Horizontal ammonia coal burner, burning system and corner tangential boiler

Abstract

The invention relates to a horizontal ammonia coal burner, a burning system and a corner tangential boiler, the end, used for stretching into a hearth, of the horizontal ammonia coal burner is provided with a rich-lean pulverized coal nozzle, an ammonia fuel main nozzle and an ammonia fuel peripheral nozzle, and the rich-lean pulverized coal nozzle and the ammonia fuel main nozzle are sequentially and adjacently arranged in the horizontal direction; the other sides of the rich-lean pulverized coal nozzle except the side adjacent to the ammonia fuel main nozzle are surrounded by ammonia fuel peripheral nozzles, and peripheral nozzle adjusting devices used for adjusting the through-flow sectional areas of the ammonia fuel peripheral nozzles are arranged in the ammonia fuel peripheral nozzles. According to the horizontal ammonia coal burner, the ignition stability of ammonia coal mixed gas flow can be remarkably improved, the generation of pollutant NOx can be inhibited, different coal quality and boiler load requirements can be met, different ammonia coal mixed burning atmospheres can be created, the burning organization can be adjusted, and then efficient, low-NOx and low-carbon burning of pulverized coal burning ammonia fuel can be achieved; and stable operation of ammonia-coal mixed combustion under different load working conditions is facilitated.

Description

Technical Field

[0001] This invention relates to the field of boiler technology, and in particular to a horizontal ammonia-coal burner, a combustion system, and a tangentially rounded boiler. Background Technology

[0002] As a supporting and regulating power generation entity in the new power system, coal-fired power plants can partially replace coal combustion for power generation by using green hydrogen and green ammonia. This not only enables large-scale and low-cost absorption of intermittent renewable energy and significantly boosts the growth of the hydrogen energy industry, but also improves combustion efficiency, reduces pollutant emissions, and significantly lowers the carbon emission levels of coal-fired power units.

[0003] However, zero-carbon ammonia (NH3) fuel is a highly efficient hydrogen storage medium with advantages such as high energy density, easy liquefaction and transportation, high safety and zero carbon emissions during combustion. In addition, ammonia fuel can be synthesized from renewable energy sources, making it a truly green and clean energy storage medium, suitable as a zero-carbon alternative fuel for coal-fired boilers.

[0004] However, the ammonia combustion process faces the following technical challenges: (1) High ignition temperature, with an ignition point of 651℃, slow flame propagation speed, narrow flammability limit, and poor combustion reactivity, resulting in difficulties in ignition, poor combustion stability, and incomplete combustion; (2) NH3 molecules contain nitrogen atoms, and under ideal conditions, the products of complete combustion of ammonia are only nitrogen and water. However, in actual combustion, a large amount of fuel-type NOx is generated. Therefore, the combustion of pulverized coal with ammonia still needs to overcome technical challenges such as flame stability and pollutant control.

[0005] Achieving stable combustion of ammonia fuel while avoiding the generation of large amounts of pollutants is a critical technical problem that urgently needs to be solved in the mixed ammonia combustion process of coal-fired boilers. Summary of the Invention

[0006] The first objective of this invention is to provide a horizontal ammonia-coal burner to achieve stable combustion of ammonia fuel and avoid generating a large amount of pollutants.

[0007] A second objective of this invention is to provide a combustion system including the aforementioned horizontal ammonia-coal burner and a tangentially rounded boiler.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] In a first aspect of this application, a horizontal ammonia-coal burner is provided, wherein one end of the horizontal ammonia-coal burner extending into the furnace is provided with a concentrated and diluted pulverized coal nozzle, a main ammonia fuel nozzle, and a peripheral ammonia fuel nozzle. The concentrated and diluted pulverized coal nozzle and the main ammonia fuel nozzle are arranged sequentially adjacent to each other in the horizontal direction. Except for the side of the concentrated and diluted pulverized coal nozzle adjacent to the main ammonia fuel nozzle, the other sides of the concentrated and diluted pulverized coal nozzle are surrounded by the peripheral ammonia fuel nozzle. A peripheral nozzle adjustment device for adjusting the flow cross-sectional area of ​​the peripheral ammonia fuel nozzle is provided inside the peripheral ammonia fuel nozzle.

[0010] In one possible implementation, the horizontal ammonia-coal burner is further provided with an ammonia fuel concentrated / dilute pulverized coal nozzle at one end extending into the furnace. The ammonia fuel concentrated / dilute pulverized coal nozzle is located between the concentrated phase nozzle and the dilute phase nozzle. A pulverized coal nozzle adjustment device for adjusting the flow cross-sectional area of ​​the ammonia fuel concentrated / dilute pulverized coal nozzle is provided inside the ammonia fuel concentrated / dilute pulverized coal nozzle.

[0011] In one possible implementation, the desalted phase nozzle, the ammonia fuel-rich / desalted pulverized coal inter-nozzle nozzle, the rich phase nozzle, and the ammonia fuel main nozzle are arranged sequentially in a horizontal direction.

[0012] In one possible implementation, a turbulence generator is provided between the dense phase nozzle and the main ammonia fuel nozzle, between the dense phase nozzle and the ammonia fuel pulverized coal intermediate nozzle, and between the dense phase nozzle and the ammonia fuel peripheral nozzle; and / or, a turbulence generator is provided between the dilute phase nozzle and the ammonia fuel pulverized coal intermediate nozzle, and between the dilute phase nozzle and the ammonia fuel peripheral nozzle.

[0013] In one possible implementation, the turbulence generator is a corrugated plate or a sawtooth plate.

[0014] In one possible implementation, the main ammonia fuel nozzle, the peripheral ammonia fuel nozzle, and the ammonia fuel concentrated / diluted coal powder nozzle are high-temperature resistant metal nozzles or high-temperature resistant and corrosion-resistant ceramic nozzles.

[0015] In one possible implementation, a first blunt body is provided between the dense phase nozzle and the desiccant nozzle of the concentrated and desalinated pulverized coal nozzle.

[0016] In one possible implementation, a second blunt body is provided inside the ammonia fuel main nozzle.

[0017] In one possible implementation, at least one longitudinal baffle is provided inside the main ammonia fuel nozzle, and the surface of the longitudinal baffle forms a preset guiding angle with the injection direction of the main ammonia fuel nozzle; and / or, at least one transverse baffle is provided inside the main ammonia fuel nozzle, and the surface of the transverse baffle forms a preset guiding angle with the injection direction of the main ammonia fuel nozzle.

[0018] As can be seen from the above technical solutions, the present invention discloses a horizontal ammonia-coal burner. The horizontal ammonia-coal burner is provided with a concentrated and diluted pulverized coal nozzle, a main ammonia fuel nozzle, and a peripheral ammonia fuel nozzle at one end that extends into the furnace. The concentrated and diluted pulverized coal nozzle and the main ammonia fuel nozzle are arranged adjacent to each other in the horizontal direction. Except for the side of the concentrated and diluted pulverized coal nozzle adjacent to the main ammonia fuel nozzle, the other sides are surrounded by the peripheral ammonia fuel nozzle. A peripheral nozzle adjustment device for adjusting the flow cross-sectional area of ​​the peripheral ammonia fuel nozzle is provided in the peripheral ammonia fuel nozzle.

[0019] In application, the peripheral nozzle adjustment device can be controlled according to the coal quality and boiler load to realize the opening and closing of the ammonia fuel peripheral nozzle and the adjustment of the opening degree. When the peripheral nozzle adjustment device closes the ammonia fuel peripheral nozzle, only the ammonia fuel main nozzle injects ammonia fuel jet into the furnace. When the peripheral nozzle adjustment device opens the ammonia fuel peripheral nozzle, the ammonia fuel peripheral nozzle and the ammonia fuel main nozzle form an ammonia fuel perimeter wind around the rich and light pulverized coal nozzle.

[0020] During combustion, the ammonia fuel gas stream is close to the pulverized coal gas stream, creating a fuel-rich, oxygen-deficient region around the ammonia fuel. This enhances the combustion activity of ammonia, and the atmosphere, which deviates from the theoretical air volume required for ammonia combustion, helps suppress NO. x The process generates heat from pulverized coal pyrolysis and utilizes the released active substances CH4 / H2 to promote the ignition and combustion of ammonia fuel, providing favorable conditions for its ignition. Simultaneously, the ammonia fuel gas flow can create a reducing atmosphere around the pulverized coal flow, reducing the NO generated from the pulverized coal. x This allows ammonia fuel and coal fuel to complement each other's advantages.

[0021] It is evident that the aforementioned horizontal ammonia-coal burner can create an environment with advantages such as high fuel concentration, strong reducing atmosphere, and high ignition heat for ammonia fuel combustion. This significantly improves the ignition stability of the ammonia-coal mixture and suppresses NO pollutant. x The generation of nitrogen oxides and the ability to flexibly adjust the opening and closing of the ammonia fuel peripheral nozzles via the peripheral nozzle adjustment device allow for the mixing of ammonia fuel and pulverized coal at different locations. This adapts to different coal qualities and boiler load requirements, creates different ammonia-coal co-combustion atmospheres, adjusts combustion organization, and ultimately achieves high efficiency and low NOx emissions from pulverized coal burning ammonia fuel. x Low-carbon combustion helps to achieve stable operation of ammonia-coal co-combustion under different load conditions.

[0022] In a second aspect of this application, a combustion system is provided for a tangential boiler, comprising:

[0023] The furnace is equipped with the main combustion zone;

[0024] A horizontal ammonia-coal burner, wherein the horizontal ammonia-coal burner is as described in the first aspect and its possible implementations, wherein the concentrated and diluted pulverized coal nozzle, the main ammonia fuel nozzle, and the peripheral ammonia fuel nozzle of the horizontal ammonia-coal burner are connected to the furnace, wherein the main ammonia fuel nozzle is located on the side of the furnace near the fire-facing side or near the side of the furnace near the fire-repellent side of the furnace, and at least one of the horizontal ammonia-coal burners is provided at at least one corner of the main combustion zone.

[0025] In one possible implementation, a plurality of first and secondary air nozzles are arranged at intervals at the four corners of the furnace along the height direction of the main combustion zone, and a horizontal ammonia-coal burner is arranged between two adjacent first and secondary air nozzles.

[0026] In one possible implementation, wall-mounted air nozzles are respectively provided on both sides of the first secondary air nozzle located at the top and the first secondary air nozzle located at the bottom along the horizontal direction.

[0027] In one possible implementation, the main combustion zone is further provided with a first burnout air nozzle above the first secondary air nozzle located at the top, and wall-mounted air nozzles are respectively provided on both sides of the first burnout air nozzle in the horizontal direction.

[0028] In one possible implementation, the main combustion zone is provided with a plurality of primary air nozzles and a plurality of secondary air nozzles along the height direction of the main combustion zone below the first secondary air nozzle located at the bottom. The primary air nozzles and the secondary air nozzles are arranged alternately and at intervals, and the first secondary air nozzle located at the bottom is separated from the adjacent secondary air nozzle by the primary air nozzle.

[0029] In one possible implementation, the injection direction of the main ammonia fuel nozzle of one of the horizontal ammonia-coal burners arranged adjacent to each other at the same corner of the main combustion zone (210) has a preset deflection angle with the injection direction of the concentrated and diluted pulverized coal nozzle of another horizontal ammonia-coal burner.

[0030] In one possible implementation, the preset deflection angle is greater than 0° and less than or equal to ±60°.

[0031] In one possible implementation, the furnace further includes a burnout zone disposed above the main combustion zone, and a plurality of second burnout air nozzles are disposed at the four corners of the furnace in the height direction of the burnout zone.

[0032] In a third aspect of this application, a tangential boiler is provided, comprising a combustion system as described in the second aspect and its possible implementations.

[0033] Since the combustion system and the tangential boiler adopt the horizontal ammonia-coal burner described in the above embodiments, the combustion system and the tangential boiler should have the same technical effects as the horizontal ammonia-coal burner described above, and will not be described again here. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a front view of a horizontal ammonia-coal burner provided in an embodiment of the present invention;

[0036] Figure 2 This is a schematic diagram of the furnace arrangement of a combustion system provided in an embodiment of the present invention;

[0037] Figure 3 for Figure 2 A magnified view of a portion of point A in the middle.

[0038] In the picture:

[0039] 100 is a horizontal ammonia-coal burner; 110 is a concentrated / dilute pulverized coal nozzle; 111 is a dense phase nozzle; 112 is a dilute phase nozzle; 120 is the main ammonia fuel nozzle; 130 is the peripheral ammonia fuel nozzle; 131 is the first peripheral nozzle section; 1311 is the first nozzle adjustment device; 132 is the second peripheral nozzle section; 1321 is the second nozzle adjustment device; 133 is the third peripheral nozzle section; 1331 is the third nozzle adjustment device; 134 is the fourth peripheral nozzle... Mouth section; 1341 is the fourth nozzle adjustment device; 140 is the ammonia fuel concentrated coal powder nozzle; 150 is the turbulence generator; 160 is the first blunt body; 200 is the furnace; 210 is the main combustion zone; 220 is the burnout zone; 230 is the upper zone of the furnace; 300 is the first and second secondary air nozzles; 400 is the first burnout air nozzle; 500 is the primary air nozzle; 600 is the second and second secondary air nozzles; 700 is the wall-mounted air nozzle; 800 is the second burnout air nozzle. Detailed Implementation

[0040] One of the core aspects of this invention is to provide a horizontal ammonia-coal burner, the structural design of which enables stable combustion of ammonia fuel and avoids the generation of large amounts of pollutants.

[0041] Another core aspect of this invention is to provide a combustion system including the aforementioned horizontal ammonia-coal burner and a tangentially rounded boiler.

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] This application provides a horizontal ammonia-coal burner 100. Please refer to [link / reference]. Figure 1 The horizontal ammonia-coal burner 100 has a concentrated / diluted pulverized coal nozzle 110, a main ammonia fuel nozzle 120, and peripheral ammonia fuel nozzles 130 at one end extending into the furnace 200. The concentrated / diluted pulverized coal nozzle 110 separates the primary air and pulverized coal mixture into two streams, concentrated and dilute, which are then injected into the furnace 200 respectively. The concentrated phase nozzle 111 and the dilute phase nozzle 112 of the concentrated / diluted pulverized coal nozzle 110 can be arranged vertically or horizontally. If the concentrated phase nozzle 111 and the dilute phase nozzle 112 are arranged horizontally, the main ammonia fuel nozzle 120 is located on the side of the concentrated phase nozzle 111 away from the dilute phase nozzle 112, to ensure that the ammonia fuel is in a fuel-rich and oxygen-deficient state. Figure 1 In the embodiment shown, the dense phase nozzle 111 and the dilute phase nozzle 112 are arranged horizontally in the left and right directions.

[0044] The concentrated and diluted pulverized coal nozzle 110 separates the pulverized coal gas flow into a concentrated phase and a diluted phase, allowing the concentrated phase of pulverized coal to burn in a fuel-rich, low-oxygen environment, thus suppressing NO. x The formation of light-phase pulverized coal ensures complete combustion of the fuel by burning it in a relatively lean fuel environment.

[0045] The concentrated-lean separation technology enables a significant increase in the pulverized coal concentration in the dense-phase jet while keeping the total primary air volume constant. Its goal is to create a "three-high zone" near the concentrated-lean pulverized coal nozzle 110—local high temperature, high pulverized coal concentration, and appropriate oxygen concentration. Furthermore, this technology enhances the radiative heat absorption of the furnace flame and can suppress NO₂. x The formation of (under a reducing atmosphere (ammonia)).

[0046] The separation of rich and poor pulverized coal at the nozzle 110 can be achieved in various ways. Currently, the most commonly used structures are centrifugal separation, louvered separation, and baffle-type separation. The centrifugal separation structure utilizes the centrifugal force generated by the mixed airflow of pulverized coal and primary air passing through an arc-shaped flow channel to achieve separation. The louvered separation structure uses multiple progressively arranged louvered baffles to guide the pulverized coal flow, thus achieving separation. The baffle-type separation structure uses one or more baffles installed within the horizontal ammonia-coal burner 100 to guide the mixed airflow of pulverized coal and primary air, achieving separation. In this embodiment, the horizontal ammonia-coal burner 100 can employ one of the above three separation structures for rich and poor separation.

[0047] The ammonia fuel main nozzle 120 can be a pure ammonia gas nozzle, or the ammonia fuel main nozzle 120 can be a double-layer structure with an ammonia gas nozzle in the middle and an air nozzle on the outer periphery of the ammonia gas nozzle, or the ammonia fuel main nozzle 120 can be a premixed ammonia and air nozzle.

[0048] The concentrated and diluted pulverized coal nozzle 110 and the ammonia fuel main nozzle 120 are arranged adjacent to each other in the horizontal direction, that is, the ammonia fuel main nozzle 120 and the concentrated and diluted pulverized coal nozzle 110 are located on the same horizontal plane. Except for the side adjacent to the ammonia fuel main nozzle 120, the other sides of the concentrated and diluted pulverized coal nozzle 110 are surrounded by ammonia fuel peripheral nozzles 130. A peripheral nozzle adjustment device for adjusting the flow cross-sectional area of ​​the ammonia fuel peripheral nozzle 130 is provided inside the ammonia fuel peripheral nozzle 130. The peripheral nozzle adjustment device can control the opening and closing of the ammonia fuel peripheral nozzle 130 and adjust the opening degree.

[0049] In application, the main ammonia fuel nozzle 120 is positioned on the fire-facing side of the furnace 200 near the concentrated / dilute pulverized coal nozzle 110. For a tangential furnace boiler, the fire-facing side of the furnace 200 is determined by the rotation direction of the tangential circle of the combustion airflow within the furnace 200. The side with the larger angle between the airflow and the four furnace walls is the fire-facing side, and the side with the smaller angle is the fire-repellent side. The high-temperature flame on the fire-facing side of the furnace 200 provides additional ignition energy for the ammonia fuel, enabling the ammonia-coal mixture to ignite and burn quickly and stably. This improved ignition stability helps achieve stable operation of the ammonia-coal mixture under different load conditions.

[0050] Because of the peripheral nozzle adjustment device, the peripheral nozzle adjustment device can be controlled according to the coal quality and boiler load to realize the opening and closing of the ammonia fuel peripheral nozzle 130 and the opening degree adjustment, thereby controlling the injection position and injection amount of ammonia fuel. When the peripheral nozzle adjustment device closes the ammonia fuel peripheral nozzle 130, only the ammonia fuel main nozzle 120 injects ammonia fuel jet into the furnace 200. When the peripheral nozzle adjustment device opens the ammonia fuel peripheral nozzle 130, the ammonia fuel peripheral nozzle 130 and the ammonia fuel main nozzle 120 form an ammonia fuel perimeter wind around the rich and light pulverized coal nozzle 110.

[0051] During combustion, the ammonia fuel gas stream is close to the pulverized coal gas stream, creating a fuel-rich, oxygen-deficient region around the ammonia fuel. This enhances the combustion activity of ammonia, and the atmosphere, which deviates from the theoretical air volume required for ammonia combustion, helps suppress NO. x The process generates heat from pulverized coal pyrolysis and utilizes the released active substances CH4 / H2 to promote the ignition and combustion of ammonia fuel, providing favorable conditions for its ignition. Simultaneously, the ammonia fuel gas flow can create a reducing atmosphere around the pulverized coal flow, reducing the NO generated from the pulverized coal. x This allows ammonia fuel and coal fuel to complement each other's advantages.

[0052] The ammonia fuel jets ejected from the main ammonia fuel nozzle 120 and the peripheral ammonia fuel nozzles 130 promote combustion on the concentrated pulverized coal side, increasing the combustion chemical reaction rate and shortening the ignition time and distance. This facilitates complete combustion of the pulverized coal and helps reduce thermal NOx. x generate.

[0053] It is evident that the aforementioned horizontal ammonia-coal burner 100 can provide an environment with advantages such as high fuel concentration, strong reducing atmosphere, and high ignition heat for ammonia fuel combustion. This significantly improves the ignition stability of the ammonia-coal mixture and suppresses NO pollutant. x The ammonia fuel peripheral nozzle 130 can be flexibly adjusted via the peripheral nozzle adjustment device to achieve the purpose of mixing ammonia fuel and pulverized coal at different locations. This adapts to different coal qualities and boiler load requirements, creates different ammonia-coal co-combustion atmospheres, adjusts combustion organization, and ultimately achieves high efficiency and low NOx emissions from pulverized coal burning ammonia fuel. x Low-carbon combustion helps to achieve stable operation of ammonia-coal co-combustion under different load conditions.

[0054] For further optimization of the above technical solution, please refer to [link / reference]. Figure 1In one embodiment of this application, the horizontal ammonia-coal burner 100 is further provided with an ammonia fuel concentrated / dilute pulverized coal nozzle 140 at one end that extends into the furnace 200. The ammonia fuel concentrated / dilute pulverized coal nozzle 140 is located between the concentrated phase nozzle 111 and the dilute phase nozzle 112 of the concentrated / dilute pulverized coal nozzle 110. A pulverized coal nozzle regulating device is provided inside the ammonia fuel concentrated / dilute pulverized coal nozzle 140 for adjusting the flow cross-sectional area of ​​the ammonia fuel concentrated / dilute pulverized coal nozzle 140. That is, the pulverized coal nozzle regulating device is used to control the opening and closing of the ammonia fuel concentrated / dilute pulverized coal nozzle 140 and the opening degree adjustment. When the pulverized coal nozzle regulating device opens the ammonia fuel concentrated / dilute pulverized coal nozzle 140, the ammonia fuel jet is injected into the furnace 200 from between the concentrated phase nozzle 111 and the dilute phase nozzle 112.

[0055] It should be noted that the coal powder room nozzle adjustment device and the peripheral nozzle adjustment device can be controlled independently to achieve independent control of the ammonia fuel concentrated and diluted coal powder room nozzle 140 and the ammonia fuel peripheral nozzle 130.

[0056] Please see Figure 1 The ammonia fuel peripheral nozzle 130 is composed of multiple parts, including a first peripheral nozzle section 131 disposed around the desalted phase nozzle 112, a second peripheral nozzle section 132 disposed around the ammonia fuel concentrated and desalted coal powder inter-nozzle nozzle 140, a third peripheral nozzle section 133 disposed around the concentrated phase nozzle 111, and a fourth peripheral nozzle section 134 disposed around the ammonia fuel main nozzle 120. Correspondingly, the peripheral nozzle regulating device includes a first nozzle regulating device 1311 for controlling the opening and closing and opening degree of the first peripheral nozzle section 131, a second nozzle regulating device 1321 for controlling the opening and closing and opening degree of the second peripheral nozzle section 132, a third nozzle regulating device 1331 for controlling the opening and closing and opening degree of the third peripheral nozzle section 133, and a fourth nozzle regulating device 1341 for controlling the opening and closing and opening degree of the fourth peripheral nozzle section 134.

[0057] Through the above structural design, ammonia fuel can be injected into the furnace 200 from the dense phase nozzle 111 side of the horizontal ammonia-coal burner 100, or ammonia fuel can be injected into the furnace 200 as the periphery air of the mixture of pulverized coal and primary air in the horizontal ammonia-coal burner 100, or ammonia fuel can be introduced from the middle position between the dense phase nozzle 111 and the light phase nozzle 112. By controlling the opening and closing and the opening degree of the nozzle adjustment device in each ammonia fuel nozzle, the purpose of mixing ammonia and pulverized coal at different positions can be achieved, thereby adapting to different coal qualities and boiler load requirements.

[0058] like Figure 1As shown, in one embodiment of this application, the dilute phase nozzle 112, the ammonia fuel-rich / dilute pulverized coal inter-nozzle nozzle 140, the dense phase nozzle 111, and the ammonia fuel main nozzle 120 are arranged sequentially in a horizontal direction, that is, the ammonia fuel main nozzle 120 is located on the side of the dense phase nozzle 111 away from the dilute phase nozzle 112. When the ammonia fuel peripheral nozzle 130 and the ammonia fuel-rich / dilute pulverized coal inter-nozzle nozzle 140 are closed, the ammonia fuel main nozzle 120 injects ammonia fuel from the dense phase nozzle 111 side close to the dense phase pulverized coal into the furnace 200.

[0059] Please see Figure 1 A turbulence generator 150 is installed between the dense phase nozzle 111 and the main ammonia fuel nozzle 120, between the dense phase nozzle 111 and the ammonia fuel pulverized coal intermediate nozzle 140, and between the dense phase nozzle 111 and the ammonia fuel peripheral nozzle 130. Alternatively, a turbulence generator 150 is installed between the light phase nozzle 112 and the ammonia fuel pulverized coal intermediate nozzle 140, and between the light phase nozzle 112 and the ammonia fuel peripheral nozzle 130. This creates an ammonia-coal turbulence vortex between the pulverized coal intermediate nozzle 110 and the surrounding ammonia fuel nozzles, promoting efficient mixing of ammonia gas and pulverized coal particles, enhancing the mass transfer efficiency between the gas and solid phases, promoting fuel mixing, and strengthening the promoting effect of ammonia-coal coupled combustion.

[0060] The turbulence generator 150 is a corrugated plate or a sawtooth plate, that is, the turbulence generator 150 has crests and troughs. One of the crests and troughs bulges towards the ammonia fuel nozzles around the dense phase nozzle 111 or the light phase nozzle 112, and the other of the crests and troughs bulges towards the dense phase nozzle 111 or the light phase nozzle 112.

[0061] The aforementioned turbulence generator 150 can be used to construct a zoned synergistic reaction system by controlling the nozzle of the horizontal ammonia-coal burner 100. Specifically, a pulverized coal enrichment zone is formed near the concentrated and diluted pulverized coal nozzle 110. This pulverized coal enrichment zone serves as the initial jet region for solid fuel, primarily responsible for the stable transport and preheating of pulverized coal particles. An ammonia-dominant zone is formed near each ammonia fuel nozzle. This ammonia-dominant zone serves as an independent transport channel for gaseous fuel. By controlling the jet velocity and diffusion angle, the uniform distribution of ammonia in the main reaction zone is ensured.

[0062] A turbulence-enhanced reduction zone for ammonia-coal is formed between the pulverized coal enrichment zone and the ammonia-dominant zone via a turbulence generator 150. This zone, utilizing the turbulent vortices created by the generator 150, promotes efficient mixing of ammonia and pulverized coal particles, enhances the mass transfer efficiency between the gas and solid phases, improves fuel mixing, and strengthens the coupling combustion effect of ammonia and coal. Simultaneously, some of the ammonia mixed in can contribute to the NO content in the combustion products of adjacent pulverized coal. x Reducing agents to control NO x Emissions.

[0063] The aforementioned zoned synergistic reaction system design, through the synergistic regulation of fluid dynamics and chemical reaction kinetics, can effectively improve the combustion reaction rate and control NO. x generate.

[0064] To improve the durability of each ammonia fuel nozzle and ensure stable boiler operation, the main ammonia fuel nozzle 120, the peripheral ammonia fuel nozzle 130, and the ammonia fuel concentrated / dilute pulverized coal nozzle 140 should be made of high-temperature and corrosion-resistant materials. For example, the main ammonia fuel nozzle 120, the peripheral ammonia fuel nozzle 130, and the ammonia fuel concentrated / dilute pulverized coal nozzle 140 can be high-temperature resistant metal nozzles. The materials used for high-temperature resistant metal nozzles can be nickel-based alloys or other metal materials with a temperature resistance of over 1000℃. Alternatively, the main ammonia fuel nozzle 120, the peripheral ammonia fuel nozzle 130, and the ammonia fuel concentrated / dilute pulverized coal nozzle 140 can be high-temperature resistant and corrosion-resistant ceramic nozzles. The materials used for high-temperature resistant and corrosion-resistant ceramic nozzles can be silicon carbide, zirconium oxide, etc.

[0065] Please see Figure 1 In one embodiment of this application, a first blunt body 160 is provided between the dense phase nozzle 111 and the light phase nozzle 112 of the dense-light coal powder nozzle 110. The blunt body is a non-streamlined object, usually made of metal material. It can cleverly utilize the backflow effect generated by the blunt body wake region through its shape design to entrain high-temperature flue gas, which not only helps the rapid ignition of ammonia coal fuel, but also ensures the stable combustion of the flame.

[0066] Preferably, in one embodiment of this application, a second blunt body is provided inside the ammonia fuel main nozzle 120. Alternatively, at least one longitudinal baffle is provided inside the ammonia fuel main nozzle 120, with the surface of the longitudinal baffle forming a preset guiding angle with the injection direction of the ammonia fuel main nozzle 120, and / or, at least one transverse baffle is provided inside the ammonia fuel main nozzle 120, with the surface of the transverse baffle forming a preset guiding angle with the injection direction of the ammonia fuel main nozzle 120, thereby guiding the ammonia fuel jet so that it can better mix with the flue gas.

[0067] It should be noted that, if conditions permit, blunt body or baffle mechanism may also be installed at the ammonia fuel peripheral nozzle 130 and / or the ammonia fuel concentrated coal powder nozzle 140.

[0068] This application also provides a combustion system for a tangential boiler; please refer to [link to relevant documentation]. Figure 2 and Figure 3 The combustion system includes a furnace 200 and a horizontal ammonia-coal burner 100.

[0069] The furnace 200 is equipped with a main combustion zone 210, which is located in the burner area. Its function is to ignite pulverized coal and ammonia fuel, release volatiles, and burn them. The main combustion zone 210 is the main fuel heat release zone, where about 80% of the total fuel heat is released.

[0070] The horizontal ammonia-coal burner 100 is as described in the above embodiment. The rich and light pulverized coal nozzle 110, the main ammonia fuel nozzle 120, the peripheral ammonia fuel nozzle 130, and the ammonia fuel rich and light pulverized coal nozzle 140 of the horizontal ammonia-coal burner 100 are connected to the furnace 200. At least one horizontal ammonia-coal burner 100 is provided at at least one corner of the main combustion zone 210. The horizontal ammonia-coal burner 100 is used to supply the furnace 200 with a mixture of primary air and pulverized coal and ammonia fuel. At least one horizontal ammonia-coal burner 100 is provided at at least one corner of the main combustion zone 210. That is, one or more horizontal ammonia-coal burners 100 can be provided at one corner of the main combustion zone 210, arranged sequentially along the height direction of the main combustion zone 210. If horizontal ammonia-coal burners 100 are provided at multiple corners of the main combustion zone 210, the horizontal ammonia-coal burners 100 at each corner can be located at the same height or staggered in the height direction of the main combustion zone 210.

[0071] In application, by rationally designing the nozzle angles and positions of the horizontal ammonia-coal burners 100 at the four corners, the ammonia-coal mixed jet injected by the horizontal ammonia-coal burners 100 forms a tangential combustion within the furnace 200. Based on the boiler load and the ammonia-coal blending ratio, the delivery rates of pulverized coal and ammonia are adjusted to ensure that the ammonia-coal blending ratio meets combustion requirements. By adjusting the volume and velocity of the primary and secondary air, the airflow velocity and oxygen content at the burner outlet are controlled, optimizing the combustion environment and further improving combustion stability and efficiency.

[0072] During boiler operation, a high-temperature flame exists in the upper corner of the fire-facing region of the furnace 200. The main ammonia fuel injector 120 is located near this region, allowing it to fully utilize the energy of the high-temperature flame to provide ignition conditions for the ammonia fuel. Simultaneously, the main ammonia fuel injector 120 is close to the pulverized coal flow. The dense phase injector 111 of the rich-lean pulverized coal injector 110 is horizontally adjacent to the main ammonia fuel injector 120. Since the initial combustion of ammonia-coal is in a fuel-rich, oxygen-deficient zone, this region deviates from the theoretical air volume required for ammonia combustion, which is unfavorable for NO₂ production. x Furthermore, during the pyrolysis process, pulverized coal releases active substances such as CH4 and H2, which can promote the ignition of ammonia fuel.

[0073] By controlling the opening and closing of the ammonia fuel peripheral nozzle 130 and the ammonia fuel concentrated coal powder nozzle 140, the injection position and injection amount of ammonia fuel can be adjusted to achieve the purpose of mixing ammonia fuel and coal powder at different positions, adapting to different coal qualities and boiler load requirements.

[0074] Overall, the ammonia combustion environment of the above-mentioned combustion system has advantages such as high fuel concentration, strong reducing atmosphere, and high ignition heat, which can significantly improve the ignition stability of the ammonia-coal mixture and suppress NO. x The generation of ammonia fuel jets enables tangential combustion of ammonia fuel in a four-corner tangential boiler, achieving efficient and low-carbon combustion of pulverized coal mixed with ammonia fuel.

[0075] The tangential combustion method can enhance the disturbance and mixing of airflow in the furnace, improve combustion efficiency, and ensure that ammonia fuel is fully burned, thereby achieving efficient and low-carbon combustion of pulverized coal and ammonia fuel in a four-corner tangential boiler.

[0076] The aforementioned combustion system requires no oxygen enrichment or pure oxygen for combustion, thus eliminating safety hazards and effectively ensuring the safe and stable operation of the combustion equipment. Within the ammonia blending ratio range of 0-60% (calorific value ratio), only the number or opening of each ammonia fuel nozzle needs to be adjusted to meet the applicability of high-proportion ammonia blending conditions. It maintains the boiler's input calorific value at the corresponding load, thereby achieving a proportional reduction in carbon emissions. This invention addresses the high carbon emission problem of tangentially shaped coal-fired boilers at the fuel utilization end. For ammonia blending retrofits of coal-fired units or the construction of new ammonia-blended coal-fired units, the ammonia combustion equipment and systems involved are simple, resulting in low retrofitting and construction costs, low operating costs, and low operational complexity. Therefore, this invention can be widely applied to tangentially shaped pulverized coal boilers, playing a significant role in the low-carbon transformation of the energy structure of coal-fired power plants.

[0077] It should be noted that the excess air coefficient in the main combustion zone 210 is 0.6~0.98, achieving staged air combustion for ammonia-coal in the furnace 200, which is beneficial for suppressing NO. x The generation of NO is further enhanced by the adoption of a horizontal ammonia-coal burner (100°C). This results in a high concentration of pulverized coal and ammonia fuel, creating a reducing atmosphere that is more conducive to reducing NO. x In oxygen-deficient regions, due to the reducing properties of ammonia, NH3 can act as both a fuel and a catalyst for the combustion of NO. x The reducing agent can further inhibit NO. x The generation of .

[0078] Preferably, ammonia fuel can be injected into a specific flame temperature range (850℃~1150℃) by adjusting the appropriate jet angle of each ammonia fuel nozzle, thereby reducing the NO generated by the pulverized coal. x This enables efficient and low-carbon combustion of pulverized coal mixed with ammonia fuel in a four-corner tangential boiler.

[0079] Of course, those skilled in the art will understand that, in addition to supplying a mixture of primary air and pulverized coal, as well as ammonia fuel, to the furnace 200 via the horizontal ammonia-coal burner 100, secondary air, burnout air, and wall-mounted air should also be arranged as needed. Therefore, if Figure 3As shown, multiple primary and secondary air nozzles 300 are sequentially and spaced apart at the four corners of the furnace 200 along the height direction of the main combustion zone 210. A horizontal ammonia-coal burner 100 is arranged between two adjacent primary and secondary air nozzles 300. One or more horizontal ammonia-coal burners 100 can be arranged between two primary and secondary air nozzles 300. The number of primary and secondary air nozzles 300 can be 2, 3, 4, 5, etc., depending on the size of the main combustion zone 210, and is not limited here.

[0080] exist Figure 3 In the embodiment shown, three first and secondary air nozzles 300 are arranged sequentially in the height direction of the main combustion zone 210, and two horizontal ammonia-coal burners 100 are arranged accordingly. The two horizontal ammonia-coal burners 100 are respectively arranged between two adjacent first and secondary air nozzles 300, that is, there is one and only one horizontal ammonia-coal burner 100 between two adjacent first and secondary air nozzles 300.

[0081] Please see Figure 3 In one embodiment of this application, wall-mounted air nozzles 700 are respectively provided on both sides of the uppermost and lowermost first and secondary air nozzles 300. The burnout air injected by the wall-mounted air nozzles 700 can run along the wall of the furnace 200, forming wall-mounted air, thereby forming an oxide protective layer on the wall surface and avoiding high-temperature corrosion of the furnace 200 wall caused by the reducing environment. Moreover, the burnout air running along the wall will not disturb the airflow inside the furnace 200 and will not affect the daily operation of the boiler.

[0082] Please continue reading. Figure 3 In one embodiment of this application, the main combustion zone 210 is further provided with a first burnout air nozzle 400 above the uppermost first secondary air nozzle 300, and wall-mounted air nozzles 700 are respectively provided on both sides of the first burnout air nozzle 400. The first burnout air nozzle 400 is used to provide the burnout air required for the combustion of ammonia-coal fuel.

[0083] Furthermore, such as Figure 3 As shown, the main combustion zone 210 has multiple primary air nozzles 500 and multiple secondary air nozzles 600 arranged along the height direction of the main combustion zone 210 below the lowest primary and secondary air nozzles 300. The primary air nozzles 500 and secondary air nozzles 600 are arranged alternately, and the lowest primary and secondary air nozzles 300 and the adjacent secondary air nozzles 600 are separated by primary air nozzles 500. By adjusting the air volume and air velocity of the primary and secondary air, the airflow velocity and oxygen content of the nozzle of the horizontal ammonia coal burner 100 are controlled, the combustion environment is optimized, and the combustion stability and efficiency are further improved.

[0084] To further optimize the above technical solution, the injection direction of the main ammonia fuel nozzle 120 of one horizontal ammonia-coal burner 100 arranged adjacent to each other at the same corner of the main combustion zone 210 has a preset deflection angle with the injection direction of the concentrated and diluted pulverized coal nozzle 110 of another horizontal ammonia-coal burner 100. Preferably, the preset deflection angle is greater than 0° and less than or equal to ±60°, which can realize the tangential or anti-tangential of the ammonia fuel jet to the combustion airflow in the furnace 200. The above-mentioned adjacent arrangement at the same corner includes two cases: that is, the two horizontal ammonia-coal burners 100 are directly adjacent and there are no other nozzles between them; or the two horizontal ammonia-coal burners 100 are indirectly adjacent, that is, there are one or more other nozzles (such as the first and secondary air nozzles 300) between them in addition to the horizontal ammonia-coal burners 100.

[0085] Of course, those skilled in the art will know that, in addition to the main combustion zone 210, the furnace 200 also includes a burnout zone 220 and an upper furnace zone 230 arranged sequentially above the main combustion zone 210. Multiple second burnout air nozzles 800 are arranged at the four corners of the furnace 200 in the height direction of the burnout zone 220 to provide the air required for fuel combustion.

[0086] This application also provides a tangentially rounded boiler, which includes the combustion system described in the above embodiments. Since the tangentially rounded boiler uses the combustion system described in the above embodiments, the technical effects of the tangentially rounded boiler can be found in the above embodiments.

[0087] As indicated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "a," and / or "the" are not specifically singular and may include the plural. Generally, the terms "comprising" and "including" only indicate the inclusion of expressly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements. An element defined by the phrase "comprising an..." does not exclude the presence of other identical elements in the process, method, product, or apparatus that includes the element.

[0088] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0089] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0090] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A horizontal ammonia-coal burner, characterized in that, The horizontal ammonia-coal burner (100) is provided with a concentrated pulverized coal nozzle (110), an ammonia fuel main nozzle (120), and an ammonia fuel peripheral nozzle (130) at one end that extends into the furnace (200). The concentrated pulverized coal nozzle (110) and the ammonia fuel main nozzle (120) are arranged adjacent to each other in the horizontal direction. Except for the side adjacent to the ammonia fuel main nozzle (120), the other side of the concentrated pulverized coal nozzle (110) is surrounded by the ammonia fuel peripheral nozzle (130). The ammonia fuel peripheral nozzle (130) is provided with a peripheral nozzle adjustment device for adjusting the flow cross-sectional area of ​​the ammonia fuel peripheral nozzle (130).

2. The horizontal ammonia-coal burner according to claim 1, characterized in that, The horizontal ammonia-coal burner (100) is provided with an ammonia fuel concentrated and dilute pulverized coal nozzle (140) at one end that extends into the furnace (200). The ammonia fuel concentrated and dilute pulverized coal nozzle (140) is located between the concentrated phase nozzle (111) and the dilute phase nozzle (112) of the concentrated and dilute pulverized coal nozzle (110). The ammonia fuel concentrated and dilute pulverized coal nozzle (140) is provided with a pulverized coal nozzle adjustment device for adjusting the flow cross-sectional area of ​​the ammonia fuel concentrated and dilute pulverized coal nozzle (140).

3. The horizontal ammonia-coal burner according to claim 2, characterized in that, The light phase nozzle (112), the ammonia fuel pulverized coal intermediate nozzle (140), the dense phase nozzle (111), and the ammonia fuel main nozzle (120) are arranged sequentially in the horizontal direction.

4. The horizontal ammonia-coal burner according to claim 3, characterized in that, A turbulence generator (150) is provided between the dense phase nozzle (111) and the main ammonia fuel nozzle (120), between the dense phase nozzle (111) and the ammonia fuel pulverized coal intermediate nozzle (140), and between the dense phase nozzle (111) and the ammonia fuel peripheral nozzle (130), and / or, a turbulence generator (150) is provided between the dilute phase nozzle (112) and the ammonia fuel pulverized coal intermediate nozzle (140), and between the dilute phase nozzle (112) and the ammonia fuel peripheral nozzle (130).

5. The horizontal ammonia-coal burner according to claim 4, characterized in that, The turbulence generator (150) is a corrugated plate or a sawtooth plate.

6. The horizontal ammonia-coal burner according to any one of claims 2-5, characterized in that, The ammonia fuel main nozzle (120), the ammonia fuel peripheral nozzle (130), and the ammonia fuel concentrated / dilute coal powder nozzle (140) are high-temperature resistant metal nozzles or high-temperature resistant and corrosion-resistant ceramic nozzles.

7. The horizontal ammonia-coal burner according to claims 1-5, characterized in that, A first blunt body (160) is provided between the dense phase nozzle (111) and the dilute phase nozzle (112) of the dense and dilute pulverized coal nozzle (110).

8. The horizontal ammonia-coal burner according to any one of claims 1-5, characterized in that, A second blunt body is provided inside the main ammonia fuel nozzle (120).

9. The horizontal ammonia-coal burner according to any one of claims 1-5, characterized in that, At least one longitudinal baffle is provided inside the ammonia fuel main nozzle (120), and the surface of the longitudinal baffle forms a preset guide angle with the injection direction of the ammonia fuel main nozzle (120), and / or, at least one transverse baffle is provided inside the ammonia fuel main nozzle (120), and the surface of the transverse baffle forms a preset guide angle with the injection direction of the ammonia fuel main nozzle (120).

10. A combustion system for a tangentially circular boiler, characterized in that, include: Furnace (200), with main combustion zone (210); A horizontal ammonia-coal burner (100) is a horizontal ammonia-coal burner (100) as described in any one of claims 1 to 9. The pulverized coal nozzle (110), the main ammonia fuel nozzle (120), and the peripheral ammonia fuel nozzle (130) of the horizontal ammonia-coal burner (100) are connected to the furnace (200). The main ammonia fuel nozzle (120) is located on the side of the furnace (200) facing the fire or on the side of the furnace (200) facing away from the fire, and at least one of the horizontal ammonia-coal burners (100) is provided at at least one corner of the main combustion zone (210).

11. The combustion system according to claim 10, characterized in that, The four corners of the furnace (200) are provided with a plurality of first and secondary air nozzles (300) at intervals in the height direction of the main combustion zone (210), and the horizontal ammonia-coal burner (100) is provided between two adjacent first and secondary air nozzles (300).

12. The combustion system according to claim 11, characterized in that, The first secondary air nozzle (300) located at the top and the first secondary air nozzle (300) located at the bottom are respectively provided with wall-mounted air nozzles (700) on both sides in the horizontal direction.

13. The combustion system according to claim 11, characterized in that, The main combustion zone (210) is further provided with a first burnout air nozzle (400) above the first secondary air nozzle (300) located at the top. The first burnout air nozzle (400) is provided with wall-mounted air nozzles (700) on both sides along the horizontal direction.

14. The combustion system according to claim 11, characterized in that, The main combustion zone (210) has a plurality of primary air nozzles (500) and a plurality of secondary air nozzles (600) arranged along the height direction of the main combustion zone (210) below the first secondary air nozzle (300) located at the bottom. Each primary air nozzle (500) and each secondary air nozzle (600) are arranged alternately and at intervals, and the first secondary air nozzle (300) located at the bottom and the adjacent secondary air nozzle (600) are separated by the primary air nozzle (500).

15. The combustion system according to any one of claims 10-14, characterized in that, The injection direction of the main ammonia fuel nozzle (120) of one of the horizontal ammonia-coal burners (100) arranged adjacent to each other at the same corner of the main combustion zone (210) has a preset deflection angle with the injection direction of the concentrated and diluted pulverized coal nozzle (110) of another horizontal ammonia-coal burner (100).

16. The combustion system according to claim 15, characterized in that, The preset deflection angle is greater than 0° and less than or equal to ±60°.

17. The combustion system according to any one of claims 10-14, characterized in that, The furnace (200) also includes a burnout zone (220) located above the main combustion zone (210), and a plurality of second burnout air nozzles (800) are provided at the four corners of the furnace (200) in the height direction of the burnout zone (220).

18. A four-corner tangent-circle boiler, characterized in that, Including the combustion system as described in any one of claims 10-17.

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