CN215372398U

CN215372398U - Steam boiler

Info

Publication number: CN215372398U
Application number: CN202121698023.6U
Authority: CN
Inventors: 曹益民
Original assignee: Deqing Lvneng Thermal Power Co ltd
Current assignee: Deqing Lvneng Thermal Power Co ltd
Priority date: 2021-07-24
Filing date: 2021-07-24
Publication date: 2021-12-31
Anticipated expiration: 2031-07-24

Abstract

The application relates to a steam boiler, and relates to the technical field of boiler equipment. When the steam boiler starts to operate, the temperature distribution in the hearth is uneven, so that the combustion condition in the hearth is easy to deteriorate. This application includes furnace, the chimney and the steam pocket that link to each other with furnace, and furnace includes the combustion section, connects in the waste heat section of combustion section, and the combustion section is equipped with first fuel nozzle, first conveyer pipe and secondary air pipe, and the secondary air pipe stretches into in the furnace and towards the waste heat section, is connected with primary air pipe on the first defeated powder pipe. The primary air pipe conveys primary air into the first powder conveying pipe, the pulverized coal and the primary air are mixed, the first burner ignites and sprays the pulverized coal, the secondary air pipe conveys secondary air towards the waste heat section, the secondary air promotes the pulverized coal to be fully combusted, and the secondary air can blow flue gas generated by the combustion of the pulverized coal to the waste heat section, so that the temperature inside the hearth is promoted to be rapid and uniform.

Description

Steam boiler

Technical Field

The present application relates to the field of boiler plants, in particular to a steam boiler.

Background

The steam boiler is an industrial boiler which heats water to certain parameters and produces high-temperature steam, and is mainly used for thermal power stations, ships, locomotives and industrial and mining enterprises.

Steam boilers generally comprise a furnace and a steam drum filled with water, the steam drum conveys water to the outer wall of the furnace, pulverized coal is combusted in the furnace to generate heat, and the water is heated to become water vapor. The pulverized coal is ignited by a burner at one end of the hearth, and the flue gas moves to the other end along the hearth and then is discharged from a chimney.

In view of the above-mentioned related technologies, the inventor believes that the steam boiler has uneven temperature distribution in the furnace and large temperature difference between two ends of the furnace during a period of time when the steam boiler starts to operate, which causes deterioration of combustion in the furnace, and the pulverized coal is not sufficiently combusted at a low temperature of the furnace along with diffusion and movement of flue gas, so that the combustion efficiency of the pulverized coal is low.

SUMMERY OF THE UTILITY MODEL

In order to promote even temperature distribution in the hearth and coal dust to fully combust in the hearth, the application provides a steam boiler.

The application provides a steam boiler adopts following technical scheme:

the utility model provides a steam boiler, includes furnace, steam pocket, chimney, furnace include the combustion section and communicate in the waste heat section of combustion section, the tip of waste heat section communicate in the chimney, the combustion section be equipped with first burner, be used for carrying the first defeated powder pipe and the secondary air pipe of buggy, install defeated powder fan on the first defeated powder pipe, the intercommunication has a tuber pipe on the first defeated powder pipe, the output of a tuber pipe communicate in first defeated powder pipe, the output of first burner stretches into in the combustion section, first defeated powder union coupling in the input of first burner, the output of secondary air pipe stretches into in the combustion section, and the orientation the waste heat section.

Through adopting above-mentioned technical scheme, because the secondary air pipe sets up towards furnace's waste heat section, secondary air pipe exhaust overgrate air is when promoting buggy burning, still blows the high temperature flue gas that the burning produced to the waste heat section, makes the high temperature flue gas be full of whole furnace rapidly for the inside temperature short time of furnace distributes evenly, is favorable to making the abundant burning of buggy, improves the combustion efficiency of buggy.

Optionally, the waste heat section is provided with a second burner and a second powder conveying pipe for conveying pulverized coal, an output end of the second burner extends into the waste heat section, and the second powder conveying pipe is communicated with an input end of the second burner.

By adopting the technical scheme, the second powder conveying pipe conveys the pulverized coal to the inside of the second burner, and the second burner ignites and sprays the pulverized coal, so that the temperature difference between the combustion section and the waste heat section can be reduced, and the temperature inside the hearth is further uniformly distributed in a short time.

Optionally, the secondary air pipe is provided with at least two, and all face towards the waste heat section.

Through adopting above-mentioned technical scheme, many secondary air pipes can improve the input of overgrate air, make buggy fully burn, also can blow more hot ripples to the waste heat section simultaneously for the temperature in the furnace is quick even.

Optionally, the primary air pipe penetrates through the waste heat section.

Through adopting above-mentioned technical scheme, the primary air pipe runs through the waste heat section, then can preheat the primary air pipe through the flue gas of waste heat section for exhaust primary air temperature is higher, and the air mixes the back with the buggy, and the buggy is lighted by first jet burner more easily, thereby improves the combustion efficiency of buggy, makes the buggy fully burn.

Optionally, the secondary air pipe penetrates through the waste heat section.

Through adopting above-mentioned technical scheme, the flue gas of waste heat section can preheat the secondary air pipe for the temperature of overgrate air rises, and the back is lighted to the buggy, and the overgrate air lets in the furnace and makes the buggy can last, abundant burning, and the overgrate air temperature is higher then the buggy burning is more abundant.

Optionally, a coal ash filter screen is arranged at the end part of the secondary air pipe extending into the hearth.

Through adopting above-mentioned technical scheme, the buggy that lets in the furnace probably has a small amount of great granule of volume, and the coal ash filter screen can reduce the buggy and fall into in the secondary tuber pipe, avoids the buggy to fall into the condition that leads to secondary tuber pipe jam in the secondary tuber pipe as far as possible for the intake of secondary tuber pipe is sufficient.

Optionally, the coal ash screen is detachably connected to the secondary air pipe.

Through adopting above-mentioned technical scheme, after long-time the use, probably some buggy granule jam on the coal ash filter screen, the setting can be dismantled to the coal ash filter screen, and the staff of being convenient for tears the coal ash filter screen out and clears up.

Optionally, the first burners are provided with a plurality of burners, and the first burners are arranged at intervals along the circumferential direction of the furnace.

By adopting the technical scheme, the plurality of jet burners can ignite the pulverized coal from a plurality of directions, so that the pulverized coal is fully combusted, and the combustion efficiency of the pulverized coal is improved.

In summary, the present application includes at least one of the following beneficial technical effects:

1. because the secondary air pipe faces the waste heat section, high-temperature flue gas generated by combustion can rapidly move to the waste heat section, the temperature in the hearth is uniformly distributed in a short time, and the full combustion of pulverized coal is facilitated;

2. through setting up second fuel nozzle and second defeated powder pipe, the buggy burns at the waste heat section to reduce the temperature difference of burning section and waste heat section, further impel the inside temperature of furnace to distribute evenly in the short time.

Drawings

FIG. 1 is a schematic structural diagram of a steam boiler according to an embodiment of the present disclosure;

FIG. 2 is a schematic structural view of the steam drum and the hearth in FIG. 1 after being cut;

fig. 3 is an enlarged schematic view at a in fig. 2.

Description of reference numerals: 1. a hearth; 11. a combustion section; 111. a first burner; 112. a first powder conveying pipe; 113. a primary air duct; 114. a secondary air duct; 115. a powder conveying fan; 116. a coal ash screen; 12. a waste heat section; 121. a second burner; 122. a second powder conveying pipe; 13. a combustion chamber; 2. a steam drum; 21. a vapor-water storage chamber; 22. an evaporator; 23. a superheater; 24. a coal economizer; 25. a steam-water separator; 3. a chimney; 31. an induced draft fan; 5. a cold ash hopper.

Detailed Description

The present application is described in further detail below with reference to figures 1-3.

The embodiment of the application discloses a steam boiler.

Referring to fig. 1 and 2, a steam boiler includes a furnace 1, a drum 2, and a stack 3, the furnace 1 is substantially inverted U-shaped as a whole, and a combustion chamber 13 having a circular cross-section is provided inside the furnace 1. The furnace 1 is divided into two sections with the same length along the length direction of the furnace 1, and the furnace 1 comprises a combustion section 11 and a waste heat section 12. Four first burners 111 are fixedly mounted on the outer wall of the combustion section 11, the first burners 111 are arranged at equal intervals along the circumferential direction of the combustion chamber 13, and the output ends of the first burners 111 extend into the combustion chamber 13. The combustion section 11 is further provided with a first powder conveying pipe 112, a primary air pipe 113 and a secondary air pipe 114, wherein the output end of the primary air pipe 113 is communicated with the first powder conveying pipe 112, and the output end of the secondary air pipe 114 extends into the combustion chamber 13. The first powder conveying pipe 112 is used for conveying pulverized coal to the four first burners 111, a powder conveying fan 115 is installed on the first powder conveying pipe 112, and the output end of the secondary air pipe 114 is arranged along the length direction of the hearth 1 and points to the waste heat section 12. The end of the waste heat section 12 is connected to the chimney 3, and an induced draft fan 31 is installed between the waste heat section 12 and the chimney 3.

The primary air pipe 113 leads primary air into the first powder conveying pipe 112, the primary air and the pulverized coal are mixed into a whole, then under the action of the powder conveying fan 115, the primary air carries the pulverized coal into the four first burners 111, and the first burners 111 ignite and spray the pulverized coal outwards; meanwhile, the secondary air pipe 114 continuously introduces secondary air into the combustion chamber 13, which plays a role of supplying oxygen, promotes the pulverized coal to be fully combusted, and improves the combustion efficiency of the pulverized coal. Because the secondary air pipe 114 faces the waste heat section 12, when the pulverized coal is combusted to generate smoke, the subsequently introduced secondary air blows the smoke and the heat waves to the waste heat section 12, so that the high-temperature smoke can fill the combustion chamber 13 in a short time, and the temperature in the combustion chamber 13 is promoted to be uniformly distributed in a short time. Under the action of induced air of the induced draft fan 31, the flue gas is introduced into the chimney 3 and discharged.

Referring to fig. 2 and 3, the end of the combustion section 11 is open, and the lower end of the combustion section 11 is provided with a cold ash hopper 5 for storing coal ash. The number of the secondary air pipes 114 is four, the output ends of the four secondary air pipes 114 are arranged along the circumferential direction of the combustion chamber 13, and the output ends of the secondary air pipes 114 face the waste heat section 12. The four secondary air pipes 114 correspond to the four first burners 111 one by one, and the first burners 111 are located above the output ends of the secondary air pipes 114. The output end of the secondary air pipe 114 is movably inserted with a round soot filter 116, so as to prevent soot particles with large volume from falling into the secondary air pipe 114 as much as possible, and facilitate workers to detach and clean the soot filter 116 independently.

The steam drum 2 is higher than the hearth 1, a steam-water storage chamber 21 for storing water and steam is arranged in the steam drum 2, the steam drum 2 is connected with an evaporator 22, a superheater 23 and an economizer 24, and the evaporator 22, the superheater 23 and the economizer 24 are pipelines. The evaporator 22 is spirally wound on the outer wall of the combustion section 11, both ends of the evaporator 22 are communicated with the steam-water storage chamber 21, and the output end of the evaporator 22 is connected with a common steam-water separator 25. The input end of the superheater 23 is communicated with the steam-water storage chamber 21, and the output end of the superheater 23 extends into the combustion chamber 13 of the combustion section 11, extends out of the combustion chamber 13 and is finally connected to a steam turbine (not shown in the figure). The input end of the coal economizer 24 is connected with a water source, and the output end of the coal economizer 24 extends into the combustion chamber 13 of the waste heat section 12, extends out of the combustion chamber 13 and is finally communicated with the steam-water storage chamber 21.

The economizer 24 conveys water from a water source to the steam pocket 2, and when the flue gas in the hearth 1 passes through the waste heat section 12, the flue gas exchanges heat with the economizer 24, so that the water temperature in the economizer 24 is increased, and the water preheating process is completed. The preheated water flows along the evaporator 22, the evaporator 22 exchanges heat with the hearth 1, the water temperature at the output end of the evaporator 22 is higher than that at the input end, the density of the steam-water mixture at the output end of the evaporator 22 is smaller than that at the input end, so that pressure difference is formed in the evaporator 22, the steam-water mixture is pushed into the steam pocket 2, and the water in the steam pocket 2 is pressed into the evaporator 22 to form natural circulation. The steam-water mixture is divided into saturated steam and water by a steam-water separator 25, the water continuously enters an evaporator 22 for heating, the saturated steam is introduced into a superheater 23 for heating to form superheated steam, and the superheated steam is used for driving a steam turbine (not shown in the figure) to operate.

A second burner 121 and a second powder conveying pipe 122 are arranged at a position of the waste heat section 12 close to the combustion section 11, the second burner 121 is fixedly installed on the outer wall of the waste heat section 12, an output end of the second burner 121 extends into the combustion chamber 13, and an output end of the second powder conveying pipe 122 is communicated with an input end of the second burner 121. A primary air pipe 113 is communicated with the pipe body of the second powder conveying pipe 122, a powder conveying fan 115 is arranged on the second powder conveying pipe 122, and the powder conveying fan 115 is positioned between the primary air pipe 113 and the second burner 121.

When the steam boiler is operated, the second burner 121 and the first burner 111 are operated at the same time, so that the waste heat section 12 has a higher temperature when the steam boiler is operated, thereby reducing the temperature difference between the combustion section 11 and the waste heat section 12 and promoting the uniform temperature distribution in the whole furnace 1 in a short time. When the steam boiler is operated for a period of time and the temperature in the furnace 1 is relatively uniform, the second burner 121 and the second powder conveying pipe 122 stop operating. Because the temperature distribution of the hearth 1 is not uniform at first, the pulverized coal diffuses to the waste heat section 12 along with the flue gas in the combustion process, the pulverized coal may extinguish when diffusing to the low-temperature part, and the second burner 121 is favorable for promoting the pulverized coal to be combusted again, so that the combustion efficiency of the pulverized coal is improved.

The implementation principle of the embodiment is as follows: because the secondary air pipe 114 faces the waste heat section 12, high-temperature flue gas generated by combustion can rapidly move to the waste heat section 12, the temperature in the hearth 1 is uniformly distributed in a short time, and the full combustion of pulverized coal is facilitated; by arranging the second burner 121 and the second powder conveying pipe 122, the pulverized coal is combusted in the waste heat section 12, so that the temperature difference between the combustion section 11 and the waste heat section 12 is reduced, and the temperature inside the hearth 1 is further promoted to be uniformly distributed in a short time.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. A steam boiler, characterized in that: including furnace (1), steam pocket (2), chimney (3), furnace (1) including combustion section (11) and communicate in waste heat section (12) of combustion section (11), the tip of waste heat section (12) communicate in chimney (3), combustion section (11) are equipped with first burner (111), are used for carrying the first defeated powder pipe (112) and secondary air pipe (114) of buggy, install defeated powder fan (115) on first defeated powder pipe (112), the intercommunication has primary air pipe (113) on first defeated powder pipe (112), the output of primary air pipe (113) communicate in first defeated powder pipe (112), the output of first burner (111) stretches into in combustion section (11), first defeated powder pipe (112) connect in the input of first burner (111), the output of secondary air pipe (114) stretches into in combustion section (11), and towards the waste heat section (12).

2. A steam boiler according to claim 1, characterized in that: the waste heat section (12) is provided with a second burner (121) and a second powder conveying pipe (122) for conveying pulverized coal, the output end of the second burner (121) extends into the waste heat section (12), and the second powder conveying pipe (122) is communicated with the input end of the second burner (121).

3. A steam boiler according to claim 1, characterized in that: the secondary air pipe (114) is provided with at least two air pipes which face the waste heat section (12).

4. A steam boiler according to claim 1, characterized in that: the primary air pipe (113) penetrates through the waste heat section (12).

5. A steam boiler according to claim 1, characterized in that: the secondary air pipe (114) penetrates through the waste heat section (12).

6. A steam boiler according to claim 1, characterized in that: and a coal ash filter screen (116) is arranged at the end part of the secondary air pipe (114) extending into the hearth (1).

7. A steam boiler according to claim 6, characterized in that: the coal ash screen (116) is detachably connected to the secondary air pipe (114).

8. A steam boiler according to claim 1, characterized in that: the number of the first burners (111) is multiple, and the first burners (111) are arranged at intervals along the circumferential direction of the hearth (1).