CN214745755U - Secondary combustion chamber structure and waste incineration system - Google Patents

Secondary combustion chamber structure and waste incineration system Download PDF

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Publication number
CN214745755U
CN214745755U CN202120290287.1U CN202120290287U CN214745755U CN 214745755 U CN214745755 U CN 214745755U CN 202120290287 U CN202120290287 U CN 202120290287U CN 214745755 U CN214745755 U CN 214745755U
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barrel
flue gas
combustion chamber
secondary air
chamber structure
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CN202120290287.1U
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蒋雪玲
刘朝阳
唐武
李邦强
温俊明
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Everbright Greentech Management Shenzhen Co ltd
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Everbright Greentech Management Shenzhen Co ltd
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Abstract

The utility model discloses a two combustion chamber structures and msw incineration system. The second combustion chamber structure comprises: the barrel, the vertical setting of barrel, barrel lower part side is provided with the flue gas entry, barrel upper portion side is provided with the exhanst gas outlet, the barrel bottom is provided with the slag notch, wherein, the inside venturi structure that sets to of barrel, high temperature flue gas is followed the flue gas entry process behind the venturi structure burning the exhanst gas outlet output. According to the utility model discloses a second combustion chamber structure, with the inside venturi structure that sets to of second combustion chamber barrel, increase the flue gas disturbance of flue gas when burning in the second combustion chamber, ensure the flue gas intensive mixing to abundant burning has reduced CO and has generated, makes the combustion products satisfy the useless requirement of burning of danger. Meanwhile, the inner part of the second combustion chamber is set into a Venturi structure, so that the flow rate of flue gas is reduced, and the manufacturing cost is reduced on the basis of meeting 1100 ℃/2 s.

Description

Secondary combustion chamber structure and waste incineration system
Technical Field
The utility model relates to a refuse treatment field particularly relates to a second combustion chamber structure and msw incineration system.
Background
According to the national records of dangerous waste, there are 46 general categories 479 of dangerous waste, and the nature of each batch of material is different, and the dangerous waste has various differences from the components, packaging forms or physical forms of the materials.
With the rapid development of the environmental protection industry, hazardous waste disposal gradually occupies the visual field of people, and the current typical hazardous waste disposal is mainly disposed by adopting an incineration technology, wherein combustion in a rotary kiln and a secondary combustion chamber form is widely adopted by people. However, the second combustion chamber used at present has the advantages of simple structure, large design flow rate, high equipment investment cost and poor secondary mixing effect of flue gas, and is not beneficial to burning out materials.
In order to solve the problems in the prior art, the utility model provides a two combustion chamber structures and msw incineration system.
SUMMERY OF THE UTILITY MODEL
In the summary section a series of concepts in a simplified form is introduced, which will be described in further detail in the detailed description section. The inventive content does not imply any attempt to define the essential features and essential features of the claimed solution, nor is it implied to be intended to define the scope of the claimed solution.
In order to solve the problems in the prior art, the utility model provides a second combustion chamber structure, include:
the barrel, the vertical setting of barrel, barrel lower part side is provided with the flue gas entry, barrel upper portion side is provided with the exhanst gas outlet, the barrel bottom is provided with the slag notch, wherein, the inside venturi structure that sets to of barrel, high temperature flue gas is followed the flue gas entry process behind the venturi structure burning the exhanst gas outlet output.
Illustratively, a secondary air port is arranged below the venturi structure.
Exemplarily, the secondary air inlets are uniformly distributed along the circumferential direction of the barrel.
Exemplarily, the secondary tuyere is configured to: and the secondary air input into the barrel from the secondary air port forms an included angle with the radial direction of the secondary air port, so that the secondary air input into the barrel from the plurality of secondary air ports forms a circulating flow.
Exemplarily, 12 secondary tuyeres are included and evenly distributed.
The secondary air control device is used for controlling the flow speed of secondary air input into the barrel through the secondary air opening.
Illustratively, the overfire air control means controls each of the plurality of overfire air ports to maintain a flow rate of overfire air supplied into the barrel at 50m/s or more while being opened.
For example, the secondary air control device controls the secondary air openings opened in the plurality of secondary air openings to be uniformly distributed on the circumference of the barrel.
Exemplarily, the secondary combustion chamber further comprises a flue gas flow rate control device arranged at the flue gas inlet and used for controlling the flue gas flow rate of the high-temperature flue gas entering the secondary combustion chamber.
The utility model also provides a waste incineration system, include as above arbitrary one the second combustion chamber structure.
According to the utility model discloses a second combustion chamber structure, with the inside venturi structure that sets to of second combustion chamber barrel, increase the flue gas disturbance of flue gas when burning in the second combustion chamber, ensure the flue gas intensive mixing to abundant burning has reduced CO and has generated, makes the combustion products satisfy the useless requirement of burning of danger. Meanwhile, the inner part of the second combustion chamber is set into a Venturi structure, so that the flow rate of flue gas is reduced, and the manufacturing cost is reduced on the basis of meeting 1100 ℃/2 s. According to the utility model discloses a waste incineration system has reduced the CO content in the high temperature flue gas of output, when having reduced manufacturing cost, satisfies the useless requirement of burning of danger.
Drawings
The following drawings of the present invention are used herein as part of the present invention for understanding the present invention. There are shown in the drawings, embodiments and descriptions of the invention, which are used to explain the principles of the invention.
In the drawings:
fig. 1 is a schematic structural view of a second combustion chamber structure according to an embodiment of the present invention;
fig. 2 is a schematic secondary air circulation diagram formed by secondary air input into the barrel through the secondary air inlet on the secondary combustion chamber structure according to an embodiment of the present invention.
Detailed Description
In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the present invention.
In order to thoroughly understand the present invention, a detailed description will be provided in the following description to explain the second combustion chamber structure and the waste incineration system of the present invention. It is apparent that the implementation of the invention is not limited to the specific details familiar to a person skilled in the art of semiconductors. The preferred embodiments of the present invention are described in detail below, however, other embodiments of the present invention are possible in addition to these detailed descriptions.
It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the invention. As used herein, the singular is intended to include the plural unless the context clearly dictates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
Exemplary embodiments according to the present invention will now be described in more detail with reference to the accompanying drawings. These exemplary embodiments may, however, be embodied in many different forms and should not be construed as limited to only the embodiments set forth herein. It is to be understood that these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of these exemplary embodiments to those skilled in the art. In the drawings, the thicknesses of layers and regions are exaggerated for clarity, and the same elements are denoted by the same reference numerals, and thus the description thereof will be omitted.
With the rapid development of the environmental protection industry, hazardous waste disposal gradually occupies the visual field of people, and the current typical hazardous waste disposal is mainly disposed by adopting an incineration technology, wherein combustion in a rotary kiln and a secondary combustion chamber form is widely adopted by people. However, the secondary combustion chamber used at present is simple in structure and high in equipment investment cost, secondary reburning effect of smoke is poor only by using secondary air mixing as a smoke disturbance mode, the smoke is difficult to burn out, the secondary combustion chamber outlet can reach the standard by adding a combustor, and energy consumption is high.
Example one
In order to solve the problems in the prior art, the utility model provides a second combustion chamber structure, include:
the barrel, the vertical setting of barrel, barrel lower part side is provided with the flue gas entry, barrel upper portion side is provided with the exhanst gas outlet, the barrel bottom is provided with the slag notch, wherein, the inside venturi structure that sets to of barrel, high temperature flue gas is followed the flue gas entry process behind the venturi structure burning the exhanst gas outlet output.
A second combustion chamber structure according to the present invention will be described by way of example with reference to fig. 1 and 2. Fig. 1 is a schematic structural view of a second combustion chamber structure according to an embodiment of the present invention; fig. 2 is a schematic secondary air circulation diagram formed by secondary air input into the barrel through the secondary air inlet on the secondary combustion chamber structure according to an embodiment of the present invention.
First, referring to fig. 1, a second combustion chamber structure according to the present invention includes a barrel 1.
Illustratively, the barrel 1 is communicated with an incinerator rotary kiln or a grate furnace, and flue gas generated by incinerating garbage in the incinerator rotary kiln or the grate furnace is input into the barrel 1 of the secondary combustion chamber for further combustion treatment.
Continuing to refer to fig. 1, according to the utility model discloses a barrel 1 vertical setting in second combustion chamber structure. Illustratively, the cartridge 1 is supported by a steel frame.
With continued reference to fig. 1, a flue gas inlet 11 is arranged on the side surface of the lower part of the cylinder 1, and the flue gas inlet is communicated with the incinerator rotary kiln or grate furnace, so that the flue gas in the incinerator rotary kiln or grate furnace is input into the cylinder 1 for further combustion.
The side surface of the upper part of the cylinder 1 is provided with a flue gas outlet 12, after being output from an incinerator rotary kiln or a grate furnace, flue gas is input into the cylinder 1 through a flue gas inlet 11 (as shown by an arrow A in figure 1), is combusted and ascends in the cylinder 1 of the secondary combustion chamber (as shown by an arrow B in figure 1), and generated high-temperature flue gas is discharged from the flue gas outlet 12 (as shown by an arrow C in figure 1).
Illustratively, the flue gas outlet 12 is connected with a waste heat boiler, and the waste heat boiler utilizes high-temperature flue gas discharged from the flue gas outlet 12 to perform heat exchange and then generate electricity and the like.
With continued reference to fig. 1, the bottom of the barrel 1 is provided with a slag outlet 13, and solid residues generated during the secondary combustion of the flue gas in the secondary chamber are discharged through the slag outlet 13 provided at the bottom of the barrel 1 (as indicated by arrow D in fig. 1).
With continued reference to fig. 1, disposed internally of the barrel 1 is a venturi structure 14. After high-temperature flue gas is input into the cylinder 1 from the flue gas inlet 11 (as shown by an arrow A in FIG. 1), the high-temperature flue gas rises in the cylinder 1 (as shown by an arrow B in FIG. 1), wherein the burner 2 arranged in the cylinder 1 is ignited, the flue gas is combusted in the cylinder and is disturbed by the Venturi structure 14 to enhance the combustion, and finally the generated high-temperature flue gas is discharged from the flue gas outlet 12 (as shown by an arrow C in FIG. 1).
Illustratively, barrel 1 inner structure builds by laying bricks or stones through refractory material and forms, exemplarily, as shown in fig. 1, venturi structure 14 sets up to the venturi throat, adopts refractory material to build by laying bricks or stones and forms, and like this, the venturi throat is built by piling up and setting up than the narrow pipeline of barrel and forms, and the setting form is simple, simultaneously, builds by laying bricks or stones through refractory material and forms venturi structure, and the structure that forms can satisfy structural strength design, can satisfy the purpose that the flue gas mixes the burning again.
Through setting up second combustion chamber inner structure into the venturi structure, the flue gas is when passing through the venturi structure, because the diameter of the flue gas circulation passageway of venturi structure both sides changes, makes the flue gas velocity of flow change, through venturi structure back flue gas velocity of flow greatly increased to increase the flue gas disturbance when the flue gas is burning in the second combustion chamber, ensure the flue gas intensive mixing, thereby the intensive combustion has reduced CO and has generated, makes the combustion products satisfy the useless requirement of handling of burning of danger. Meanwhile, the inner part of the second combustion chamber is set into a Venturi structure, and the disturbance of the flue gas is enhanced due to the Venturi structure, so that good flue gas disturbance and mixing effect can be achieved at low flue gas flow rate, good flue gas combustion effect is achieved, a combustor is not required to be additionally arranged at the outlet of the second combustion chamber for combustion, on the basis of meeting 1100 ℃/2s, the flue gas flow rate is reduced, and the construction cost of the second combustion chamber is reduced.
Illustratively, the flue gas flow rate at the flue gas inlet is set to not more than 2.5 m/s. Because the content of particulate matters in the flue gas is large when the flue gas is input into the secondary combustion chamber from the incinerator rotary kiln or the grate furnace for combustion, in order to reduce the scouring of the flue gas on the inner wall of the secondary combustion chamber and reduce the corrosion damage of the flue gas on the inner wall of the secondary combustion chamber, the flow velocity of the flue gas is set to be not more than 2.5 m/s.
Illustratively, the flow speed of the flue gas input by the flue gas inlet is controlled by a flue gas flow speed control device arranged at the flue gas inlet to be not more than 2.5 m/s. Illustratively, the flue gas flow rate control device comprises a valve arranged at the flue gas inlet, and the flue gas flow rate input into the cylinder from the flue gas inlet is controlled through the opening degree of the valve.
According to the utility model discloses an in the example, when the flue gas was imported to the second combustion chamber barrel from the flue gas entry, its flue gas velocity of flow was about 2.5m/s, after venturi structure flash mixed, the flue gas velocity of flow was up to 5m/s, has increased the flue gas disturbance.
With continued reference to fig. 1, the second combustion chamber structure according to the present invention further includes a secondary air port 15 disposed below the venturi structure 14. Set up the in-process of overgrate air 15 below the venturi structure inputting the overgrate air to barrel 1 inboard, mix with the flue gas in the barrel 1, disturb the flue gas, carry out the secondary with the flue gas after the overgrate air mixes at the in-process through the venturi structure to form the effect of mixing many times in the second combustion chamber, promoted the effect that the flue gas mixes, make the burning of flue gas in the second combustion chamber more abundant, reduce CO content, satisfy the useless requirement of burning the processing of burning of danger.
Illustratively, the flow rate of the overfire air supplied into the barrel 1 from the overfire air port 15 is set to 50m/s or more. The flow velocity of the secondary air is set to be more than 50m/s, so that the rigidity of the secondary air input into the cylinder from the secondary air port 15 is ensured, the disturbance effect of the secondary air on the smoke is ensured, and the secondary air and the smoke are fully mixed.
Illustratively, as shown in fig. 1, a plurality of secondary air ports 15 are uniformly distributed on the barrel 1 along the circumferential direction. In venturi structure below, evenly set up a plurality of overgrate air openings 15 along the circumferencial direction of barrel 1, ensure that the overgrate air distribution is even, form more effective disturbance.
Further, the secondary air opening arrangement 15 is, illustratively: the secondary air input into the barrel from the secondary air port forms an included angle with the radial direction of the secondary air port, so that the secondary air input into the barrel from the plurality of secondary air ports forms a circular flow, and the circular flow is concentric with the circumference of the secondary air port.
The overgrate air forms the circulation and forms the tangent ring to be arranged for the flue gas that rises in the barrel, further promotes the disturbance effect of overgrate air to the flue gas, promotes the mixed effect of overgrate air and flue gas.
In an example according to the present invention, 12 secondary air nozzles are uniformly arranged in the circumferential direction of the cylinder 1.
Referring to fig. 2, there is shown a schematic sectional view of the arrangement of the secondary air ports 15 on the circumference of the barrel 1 according to an embodiment of the present invention, wherein 12 secondary air ports are uniformly arranged along the circumferential direction of the barrel 1, wherein 6 secondary air ports 15 are provided every 25 ° on one side (shown on the left side in fig. 2) of the circumference of the barrel 1, 6 secondary air ports 15 are provided every 25 ° on the other side (shown on the right side in fig. 2) of the circumference of the barrel 1, the secondary air ports 15 between the above-mentioned both sides of the barrel 1 are separated by 45 ° (two secondary air ports 15 located on both sides of the central axis EE in fig. 2), and the secondary air inputted from the secondary air ports 15 into the inside of the barrel 1 is angled in the radial direction of the secondary air ports 15 to form a circular flow in the barrel 1, and the circular flow forms a concentric circle with the circumference where the secondary air ports 15 are located.
Further, exemplarily, according to the utility model discloses a second combustion chamber structure still includes the overgrate air controlling means who carries out control to the air supply volume of overgrate air mouth, through overgrate air controlling means controls the air supply volume of overgrate air mouth, ensures that the velocity of flow of overgrate air in overgrate air mouth input barrel 1 remains at the design value all the time, guarantees the disturbance effect and the mixed effect of overgrate air to the flue gas.
In an example according to the present invention, the secondary air control device includes a regulating valve provided corresponding to each secondary air opening, and the amount of air supplied to the secondary air opening can be adjusted by the regulating valve, and the secondary air opening can be opened and closed.
For example, in one example of the present invention, 12 secondary air ports 15 are arranged on the barrel 1, and the flow rate of the secondary air inputted into the barrel 1 through each opened secondary air port 15 is not lower than 50 m/s; the secondary air volume required for combustion in the cylinder 1 designed at this time is 1000 units. Under the condition that only 5000 units of secondary air volume are needed in actual combustion, if 12 secondary air ports are all opened, the flow velocity cannot reach the state that the designed flow velocity is not lower than 50 m/s. In order to ensure the flow velocity, in this case, closing 12 nozzles to 6 ensures that the flow velocity of the nozzles is always kept above 50m/s, thereby ensuring the rigidity of the secondary air and the disturbance effect of the secondary air on the smoke.
In an example according to the present invention, the overfire air control means controls the plurality of overfire air openings opened therein to be uniformly distributed on the circumference of the cylinder.
For example, when 6 secondary tuyeres of 12 secondary tuyeres need to be closed, every two secondary tuyeres are closed, so that a closed secondary tuyere is arranged between every two adjacent opened secondary tuyeres, the opened secondary tuyeres are still uniformly distributed on the circumference of the barrel, and finally, the secondary air input into the barrel from the secondary tuyeres is uniformly distributed in the barrel, so that the secondary air and the flue gas are fully and moderately proportioned, and the optimal effect of reducing the emission of unburnt substances and CO in the flue gas is achieved.
Example two
The utility model also provides a waste incineration system, include as embodiment one the second combustion chamber structure.
Because according to the utility model discloses a second combustion chamber structure, with the inside venturi structure that sets to of second combustion chamber barrel, increase the flue gas disturbance of flue gas when burning in the second combustion chamber, ensure the flue gas intensive mixing to abundant burning has reduced CO and has generated, makes the combustion products satisfy the useless requirement of burning of danger. Meanwhile, the inner part of the second combustion chamber is set into a Venturi structure, so that the flow rate of flue gas is reduced, and the manufacturing cost is reduced on the basis of meeting 1100 ℃/2 s. According to the utility model discloses a waste incineration system has reduced the CO content in the high temperature flue gas of output, when having reduced manufacturing cost, satisfies the useless requirement of burning of danger.
The present invention has been described in terms of the above embodiments, but it is to be understood that the above embodiments are for purposes of illustration and description only and are not intended to limit the invention to the described embodiments. Furthermore, it will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that many more modifications and variations are possible in light of the teaching of the present invention and are within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (10)

1. A second combustion chamber structure, comprising:
the barrel, the vertical setting of barrel, barrel lower part side is provided with the flue gas entry, barrel upper portion side is provided with the exhanst gas outlet, the barrel bottom is provided with the slag notch, wherein, the inside venturi structure that sets to of barrel, high temperature flue gas is followed the flue gas entry process behind the venturi structure burning the exhanst gas outlet output.
2. The secondary combustion chamber structure of claim 1, wherein a secondary air port is provided below the venturi structure.
3. The secondary combustion chamber structure of claim 2, comprising a plurality of secondary tuyeres uniformly distributed along a circumferential direction of the barrel.
4. The secondary combustion chamber structure of claim 3, wherein the secondary tuyere is provided: and the secondary air input into the barrel from the secondary air port forms an included angle with the radial direction of the secondary air port, so that the secondary air input into the barrel from the plurality of secondary air ports forms a circulating flow.
5. The secondary combustion chamber structure of claim 3, comprising 12 secondary tuyeres uniformly distributed.
6. The secondary combustion chamber structure of claim 3, further comprising a secondary air control device for controlling a flow rate of secondary air supplied into the barrel through the secondary air port.
7. The secondary combustion chamber structure according to claim 6, wherein the secondary air control means controls each of the plurality of secondary air ports to maintain a flow velocity of the secondary air, which is inputted into the barrel with being opened, at 50m/s or more.
8. The secondary combustion chamber structure of claim 6, wherein the secondary air control means controls the secondary air ports opened among the plurality of secondary air ports to be uniformly distributed on the circumference of the barrel.
9. The secondary combustion chamber structure of claim 1, further comprising a flue gas flow rate control device arranged at the flue gas inlet, and used for controlling the flue gas flow rate of high-temperature flue gas entering the secondary combustion chamber.
10. A waste incineration system comprising the secondary combustion chamber structure of any one of claims 1-9.
CN202120290287.1U 2021-02-01 2021-02-01 Secondary combustion chamber structure and waste incineration system Active CN214745755U (en)

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CN202120290287.1U CN214745755U (en) 2021-02-01 2021-02-01 Secondary combustion chamber structure and waste incineration system

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Application Number Priority Date Filing Date Title
CN202120290287.1U CN214745755U (en) 2021-02-01 2021-02-01 Secondary combustion chamber structure and waste incineration system

Publications (1)

Publication Number Publication Date
CN214745755U true CN214745755U (en) 2021-11-16

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