CN109084319B - Flue gas recirculation system adopting two stages for heat exchange - Google Patents
Flue gas recirculation system adopting two stages for heat exchange Download PDFInfo
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- CN109084319B CN109084319B CN201810862497.6A CN201810862497A CN109084319B CN 109084319 B CN109084319 B CN 109084319B CN 201810862497 A CN201810862497 A CN 201810862497A CN 109084319 B CN109084319 B CN 109084319B
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- flue
- flue gas
- recirculation
- heat exchange
- fan
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- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 title claims abstract description 91
- 239000003546 flue gas Substances 0.000 title claims abstract description 91
- 239000000428 dust Substances 0.000 claims abstract description 18
- 239000007789 gas Substances 0.000 claims abstract description 6
- 238000007789 sealing Methods 0.000 claims description 13
- 238000000605 extraction Methods 0.000 claims description 7
- 241000270708 Testudinidae Species 0.000 claims description 4
- 239000000919 ceramic Substances 0.000 claims description 4
- 239000002131 composite material Substances 0.000 claims description 4
- 239000000779 smoke Substances 0.000 abstract description 15
- 238000004939 coking Methods 0.000 abstract description 2
- 230000002401 inhibitory effect Effects 0.000 abstract 1
- 238000004064 recycling Methods 0.000 description 17
- 239000002245 particle Substances 0.000 description 12
- 238000005299 abrasion Methods 0.000 description 10
- 230000000694 effects Effects 0.000 description 6
- 238000010438 heat treatment Methods 0.000 description 4
- 230000008602 contraction Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000003303 reheating Methods 0.000 description 3
- 230000000391 smoking effect Effects 0.000 description 3
- 238000003466 welding Methods 0.000 description 3
- 238000009825 accumulation Methods 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000003628 erosive effect Effects 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000003134 recirculating effect Effects 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 238000010977 unit operation Methods 0.000 description 1
Classifications
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- 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
- F23J15/06—Arrangements of devices for treating smoke or fumes of coolers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22D—PREHEATING, OR ACCUMULATING PREHEATED, FEED-WATER FOR STEAM GENERATION; FEED-WATER SUPPLY FOR STEAM GENERATION; CONTROLLING WATER LEVEL FOR STEAM GENERATION; AUXILIARY DEVICES FOR PROMOTING WATER CIRCULATION WITHIN STEAM BOILERS
- F22D1/00—Feed-water heaters, i.e. economisers or like preheaters
- F22D1/02—Feed-water heaters, i.e. economisers or like preheaters with water tubes arranged in the boiler furnace, fire tubes, or flue ways
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23B—METHODS OR APPARATUS FOR COMBUSTION USING ONLY SOLID FUEL
- F23B80/00—Combustion apparatus characterised by means creating a distinct flow path for flue gases or for non-combusted gases given off by the fuel
- F23B80/02—Combustion apparatus characterised by means creating a distinct flow path for flue gases or for non-combusted gases given off by the fuel by means for returning flue gases to the combustion chamber or to the combustion zone
-
- 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
- F23C9/08—Combustion apparatus characterised by arrangements for returning combustion products or flue gases to the combustion chamber for reducing temperature in combustion chamber, e.g. for protecting walls of combustion chamber
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES
- F23J13/00—Fittings for chimneys or flues
-
- 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
-
- 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
- F23L15/00—Heating of air supplied for combustion
- F23L15/04—Arrangements of recuperators
- F23L15/045—Arrangements of recuperators using intermediate heat-transfer fluids
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES
- F23J2217/00—Intercepting solids
- F23J2217/10—Intercepting solids by filters
- F23J2217/102—Intercepting solids by filters electrostatic
-
- 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)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
Abstract
The invention relates to a flue gas recirculation system adopting two stages for heat exchange, which is designed for effectively controlling the temperature level of a hearth and inhibiting or preventing the hearth from coking. The invention discloses a flue gas recirculation system for carrying out heat exchange by adopting two stages, which comprises a main flue connected to a flue gas outlet of a boiler, wherein a preheater, an electric dust collector and a draught fan are sequentially arranged on a flue gas main pipeline behind the electric dust collector, the recirculation flue is communicated with a boiler hearth, an adjusting baffle device is arranged on the recirculation flue between the recirculation fan and an air inlet of the boiler hearth, a flue gas bypass is arranged on the preheater, and a high-pressure economizer and a low-pressure economizer are arranged on the flue gas bypass for carrying out heat exchange to reduce the exhaust gas temperature. According to the invention, the combination of the baffle plate and the smoke recirculation is adopted to carry out reheat steam temperature regulation, so that the running stability and economy of the secondary reheat unit are improved.
Description
Technical Field
The invention particularly relates to a flue gas recirculation system adopting two stages for heat exchange.
Background
The difficulty of the secondary reheating boiler is that the adjustment of the temperatures of the main steam, the primary reheating steam and the secondary reheating steam is difficult, and the outlet temperatures of the three types of steam are complicated. The reheat steam temperature regulation mode is selected reasonably or not and is directly related to the reliability of unit operation, unit efficiency and the like, and even directly related to the safe operation of a power plant and a power grid, so that the temperature regulation mode and the reliability of the secondary reheat boiler are important to the design of the secondary reheat boiler.
Disclosure of Invention
In order to solve the technical problems, the invention aims to provide a flue gas recirculation system which reduces the temperature of discharged flue gas and improves the running economy of a unit and adopts two stages for heat exchange.
The invention adopts a two-stage heat exchange flue gas recirculation system, which comprises: the device is characterized in that a main flue is arranged at a boiler flue gas outlet, a preheater, an electric dust collector and an induced draft fan are sequentially arranged on a flue gas main pipeline, a recycling flue is communicated with the flue gas main pipeline after the electric dust collector, the recycling flue is communicated to a boiler furnace, an adjusting baffle device is arranged on the recycling flue between the recycling fan and an air inlet of the boiler furnace, a flue gas bypass is arranged on the preheater, and a high-pressure economizer and a low-pressure economizer are arranged on the flue gas bypass to perform two-stage heat exchange so as to reduce the exhaust gas temperature.
Further, the high-pressure economizer and the low-pressure economizer are arranged in series, the high-pressure economizer is arranged on the high-temperature flue gas side, the low-pressure economizer is arranged on the outlet section, the working media exchange heat in a countercurrent mode, and the high-pressure economizer and the low-pressure economizer both adopt H-shaped fin tubes.
Further, the recycling flue is communicated with the main flue through a flue extraction device, the flue extraction device is arranged at the top of the main flue in a wrapping mode, the upper portion of the recycling flue is a circular recycling flue, the middle portion of the recycling flue is a conical shrinkage section, the bottom of the conical shrinkage section is directly welded with the main flue, the width dimension of an opening of the main flue is equal to the diameter of a main flue pipe, a flue guide plate is arranged on the bottom plate of the main flue, and the welding direction of the guide plate is in an angle along the flue direction.
Further, the length of the guide plate is 300mm, the horizontal included angle of the guide plate direction is 60 degrees, and the guide plates are arranged at equal intervals of 300 mm.
Further, the recycling flue adopts a circular flue, and the flow rate of the flue gas in the recycling flue is 10 < -15 > m/s.
Further, wear-resistant ceramic plates or wear-resistant tortoise shell nets are attached to the inner walls of the recirculation flue area and the diversion elbow area of the outlet and inlet of the recirculation fan.
Further, a sealing baffle door is arranged at the inlet and the outlet of the recirculation fan, and sealing air is taken from the sealing fan or the air feeder.
Further, the access points of the recycling flue and the hearth are provided with fin openings or converging boxes for preventing the smoke from flowing backwards.
Further, 4 recirculation fans are arranged, and the flue gas respectively extracted by each recirculation fan is respectively sent to four corners of the lower part of the boiler furnace.
Further, the rotating speed of the recirculating fan is not more than 1000rpm, the impeller is integrally cast, and the upper part of the shell is additionally provided with the wear-resistant composite board.
By means of the scheme, the flue gas recirculation system adopting two stages for heat exchange has at least the following advantages:
the invention extracts flue gas from the back of the furnace and connects to the lower part of the furnace through the recirculation fan, in order to reduce the temperature of the boiler exhaust gas, the preheater is provided with a flue gas bypass, the high-pressure economizer and the low-pressure economizer are adopted to exchange heat to reduce the temperature of the exhaust gas, the heat release characteristic of the fuel is adjusted by doping low-temperature flue gas into the hearth, and the convection heat exchange is enhanced to realize the effective adjustment of the temperature of the reheat steam, thereby achieving the purpose of improving the running economy of the unit.
The foregoing description is only an overview of the present invention, and is intended to provide a better understanding of the present invention, as it is embodied in the following description, with reference to the preferred embodiments of the present invention and the accompanying drawings.
Drawings
FIG. 1 is a schematic diagram of a flue gas recirculation system employing two stages for heat exchange in accordance with the present invention;
FIG. 2 is a flow chart of the flue gas recirculation system of the present invention employing two stages for heat exchange;
FIG. 3 is a schematic diagram of a flue extraction device of a flue gas recirculation system employing two stages for heat exchange in accordance with the present invention;
fig. 4 is an E-direction view of fig. 3.
Detailed Description
The following describes in further detail the embodiments of the present invention with reference to the drawings and examples. The following examples are illustrative of the invention and are not intended to limit the scope of the invention.
Example 1
As shown in fig. 1 to 2, the present embodiment adopts a two-stage heat exchange flue gas recirculation system, including: comprising the following steps: the device is characterized in that a main flue is arranged at a boiler flue gas outlet, a preheater, an electric dust collector and an induced draft fan are sequentially arranged on a flue gas main pipeline, a recycling flue is communicated with the flue gas main pipeline after the electric dust collector, the recycling flue is communicated to a boiler furnace, an adjusting baffle device is arranged on the recycling flue between the recycling fan and an air inlet of the boiler furnace, a flue gas bypass is arranged on the preheater, and a high-pressure economizer and a low-pressure economizer are arranged on the flue gas bypass to perform two-stage heat exchange so as to reduce the exhaust gas temperature.
The high-pressure economizer and the low-pressure economizer are connected in series for arrangement, the high-pressure economizer is arranged on the high-temperature flue gas side, the low-pressure economizer is arranged on the outlet section, the working media exchange heat in a countercurrent mode, and the high-pressure economizer and the low-pressure economizer both adopt H-shaped fin tubes.
According to the embodiment, the input of the flue gas recirculation system can influence the change of the temperature of the flue gas at the bottom of the screen, so that the temperature level of the hearth can be effectively controlled, and the hearth is inhibited or prevented from coking; by adopting the proper smoke recirculation share, the temperature level of the screen bottom smoke is reduced along with the increase of the recirculation smoke share, so that the radiant heat absorption capacity of the hearth and the residence time of the smoke in the hearth are reduced, and the radiant heating surface arranged at the upper part of the hearth is slightly reduced due to the temperature of the smoke, so that the overtemperature phenomenon of the superheater heating surface at the upper part of the hearth can not be caused. And the temperature of the flue gas at the outlet of the hearth is not increased. As the flow of the flue gas at the convection heating surface is increased, the heat release coefficient at the flue gas side is increased, the convection heat transfer capacity is increased, the temperature of the working medium outlet is increased, and the change degree of the heating surface positioned at the downstream of the flue gas travel is more obvious. Generally, when the recycling flue gas rate is 20% -25%, the steam temperature of the high-pressure reheater and the low-pressure reheater can be increased by 30-40 ℃.
Example 2
As shown in fig. 3 to 4, the two-stage flue gas recirculation system for heat exchange is adopted in this embodiment, on the basis of embodiment 1, the recirculation flue is communicated with the main flue through a flue extraction device, the flue extraction device is wrapped and arranged at the top of the main flue, the upper part is a circular recirculation flue, the middle part is a conical contraction section, the bottom of the conical contraction section is directly welded with the main flue, the width dimension of the opening of the main flue is equal to the diameter of the main flue, the bottom plate of the main flue is provided with a flue gas guide plate, and the welding direction of the guide plate is in an angle along the flue gas direction.
In this embodiment, through the setting of smoking mouth guide plate, utilize self gravity and the velocity difference of dust in the flue gas to produce natural separation flue gas extraction device and arrange in denitration main flue top, upper portion is circular smoking main pipe, and the pipe diameter size selects suitable flue gas velocity of flow according to the smoking flow and selects, and the design of circular flue not only can further reduce flue wearing and tearing, can also reduce flue resistance. The middle part of the device is a conical contraction section, the effect of local medium-high smoke flow velocity is generated, the effect of dust carrying of smoke is increased, and the effect of preventing dust accumulation of the smoke exhausting device is achieved. The bottom of the device is directly welded with the main flue, the width dimension of the opening of the main flue is equal to the diameter of the main flue, the length dimension is calculated and determined according to the selected flue gas flow velocity, the bottom plate of the flue gas suction port is welded with a flue gas guide plate, the welding direction of the guide plate forms an angle along the flue gas direction, and the angle, the interval and the specification of the guide plate can be determined through the simulation result of the flue gas flow field. The simulation result of the distribution of the particles in the flue gas flow field shows that due to the arrangement of the guide plate, the velocity difference of the smoke particles is generated near the section of the guide plate, the particles with small particle size and the particles with larger particle size are naturally separated by gravity, and most of the smoke particles are still carried away by the flue gas from the main flue, so that a better separation effect can be achieved. In this embodiment, the size of the baffle structure is as follows: the length of the guide plate is 300mm, the horizontal included angle of the guide plate direction is 60 degrees, and the guide plates are arranged at equal intervals of 300 mm.
Example 3
In the embodiment, a two-stage heat exchange flue gas recirculation system is adopted, and on the basis of embodiment 1, the recirculation flue adopts a circular flue, and the flow rate of flue gas in the recirculation flue is 10-15m/s. And wear-resistant ceramic plates or wear-resistant tortoise shell nets are adhered to the inner walls of the recirculation flue area and the diversion elbow area of the outlet and inlet of the recirculation fan.
In this embodiment, the flow rate of the flue is typically 10-15m/s, and too high a flow rate will accelerate the abrasion of the flue, but the flow rate of the flue gas cannot be too low, otherwise, the dust accumulation in the bend turning area will be caused. The adoption of the circular flue can avoid the design and use of the inner supporting rod of the flue, so that the erosion and abrasion of the inner supporting rod of the flue can be avoided, and the flue resistance can be further reduced. And adopting wear-resistant measures such as sticking wear-resistant ceramic plates or wear-resistant tortoise shell nets and the like in the flue areas of the outlet and inlet of the fan and the turning elbow areas. The adoption of the measures of the embodiment can greatly avoid the occurrence of the abrasion condition of the flue.
Example 4
In the embodiment, a two-stage heat exchange flue gas recirculation system is adopted, and on the basis of embodiment 1, a sealing baffle door is arranged at an inlet and an outlet of the recirculation fan, and sealing air is taken from a sealing fan or a blower.
In this embodiment, during the operation of the secondary boiler, when the flue gas recirculation fan is stopped, the flue gas may flow in reverse. In order to prevent the occurrence of the situation, the inlet and outlet of the smoke recirculation fan can be provided with a sealing baffle door by referring to similar engineering experiences at home and abroad, and sealing air is taken from a special sealing fan or a blower, so that the sealing effect of the baffle is ensured.
Example 5
In this embodiment, a two-stage flue gas recirculation system for heat exchange is adopted, and on the basis of embodiment 1, the access points of the recirculation flue and the furnace chamber are provided with fin openings or a converging header for preventing flue gas from flowing backwards.
In the aspect of preventing burning loss, the access point of the recycling flue and the hearth can adopt measures such as fin holes, converging boxes and the like to ensure that the flue cannot be burned out due to backflow of flue gas. In addition, the recirculated flue gas generally accounts for about 10-20% of the total flue gas, and is disposed at a position remote from the burner so as not to affect combustion and therefore slag removal.
Example 6
In the embodiment, a two-stage heat exchange flue gas recirculation system is adopted, on the basis of the embodiment 1, the rotating speed of the recirculation fan is not more than 1000rpm, the impeller is integrally cast, and the wear-resistant composite plate is additionally arranged on the upper part of the shell.
The through-flow medium of the smoke recirculation fan is a high-temperature high-dust-content medium, and the abrasion mechanism is material erosion abrasion caused by impact of dust on the wall surface under the action of air flow entrainment and self inertia. In the outlet area of the centrifugal flow channel, dust particles move a long distance in the flow channel, most of the dust particles collide with the wall surface for many times, basically slide or roll along the pressure surface and have a certain pressure effect on the wall surface, so that the abrasion of the back surface material caused by the abrasion belongs to abrasion type dust particle abrasion, and the damage degree of the dust particle abrasion is further increased by the concentration of the dust particles in the area near the pressure surface.
In this embodiment, the smoke recirculation fan adopts the following combined anti-wear technical measures:
and a low-rotation-speed fan is adopted, and the rotation speed of the fan is not more than 1000rpm.
The novel wear-resistant alloy is adopted to cast the impeller and the shell, the impeller is integrally cast, and the wear-resistant composite board is additionally arranged on the upper part of the shell.
The surface of the impeller adopts a novel surfacing wear-resistant Fe-05 material.
And a new technology (such as ternary flow) of fan flow field design is adopted, so that the fan flow field is further optimized, and the overall wear resistance is improved.
After the wear-resistant technical measures are adopted, the continuous operation period of the fan can reach more than 2 years, and the maintenance and operation requirements of the thermal power plant are completely met.
Example 7
In the embodiment, a two-stage flue gas recirculation system for heat exchange is adopted, 4 recirculation fans are arranged on the basis of embodiment 1, and flue gas respectively extracted by each recirculation fan is respectively sent to four corners of the lower part of a boiler hearth. The recirculated flue gas directly enters the flue gas recirculation fan and then is sent to four corners of the lower part of the boiler furnace. In order to increase the flexibility of flue gas adjustment, the safety source engineering is provided with 4 centrifugal furnace flue gas fans with 30% capacity, and variable frequency control is adopted.
The above description is only of the preferred embodiments of the present invention and is not intended to limit the present invention, and it should be noted that it is possible for those skilled in the art to make several improvements and modifications without departing from the technical principle of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.
Claims (8)
1. A flue gas recirculation system for heat exchange using two stages, comprising: the device comprises a boiler flue gas outlet, a main flue, a preheater, an electric dust collector and an induced draft fan are sequentially arranged on the main flue, a recirculation flue is communicated on the main flue after the electric dust collector, the recirculation flue is communicated to a boiler furnace, a recirculation fan is arranged on the recirculation flue, an adjusting baffle device is arranged on the recirculation flue between the recirculation fan and an air inlet of the boiler furnace, a flue gas bypass is arranged on the preheater, a high-pressure economizer and a low-pressure economizer are arranged on the flue gas bypass for two-stage heat exchange to reduce the exhaust gas temperature, the high-pressure economizer and the low-pressure economizer are arranged in series, the high-pressure economizer is arranged on the high-temperature flue gas side, the low-pressure economizer is arranged on the outlet section, working mediums are all subjected to countercurrent heat exchange, the high-pressure economizer and the low-pressure flue economizer are all in H-shaped fin pipes, the recirculation flue is communicated with the main flue through a flue extraction device, the upper part is arranged at the top of the main flue, the middle part is a circular recirculation flue, the middle part is a conical shrinkage section, the bottom of the conical section is directly shrunk with the main flue gas, the main flue gas is directly welded with the main flue gas, the diameter is directly, and a flow guide plate is arranged in the direction of the main flue gas is welded, and the direction of the flow guide plate is provided with the flow guide plate.
2. The flue gas recirculation system for heat exchange by two stages according to claim 1, wherein the length of the deflector is 300mm, the horizontal included angle of the direction of the deflector is 60 °, and the deflector is arranged at equal intervals of 300 mm.
3. The flue gas recirculation system for two-stage heat exchange according to claim 1, wherein the recirculation flue is a circular flue, and the flow rate of flue gas in the recirculation flue is 10-15m/s.
4. The flue gas recirculation system employing two stages for heat exchange according to claim 1, wherein wear resistant ceramic plates or wear resistant tortoise shell mesh are attached to the inner walls of the recirculation flue region and the redirecting elbow region at the outlet and inlet of the recirculation fan.
5. The flue gas recirculation system employing two stages for heat exchange according to claim 1, wherein a sealing damper door is provided at an inlet and an outlet of the recirculation fan, and sealing air is taken from the sealing fan or the blower.
6. The flue gas recirculation system for two-stage heat exchange according to claim 1, wherein the access point of the recirculation flue and the furnace is provided with a fin opening or a converging header for preventing the backflow of flue gas.
7. The flue gas recirculation system for heat exchange by two stages according to claim 1, wherein 4 recirculation fans are provided, and flue gas respectively extracted by each recirculation fan is respectively sent to four corners of the lower part of the boiler furnace.
8. The flue gas recirculation system for heat exchange by two stages according to claim 1, wherein the rotation speed of the recirculation fan is not more than 1000rpm, the impeller is integrally cast, and the wear-resistant composite plate is additionally arranged on the upper part of the casing.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810862497.6A CN109084319B (en) | 2018-08-01 | 2018-08-01 | Flue gas recirculation system adopting two stages for heat exchange |
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| CN201810862497.6A CN109084319B (en) | 2018-08-01 | 2018-08-01 | Flue gas recirculation system adopting two stages for heat exchange |
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| CN109084319B true CN109084319B (en) | 2023-12-19 |
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| CN110107882A (en) * | 2019-05-31 | 2019-08-09 | 德润鑫鼎(北京)工程技术有限公司 | A kind of steam waste-heat recovery device for boiler combustion system |
| CN112138513B (en) * | 2020-10-26 | 2024-08-02 | 河北建投能源科学技术研究院有限公司 | Device capable of dynamically adjusting membrane method water yield and adjusting and controlling method |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203431902U (en) * | 2013-06-28 | 2014-02-12 | 江西省电力设计院 | Smoke system reducing exhaust smoke temperature of secondary reheating boiler |
| CN103776015A (en) * | 2014-02-26 | 2014-05-07 | 章礼道 | Semi-tower three-flue double-damper added jet flow flue gas recirculation secondary reheating power station boiler |
| WO2014079247A1 (en) * | 2012-11-20 | 2014-05-30 | 上海锅炉厂有限公司 | Power station boiler economizer |
| CN203718759U (en) * | 2014-01-27 | 2014-07-16 | 东方电气集团东方锅炉股份有限公司 | Circulating fluidized bedboiler fueling alkali-containing metal element fuels |
| CN104501140A (en) * | 2014-11-28 | 2015-04-08 | 哈尔滨锅炉厂有限责任公司 | Medium-temperature smoke re-circulating system for regulating steam temperature and circulating method |
| CN206469251U (en) * | 2016-09-29 | 2017-09-05 | 国电科学技术研究院 | A kind of high temperature neat stress recirculating system |
| CN208967826U (en) * | 2018-08-01 | 2019-06-11 | 中国电建集团江西省电力设计院有限公司 | The flue gas recirculation system to be exchanged heat using two-stage |
-
2018
- 2018-08-01 CN CN201810862497.6A patent/CN109084319B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2014079247A1 (en) * | 2012-11-20 | 2014-05-30 | 上海锅炉厂有限公司 | Power station boiler economizer |
| CN203431902U (en) * | 2013-06-28 | 2014-02-12 | 江西省电力设计院 | Smoke system reducing exhaust smoke temperature of secondary reheating boiler |
| CN203718759U (en) * | 2014-01-27 | 2014-07-16 | 东方电气集团东方锅炉股份有限公司 | Circulating fluidized bedboiler fueling alkali-containing metal element fuels |
| CN103776015A (en) * | 2014-02-26 | 2014-05-07 | 章礼道 | Semi-tower three-flue double-damper added jet flow flue gas recirculation secondary reheating power station boiler |
| CN104501140A (en) * | 2014-11-28 | 2015-04-08 | 哈尔滨锅炉厂有限责任公司 | Medium-temperature smoke re-circulating system for regulating steam temperature and circulating method |
| CN206469251U (en) * | 2016-09-29 | 2017-09-05 | 国电科学技术研究院 | A kind of high temperature neat stress recirculating system |
| CN208967826U (en) * | 2018-08-01 | 2019-06-11 | 中国电建集团江西省电力设计院有限公司 | The flue gas recirculation system to be exchanged heat using two-stage |
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