Adjustable shrinkage cavity and intelligent control system of coal mill

Abstract

The invention relates to the technical field of coal mills, in particular to a coal mill adjustable shrinkage cavity and intelligent control system which comprises an adjusting assembly, an adjusting piece, a component and a gas piece, the component is arranged on the adjusting piece, and the gas piece is arranged on the adjusting piece; the control assembly comprises an output piece, a supporting piece and a connecting rod piece, the output piece is arranged on the adjusting piece, the supporting piece is arranged on the output piece, the connecting rod piece is arranged on the supporting piece, and the amount of pulverized coal in the pulverized coal pipe is controlled by adjusting the opening degree of the shrinkage cavity under any working condition through DCS logic; adjusting the air powder speed at the outlet of each adjustable shrinkage cavity under different working conditions according to a combustion experiment; a manual mode and a protection switch function are used, operation is automatically quitted under special working conditions or accident conditions, the problem that deviation exists in the air speed of pulverized coal at outlets of a plurality of different combustors corresponding to the same coal mill under different working conditions is solved through application achievements, and the consistency of the pulverized coal speed at the outlets of the combustors under different loads of a unit is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of coal mills, and in particular to an adjustable shrinkage hole and an intelligent control system of a coal mill. Background Art

[0002] In the prior art, the primary air-cooled leveling of the power plant boiler pulverizing system is controlled by a single-core or double-core adjustable shrinkage device with a screw and hand wheel on site to control the air-powder velocity. As the unit load changes, the speed of the air-powder in the pulverized coal pipe can only rely on the primary air pressure and the opening of the cold and hot air valves of the coal mill. When the inlet air pressure of the pulverizing system is constant, the primary air speed of each pulverized coal pipe cannot be leveled. The reason is that the adjustable shrinkage hole is rarely operated after the cold state test. When it is adjusted again, powder often accumulates inside, causing the mechanism to become stuck and inflexible, stuck and unable to adjust, which hinders normal operation and is useless. In addition, the DCS screen cannot monitor the air-powder velocity value of each primary powder pipe, and cannot eliminate the deviation of the air-powder velocity in each pulverized coal pipe at the outlet of the coal mill, cannot ensure the uniformity of the pulverized coal in the pulverized coal pipe at the outlet of the coal mill, and cannot achieve the optimal velocity corresponding to the burner combustion experiment.

[0003] After the boiler is put into operation, relevant units will conduct relevant experiments on the pulverizing system to confirm the air-powder deviation between the outlet coal air ducts of the same coal mill under different working conditions, and ensure that the outlet air-powder wind speeds of the same coal mill corresponding to several different burners are the same. However, after the unit has been running for 168 hours, the speed of the air-powder in the coal pulverizer pipe can only be controlled by the primary wind pressure and the opening of the cold and hot air valves of the coal mill or by manually adjusting the adjustable shrinkage hole with the change of the unit load during actual operation, and the consistency of the burner outlet coal pulverizer speed under different unit loads cannot be guaranteed, and the combustion conditions cannot be guaranteed to be optimal. In order to solve this problem, a coal pulverizer outlet coal valve adjustable shrinkage hole and intelligent adjustment system are designed. Summary of the invention

[0004] In view of the above problems existing in the existing coal mill, the present invention is proposed.

[0005] Therefore, the object of the present invention is to provide an adjustable shrinkage hole and intelligent control system for a coal mill.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: an adjustable shrinkage hole of a coal mill, comprising:

[0007] An adjusting component, comprising an adjustable shrinkage hole, a component and a gas component, wherein the component is arranged on the adjustable shrinkage hole, and the gas component is arranged on the adjustable shrinkage hole; and

[0008] The control component comprises an output member, a support member and a connecting rod member, wherein the output member is arranged on the adjustable shrinkage hole, the support member is arranged on the output member, and the connecting rod member is arranged on the support member.

[0009] As a preferred solution of an adjustable shrinkage hole of a coal mill of the present invention, the adjustable shrinkage hole includes a baffle arranged on the inner side of the adjustable shrinkage hole, a fixed bracket arranged on the outer shell, a crank-connecting rod mechanism arranged at the center position of the fixed bracket, and a transmission shaft arranged on the inner side of the baffle.

[0010] As a preferred solution of the adjustable shrinkage hole of a coal mill of the present invention, the components include the left and right ends of the transmission shaft embedded in the inner wall of the adjustable shrinkage hole, the right end of the transmission shaft passes through the outer wall of the adjustable shrinkage hole, the inner wall and the outer wall are both provided with hollow layers, and gaps are provided between the baffles.

[0011] As a preferred solution of the adjustable shrinkage hole of a coal mill of the present invention, the gas component comprises a pipeline arranged on the adjustable shrinkage hole, and an isolation door is arranged on the pipeline.

[0012] As a preferred solution of the adjustable shrinkage hole of a coal mill of the present invention, the output member includes an electric actuator arranged at the lower end of the crank-connecting rod mechanism, a first connecting rod arranged on the electric actuator, a third connecting rod arranged on the first connecting rod, and a second connecting rod arranged on the third connecting rod.

[0013] As a preferred solution of the adjustable shrinkage hole of a coal mill of the present invention, the support member includes a pin arranged on the third connecting rod, a bracket arranged on the third connecting rod, and a rotating shaft arranged on the bracket.

[0014] As a preferred solution of the adjustable shrinkage hole of a coal mill of the present invention, the connecting rod member includes a fourth connecting rod arranged on the third connecting rod and a fifth connecting rod arranged on the fourth connecting rod.

[0015] An intelligent control system for adjustable shrinkage holes of a coal mill, including the above-mentioned adjustable shrinkage holes of a coal mill, comprises the following steps:

[0016] Through DCS logic, the amount of air and powder in the pulverized coal pipe can be controlled by adjusting the shrinkage hole opening under any working conditions;

[0017] According to the combustion experiment, the air-powder velocity at each adjustable shrinkage hole outlet under different working conditions is adjusted;

[0018] Use manual mode and protection shutdown function to automatically exit operation in case of special working conditions or accidents.

[0019] As a preferred solution of the intelligent control system for adjustable shrinkage holes of a coal mill of the present invention, the wind speed automatic adjustment logic in the DCS includes the setting of the reference pulverized coal pipe wind speed and the setting of the wind speed difference K of the other four pulverized coal pipes. Different coal quantities correspond to different primary air volumes. The air-coal ratio is generally controlled to be between 2-2.5. When the actual air-powder speed is smaller than the set value of the air-powder speed, the PID automatically outputs a command to gradually open the adjustable shrinkage hole regulating valve; when the actual air-powder speed is larger than the set value of the air-powder speed, the PID automatically outputs a command to gradually close the adjustable shrinkage hole regulating valve.

[0020] As a preferred solution of the intelligent control system for adjustable shrinkage holes of a coal mill of the present invention, in manual mode, the operating personnel directly output the adjustment valve command manually through each adjustment system M / A station to control the adjustment valve opening; at the same time, the set value tracks the actual value of the wind and powder wind speed in real time through the BIAS bias module (BAIS tracking value = the difference between the actual wind speed value and the primary air volume F(X) value), and the protection shutdown function is used to automatically exit the operation when encountering special working conditions or accidents.

[0021] The beneficial effects of the invention are as follows: the applicable results solve the problem of deviation in the air-powder velocity at the outlets of several different burners of the same coal mill under different working conditions, thereby ensuring the consistency of the coal-powder velocity at the burner outlet under different loads of the unit.

[0022] Accurately control the air-powder speed: Through DCS logic, the amount of air-powder in the pulverized coal pipe is controlled by adjusting the shrinkage hole opening under any working condition, ensuring that the maximum air speed deviation value of each primary air-powder pipe corresponds to the deviation value during the experiment under any working condition, and displaying the real-time value.

[0023] Automatic adjustment function: After the boiler is put into operation, a combustion condition experiment is carried out, and the air-powder velocity at 30° at the adjustable shrinkage hole outlet is adjusted according to different working conditions to eliminate the uneven air-powder velocity caused by resistance differences, thereby optimizing combustion efficiency.

[0024] Manual and automatic mode switching: The system is designed with manual mode and protection shutdown function to ensure safe exit from operation under special working conditions or accidents.

[0025] Reduce manual intervention: The intelligent adjustment system reduces dependence on manual operation and improves the accuracy and efficiency of operation.

[0026] Prevent powder accumulation: The inner and outer walls of the adjustable shrinkage hole are designed as a hollow layer, and compressed air is passed inside to ensure that there is no powder accumulation around the transmission shaft and the baffle can move flexibly.

[0027] Real-time monitoring and feedback: An online wind and powder inspection device is set up to monitor the wind and powder speed in real time, and track the real-time deviation between the actual wind and powder speed and the set value through the BIAS bias module to achieve precise control. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 The present invention is a schematic diagram of the structure of an adjustment component of an adjustable shrinkage hole of a coal mill.

[0030] Figure 2 The present invention is a schematic diagram of the structure of a control component of an adjustable shrinkage hole of a coal mill.

[0031] Figure 3 This is a diagram of a pulverizing system and a burner system of an intelligent control system for adjustable shrinkage holes of a coal mill according to the present invention.

[0032] Figure 4 The DCS logic system diagram of the intelligent control system for adjustable shrinkage holes of a coal mill according to the present invention.

[0033] Figure 5 The present invention is a logic diagram of the pulverized coal pipe adjustable shrinkage hole adjustment system 1, 2, 3 of the coal mill adjustable shrinkage hole intelligent control system.

[0034] Figure 6 The invention provides a coal mill adjustable shrinkage hole intelligent control system, and a pulverizing system is equipped with an intelligent adjustable shrinkage hole system to automatically adjust parameters in real time. DETAILED DESCRIPTION

[0035] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0036] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0037] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor is it a separate or selective embodiment that is mutually exclusive with other embodiments.

[0038] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0039] Example 1

[0040] Reference Figure 1 - Figure 2 , which is the first embodiment of the present invention, provides an adjustable shrinkage hole 101 for a coal mill, and the device comprises an adjusting component 100, comprising an adjustable shrinkage hole 101, a component 102 and a gas component 103, wherein the component 102 is arranged on the adjustable shrinkage hole 101, and the gas component 103 is arranged on the adjustable shrinkage hole 101; and a control component 200, comprising an output component 201, a support component 202 and a connecting rod component 203, wherein the output component 201 is arranged on the adjustable shrinkage hole 101, the support component 202 is arranged on the output component 201, and the connecting rod component 203 is arranged on the support component 202. Through the mutual cooperation of the adjusting component 100 and the control component 200, the design of the shrinkage hole of the electrically adjustable baffle 101a on the adjustable shrinkage hole 101 of the coal mill is realized.

[0041] Specifically, the adjustable shrinkage hole 101 includes a baffle 101a arranged on the inner side of the adjustable shrinkage hole 101, a plurality of baffles 101a are arranged on the inner side of the adjustable shrinkage hole 101, and are rotatably connected, and the plurality of baffles 101a are arranged in a linear array, a fixed bracket 101b is arranged on the outer side of the adjustable shrinkage hole 101, and the fixed bracket 101b is fixedly connected to both sides of the adjustable shrinkage hole 101, a crank connecting rod mechanism is arranged at the center position of the fixed bracket 101b, and a crank connecting rod mechanism 101c is fixedly connected to the center position of the fixed bracket 101b, a transmission shaft 101d is arranged on the inner side of the baffle 101a, and the transmission shaft 101d is embedded in the inner side of the baffle 101a, and the transmission shaft 101d and the baffle 101a are integrated, and the left and right ends are embedded in the inner wall 102a of the adjustable shrinkage hole 101, and the two are movably connected;

[0042] Among them, the component 102 includes a transmission shaft 101d with left and right ends embedded in the inner wall 102a of the adjustable shrinkage hole 101, and the left and right ends of the transmission shaft 101d are embedded in the inner wall 102a of the adjustable shrinkage hole 101. The right end of the transmission shaft 101d passes through the outer wall 102b of the adjustable shrinkage hole 101. In order to reduce friction, a rolling bearing can be set on the inner wall 102a of the adjustable shrinkage hole 101. Both the inner wall 102a and the outer wall 102b are provided with a hollow layer 102c. A gap 102d is provided between the baffles 101a, and compressed air is passed inside to ensure that there is no powder accumulation around the transmission shaft 101d, and the baffle 101a can move flexibly. The baffle 101a is driven to rotate by the transmission shaft 101d to change the size of the gap 102d between the baffles 101a, thereby adjusting the ventilation volume of the adjustable shrinkage hole 101 to change the primary wind speed. When the baffle 101a is in a horizontal position, the baffle 101a is fully closed. In order to ensure that the pulverized coal pipe is continuously blown, a certain gap 102d must be left. When designing, the baffle 101a is fully closed, and the total flow area of ​​the gap 102d accounts for 1 / 3 of the flow area of ​​the entire adjustable shrinkage hole 101;

[0043] Among them, the gas component 103 includes a pipeline 103a arranged on the adjustable shrinkage hole 101, the pipeline 103a is fixedly connected to one side of the adjustable shrinkage hole 101 of the entire coal mill, and an isolation door 103b is arranged on the pipeline 103a. The compressed air inside the adjustable shrinkage hole 101 is connected to the miscellaneous compressed air pipeline 103a through the pipeline 103a. A manual isolation door 103b is fixedly connected to the compressed air pipeline 103a, which is used to isolate compressed air during the maintenance of the coal powder pipe. The compressed air divides the adjustable shrinkage hole 101 into two upper and lower paths, ensuring that the pressure of the hollow layer 102c of the entire adjustable shrinkage hole 101 is the same, and ensuring that there is no powder accumulation and jamming around the transmission shaft 101d.

[0044] Further, the output member 201 includes an electric actuator 201a fixedly connected to the lower end of the crank-connecting rod mechanism, which is used to adjust the opening of the baffle 101a inside the adjustable shrinkage hole 101, a first connecting rod 201b arranged on the electric actuator 201a, a third connecting rod 201c arranged on the first connecting rod 201b, and a second connecting rod 201d arranged on the third connecting rod 201c; the support member 202 includes a pin 202a arranged on the third connecting rod 201c, a support plate 202b arranged on the third connecting rod 201c, and a rotating shaft 202c fixedly connected to the support plate 202b; the connecting rod member 203 includes a fourth connecting rod 203a arranged on the third connecting rod 201c, and a fifth connecting rod 203b arranged on the fourth connecting rod 203a;

[0045] Among them, the right end side of the transmission shaft 101d passes through the bracket and is bonded to the end of the crank-connecting rod mechanism, and the two are movably connected. The bracket is a rectangular semi-open structure, and the opening is welded and connected to the outer frame of the adjustable shrinkage hole 101, which is used to support the entire crank-connecting rod mechanism. The outer wall 102b of one end of the transmission shaft 101d is provided with a crank-connecting rod mechanism 101c, the electric actuator 201a is connected to one end of the first connecting rod 201b, and the other end of the first connecting rod 201b is connected to the third connecting rod 201c, both of which are movably connected, and the other end of the second connecting rod 201d and the middle of the third connecting rod 201c The second connecting rod 201d is connected to the bracket through a pin 202a, the pin 202a is fixedly connected to the bracket, the other end of the second connecting rod 201d and the middle part of the third connecting rod 201c are movably connected to the pin 202a, the two ends of the third connecting rod 201c are respectively connected to the fourth connecting rod 203a, which is a movably connected, the fourth connecting rod 203a is arranged on the upper and lower sides of the support plate 202b, and a plurality of fifth connecting rods 203b are symmetrically connected to the fourth connecting rod 203a, which is a movably connected, and the fifth connecting rod 203b is connected to the rotating shaft 202c that runs through the support plate 202b, which is a fixed connection;

[0046] Among them, a scale can be set in the middle position of the support plate 202b, the scale is fixed on the support plate 202b, the pointer is fixed together with the connecting rod, and when the baffle 101a inside the adjustable shrinkage hole 101 is in a horizontal position, the scale is set to 0, and when the baffle 101a inside the adjustable shrinkage hole 101 is in a vertical position, the scale is set to 100, which is used to indicate the actual opening of the baffle 101a on site.

[0047] During operation, the electric actuator 201a is adjusted to make the crank-connecting rod mechanism drive the transmission shaft 101d to rotate. Through the cooperation of the baffles 101a and the transmission shaft 101d arranged in a row, the size of the gap 102d between the movable leaves is changed, thereby changing the size of the vent flow of the adjustable shrinkage hole 101.

[0048] Example 2

[0049] As a second embodiment of the present invention, an intelligent control system for adjustable shrinkage holes 101 of a coal mill is provided, comprising the following steps:

[0050] like Figure 3 As shown, it includes the electrically adjustable shrinkage hole 101 of the pulverized coal pipe at the outlet of the pulverizer, the wind speed measurement of the air-powder mixture under different working conditions in the pulverized coal pipe, and the automatic wind speed adjustment logic in the DCS, such as Figure 4 As shown, the DCS logic is used to control the amount of air and powder in the pulverized coal pipe by adjusting the shrinkage hole opening under any working condition, ensuring that the maximum wind speed deviation value of each primary air and powder pipe under any working condition corresponds to the deviation value during the experiment, and displays the real-time value.

[0051] After the boiler is put into operation, a combustion condition experiment is carried out, including a pulverizing system experiment. According to the combustion experiment, the air-powder speed at the outlet of each adjustable shrinkage hole 101 under different working conditions will be adjusted. Due to the different resistances, the air-powder speeds of the five pulverized coal pipes corresponding to the burner outlet 20 are different. In order to eliminate the difference and prevent the adjustable shrinkage hole 101 from closing and being unable to adjust, the lowest air-powder speed of combustion commissioning (18-21m / s for the direct-blowing pulverizing system) is used as the benchmark, and the difference K between the benchmark pulverized coal pipe wind speed and the wind speed (air volume) of the other four pulverized coal pipes is set in the DCS logic. Different coal volumes correspond to different The primary air volume is generally controlled at a coal-fired ratio of 2-2.5. The air-powder speed of the benchmark pulverized coal pipe is given by the pulverizer ventilation volume piecewise function F(x), and the air-powder speeds of other pulverized coal pipes are given by the pulverizer ventilation volume piecewise function F(x) and corrected by the ventilation volume (wind speed) difference K. K is the air volume difference (wind speed difference) that ensures the burner outlet wind speed is within the deviation range under different primary air volumes at different coal volumes. The adjustable shrinkage orifice 101 electric regulating valve is automatically adjusted through logical instructions to achieve the wind speed balance at the burner outlet, ensuring stable combustion after the boiler is put into operation and the economy and safety of the boiler operation.

[0052] The different locations of the burners and coal mills, the different lengths of the coal mill outlet coal pulverized pipes and other factors on site lead to different resistances in the coal pulverized pipes. The adjustable shrinkage hole 101 set at the coal mill outlet coal valve and the coal pulverized pipe with the smallest resistance to the burner is logically defined as regulation system 1, the adjustable shrinkage hole 101 set at the coal mill outlet coal valve and the coal pulverized pipe with the smallest resistance to the burner is logically defined as regulation system 2, and so on, the adjustable shrinkage hole 101 set at the coal mill outlet coal valve and the coal pulverized pipe with the largest resistance to the burner is logically defined as regulation system 5;

[0053] Among them, the best data is obtained through experiments, and the air volume difference K is used for correction to control the wind speed of the other four pulverized coal pipes. The resistance is small and the wind speed is fast. To ensure the wind speed of each burner is consistent, the adjustable shrinkage hole 101 valve is closed to the minimum. In order to prevent the output instruction from being 0, resulting in no coal discharge from the pulverized coal pipe, the adjustable shrinkage hole 101 baffle 101a is designed to have a gap when it is fully closed.

[0054] A. Automatic method:

[0055] The set value of the regulating system 1 is set by a piecewise function through the primary air volume of the pulverizing system according to the normal operating test data, and a correction value BIAS1 is reserved for the operator. The actual value of the wind-powder speed 1 is output by the measuring transmitter. By comparing the deviation between the set value and the actual value, PID calculation is performed, and the adjustable shrinkage hole 101 valve 1 instruction of the coal mill outlet is adjusted in real time to achieve precise control of the wind-powder speed.

[0056] (1) The automatic method is as follows:

[0057] Regulation system 1: The wind and powder wind speed is given by the piecewise function F(x) of the ventilation volume of each coal mill, and the set bias BIAS1 received by the operating personnel is used as the set value (S) of the wind and powder wind speed of each mill. The measured value of the wind and powder wind speed is the actual value, which is measured by the wind speed measuring device actually installed on the coal powder pipe (P). The measured value of the wind and powder wind speed is compared with the set value of the wind and powder wind speed converted above in real time, and the wind and powder wind speed is adjusted by outputting the adjustable shrinkage hole 101 valve opening of the coal powder pipe at the outlet of the coal mill from 0% to 100% through PID calculation. When the actual wind and powder wind speed is smaller than the set value of the wind and powder wind speed, the PID automatically outputs a command to gradually increase the adjustable shrinkage hole 101 valve 1. At this time, the measured actual wind speed will gradually increase until it is within the 5% deviation range of the set value. At this time, the valve feedback is consistent with the command, and the adjustable shrinkage hole 101 valve opening is maintained at the current value. In this stable state, the regulation system "exits" regulation. When the actual wind speed is greater than the wind speed setting value, the PID automatically outputs instructions to gradually reduce the opening of the adjustable shrinkage hole 101 valve 1. At this time, the measured actual wind speed will gradually decrease until it is within the 5% deviation range of the set value. At this time, the adjustable shrinkage hole 101 valve feedback is consistent with the instruction, and the adjustable shrinkage hole 101 valve opening is maintained at the current value. In this stable state, the regulation system "exits" regulation. In this way, precise control of the wind speed is achieved).

[0058] Regulation system 2: The air-powder speed is given by the piecewise function F(x) of the ventilation volume of each coal mill (based on the lowest wind speed of the coal powder pipe, which is regulation system 1). F(x) is then corrected by the difference K between the ventilation volume of the coal air pipe and the wind volume (wind speed) of the benchmark coal powder pipe (regulation system 1), and then the operator receives the set bias BIAS2 as the set value (S) of the air-powder speed of each regulation system 2. The measured value of the air-powder speed is the actual value, which is measured by the wind speed measuring device actually installed on the coal powder pipe (P). The measured value of the air-powder speed P is compared in real time with the set value S of the air-powder speed converted above, and the PID operation outputs the adjustable shrinkage hole 101 valve opening of the coal powder pipe at the outlet of the coal mill of 0% to 100%. When the actual wind-powder speed is smaller than the wind-powder speed setting value, the PID automatically outputs instructions to gradually increase the adjustable shrinkage hole 101 valve 2. At this time, the measured actual wind speed will gradually increase until it is within the 5% deviation range from the set value. At this time, the feedback of the adjustment is consistent with the instruction, and the opening of the adjustable shrinkage hole 101 valve is maintained at the current value. When the actual wind-powder speed is larger than the wind-powder speed setting value, the PID automatically outputs instructions to gradually close the adjustable shrinkage hole 101 valve 2. At this time, the measured actual wind speed will gradually decrease until it is within the 5% deviation range from the set value. At this time, the feedback of the adjustable shrinkage hole 101 valve is consistent with the instruction, and the opening of the adjustable shrinkage hole 101 valve is maintained at the current value. In this way, precise control of the wind-powder speed of the pulverized coal pipe is achieved.

[0059] Adjustment systems 3, 4, 5 are the same as adjustment system 2.

[0060] Appendix: Wind speed F(X) function (the functional relationship is obtained through combustion test)

[0061] Primary air volume 0 40 50 60 70 80 90 100 120 Wind speed f(x)

[0062] Note: The set value is a specific segmented value that is preset before the operation of this regulation control logic. It will not change during the regulation control process, but it can be modified online if there is a combustion problem.

[0063] B. Manual method:

[0064] In manual mode, the operating personnel manually and directly output the adjustment valve command through the M / A station of each adjustment system to control the adjustment valve opening; at the same time, the set value is tracked in real time by the BIAS bias module to track the actual value of the wind speed (BAIS tracking value = the difference between the actual wind speed value and the primary air volume F(X) value), and the reference value of the manual input command by the operating personnel is reasonable to achieve manual and automatic disturbance-free switching.

[0065] C. Manual Release Condition (MRE): If any of the following adjustments is met, the adjustment system will automatically switch to manual mode.

[0066] (1) The deviation between the wind speed value set by each adjustment system and the actual wind speed value is large (greater than 20%, which can be set and modified according to the actual situation on site)

[0067] (2) The deviation between the instruction and feedback of the actuator mechanism of each regulating system is large (precision control is greater than 5%, general control is greater than 10%, and it is automatically released)

[0068] (3) Grinding trip signal exists

[0069] 4) Protection Off (PLW): When encountering special working conditions or accidents (any of the following conditions is met), the system automatically exits operation.

[0070] (1) Boiler MFT signal exists

[0071] (2) Grinding trip

[0072] (3) Coal feeder trips

[0073] (4) Failure of grinding air volume measurement point

[0074] (5) Manual method of powder making system

[0075] Operation process: When the adjustable shrinkage hole 101 used in the coal-fired boiler is in use, the intelligent adjustment system in the DCS design automatically adjusts the primary wind speed according to the functional relationship determined by the test under different loads. According to the system's own function of measuring the actual primary wind speed of the pulverized coal pipe, the actual measured value is compared with the system function. In the case of errors, the electric actuator 201a is automatically adjusted to make the crank-connecting rod mechanism drive the transmission shaft 101d to rotate. Through the coordination of the baffles 101a and the transmission shaft 101d arranged in a row, the size of the gap 102d between the movable leaves is changed, thereby changing the size of the ventilation port flow of the adjustable shrinkage hole 101, and then changing the size of the primary wind speed until it is consistent with the system function value. During normal operation, the introduction of sealed air will not cause the accumulation of pulverized coal to affect the normal operation of the coal-fired boiler. The entire adjustable shrinkage hole 101 can be accurately adjusted according to the test data, which is better than the traditional adjustment method.

[0076] Example 3

[0077] As the third embodiment of the present invention, an experimental use process of an intelligent control system of adjustable shrinkage holes 101 of a coal mill is provided, which includes the following contents:

[0078] The A pulverizing system of the company's 600MW unit is used as an example for implementation. The pulverizing system is a HP medium-speed positive pressure direct-blowing pulverizing system. The A layer burner is arranged at the bottom layer of the boiler front wall. From west to east, it is A5, A4, A3, A2, and A1 burners. The A pulverizing system is arranged between 0 meters and 14.7 meters in the furnace. From west to east, it is A1, A2, A3, A4, and A5 pulverized coal pipes. Through the cold combustion test, it is confirmed that the A3 pulverized coal pipe has the smallest resistance (shorter length and curvature), the A5 pulverized coal pipe has the largest resistance (longer length and curvature), and the other three are consistent. The maximum ventilation volume of the pulverizer is designed to be 100T / H, and it can reach up to 120T / H in actual operation.

[0079] The adjustable shrinkage hole 101 of the coal valve at the outlet of the coal mill adopts the shrinkage hole of the electric adjustable baffle 101a of Case 1, and the adjustable shrinkage hole 101 model is SDK-￠ (diameter), with a minimum flow area of ​​30% and a maximum of 100%; the maximum pressure bearing is 0.35MPa; it is connected to the coal powder pipe through a flange. The cable laying and other part designs are consistent with the general others.

[0080] An air-powder online inspection device is designed and installed at the outlet of the adjustable shrinkage hole 101 of the coal mill pulverized coal pipe, and it has a built-in purge function.

[0081] Figure 3In the DCS logic diagram, the corresponding values ​​of the wind and powder speed are as described in Table 1 below. The A3 coal air duct has the smallest resistance, and the corresponding adjustable shrinkage hole 101 is connected to the adjustment system 1. The A5 coal air duct has the largest resistance, and the corresponding adjustable shrinkage hole 101 is connected to the adjustment system 5, and so on. Among them, the proportional gain Kp = 0.8, TI = 120, K2 = 2.5, K3 = 3, K4 = 3.5, K5 = 3.8.

[0082] Table 1 Wind speed F(X) function under different working conditions

[0083]

[0084] After being put into operation, the adjustable shrinkage hole 101 intelligent adjustment system is automatically adjusted in real time under different boiler working conditions. The collected parameters are shown in Figure 6 . Under different coal quantities and different air volumes, different air-powder speeds are adjusted in real time. This ensures the consistency of the coal powder speed at the burner outlet under different loads, ensuring the best combustion conditions.

[0085] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements, as well as parameter values, mounting arrangements, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure described herein that performs the function, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, improvements, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to numerous modifications still falling within the scope of the appended claims.

[0086] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.

[0087] It should be understood that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but for those of ordinary skill having the benefit of this disclosure, without undue experimentation, the development effort will be a routine task of design, fabrication, and production.

[0088] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. An adjustable shrinkage hole for a coal mill, characterized in that: include, An adjustment component (100) comprises an adjustable shrinkage hole (101), a component (102) and a gas component (103), wherein the component (102) is arranged on the adjustable shrinkage hole (101), and the gas component (103) is arranged on the adjustable shrinkage hole (101); and The control component (200) comprises an output member (201), a support member (202) and a connecting rod member (203), wherein the output member (201) is arranged on the adjustable shrinkage hole (101), the support member (202) is arranged on the output member (201), and the connecting rod member (203) is arranged on the support member (202).

2. The adjustable shrinkage hole of coal mill according to claim 1, characterized in that: The adjustable shrinkage hole (101) comprises a baffle (101a) arranged on the inner side of the adjustable shrinkage hole (101), a fixed bracket (101b) arranged on the outer side, a crank connecting rod mechanism arranged at the center of the fixed bracket (101b), and a transmission shaft (101d) arranged on the inner side of the baffle (101a).

3. The adjustable shrinkage hole of coal mill according to claim 2, characterized in that: The component (102) includes the transmission shaft (101d) whose left and right ends are embedded in the inner wall (102a) of the adjustable shrinkage hole (101), the right end of the transmission shaft (101d) passes through the outer wall (102b) of the adjustable shrinkage hole (101), the inner wall (102a) and the outer wall (102b) are both provided with a hollow layer (102c), and a gap (102d) is provided between the baffles (101a).

4. The adjustable shrinkage hole of coal mill according to claim 2 or 3, characterized in that: The gas component (103) comprises a pipeline (103a) arranged on the adjustable shrinkage hole (101), and an isolation door (103b) arranged on the pipeline (103a).

5. The adjustable shrinkage hole of coal mill according to claim 4, characterized in that: The output member (201) comprises an electric actuator (201a) arranged at the lower end of the crank-connecting rod mechanism, a first connecting rod (201b) arranged on the electric actuator (201a), a third connecting rod (201c) arranged on the first connecting rod (201b), and a second connecting rod (201d) arranged on the third connecting rod (201c).

6. The adjustable shrinkage hole of coal mill according to claim 5, characterized in that: The support member (202) comprises a pin (202a) arranged on the third connecting rod (201c), a bracket arranged on the third connecting rod (201c), and a rotating shaft (202c) arranged on the bracket.

7. The adjustable shrinkage hole of coal mill according to claim 6, characterized in that: The connecting rod member (203) comprises a fourth connecting rod (203a) arranged on the third connecting rod (201c), and a fifth connecting rod (203b) arranged on the fourth connecting rod (203a).

8. An intelligent control system for adjustable shrinkage holes in a coal mill, characterized in that: The method comprises the adjustable shrinkage hole of a coal mill as claimed in any one of claims 1 to 7, comprising the following steps: Through DCS logic, the amount of air and powder in the pulverized coal pipe can be controlled by adjusting the shrinkage hole opening under any working conditions; According to the combustion experiment, the air-powder velocity at the outlet of each adjustable shrinkage hole (101) under different working conditions is adjusted; Use manual mode and protection shutdown function to automatically exit operation in case of special working conditions or accidents.

9. The intelligent control system for adjustable shrinkage holes of coal mill according to claim 8, characterized in that: The wind speed automatic adjustment logic in the DCS includes the setting of the reference coal powder pipe wind speed setting and the setting of the wind speed difference K of the other four coal powder pipes. Different coal quantities correspond to different primary air volumes. Generally, the air-coal ratio is controlled between 2-2.

5. When the actual air-powder wind speed is smaller than the air-powder wind speed setting value, the PID automatically outputs a command to gradually open the adjustable shrinkage orifice (101) regulating valve; when the actual air-powder wind speed is larger than the air-powder wind speed setting value, the PID automatically outputs a command to gradually close the adjustable shrinkage orifice (101) regulating valve.

10. The intelligent control system for adjustable shrinkage holes of coal mill according to claim 9, characterized in that: In manual mode, the operating personnel directly output the adjustment valve command manually through the M / A station of each adjustment system to control the adjustment valve opening; at the same time, the set value tracks the actual value of the wind powder speed in real time through the BIAS bias module (BAIS tracking value = the difference between the actual wind speed value and the primary air volume F(X) value), and the protection shutdown function is used to automatically exit operation in the event of special working conditions or accidents.

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