阅读说明：本技术 一种用于旋流燃烧器掺烧氨气的燃烧系统 (Combustion system for blending ammonia gas in cyclone burner ) 是由 李月华 韩志江 闫凯 王迪 于 2021-07-29 设计创作，主要内容包括：本发明提供了一种用于旋流燃烧器掺烧氨气的燃烧系统,涉及燃料燃烧技术领域,包括旋流燃烧器、第一燃烧室、第二燃烧室和多个氨喷口,在煤粉或碳氢燃料旋流燃烧器后的第一燃烧室内进行掺烧氨气,在保证燃料总出力不变的情况下,可大幅减少CO-2的生成,降低碳排放；通过在第一燃烧室内敷设耐火材料,减少该区域壁面的吸热量,保证第一燃烧室内处于高温的环境,有利于保证氨气混入后火焰稳定燃烧,同时旋流燃烧器和第二燃烧室的分级配风,使得第一燃烧室氨喷口附近局部区域呈现高温、贫氧的还原性气氛,可以抑制NOx的生成,控制掺氨燃烧后NOx的排放。(The invention provides a combustion system for blending ammonia gas in a cyclone burner, which relates to the technical field of fuel combustion and comprises the cyclone burner, a first combustion chamber, a second combustion chamber and a plurality of ammonia nozzles, wherein the ammonia gas is blended in the first combustion chamber behind the cyclone burner of pulverized coal or hydrocarbon fuel, and CO can be greatly reduced under the condition of ensuring that the total output of the fuel is unchanged 2 The carbon emission is reduced; the refractory material is laid in the first combustion chamber, so that the heat absorption capacity of the wall surface of the area is reduced, the high-temperature environment in the first combustion chamber is ensured, the stable combustion of flame after ammonia gas is mixed is ensured, and meanwhile, the staged air distribution of the cyclone burner and the second combustion chamber ensures that the local area near the ammonia nozzle of the first combustion chamber presents high-temperature oxygen-poor reducing atmosphere, the generation of NOx can be inhibited, and the emission of NOx after ammonia-mixed combustion is controlled.)

1. The utility model provides a combustion system for swirl burner mixes burning ammonia, its characterized in that, includes swirl burner (1), first combustion chamber (2), second combustion chamber (3) and a plurality of ammonia spout (5), swirl burner (1) is buggy or hydrocarbon fuel swirl burner, first combustion chamber (2) with the primary air passageway and the overgrate air access connection of swirl burner (1), second combustion chamber (3) with first combustion chamber (2) are connected, ammonia spout (5) with first combustion chamber (2) are connected.

2. The combustion system for the swirl burner to mix and burn ammonia gas according to claim 1, characterized in that the first combustion chamber (2) and the second combustion chamber (3) are in the shape of hollow cylinder or hollow right quadrangular prism, the second combustion chamber (3) is arranged in a vertical or horizontal manner, and the second combustion chamber (3) is connected with the burnout duct (4).

3. The combustion system for the swirl burner to mix and burn ammonia gas according to claim 2, characterized in that when the second combustion chamber (3) is arranged vertically, the over-fire air in the over-fire air duct (4) is injected into the second combustion chamber (3) horizontally, and when the second combustion chamber (3) is arranged horizontally, the over-fire air in the over-fire air duct (4) is injected into the second combustion chamber (3) vertically.

4. The combustion system for blending ammonia gas with a cyclone burner as defined in claim 1, wherein the ammonia nozzle (5) is connected with an ammonia gas distribution header (6), the ammonia gas distribution header (6) is connected with a gasifier (7), and the gasifier (7) is connected with a liquid ammonia storage device (8).

5. The combustion system for blended combustion of ammonia gas by a cyclone burner as in claim 1, wherein the ammonia nozzles (5) are distributed in stages on the side wall of the first combustion chamber (2) along the axial direction of the first combustion chamber (2), each stage of the ammonia nozzles (5) is distributed along the circumferential direction of the first combustion chamber (2), and each stage of the ammonia nozzles (5) is connected with a control device.

6. The combustion system for the swirl burner to mix and burn ammonia gas according to claim 5, wherein the ammonia nozzles (5) are distributed on the side wall of the first combustion chamber (2) in 3-6 stages along the axial direction of the first combustion chamber (2), and each stage of the ammonia nozzles (5) is distributed with 3-12 ammonia nozzles (5) along the circumferential direction of the first combustion chamber (2).

7. The combustion system for the swirl burner to mix and burn ammonia gas according to claim 1, wherein the heat value of the mixed and burned ammonia gas in the first combustion chamber (2) accounts for 0-50%, a refractory material is laid on the inner wall of the first combustion chamber (2), and a temperature control device for measuring and controlling the temperature of the first combustion chamber (2) is arranged, so that the temperature in the first combustion chamber (2) ranges from 800 ℃ to 1200 ℃, and the excess air coefficient in the first combustion chamber (2) ranges from 0.8-1.05.

Technical Field

The invention belongs to the technical field of fuel combustion, and particularly relates to a combustion system for blending ammonia gas in a cyclone burner.

Background

The energy provided by coal-fired power generation accounts for about 29% of the world's primary energy, and compared with any other power generation mode, CO generated by coal-fired boilers₂The discharge amount is more. In recent years, the global economy 'low-carbon' trend is increasingly strengthened, and main economies in the world are successively added "Paris agreement ", and corresponding carbon emission reduction targets and plans are formulated. Therefore, CO of coal-fired boiler of thermal power plant is reduced₂There is considerable potential for emissions. As the second major economic body in the world, China sets up a carbon emission peak reaching action scheme before 2030 years, strives for reaching a peak value before 2030 years, and realizes carbon neutralization before 2060 years. The utilization of 'zero carbon' fuel instead of traditional fossil fuel is one of the effective carbon emission reduction modes.

The coal or hydrocarbon fuel combustion technology is widely applied, the research on the combustion characteristic and the NOx emission characteristic is tested by long-term engineering practice at home and abroad, and the relevant technology is mature, but the problem of reducing the carbon emission of the coal or hydrocarbon fuel combustion technology needs to be considered when the low-carbon tendency is met. Ammonia gas (NH)₃) Is a good carrier of hydrogen energy compared with hydrogen gas (H)₂) The main advantages of ammonia are high hydrogen content and high volumetric energy density, which are even higher per unit volume than liquid hydrogen. Meanwhile, the fuel is easy to liquefy, convenient to store and transport, high in safety and the like due to the mature production process, is considered to be a more potential clean fuel, and can be effectively used as a carrier of hydrogen and energy. Production of NH in view of renewable energy₃Has limited ability to use NH for a short period₃Completely replaces coal. Therefore, the mixed combustion of ammonia gas and coal or hydrocarbon fuel in the boiler also needs to be studied intensively. NH (NH)₃There are two very significant problems with direct combustion as a fuel: poor combustion characteristics and high NOx emissions.

Therefore, it is important to provide a method for reducing carbon emission by blending ammonia based on the current state of the art of coal or hydrocarbon fuel combustion. Therefore, mature coal or hydrocarbon fuel combustion technology and matched pollutant emission control technology can be utilized, and carbon emission can be effectively reduced under the condition of ensuring output.

Disclosure of Invention

The invention aims to provide a combustion system for blending ammonia gas in a cyclone burner, which aims to solve the problems in the background technology.

In order to solve the technical problem, the invention provides a combustion system for mixing and burning ammonia gas in a cyclone burner, which comprises the cyclone burner, a first combustion chamber, a second combustion chamber and a plurality of ammonia nozzles, wherein the cyclone burner is a pulverized coal or hydrocarbon fuel cyclone burner, the first combustion chamber is connected with a primary air channel and a secondary air channel of the cyclone burner, the second combustion chamber is connected with the first combustion chamber, and the ammonia nozzles are connected with the first combustion chamber.

The structure of the cyclone burner comprises a primary air channel and a secondary air channel, and primary air and secondary air are respectively provided for the first combustion chamber, the primary air and the secondary air can be arranged in a cyclone or direct flow structural form, and for the pulverized coal furnace, the primary air is air for conveying fuel.

Further, the first combustion chamber and the second combustion chamber are in the shape of a hollow cylinder or a hollow right quadrangular prism, the second combustion chamber is arranged in a vertical mode or a horizontal mode, and the second combustion chamber is connected with the burnout air duct.

Further, when the second combustion chamber is arranged vertically, the over-fire air in the over-fire air channel is horizontally sprayed into the second combustion chamber, and when the second combustion chamber is arranged horizontally, the over-fire air in the over-fire air channel is vertically sprayed into the second combustion chamber.

The first combustion chamber and the second combustion chamber are in the shape of a hollow cylinder or a hollow right quadrangular prism, so that the cross section of the first combustion chamber and the second combustion chamber is circular or rectangular;

when the second combustion chamber is arranged in a vertical mode, the round bottom surface or the rectangular bottom surface of the second combustion chamber is in contact with the ground, and the main influence of the vertical arrangement and the horizontal arrangement of the second combustion chamber is the floor area of the equipment and the influence on related accessories and auxiliary equipment.

When the second combustion chamber is vertically or horizontally arranged, almost no influence is caused on the arrangement mode of the first combustion chamber, the main influence is the flue gas flow path of the over-fire air, when the second combustion chamber is horizontally arranged, the over-fire air in the over-fire air channel is sprayed into the second combustion chamber in the vertical direction, and when the second combustion chamber is vertically arranged, the over-fire air in the over-fire air channel is sprayed into the second combustion chamber in the horizontal direction. The fuel can be ensured to burn out by adding the over-fire air.

Further, the ammonia nozzle is connected with an ammonia gas distribution header, the ammonia gas distribution header is connected with a gasifier, and the gasifier is connected with a liquid ammonia storage device.

Further, the ammonia nozzles are distributed on the side wall of the first combustion chamber in a grading manner along the axial direction of the first combustion chamber, the ammonia nozzles of each grade are distributed along the circumferential direction of the first combustion chamber, and the ammonia nozzles of each grade are connected with a control device.

Liquid ammonia by liquid ammonia storage device sends into through the pipeline the vaporizer, liquid ammonia gasification back is sent into the ammonia distribution collection case, then the rethread ammonia distribution collection case spouts the ammonia in sending into each ammonia spout, because each grade ammonia spout all is connected with a controlling means, so can be through control the flow ratio that the ammonia spouts into first combustion chamber along with each grade ammonia spout is controlled to valve aperture among the controlling means.

The ammonia nozzles are distributed on the side wall of the first combustion chamber in a grading manner along the axial direction of the first combustion chamber, that is, the ammonia nozzles are arranged on the side wall from one end of the first combustion chamber to the other end of the first combustion chamber along the central axis of the first combustion chamber, the ammonia nozzles on each layer are distributed along the circumferential direction of the cross section of the first combustion chamber, and the number of the ammonia nozzles is more than one.

Further, the ammonia nozzle is in along the axial direction of first combustion chamber divide 3 ~ 6 grades of distributions on the lateral wall of first combustion chamber, every grade the ammonia nozzle is along the circumference distribution 3 ~ 12 ammonia nozzles of first combustion chamber.

Furthermore, the heat value of the ammonia gas doped in the first combustion chamber accounts for 0-50%, a refractory material is laid on the inner wall of the first combustion chamber, and a temperature control device for measuring and controlling the temperature of the first combustion chamber is arranged, so that the temperature range in the first combustion chamber is 800-1200 ℃, and the excess air coefficient in the first combustion chamber is 0.8-1.05.

The heat value proportion refers to the amount of ammonia when the heat generated by combustion of the blended ammonia accounts for 0-50% of the heat generated by combustion of all fuels.

The purpose of laying refractory materials on the inner wall of the first combustion chamber and arranging the temperature control device is to ensure the rapid ignition and combustion of ammonia gas and avoid the generation of coking and burning loss caused by overhigh temperature in the first combustion chamber.

The cyclone burner is provided with primary air or secondary air carrying pulverized coal or hydrocarbon fuel in a direct flow or cyclone mode, and the primary air or the secondary air is sent into the first combustion chamber in a grading air distribution mode, so that the excess air coefficient in the first combustion chamber is ensured to be 0.8-1.05, the part near the ammonia nozzle of the first combustion chamber is in a fuel-rich environment, namely the part near the ammonia nozzle of the first combustion chamber presents a high-temperature oxygen-poor reducing atmosphere, the generation of NOx can be inhibited, and the emission of NOx after ammonia-doped combustion is controlled.

The fuel combustion needs sufficient oxygen quantity, and the staged air distribution is to send the oxygen quantity into the combustion area in stages, so that the over-high temperature caused by over-concentrated fuel combustion can be avoided, and simultaneously, the oxygen quantity is high, and a large amount of NOx can be generated. After the air distribution in a grading way, the oxygen is insufficient in a combustion area, and the combustion area is in a reducing atmosphere, so that the generation of NOx is favorably inhibited.

The excess air factor is also referred to as "excess air factor" and "excess air factor", and is commonly referred to as "residual air factor". Refers to the ratio of the amount of air actually supplied to the fuel for combustion to the theoretical amount of air. Is an important parameter reflecting the fuel to air ratio.

The first combustion chamber is controlled to be in an oxygen-deficient environment overall, fuel cannot be burnt out, meanwhile, no heating surface is arranged, the second combustion chamber is a main body part of the boiler, the heating surface is arranged to absorb heat released after the fuel is burnt, the unburned fuel in the first combustion chamber enters the second combustion chamber, and meanwhile, oxygen required by the combustion of residual fuel is supplemented through the feeding of over-fire air, so that the effects of burning out and reducing NOx are achieved.

Has the advantages that:

(1) the invention provides a combustion system for blending ammonia gas in a cyclone burner, which comprises the cyclone burner, a first combustion chamber,The second combustion chamber and a plurality of ammonia nozzles are used for blending and combusting ammonia gas in the first combustion chamber behind the pulverized coal or hydrocarbon fuel cyclone burner, so that CO can be greatly reduced under the condition of ensuring that the total output of fuel is unchanged₂The carbon emission is reduced; the refractory material is laid in the first combustion chamber, so that the heat absorption capacity of the wall surface of the area is reduced, the high-temperature environment in the first combustion chamber is ensured, the stable combustion of flame after ammonia gas is mixed is ensured, and meanwhile, the staged air distribution of the cyclone burner and the second combustion chamber ensures that the local area near the ammonia nozzle of the first combustion chamber presents high-temperature oxygen-poor reducing atmosphere, the generation of NOx can be inhibited, and the emission of NOx after ammonia-mixed combustion is controlled.

(2) The invention provides a combustion system for blending combustion of ammonia gas by a cyclone burner, which is characterized in that on the basis of utilizing the existing coal or hydrocarbon fuel cyclone burner technology, a first combustion chamber laid with refractory materials is designed to blend combustion of ammonia fuel, so that the carbon emission of combustion is greatly reduced under the condition of ensuring the output of fuel; the second combustion chamber containing the over-fire air is designed, so that the over-fire effect of the fuel is ensured, and the emission of NOx can be effectively controlled; by designing the two-stage combustion chamber, the ammonia grading nozzle and the grading air distribution mode, the economical efficiency and the environmental protection effect of fuel combustion can be greatly improved.

The conception, the specific structure and the technical effects of the present invention will be further described with reference to the accompanying drawings to fully understand the objects, the features and the effects of the present invention.

Drawings

FIG. 1 is a schematic structural diagram of a horizontal arrangement of a second combustion chamber in a combustion system for blending ammonia gas with a cyclone burner according to the present invention;

FIG. 2 is a schematic structural diagram of a vertical arrangement of a second combustion chamber in the combustion system for blending ammonia gas with a cyclone burner according to the present invention;

FIG. 3 is a schematic view of the circumferential arrangement of the ammonia ports of the present invention when the first combustion chamber is circular in cross section;

FIG. 4 is a schematic view of the circumferential arrangement of the ammonia ports in the case of the first combustion chamber of the present invention having a rectangular cross section;

FIG. 5 is a schematic view of the present invention in which the ammonia nozzles are distributed in 4 stages on the sidewall of the first combustion chamber in the axial direction of the first combustion chamber;

description of the drawings:

1. a cyclone burner; 2. a first combustion chamber; 3. a second combustion chamber; 4. a burnout air duct; 5. an ammonia nozzle; 6. an ammonia gas distribution header; 7. a gasifier; 8. a liquid ammonia storage device.

Detailed Description

The invention will be further illustrated with reference to specific embodiments. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.

In the drawings, structurally identical elements are represented by like reference numerals, and structurally or functionally similar elements are represented by like reference numerals throughout the several views. The size and thickness of each component shown in the drawings are arbitrarily illustrated, and the present invention is not limited to the size and thickness of each component. The thickness of the components may be exaggerated where appropriate in the figures to improve clarity.

Example 1:

as shown in fig. 1 and 3, in a preferred embodiment, a combustion system for mixing ammonia gas with a cyclone burner is provided, which includes a cyclone burner 1, a first combustion chamber 2, a second combustion chamber 3 and a plurality of ammonia nozzles 5, wherein the cyclone burner 1 is a pulverized coal or hydrocarbon fuel cyclone burner, the first combustion chamber 2 is connected with a primary air channel and a secondary air channel of the cyclone burner 1, the second combustion chamber 3 is connected with the first combustion chamber 2, and the ammonia nozzles 5 are connected with the first combustion chamber 2.

The cyclone burner 1 has a structure including a primary air passage and a secondary air passage, and supplies primary air and secondary air to the first combustion chamber 2, respectively, and both the primary air and the secondary air may be arranged in a cyclone or straight flow structure, and for a pulverized coal furnace, the primary air is generally air for transporting fuel.

In this embodiment, the first combustion chamber 2 is a hollow cylinder, the second combustion chamber 3 is arranged horizontally, the second combustion chamber 3 is connected with an over-fire air duct 4, and the over-fire air duct 4 is arranged above the second combustion chamber 3 and vertically injects over-fire air into the second combustion chamber 3. The fuel can be ensured to burn out by adding the over-fire air.

Since the first combustion chamber 2 is shaped as a hollow cylinder, its cross section is circular;

further, the ammonia nozzle 5 is connected with an ammonia gas distribution header 6, the ammonia gas distribution header 6 is connected with a vaporizer 7, and the vaporizer 7 is connected with a liquid ammonia storage device 8.

Further, the ammonia nozzles 5 are distributed on the side wall of the first combustion chamber 2 in stages along the axial direction of the first combustion chamber 2, each stage of the ammonia nozzles 5 is distributed along the circumferential direction of the first combustion chamber 2, and each stage of the ammonia nozzles 5 is connected with a control device.

Liquid ammonia by liquid ammonia storage device 8 sends into through the pipeline vaporizer 7, liquid ammonia gasification back, sends into ammonia distribution collection case 6, then passes through again ammonia distribution collection case 6 sends into ammonia and spouts ammonia and buggy or hydrocarbon fuel mixed combustion in sending into each ammonia spout 5, because each grade ammonia spout 5 all is connected with a controlling means, so can be through control the flow ratio that ammonia spouts into first combustion chamber 2 along with each grade ammonia spout 5 is controlled to valve aperture among the controlling means.

The fact that the ammonia outlet ports 5 are distributed in stages on the side wall of the first combustion chamber 2 along the axial direction of the first combustion chamber 2 means that the ammonia outlet ports 5 are provided in a plurality of stages along the side wall from one end of the first combustion chamber 2 to the other end along the central axis of the first combustion chamber 2, and the ammonia outlet ports 5 of each stage are distributed along the circumferential direction of the cross section of the first combustion chamber 2.

In the embodiment, the axial direction of the first combustion chamber 2 is the left-right direction, the ammonia nozzles 5 are distributed on the outer side of the first combustion chamber 2 in 4 stages along the axial direction, and a control device is arranged on each stage of ammonia nozzle 5, so that the flexible control along the axial direction in stages can be realized; as shown in FIG. 3, each stage of ammonia nozzles are circumferentially distributed with 6 ammonia nozzles

Further, the heat value of the ammonia gas doped in the first combustion chamber 2 accounts for 0-50%, a refractory material is laid on the inner wall of the first combustion chamber 2, a temperature control device used for measuring and controlling the temperature of the first combustion chamber 2 is arranged, and the excess air coefficient in the first combustion chamber 2 is 0.8-1.05.

The heat value proportion refers to the amount of ammonia when the heat generated by combustion of the blended ammonia accounts for 0-50% of the heat generated by combustion of all fuels.

The purpose of laying refractory materials on the inner wall of the first combustion chamber 2 and arranging a temperature control device is to ensure the quick ignition and combustion of ammonia gas and avoid the generation of coking and burning loss caused by overhigh temperature in the first combustion chamber 2.

The cyclone combustor 1 is provided with primary air or secondary air carrying pulverized coal or hydrocarbon fuel in a direct flow or cyclone mode, and meanwhile, the cyclone combustor 1 and the second combustion chamber 3 are subjected to graded air distribution to ensure that the excess air coefficient in the first combustion chamber 2 is 0.8-1.05, so that the part near the ammonia nozzle 5 of the first combustion chamber 2 is in a fuel-rich environment, namely the part near the ammonia nozzle 5 of the first combustion chamber 2 presents a high-temperature oxygen-poor reducing atmosphere, the generation of NOx can be inhibited, and the emission of NOx after ammonia-doped combustion is controlled.

The graded air distribution refers to all air required by fuel combustion, wherein one part of the air is sent into the first combustion chamber through the cyclone burner, and the other part of the air is sent into the second combustion chamber through over-fired air, namely the air distribution mode that the air enters in two stages integrally.

The fuel combustion needs sufficient oxygen quantity, and the staged air distribution is to send the oxygen quantity into the combustion area in stages, so that the over-high temperature caused by over-concentrated fuel combustion can be avoided, and simultaneously, the oxygen quantity is high, and a large amount of NOx can be generated. After the air distribution in a grading way, the oxygen is insufficient in a combustion area, and the combustion area is in a reducing atmosphere, so that the generation of NOx is favorably inhibited.

The excess air factor is also referred to as "excess air factor" and "excess air factor", and is commonly referred to as "residual air factor". Refers to the ratio of the amount of air actually supplied to the fuel for combustion to the theoretical amount of air. Is an important parameter reflecting the fuel to air ratio.

The first combustion chamber 2 is controlled to be in an oxygen-deficient environment overall, fuel cannot be burnt out, meanwhile, no heating surface is arranged, the second combustion chamber 3 is a main body part of the boiler, the heating surface is arranged to absorb heat released after the fuel is burnt, the fuel which is not burnt out in the first combustion chamber enters the second combustion chamber, and meanwhile, oxygen required by the combustion of the residual fuel is supplemented through the feeding of burning-out air, so that the effects of burning out and reducing NOx are achieved.

In this embodiment, main combustion apparatus is buggy or hydrocarbon fuel cyclone burner including primary air and overgrate air, cyclone burner 1 connects afterwards first combustion chamber 2, buggy or hydrocarbon fuel begin to burn in first combustion chamber 2, produce high temperature flame, lay refractory material in the first combustion chamber 2, make inside the first combustion chamber 2 keep at 1000 ~ 1200 ℃ at least within range, mix simultaneously from 2 axial of first combustion chamber and circumference and burn the ammonia, the high temperature environment is favorable to the stable burning of ammonia mixing back flame, connect second combustion chamber 3 after first combustion chamber 2, mix the over fire air in second combustion chamber 3, guarantee that all fuels are fully burnt out.

Example 2:

as shown in fig. 2, 4 and 5, the main difference between the present embodiment and embodiment 1 is that the first combustion chamber 2 is shaped as a hollow right quadrangular prism, and the cross section thereof is rectangular; the second combustion chamber 3 is arranged vertically, and the over-fire air duct 4 is located at the side of the second combustion chamber 3 and injects over-fire air into the second combustion chamber 3 in the horizontal direction. As shown in FIG. 4, each stage of ammonia jets is circumferentially distributed with 8 ammonia jets.