Pulverized coal concentration regulator of coal-fired boiler

Abstract

The embodiment of the invention provides a coal-fired boiler pulverized coal concentration regulator which comprises a shell, a first separation part, a second separation part and a partition plate, the shell is provided with an inlet, an outlet and a flowing space, the flowing space is communicated with the inlet and the outlet, and the first separation part and the second separation part are arranged in the flowing direction of pulverized coal. The first separation part, the second separation part and the partition plate are sequentially arranged in the flowing space, the second separation part is arranged on the shell in a rotatable mode, the partition plate extends to the outlet in the flowing direction of pulverized coal, and the partition plate divides the outlet into two parts. According to the pulverized coal concentration regulator for the coal-fired boiler, the second separation part is arranged on the shell in a rotating mode, and the concentration ratio of pulverized coal subjected to secondary separation can be adjusted by adjusting the rotating angle of the second separation part, so that the ratio of the pulverized coal separated by the pulverized coal concentration regulator for the coal-fired boiler is flexibly adjusted and controlled, and the pulverized coal concentration requirements of a combustor under different working conditions are met; the burn-off rate and the combustion effect of pulverized coal in the combustor are improved, low-load stable combustion is achieved, and meanwhile the emission amount of NOx is reduced.

Description

Technical Field

[0001] The embodiments of the present disclosure belong to the technical field of boiler equipment, and specifically relate to a pulverized coal concentration regulator for a coal-fired boiler. Background Art

[0002] Deep peak regulation is a state in which the power plant reduces its output and operates at a lower load. However, under this operating condition, the boiler will have problems such as uneven flame distribution in the furnace and insufficient power, resulting in a large temperature deviation in the water-cooled wall, and even causing a safety accident of overheating and bursting of the metal tube wall. Ultra-low NOx emissions are also an environmental protection goal pursued by thermal power plants, but this requires sacrificing the temperature of the combustion area, which affects the fuel of the pulverized coal. To achieve low-load stable combustion, especially under the current 20%-30% deep peak regulation demand, the existing burner layout is difficult to meet the requirements. When the unit is running at a lower load, it will also face the problem of too low furnace temperature. The pulverized coal is separated into thick and thin. A moderate increase in the concentration of the pulverized coal can reduce the ignition heat of the pulverized coal, advance the ignition of the pulverized coal, and thus increase the overall temperature level of the furnace. The thick and thin pulverized coal separator can make the pulverized coal entering the burner burn better, achieve low-load stable combustion and reduce NOx emissions.

[0003] In the related art, the structure of a single elbow or blunt body separator has the problem of unsatisfactory separation effect, and it is difficult to meet the requirements of the burner for different concentrations of coal powder under different working conditions. Summary of the invention

[0004] The embodiments of the present disclosure aim to solve at least one of the technical problems existing in the prior art and provide a pulverized coal concentration regulator for a coal-fired boiler.

[0005] An embodiment of the present disclosure provides a pulverized coal concentration regulator for a coal-fired boiler, the pulverized coal concentration regulator for a coal-fired boiler comprising: a shell, a first separator, a second separator and a partition plate, the shell having an inlet, an outlet and a flow space, the flow space connecting the inlet and the outlet, along the flow direction of the pulverized coal, the first separator, the second separator and the partition plate are sequentially arranged in the flow space, the second separator is rotatably arranged on the shell, the partition plate extends to the outlet along the flow direction of the pulverized coal, and the partition plate divides the outlet into two parts.

[0006] In some embodiments of the present disclosure, the first separator is disposed at the top or upper portion of the flow space.

[0007] In some embodiments of the present disclosure, the second separator is disposed in the middle or upper portion of the flow space.

[0008] In some embodiments of the present disclosure, a rotation axis of the second separation element is perpendicular to a flow direction of the coal powder.

[0009] In some embodiments of the present disclosure, one side of the second separator is a flat plate extending along the length direction of the second separator, and the other side of the second separator is an arc-shaped protrusion extending along the length direction of the second separator.

[0010] In some embodiments of the present disclosure, the pulverized coal concentration regulator of a coal-fired boiler includes: a bolt, a fixing part and a nut, the two bolts are arranged oppositely at the two ends of the second separation part, each bolt is passed through the shell, the fixing part is connected to the outside of the shell, and the bolt is connected to the nut after passing through the fixing part.

[0011] In some embodiments of the present disclosure, the shell includes a converging pipe section and a diverting pipe section, the converging pipe section is connected to the diverting pipe section, the inlet is provided at one end of the converging pipe section away from the diverting pipe section, and the outlet is provided at one end of the diverting pipe section away from the converging pipe section.

[0012] In some embodiments of the present disclosure, the first separator and the second separator are both disposed in the confluent pipe section, the partition plate extends from the confluent pipe section to the outlet, and the partition plate divides the diversion pipe section into an upper channel and a lower channel.

[0013] In some embodiments of the present disclosure, along a direction perpendicular to the flow of the coal powder, a cross-sectional area of ​​the upper channel is greater than a cross-sectional area of ​​the lower channel.

[0014] In some embodiments of the present disclosure, the inner diameter of the diversion pipe section is greater than the inner diameter of the confluence pipe section.

[0015] The pulverized coal concentration regulator of a coal-fired boiler of the disclosed embodiment includes a shell, a first separator, a second separator and a partition plate. Specifically, the shell has a flow space. Along the flow direction of the pulverized coal, the first separator, the second separator and the partition plate are sequentially arranged in the flow space. The pulverized coal enters the flow space through the inlet of the shell and passes through the first separator, the second separator and the partition plate in sequence. The pulverized coal is separated once by the first separator, and then the pulverized coal after the primary separation is separated twice by the second separator to further separate the pulverized coal into thick and thin. After the secondary separation, the pulverized coal enters two channels separated by the partition plate, and finally passes through the two parts of the outlet separated by the separation plate and is discharged from the shell. The second separator is arranged on the shell in a rotating manner. By adjusting the rotation angle of the second separator, the thick and thin ratio of the pulverized coal after the secondary separation can be adjusted, so as to flexibly adjust the ratio of the pulverized coal separated by the pulverized coal concentration regulator of the coal-fired boiler to meet the pulverized coal concentration requirements under different working conditions of the burner, improve the burnout rate and combustion effect of the pulverized coal in the burner, achieve low-load stable combustion, and reduce NOx emissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a first schematic diagram of a pulverized coal concentration regulator for a coal-fired boiler according to an embodiment of the present disclosure;

[0017] Figure 2 This is a second schematic diagram of a pulverized coal concentration regulator for a coal-fired boiler according to an embodiment of the present disclosure.

[0018] The reference numerals in the accompanying drawings represent the following:

[0019] 1. Shell; 2. Lower channel; 3. Upper channel; 4. Partition plate; 5. Second separation piece; 6. First separation piece; 7. Converging pipe section; 8. Diverting pipe section; 9. Bolts; 10. Fixing piece; 11. Nuts; 101. Inlet; 102. Outlet; 103. Flow space. DETAILED DESCRIPTION

[0020] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0021] It should be understood that the terms used herein are only for the purpose of describing specific example embodiments and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "an" and "said" as used herein may also be meant to include plural forms. The terms "include", "comprise", "contain", and "have" are inclusive, and therefore specify the existence of stated features, steps, operations, elements and / or parts, but do not exclude the existence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. The method steps, processes, and operations described herein are not interpreted as necessarily requiring them to be performed in the specific order described or illustrated, unless the execution order is clearly indicated. It should also be understood that additional or alternative steps may be used.

[0022] Although the terms first, second, third, etc. can be used in the text to describe multiple elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates, terms such as "first", "second" and other numerical terms do not imply order or sequence when used in the text. Therefore, the first element, component, region, layer or section discussed below can be referred to as the second element, component, region, layer or section without departing from the teaching of the example embodiments.

[0023] For ease of description, spatial relative terms may be used herein to describe the relationship of one element or feature relative to another element or feature as shown in the figure, such as "inside", "outside", "inner side", "outer side", "below", "below", "above", "above", etc. Such spatial relative terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figure. For example, if the device in the figure is turned over, then the elements described as "below other elements or features" or "below other elements or features" will subsequently be oriented as "above other elements or features" or "above other elements or features". Therefore, the example term "below..." can include both upper and lower orientations. The device can be oriented otherwise (rotated 90 degrees or in other directions) and the spatial relative descriptors used in the text are interpreted accordingly.

[0024] like Figure 1 , Figure 2 As shown, an embodiment of the present disclosure provides a pulverized coal concentration regulator for a coal-fired boiler, the pulverized coal concentration regulator for a coal-fired boiler comprising: a shell 1, a first separator 6, a second separator 5 and a partition plate 4, the shell 1 having an inlet 101, an outlet 102 and a flow space 103, the flow space 103 connecting the inlet 101 and the outlet 102, along the flow direction of the pulverized coal, the first separator 6, the second separator 5 and the partition plate 4 are sequentially arranged in the flow space 103, the second separator 5 is rotatably arranged on the shell 1, the partition plate 4 extends to the outlet 102 along the flow direction of the pulverized coal, and the partition plate 4 divides the outlet 102 into two parts.

[0025] The pulverized coal concentration regulator of a coal-fired boiler of the disclosed embodiment includes a shell 1, a first separator 6, a second separator 5 and a partition plate 4. Specifically, the shell 1 has a flow space 103. Along the flow direction of the pulverized coal, the first separator 6, the second separator 5 and the partition plate 4 are sequentially arranged in the flow space 103. The pulverized coal enters the flow space 103 through the inlet 101 of the shell 1, and passes through the first separator 6, the second separator 5 and the partition plate 4 in sequence. The pulverized coal is separated once by the first separator 6, and then the pulverized coal after the first separation is separated twice by the second separator 5 to further separate the pulverized coal into light and thick ones. After the secondary separation, the pulverized coal enters the two channels separated by the partition plate 4, and is finally discharged from the shell 1 in two parts through the outlet 102 separated by the separation plate. The second separation element 5 is rotatably arranged on the shell 1. By adjusting the rotation angle of the second separation element 5, the concentration ratio of the coal powder after the secondary separation can be adjusted, so as to flexibly control the proportion of the coal powder separated by the coal powder concentration regulator of the coal-fired boiler to adapt to the coal powder concentration requirements under different working conditions of the burner, improve the burnout rate and combustion effect of the coal powder in the burner, realize low-load stable combustion, and reduce NOx emissions.

[0026] In some embodiments of the present disclosure, the housing 1 includes a converging pipe section 7 and a diverging pipe section 8, the converging pipe section 7 is connected to the diverging pipe section 8, the space in the converging pipe section 7 and the space in the diverging pipe section 8 together constitute a flow space 103, the converging pipe section 7 is provided with an inlet 101 at one end away from the diverging pipe section 8, and the diverging pipe section 8 is provided with an outlet 102 at one end away from the converging pipe section 7. The pulverized coal enters the converging pipe section 7 through the inlet 101, and is separated into two pulverized coal airflows with different concentrations in the converging pipe section 7. The two pulverized coal airflows with different concentrations enter the diverging pipe section 8, and flow to the outlet 102 through two parts of the diverging pipe section 8, respectively, and finally the two pulverized coal airflows with different concentrations are discharged from the housing 1 through two parts of the outlet 102. Specifically, the converging pipe section 7 and the separation pipe section are both straight pipe sections.

[0027] In some embodiments of the present disclosure, the first separator 6 and the second separator 5 are both disposed in the converging pipe section 7, and the first separator 6 and the second separator 5 are sequentially disposed along the flow direction of the coal powder. The coal powder enters the converging pipe section 7 through the inlet 101, and as the coal powder continues to flow forward, the coal powder is separated once by the first separator 6, and the coal powder after the first separation continues to flow forward, and the coal powder after the first separation is separated twice by the second separator 5, and the coal powder after the second separation is separated into two coal powder airflows with different concentrations.

[0028] The partition plate 4 extends from the converging pipe section 7 to the diverging pipe section 8, and the partition plate 4 extends to the outlet 102, and the partition plate 4 divides the diverging pipe section 8 into an upper channel 3 and a lower channel 2. The pulverized coal after secondary separation is separated into two pulverized coal airflows with different concentrations, and the two pulverized coal airflows with different concentrations enter the upper channel 3 and the lower channel 2 of the diverging pipe section 8 respectively, so as to isolate the two pulverized coal airflows with different concentrations, avoid mixing the two pulverized coal airflows with different concentrations, and ensure that the concentration of the pulverized coal delivered to the burner by the pulverized coal concentration regulator meets the requirements of the burner.

[0029] In some embodiments of the present disclosure, along the flow direction perpendicular to the pulverized coal, the cross-sectional area of ​​the upper channel 3 is greater than the cross-sectional area of ​​the lower channel 2. By setting the upper channel 3 and the lower channel 2 to have different cross-sectional areas, the space sizes of the upper channel 3 and the lower channel 2 are different. Even if the upper channel 3 and the lower channel 2 allow different airflows to pass through, the ratio of two airflows of different concentrations entering the burner can be adjusted through the upper channel 3 and the lower channel 2 of different space sizes.

[0030] In some embodiments of the present disclosure, the inner diameter of the diversion pipe section 8 is larger than the inner diameter of the confluence pipe section 7. The coal powder flows from the confluence pipe section 7 with a smaller inner diameter into the diversion pipe section 8 with a larger inner diameter, which can reduce the resistance of the coal powder flowing from the confluence pipe section 7 to the diversion pipe section 8.

[0031] In some embodiments of the present disclosure, the first separator 6 is disposed at the top or upper part of the flow space 103. Specifically, the first separator 6 is fixedly disposed on the inner wall of the confluent pipe section 7, the first separator 6 is located in the confluent pipe section 7, and the first separator 6 is located at the top or upper part of the confluent pipe section 7. The coal powder enters the confluent pipe section 7 from the inlet 101. When the coal powder contacts the first separator 6, the flow trajectory of the coal powder changes under the combined action of inertia and collision force, and most of the coal powder continues to flow forward from the bottom of the first separator 6, that is, most of the coal powder flows in the middle and lower part of the confluent pipe section 7, wherein most of the coal powder is coal powder with a higher concentration, and the remaining small part of the coal powder bypasses the first separator 6 and flows in the upper part of the confluent pipe section 7, wherein the small part of the coal powder is coal powder with a lower concentration.

[0032] In some embodiments of the present disclosure, the second separator 5 is disposed in the middle or upper part of the flow space 103. Specifically, the second separator 5 is disposed in the confluent pipe section 7, and the second separator 5 is located in the middle or upper part of the confluent pipe section 7. The coal powder after the first separation is divided into a large part of coal powder with a higher concentration and a small part of coal powder with a lower concentration. The two parts of coal powder may collide with the second separator 5 during the forward flow. After the part of the coal powder after the first separation contacts the second separator 5, under the combined action of inertia and collision force, the trajectory of the part of the coal powder after the first separation may change. A small part of the coal powder in contact with the second separator 5 bypasses the second separator 5 and enters the light side channel, and most of it enters the concentrated side channel, thereby realizing the secondary separation of the coal powder and improving the separation degree of the coal powder.

[0033] Furthermore, the second separator 5 is rotatably arranged in the converging pipe section 7. By adjusting the rotation angle of the second separator 5, the ratio of the two coal powders with different concentrations after separation by the second separator 5 can be adjusted, thereby achieving precise control of the concentration of the coal powder separated by the coal powder separator, ensuring that the proportion of coal powder delivered to the burner meets the requirements of the burner and adapting to the requirements of the burner for coal powder of different concentrations under different working conditions.

[0034] In some embodiments of the present disclosure, the rotating axis of the second separator 5 is perpendicular to the flow direction of the coal powder. By rotating the second separator 5, the coal powder can be made to contact or collide with different positions of the second separator 5, and the contact area between the coal powder and the second separator 5 can also be changed. The larger the contact area between the coal powder and the second separator 5, the more the second separator 5 can change the flow trajectory of the coal powder, that is, adjust the ratio of the coal powder whose flow trajectory is changed to the coal powder whose flow trajectory is not changed, that is, adjust the ratio of the coal powder whose flow trajectory is changed to the coal powder that bypasses the second separator 5, so as to adjust the ratio of the coal powder entering the rich side channel and the lean side channel.

[0035] In some embodiments of the present disclosure, one side of the second separator 5 is a flat plate extending along the length direction of the second separator 5 , and the other side of the second separator 5 is an arc-shaped protrusion extending along the length direction of the second separator 5 . When the second separating member 5 is in the initial position, the flat plate of the second separating member 5 faces upward and the arc-shaped protrusion faces downward, the coal powder after one separation contacts with the second separating member 5, and most of the coal powder changes its trajectory under the combined action of inertia and collision force, and flows forward to the lower channel 2 at the lower part of the converging pipe section 7. At this time, the lower channel 2 is a concentrated side channel, and a small part of the coal powder bypasses the second separating member 5 and flows forward to the upper channel 3 at the upper part of the converging pipe section 7. At this time, the upper channel 3 is a lean side channel; when the second separating member 5 rotates 30 to 60° counterclockwise from the initial position, most of the coal powder after one separation contacts with the flat plate of the second separating member 5. Since the flat plate rotates 30 to 60° counterclockwise, that is, the right side of the flat plate is higher than the left side of the flat plate, most of the coal powder changes its trajectory under the combined action of inertia and collision force, and flows along the upper part of the converging pipe section 7. The pulverized coal flows to the upper channel 3. At this time, the upper channel 3 is the concentrated side channel. A small part of the pulverized coal after the first separation bypasses the second separator 5 and flows to the lower channel 2 at the lower part of the confluent pipe section 7. At this time, the lower channel 2 is the dilute side channel. When the second separator 5 rotates 30 to 60° clockwise from the initial position, most of the pulverized coal after the first separation contacts the flat plate of the second separator 5. Since the flat plate rotates 30 to 60° clockwise, the right side of the flat plate is lower than the left side of the flat plate, that is, the left side of the arc-shaped protrusion is higher than the right side. Under the combined action of inertia and collision force, the trajectory of most of the pulverized coal changes and flows along the lower part of the confluent pipe section 7 to the lower channel 2. At this time, the lower channel 2 is the concentrated side channel. A small part of the pulverized coal after the first separation bypasses the second separator 5 and flows to the upper channel 3 at the upper part of the confluent pipe section 7. At this time, the upper channel 3 is the dilute side channel. Therefore, the ratio of the coal powder in the upper channel 3 to the coal powder in the lower channel 2 can be adjusted by adjusting the rotation angle of the second separator 5, and the concentration of the upper channel 3 and the lower channel 2 can be adjusted by adjusting the rotation direction of the second separator 5.

[0036] In this embodiment, the first separator 6 has the same structure as the second separator 5 , that is, one side of the first separator 6 is a flat plate, the other side of the first separator 6 is an arc-shaped protrusion, and one side of the flat plate of the first separator 6 is connected to the inner wall of the confluence pipe section 7 .

[0037] In some embodiments of the present disclosure, a pulverized coal concentration regulator for a coal-fired boiler includes: a bolt 9, a fixing member 10 and a nut 11, wherein two bolts 9 are arranged at opposite ends of a second separator 5, each bolt 9 is passed through the shell 1, and the fixing member 10 is connected to the outside of the shell 1. The bolt 9 is passed through the fixing member 10 and then connected to the nut 11. Specifically, the fixing member 10 is a fixing groove, and the fixing groove is adapted to the outer wall of the shell 1 to ensure the reliability of the connection between the bolt 9 and the nut 11. When the angle of the second separator 5 needs to be adjusted, the two nuts 11 at both ends of the second separator 5 are loosened respectively, and then the second separator 5 is rotated to the corresponding position, and finally the two nuts 11 are tightened respectively, so as to adjust the angle of the second separator 5.

[0038] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present disclosure, but the present disclosure is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and substance of the present disclosure, and these modifications and improvements are also considered to be within the scope of protection of the present disclosure.

Claims

1. A pulverized coal concentration regulator for a coal-fired boiler, characterized in that: The pulverized coal concentration regulator of a coal-fired boiler includes: a shell, a first separator, a second separator and a partition plate. The shell has an inlet, an outlet and a flow space. The flow space connects the inlet and the outlet. Along the flow direction of the pulverized coal, the first separator, the second separator and the partition plate are sequentially arranged in the flow space. The second separator is rotatably arranged on the shell. The partition plate extends to the outlet along the flow direction of the pulverized coal. The partition plate divides the outlet into two parts.

2. The pulverized coal concentration regulator for a coal-fired boiler according to claim 1, characterized in that: The first separation element is arranged at the top or upper part of the flow space.

3. The pulverized coal concentration regulator for a coal-fired boiler according to claim 1, characterized in that: The second separation element is arranged in the middle or upper part of the flow space.

4. The pulverized coal concentration regulator for a coal-fired boiler according to claim 1, characterized in that: The rotation axis of the second separation element is perpendicular to the flow direction of the coal powder.

5. The pulverized coal concentration regulator for a coal-fired boiler according to claim 1, characterized in that: One side of the second separation member is a flat plate extending along the length direction of the second separation member, and the other side of the second separation member is an arc-shaped protrusion extending along the length direction of the second separation member.

6. The pulverized coal concentration regulator for a coal-fired boiler according to claim 1, characterized in that: The pulverized coal concentration regulator for a coal-fired boiler includes: a bolt, a fixing and a nut, wherein the two bolts are arranged oppositely at the two ends of the second separation member, each of the bolts is passed through the shell, the fixing is connected to the outside of the shell, and the bolt is connected to the nut after passing through the fixing.

7. The pulverized coal concentration regulator for a coal-fired boiler according to claim 1, characterized in that: The shell comprises a converging pipe section and a diverting pipe section, the converging pipe section is connected to the diverting pipe section, the converging pipe section has an end away from the diverting pipe section provided with the inlet, and the diverting pipe section has an end away from the converging pipe section provided with the outlet.

8. The pulverized coal concentration regulator for a coal-fired boiler according to claim 7, characterized in that: The first separator and the second separator are both arranged in the converging pipe section, the partition plate extends from the converging pipe section to the diverting pipe section and to the outlet, and the partition plate divides the diverting pipe section into an upper channel and a lower channel.

9. The pulverized coal concentration regulator for a coal-fired boiler according to claim 8, characterized in that: Along a direction perpendicular to the flow direction of the coal powder, the cross-sectional area of ​​the upper channel is larger than the cross-sectional area of ​​the lower channel.

10. The pulverized coal concentration regulator for a coal-fired boiler according to claim 7, characterized in that: The inner diameter of the diversion pipe section is greater than the inner diameter of the confluence pipe section.

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