Soot blowing system suitable for ash deposition area of horizontal flue

Abstract

The invention belongs to the technical field of thermal power generation, and particularly relates to a soot blowing system suitable for a horizontal flue soot deposition area, the soot blowing system suitable for the horizontal flue soot deposition area comprises multiple sets of soot blowing structures and a gas storage tank, the gas outlet end of the gas storage tank is connected with the multiple sets of soot blowing structures, and the gas outlet end of the gas storage tank is connected with the soot blowing structures; one end of each soot blowing structure is arranged outside the horizontal flue and connected with the gas outlet end of the gas storage tank; the other ends of the gas inlet pipes and the gas outlet pipes are arranged in the horizontal flue and located at the furnace arch of the horizontal flue; and each soot blowing structure positioned at the furnace arch of the horizontal flue is provided with a plurality of spray holes. The multiple sets of soot blowing structures are arranged at the furnace arch of the horizontal flue to blow accumulated soot in the horizontal flue, and the soot blowing device has the advantage of being high in soot blowing efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of thermal power generation, and in particular relates to a soot blowing system suitable for a soot accumulation area of ​​a horizontal flue. Background Art

[0002] When the coal-fired power unit boiler is operating at low load for deep peak regulation, the smoke velocity in the horizontal flue area of ​​the boiler decreases. The excessively low smoke velocity cannot carry away the ash deposited in the horizontal flue area, especially for boilers burning high-ash coal. The ash accumulation height can even reach more than 1 meter under low load.

[0003] In the prior art, a steam sootblower is used to clean the ash deposited in the horizontal flue. However, when the steam sootblower is used to blow the ash, the steam carries the ash deposited, thereby increasing the wear rate of the high-temperature reheater tube bank and reducing the heat exchange area of ​​the high-temperature reheater tube bank.

[0004] Chinese patent application: CN107883388A provides a soot blowing system and method for a π-type boiler flame angle, which achieves the blowing of accumulated soot by arranging a hood-type soot blower on the diaphragm of the upper slope of the flame angle between the high-temperature superheater and the high-temperature reheater inside the π-type boiler and passing through the upper slope of the flame angle. However, the patent has the problem of low soot blowing efficiency.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] In order to solve the technical problems existing in the prior art, the present invention provides a soot blowing system suitable for the soot accumulation area of ​​the horizontal flue. The present invention arranges multiple groups of soot blowing structures at the flame deflection angle of the horizontal flue to blow away the soot accumulated in the horizontal flue, which has the advantage of high soot blowing efficiency.

[0007] The present invention includes the following technical solutions:

[0008] The present invention provides a sootblowing system suitable for the soot accumulation area of ​​a horizontal flue, comprising a plurality of sootblowing structures and an air storage tank, wherein the air outlet ends of the air storage tanks are respectively connected to the plurality of sootblowing structures, one end of each of the plurality of sootblowing structures is arranged outside the horizontal flue and connected to the air outlet end of the air storage tank; the other end is arranged in the horizontal flue and located at the flame folding angle of the horizontal flue; each of the sootblowing structures located at the flame folding angle of the horizontal flue is provided with a plurality of spray holes.

[0009] Furthermore, the soot blowing structure includes a first pipe section and a second pipe section, the first pipe section is located outside the horizontal flue, and the second pipe section is located inside the horizontal flue; one end of the first pipe section is used to connect to the air outlet end of the gas storage tank, and the other end is connected to one end of the second pipe section; a valve is provided on the first pipe section, and a plurality of the spray holes are provided on the second pipe section.

[0010] Furthermore, the second pipe section includes two parallel pipes, and each pipe is provided with a plurality of the spray holes.

[0011] Furthermore, the two pipelines are arranged in parallel, and two spray holes are arranged on each pipeline, and the two spray holes on one pipeline are staggered with the two spray holes on the other pipeline.

[0012] Furthermore, the valve includes a ball valve and an electric valve.

[0013] Furthermore, a nozzle is provided on the spray hole, and the nozzle includes a first conical section, a first cylindrical section, a second conical section and a second cylindrical section, the end of the first conical section with a larger diameter takes in air, the end of the first conical section with a smaller diameter is connected to one end of the first cylindrical section, the other end of the first cylindrical section is connected to the end of the second conical section with a smaller diameter, the end of the second conical section with a larger diameter is connected to one end of the second cylindrical section, and the other end of the second cylindrical section discharges air.

[0014] Furthermore, the gas outlet end of the gas storage tank is connected to a plurality of soot blowing structures through a first pipeline.

[0015] Furthermore, a stop valve and a pressure gauge are sequentially arranged on the first pipeline along the gas flow direction.

[0016] Furthermore, the air inlet end of the air storage tank is connected to a second pipeline.

[0017] Furthermore, a filter, a check valve and a stop valve are sequentially arranged on the second pipeline along the gas flow direction.

[0018] By adopting the above technical solution, the present invention has the following advantages:

[0019] 1. The present invention arranges multiple groups of soot blowing structures at the flame deflection angle of the horizontal flue. The nozzles of the soot blowing structures spray compressed air jets from multiple directions. The compressed air rolls up the accumulated ash in the horizontal flue, destroys the original sedimentation equilibrium state of the accumulated ash, and forces the accumulated ash to become a flocculent state and flow away with the flow of the flue gas, thereby removing the ash. The invention has the advantage of high soot blowing efficiency.

[0020] 2. The soot blowing system of the present invention can use compressed air as a medium, which can prevent fly ash from compacting and effectively reduce the ash accumulation in the horizontal flue of the boiler, ensuring that the ash accumulation height in the horizontal flue does not exceed 0.2m.

[0021] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 This is a structural schematic diagram of a soot blowing system suitable for a soot accumulation area of ​​a horizontal flue in an embodiment of the present invention;

[0024] Figure 2 It is a schematic diagram of the connection structure between the soot blowing structure and the horizontal flue in an embodiment of the present invention;

[0025] Figure 3 Schematic diagram of the structure of the nozzle in the embodiment of the present invention;

[0026] Figure 4 Schematic diagram of the air outlet of the second cylindrical section in an embodiment of the present invention;

[0027] Figure 5 This is a schematic diagram of the structure of a coal-fired power unit boiler in an embodiment of the present invention;

[0028] In the figure, 1-furnace, 2-flame folding angle, 10-soot blowing structure, 111-first pipe section, 112-second pipe section, 20-gas storage tank, 30-horizontal flue, 40-nozzle, 41-first conical section, 42-first cylindrical section, 43-second conical section, 44-second cylindrical section, 441-air outlet, 50-first pipeline, 60-second pipeline, 70-metal hose, 80-electric valve, 90-ball valve, 100-stop valve, 110-pressure gauge, 120-filter, 130-check valve. DETAILED DESCRIPTION

[0029] The following description provides many different embodiments or examples for implementing different features of the present invention. The components and arrangements described in the following specific examples are only used to simplify the present invention and are only used as examples, not to limit the present invention.

[0030] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] The coal-fired power unit boiler comprises a boiler, a furnace 1 and a horizontal flue 30. The flue gas after combustion in the boiler enters the horizontal flue 30 through the furnace 1 and is discharged. The flame deflection angle 2 is a triangular protrusion extending from the upper part of the rear wall of the boiler combustion chamber to the furnace 1.

[0032] This embodiment provides a soot blowing system suitable for the soot accumulation area of ​​the horizontal flue 30, such as Figure 1 , Figure 2 As shown, it includes multiple groups of soot blowing structures 10 and air storage tanks 20, and the gas outlet ends of the air storage tanks 20 are respectively connected to the multiple groups of soot blowing structures 10, and one end of the multiple soot outlet structures are arranged outside the horizontal flue 30 and connected to the gas outlet end of the air storage tank 20; the other end is arranged in the horizontal flue 30 and located at the flame folding angle 2 of the horizontal flue 30; the multiple soot blowing structures 10 located at the flame folding angle 2 of the horizontal flue 30 are provided with multiple spray holes.

[0033] like Figure 5 As shown in the figure, the furnace 1 vertically transports flue gas to the horizontal flue 30, and the flame bending angle 2 is located in the furnace 1; since the soot blowing structure 10 is to be set in the horizontal flue 30, it is also necessary to ensure that it is located at the flame bending angle 2 of the horizontal flue 30, so the setting position of the soot blowing structure 10 is the dotted line in the figure. The soot blowing structure 10 is punched through the left and right walls of the flame bending angle 2, and the flame bending angle 2 is connected to the horizontal flue 30, as shown in the figure. Figure 2 As shown, the first pipe section 111 is located outside the horizontal flue 30, and the second pipe section 112 is located inside the horizontal flue 30. The bottom of the horizontal flue 30 is a plurality of heating surface pipes, and the plurality of heating surface pipes are connected by fins; a supporting structure is welded on the fins to fix the soot blowing structure 10. The soot blowing structure 10 mainly acts on the ash accumulation on the plurality of heating surface pipes of the horizontal flue 30. Due to the ash accumulation, the surfaces of the plurality of heating surface pipes will be horizontal; the ash accumulation on the horizontal surface of the horizontal flue 30 is raised by the kinetic energy of the compressed air under high load. The flue gas flow rate is high under high load, and the fly ash is taken away, thereby alleviating the ash accumulation in the horizontal flue 30.

[0034] It should be noted that the present invention does not limit the specific arrangement of the multiple groups of sootblowing structures 10 at the flame folding angle 2 of the nozzle horizontal flue 30. As long as multiple groups of sootblowing structures 10 are arranged at the flame folding angle 2, compressed air can be ejected in multiple directions; therefore, as long as the sootblowing system has multiple groups of sootblowing structures 10 at the flame folding angle 2, it should be within the protection scope of the present invention.

[0035] In order to reduce the cost of the soot blowing system while ensuring good soot blowing efficiency; it is preferred that Figure 1 , Figure 2 As shown, the soot blowing structures 10 are provided in four groups. Of course, it should be noted that other numbers of soot blowing structures 10 should also be within the protection scope of the present invention.

[0036] In some embodiments, Figure 2 As shown, the soot blowing structure 10 includes a first pipe section 111 and a second pipe section 112, wherein the first pipe section 111 is located outside the horizontal flue 30, and the second pipe section 112 is located inside the horizontal flue 30; one end of the first pipe section 111 is used to connect to the gas outlet end of the gas storage tank 20, and the other end is connected to one end of the second pipe section 112, a valve is provided on the first pipe section 111, and a plurality of the spray holes are provided on the second pipe section 112. With such a structure, each soot blowing structure 10 can be controlled individually, and different use states of the plurality of soot blowing structures 10 can be ensured, such as synchronous blowing of each soot blowing structure 10, asynchronous blowing of each soot blowing structure 10, equal gas volume of each soot blowing structure 10, unequal gas volume of each soot blowing structure 10, etc.; it has the advantages of improving soot blowing efficiency and reducing costs.

[0037] It should be noted that the above-mentioned soot blowing structure 10 is only a preferred mode and does not represent a limitation to the present invention, and the structure of the soot blowing structure 10 without a separate valve should also be within the protection scope of the present invention.

[0038] In some embodiments, Figure 2 As shown, the valve includes a ball valve 90 and an electric valve 80 .

[0039] In some embodiments, a metal hose 70 is disposed at one end of the first pipe section 111 close to the second pipe section 112 , so as to facilitate the movement of the first pipe section 111 and to facilitate the connection with the gas storage tank 20 .

[0040] In some embodiments, Figure 1 As shown, the plurality of spray holes are linearly arranged on the second pipe section 112. Such a structure is simpler and easier to manufacture.

[0041] In some embodiments, Figure 2 As shown, the second pipe section 112 includes two parallel pipes, each of which is provided with a plurality of the spray holes. This has the advantage of increasing the high-pressure air sprayed on the horizontal plane of the horizontal flue 30, and further improving the soot blowing efficiency. Preferably, as Figure 2 As shown, multiple spray holes on two parallel pipes are arranged in an array staggered manner, thereby increasing the soot blowing coverage area and improving the soot blowing efficiency.

[0042] Preferably, there are several heating surface pipes at the bottom of the horizontal flue 30, and the soot-blowing air jet is inclined at a 3° angle to the plane of the heating surface pipes at the bottom of the horizontal flue 30. Setting such an inclination angle can avoid damaging the heating surface pipes, thereby increasing the service life of the horizontal flue 30.

[0043] Furthermore, if Figure 2The two pipes are arranged in parallel, and each pipe is provided with two spray holes. The two spray holes on one pipe are staggered with the two spray holes on the other pipe.

[0044] Specifically, the staggered setting should be understood as: Figure 2 Described, two parallel pipes are arranged in parallel, the spray holes on the left pipe correspond to the interval between two adjacent spray holes on the right pipe, and the spray holes on the right pipe correspond to the interval between two adjacent spray holes on the left pipe.

[0045] In order to further improve the soot blowing efficiency, a plurality of soot blowing structures 10 are evenly arranged in the soot blowing pipe 10; specifically, Figure 2 As shown, two soot blowing structures 10 form a group, and the two groups of soot blowing structures 10 are symmetrically arranged. The evenly arranged soot blowing structures 10 have the advantage of further improving the soot blowing efficiency. It should be noted that Figure 2 The configuration in the embodiment is merely exemplary and does not constitute a limitation to the present invention.

[0046] In some embodiments, a nozzle 40 is provided on the nozzle hole. Figure 3 As shown, the nozzle 40 includes a first conical section 41, a first cylindrical section 42, a second conical section 43 and a second cylindrical section 44. The end of the first conical section 41 with a larger diameter is for air intake, the end of the first conical section 41 with a smaller diameter is connected to one end of the first cylindrical section 42, the other end of the first cylindrical section 42 is connected to the end of the second conical section 43 with a smaller diameter, the end of the second conical section 43 with a larger diameter is connected to one end of the second cylindrical section 44, and the other end of the second cylindrical section 44 is for air discharge. Such a nozzle has the effect of increasing the disturbance of the airflow, and effectively reduces the blowing damage to the horizontal flue 30.

[0047] In some embodiments, Figure 4 As shown, the outlet end of the second cylindrical section 44 is provided with a plurality of outlet holes 441, and the second cylindrical section 44 ejects high-pressure air through the outlet holes 441. Preferably, each of the outlet holes 441 is connected to a spiral outlet pipe (not shown in the figure), and the spiral outlet pipe is arranged in the second cylindrical section 44. The high-pressure air enters the spiral outlet pipe after passing through the second conical section 43, and then ejects through the outlet holes 441.

[0048] In some embodiments, Figure 1 As shown, the air outlet end of the air storage tank 20 is connected to a plurality of soot blowing structures 10 through a first pipeline 50. This ensures that the flow rate and pressure of compressed air provided by the air storage tank 20 to each soot blowing structure 10 are the same; each soot blowing structure controls the flow rate and pressure of compressed air individually through a valve; this reduces the complexity of soot blowing structure control.

[0049] In some embodiments, Figure 1 As shown, a stop valve 100 and a pressure gauge 110 are sequentially arranged on the first pipeline 50 along the gas flow direction; the pressure of the compressed gas coming out of the gas storage tank 20 is controlled by the cooperation of the stop valve 100 and the pressure gauge 110, thereby improving the soot blowing efficiency.

[0050] In some embodiments, the air inlet end of the air storage tank 20 is connected to a second pipe 60. The second pipe 60 is connected to an electric field air source, and compressed air is filled into the air storage tank 20 through the electric field air source.

[0051] In some embodiments, a filter 120 , a check valve 130 , and a stop valve 100 are sequentially disposed on the second pipeline 60 along the gas flow direction.

[0052] The present invention can facilitate automatic control through a soot blowing strategy by arranging an electric valve 80, a ball valve 90, a stop valve 100, a pressure gauge 110, a filter 120, a check valve 130, etc.

[0053] In the present invention, the sootblowing system is only put into operation under a high load of 75%. When the unit runs continuously for more than 6 hours at a load of 40% or less, the system needs to be put into operation at a high load of 75% or more. The operation time of a single sootblower is 60s, and they are put into operation in sequence. The operation time of the entire system is determined according to the number of sootblowers, and the sootblowing pressure is controlled at 0.3-0.5MPa.

[0054] In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise clearly and specifically defined.

[0055] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of multiple components or the interaction relationship of multiple components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0056] In the description of the present invention, it should be understood that all terms used to indicate orientation or positional relationships are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and should not be understood as a limitation on the present invention.

[0057] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A soot blowing system suitable for the soot accumulation area of ​​a horizontal flue, characterized in that: It comprises a plurality of groups of sootblowing structures (10) and an air storage tank (20), wherein the air outlet ends of the air storage tanks (20) are respectively connected to the plurality of groups of sootblowing structures (10), one end of the plurality of sootblowing structures (10) is arranged outside a horizontal flue (30) and connected to the air outlet end of the air storage tank (20); the other end is arranged inside the horizontal flue (30) and located at the flame folding angle of the horizontal flue (30); each of the sootblowing structures (10) located at the flame folding angle of the horizontal flue (30) is provided with a plurality of spray holes.

2. A soot blowing system suitable for the soot accumulation area of ​​a horizontal flue according to claim 1, characterized in that: The sootblowing structure (10) comprises a first pipe section (111) and a second pipe section (112); the first pipe section (111) is located outside the horizontal flue (30), and the second pipe section (112) is located inside the horizontal flue (30); one end of the first pipe section (111) is used to connect to the gas outlet end of the gas storage tank (20), and the other end is connected to one end of the second pipe section (112); a valve is provided on the first pipe section (111), and a plurality of spray holes are provided on the second pipe section (112).

3. A soot blowing system suitable for the soot accumulation area of ​​a horizontal flue according to claim 2, characterized in that: The second pipe section (112) comprises two parallel pipes, and each pipe is provided with a plurality of the spray holes.

4. A soot blowing system suitable for the soot accumulation area of ​​a horizontal flue according to claim 3, characterized in that: The two pipelines are arranged in parallel, and two spray holes are arranged on each pipeline. The two spray holes on one pipeline are arranged in a staggered manner with the two spray holes on the other pipeline.

5. A soot blowing system suitable for the soot accumulation area of ​​a horizontal flue according to claim 2, characterized in that: The valves include ball valves and electric valves.

6. A soot blowing system suitable for the soot accumulation area of ​​a horizontal flue according to any one of claims 1 to 5, characterized in that: The spray hole is provided with a spray pipe (40), and the spray pipe (40) comprises a first conical section (41), a first cylindrical section (42), a second conical section (43) and a second cylindrical section (44); the end of the first conical section (41) with a larger diameter is for air intake, the end of the first conical section (41) with a smaller diameter is connected to one end of the first cylindrical section (42), the other end of the first cylindrical section (42) is connected to the end of the second conical section (43) with a smaller diameter, the end of the second conical section (43) with a larger diameter is connected to one end of the second cylindrical section (44), and the other end of the second cylindrical section (44) is for air discharge.

7. A soot blowing system suitable for the soot accumulation area of ​​a horizontal flue according to claim 1, characterized in that: The gas outlet end of the gas storage tank (20) is in communication with a plurality of soot blowing structures (10) via a first pipeline (50).

8. A soot blowing system suitable for the soot accumulation area of ​​a horizontal flue according to claim 7, characterized in that: A stop valve (100) and a pressure gauge (110) are sequentially arranged on the first pipeline (50) along the gas flow direction.

9. A soot blowing system suitable for the soot accumulation area of ​​a horizontal flue according to claim 1, characterized in that: The air inlet end of the air storage tank (20) is connected to a second pipeline (60).

10. A soot blowing system suitable for the soot accumulation area of ​​a horizontal flue according to claim 9, characterized in that: A filter (120), a check valve (130) and a stop valve (100) are sequentially arranged on the second pipeline (60) along the gas flow direction.

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