CN111750373B - A flue gas recirculation system for preventing spontaneous combustion of pulverized coal in the pulverized coal pipeline of a medium-speed coal mill - Google Patents
A flue gas recirculation system for preventing spontaneous combustion of pulverized coal in the pulverized coal pipeline of a medium-speed coal mill Download PDFInfo
- Publication number
- CN111750373B CN111750373B CN202010790380.9A CN202010790380A CN111750373B CN 111750373 B CN111750373 B CN 111750373B CN 202010790380 A CN202010790380 A CN 202010790380A CN 111750373 B CN111750373 B CN 111750373B
- Authority
- CN
- China
- Prior art keywords
- coal
- pipeline
- flue gas
- powder
- recirculation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000003245 coal Substances 0.000 title claims abstract description 128
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 title claims abstract description 70
- 239000003546 flue gas Substances 0.000 title claims abstract description 70
- 238000002485 combustion reaction Methods 0.000 title claims abstract description 24
- 230000002269 spontaneous effect Effects 0.000 title claims abstract description 18
- 239000000843 powder Substances 0.000 claims abstract description 82
- 238000004064 recycling Methods 0.000 claims abstract description 23
- 239000000428 dust Substances 0.000 claims abstract description 21
- 238000002156 mixing Methods 0.000 claims abstract description 20
- 239000002184 metal Substances 0.000 claims description 7
- 230000001105 regulatory effect Effects 0.000 claims description 4
- 238000005507 spraying Methods 0.000 claims description 4
- 229910000831 Steel Inorganic materials 0.000 claims description 3
- 239000012774 insulation material Substances 0.000 claims description 3
- 239000010959 steel Substances 0.000 claims description 3
- 238000005299 abrasion Methods 0.000 claims 1
- 238000004200 deflagration Methods 0.000 abstract description 11
- 239000001301 oxygen Substances 0.000 abstract description 11
- 229910052760 oxygen Inorganic materials 0.000 abstract description 11
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 abstract description 9
- 230000008021 deposition Effects 0.000 abstract description 6
- 239000000779 smoke Substances 0.000 description 18
- 239000002817 coal dust Substances 0.000 description 9
- 238000010298 pulverizing process Methods 0.000 description 3
- 238000001816 cooling Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000004880 explosion Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000010926 purge Methods 0.000 description 1
- 238000009991 scouring Methods 0.000 description 1
- 238000005496 tempering Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23K—FEEDING FUEL TO COMBUSTION APPARATUS
- F23K1/00—Preparation of lump or pulverulent fuel in readiness for delivery to combustion apparatus
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN A CARRIER GAS OR AIR
- F23C5/00—Disposition of burners with respect to the combustion chamber or to one another; Mounting of burners in combustion apparatus
- F23C5/08—Disposition of burners
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN A CARRIER GAS OR AIR
- F23C9/00—Combustion apparatus characterised by arrangements for returning combustion products or flue gases to the combustion chamber
- F23C9/003—Combustion apparatus characterised by arrangements for returning combustion products or flue gases to the combustion chamber for pulverulent fuel
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES
- F23J15/00—Arrangements of devices for treating smoke or fumes
- F23J15/02—Arrangements of devices for treating smoke or fumes of purifiers, e.g. for removing noxious material
- F23J15/022—Arrangements of devices for treating smoke or fumes of purifiers, e.g. for removing noxious material for removing solid particulate material from the gasflow
- F23J15/025—Arrangements of devices for treating smoke or fumes of purifiers, e.g. for removing noxious material for removing solid particulate material from the gasflow using filters
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23K—FEEDING FUEL TO COMBUSTION APPARATUS
- F23K3/00—Feeding or distributing of lump or pulverulent fuel to combustion apparatus
- F23K3/02—Pneumatic feeding arrangements, i.e. by air blast
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23L—SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
- F23L17/00—Inducing draught; Tops for chimneys or ventilating shafts; Terminals for flues
- F23L17/005—Inducing draught; Tops for chimneys or ventilating shafts; Terminals for flues using fans
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
Abstract
The flue gas recirculation system for preventing the spontaneous combustion of accumulated powder in the coal powder pipeline of the medium speed coal mill comprises a medium speed coal mill, a coal-fired boiler, an induced draft fan and a recirculation flue gas pipeline, wherein the coal-fired boiler comprises a combustor, the coal powder pipeline is arranged at the outlet of the medium speed coal mill, the outlet of the coal powder pipeline is connected with the combustor through a mixing pipeline, the coal-fired boiler is connected with the inlet of the induced draft fan, the outlet of the induced draft fan is divided into two paths, one path discharges flue gas, and the other path is communicated with the coal powder pipeline through the recirculation flue gas pipeline. According to the invention, the low-dust low-oxygen flue gas at the outlet of the induced draft fan of the coal-fired power plant boiler is mixed with the air-powder airflow at the outlet of the medium-speed coal mill by arranging the recycling flue gas pipeline, the oxygen content of the mixed medium is reduced to be within 14%, spontaneous combustion of coal powder deposited by the coal powder pipeline is effectively prevented, the condition of deflagration of a coal powder making system is avoided, and the flow speed of the mixed medium is increased by 30% -50%, so that the deposition of coal powder in the medium is prevented. And prevent boiler slagging caused by higher flame temperature in the burner area.
Description
Technical Field
The invention belongs to the field of coal-fired power station boilers, and particularly relates to a flue gas recirculation system for preventing spontaneous combustion of accumulated powder in a coal powder pipeline of a medium-speed coal mill.
Background
The coal-fired power plant boiler pulverizing system has the main functions of preparing qualified coal powder for a boiler and conveying the coal powder to combustion equipment for combustion.
The deflagration of the powder making system needs to meet three conditions simultaneously, namely (1) mixed gas of coal powder and air exists in a limited space, (2) the concentration of the coal powder in the combustible mixture reaches an explosion condition, and (3) open fire for triggering deflagration exists, wherein the open fire for triggering deflagration in operation comes from combustion tempering which occurs when the coal powder in the powder making system is deposited to spontaneous combustion and the speed of primary air outlet and powder of a burner is lower than the flame propagation speed. Deflagration of the pulverizing system is easily caused by powder accumulation and ignition of a pulverized coal pipeline when Indonesia coal and south Africa coal are ground. The reasons for deflagration caused by accumulated powder in the coal powder pipeline of the medium-speed coal mill mainly include that (1) the water content of the coal powder is higher, so that the outlet temperature of the coal mill is lower, when the outlet temperature of the coal mill is close to or lower than a water dew point, the coal powder is easy to deposit in the coal powder pipeline, (2) the air flow speed of the wind powder is lower, so that the coal powder is deposited, (3) accumulated powder is easy to exist at a hoop and an adjustable shrinkage hole on the coal powder pipeline, and (4) the coal powder pipeline is not thoroughly pumped and purged when the coal mill is stopped. The Indonesia coal is generally dried and has no ash-based volatile matter of about 48%, the explosion index K d of the coal is larger, the Indonesia coal belongs to the explosive coal types, the total moisture is about 24%, the moisture is high, the risk of coal dust deposition is increased, when the medium-speed coal mill grinds high-moisture coal types, the outlet temperature of the coal mill is generally 56-62 ℃, and the deflagration risk of a coal dust pipeline is easily increased due to coal dust condensation deposition.
At present, most power plants take measures such as prolonging the purging time of the starting and stopping process of the coal mill, controlling the outlet temperature of the coal mill, increasing the inlet air quantity of the coal mill, and the like, however, the problem of spontaneous combustion of accumulated powder in a coal powder pipeline still occurs, and the problem of deflagration of a powder making system is not thoroughly and radically solved.
Disclosure of Invention
The invention aims to provide a flue gas recirculation system for preventing spontaneous combustion of accumulated powder in a coal powder pipeline of a medium-speed coal mill.
In order to achieve the above purpose, the present invention adopts the following technical scheme:
The flue gas recirculation system for preventing the spontaneous combustion of accumulated powder in the coal powder pipeline of the medium speed coal mill comprises a medium speed coal mill, a coal-fired boiler, an induced draft fan and a recirculation flue gas pipeline, wherein the coal-fired boiler comprises a combustor, the coal powder pipeline is arranged at the outlet of the medium speed coal mill, the outlet of the coal powder pipeline is connected with the combustor through a mixing pipeline, the coal-fired boiler is connected with the inlet of the induced draft fan, the outlet of the induced draft fan is divided into two paths, one path discharges flue gas, and the other path is communicated with the coal powder pipeline through the recirculation flue gas pipeline.
The invention is further improved in that the recirculation flue gas pipeline is provided with a recirculation fan.
A further improvement of the invention is that the recirculation fan is driven by a 380V motor.
The invention is further improved in that the recirculation fan adopts a centrifugal fan, and blades of the centrifugal fan adopt wear-resistant spraying blades.
The invention is further improved in that a dust removing device is arranged on the recycling flue gas pipeline between the outlet of the induced draft fan and the inlet of the recycling fan.
The invention is further improved in that the dust removing device is a metal filter bag.
The invention is further improved in that an electric regulating door, an electric stop door and an adjustable shrinkage cavity are sequentially arranged on a recirculation flue gas pipeline between an outlet of the recirculation fan and a coal dust pipeline at an outlet of the medium speed coal mill.
The invention is further improved in that the coal powder pipeline, the recycling flue gas pipeline and the mixing pipeline are all made of Q235 steel, and heat insulation materials are laid outside the coal powder pipeline, the recycling flue gas pipeline and the mixing pipeline.
Compared with the prior art, the invention has the beneficial effects that:
according to the invention, the low-dust low-oxygen flue gas at the outlet of the induced draft fan of the coal-fired power plant boiler is mixed with the air-powder airflow at the outlet of the medium-speed coal mill by arranging the recycling flue gas pipeline, the oxygen content of the mixed medium is reduced to be within 14%, spontaneous combustion of coal powder deposited by the coal powder pipeline is effectively prevented, the condition of deflagration of a coal powder making system is avoided, and the flow speed of the mixed medium is increased by 30% -50%, so that the deposition of coal powder in the medium is prevented. When the medium speed coal mill stops operating, the flue gas at the outlet of the induced draft fan still enters the burner through the recirculation pipeline, the recirculation fan and the mixing pipeline, and on one hand, the cooling effect is achieved on the burner nozzle, so that the corresponding burner nozzle is prevented from burning loss and deformation when the medium speed coal mill stops operating, on the other hand, the flame temperature of a hearth can be reduced, the NOx generated by combustion is reduced, and meanwhile, boiler slagging caused by high flame temperature in a burner area is prevented.
Drawings
FIG. 1 is a schematic diagram of a flue gas recirculation system for preventing spontaneous combustion of accumulated powder in a coal powder pipeline of a medium speed coal mill;
Wherein, 1 is medium speed coal mill, 2 is coal fired boiler, 3 is the dust remover, 4 is the draught fan, 5 is the recirculation fan, 6 is the buggy pipeline, 7 is the hybrid channel, 8 is the combustor, 9 is the recirculation flue gas pipeline, 10 is electric control door, 11 is electric stop door, 12 is adjustable shrinkage cavity, 13 is the metal filter bag.
Detailed Description
The invention is described in further detail below with reference to the accompanying drawings.
Referring to fig. 1, the flue gas recirculation system for preventing spontaneous combustion of accumulated powder in a coal powder pipeline of a medium speed coal mill comprises a medium speed coal mill 1, a coal-fired boiler 2, a dust remover 3, an induced draft fan 4 and a recirculation flue gas pipeline 9. The coal-fired boiler 2 includes combustor 8, and medium speed coal pulverizer 1 exit is provided with coal powder pipeline 6, and coal powder pipeline 6 export links to each other with combustor 8 through mixing tube 7, and coal-fired boiler 2 links to each other with draught fan 4 entry through dust remover 3, and the export of draught fan 4 divide into two ways, and exhaust flue gas is gone out to one way, and another way is linked together with coal powder pipeline 6 through recycling flue gas pipeline 9. Specifically, the pulverized coal pipeline 6 of the medium speed coal mill 1 is communicated with the recirculated flue gas pipeline 9, and the flue gas in the recirculated flue gas pipeline 9 is mixed with pulverized coal and wind in the pulverized coal pipeline 6 and then is connected with the combustor 8 through the mixing pipeline 7.
A recirculation fan 5 is arranged on the recirculation flue gas pipeline 9. The recirculation fan 5 is driven by a 380V motor, the recirculation fan 5 adopts a centrifugal fan, and blades of the recirculation fan 5 adopt wear-resistant spraying blades.
According to the invention, part of flue gas is extracted from the outlet flue of the induced draft fan 4, the flue gas flows through the recirculation fan 5 through the recirculation flue gas pipeline 9, the pressure of the flue gas is increased through the recirculation fan 5, and the flue gas is introduced into the four coal dust pipelines 6 at the outlet of the medium-speed coal mill 1 through the recirculation flue gas pipeline 9, so that the flue gas at the outlet of the induced draft fan 4 is mixed with wind dust air flow and then enters the combustor 8 through the mixing pipeline 7 for combustion.
The dust removing device is arranged on the recycling flue gas pipeline 9 from the outlet of the induced draft fan 4 to the inlet of the recycling fan 5, and the dust removing device is a metal filter bag 13.
In order to meet the explosion-proof requirement of the boiler, an electric adjusting door 10 and an electric stop door 11 are sequentially arranged on a recirculation flue gas pipeline 9 between the outlet of the recirculation fan 5 and the coal dust pipeline 6 at the outlet of the medium speed coal mill 1 so as to adjust shrinkage holes 12.
The coal powder pipeline 6, the recycling flue gas pipeline 9 and the mixing pipeline 7 are made of Q235 steel, and heat insulation materials are laid outside the coal powder pipeline 6, the recycling flue gas pipeline 9 and the mixing pipeline 7.
Due to the different capacities of the unit and the output of the coal mill, the temperature of the air-powder airflow in the outlet coal powder pipeline is within the range of 55-95 ℃ when the medium-speed coal mill is in operation, the pressure of the air-powder airflow is 2-3 kPa, the oxygen content in the air-powder airflow is 21%, and the flow speed of the air-powder airflow is 18-28 m/s. The temperature of flue gas at the outlet of an induced draft fan of the coal-fired power plant boiler is 95-120 ℃, the pressure of the flue gas at the outlet of the induced draft fan is 0.8-2 kPa, and the oxygen content in the flue gas is 4-6%.
And extracting smoke from an outlet flue of the induced draft fan, sending the smoke into an inlet of the recirculation fan through a recirculation smoke pipeline, wherein the smoke pressure at the inlet of the recirculation fan is 0.8 kPa-2.5 kPa, the dust content in the smoke is within 30mg/m 3, the dust content is reduced to about 5mg/m 3 after flowing through a metal filter bag arranged on the recirculation smoke pipeline, the smoke subjected to dust removal treatment of the metal filter bag flows through the recirculation fan, the smoke pressure is increased to about 3.5kPa, and after the pressurized smoke passes through the recirculation smoke pipeline, an electric regulating door, an electric stop door and an adjustable shrinkage cavity, the smoke pressure is regulated to be slightly higher than the air-dust air pressure, and the smoke is respectively introduced into four coal dust pipelines at the outlet of the medium-speed coal mill to be mixed with the air-dust air flow.
The oxygen content of the flue gas at the outlet of the induced draft fan is 4-6%, the oxygen content of the air flow of the air powder at the outlet of the medium speed coal mill is 21%, and the oxygen content of the mixed medium is 12-13%, so that the requirement that the maximum allowable oxygen content of the outlet of the system coal mill designed according to inert atmosphere is not more than 14% in DL/T5203-2005 explosion-proof design rules of coal and pulverizing systems of thermal power plants is met. Even if coal dust deposition exists in a medium in the mixing pipeline, the phenomenon of spontaneous combustion of accumulated coal can not occur, and the condition of deflagration of the coal mill can not be achieved.
The flue gas is mixed with the air flow of the wind powder, the temperature of the mixed medium is 75-107 ℃, although the temperature of the mixed medium is higher than that of the air flow of the wind powder by 12-20 ℃, the initial ignition of the coal powder in the mixed medium entering the burner is facilitated, and the mixed medium is inert atmosphere in consideration of the oxygen content of the mixed medium being less than 14%, so that the deflagration of the coal mill cannot occur due to the increase of the temperature of the medium.
The flue gas is mixed with the wind powder air flow, the flow speed of the mixed medium is improved by 30% -50%, and the risk of coal dust deposition in the mixed medium is reduced. The mixing pipeline is connected with a coal powder nozzle of the burner, and the mixed medium enters a hearth for burning after passing through the burner.
Further, as the dust content in the flue gas at the outlet of the induced draft fan is within 30mg/m 3, although the dust is removed by the metal filter bag 13, the dust content in the flue gas is still about 5mg/m 3, and in order to prevent the dust in the flue gas from scouring and wearing the blades of the recirculation fan, the blades of the recirculation fan adopt wear-resistant spraying blades. The inlet smoke pressure of the recirculation fan is 0.8-2 kPa, the outlet smoke pressure is 3.5kPa, and the inlet-outlet pressure difference of the recirculation fan is 1.5-2.7 kPa, so the recirculation fan adopts a centrifugal fan, and the motor of the recirculation fan is a 380V piezoelectric motor.
Furthermore, in order to ensure that the flue gas flow deviation of four coal powder pipelines entering the outlet of the medium speed coal mill is within +/-5 percent, adjustable shrinkage cavities are arranged on the recirculation pipelines between the recirculation fan and the coal powder pipelines so as to balance the flue gas flow deviation among the recirculation pipelines. In order to ensure that the flow deviation of the medium after the flue gas and the wind powder air flow are mixed is within +/-5 percent, adjustable shrinkage cavities are arranged on the mixing pipelines so as to balance the flow deviation among the four mixing pipelines.
Further, when the medium speed coal mill stops operating, the electric stop door arranged on the coal powder pipeline is closed, the electric stop door on the recycling pipeline is in a full-open state, the recycling fan still operates, the electric adjustment door keeps proper opening, smoke enters the hearth through the recycling pipeline, the mixing pipeline and the burner nozzle, on one hand, the temperature of the recycling smoke is 95-120 ℃, the cooling effect is achieved on the nozzle when the smoke flows through the burner, the burning deformation of the corresponding burner nozzle when the medium speed coal mill stops operating is prevented, on the other hand, the smoke at the outlet of the induced draft fan enters the hearth through the recycling pipeline, the mixing pipeline and the burner, the flame temperature of the hearth can be reduced, the NOx generated by combustion is reduced, and meanwhile, boiler slagging caused by the high flame temperature of the burner area is prevented.
Claims (5)
1. The flue gas recirculation system for preventing the spontaneous combustion of the accumulated powder of the coal powder pipeline of the medium speed coal mill is characterized by comprising the medium speed coal mill (1), a coal-fired boiler (2), an induced draft fan (4) and a recirculation flue gas pipeline (9), wherein the coal-fired boiler (2) comprises a combustor (8), the coal powder pipeline (6) is arranged at the outlet of the medium speed coal mill (1), the outlet of the coal powder pipeline (6) is connected with the combustor (8) through a mixing pipeline (7), the coal-fired boiler (2) is connected with the inlet of the induced draft fan (4), the outlet of the induced draft fan (4) is divided into two paths, one path discharges flue gas, and the other path is communicated with the coal powder pipeline (6) through the recirculation flue gas pipeline (9);
the recycling flue gas pipeline (9) is provided with a recycling fan (5), the recycling fan (5) adopts a centrifugal fan, and the recycling fan blade (5) adopts an anti-abrasion spraying blade;
An electric regulating door (10), an electric stop door (11) and an adjustable shrinkage cavity (12) are sequentially arranged on a recirculation flue gas pipeline (9) between the outlet of the recirculation fan (5) and a coal powder pipeline (6) at the outlet of the medium speed coal mill (1), and the coal powder pipeline is provided with the electric stop door (11);
When the medium speed coal mill stops operating, an electric stop door (11) on the coal powder pipeline is closed, the electric stop door (11) on the recycling flue gas pipeline (9) is in a fully opened state, the recycling fan (5) operates, the electric adjustment door (10) keeps proper opening degree, and flue gas enters the hearth through the recycling pipeline, the mixing pipeline and the burner nozzle.
2. A flue gas recirculation system for preventing spontaneous combustion of pulverized coal in a pulverized coal pipe of a medium speed coal mill according to claim 1, characterized in that the recirculation fan (5) is driven by a 380V motor.
3. The flue gas recirculation system for preventing spontaneous combustion of pulverized coal accumulated in a pulverized coal pipeline of a medium speed coal mill according to claim 1, wherein a dust removal device is arranged on a recirculation flue gas pipeline (9) between an outlet of a draught fan (4) and an inlet of a recirculation fan (5).
4. A flue gas recirculation system for preventing spontaneous combustion of pulverized coal in a pulverized coal pipe of a medium speed coal mill according to claim 3, characterized in that the dust removing means is a metal filter bag (13).
5. The flue gas recirculation system for preventing spontaneous combustion of pulverized coal pipeline accumulated powder of a medium speed coal mill according to claim 1, wherein the pulverized coal pipeline (6), the recirculation flue gas pipeline (9) and the mixing pipeline (7) are all made of Q235 steel, and heat insulation materials are laid outside the pulverized coal pipeline (6), the recirculation flue gas pipeline (9) and the mixing pipeline (7).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010790380.9A CN111750373B (en) | 2020-08-07 | 2020-08-07 | A flue gas recirculation system for preventing spontaneous combustion of pulverized coal in the pulverized coal pipeline of a medium-speed coal mill |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010790380.9A CN111750373B (en) | 2020-08-07 | 2020-08-07 | A flue gas recirculation system for preventing spontaneous combustion of pulverized coal in the pulverized coal pipeline of a medium-speed coal mill |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111750373A CN111750373A (en) | 2020-10-09 |
| CN111750373B true CN111750373B (en) | 2025-02-14 |
Family
ID=72713206
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010790380.9A Active CN111750373B (en) | 2020-08-07 | 2020-08-07 | A flue gas recirculation system for preventing spontaneous combustion of pulverized coal in the pulverized coal pipeline of a medium-speed coal mill |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111750373B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113048507A (en) * | 2021-05-13 | 2021-06-29 | 西安热工研究院有限公司 | Flue gas recirculation system for preventing low-temperature corrosion of four-corner tangential pulverized coal fired boiler |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102865588A (en) * | 2012-10-22 | 2013-01-09 | 大唐甘肃发电有限公司 | Middle warehouse type powder making system with low temperature smoke as drying agent and nitrogen as isolation layer |
| CN206739283U (en) * | 2017-04-21 | 2017-12-12 | 西安西热节能技术有限公司 | A kind of depth peak regulation preheats low-load combustion-stabilizing combustion system with heat smoke |
| CN111256107A (en) * | 2020-03-31 | 2020-06-09 | 国电南京电力试验研究有限公司 | Explosion-proof system for grinding high-volatile coal by double-inlet and double-outlet coal mill and working method |
| CN212408718U (en) * | 2020-08-07 | 2021-01-26 | 西安热工研究院有限公司 | Flue gas recirculation system for preventing accumulated powder of coal powder pipeline of medium-speed coal mill from spontaneous combustion |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19707561A1 (en) * | 1997-02-26 | 1998-08-27 | Mitteldeutsche Feuerungs Und U | Method of dry-pulverising coal with coal-dust pulveriser |
| RU108820U1 (en) * | 2011-06-10 | 2011-09-27 | Сергей Валерьевич Гах | BOILER DUST MANAGEMENT SYSTEM |
| JP6019565B2 (en) * | 2011-11-16 | 2016-11-02 | 株式会社Ihi | Fine powder fuel supply method for oxyfuel boiler and oxyfuel boiler system |
| CN105864748A (en) * | 2016-04-19 | 2016-08-17 | 上海理工大学 | Combined combustion system of chain boiler |
| CN106247368B (en) * | 2016-07-29 | 2018-07-17 | 上海交通大学 | A kind of industrial coal powder boiler flue gas recirculation low nitrogen burning method and system |
| CN108006689A (en) * | 2016-11-02 | 2018-05-08 | 中国电力工程顾问集团华北电力设计院有限公司 | A kind of medium-speed milling pulverization system and temperature control control oxygen method suitable for predrying lignite |
| CN208475369U (en) * | 2018-05-30 | 2019-02-05 | 四川广安发电有限责任公司 | Coal-burning boiler pulverized coal preparation system |
| CN110822418A (en) * | 2019-11-11 | 2020-02-21 | 新疆新能集团有限责任公司乌鲁木齐电力建设调试所 | Low temperature flue gas recirculation system and method for low NOX under low load of π-type boiler |
-
2020
- 2020-08-07 CN CN202010790380.9A patent/CN111750373B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102865588A (en) * | 2012-10-22 | 2013-01-09 | 大唐甘肃发电有限公司 | Middle warehouse type powder making system with low temperature smoke as drying agent and nitrogen as isolation layer |
| CN206739283U (en) * | 2017-04-21 | 2017-12-12 | 西安西热节能技术有限公司 | A kind of depth peak regulation preheats low-load combustion-stabilizing combustion system with heat smoke |
| CN111256107A (en) * | 2020-03-31 | 2020-06-09 | 国电南京电力试验研究有限公司 | Explosion-proof system for grinding high-volatile coal by double-inlet and double-outlet coal mill and working method |
| CN212408718U (en) * | 2020-08-07 | 2021-01-26 | 西安热工研究院有限公司 | Flue gas recirculation system for preventing accumulated powder of coal powder pipeline of medium-speed coal mill from spontaneous combustion |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111750373A (en) | 2020-10-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN203223912U (en) | Intermediate storage type super nitrogen reduction system for coal-fired boiler coal mill | |
| CN209495349U (en) | A kind of biomass molding fuel and coal direct-coupling pulverized coal preparation system | |
| CN105987379B (en) | Boiler controller system | |
| CN110220211B (en) | Device and method for cooperatively controlling load of coal-fired boiler by utilizing coupling of coal and gas | |
| CN212408718U (en) | Flue gas recirculation system for preventing accumulated powder of coal powder pipeline of medium-speed coal mill from spontaneous combustion | |
| CN113457791A (en) | Online automatic optimization method for operating parameters of medium-speed coal mill for high-moisture coal | |
| CN101725994B (en) | Exhaust gas and hot-blast air dual-medium powder feeding system | |
| CN111750373B (en) | A flue gas recirculation system for preventing spontaneous combustion of pulverized coal in the pulverized coal pipeline of a medium-speed coal mill | |
| CN106391284A (en) | System for adjusting oxygen concentration in coal grinder and control method | |
| CN112268296A (en) | Primary air control system capable of realizing online monitoring and intelligent adjustment and operation method | |
| CN104048308B (en) | The system and method that low-load for coal pulverizer operates | |
| CN104154532A (en) | Center air ring concentrated type turbulent burner | |
| CN110404650B (en) | Coal grinding system and method for safely and efficiently preparing lignite | |
| CN214974770U (en) | Explosion-proof system for pulverizing of thermal power plant | |
| CN107013907A (en) | A kind of pulverized-coal fired boiler waste heat from tail gas for pulverized coal preparation utilizes system | |
| CN214468721U (en) | Air supply system for gasified air of electric dust removal ash bucket | |
| CN111964928B (en) | Unilateral exhaust smoke temperature rise test method for treating blockage of air preheater | |
| CN210568560U (en) | Device for cooperatively controlling load of coal-fired boiler by coupling coal and gas | |
| CN113446618A (en) | Direct-fired coupling power generation system and method for conveying biomass by boiler smoke of coal-fired power station | |
| CN104913325A (en) | Combustion control method of boiler | |
| CN217154224U (en) | Direct-blowing pulverizing system with primary cooling fan and flue gas fan | |
| CN109268866B (en) | Medium speed pulverizer directly blows formula buggy combustion system suitable for high moisture coal type | |
| CN211316908U (en) | Drying equipment for drying biomass crude wet fuel by using boiler exhaust smoke waste heat | |
| CN107388263A (en) | A kind of sludge collaboration burning processing system and processing method | |
| CN106287679A (en) | A kind of pulverized-coal fired boiler high-temperature flue gas circulation controlling means |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |