The ejector includes a first pipe section and a second pipe section. The first end of the first pipe section passes through the first partition and extends into the ammonia distribution chamber. The second end of the first pipe section passes through the second partition and communicates with the first end of the second pipe section. The first end of the first pipe section constitutes the inlet end. The first end of the second pipe section constitutes the suction end. The second end of the second pipe section constitutes the outlet end.

10. The ammonia combustion system according to claim 9, characterized in that, The inhalation end is arranged to gradually narrow along the direction from the first end of the second tube section to the second end of the second tube section. The first end of the second tube section is connected to the second partition, and the first tube section and the second tube section are arranged coaxially.

11. The ammonia combustion system according to claim 10, characterized in that, The reaction chamber further includes an air chamber and a premixing chamber. The air inlet is connected to the air chamber, and the outlet is connected to the discharge port through the premixing chamber. An air distribution plate is provided between the air chamber and the premixing chamber. Multiple ventilation holes are arranged at intervals on the air distribution plate, and the air chamber is connected to the premixing chamber through the ventilation holes.

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