A method, system, device and medium for medium-speed coal mill dynamic separator failure without stopping grinding

Abstract

The application discloses a kind of medium-speed coal mill dynamic separator fault under no grinding method, system, equipment and medium, method includes obtaining the relevant parameter of dynamic separator in medium-speed coal mill, whether the dynamic separator is judged to occur fault based on relevant parameter;If it is determined to occur fault, the medium-speed coal mill and associated system of sending fault are executed collaborative adjustment, collaborative adjustment includes fault initial control stage and stable period optimization stage;Fault initial control stage includes to the parameter of fault medium-speed coal mill, burner swing angle and superheater desuperheating water device and steam turbine admission control gate control;Stable period optimization stage includes after the dynamic separator reaches stable state, adjustment coal mill output.The application does not need to shut down fault coal mill and start standby coal mill, avoids the loss caused by short time drop of boiler evaporation capacity and load recovery time consumption, improves the economy under the operation of separator fault, realizes the on-line repair of separator under the condition of no outage coal mill.

Description

Technical Field

[0001] This invention relates to the field of coal mill technology, and in particular to a method, system, equipment and medium for continuous grinding in the event of a failure of the dynamic separator in a medium-speed coal mill. Background Technology

[0002] In the field of thermal power generation, medium-speed coal mill direct-fired pulverizing systems are widely used in drum boiler units due to their high efficiency and fast response. Their operational stability directly affects the boiler's evaporation rate, heating load, and power generation efficiency. The dynamic separator, as a core component of the medium-speed coal mill, plays a crucial role in regulating and separating pulverized coal fineness. Its normal operation ensures uniform pulverized coal particle size entering the furnace, guaranteeing complete combustion and stable boiler parameters. With the expansion of unit capacity and the extension of operating time, dynamic separator failures due to wear of transmission components, motor malfunctions, and frequency converter abnormalities occur frequently, becoming a significant factor restricting the continuous and stable operation of the unit.

[0003] However, when the dynamic separator malfunctions, the traditional approach is to shut down the faulty coal mill and start the backup one. This method results in a significant drop in boiler evaporation within a short period, reducing it by 120-130 t / h in a 60MW back-pressure unit. The unit load recovery takes approximately one hour, causing significant losses in electrical and heating loads, approximately 14MW of electrical load and 61t of heating load. If the coal mill is kept running, the separator malfunction will worsen the coal powder separation effect, leading to increased mill vibration, superheater wall overheating, and main steam pipeline overpressure, creating a technical contradiction: shutting down the mill results in reduced efficiency, while continuing operation increases safety risks. A solution that balances safety and economy is urgently needed. Summary of the Invention

[0004] In view of the aforementioned existing problems, the present invention is proposed.

[0005] Therefore, this invention provides a method for continuous grinding in the event of a fault in the dynamic separator of a medium-speed coal mill, which solves the problems of reduced output when grinding is stopped and increased equipment vibration and overheating of the superheater wall when grinding is continued.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] In a first aspect, the present invention provides a method for continuous milling under conditions of dynamic separator failure in a medium-speed coal mill, comprising:

[0008] Obtain relevant parameters of the dynamic separator in the medium-speed coal mill, and determine whether the dynamic separator has malfunctioned based on the relevant parameters;

[0009] If a fault is determined to have occurred, a coordinated adjustment is performed on the medium-speed coal mill that sent the fault and its associated systems. The coordinated adjustment includes an initial fault control phase and a stable period optimization phase.

[0010] The initial control phase of the fault includes controlling the parameters of the faulty medium-speed coal mill, the burner swing angle, the superheater desuperheating water device, and the turbine inlet steam regulating valve.

[0011] The stabilization optimization phase includes adjusting the output of the coal mill after the dynamic separator reaches a stable state.

[0012] As a preferred embodiment of the method for continuous mill operation under fault conditions of the dynamic separator in a medium-speed coal mill according to the present invention, the method includes: obtaining relevant parameters of the dynamic separator in the medium-speed coal mill, and determining whether the dynamic separator has malfunctioned based on the relevant parameters, including:

[0013] The operating parameters of the dynamic separator are obtained, including separator current, separator speed and inverter frequency. When the separator current exceeds the normal value by 30% or either the separator speed or the inverter frequency is lower than the set value by 30%, the dynamic separator is determined to be faulty.

[0014] As a preferred embodiment of the method for continuous mill operation under fault conditions of the dynamic separator in a medium-speed coal mill according to the present invention, the control of parameters of the faulty medium-speed coal mill includes:

[0015] By reducing the grinding force of the medium-speed coal mill, the rapid thinning of the coal bed inside the medium-speed coal mill can be suppressed, while maintaining the coal feed rate of the medium-speed coal mill within the coal feed range to avoid excessive vibration caused by excessively low coal feed rate.

[0016] The vibration magnitude of a medium-speed coal mill is affected by the coal feed rate, grinding force, and coal grindability. When maintaining a certain basic coal feed rate, if the coal grindability is good, the hydraulic loading oil pressure drop of the medium-speed coal mill can be further increased during adjustment.

[0017] As a preferred embodiment of the method for continuous mill operation under dynamic separator failure in a medium-speed coal mill according to the present invention, the method includes controlling the burner swing angle, comprising:

[0018] By reducing the downward swing of the burner from a horizontal position, the primary air flow rate at the coal mill inlet is increased. By increasing the primary air volume, the residence time of pulverized coal in the furnace is extended. In conjunction with the burner angle adjustment, the flame center in the furnace is lowered, the heat load at the superheater inlet is reduced, and the risk of superheater overheating is reduced.

[0019] Increase the primary air volume of the medium-speed coal mill by 5%.

[0020] As a preferred embodiment of the method for continuous mill operation under dynamic separator failure in a medium-speed coal mill according to the present invention, the control of the superheater desuperheating water device and the turbine inlet steam regulating valve includes:

[0021] Increasing the opening of the superheater desuperheating water regulating valve, delaying the opening of the turbine inlet steam regulating valve, reducing the superheater steam-side temperature, and increasing the superheater steam-side flow rate can improve the superheater cooling effect and reduce the risk of superheater overheating.

[0022] As a preferred embodiment of the method for continuous mill operation under fault conditions of the dynamic separator in a medium-speed coal mill as described in this invention, the initial fault control stage further includes:

[0023] For other coal mills operating in the unit, the grinding force of the coal mills is reduced by increasing the separator speed, and the total coal feed rate is reduced by 10%.

[0024] Reduce the amount of coal fed into the furnace from other pulverizing systems, increase the air volume of the blower, balance the problem of the separator tripping and the instantaneous increase in the amount of coal fed into the pulverizer and the decrease in the air-coal ratio, and quickly bring the oxygen content at the furnace outlet back to the normal range.

[0025] As a preferred embodiment of the method for continuous mill operation under fault conditions of the dynamic separator in a medium-speed coal mill according to the present invention, the stabilization optimization stage includes adjusting the output of the coal mill after the dynamic separator reaches a stable state, including:

[0026] When the vibration of the medium-speed coal mill is less than or equal to the vibration threshold, the superheater wall temperature has a large margin compared to the over-temperature threshold, the inlet and outlet differential pressure of the medium-speed coal mill, the boiler load and furnace oxygen content are relatively stable, the mill enters the stable period optimization stage. The core objective of the stable period optimization stage is to improve economic efficiency within the safety boundary.

[0027] Once the coal bed thickness of the faulty medium-speed coal mill stabilizes, increase the output of other coal mills to restore the unit output to normal levels and ensure that the heating load is not reduced.

[0028] Provided that the superheater temperature does not exceed the design value, the desuperheating water regulating valve is gradually closed, and the burner swing angle is finely adjusted to raise the main steam temperature to within ±2℃ of the design value, thereby reducing the power generation efficiency loss caused by low steam temperature.

[0029] Secondly, the present invention provides a system for continuous mill operation under dynamic separator failure in a medium-speed coal mill, comprising:

[0030] The data acquisition and judgment module is used to acquire relevant parameters of the dynamic separator in the medium-speed coal mill, and to determine whether the dynamic separator has failed based on the relevant parameters. If a failure is determined, the module performs coordinated adjustment on the medium-speed coal mill that sent the failure and the associated system. The coordinated adjustment includes an initial failure control phase and a stable period optimization phase.

[0031] The fault adjustment module is used in the initial fault control phase, including controlling the parameters of the faulty medium-speed coal mill, the burner swing angle, the superheater desuperheating water device, and the turbine inlet steam regulating valve.

[0032] The fault secondary adjustment module is used to adjust the output of the coal mill after the dynamic separator reaches a stable state during the stabilization period optimization phase.

[0033] Thirdly, the present invention provides an electronic device, comprising:

[0034] Memory and processor;

[0035] The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions. When the computer-executable instructions are executed by the processor, the steps of the method for continuous grinding under the fault of the dynamic separator of the medium-speed coal mill are implemented.

[0036] Fourthly, the present invention provides a computer-readable storage medium storing computer-executable instructions that, when executed by a processor, implement the steps of the method for continuous milling under fault conditions of the dynamic separator of the medium-speed coal mill.

[0037] Compared with existing technologies, the advantages of this invention are as follows: This invention achieves continuous and stable operation of the coal mill with output even when the dynamic separator fails, through multi-parameter coordinated control. This ensures that the main steam flow does not decrease, the main steam pipeline does not experience overpressure, the superheater does not overheat, and the coal mill vibration remains within a safe range. It eliminates the need to shut down the faulty coal mill and start a backup coal mill, avoiding the loss of heating load and power generation caused by a significant short-term drop in boiler evaporation and the time required for load recovery, thus improving the economic efficiency of operation under separator failure. It enables online maintenance of the separator without shutting down the coal mill, allowing for tasks such as drive belt replacement and adjustment, motor maintenance, frequency converter maintenance, and oil circuit unblocking, overcoming the technical difficulty of traditional maintenance requiring mill shutdown. It adopts a phased strategy of prioritizing safety before improving efficiency, quickly suppressing parameter fluctuations in the initial stage of a fault and optimizing adjustments within safe boundaries during the stable period, balancing equipment safety and operational efficiency. Furthermore, the operation process is clear, highly controllable, and easy to apply and promote in practice. Attached Figure Description

[0038] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1This is a schematic diagram of the overall process of the method for continuous grinding under the fault of dynamic separator in medium-speed coal mill according to an embodiment of the present invention. Detailed Implementation

[0040] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0041] Example 1, referring to Figure 1 Table 1 illustrates an embodiment of the present invention, providing a method for continuous mill operation under dynamic separator failure in a medium-speed coal mill, comprising:

[0042] S1: Obtain relevant parameters of the dynamic separator in the medium-speed coal mill, and determine whether the dynamic separator has malfunctioned based on the relevant parameters;

[0043] Preferably, the operating parameters of the dynamic separator are obtained, including separator current, separator speed and inverter frequency. When the separator current exceeds the normal value by 30% or either the separator speed or the inverter frequency is lower than the set value by 30%, the dynamic separator is determined to have malfunctioned.

[0044] Optionally, the operating parameters of the dynamic separator may also include speed, motor current, drive belt tension, inverter output frequency, etc.

[0045] It should be noted that, in addition to operating parameters, there are other factors that can cause large vibrations in medium-speed mills. For example, hard foreign objects such as metal may enter the mill, or there may be a failure in the mill roller bearings, or the fineness of the coal powder at the outlet of the medium-speed mill may change. These factors can be combined to make a judgment.

[0046] Optionally, the preset thresholds for each parameter can be set as follows: dynamic separator speed deviates from the rated value by ±10%, motor current exceeds the rated value by 15%, coal mill vibration value >0.08mm, coal powder fineness R90 >30%, etc.; the specific thresholds for each parameter can be adjusted according to the unit model and operating standards.

[0047] It should be noted that by acquiring the above parameters and judging the threshold, the fault status of the dynamic separator can be quickly and accurately identified, avoiding load loss caused by improper operation due to misjudgment of faults, or equipment safety risks caused by missed faults. This provides a reliable basis for subsequent coordinated adjustments and ensures the timeliness and pertinence of fault handling.

[0048] S2: If a fault is determined to have occurred, a coordinated adjustment is performed on the medium-speed coal mill that sent the fault and its associated systems. The coordinated adjustment includes the initial fault control phase and the stable period optimization phase.

[0049] S2-1: The initial control phase of the fault includes controlling the parameters of the faulty medium-speed coal mill, the burner swing angle, the superheater desuperheating water device, and the turbine inlet steam regulating valve.

[0050] Preferably, the parameters of the faulty medium-speed coal mill are controlled, including:

[0051] By reducing the grinding force of the medium-speed coal mill, the rapid thinning of the coal bed inside the medium-speed coal mill can be suppressed, while maintaining the coal feed rate of the medium-speed coal mill within the coal feed range to avoid excessive vibration caused by excessively low coal feed rate.

[0052] The vibration magnitude of a medium-speed coal mill is affected by the coal feed rate, grinding force, and coal grindability. When maintaining a certain basic coal feed rate, if the coal grindability is good, the hydraulic loading oil pressure drop of the medium-speed coal mill can be further increased during adjustment.

[0053] Specifically, the grinding force of the coal mill and the coal feed rate are controlled in a coordinated manner. The "sudden drop in grinding force of the coal mill + maintenance of basic coal feed rate" is immediately implemented. By significantly reducing the grinding force of the coal mill, the rapid thinning of the coal bed inside the coal mill is suppressed. Optionally, the hydraulic loading oil pressure is reduced from 6.2MPa to 2.8MPa, a reduction of about 55%.

[0054] Simultaneously, maintain the coal feed rate of the coal mill within a reasonable range, for example, reducing it from 19.5t to 17t / h, but not lower than 16t / h, to avoid excessive vibration caused by an excessively low feed rate. This also effectively suppresses a large amount of pulverized coal entering the furnace in a short period of time. After the above adjustments, the vibration of the coal mill can be controlled below 0.08mm. The specific reduction in grinding force and coal quantity should meet the vibration safety standards of the plant's coal mill. Table 1 shows the upper limit of vibration control values ​​for rotating machinery in the industry. If the manufacturer has no special provisions, the standards in the table below can be followed.

[0055] Table 1. Upper Limits of Vibration Control Values ​​for Rotating Machinery in the Industry

[0056]

[0057]

[0058] Under this operating condition, the magnitude of the coal mill vibration is affected by the coal feed rate, the grinding force of the coal mill, and the grindability of the coal. Under the premise of maintaining a certain basic coal feed rate, if the grindability of the coal is good, the hydraulic loading oil pressure reduction of the coal mill can be further increased during the adjustment to ensure that the vibration of the coal mill meets the safety specifications.

[0059] Preferably, controlling the burner tilt angle includes:

[0060] By reducing the downward swing of the burner from a horizontal position, the primary air flow rate at the coal mill inlet is increased. By increasing the primary air volume, the residence time of pulverized coal in the furnace is extended. In conjunction with the burner angle adjustment, the flame center in the furnace is lowered, the heat load at the superheater inlet is reduced, and the risk of superheater overheating is reduced.

[0061] Increase the primary air volume of the medium-speed coal mill by 5%.

[0062] Specifically, for flame combustion center control, the burner tilt angle is lowered from 50% horizontal to 40% within approximately 5-10 seconds. Simultaneously, the primary air flow rate at the pulverizer inlet is appropriately increased. This increases the primary air volume, prolonging the residence time of pulverized coal in the furnace. Combined with the burner tilt angle adjustment, this lowers the flame center within the furnace, reducing the heat load at the superheater inlet and mitigating the risk of superheater overheating. However, excessively increasing the primary air flow rate can further thin the coal bed and exacerbate pulverizer vibration. Based on experience, increasing the primary air flow rate by approximately 5% is generally recommended.

[0063] Preferably, the control of the superheater desuperheating water device and the turbine inlet steam regulating valve includes:

[0064] Increasing the opening of the superheater desuperheating water regulating valve, delaying the opening of the turbine inlet steam regulating valve, reducing the superheater steam-side temperature, and increasing the superheater steam-side flow rate can improve the superheater cooling effect and reduce the risk of superheater overheating.

[0065] Specifically, the superheater desuperheating water and the turbine control valve are controlled in a coordinated manner. The superheater desuperheating water control valve is opened simultaneously, for example, by increasing the opening by 20%-30%, and the turbine inlet steam control valve is opened with a delay to increase the steam flow by about 2% of the rated evaporation capacity. This achieves the effect of reducing the steam side temperature of the superheater and increasing the steam side flow of the superheater, thereby improving the superheater cooling effect and reducing the risk of superheater overheating.

[0066] The reason for delaying the opening of the turbine inlet regulating valve is that opening it too wide causes a rapid drop in the saturated steam pressure in the steam drum, triggering flash evaporation of some of the working fluid and increasing the main steam flow. However, this increase is unsustainable, typically lasting only 3-5 minutes, mainly influenced by the boiler drum volume. If the valve is opened too early, the superheated water wall temperature is still rising, and the increased flow has already been released, failing to fully utilize the cooling effect from the increased working fluid flow and missing a more effective opportunity. In actual control, the main steam header pressure rises by approximately 0.2-0.3 MPa, less than 3%. The high-temperature superheater wall temperature, most prone to overheating, rises by a maximum of about 8°C in about 4 minutes, leaving a 6°C safety margin before exceeding the overheating threshold.

[0067] Preferably, the initial fault control phase also includes:

[0068] For other coal mills operating in the unit, the grinding force of the coal mills is reduced by increasing the separator speed, and the total coal feed rate is reduced by 10%.

[0069] Reduce the amount of coal fed into the furnace from other pulverizing systems, increase the air volume of the blower, balance the problem of the separator tripping and the instantaneous increase in the amount of coal fed into the pulverizer and the decrease in the air-coal ratio, and quickly bring the oxygen content at the furnace outlet back to the normal range.

[0070] Specifically, other pulverizing systems and air supply volume are adjusted in coordination. For other operating coal mills in the unit, the coal powder separation effect is enhanced by increasing their separator speed, the grinding force of the coal mill is appropriately reduced, and the total coal feed is reduced by 10%, approximately 8 tons of coal. The amount of coal fed into the furnace by other pulverizing systems is reduced in a short period of time, and the air supply volume of the blower is appropriately increased to balance the problem of the instantaneous increase in the amount of coal fed into the furnace by the separator tripping and the decrease in the air-coal ratio. The oxygen content at the furnace outlet is quickly brought back to the normal range of 2%-5%.

[0071] Optionally, by promptly opening the turbine inlet steam regulating valve and reducing the amount of coal fed into the furnace from the standby and faulty coal mills, the overpressure problem in the main steam pipeline can also be effectively suppressed. The main steam generated by the abnormal separator can be transferred to the deaerator after being used by the turbine, thus preventing the turbine exhaust pressure from rising.

[0072] It should be noted that the above-mentioned coordinated control steps have no fixed order and are recommended to be implemented simultaneously. Through the above rapid response operations, the trend of rapid coal seam thinning and flame center shifting upward can be curbed within 3-5 minutes, effectively preventing increased vibration of the coal mill, superheater overheating, and main steam pipeline overpressure, thus creating conditions for entering the stable phase.

[0073] It should also be noted that dynamic separator failure can lead to decreased coal powder separation efficiency, increased pulverizer vibration, and increased risk of superheater overheating, requiring a multi-dimensional parameter adjustment system to address these issues. This invention reduces the pulverizer grinding force while maintaining the basic coal feed rate, thus preventing excessive vibration caused by rapid coal bed thinning. Adjusting the burner sway angle and primary air flow can lower the flame center to reduce the superheater heat load. Coordinated control of the desuperheating water regulating valve and the turbine inlet steam regulating valve can enhance the superheater cooling effect through coordinated regulation of working fluid flow and temperature, and delayed opening of the turbine regulating valve can prevent flash flow waste. Simultaneous adjustment of other pulverizing system parameters and air volume can balance the furnace air-coal ratio and maintain stable combustion. These measures, implemented simultaneously, can quickly curb parameter fluctuations within 3-5 minutes, control the pulverizer vibration below 0.08mm, ensure the main steam pressure rise does not exceed 3%, and maintain the superheater wall temperature safety margin above 6℃. This effectively avoids equipment safety risks and lays the foundation for subsequent optimization during the stabilization period. It achieves safe and controllable operation of the pulverizer without interruption in the event of a fault, overcoming the load loss problem caused by traditional mill shutdowns.

[0074] S2-2: The stabilization period optimization stage includes adjusting the output of the coal mill after the dynamic separator reaches a stable state;

[0075] Preferably, when the vibration of the medium-speed coal mill is less than or equal to the vibration threshold, the superheater wall temperature has a large margin compared to the over-temperature threshold, the inlet and outlet differential pressure of the medium-speed coal mill, the boiler load and the oxygen content in the furnace are relatively stable, the mill enters the stable period optimization stage. The core objective of the stable period optimization stage is to improve economic efficiency within the safety boundary.

[0076] Preferably, once the coal bed thickness of the faulty medium-speed coal mill stabilizes, the output of other coal mills is increased to restore the unit output to normal levels, ensuring that the heating load is not reduced.

[0077] Preferably, provided that the superheater temperature does not exceed the design value, the desuperheating water regulating valve is gradually closed, and the burner sway angle is finely adjusted to raise the main steam temperature to within ±2℃ of the design value, thereby reducing the power generation efficiency loss caused by low steam temperature.

[0078] Optionally, depending on the height of the coal mill where the separator trips and the different volatile matter content of the coal, the adjustment range should be appropriately increased or decreased, including the air supply volume, the steam turbine inlet regulating valve, the burner swing angle, the primary air flow of the faulty coal mill, and the superheater desuperheating water. Generally speaking, the lower the volatile matter content and the higher the coal mill, the greater the adjustment range.

[0079] Specifically, this stage begins when the coal mill vibration is ≤0.06mm, the superheater wall temperature has a large margin (generally above 8℃) above the over-temperature threshold, the coal mill inlet and outlet differential pressure, boiler load, and furnace oxygen content are relatively stable. The core objective is to improve economic efficiency within the safety boundary.

[0080] Load and heating restoration: Once the coal bed thickness of the faulty coal mill stabilizes, the output of other coal mills should be appropriately increased to restore the unit output to normal levels and ensure that the heating load does not decrease. Generally, the fuel quantity should be restored within 6 minutes after the anomaly occurs, which can basically ensure that the boiler evaporation does not decrease.

[0081] Main steam temperature optimization: Under the premise that the superheater temperature does not exceed the design value, gradually close the desuperheating water regulating valve (close it by 5% each time, observe for 5 minutes and adjust it again after there is no trend of overheating), and at the same time fine-tune the burner swing angle (swing it up by 2%-3% each time) to raise the main steam temperature to the design value ±2℃ range, thereby reducing the power generation efficiency loss caused by low steam temperature.

[0082] After entering the stable optimization phase, once the main parameters of the unit and the operation of the equipment are stable, the separator can be powered off before carrying out specific maintenance work on the dynamic separator of the coal mill. If the inspection results indicate that the separator bearings or the separator body and other structures located inside the coal mill need to be repaired, the coal mill still needs to be shut down before proceeding.

[0083] This invention forms a closed-loop control by balancing the overall operating conditions through collaborative control logic, a system-level solution not adopted in existing technologies. Practical data shows that during the stabilization period, a gradual adjustment of 10-20 minutes can restore the unit's original load and bring the main steam temperature back to the design value while ensuring that safety indicators such as vibration and over-temperature meet the standards, thus balancing safety and economy.

[0084] It should be noted that,

[0085] Example 2 illustrates a schematic scheme for a method to continue grinding in the event of a failure of the dynamic separator in a medium-speed coal mill. It should be noted that the technical solution of this system for continuing grinding in the event of a failure of the dynamic separator in a medium-speed coal mill belongs to the same concept as the technical solution of the method for continuing grinding in the event of a failure of the dynamic separator in a medium-speed coal mill described above. Details not described in detail in this embodiment can be found in the description of the technical solution of the method for continuing grinding in the event of a failure of the dynamic separator in a medium-speed coal mill described above.

[0086] This invention achieves uninterrupted and stable operation of the coal mill with output even when the dynamic separator fails, through multi-parameter coordinated control. This ensures that the main steam flow does not decrease, the main steam pipeline does not experience overpressure, the superheater does not overheat, and the coal mill vibration remains within safe limits. It eliminates the need to shut down the faulty coal mill and start a backup mill, avoiding the loss of heating load and power generation caused by a significant short-term drop in boiler evaporation and the time required for load recovery, thus improving the economic efficiency of operation under separator failure conditions. It also enables online maintenance of the separator without shutting down the coal mill, allowing for tasks such as drive belt replacement and adjustment, motor maintenance, frequency converter maintenance, and oil circuit unblocking, overcoming the technical difficulty of traditional maintenance requiring mill shutdown. Adopting a phased strategy of prioritizing safety before improving efficiency, it quickly suppresses parameter fluctuations in the initial stage of a failure and optimizes adjustments within safe boundaries during the stable period, balancing equipment safety and operational efficiency. Furthermore, the operation process is clear, highly controllable, and easy to apply and promote in practice.

[0087] It should be noted that after the dynamic separator trips, the coal powder separation effect in the coal mill deteriorates, the proportion of coarse powder at the separator outlet increases, the fineness of the coal powder is unqualified, and the combustion speed of the coal powder after it is sent to the furnace is slower, making it difficult to burn fully in a limited time and space, resulting in a decrease in boiler efficiency. Taking Huaneng Nanjing Thermal Power as an example, after the separation of the middle layer coal mill causes it to trip, the boiler efficiency decreases by about 0.5%.

[0088] Due to the large size and high hardness of the coarse powder particles, they will cause certain erosion and wear on the coal mill outlet air-coal pipeline, resulting in thinning of the pipeline wall, especially at bends.

[0089] Based on the above two considerations, the method for maintaining continuous operation of the medium-speed coal mill in this invention is applicable when the separator failure can be quickly restored to operation. If the maintenance time exceeds 4 hours, it is recommended to switch to the standby coal mill.

[0090] This embodiment also provides a system for continuous mill operation under dynamic separator failure in a medium-speed coal mill, including:

[0091] The data acquisition and judgment module is used to acquire relevant parameters of the dynamic separator in the medium-speed coal mill and determine whether the dynamic separator has failed based on the relevant parameters. If a failure is determined, coordinated adjustment is performed on the medium-speed coal mill that sent the failure and the associated system. The coordinated adjustment includes the initial control stage of the failure and the optimization stage of the stable period.

[0092] The fault adjustment module is used in the initial fault control phase, including controlling the parameters of the faulty medium-speed coal mill, burner swing angle, superheater desuperheating water device and turbine inlet steam regulating valve.

[0093] The fault secondary adjustment module is used during the stable period optimization phase, including adjusting the output of the coal mill after the dynamic separator reaches a stable state.

[0094] This embodiment also provides an electronic device suitable for continuous grinding in the event of a failure of the dynamic separator in a medium-speed coal mill, comprising: a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions to realize the method for continuous grinding in the event of a failure of the dynamic separator in a medium-speed coal mill as proposed in the above embodiment.

[0095] This embodiment also provides a storage medium storing a computer program that, when executed by a processor, implements the method for continuous grinding under fault conditions of a dynamic separator in a medium-speed coal mill, as proposed in the above embodiments.

[0096] The storage medium proposed in this embodiment and the method for implementing continuous grinding under the fault of dynamic separator in medium-speed coal mill proposed in the above embodiment belong to the same inventive concept. Technical details not described in detail in this embodiment can be found in the above embodiments, and this embodiment has the same beneficial effects as the above embodiments.

[0097] Based on the above description of the implementation methods, those skilled in the art will clearly understand that the present invention can be implemented using software and necessary general-purpose hardware, and of course, it can also be implemented using hardware. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk, or optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods of the various embodiments of the present invention.

[0098] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for continuous milling under dynamic separator failure in a medium-speed coal mill, characterized in that, include: Obtain relevant parameters of the dynamic separator in the medium-speed coal mill, and determine whether the dynamic separator has malfunctioned based on the relevant parameters; If a fault is determined to have occurred, a coordinated adjustment is performed on the medium-speed coal mill that sent the fault and its associated systems. The coordinated adjustment includes an initial fault control phase and a stable period optimization phase. The initial control phase of the fault includes controlling the parameters of the faulty medium-speed coal mill, the burner swing angle, and the superheater desuperheating water device and the turbine inlet steam regulating valve. The initial fault control phase includes: Controlling the parameters of the faulty medium-speed coal mill includes reducing the grinding force of the medium-speed coal mill to inhibit the rapid thinning of the coal bed inside the medium-speed coal mill, while maintaining the coal feed rate of the medium-speed coal mill within the preset coal feed range. Controlling the burner sway angle includes reducing the downward sway of the burner from a horizontal state and increasing the primary air flow rate at the coal mill inlet; Control the superheater desuperheating water device and the turbine inlet steam regulating valve, including increasing the opening of the superheater desuperheating water regulating valve and delaying the opening of the turbine inlet steam regulating valve; The stabilization optimization phase includes adjusting the output of the coal mill after the dynamic separator reaches a stable state.

2. The method for continuous mill operation under dynamic separator failure in a medium-speed coal mill as described in claim 1, characterized in that, Obtain relevant parameters of the dynamic separator in a medium-speed coal mill, and determine whether the dynamic separator has malfunctioned based on the relevant parameters, including: The operating parameters of the dynamic separator are obtained, including separator current, separator speed and inverter frequency. When the separator current exceeds the normal value by 30% or either the separator speed or the inverter frequency is lower than the set value by 30%, the dynamic separator is determined to be faulty.

3. The method for continuous mill operation under dynamic separator failure in a medium-speed coal mill as described in claim 2, characterized in that, Controlling the parameters of the faulty medium-speed coal mill includes: By reducing the grinding force of the medium-speed coal mill, the rapid thinning of the coal bed inside the medium-speed coal mill is suppressed, while maintaining the coal feed rate of the medium-speed coal mill within the coal feed range, so as to avoid excessive vibration caused by excessively low coal feed rate. The vibration magnitude of a medium-speed coal mill is affected by the coal feed rate, grinding force, and coal grindability. When maintaining a certain basic coal feed rate, if the coal grindability is good, the hydraulic loading oil pressure drop of the medium-speed coal mill can be further increased during adjustment.

4. The method for continuous mill operation under dynamic separator failure in a medium-speed coal mill as described in claim 3, characterized in that, Controlling the burner tilt angle includes: By reducing the downward swing of the burner from a horizontal position, the primary air flow rate at the coal mill inlet is increased. By increasing the primary air volume, the residence time of pulverized coal in the furnace is extended. In conjunction with the burner angle adjustment, the flame center in the furnace is lowered, the heat load at the superheater inlet is reduced, and the risk of superheater overheating is reduced. Increase the primary air volume of the medium-speed coal mill by 5%.

5. The method for continuous mill operation under dynamic separator failure in a medium-speed coal mill as described in claim 4, characterized in that, Controlling the superheater desuperheating water system and the turbine inlet steam regulating valve, including: Increasing the opening of the superheater desuperheating water regulating valve, delaying the opening of the turbine inlet steam regulating valve, reducing the superheater steam-side temperature, and increasing the superheater steam-side flow rate can improve the superheater cooling effect and reduce the risk of superheater overheating.

6. The method for continuous mill operation under dynamic separator failure in a medium-speed coal mill as described in claim 1, characterized in that, The initial control phase of a fault also includes: For the other coal mills operating in the unit, the grinding force of the coal mills is reduced by increasing the separator speed, and the total coal feed rate is reduced by 10%. Reduce the amount of coal fed into the furnace from other pulverizing systems, increase the air volume of the blower, balance the problem of the separator tripping and the instantaneous increase in the amount of coal fed into the pulverizer and the decrease in the air-coal ratio, and quickly bring the oxygen content at the furnace outlet back to the normal range.

7. The method for continuous mill operation under dynamic separator failure in a medium-speed coal mill as described in claim 6, characterized in that, The stabilization optimization phase includes adjusting the output of the coal mill after the dynamic separator reaches a stable state, including: When the vibration of the medium-speed coal mill is less than or equal to the vibration threshold, the superheater wall temperature has a large margin compared to the over-temperature threshold, the inlet and outlet differential pressure of the medium-speed coal mill, the boiler load and furnace oxygen content are relatively stable, the mill enters the stable period optimization stage. The core objective of the stable period optimization stage is to improve economic efficiency within the safety boundary. Once the coal bed thickness of the faulty medium-speed coal mill stabilizes, increase the output of other coal mills to restore the unit output to normal levels and ensure that the heating load is not reduced. Provided that the superheater temperature does not exceed the design value, the desuperheating water regulating valve is gradually closed, and the burner swing angle is finely adjusted to raise the main steam temperature to within ±2℃ of the design value, thereby reducing the power generation efficiency loss caused by low steam temperature.

8. A system for continuous mill operation under dynamic separator failure in a medium-speed coal mill, employing the method described in any one of claims 1-7, characterized in that... include: The data acquisition and judgment module is used to acquire relevant parameters of the dynamic separator in the medium-speed coal mill and judge whether the dynamic separator has malfunctioned based on the relevant parameters. If a fault is determined to have occurred, a coordinated adjustment is performed on the medium-speed coal mill that sent the fault and its associated systems. The coordinated adjustment includes an initial fault control phase and a stable period optimization phase. The fault adjustment module is used in the initial fault control phase, including controlling the parameters of the faulty medium-speed coal mill, the burner swing angle, the superheater desuperheating water device, and the turbine inlet steam regulating valve. The fault secondary adjustment module is used to adjust the output of the coal mill during the stabilization period optimization phase, including after the dynamic separator reaches a stable state.

9. An electronic device, characterized in that, include: A memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions, which, when executed by the processor, implement the steps of the method for continuous milling under fault conditions of dynamic separator of medium-speed coal mill as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, It stores computer-executable instructions, which, when executed by a processor, implement the steps of the method for continuous milling under fault conditions of the dynamic separator of a medium-speed coal mill as described in any one of claims 1 to 7.

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