CN220249978U - Ammonia and pulverized coal premixing energy-saving combustion device - Google Patents
Ammonia and pulverized coal premixing energy-saving combustion device Download PDFInfo
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- CN220249978U CN220249978U CN202321805129.0U CN202321805129U CN220249978U CN 220249978 U CN220249978 U CN 220249978U CN 202321805129 U CN202321805129 U CN 202321805129U CN 220249978 U CN220249978 U CN 220249978U
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- Prior art keywords
- ammonia
- coal
- exhaust fan
- smoke exhaust
- communicated
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- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 title claims abstract description 111
- 239000003245 coal Substances 0.000 title claims abstract description 66
- 229910021529 ammonia Inorganic materials 0.000 title claims abstract description 35
- 238000002485 combustion reaction Methods 0.000 title claims abstract description 27
- 239000000779 smoke Substances 0.000 claims abstract description 38
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims abstract description 20
- 239000003546 flue gas Substances 0.000 claims abstract description 20
- 230000003197 catalytic effect Effects 0.000 claims abstract description 13
- 238000000605 extraction Methods 0.000 claims abstract description 13
- 230000001105 regulatory effect Effects 0.000 claims description 25
- 229910000831 Steel Inorganic materials 0.000 claims description 5
- 239000003054 catalyst Substances 0.000 claims description 5
- 239000010959 steel Substances 0.000 claims description 5
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 4
- 239000001301 oxygen Substances 0.000 claims description 4
- 229910052760 oxygen Inorganic materials 0.000 claims description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 4
- 229910000851 Alloy steel Inorganic materials 0.000 claims description 3
- 238000002156 mixing Methods 0.000 abstract description 13
- 229910000069 nitrogen hydride Inorganic materials 0.000 abstract description 13
- 239000000843 powder Substances 0.000 abstract description 6
- 230000000694 effects Effects 0.000 abstract description 5
- 239000000463 material Substances 0.000 abstract description 5
- 238000004880 explosion Methods 0.000 abstract description 4
- 238000005507 spraying Methods 0.000 abstract description 4
- 239000002699 waste material Substances 0.000 abstract description 4
- 239000007789 gas Substances 0.000 abstract description 3
- 238000004064 recycling Methods 0.000 abstract description 3
- 239000004449 solid propellant Substances 0.000 abstract description 2
- 230000006872 improvement Effects 0.000 description 9
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 7
- 239000002817 coal dust Substances 0.000 description 4
- 239000000446 fuel Substances 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000010344 co-firing Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 238000006479 redox reaction Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 239000000295 fuel oil Substances 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000006722 reduction reaction Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E20/00—Combustion technologies with mitigation potential
- Y02E20/34—Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery
Abstract
The utility model discloses an ammonia and pulverized coal premixing energy-saving combustion device, which comprises a hearth, a coal mill, a smoke exhaust fan and an air fan, wherein the hearth is connected with a denitration catalytic reactor through a flue; a burner is arranged in the hearth; the output end of the coal mill is connected with the burner; a flue at the outlet of the denitration catalytic reactor is provided with a flue gas extraction port; the input end of the smoke exhaust fan is communicated with the smoke extraction port, and the output end of the smoke exhaust fan is communicated with the input end of the coal mill; the input end of the air blower is communicated with the external atmospheric environment, and the output end of the air blower is communicated with the input end of the coal mill. The device solves the problems of uneven mixing of gas and solid fuels and poor NH3 ignition effect of the existing ammonia/coal powder mixing and burning equipment, simultaneously eliminates the explosion risk caused by directly spraying high-concentration NH3 into the coal powder burner of the existing mixing and burning equipment, and finally has the advantages of recycling waste ammonia and heat in the flue gas after denitration and saving materials and energy.
Description
Technical Field
The utility model relates to the technical field of novel combustion of thermal power generating units, in particular to an ammonia gas and pulverized coal premixing energy-saving combustion device.
Background
The coal-fired boiler aims at energy conservation and carbon reduction, and is fully feasible by mixing and burning ammonia gas with a certain proportion.
Related researches show that the ignition temperature of NH3 is about 850 ℃, and meanwhile, the combustion flame of ammonia in the air is slow to propagate, and the combustion is unstable, so that NH3 is not easy to ignite in the air. The ignition temperature was about 600℃in the presence of an iron-based catalyst. NH3 can ignite in air at higher temperatures or in the presence of a catalyst, and in a certain concentration range (15.7-25.4%) can explode. Therefore, the coal dust is mixed by utilizing the high-temperature flue gas containing ammonia, and the safe mixing and the safe conveying can be realized as long as the temperature and the ammonia concentration are controlled.
Disclosure of Invention
Aiming at the defects existing in the prior art, the utility model aims to provide an ammonia and pulverized coal premixing energy-saving combustion device, which solves the problems of uneven mixing of gas and solid fuels and poor NH3 ignition effect of the existing ammonia/pulverized coal mixing and burning equipment, simultaneously eliminates the explosion risk caused by directly spraying high-concentration NH3 into a pulverized coal burner of the existing mixing and burning equipment, and finally, the device also has the advantages of recycling waste ammonia and heat in the flue gas after denitration and saving materials and energy.
In order to achieve the above purpose, the utility model adopts the following technical scheme: the ammonia and pulverized coal premixing energy-saving combustion device comprises a hearth, a coal mill, a smoke exhaust fan and an air fan, wherein the hearth is connected with a denitration catalytic reactor through a flue; a burner is arranged in the hearth; the output end of the coal mill is connected with the burner; a flue at the outlet of the denitration catalytic reactor is provided with a flue gas extraction port; the input end of the smoke exhaust fan is communicated with the smoke extraction port, and the output end of the smoke exhaust fan is communicated with the input end of the coal mill; the input end of the air blower is communicated with the external atmospheric environment, and the output end of the air blower is communicated with the input end of the coal mill.
The further improvement is that: and a first regulating valve is arranged between the smoke exhaust fan and the coal mill and used for regulating the flow of smoke and meeting the requirements of the coal mill under different output forces.
The further improvement is that: and a second regulating valve is arranged between the air blower and the coal mill and is used for regulating the inlet air flow temperature of the coal mill and the oxygen content in the air flow.
The further improvement is that: the input end of the smoke exhaust fan is also communicated with an external ammonia gas source.
The further improvement is that: and a third regulating valve is arranged between the smoke exhaust fan and an external ammonia gas source and used for regulating the addition amount of the extra ammonia gas.
The further improvement is that: the smoke exhaust fan and the air fan are both high-pressure centrifugal fans.
The further improvement is that: the ammonia escape tap is a steel smoke extraction port.
The further improvement is that: the flue is a square tubular flue gas channel made of steel plates.
The further improvement is that: the denitration catalytic reactor is provided with 2 layers or 3 layers of SCR catalysts.
The further improvement is that: the hearth is a square tubular space formed by water wall pipes; the burner is of a medium-pass circular tube or square tube structure made of high-temperature alloy steel and is uniformly arranged at four sides of a furnace wall or corner positions of a hearth.
The utility model has the beneficial effects that:
1. compared with the existing ammonia/pulverized coal mixed combustion technology, the utility model fully utilizes the denitration waste ammonia of the thermal power plant and saves the materials of the power plant.
2. Compared with the existing ammonia/coal powder mixing combustion technology, the utility model solves the problems of uneven mixing, poor NH3 ignition effect, explosion risk caused by directly spraying high-concentration NH3 and the like existing in the existing ammonia spraying at the burner by using a method of pre-mixing gas and solid in a coal pulverizing system. The utility model greatly increases the safety of ammonia co-firing and provides co-firing effect.
Drawings
FIG. 1 is a schematic structural diagram of an ammonia gas and pulverized coal premixing energy-saving combustion device in an embodiment of the utility model.
Reference numerals:
1-a burner; 2-a hearth; 3-denitration catalytic reactor; 4-flue; 5-a smoke extraction port; 6, a smoke exhaust fan; 61-a first regulating valve; 7-an air blower; 71-a second regulating valve; 8-a third regulating valve; 9-coal mill.
Detailed Description
Embodiments of the present utility model are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout.
In the description of the present utility model, it should be noted that, for the azimuth words such as the terms "center", "transverse (X)", "longitudinal (Y)", "vertical (Z)", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., the azimuth and positional relationships are based on the azimuth or positional relationships shown in the drawings, only for convenience of describing the present utility model and simplifying the description, but do not indicate or imply that the apparatus or element to be referred to must have a specific azimuth, be constructed and operated in a specific azimuth, and should not be construed as limiting the specific protection scope of the present utility model.
Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features. Thus, the definition of "a first", "a second" feature may explicitly or implicitly include one or more of such feature, and in the description of the present utility model, the meaning of "a number", "a number" is two or more, unless otherwise specifically defined.
The technical scheme and the beneficial effects of the utility model are more clear and definite by further describing the specific embodiments of the utility model with reference to the drawings in the specification. The embodiments described below are exemplary by referring to the drawings for the purpose of illustrating the utility model and are not to be construed as limiting the utility model.
Referring to fig. 1, the embodiment of the utility model provides an ammonia and pulverized coal premixing energy-saving combustion device, which comprises a hearth 2, wherein the hearth 2 is connected with a denitration catalytic reactor 3 through a flue 4, and the flue 4 is a square tubular flue gas channel made of steel plates.
The ammonia and pulverized coal premixing energy-saving combustion device also comprises a coal mill 9, a smoke exhaust fan 6 and an air fan 7; a burner 1 is arranged in the hearth 2; specifically, the hearth 2 is a square tubular space formed by water wall pipes, and fuels such as coal dust, fuel oil, natural gas and the like burn in the square tubular space to release heat; the burner 1 is of a medium-pass circular tube or square tube structure made of high-temperature alloy steel, is uniformly arranged at four sides of a furnace wall or corner positions of the hearth 2, and is mainly used for mixing pulverized coal and air and organizing a reasonable flow field to ensure pulverized coal combustion.
The output end of the coal mill 9 is connected with the burner 1; and mechanical equipment for crushing coal blocks into coal powder with a certain particle size by adopting collision, grinding and other modes. The pulverized coal is carried by the air flow, enters the burner and is sent into the hearth for combustion.
A flue 4 at the outlet of the denitration catalytic reactor 3 is provided with a flue gas extraction port 5; specifically, the ammonia escape tap is a steel smoke extraction port, and the smoke containing unreacted NH3 is extracted from the smoke extraction port for recycling. The denitration catalytic reactor 3 is provided with 2 or 3 layers of SCR catalysts, where the flue gas containing nitrogen oxides (NOx) undergoes oxidation-reduction reaction, generating nitrogen and water.
The input end of the smoke exhaust fan 6 is communicated with the smoke extraction port 5, and the output end of the smoke exhaust fan 6 is communicated with the input end of the coal mill 9; specifically, a first regulating valve 61 is arranged between the smoke exhaust fan 6 and the coal mill 9 and is used for regulating the flow of smoke so as to meet the requirements of the coal mill 9 under different output forces. The input end of the smoke exhaust fan 6 is also communicated with an external ammonia gas source. A third regulating valve 8 is arranged between the smoke exhaust fan 6 and an external ammonia gas source and is used for regulating the addition amount of the extra ammonia gas. The content of the denitration waste ammonia in the flue gas is low, the flow of the ammonia gas is required to be additionally increased in order to meet the requirement of large-proportion doping combustion, and the third regulating valve 8 has the function of regulating the addition amount of NH 3.
The input end of the air blower 7 is communicated with the external atmospheric environment, and the output end of the air blower 7 is communicated with the input end of the coal mill 9. Specifically, a second regulating valve 71 is arranged between the air blower 7 and the coal mill 9, and is used for regulating the inlet airflow temperature of the coal mill 9 and the oxygen content in the airflow. Specifically, the smoke exhaust fan 6 and the air fan 7 are high-pressure centrifugal fans, and can adapt to high-temperature operation.
The working principle of the utility model is as follows:
the working process comprises the following steps: after the boiler is ignited, coal powder burns and releases heat in the hearth to generate a great amount of high-temperature flue gas containing NOx, and the flue gas flows from the hearth to the tail flue under the action of a blower and a draught fan.
Flows to the area of the coal economizer to the denitration catalytic reactor to complete the oxidation-reduction reaction. The flue gas after denitration still contains a part of unreacted complete NH3, at the moment, the flue gas containing NH3 is sent to the coal mill through the suction of the flue gas fan from the flue gas extraction port on the flue gas outlet flue of denitration, and is used for drying and carrying pulverized coal. When the boiler load reaches a certain value, the regulating valve can be opened, the ammonia supply amount is increased, and the high-proportion ammonia co-combustion is realized.
To ensure combustion of the ammonia/pulverized coal mixture, it is necessary to increase the oxygen content in the air stream entering the coal mill and to reduce the air stream temperature, avoid NH3 explosions, and to increase the supply of cold air by opening the regulating valve 71. Thereby meeting the safety operation requirement of the coal mill.
The ammonia gas and the ammonia-containing flue gas are mixed strongly through the smoke exhaust fan and are used as powder carrying air flow to dry coal dust, and air flow rotation impact is carried out in a coal mill, so that the pre-mixing of the ammonia gas/coal dust gas-solid two-phase fuel to a higher degree is realized, and the ignition effect of the mixed fuel at the burner is greatly improved.
In the description of the present utility model, a description of the terms "one embodiment," "preferred," "example," "specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the utility model, and a schematic representation of the terms described above in the present specification does not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
From the above description of the structure and principles, it should be understood by those skilled in the art that the present utility model is not limited to the above-described embodiments, but rather that modifications and substitutions using known techniques in the art on the basis of the present utility model fall within the scope of the present utility model, which is defined by the appended claims.
Claims (9)
1. The utility model provides an ammonia and energy-conserving burner of buggy premixing, includes furnace (2), furnace (2) link to each other with denitration catalytic reactor (3) through flue (4), its characterized in that: the device also comprises a coal mill (9), a smoke exhaust fan (6) and an air fan (7);
a burner (1) is arranged in the hearth (2);
the output end of the coal mill (9) is connected with the burner (1);
a flue (4) at the outlet of the denitration catalytic reactor (3) is provided with a flue gas extraction port (5);
the input end of the smoke exhaust fan (6) is communicated with the smoke extraction port (5), and the output end of the smoke exhaust fan (6) is communicated with the input end of the coal mill (9);
the input end of the air blower (7) is communicated with the external atmospheric environment, and the output end of the air blower (7) is communicated with the input end of the coal mill (9).
2. The ammonia and pulverized coal premixing energy-saving combustion apparatus as set forth in claim 1, wherein: a first regulating valve (61) is arranged between the smoke exhaust fan (6) and the coal mill (9) and is used for regulating the flow of smoke and meeting the requirements of the coal mill (9) under different output.
3. The ammonia and pulverized coal premixing energy-saving combustion apparatus as set forth in claim 1, wherein: a second regulating valve (71) is arranged between the air blower (7) and the coal mill (9) and is used for regulating the inlet air flow temperature of the coal mill (9) and the oxygen content in the air flow.
4. The ammonia and pulverized coal premixing energy-saving combustion apparatus as set forth in claim 1, wherein: the input end of the smoke exhaust fan (6) is also communicated with an external ammonia gas source.
5. The ammonia and pulverized coal premixing energy-saving combustion apparatus as set forth in claim 1, wherein: a third regulating valve (8) is arranged between the smoke exhaust fan (6) and an external ammonia gas source and is used for regulating the addition amount of extra ammonia gas.
6. The ammonia and pulverized coal premixing energy-saving combustion apparatus as set forth in claim 1, wherein: the smoke exhaust fan (6) and the air fan (7) are both high-pressure centrifugal fans.
7. The ammonia and pulverized coal premixing energy-saving combustion apparatus as set forth in claim 1, wherein: the flue (4) is a square tubular flue gas channel made of steel plates.
8. The ammonia and pulverized coal premixing energy-saving combustion apparatus as set forth in claim 1, wherein: the denitration catalytic reactor (3) is provided with 2 layers or 3 layers of SCR catalysts.
9. The ammonia and pulverized coal premixing energy-saving combustion apparatus as set forth in claim 1, wherein: the hearth (2) is a square tubular space formed by water wall pipes; the burner (1) is of a medium-through type circular tube or square tube structure made of high-temperature resistant alloy steel and is uniformly arranged at four-side furnace walls or corner positions of the hearth (2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321805129.0U CN220249978U (en) | 2023-07-11 | 2023-07-11 | Ammonia and pulverized coal premixing energy-saving combustion device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321805129.0U CN220249978U (en) | 2023-07-11 | 2023-07-11 | Ammonia and pulverized coal premixing energy-saving combustion device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN220249978U true CN220249978U (en) | 2023-12-26 |
Family
ID=89262580
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202321805129.0U Active CN220249978U (en) | 2023-07-11 | 2023-07-11 | Ammonia and pulverized coal premixing energy-saving combustion device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN220249978U (en) |
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2023
- 2023-07-11 CN CN202321805129.0U patent/CN220249978U/en active Active
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