CN204268500U - Coal pulverizer outlet rapid closing device and mill coal pulverizer system - Google Patents

Abstract

A coal mill outlet quick-closing device and a coal mill pulverization system, the coal mill outlet quick-closing device includes: a rectangular sealed box body, which is welded between two sections of powder conveying pipelines through two bottom surfaces; two first sealing plates , arranged on two opposite sides of the rectangular sealed box; the baffle mechanism is composed of a plurality of baffles and a plurality of rotating shafts, and the two ends of the plurality of rotating shafts are respectively fixed in parallel on the other two opposite sides of the rectangular sealed box and the first sealing plate and the rotating shaft are in the same plane; along the direction of the rotating shaft, one side of the upper bottom surface of each baffle plate and the opposite side of the lower bottom surface respectively have an L-shaped gap; the transmission mechanism and the plurality of rotating shafts respectively Connection; driving device, connected to the transmission mechanism; ring-shaped sealed air duct, set on the outer side of the rectangular sealed box, the outer side of the annular sealed air duct is provided with a sealed air inlet, and the inner surface of the annular sealed air duct is provided with multiple sealed air inlets , the sealing air inlet introduces the sealing air into the rectangular sealed box body.

Description

Coal Mill Exit Speed Closing Device and Coal Mill Pulverization System

technical field

The utility model relates to the pulverizing system technology in an electric boiler, in particular to a coal mill outlet quick-closing device and a coal pulverizing system.

Background technique

In the power plant boiler of the positive pressure direct blowing pulverizing system, a certain number of pulverizer pipes are connected between the outlet of the pulverizer and the burner. Generally, a single pulverizer of a four-corner tangential boiler is equipped with four pulverizer pipes, and the front and rear walls The single pulverizer of the opposed combustion boiler is equipped with 4-6 powder conveying pipes. According to the direction of the airflow, the coal mill outlet speed closing device, resistance adjusting device (shrinkage cavity), pulverized coal sampling device, wind speed measuring device, etc. are generally installed in sequence on the powder conveying pipeline.

The quick-closing device at the exit of the coal mill is controlled by a pneumatic actuator, and the baffle is a plug-in door, which can quickly close and cut off the fuel in the case of a coal mill tripping accident, and can also close the exit door when the coal mill is out of operation normally. It is used to close the coal mill and cut off the air powder conveying channel.

Due to the different lengths and orientations of the powder delivery pipes at the outlet of the coal mill, there are large differences in the internal flow resistance of the air-powder mixture. Usually, resistance devices such as throttling devices are installed on the powder delivery pipelines to adjust the flow of the powder delivery pipelines. The flow resistance of the air powder airflow makes the wind speed and air powder concentration at the burner nozzle corresponding to the same coal mill uniform.

The outlet door and resistance adjustment device are installed on the pulverized conveying pipeline of the existing power station boiler coal mill, but they are basically installed separately. The outlet door is a sliding door (number 1 in Figure 1), and generally a pneumatic control door is used. It is used to close the connection between the pulverizer outlet powder delivery pipeline and the furnace burner; the adjustment of the resistance throttling device (mark 2 in Figure 1) is mainly a manual adjustable device, and a few boilers are equipped with fixed throttling devices. The flow shrinkage hole, through the preset throttling resistance, adjusts the speed of the air powder mixture passing through the device. The outlet door and throttling device are separately installed and arranged on the pulverizing system as shown in Figure 1. In Figure 1, 1 is the exit door, 2 is the resistance adjustment device, 3 is the wind speed or pulverized coal concentration test device, 4 is the hot air adjustment baffle at the coal mill inlet, 5 is the cold air adjustment baffle at the coal mill inlet, and 6 is the mill The main damper at the entrance of the coal machine, 7 is the air volume measuring device at the entrance of the coal mill.

The pulverized pipeline between the outlet of the coal mill and the burner is limited by the layout and length of the pipeline, and the installation position of the outlet door and the resistance adjustment device is not ideal, especially the lowest level of the coal mill. The distance between the connected pulverized coal pipelines is short, and there are many elbows in the pulverized coal pipelines. They are arranged separately, and the installation location is very compact, which affects the uniformity of the pulverized coal flow in the pulverized coal pipelines, and brings great difficulties to pulverized coal sampling and wind speed measurement. big error. In addition, the separate arrangement of the exit door and the resistance adjustment device increases the purchase cost of the equipment and the maintenance workload.

Utility model content

The utility model provides a quick-closing device for the outlet of a coal mill and a pulverization system of a coal pulverization mechanism to solve the limitation of the installation position caused by the too short pulverized pipeline and the uneven air flow of pulverized coal caused by it, and the on-site test data inaccurate issues, and reduce costs.

In order to achieve the above purpose, the embodiment of the utility model provides a quick-closing device for the outlet of the coal mill, and the quick-close door for the outlet of the coal mill includes:

A rectangular sealed box body, the rectangular sealed box body is welded between two sections of powder conveying pipelines through two bottom surfaces;

Two first sealing plates are arranged on two opposite sides of the rectangular sealing box;

The baffle mechanism is composed of a plurality of baffles and a plurality of rotating shafts that drive the baffles to rotate. The two ends of the plurality of rotating shafts are respectively fixed in parallel on the other two opposite sides of the rectangular sealed box body, and the first seal The plate and the rotating shaft are in the same plane; along the direction of the rotating shaft, one side of the upper bottom surface of each baffle plate and the opposite side of the lower bottom surface respectively have an L-shaped gap, so that when the baffle plate is closed, the gap between the adjacent baffle plates The gaps between each other cooperate with each other, and the gap of one of the outermost baffles cooperates with the first sealing plate;

The transmission mechanism is respectively connected with multiple rotating shafts;

a driving device, connected to the transmission mechanism, for driving the transmission mechanism;

The annular sealed air duct is set on the outer side of the rectangular sealed box, the outer surface of the annular sealed air duct is provided with a sealed air inlet, and the inner surface of the annular sealed air duct is provided with a plurality of sealed air inlets. The sealing air inlet introduces the sealing air into the rectangular sealing box.

In one embodiment, the quick-closing device for the outlet of the coal mill further includes:

Multiple pairs of second sealing plates are arranged on two opposite sides of the fixed rotating shaft, and are in the same plane as the plurality of rotating shafts, and each pair of second sealing plates is separated on both sides of one end of a rotating shaft, so that When the baffle is closed, each pair of second sealing plates respectively cooperates with the notches on both sides of the baffle.

In one embodiment, the driving device is a pneumatic or electric driving device.

In one embodiment, the number of the baffle mechanisms is five.

In one embodiment, the rectangular sealed box is a metal box.

In order to achieve the above purpose, an embodiment of the utility model provides a coal pulverization system, the pulverization system includes: a coal pulverizer, a plurality of pulverized coal pipelines connected to the coal pulverizer, arranged in each The wind speed measuring device on the pulverized coal pipeline and the coal mill outlet speed closing device according to claim 1 arranged on each pulverized coal pipeline.

In one embodiment, the quick-closing device for the outlet of the coal mill further includes:

Multiple pairs of second sealing plates are arranged on two opposite sides of the fixed rotating shaft, and are in the same plane as the plurality of rotating shafts, and each pair of second sealing plates is separated on both sides of one end of a rotating shaft, so that When the baffle is closed, each pair of second sealing plates respectively cooperates with the notches on both sides of the baffle.

In one embodiment, the driving device is a pneumatic or electric driving device.

In one embodiment, the number of the baffle mechanisms is five.

In one embodiment, the rectangular sealed box is a metal box.

The beneficial effects of the utility model embodiment are:

The "two-in-one" combination of the traditional coal mill outlet door and the resistance adjustment device can meet the rapid closing and adjustment of the resistance of the pulverized coal pipeline, reduce the equipment installed on the pulverized pipeline, and reduce the workload of maintenance;

After the pulverizing system adopts the coal mill outlet speed-closing device of the utility model, a group of installation parts will be reduced in the pulverized pipeline, which will provide a better and more compliant position for the installation of the wind speed measuring device on the pulverized pipeline to create conditions, and then It effectively solves the problems of poor fluidity of air powder mixture and uneven air flow of air powder caused by too short pulverized coal pipelines and insufficient installation space in most power plant pulverization systems, and better meets the requirements of field tests.

The new device adopts a pneumatic control method, which has the functions of a speed-closing device at the exit of the coal mill and a resistance adjustment function, and can be operated remotely, making it possible to dynamically adjust the resistance of the powder conveying pipeline in random groups, improving the control flexibility of the resistance adjustment device, and improving the combustion efficiency. Create conditions for dynamic and precise control of pulverized coal velocity and concentration at each corner of the process;

The form of multi-blade baffles is adopted, and each blade is adjusted synchronously, avoiding the non-linear and uneven resistance adjustment of the traditional two-piece shrinkage cavity (shown in Figure 1), thereby improving the pulverized coal flow in the pulverized coal pipeline through the resistance adjustment device ( Shrinkage cavity) after flow uniformity, it is beneficial to improve the concentration of pulverized coal, the representativeness and accuracy of pulverized coal airflow sampling, and improve the accuracy of wind speed measurement;

The cold primary air or the existing sealing air is used as the sealing air of the device, which is connected to the annular sealing air duct, which effectively solves the problem of clogging of traditional shrinkage cavities and powder accumulation, and improves the reliability of the device; at the same time, it avoids the blockage of the traditional coal mill outlet speed closing device. Issues with slow or lax closures.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are only some embodiments of the utility model, and those skilled in the art can also obtain other drawings according to these drawings without any creative effort.

Fig. 1 is the structural schematic diagram of existing coal pulverization system;

Fig. 2 is a top view of the quick-closing device at the outlet of the coal mill according to the embodiment of the utility model;

Fig. 3 is a side view of the quick-closing device at the outlet of the coal mill according to the embodiment of the present invention;

Fig. 4 is a schematic diagram of the connection between the rectangular sealed box and the powder delivery pipeline of the embodiment of the present invention;

Fig. 5 is an enlarged view of the baffle plate and the first sealing plate in Fig. 3 of the embodiment of the present invention;

FIG. 6 is a schematic structural view of multiple pairs of second sealing plates 20 according to an embodiment of the present invention;

7 and 8 are schematic diagrams of the state of the second sealing plate 20 according to the embodiment of the present invention;

Fig. 9 is a schematic structural diagram of the coal pulverization system of the embodiment of the utility model.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. example. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

As shown in Fig. 2 and Fig. 3, the utility model provides a quick-closing device for the outlet of the coal mill. The quick-closing device for the outlet of the coal mill includes: a rectangular sealing box 9, two first sealing plates 3, and Plate mechanism, transmission mechanism 6, driving device 7 and annular sealing air duct.

As shown in FIG. 4 , the rectangular sealed box body 9 is welded between two sections 10 of powder delivery pipelines 11 through two bottom surfaces. The two first sealing plates 3 , the baffle mechanism and the transmission mechanism 6 are all arranged inside the rectangular sealed box body 9 , and the driving device 7 is arranged outside the rectangular sealed box body 9 , which is not shown in FIG. 4 .

As shown in FIG. 2 and FIG. 3 , the two first sealing plates 3 are respectively arranged on two opposite sides 12 , 13 of the rectangular sealing box 9 .

The baffle plate mechanism is composed of a plurality of baffle plates 1 and a plurality of rotating shafts 2 that drive the baffle plates to rotate. The two ends of the plurality of rotating shafts 2 are respectively fixed in parallel on the other two opposite sides 14, 15 of the rectangular sealed box body 9, and the two The first sealing plate 3 and the rotating shaft 2 are in the same plane. As shown in Fig. 3 and Fig. 5, along the direction of the rotating shaft, one side 16 of the upper bottom surface of each baffle plate 1 and the opposite side 17 of the lower bottom surface respectively have an L-shaped gap (or called a groove) 18, so that when the baffle plate 1 When the plates 1 are closed, the notches between adjacent baffles can cooperate with each other and the notch of one of the outermost baffles can cooperate with said first sealing plate. When the baffles 1 are closed, the relationship between the baffles is shown in Figure 5. After the adjacent baffles are bonded together, and after the two outermost baffles are bonded to the two first sealing plates 3, the L The shaped gap plays a very good sealing role, which can ensure that the blade baffle can effectively block the passage of airflow after the blade baffle is closed, and realize reliable blocking.

The transmission mechanism 6 is connected to the plurality of rotating shafts 2 respectively. The driving device 7 is connected to the transmission mechanism 6 to drive the transmission mechanism to drive a plurality of rotating shafts 2 to rotate respectively, and finally drive the baffle plate 1 to rotate around the rotating shaft. In one embodiment, the baffle plate 1 is a blade baffle plate. The utility model is not based on This is the limit.

As shown in Figure 2, the annular sealed air duct 4 is set on the outer surface of the rectangular sealed box body 9, the outer surface of the annular sealed air duct 9 is provided with a sealed air inlet 8, and the inner surface of the annular sealed air duct is provided with a plurality of sealing Air inlet 19, sealing air inlet 19 introduces sealing air in the rectangular sealed box body 9. The sealing air enters the annular sealing air duct 4 of the quick-closing device at the exit of the coal mill from the sealing air inlet 8 shown in FIG. 2 . The pressure of the sealing wind is about 2 times of the pressure of the air-powder mixture in the powder delivery pipeline, and can enter the inside of the rectangular sealed box body 9 from multiple directions through a plurality of sealing air inlets 19, and the air is formed by the gap between the blade baffle plate and the powder delivery pipeline. The gap enters the powder conveying pipeline, which plays a role in blocking the pulverized coal from entering the quick-closing device at the exit of the pulverizer, preventing the accumulation of pulverized coal from blocking the blade baffle or the transmission mechanism, and affecting the flexibility of the mechanism adjustment.

From the above analysis, it can be seen that when the air-powder mixture flows through the coal mill outlet speed-closing device of the utility model, the coal mill outlet speed-closing device will produce different system resistances at different opening positions, thereby affecting the air-powder mixture. Flow velocity and pulverized coal concentration. The wind-powder mixture is used in conjunction with the downstream wind speed measuring device (also can be a pulverized coal concentration measuring device) 2, and the wind speed monitored by the device 2 ( Measured by the wind speed measuring device) or pulverized coal concentration (measured by the pulverized coal concentration measuring device), thus achieving the purpose of dynamic adjustment.

When the "coal mill outlet speed closing device receives a closing command, the driving device 7 controls the blade baffle to quickly close to the minimum opening to realize the sealing and isolation of the pulverizer pipeline, thereby realizing the coal mill outlet baffle. Quick shutdown function.

Utilizing the quick-closing device at the outlet of the coal mill of the utility model, the air-powder mixture coming out of the coal mill and entering the powder conveying pipeline only needs to pass through a quick-closing device at the outlet of the coal mill with the function of resistance adjustment, so that various The dynamic adjustment of the flow velocity in the powder conveying pipeline and the shut-off isolation function ensure that the wind speed of the air-powder mixture at each corner is consistent, making the flow field of the air-powder mixture in the powder conveying pipeline more uniform, so that the wind speed measuring device or the pulverized coal concentration measuring device is used for powder conveying. The installation on the pipeline provides a better and more compliant location to create conditions, effectively solving the problems of poor fluidity of the air-powder mixture and uneven airflow of the air-powder mixture caused by too short pulverized coal pipelines and insufficient installation space in most power plant pulverization systems , to better meet the field test requirements.

The above-mentioned coal mill outlet quick-closing device is only equipped with two first sealing plates on the two opposite sides (two sides parallel to the rotating shaft) 12 and 13 on which the rotating shaft 2 is not fixed on the rectangular sealing box body 9 3. The sealing baffles are not fixed on the two opposite sides 14 , 15 of the fixed rotating shaft 2 . In order to make the sealing better, in one embodiment, as shown in FIG. 6 , multiple pairs of second sealing plates 20 are arranged on the two opposite sides 14, 15 of the fixed rotating shaft 2, and multiple pairs of second sealing plates 20 20 and a plurality of rotating shafts 2 are in the same plane, and the two baffles of each pair of second sealing plates are separated on both sides of one end of a rotating shaft, so that when the baffles are closed, each pair of second sealing plates is respectively connected to the corresponding baffle. The notches on both sides of the board fit. Next, with reference to FIG. 7 and FIG. 8 , taking one of the rotating shafts 2 on the side 14 as an example, how to achieve sealing through each pair of second sealing plates 20 will be described. As shown in Figure 7, the fixed rotating shaft 2 on the side 14 rotates, and drives the baffle plate 1 to rotate clockwise, so that the closed state shown in Figure 8 can be obtained, the two baffle plates 21, 22 of the second sealing plate 20 The L-shaped notches 18 of the baffle 1 are respectively filled to achieve better sealing.

The above-mentioned driving device 7 may be a pneumatic or electric driving device, such as an electric motor or a pneumatic motor. The transmission mechanism 6 of the quick-closing device at the outlet of the coal mill is driven by a pneumatic or electric drive device, and can be quickly closed within 3 seconds, meeting the requirements of rapid fuel cut-off in accident conditions or normal outage conditions.

In one embodiment, the number of baffle mechanisms is five, and the present invention is not limited thereto. The blade baffle can be made of wear-resistant alloy, and altogether 5 pieces are enclosed in the rectangular sealed box body (metal shell) 9, and are installed in the pulverized coal pipeline, as shown in Figure 3, the blade is in the transmission device 7 Driven to open and close at the same time, it plays the role of closing the baffle or uniform throttling. The multi-blade baffle structure of the exit speed closing device of the coal mill has more flexible blade movements and uniform resistance adjustment, which can evenly adjust the flow rate and ensure the consistency of the flow field after throttling. In addition, the blade baffle of the quick-closing device at the exit of the coal mill can realize the pneumatic control and adjustment operation within the full-open and full-close range, making it possible to dynamically adjust the resistance of the pulverized coal pipeline system during the normal operation of the pulverized coal pulverized system.

After adopting the quick-closing device at the outlet of the coal mill, a group of installation parts (i.e. canceling 1 and 2 in Figure 1) will be canceled for the powder conveying pipeline of the pulverized coal mill pulverization system, and the original function will be realized by using the quick-closing device at the outlet of the coal mill . Its working process is:

Utilizing the quick-closing device at the outlet of the coal mill of the utility model, the air-powder mixture coming out of the coal mill and entering the powder delivery pipeline only needs to pass through a quick-close door at the outlet of the coal mill with the function of resistance adjustment, so that each delivery can be realized at the same time. The dynamic adjustment of the flow velocity in the powder pipeline and the shut-off isolation function ensure that the wind speed of the air-powder mixture at each corner is consistent, making the flow field of the air-powder mixture in the powder pipeline more uniform, so that the wind speed measurement device or the pulverized coal concentration measurement device is in the powder pipeline. The installation on the ground provides a better and more compliant location to create conditions, effectively solving the problems of poor fluidity of the air-powder mixture and uneven air flow caused by the short pulverized coal pipelines and insufficient installation space of most power plant pulverization systems. Better meet the requirements of on-site testing.

In summary, the beneficial effects of the embodiments of the present invention are:

The "two-in-one" combination of the traditional coal mill outlet door and the resistance adjustment device can meet the rapid closing and adjustment of the resistance of the pulverized coal pipeline, reduce the equipment installed on the pulverized pipeline, and reduce the workload of maintenance;

After the pulverizing system adopts the coal mill outlet speed-closing device of the utility model, a group of installation parts will be reduced in the pulverized pipeline, which will provide a better and more compliant position for the installation of the wind speed measuring device on the pulverized pipeline to create conditions, and then It effectively solves the problems of poor fluidity of air powder mixture and uneven air flow of air powder caused by too short pulverized coal pipelines and insufficient installation space in most power plant pulverization systems, and better meets the requirements of field tests.

The new device adopts a pneumatic control method, which has the functions of a speed-closing device at the exit of the coal mill and a resistance adjustment function, and can be operated remotely, making it possible to dynamically adjust the resistance of the powder conveying pipeline in random groups, improving the control flexibility of the resistance adjustment device, and improving the combustion efficiency. Create conditions for dynamic and precise control of pulverized coal velocity and concentration at each corner of the process;

The form of multi-blade baffles is adopted, and each blade is adjusted synchronously, avoiding the non-linear and uneven resistance adjustment of the traditional two-piece shrinkage cavity (shown in Figure 1), thereby improving the pulverized coal flow in the pulverized coal pipeline through the resistance adjustment device ( Shrinkage cavity) after flow uniformity, it is beneficial to improve the concentration of pulverized coal, the representativeness and accuracy of pulverized coal airflow sampling, and improve the accuracy of wind speed measurement;

The cold primary air or the existing sealing air is used as the sealing air of the device, which is connected to the annular sealing air duct, which effectively solves the problem of clogging of traditional shrinkage cavities and powder accumulation, and improves the reliability of the device; at the same time, it avoids the blockage of the traditional coal mill outlet speed closing device. Issues with slow or lax closures.

As shown in Figure 9, an embodiment of the utility model provides a pulverizing system, the pulverizing system includes: a coal mill, a plurality of pulverized coal pipelines 901 connected to the coal mill, arranged in each coal pulverizer The wind speed measuring device 902 on the pulverized coal pipeline 901 and the coal mill outlet speed closing device 903 arranged on each pulverized coal pipeline 901 .

As shown in Fig. 2 and Fig. 3, the coal mill outlet quick-closing device 903 in Fig. 9 includes: a rectangular sealing box body 9, two first sealing plates 3, a baffle mechanism, a transmission mechanism 6, a driving device 7 and an annular Seal the duct.

As shown in FIG. 4 , the rectangular sealed box body 9 is welded between two sections 10 of powder delivery pipelines 11 through two bottom surfaces. The two first sealing plates 3 , the baffle mechanism and the transmission mechanism 6 are all arranged inside the rectangular sealed box body 9 , and the driving device 7 is arranged outside the rectangular sealed box body 9 , which is not shown in FIG. 4 .

As shown in FIG. 2 and FIG. 3 , the two first sealing plates 3 are respectively arranged on two opposite sides 12 , 13 of the rectangular sealing box 9 .

The baffle plate mechanism is composed of a plurality of baffle plates 1 and a plurality of rotating shafts 2 that drive the baffle plates to rotate. The two ends of the plurality of rotating shafts 2 are respectively fixed in parallel on the other two opposite sides 14, 15 of the rectangular sealed box body 9, and the two The first sealing plate 3 and the rotating shaft 2 are in the same plane. As shown in Fig. 3 and Fig. 5, along the direction of the rotating shaft, one side 16 of the upper bottom surface of each baffle plate 1 and the opposite side 17 of the lower bottom surface respectively have an L-shaped gap (or called a groove) 18, so that when the baffle plate 1 When the plates 1 are closed, the notches between adjacent baffles can cooperate with each other and the notch of one of the outermost baffles can cooperate with said first sealing plate. When the baffles 1 are closed, the relationship between the baffles is shown in Figure 5. After the adjacent baffles are bonded together, and after the two outermost baffles are bonded to the two first sealing plates 3, the L The shaped gap plays a very good sealing role, which can ensure that the blade baffle can effectively block the passage of airflow after the blade baffle is closed, and realize reliable blocking.

The transmission mechanism 6 is connected to the plurality of rotating shafts 2 respectively. The driving device 7 is connected to the transmission mechanism 6 to drive the transmission mechanism to drive a plurality of rotating shafts 2 to rotate respectively, and finally drive the baffle plate 1 to rotate around the rotating shaft. In one embodiment, the baffle plate 1 is a blade baffle plate. The utility model is not based on This is the limit.

As shown in Figure 2, the annular sealed air duct 4 is set on the outer surface of the rectangular sealed box body 9, the outer surface of the annular sealed air duct 9 is provided with a sealed air inlet 8, and the inner surface of the annular sealed air duct is provided with a plurality of sealing Air inlet 19, sealing air inlet 19 introduces sealing air in the rectangular sealed box body 9. The sealing air enters the annular sealing air duct 4 of the quick-closing device at the exit of the coal mill from the sealing air inlet 8 shown in FIG. 2 . The pressure of the sealing wind is about 2 times of the pressure of the air-powder mixture in the powder delivery pipeline, and can enter the inside of the rectangular sealed box body 9 from multiple directions through a plurality of sealing air inlets 19, and the air is formed by the gap between the blade baffle plate and the powder delivery pipeline. The gap enters the powder conveying pipeline, which plays a role in blocking the pulverized coal from entering the quick-closing device at the exit of the pulverizer, preventing the accumulation of pulverized coal from blocking the blade baffle or the transmission mechanism, and affecting the flexibility of the mechanism adjustment.

From the above analysis, it can be seen that when the air-powder mixture flows through the coal mill outlet speed-closing device of the utility model, the coal mill outlet speed-closing device will produce different system resistances at different opening positions, thereby affecting the air-powder mixture. Flow velocity and pulverized coal concentration. The wind-powder mixture is used in conjunction with the downstream wind speed measuring device (also can be a pulverized coal concentration measuring device) 2, and the wind speed monitored by the device 2 ( Measured by the wind speed measuring device) or pulverized coal concentration (measured by the pulverized coal concentration measuring device), thus achieving the purpose of dynamic adjustment.

When the "coal mill outlet speed closing device receives a closing command, the driving device 7 controls the blade baffle to quickly close to the minimum opening to realize the sealing and isolation of the pulverizer pipeline, thereby realizing the coal mill outlet baffle. Quick shutdown function.

Utilizing the quick-closing device at the outlet of the coal mill of the utility model, the air-powder mixture coming out of the coal mill and entering the powder conveying pipeline only needs to pass through a quick-closing device at the outlet of the coal mill with the function of resistance adjustment, so that various The dynamic adjustment of the flow velocity in the powder conveying pipeline and the shut-off isolation function ensure that the wind speed of the air-powder mixture at each corner is consistent, making the flow field of the air-powder mixture in the powder conveying pipeline more uniform, so that the wind speed measuring device or the pulverized coal concentration measuring device is used for powder conveying. The installation on the pipeline provides a better and more compliant location to create conditions, effectively solving the problems of poor fluidity of the air-powder mixture and uneven airflow of the air-powder mixture caused by too short pulverized coal pipelines and insufficient installation space in most power plant pulverization systems , to better meet the field test requirements.

The above-mentioned coal mill outlet quick-closing device is only equipped with two first sealing plates on the two opposite sides (two sides parallel to the rotating shaft) 12 and 13 on which the rotating shaft 2 is not fixed on the rectangular sealing box body 9 3. The sealing baffles are not fixed on the two opposite sides 14 , 15 of the fixed rotating shaft 2 . In order to make the sealing better, in one embodiment, as shown in FIG. 6 , multiple pairs of second sealing plates 20 are arranged on the two opposite sides 14, 15 of the fixed rotating shaft 2, and multiple pairs of second sealing plates 20 20 and a plurality of rotating shafts 2 are in the same plane, and the two baffles of each pair of second sealing plates are separated on both sides of one end of a rotating shaft, so that when the baffles are closed, each pair of second sealing plates is respectively connected to the corresponding baffle. The notches on both sides of the board fit. Next, with reference to FIG. 7 and FIG. 8 , taking one of the rotating shafts 2 on the side 14 as an example, how to achieve sealing through each pair of second sealing plates 20 will be described. As shown in Figure 7, the fixed rotating shaft 2 on the side 14 rotates, and drives the baffle plate 1 to rotate clockwise, so that the closed state shown in Figure 8 can be obtained, the two baffle plates 21, 22 of the second sealing plate 20 The L-shaped notches 18 of the baffle 1 are respectively filled to achieve better sealing.

The above-mentioned driving device 7 may be a pneumatic or electric driving device, such as an electric motor or a pneumatic motor. The transmission mechanism 6 of the quick-closing device at the outlet of the coal mill is driven by a pneumatic or electric drive device, and can be quickly closed within 3 seconds, meeting the requirements of rapid fuel cut-off in accident conditions or normal outage conditions.

In one embodiment, the number of baffle mechanisms is five, and the present invention is not limited thereto. The blade baffle can be made of wear-resistant alloy, and altogether 5 pieces are enclosed in the rectangular sealed box body (metal shell) 9, and are installed in the pulverized coal pipeline, as shown in Figure 3, the blade is in the transmission device 7 Driven to open and close at the same time, it plays the role of closing the baffle or uniform throttling. The multi-blade baffle structure of the exit speed closing device of the coal mill has more flexible blade movements and uniform resistance adjustment, which can evenly adjust the flow rate and ensure the consistency of the flow field after throttling. In addition, the blade baffle of the quick-closing device at the exit of the coal mill can realize the pneumatic control and adjustment operation within the full-open and full-close range, making it possible to dynamically adjust the resistance of the pulverized coal pipeline system during the normal operation of the pulverized coal pulverized system.

After adopting the quick-closing device at the outlet of the coal mill, a group of installation parts (i.e. canceling 1 and 2 in Figure 1) will be canceled for the powder conveying pipeline of the pulverized coal mill pulverization system, and the original function will be realized by using the quick-closing device at the outlet of the coal mill . Its working process is:

Utilizing the quick-closing device at the outlet of the coal mill of the utility model, the air-powder mixture coming out of the coal mill and entering the powder delivery pipeline only needs to pass through a quick-close door at the outlet of the coal mill with the function of resistance adjustment, so that each delivery can be realized at the same time. The dynamic adjustment of the flow velocity in the powder pipeline and the shut-off isolation function ensure that the wind speed of the air-powder mixture at each corner is consistent, making the flow field of the air-powder mixture in the powder pipeline more uniform, so that the wind speed measurement device or the pulverized coal concentration measurement device is in the powder pipeline. The installation on the ground provides a better and more compliant location to create conditions, effectively solving the problems of poor fluidity of the air-powder mixture and uneven air flow caused by the short pulverized coal pipelines and insufficient installation space of most power plant pulverization systems. Better meet the requirements of on-site testing.

In summary, the beneficial effects of the embodiments of the present invention are:

The "two-in-one" combination of the traditional coal mill outlet door and the resistance adjustment device can meet the rapid closing and adjustment of the resistance of the pulverized coal pipeline, reduce the equipment installed on the pulverized pipeline, and reduce the workload of maintenance;

After the pulverizing system adopts the coal mill outlet speed-closing device of the utility model, a group of installation parts will be reduced in the pulverized pipeline, which will provide a better and more compliant position for the installation of the wind speed measuring device on the pulverized pipeline to create conditions, and then It effectively solves the problems of poor fluidity of air powder mixture and uneven air flow of air powder caused by too short pulverized coal pipelines and insufficient installation space in most power plant pulverization systems, and better meets the requirements of field tests.

The new device adopts a pneumatic control method, which has the functions of a speed-closing device at the exit of the coal mill and a resistance adjustment function, and can be operated remotely, making it possible to dynamically adjust the resistance of the powder conveying pipeline in random groups, improving the control flexibility of the resistance adjustment device, and improving the combustion efficiency. Create conditions for dynamic and precise control of pulverized coal velocity and concentration at each corner of the process;

The form of multi-blade baffles is adopted, and each blade is adjusted synchronously, avoiding the non-linear and uneven resistance adjustment of the traditional two-piece shrinkage cavity (shown in Figure 1), thereby improving the pulverized coal flow in the pulverized coal pipeline through the resistance adjustment device ( Shrinkage cavity) after flow uniformity, it is beneficial to improve the concentration of pulverized coal, the representativeness and accuracy of pulverized coal airflow sampling, and improve the accuracy of wind speed measurement;

The cold primary air or the existing sealing air is used as the sealing air of the device, which is connected to the annular sealing air duct, which effectively solves the problem of clogging of traditional shrinkage cavities and powder accumulation, and improves the reliability of the device; at the same time, it avoids the blockage of the traditional coal mill outlet speed closing device. Issues with slow or lax closures.

In the utility model, specific examples have been applied to explain the principle and implementation of the utility model, and the explanations of the above examples are only used to help understand the method of the utility model and its core idea; meanwhile, for those of ordinary skill in the art According to the idea of the present utility model, there will be changes in the specific implementation and scope of application. In summary, the content of this specification should not be construed as a limitation of the present utility model.

Claims (10)

1. A quick-closing device at the outlet of a coal mill, characterized in that, the quick-closing device at the outlet of a coal mill comprises: A rectangular sealed box body, the rectangular sealed box body is welded between two sections of powder conveying pipelines through two bottom surfaces; Two first sealing plates are arranged on two opposite sides of the rectangular sealing box; The baffle mechanism is composed of a plurality of baffles and a plurality of rotating shafts that drive the baffles to rotate. The two ends of the plurality of rotating shafts are respectively fixed in parallel on the other two opposite sides of the rectangular sealed box body, and the first seal The plate and the rotating shaft are in the same plane; along the direction of the rotating shaft, one side of the upper bottom surface of each baffle plate and the opposite side of the lower bottom surface respectively have an L-shaped gap, so that when the baffle plate is closed, the gap between the adjacent baffle plates The gaps between each other cooperate with each other, and the gap of one of the outermost baffles cooperates with the first sealing plate; The transmission mechanism is respectively connected with multiple rotating shafts; a driving device, connected to the transmission mechanism, for driving the transmission mechanism; The annular sealed air duct is set on the outer side of the rectangular sealed box, the outer surface of the annular sealed air duct is provided with a sealed air inlet, and the inner surface of the annular sealed air duct is provided with a plurality of sealed air inlets. The sealing air inlet introduces the sealing air into the rectangular sealing box. 2. The coal mill outlet quick-closing device according to claim 1, characterized in that, the coal mill outlet quick-close door device further comprises: Multiple pairs of second sealing plates are arranged on two opposite sides of the fixed rotating shaft, and are in the same plane as the plurality of rotating shafts, and each pair of second sealing plates is separated on both sides of one end of a rotating shaft, so that When the baffle is closed, each pair of second sealing plates respectively cooperates with the notches on both sides of the baffle. 3. The coal mill outlet quick-closing device according to claim 1, characterized in that the drive device is a pneumatic or electric drive device. 4. The coal mill outlet quick-closing device according to claim 1, characterized in that the number of said baffle mechanisms is five. 5. The coal mill outlet quick-closing device according to claim 1, characterized in that the rectangular sealed box is a metal box. 6. A coal pulverization system, characterized in that, the pulverization system comprises: a coal pulverizer, a plurality of pulverized coal pipelines connected to the pulverizer, arranged on each of the pulverized coal pipelines The wind speed measuring device and the coal mill outlet speed closing door device according to claim 1 are arranged on each pulverized coal pipeline. 7. The pulverized coal pulverization system according to claim 6, characterized in that, the quick-closing device at the outlet of the coal mill further comprises: Multiple pairs of second sealing plates are arranged on two opposite sides of the fixed rotating shaft, and are in the same plane as the plurality of rotating shafts, and each pair of second sealing plates is separated on both sides of one end of a rotating shaft, so that When the baffle is closed, each pair of second sealing plates respectively cooperates with the notches on both sides of the baffle. 8. The coal pulverization system according to claim 6, characterized in that the drive device is a pneumatic or electric drive device. 9. The coal pulverization system according to claim 6, wherein the number of said baffle mechanisms is five. 10. The coal pulverization system according to claim 6, wherein the rectangular sealed box is a metal box.