Pebble coal full-sealing system of unit boiler coal mill
By designing a fully sealed system for the coal mill of the boiler unit, the sealed discharge of coal stones was achieved, solving the dust pollution problem in the process of coal stone discharge in thermal power plants and improving environmental sanitation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-17
- Publication Date
- 2026-04-03
AI Technical Summary
The dust generated during the discharge of coal from the coal mills in the boilers of existing thermal power plants is severe, resulting in poor environmental sanitation.
Design a fully sealed system for stone coal in a boiler coal mill, including a coal mill, slag discharge pipe, support frame, movable slag box, lifting device and control device. The sealed discharge of stone coal is achieved through sealed connection, and the sealing and safety are ensured by using a negative pressure machine and spray system.
It improved the sealing of the coal mill's stone and coal discharge process, improved the environmental hygiene of thermal power plants, and reduced dust pollution.
Smart Images
Figure CN224072188U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of power plant coal mill technology, and in particular to a fully sealed system for stone coal in a unit boiler coal mill. Background Technology
[0002] The coal mill in the boiler unit is an important piece of equipment in a thermal power plant, while coke is a waste product generated during the coal powder preparation process in a thermal power plant (i.e., unground pyrite and entrained gangue and coal particles), which is mainly discharged from the coal mill.
[0003] Currently, most coal mills in thermal power plants utilize a buffer-type on-site ash discharge system. This involves sequentially installing an upper ash discharge valve, a buffer ash storage tank, a lower ash discharge valve, and an open-top ash discharge car at the ash outlet of the coal mill. The ash discharge method is open and on-site, requiring manual removal. Because the coking coal generates significant dust during the final ash discharge and transfer process, working conditions inside the plant are extremely poor, severely impacting the environmental hygiene of the thermal power plant. Therefore, this application proposes a fully sealed coking coal discharge system for coal mills in thermal power plant boilers. Utility Model Content
[0004] This application provides a fully sealed system for the coal mill of a boiler unit to solve the technical problems described in the background section.
[0005] In some embodiments, this application adopts the following technical solutions for implementation:
[0006] This application provides a fully sealed system for the stone coal in a boiler coal mill, comprising:
[0007] A coal mill, wherein a slag discharge pipe is inclined downwards and connected to the slag discharge port of the coal mill, and a first slag discharge valve is provided on the slag discharge pipe;
[0008] A support frame is provided with a connecting plate at its top. The end of the slag discharge pipe away from the coal mill passes through the connecting plate and is sealed to the connecting plate. A vertical insert plate is provided around the slag discharge pipe on the lower surface of the connecting plate.
[0009] A movable slag box, which can be moved to the bottom of the support frame and has a slag inlet on its top, and the top surface of the slag inlet is provided with a sealing slot that matches the vertical insert plate;
[0010] The lifting device, comprising at least two devices evenly spaced around the slag discharge pipe on the lower surface of the connecting plate, is used to lift the movable slag box until the vertical insert plate is inserted into the sealing slot.
[0011] Optionally, the fully sealed coal mill stone and coal system of the unit boiler in this application also includes a control device installed in the central control room of the power plant;
[0012] Both the first slag discharge valve and the lifting device are electrically connected to the control device.
[0013] Optionally, a pressure relief pipe is provided through the connecting plate, and the end of the pressure relief pipe away from the connecting plate is used to connect to a negative pressure machine, which is electrically connected to the control device.
[0014] Optionally, a viewing window is provided on the side wall of the mobile slag box, and the bottom of the viewing window is located at 2 / 3 to 3 / 4 of the height of the mobile slag box.
[0015] Optionally, a material level switch is provided on the connecting plate. The bottom end of the material level switch can extend into the movable slag box to detect the material level in the movable slag box. The material level switch is electrically connected to the control device.
[0016] Optionally, a second slag discharge valve is provided on the pipe body between the first slag discharge valve and the connecting plate in the slag discharge pipeline, and the second slag discharge valve is electrically connected to the control device.
[0017] Optionally, the connecting plate is equipped with a temperature alarm that can detect the temperature inside the mobile slag box, and the temperature alarm is electrically connected to the control device.
[0018] Optionally, a spray pipe runs through the connecting plate, one end of the spray pipe can extend into the movable slag box and the other end is used to connect to a water source, and a water pump electrically connected to the control device is provided on the spray pipe.
[0019] Optionally, the mobile slag box is made of Q345 steel and has a wall thickness of ≥10mm.
[0020] Optionally, a sealing strip is provided inside the sealing slot, and the sealing strip is made of high-temperature resistant sealing rubber.
[0021] The fully sealed coal discharge system for a boiler pulverizer provided in this application involves setting up a support frame and a connecting plate at the top of the support frame. The end of the slag discharge pipe connected to the slag discharge port of the pulverizer passes through the connecting plate, away from the pulverizer. Vertical insert plates are installed around the slag discharge pipe on the lower surface of the connecting plate. A movable slag box is moved to the bottom of the support frame and lifted by a lifting device on the lower surface of the connecting plate until the vertical insert plates are inserted into the sealing slots on the top surface of the slag inlet of the movable slag box. This achieves a sealed connection between the movable slag box and the slag discharge pipe, ensuring a tight seal between the pulverizer, the slag discharge pipe, and the movable slag box. This improves the sealing performance of the coal discharge process. Compared to the existing open, on-site slag discharge method used in boiler pulverizers in thermal power plants, this application improves the sealing performance of the boiler pulverizer's slag discharge process and enhances the environmental hygiene of thermal power plants. Attached Figure Description
[0022] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0023] Figure 1 This is a schematic diagram of the structure of a fully sealed coal mill system for a boiler unit, provided in one embodiment of this application.
[0024] Figure 2 A schematic diagram of a connection plate with a vertical slot provided in an embodiment of this application;
[0025] Figure 3 A schematic diagram of a structure in which a vertical slot is provided on the top surface of the slag inlet of a mobile slag box according to an embodiment of this application;
[0026] Figure 4 This is a schematic diagram showing the electrical connections between various components and the control device provided in an embodiment of this application.
[0027] In the diagram: 100, coal mill; 101, slag discharge pipe; 1011, first slag discharge valve; 1012, second slag discharge valve; 200, support frame; 201, connecting plate; 2011, vertical insert plate; 2012, material level switch; 2013, temperature alarm; 300, movable slag box; 301, slag inlet; 3011, sealing slot; 302, viewing window; 400, lifting device; 500, power plant central control room; 501, control device; 600, pressure relief pipe; 700, spray pipe; 701, water pump. Detailed Implementation
[0028] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application are described clearly and completely below. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are also within the scope of protection of this application.
[0029] refer to Figures 1 to 4 This application provides a fully sealed system for stone coal in a boiler coal mill, comprising:
[0030] A coal mill 100 has a downward-sloping slag discharge port connected to a slag discharge pipe 101, on which a first slag discharge valve 1011 is installed. In thermal power plants, the coal mill in the boiler unit is a key piece of equipment for grinding raw coal into pulverized coal, its function being to provide qualified pulverized coal to the boiler to improve combustion efficiency. Depending on different design specifications and actual application requirements, the type, number, and configuration of the coal mill vary, and can be set according to actual needs; however, this application does not impose specific limitations on them. Furthermore, the specifications and model of the first slag discharge valve 1011 can also be set according to actual needs, and this application does not impose specific limitations on them either.
[0031] The support frame 200 has a connecting plate 201 on its top. The end of the slag discharge pipe 101 away from the coal mill 100 passes through the connecting plate 201 and is sealed to the connecting plate 201. The lower surface of the connecting plate 201 is provided with a vertical insert plate 2011 around the slag discharge pipe 101. In order to ensure the stability and continuity of the slag discharge process of the coal mill of the unit boiler, the bottom of the support frame 200 can be fixed to the ground of the power plant building by means of anchor bolts, etc. The specific setting can be set according to the actual situation, and this application does not make a specific limitation.
[0032] The mobile slag box 300 can be moved to the bottom of the support frame 200 and has a slag inlet 301 on its top. The top surface of the slag inlet 301 is provided with a sealing slot 3011 that matches the vertical insert plate 2011. The bottom of the mobile slag box 300 is provided with lockable casters that can move relative to the ground of the thermal power plant building. The movement of the mobile slag box 300 can be achieved by pulling or pushing it with external force (e.g., by workers).
[0033] At least two lifting devices 400 are evenly spaced around the slag discharge pipe 101 on the lower surface of the connecting plate 201. These devices are used to lift the movable slag box 200 until the vertical insert plate 2011 is inserted into the sealing slot 3011. The lifting device 400 can be a hydraulic cylinder, etc., and can be selected according to actual needs; this application does not specifically limit its use. Specifically, the movable slag box 300 is equipped with a lifting ring, and the bottom end (i.e., the lifting end) of the lifting device 400 is equipped with a hook that matches the lifting ring. During the lifting process, the lifting device 400 lifts the movable slag box 300 through the cooperation of the hook on the lifting device 400 and the lifting ring on the movable slag box 300. The aforementioned lifting ring and hook are only one possible implementation of lifting the movable slag box 300 using the lifting device 400, and this application is not limited to this method; specific implementations can be made according to actual conditions. In addition, there are at least two lifting devices 400 arranged at equal intervals around the slag discharge pipe 101 on the lower surface of the connecting plate 201, which ensures the stability and safety of the lifting device in the process of lifting the moving slag box 300.
[0034] The fully sealed coal mill stone and coal system for the boiler unit provided in this application involves setting up a support frame 200 and a connecting plate 201 on the top of the support frame 200. The end of the slag discharge pipe 101 connected to the slag discharge port of the coal mill 100, away from the coal mill 100, passes through the connecting plate 201. A vertical insert plate 2011 is set around the slag discharge pipe 101 on the lower surface of the connecting plate 201. The mobile slag box 300 is moved to below the support frame 200, and the mobile slag box 300 is lifted by a lifting device 400 set on the lower surface of the connecting plate 201 until the vertical insert plate 2011 is inserted into the inlet of the mobile slag box 300. The sealing slot 3011 on the top surface of the slag outlet 301 achieves a sealed connection between the movable slag box 300 and the slag discharge pipe 101 (at this time, the end of the slag discharge pipe 101 away from the coal mill 100 extends into the movable slag box 300), ensuring the sealing effect between the coal mill 100, the slag discharge pipe 101 and the movable slag box 300, thereby improving the sealing performance of the coal mill's stone coal discharge process. Compared with the existing open on-site slag discharge method of the coal mill in the unit boiler of thermal power plants, this application improves the sealing performance of the coal mill's slag discharge process and improves the environmental hygiene of thermal power plants.
[0035] In some embodiments, reference Figure 4 The fully sealed coal mill stone coal system of the unit boiler in this application also includes a control device 501 installed in the central control room 500 of the power plant; wherein, the control device 501 can be a control cabinet integrating electronic control components, electronic detection components, etc., and can be set and selected according to actual needs, but this application will not further elaborate or limit it here.
[0036] In addition, both the first slag discharge valve 1011 and the lifting device 400 are electrically connected to the control device 501. This allows the first gate valve 1011 to be opened or closed via the control device 501, replacing manual operation and thus improving the operating efficiency of the first slag discharge valve 1011. The first gate valve can also be manually opened or closed by personnel.
[0037] In some embodiments, reference Figure 1 In this application, a pressure relief pipe 600 is provided through the connecting plate 201. The end of the pressure relief pipe 600 away from the connecting plate 201 is used to connect to a negative pressure machine, which is electrically connected to the control device 501. The specifications and model of the negative pressure machine can be set according to actual needs, and this application does not specifically limit them. Furthermore, to prevent coal dust and other materials from entering the pressure relief pipe 600 and the negative pressure machine during the slag discharge process, thus avoiding blockage and wear that could affect the suction and release processes of the negative pressure machine, this application provides a check valve (not shown in the figure) on the pipe body of the pressure relief pipe 600 near the connecting plate 201.
[0038] In the actual slag discharge process, when the lifting device 400 lifts the mobile slag box 300 to the point where the vertical insert plate 2011 is sealed and inserted into the sealing slot 3011, in order to further ensure the sealed connection between the mobile slag box 300 and the connecting plate 201, the air extraction button on the negative pressure machine is turned on (during this process, the check valve is in the open state). The negative pressure machine draws the mobile slag box 300 to a negative pressure state, making the connection between the mobile slag box 300 and the connecting plate 201 tighter. When the slag in the mobile slag box 300 is discharged to the capacity that the mobile slag box 300 can hold, the air release button on the negative pressure machine is turned on to start depressurization (during this process, the check valve is in the open state) until the only force between the mobile slag box 300 and the connecting plate 201 is the lifting force of the lifting device 400. Then the check valve is closed, and the mobile slag box 300 containing the slag is placed on the ground of the power plant building by the lifting device 400 to achieve sealed discharge of the slag. The above process prevents coal dust and other materials from entering the pressure relief pipe 600 and the negative pressure machine, ensuring the smooth operation of the negative pressure machine's air extraction and venting processes.
[0039] In some embodiments, reference Figure 1 In this application, a viewing window 302 is provided on the side wall of the mobile slag box 300, and the bottom end of the viewing window 302 is located at 2 / 3 to 3 / 4 of the height of the mobile slag box 300.
[0040] In the above embodiments, the setting and specific location of the visual observation window 302 ensure that during the slag discharge process, it is convenient for staff to observe the slag level in the mobile slag box 300 in a timely manner. When the slag level is close to the maximum level that the mobile slag box 300 can accommodate, the staff at the mobile slag box 300 can call the staff in the power plant's central control room 500 through walkie-talkies or other means. The staff in the power plant's central control room 500 can then operate the control device 501 to close the first slag discharge valve 1011 in a timely manner, thus ensuring the efficiency of the slag discharge process.
[0041] In some embodiments, reference Figure 1 and Figure 4 In this application, a level switch 2012 is installed on the connecting plate 201. The bottom end of the level switch 2012 can extend into the movable slag box 300 to detect the material level inside the movable slag box 300. The level switch 2012 is electrically connected to the control device 501. The level switch 2012 is mainly used for measuring high, low, or intermediate material levels in containers and storage tanks. It is installed at fixed points on the top, side, or bottom of the silo via threads or flanges, and includes rotary paddle level switches, tuning fork level switches, capacitive level switches, and radio frequency admittance level switches. The level switch 2012 in this application can be installed on the connecting plate 201 via a flange. Its specifications and model can be set according to actual needs, and this application does not specifically limit it.
[0042] In the above embodiment, the visual observation window 302 facilitates the staff to observe the material level in the mobile slag box 300 with their naked eyes. The material level switch 2012 can detect the material level in the mobile slag box 300 in real time as the slag discharge process proceeds and transmit the detected material level to the control device 501. When the material level in the mobile slag box 300 approaches the maximum material level of the mobile slag box 300, the control device 501 will receive this signal and close the first slag discharge valve 1011. In other words, the material level switch 2012 improves the accuracy of material level detection in the mobile slag box 300.
[0043] In some embodiments, reference Figure 1In this application, a second slag discharge valve 1012 is installed on the pipe body between the first slag discharge valve 1011 and the connecting plate 201 in the slag discharge pipe 101. The second slag discharge valve 1012 is electrically connected to the control device 501. During the slag discharge process from the coal mill 100, slag and slag powder may cause wear to the first slag discharge valve 1011. As the slag discharge process continues, the opening and closing of the first slag discharge valve 1011 may be damaged. To ensure that the slag discharge process is not affected and can proceed smoothly, the second slag discharge valve 1012 is installed to control the slag discharge process, thereby ensuring the smooth operation of the slag discharge process of the coal mill 100. Furthermore, when either the first slag discharge valve 1011 or the second slag discharge valve 1012 is under maintenance, the other valve can still operate normally to control the slag discharge process.
[0044] In some embodiments, reference Figure 4 In this application, the connecting plate 201 is equipped with a temperature alarm 2013 capable of detecting the temperature inside the mobile slag box 300. The temperature alarm 2013 is electrically connected to the control device 501. The temperature alarm 2013 is an instrument that uses a temperature sensor to detect the external temperature in real time. When the temperature exceeds or falls below a threshold set by the user, an alarm is issued.
[0045] In the above embodiments, the temperature inside the mobile slag box 300 is detected in real time by the temperature alarm 2013 and the detected signal is transmitted to the control device 501. When the temperature inside the mobile slag box 300 is high or even exceeds the maximum temperature that the mobile slag box 300 can accept, in order to avoid the risk of explosion when it comes into contact with an open flame, the control device 501 closes the first slag discharge valve 1011 and performs a cooling operation. The specific cooling operation can be selected according to the actual situation, and this application will not elaborate on it here.
[0046] In some embodiments, reference Figure 1 In this application, a spray pipe 700 is passed through the connecting plate 201. One end of the spray pipe 700 can extend into the movable slag box 300, and the other end is used to connect to a water source. A water pump 701 electrically connected to the control device 501 is installed on the spray pipe 700. The specifications and model of the water pump 701 can be set according to actual needs, and this application does not impose specific limitations on it.
[0047] In the above embodiment, when the temperature alarm 2013 detects that the temperature inside the mobile slag box 300 is high or even exceeds the maximum temperature that the mobile slag box 300 can accept, the control device 501 receives the signal and turns on the water pump 701 to transport water from the water source to the mobile slag box 300 through the spray pipe 700, thereby achieving the purpose of cooling the slag material inside the mobile slag box 300 and avoiding the danger of explosion that may occur when the mobile slag box 300 encounters an open flame.
[0048] In some embodiments, the mobile slag box 300 in this application is made of Q345 steel, and its wall thickness is ≥10mm. Q345 is a low-alloy high-strength structural steel with advantages such as light weight, high strength, and corrosion resistance, making the mobile slag box made of Q345 easy to move and extending its service life.
[0049] In addition, since the mobile slag box 300 contains gravel coal, which is specifically unground pyrite and entrained gangue and coal particles, the gravel coal will cause wear to the mobile slag box 300 during the loading process. In order to ensure the service life of the mobile slag box 300, the wall thickness of the mobile slag box 300 needs to be further limited. A wall thickness of ≥10mm can extend the service life of the mobile slag box 300 and reduce the frequency of maintenance and replacement.
[0050] In some embodiments, a sealing strip is provided inside the sealing slot 3011 of this application, and the sealing strip is made of high-temperature resistant sealing rubber.
[0051] In the above embodiments, the sealing strip improves the tightness of the connection between the vertical insert plate 2011 and the sealing slot 3011, thereby further enhancing the sealing performance between the coal mill 100, the slag discharge pipe 101, and the mobile slag box 300 during the slag discharge process. This prevents dust and other contaminants from overflowing from the connection point between the mobile slag box 300 and the connecting plate 201, thus improving the environmental hygiene of the thermal power plant. Since the temperature of the slag discharged from the coal mill 100 is approximately between 100°C and 150°C, and high-temperature resistant sealing rubber is a material used to provide sealing performance in high-temperature environments, the sealing strip produced using high-temperature resistant sealing rubber in this application ensures the sealing performance of the connection between the vertical insert plate 2011 and the sealing slot 3011, while also extending the service life of the sealing strip. The high-temperature resistant sealing rubber can be silicone rubber, fluororubber, nitrile rubber, hydrogenated nitrile rubber, polyurethane rubber, etc., and can be selected according to actual conditions; however, this application does not specifically limit its application.
[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.
Claims
1. A fully sealed system for stone coal in a boiler coal mill, characterized in that, include: A coal mill (100) has a slag discharge pipe (101) that is inclined downward at the slag discharge port of the coal mill (100), and a first slag discharge valve (1011) is provided on the slag discharge pipe (101). A support frame (200) is provided with a connecting plate (201) at its top. The end of the slag discharge pipe (101) away from the coal mill (100) passes through the connecting plate (201) and is sealed to the connecting plate (201). A vertical insert plate (2011) is provided around the slag discharge pipe (101) on the lower surface of the connecting plate (201). A movable slag box (300) is movable to the bottom of the support frame (200) and has a slag inlet (301) on its top. The top surface of the slag inlet (301) is provided with a sealing slot (3011) that matches the vertical insert plate (2011). Lifting devices (400), at least two of which are equally spaced around the slag discharge pipe (101) on the lower surface of the connecting plate (201), are used to lift the movable slag box (300) until the vertical insert plate (2011) is inserted into the sealing slot (3011).
2. The fully sealed coal mill pebble system for a boiler unit as described in claim 1, characterized in that, It also includes a control device (501) installed in the central control room (500) of the power plant. The first slag discharge valve (1011) and the lifting device (400) are both electrically connected to the control device (501).
3. The fully sealed coal mill pebble system for a boiler unit as described in claim 2, characterized in that, A pressure relief pipe (600) is provided through the connecting plate (201). The end of the pressure relief pipe (600) away from the connecting plate (201) is used to connect to the negative pressure machine (601). The negative pressure machine (601) is electrically connected to the control device (501).
4. The fully sealed coal mill stone and coal system for a boiler unit according to claim 2, characterized in that, A viewing window (302) is provided on the side wall of the mobile slag box (300), and the bottom of the viewing window is located at 2 / 3 to 3 / 4 of the height of the mobile slag box.
5. The fully sealed coal mill pebble system for a boiler unit as described in claim 4, characterized in that, A material level switch (2012) is provided on the connecting plate (201). The bottom end of the material level switch (2012) can extend into the movable slag box (300) to detect the material level in the movable slag box (300). The material level switch (2012) is electrically connected to the control device (501).
6. The fully sealed coal mill pebble system for a boiler unit according to claim 2, characterized in that, The slag discharge pipe (101) has a second slag discharge valve (1012) installed on the pipe body between the first slag discharge valve (1011) and the connecting plate (201), and the second slag discharge valve (1012) is electrically connected to the control device (501).
7. The fully sealed coal mill pebble system for a boiler unit according to claim 2, characterized in that, The connecting plate (201) is equipped with a temperature alarm (2013) that can detect the temperature inside the mobile slag box (300), and the temperature alarm (2013) is electrically connected to the control device (501).
8. The fully sealed coal mill pebble system for a boiler unit according to claim 7, characterized in that, A spray pipe (700) runs through the connecting plate (201). One end of the spray pipe (700) can extend into the movable slag box (300), and the other end is used to connect to a water source. A water pump (701) electrically connected to the control device (501) is provided on the spray pipe (700).
9. The fully sealed coal mill stone and coal system for a boiler unit according to any one of claims 1 to 8, characterized in that, The mobile slag box (300) is made of Q345 steel and has a wall thickness of ≥10mm.
10. The fully sealed coal mill stone and coal system for a boiler unit according to any one of claims 1 to 8, characterized in that, A sealing strip is provided inside the sealing slot (3011), and the sealing strip is made of high-temperature resistant sealing rubber.