CN214223084U

CN214223084U - Circulating fluidized bed boiler capable of quickly adjusting circulating ash amount

Info

Publication number: CN214223084U
Application number: CN202023308972.7U
Authority: CN
Inventors: 胡南; 刁友锋; 宋珺琤; 刘恒; 王进博; 刘璐
Original assignee: Tianjin Development Branch Of Huadian International Power Co ltd
Current assignee: Tianjin Development Branch Of Huadian International Power Co ltd
Priority date: 2020-12-31
Filing date: 2020-12-31
Publication date: 2021-09-17
Anticipated expiration: 2030-12-31

Abstract

The utility model relates to a circulating fluidized bed boiler capable of quickly adjusting circulating ash amount, belonging to the technical field of heat supply and power station boilers, comprising a hearth, a separator, a return material valve, an air distribution plate and an air chamber, wherein one or more material adjusting storage bins are arranged outside the hearth; the material adjusting storage bin is connected with a blowing device and used for providing return air. The upper part of the material adjusting storage bin is connected with the hearth through a feeding pipe, and a feeding door is arranged on the feeding pipe. And a flue gas pipeline is arranged at the upper part of the material adjusting storage bin, and a flue gas door is arranged on the flue gas pipeline. And a material returning pipe is arranged at the lower part of the material adjusting storage bin, a material returning door is arranged on the material returning pipe, and the material returning pipe is connected to the bottom of the hearth. The utility model discloses a furnace puts the thing material outward and adjusts the storage storehouse and realize reducing the particle concentration smugglied secretly in the flue gas rapidly in the boiler load reduction in-process for the heat transfer coefficient of convection heating surface reduces rapidly, thereby reduces steam temperature fast, realizes the quick adjustment boiler load.

Description

Circulating fluidized bed boiler capable of quickly adjusting circulating ash amount

Technical Field

The utility model belongs to the technical field of heat supply and power plant boiler, in particular to circulating fluidized bed boiler of quick adjustment circulation ash volume.

Background

The circulating fluidized bed boiler blows fuels such as coal particles, biomass and bed materials from the bottom of a hearth through primary air with high pressure, so that the particles are in a fluidized state and are combusted. Bed materials in the hearth have strong heat storage capacity, and the residence time of the fuel in the hearth is prolonged through the separator, so that the circulating fluidized bed boiler has the characteristic of wide fuel application range; the circulating fluidized bed boiler can stably operate at a lower combustion temperature, and the generation of nitrogen oxides is much lower than that of a pulverized coal boiler; by adding limestone in the hearth, sulfur dioxide can be removed in the combustion process, and the desulfurization cost is greatly reduced. Based on the advantages, the circulating fluidized bed boiler is the best choice for large-scale clean utilization of fuels such as high-sulfur and high-ash coal, gangue, washed coal, coal slime, biomass and the like. In recent years, circulating fluidized bed boilers have been increasing in size and high in parameter.

With the fact that the proportion of new energy power generation to the total power generation is higher and higher, the thermal power generating unit is required to have a faster load adjustment rate and a larger load adjustment range. In the circulating fluidized boiler, the steam temperature is directly influenced by the temperature of the flue gas and the concentration of particles carried in the flue gas, the higher the flue gas temperature is, the higher the concentration of the carried particles is, the larger the heat exchange coefficient is, and the higher the steam temperature is.

The higher the flue gas temperature of the circulating fluidized boiler and the higher the concentration of entrained particles, the larger the heat exchange coefficient and the higher the steam temperature. A large amount of bed materials are arranged in a hearth of the circulating fluidized bed boiler, the temperature in the hearth is stable and uniform, the thermal inertia of the hearth is large due to the heat storage capacity of particles, and the particle circulation amount is difficult to change in the change conforming process, so that the temperature of the hearth changes slowly in the load adjusting process, and the load adjusting speed of the circulating fluidized bed boiler is obviously lower than that of a pulverized coal boiler of the same grade.

Disclosure of Invention

The utility model discloses a solve the technical problem that exists among the above-mentioned prior art, provide a circulating fluidized bed boiler of quick adjustment circulation ash volume, can promote the speed that boiler load goes up and down by a wide margin, improve the unit flexibility.

The utility model comprises the following technical scheme:

a circulating fluidized bed boiler capable of quickly adjusting circulating ash amount comprises a hearth, a separator, a material return valve, an air distribution plate and an air chamber, wherein one or more material adjusting storage bins are arranged outside the hearth; the material adjusting storage bin is connected with a blowing device and used for providing return air.

Furthermore, the upper part of the material adjusting storage bin is connected with the hearth through a feeding pipe, and a feeding door is arranged on the feeding pipe.

Furthermore, a flue gas pipeline is arranged at the upper part of the material adjusting storage bin, and a flue gas door is arranged on the flue gas pipeline. The flue gas pipeline is connected to a tail flue at the top of the separator.

Furthermore, a material returning pipe is arranged at the lower part of the material adjusting storage bin, and a material returning door is arranged on the material returning pipe and connected to the bottom of the hearth.

Furthermore, an air chamber is arranged at the bottom of the hearth, and the air distribution plate is arranged at the top of the air chamber.

Furthermore, the upper part of the separator is connected with the upper part of the hearth, the lower part of the separator is connected with a material returning valve, and the material returning valve is connected with the lower part of the hearth.

The utility model discloses a theory of operation:

in the full-load working condition operation process of the circulating fluidized bed boiler, primary air enters an air chamber and enters a hearth through an air distribution plate, bed materials and fuel in the hearth are fluidized, part of fine particles are brought out of the hearth by fluidized air and enter a separator, most of the particles are captured by the separator and return to the hearth through a material return valve, and a small part of ultrafine particles escape from the separator along with flue gas. At the moment, the feeding door, the smoke gas door and the material returning door of the material adjusting storage bin are all in a closed state.

When the circulating fluidized bed boiler needs to rapidly reduce the load, the feeding door and the flue gas door are opened, and because the material adjusting storage bin is connected with the outlet flue of the separator, the pressure is low, circulating ash can continuously enter the material adjusting storage bin, so that the circulating ash in the hearth is rapidly reduced. Because the materials in the hearth are reduced, the heat transfer coefficient of the hearth is reduced, the temperature of the hearth is reduced, and the output of the boiler is rapidly reduced. The bed materials are stored in the material adjusting storage bin and keep the original temperature.

When the boiler needs to lift load, the feeding door and the flue gas door are closed, the return door is opened, and return air is provided, so that bed materials in the material adjusting storage bin are fluidized, and the bed materials return to the hearth through the return pipe. Because the bed material is still in a high-temperature state, the temperature in the hearth is improved, and the speed of increasing the load of the boiler is increased.

The utility model has the advantages and positive effect:

1. the utility model discloses a set up the material and adjust the warehouse and realize reducing the particle concentration that smugglies secretly, participate in circulation and heat transfer in the flue gas rapidly in the boiler load reducing process for the heat transfer coefficient of convection heating surface reduces rapidly, thereby reduces steam temperature rapidly, realizes the effect of quick adjustment boiler load.

2. The utility model discloses a material conditioning storage storehouse is connected with air-blast device, can provide the return air for the bed material fluidization in the material conditioning storage storehouse, the bed material gets back to furnace through the return pipe. Because the bed material is still in a high-temperature state, the temperature in the hearth is improved, and the speed of increasing the load of the boiler is increased.

3. The utility model discloses set up the separator outside furnace, partial fine particle is brought into the separator by the fluidization wind and is caught by the separator, and the granule after catching returns furnace, realizes the circulation of material through the material returning valve.

Drawings

Fig. 1 is a schematic view of the overall structure of the present invention.

In the figure, 1, a hearth; 2. a separator; 3. a material return valve; 4. a wind distribution plate; 5. an air chamber;

6. primary air; 7. a material returning pipe; 8. a return gate; 9. returning the material wind; 10. a material adjusting storage bin;

11. a feed pipe; 12. a feed gate; 13. a flue gas duct; 14. a flue gas gate; 15. and a tail flue.

Detailed Description

To further disclose the contents, features and functions of the present invention, the following examples are given in detail with reference to the accompanying drawings.

Example (b): referring to the attached figure 1, the circulating fluidized bed boiler capable of rapidly adjusting the circulating ash amount comprises a hearth 1, a separator 2, a material returning valve 3, an air distribution plate 4 and an air chamber 5, wherein the air chamber 5 is arranged at the bottom of the hearth 1, and the air distribution plate 4 is arranged at the top of the air chamber 5. The upper part of the separator 2 is connected with the upper part of the hearth 1, the lower part of the separator 2 is connected with the material return valve 3, and the material return valve 3 is connected with the lower part of the hearth 1.

A material adjusting storage bin 10 is also arranged outside the hearth 1; the material adjusting storage bin 10 is connected with a blowing device and used for providing return air 9.

The upper portion of the material adjusting storage bin 10 is connected with the hearth 1 through a feeding pipe 11, and a feeding door 12 is arranged on the feeding pipe 11. The upper part of the material adjusting storage bin 10 is provided with a flue gas pipeline 13, and a flue gas door 14 is arranged on the flue gas pipeline 13. The flue gas duct 13 is connected to a back pass 15 at the top of the separator 2. A material returning pipe 7 is arranged at the lower part of the material adjusting storage bin 10, a material returning door 8 is arranged on the material returning pipe 7, and the material returning pipe 7 is connected to the bottom of the hearth 1.

The utility model discloses a theory of operation:

in the full-load working condition operation process of the circulating fluidized bed boiler, primary air 6 enters an air chamber 5 and enters a hearth 1 through an air distribution plate 4 to fluidize bed materials and fuel in the hearth 1, part of fine particles are brought out of the hearth 1 by fluidized air and enter a separator 2, most of particles are captured by the separator 2 and return to the hearth 1 through a material return valve 3, and a small part of ultrafine particles enter a tail flue 15 along with flue gas from the separator 2 to escape. At the moment, the feeding door 12, the flue gas door 14 and the return material door 8 of the material adjusting storage bin 10 are all in a closed state.

When the circulating fluidized bed boiler needs to rapidly reduce the load, the feeding door 12 and the flue gas door 14 are opened, and because the material adjusting storage bin 10 is connected with the tail flue 15, the pressure is low, circulating ash can continuously enter the material adjusting storage bin 10, so that the circulating ash in the hearth 1 is rapidly reduced. Because the materials in the hearth 1 are reduced, the heat transfer coefficient of the hearth 1 is reduced, the temperature of the hearth 1 is reduced, and the boiler output is rapidly reduced. The bed material is stored in a material conditioning silo 10 and maintained at its original temperature.

When the boiler needs to lift load, the feeding door 12 and the flue gas door 14 are closed, the return door 8 is opened, and return air 9 is provided, so that bed materials in the material adjusting storage bin 10 are fluidized, and the bed materials return to the hearth 1 through the return pipe 7. Since the bed material is still at a high temperature, it helps to increase the temperature in the furnace 1, so that the rate of boiler load increase is increased.

Although the preferred embodiments of the present invention have been described, the present invention is not limited to the above-mentioned embodiments, which are only illustrative and not restrictive, and those skilled in the art can make many forms without departing from the spirit and scope of the present invention. All of which fall within the scope of the present invention.

Claims

1. The utility model provides a circulating fluidized bed boiler of quick adjustment circulation ash volume, includes furnace, separator, return material valve, air distributor and plenum, its characterized in that: one or more material adjusting storage bins are also arranged outside the hearth; the material adjusting storage bin is connected with a blowing device.

2. The circulating fluidized bed boiler with rapid circulating ash amount adjustment according to claim 1, characterized in that: the upper part of the material adjusting storage bin is connected with the hearth through a feeding pipe, and a feeding door is arranged on the feeding pipe.

3. The circulating fluidized bed boiler with rapid circulating ash amount adjustment according to claim 1, characterized in that: and a flue gas pipeline is arranged at the upper part of the material adjusting storage bin, and a flue gas door is arranged on the flue gas pipeline.

4. The circulating fluidized bed boiler with rapid circulating ash amount adjustment according to claim 3, characterized in that: the flue gas pipeline is connected to a tail flue at the top of the separator.

5. The circulating fluidized bed boiler with rapid circulating ash amount adjustment according to claim 1, characterized in that: and a material returning pipe is arranged at the lower part of the material adjusting storage bin, a material returning door is arranged on the material returning pipe, and the material returning pipe is connected to the bottom of the hearth.

6. The circulating fluidized bed boiler for rapid adjustment of the amount of circulating ash according to any one of claims 1 to 5, wherein: an air chamber is arranged at the bottom of the hearth, and the air distribution plate is arranged at the top of the air chamber.

7. The circulating fluidized bed boiler for rapid adjustment of the amount of circulating ash according to any one of claims 1 to 5, wherein: the upper part of the separator is connected with the upper part of the hearth, the lower part of the separator is connected with the material return valve, and the material return valve is connected with the lower part of the hearth.