A real-time automatic pressure regulating and flow guiding device for secondary air box and an octagonal double tangential circle pulverized coal boiler

Abstract

The present invention discloses a real-time automatic adjustment and diversion device for the secondary air box pressure and an octagonal double tangential circle pulverized coal boiler. The main technical solution adopted is as follows: a front blade assembly, which includes at least one front blade, a first rotary linkage mechanism connected to at least one front blade and installed on both sides of the flue, and a first electric actuator connected to the first rotary linkage mechanism and used to drive the first rotary linkage mechanism to move and drive at least one front blade to rotate clockwise by a certain angle; a rear blade assembly, which includes at least one rear blade, a second rotary linkage mechanism connected to at least one rear blade and installed on both sides of the flue, and a second electric actuator connected to the second rotary linkage mechanism and used to drive the second rotary linkage mechanism to move and drive at least one rear blade to rotate clockwise by a certain angle; at least one fixed blade, which is arranged between at least one front blade and at least one rear blade; a DCS control module.

Description

Technical Field

[0001] The invention relates to the technical field of pulverized coal boilers, and in particular to a secondary wind box pressure real-time automatic adjustment flow guide device and an octagonal double-tangential pulverized coal boiler. Background Art

[0002] The momentum ratio of primary and secondary air in large-scale power station pulverized coal boilers has a certain regulating effect on the size of the actual tangential circle in the furnace and the center of the furnace flame. In addition, different secondary air distribution methods are favorable auxiliary means to avoid coking on the heating surface of the boiler and adjust the steam temperature. Many functions of secondary air are based on a certain secondary air rigidity. In actual operation, the secondary air rigidity is manifested as the differential pressure of the secondary wind box. For the four-corner tangential boiler, the air inlets of the large wind boxes on both sides are arranged symmetrically, and the structural dimensions are consistent. Therefore, the resistance is equal and there is no problem of unbalanced wind box pressure. However, for the octagonal double tangential boiler, it is divided into four wind boxes, and the parameters such as the structural dimensions of the air inlet are inconsistent. Although the design tries to ensure the consistency of resistance, there is still a large deviation in the pressure of the front and rear wall wind boxes in actual operation, which seriously affects the organization of combustion in the furnace and may cause unfavorable conditions such as partial burning and coking.

[0003] At present, different along-the-way and local resistances are designed according to the length of the flue during the design phase, theoretically ensuring that the pressure of the front and rear wall bellows is consistent. However, the frequent changes in actual operating loads lead to frequent changes in smoke velocity, and the fixed duct structure size cannot meet the matching requirements of the flue resistance characteristics under all operating conditions, so it is impossible to adjust the bellows pressure under all operating conditions. At present, the bellows pressure is adjusted by adding an adjustment baffle to each bellows inlet duct. Due to the constraints of factors such as the flue structure size, it is impossible to achieve fine adjustment, and the baffle with a small opening increases the local resistance of the system, resulting in an increase in the power consumption of the fan, affecting the economic operation of the unit. Therefore, there is still a lack of effective means for accurate and real-time automatic adjustment of the secondary bellows pressure of coal-fired octagonal double-cut circle boilers in large power stations. Summary of the invention

[0004] In view of this, the present invention provides a secondary wind box pressure real-time automatic adjustment guide device and an octagonal double-cut circle pulverized coal boiler, the main purpose of which is to solve the problem that the octagonal double-cut circle pulverized coal boiler cannot achieve fine adjustment of the secondary wind box pressure.

[0005] In order to achieve the above object, the present invention mainly provides the following technical solutions:

[0006] On the one hand, an embodiment of the present invention provides a secondary air box pressure real-time automatic adjustment flow guide device. It includes:

[0007] The front vane assembly includes at least one front vane, a first rotary linkage mechanism connected to the at least one front vane and installed on both sides of the flue, and a first electric actuator connected to the first rotary linkage mechanism and used to drive the first rotary linkage mechanism to move and drive the at least one front vane to rotate clockwise by a certain angle.

[0008] The rear vane assembly includes at least one rear vane, a second rotary linkage mechanism connected to the at least one rear vane and installed on both sides of the flue, and a second electric actuator connected to the second rotary linkage mechanism and used to drive the second rotary linkage mechanism to move and drive the at least one rear vane to rotate clockwise by a certain angle.

[0009] At least one fixed vane is disposed between the at least one front vane and the at least one rear vane and is not connected to the at least one front vane and the at least one rear vane.

[0010] The DCS control module is used to control the operation of the first electric actuator to drive the first rotary linkage mechanism to move and to control the operation of the second electric actuator to drive the second rotary linkage mechanism to move.

[0011] As described above, preferably, there are 2 front vanes and 2 rear vanes.

[0012] As described above, the range of the clockwise rotation angle of the at least one front vane and the at least one rear vane is -15° to +15°.

[0013] As described above, the magnitude of the clockwise rotation angle of the at least one front vane and the at least one rear vane is adjusted within the range of -15° to +15° according to the load of the octagonal double-tangent circle pulverized coal boiler.

[0014] As described above, the first rotary linkage mechanism includes at least one first fixed shaft connected to the at least one front vane, a connecting rod connected to the at least one first fixed shaft, and a first transmission mechanism respectively connected to the connecting rod and the first electric actuator. The at least one first fixed shaft is installed and fixed on both sides of the flue through a first sealed hinge, and the front vane can rotate clockwise by a certain angle around the first fixed shaft.

[0015] As described above, the second linkage mechanism includes at least one second fixed shaft connected to the at least one rear vane, a connecting rod connected to the at least one second fixed shaft, and a second transmission mechanism respectively connected to the connecting rod and the second electric actuator. The at least one second fixed shaft is fixedly installed on both sides of the flue through a second sealed hinge, and the rear vane can rotate clockwise by a certain angle around the second fixed shaft.

[0016] As described above, both the first electric actuator and the second electric actuator are installed and fixed on the outer frame of the hot secondary air duct of the octagonal double tangential circle pulverized coal boiler.

[0017] As described above, the control device is a unit DCS control module, which includes an input button and an output button.

[0018] On the other hand, an embodiment of the present invention further provides an octagonal double tangential circle pulverized coal boiler. It includes:

[0019] A boiler body;

[0020] Four wind boxes, respectively arranged on the front and rear walls of the boiler body;

[0021] Multiple at least one-layer secondary air box pressure regulating and guiding devices, which are respectively and evenly arranged in the inlet air ducts of the four wind boxes.

[0022] As described above, multiple two-layer secondary air box pressure regulating and guiding devices are respectively and evenly arranged in the inlet air ducts of the four wind boxes.

[0023] By means of the above technical solutions, the present invention has at least the following advantages:

[0024] The secondary air box pressure real-time automatic regulating and guiding device and the octagonal double tangential circle pulverized coal boiler of the present invention are provided with a front vane assembly, a rear vane assembly, fixed vanes and a DCS control module. The DCS control module controls the first electric actuator to work, drives the first rotating linkage mechanism to move, drives the at least one front vane to rotate clockwise by a certain angle, and the DCS control module controls the second electric actuator to work, drives the second rotating linkage mechanism to move, drives the at least one rear vane to rotate clockwise by a certain angle, so that the front vane and the rear vane can be adjusted at any time according to the load size of the octagonal double tangential circle pulverized coal boiler, to ensure the uniformity of the resistance of the inlet air ducts of the front and rear walls under different loads, that is, different air supply volumes, and realize the dynamic uniform distribution adjustment and refined automatic adjustment of the secondary air box pressure.

[0025] The above description is only an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and be implemented in accordance with the content of the specification, the following will be described in detail with reference to the preferred embodiments of the present invention and the accompanying drawings. Description of the Drawings

[0026] Figure 1 It is a schematic structural diagram of the real-time automatic adjustment and diversion device for the secondary air box pressure of the present invention;

[0027] Figure 2 It is a schematic structural diagram of at least one front blade, at least one rear blade and at least one fixed blade of the present invention;

[0028] Figure 3 It is a schematic diagram of the installation position I of the real-time automatic adjustment and diversion device for the secondary air box pressure of the present invention;

[0029] Figure 4 It is a schematic diagram of the installation position II of the real-time automatic adjustment and diversion device for the secondary air box pressure of the present invention;

[0030] Figure 5 It is an automatic adjustment curve graph of the front blade and the rear blade of the present invention. Detailed Description of the Invention

[0031] In order to further elaborate on the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following will be described in detail with reference to the accompanying drawings and preferred embodiments regarding the specific implementation manners, structures, features and their effects of the application according to the present invention.

[0032] As Figure 1 shown, a real-time automatic adjustment and diversion device 1 for the secondary air box pressure proposed in an embodiment of the present invention includes: a front blade assembly 11, a rear blade assembly 12, a fixed blade 13 and a DCS control module.

[0033] As Figures 1 to 4As shown in the figure, the front blade assembly 11 includes at least one front blade 111, a first rotation linkage mechanism 112 connected to the at least one front blade 111 and installed on both sides of the air box inlet air duct 2, and a first electric actuator 113 connected to the first rotation linkage mechanism 112 and used to drive the first rotation linkage mechanism 112 to move and drive the at least one front blade 111 to rotate clockwise by a certain angle. Preferably, there are generally 2 front blades 111. The first rotation linkage mechanism 112 includes at least one first fixed shaft 1121 connected to the at least one front blade 111, a connecting rod 1122 connected to the at least one first fixed shaft 1121, and a first transmission mechanism respectively connected to the connecting rod 1122 and the first electric actuator 113. The at least one first fixed shaft 1121 is installed and fixed on both sides of the air box inlet air duct 2 through a first sealed hinge. The front blade 111 can rotate clockwise by a certain angle around the first fixed shaft 1121. The range of the clockwise rotation angle of at least one front blade 111 with the first fixed shaft 1121 as the origin is -15° to +15°. The first electric actuator 113 is erected and fixed on the outer frame of the hot secondary air duct of the octagonal double tangential circle pulverized coal boiler.

[0034] As Figures 1 to 4 shown in the figure, the rear blade assembly 12 includes at least one rear blade 121, a second rotation linkage mechanism 122 connected to the at least one rear blade 121 and installed on both sides of the air box inlet air duct 2, and a second electric actuator 123 connected to the second rotation linkage mechanism 122 and used to drive the second rotation linkage mechanism 122 to move and drive the at least one rear blade 121 to rotate clockwise by a certain angle. Preferably, there are generally 2 rear blades. The second rotation linkage mechanism 122 includes at least one second fixed shaft 1221 connected to the at least one rear blade 121, a connecting rod 1222 connected to the at least one second fixed shaft 1221, and a second transmission mechanism 1223 respectively connected to the connecting rod 1222 and the second electric actuator 1222. The at least one second fixed shaft 1221 is installed and fixed on both sides of the air box inlet air duct 2 through a second sealed hinge. The rear blade 121 can rotate clockwise by a certain angle around the second fixed shaft 1221. The range of the clockwise rotation angle of the at least one rear blade 121 with the second fixed shaft 1221 as the origin is -15° to +15°. The second electric actuator 123 is erected and fixed on the outer frame of the hot secondary air duct of the octagonal double tangential circle pulverized coal boiler.

[0035] As Figure 1 and Figure 2As shown, the at least one fixed vane 13 is disposed between the at least one front vane 111 and the at least one rear vane 121 and is not connected to the at least one front vane 111 and the at least one rear vane 121. Preferably, there are generally two fixed vanes 3, and one fixed vane 13 is located between one front vane 111 and one rear vane 121.

[0036] The DCS control module is used to control the operation of the first electric actuator 113 to drive the movement of the first rotary linkage mechanism 112 and to control the operation of the second electric actuator 123 to drive the movement of the second rotary linkage mechanism 122. The control circuits of the first electric actuator 113 and the second electric actuator 123 are introduced into the unit DCS control module, and can be remotely controlled by the operator in the DCS control module. An automatic control loop is built in the DCS control module. According to the rotation angles of the at least one front vane 111 and the at least one rear vane 121 within the range of -15° to +15° and the load of the octagonal double tangential circle pulverized coal boiler, a flue gas flow equalization automatic adjustment curve is formulated, as Figure 5 As shown, it is a graph of the boiler output (rated output percentage) of the octagonal double tangential circle pulverized coal boiler with the front vane 111 and the rear vane 121. Among them, the solid line is the rotation angle adjustment curve of the front vane 111, and the dashed line is the rotation angle adjustment curve of the rear vane 121. When the octagonal double tangential circle pulverized coal boiler is operating, the rotation angles of the at least one front vane 111 and the at least one rear vane 121 can be automatically adjusted clockwise within the range of -15° to +15° according to this curve to ensure the uniformity of the inlet duct resistance of the front and rear walls at different loads, that is, different air supply volumes, realizing the dynamic uniform adjustment of the secondary air box pressure and the refined automatic adjustment of the front and rear wall air box pressures. An automatic adjustment control loop is built in the DCS control module. From the graph of the front vane 111 and the rear vane 121 and the output of the octagonal double tangential circle pulverized coal boiler, it can be seen that the rotation angles of the front vane 111 and the rear vane 121 change linearly with the output of the octagonal double tangential circle pulverized coal boiler; when the load of the octagonal double tangential circle pulverized coal boiler is small, the distribution of the air flow is more uniform, then the smaller the rotation angle of the front vane 111 is adjusted, and the larger the rotation angle of the rear vane 121 is adjusted, and the linear shape of the real-time automatic adjustment and diversion device 1 of the secondary air box pressure is straighter; when the load of the octagonal double tangential circle pulverized coal boiler is high, the distribution of the air flow is more uneven, then the larger the rotation angle of the front vane 111 is adjusted, and the smaller the rotation angle of the rear vane 121 is adjusted, and the linear shape of the real-time automatic adjustment and diversion device 1 of the secondary air box pressure is more curved. The on and off buttons for building the automatic adjustment control loop in the DCS can put the automatic adjustment function into or out of service at any time.

[0037] The real-time automatic regulation and diversion device for the secondary air box pressure in the embodiment of the present invention is provided with a front blade assembly, a rear blade assembly, fixed blades and a DCS control module. The DCS control module controls the first electric actuator to drive the first rotating linkage mechanism to drive at least one front blade to rotate clockwise by a certain angle. The DCS control module controls the second electric actuator to drive the second rotating linkage mechanism to drive at least one rear blade to rotate clockwise by a certain angle, so that the front blades and the rear blades can be adjusted at any time according to the load of the octagonal double tangential circle pulverized coal boiler, so as to ensure the uniformity of the resistance of the inlet air ducts on the front and rear walls under different loads, that is, different air supply volumes, and realize the dynamic uniform distribution adjustment and refined automatic regulation of the secondary air box pressure.

[0038] As Figure 3 and Figure 4 shown, on the other hand, the embodiment of the present invention also provides an octagonal double tangential circle pulverized coal boiler. It includes: a boiler body 3, four air boxes 4 and a plurality of at least one layer of secondary air box pressure regulation and diversion devices 1.

[0039] The four air boxes 4 are respectively arranged on the front and rear walls of the boiler body 3; the plurality of at least one layer of secondary air box pressure regulation and diversion devices 1 are respectively and uniformly arranged in the inlet air ducts 2 of the four air boxes 4. Preferably, generally, a plurality of two-layer secondary air box pressure regulation and diversion devices 1 are respectively and uniformly arranged in the inlet air ducts 2 of the four air boxes 4.

[0040] The octagonal double tangential circle pulverized coal boiler in the embodiment of the present invention is provided with a plurality of at least one layer of secondary air box pressure regulation and diversion devices 1, which are respectively and uniformly arranged in the inlet air ducts 2 of the four air boxes 4, so that the front blades and the rear blades can be adjusted at any time according to the load of the octagonal double tangential circle pulverized coal boiler, so as to ensure the uniformity of the resistance of the inlet air ducts on the front and rear walls under different loads, that is, different air supply volumes, and realize the dynamic uniform distribution adjustment and refined automatic regulation of the secondary air box pressure of the octagonal double tangential circle pulverized coal boiler.

[0041] The above is only a preferred embodiment of the present invention, and does not impose any form of limitation on the present invention. Any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A real-time automatic pressure regulating and guiding device for a secondary air box, which is used for an octagonal double tangential circle pulverized coal boiler, characterized in that: it includes: A front blade assembly, which includes at least one front blade, a first rotating linkage mechanism connected to the at least one front blade and installed on both sides of the air box inlet duct, and a first electric actuator connected to the first rotating linkage mechanism and used to drive the first rotating linkage mechanism to drive the at least one front blade to rotate clockwise by a certain angle; A rear blade assembly, which includes at least one rear blade, a second rotating linkage mechanism connected to the at least one rear blade and installed on both sides of the air box inlet duct, and a second electric actuator connected to the second rotating linkage mechanism and used to drive the second rotating linkage mechanism to drive the at least one rear blade to rotate clockwise by a certain angle; At least one fixed blade, which is arranged between the at least one front blade and the at least one rear blade and is not connected to the at least one front blade and the at least one rear blade; A DCS control module, which is used to control the first electric actuator to drive the first rotating linkage mechanism to move and to control the second electric actuator to drive the second rotating linkage mechanism to move; The first rotating linkage mechanism includes at least one first fixed shaft connected to the at least one front blade, a connecting rod connected to the at least one first fixed shaft, and a first transmission mechanism respectively connected to the connecting rod and the first electric actuator. The at least one first fixed shaft is installed and fixed on both sides of the air box inlet duct through a first sealing hinge, and the front blade can rotate clockwise by a certain angle around the first fixed shaft; The second rotating linkage mechanism includes at least one second fixed shaft connected to the at least one rear blade, a connecting rod connected to the at least one second fixed shaft, and a second transmission mechanism respectively connected to the connecting rod and the second electric actuator. The at least one second fixed shaft is installed and fixed on both sides of the air box inlet duct through a second sealing hinge, and the rear blade can rotate clockwise by a certain angle around the second fixed shaft.

2. The real-time automatic pressure regulating and guiding device for a secondary air box according to claim 1, characterized in that, both the front blade and the rear blade are two.

3. The real-time automatic pressure regulating and guiding device for a secondary air box according to claim 1, characterized in that, the range of the clockwise rotation angle of the at least one front blade and the at least one rear blade is -15° to +15°.

4. The real-time automatic pressure regulating and guiding device for a secondary air box according to claim 3, characterized in that, the magnitude of the clockwise rotation angle of the at least one front blade and the at least one rear blade is adjusted within the range of -15° to +15° according to the load of the octagonal double tangential circle pulverized coal boiler.

5. The real-time automatic pressure regulating and guiding device for a secondary air box according to claim 1, characterized in that, Both the first electric actuator and the second electric actuator are installed and fixed on the outer frame of the hot secondary air duct of the octagonal double tangential circle pulverized coal boiler.

6. The real-time automatic regulating and guiding device for the secondary air box pressure according to claim 1, characterized in that, the control device is a unit DCS control module, which includes an input button and an output button.

7. An octagonal double tangential circle pulverized coal boiler, characterized in that, it includes: a boiler body; four air boxes, which are respectively arranged on the front and rear walls of the boiler body; a plurality of at least one layer of real-time automatic regulating and guiding devices for the secondary air box pressure as described in any one of claims 1-6, which are respectively and evenly arranged in the inlet air ducts of the four air boxes.

8. The octagonal double tangential circle pulverized coal boiler according to claim 7, characterized in that, a plurality of two-layer real-time automatic regulating and guiding devices for the secondary air box pressure are respectively and evenly arranged in the inlet air ducts of the four air boxes.

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