Coal flow control method for raw coal transportation system in open-pit coal preparation plant

Abstract

The present invention relates to the technical field of raw coal transportation, and specifically to a method for controlling the flow of coal in a raw coal transportation system of an open-pit coal preparation plant, comprising the following operating steps: detecting whether all equipment in the raw coal transportation system has stopped, whether all equipment has no alarm faults, and whether all equipment is unloaded; calculating the start-up time of each equipment according to the detection result, and making each equipment start in sequence according to the corresponding start-up time, and starting a post-processing task; after completing the task, the raw coal transportation system detects the operating status of each equipment; if the equipment is operating normally, the feeding equipment is controlled to stop running, and detects whether other equipment is in an unloaded state; if other equipment is in a non-unloaded state, the equipment continues to run until it reaches an unloaded state; if other equipment is all in an unloaded state, the raw coal transportation system controls other equipment to stop running; the present invention can preemptively control the start and stop status of each equipment in the raw coal transportation system, thereby ensuring smooth and safe operation of the system.

Description

Technical Field

[0001] The present invention relates to the technical field of raw coal transportation, in particular to a method for controlling coal flow in a raw coal transportation system of an open-pit coal preparation plant. Background Art

[0002] Open-pit coal preparation plants are characterized by high production volumes, intermittent material feeding, and long distances between the mining area and the raw coal bunker. The raw coal transportation system in open-pit coal preparation plants primarily consists of several high-power, ultra-long-distance variable-frequency driven belt conveyors. Each high-power, ultra-long-distance belt conveyor requires numerous protective devices and auxiliary equipment. Protective devices typically include rope pull protection, stall protection, smoke protection, coal pile protection, over-temperature protection, and deviation protection. Auxiliary equipment typically includes oil pump systems, fan systems, brake systems, and cooling systems. This complex system complicates the raw coal transportation system in open-pit coal preparation plants, increasing power load and energy consumption. During operation, the raw coal transportation system typically performs a delayed start-up of each device in the system, one at a time, counter to the coal flow. This start-up method not only results in excessive equipment idling time but also increases equipment wear, hindering energy conservation and consumption reduction. Furthermore, due to intermittent material feeding, the amount of material on the belt conveyor fluctuates. If the belt conveyor operates at maximum speed without adjusting the speed according to the material flow, this is also detrimental to energy conservation and emission reduction, thus urgently requiring a solution. Summary of the Invention

[0003] To avoid and overcome the technical problems existing in the prior art, the present invention provides a method for controlling the flow of coal in a raw coal transportation system in an open-pit coal preparation plant. The present invention can precisely control the start and stop conditions of various devices in the raw coal transportation system, thereby ensuring smooth and safe operation of the system.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] The method for controlling the flow of raw coal in the open-pit coal preparation plant's raw coal transportation system includes the following steps:

[0006] S1. Check whether all equipment in the raw coal transportation system has stopped, whether there are no alarm faults, and whether all equipment is unloaded. If all equipment has stopped, no alarm faults, and no load, the raw coal transportation system sends a coal flow intelligent centralized control start signal to each equipment; otherwise, the raw coal transportation system stops operation.

[0007] S2. Calculate the startup time of each device and start each device in sequence according to the corresponding startup time. If any device encounters an abnormality during the startup process, the current device and all devices that were running before the current device are stopped, and the raw coal transportation system is shut down. Otherwise, the raw coal transportation system starts normally according to the startup time and starts the post-processing task.

[0008] S3. After completing the task, the raw coal transportation system detects the operating status of each device; if the equipment is operating normally, the feeding equipment is controlled to stop running, and the other equipment is detected to see if they are in a no-load state; if other equipment is not in a no-load state, the equipment continues to run until it reaches a no-load state; if all other equipment are in a no-load state, the raw coal transportation system controls the other equipment to stop running.

[0009] As a further solution of the present invention: the specific content of step S1 is as follows:

[0010] S11. If all equipment in the raw coal transportation system has no protective devices in operation, no fault alarms, and is in a stopped and no-load state, the raw coal transportation system enters the coal-flow intelligent centralized control start mode; the intelligent start flag is set, and the raw coal transportation system in the coal-flow intelligent centralized control start mode sends a coal-flow centralized control start signal to each equipment; while the raw coal transportation system sends the coal-flow centralized control start signal, the interlocking relationship between each equipment is released, i.e., unlocked;

[0011] If the equipment in the raw coal transportation system has a protective device activated or a fault alarm is issued, or is in operation or in a non-no-load state, the raw coal transportation system will not enter the coal flow intelligent centralized control start mode, and the intelligent start flag cannot be set. The raw coal transportation system cannot send a coal flow centralized control start signal, and the raw coal transportation system will exit operation;

[0012] S12. After the raw coal transportation system sends out a coal flow centralized control start signal and each device receives the coal flow centralized control start signal, the raw coal transportation system switches from the coal flow intelligent centralized control start mode to the centralized control mode.

[0013] As a further solution of the present invention: the specific steps of step S2 are as follows:

[0014] S21. Calculate the startup time of the current device. The startup time t of the current device is calculated using the following formula:

[0015]

[0016] Among them, L is the distance that the material runs from the feed port of the upper level equipment of the current equipment to the discharge port; L1 is the distance that the material runs from the safety point of the upper level equipment of the current equipment to the discharge port; v is the operating speed of the upper level equipment of the current equipment, P i is the operating power of the current device; P i-1 The operating power of the device above the current device;

[0017] S22. After the start-up time of each device is calculated, the feeding device is turned on first. When the material enters the feeding device, the next-level device starts to start. After the start-up time, the next-level device is fully started. When the next-level device is fully started, the material runs a distance L1 on the feeding device and falls onto the next-level device. At the same time, the next-level device of the next-level device starts to start. After the start-up time, the next-level device of the next-level device is fully started. And so on, each device is fully started in sequence along the direction of coal flow.

[0018] As a further solution of the present invention: during the equipment startup process, after the material falls into the upper-level equipment, if the current equipment fails to start normally within the startup time or stops abnormally after startup, it is necessary to stop the current equipment and all equipment in the direction of the material coming from the current equipment at the same time, and the raw coal transportation system exits the coal flow intelligent centralized control startup program and cancels the coal flow centralized control startup signal.

[0019] As a further solution of the present invention: if the startup time of a device in the raw coal transportation system is more than twice the startup time t in step S21, the startup time is defined as the extended time T. The calculation formula of the extended time T is as follows:

[0020] T=t 油 +t 风 +t 冷 +t 制 +t 上 +t 中

[0021]

[0022]

[0023] Among them, t 上 Indicates the startup time of the current device in the upper-level device; t 中 It represents the sum of the time that materials run in all equipment before the previous equipment of the current equipment along the direction of coal flow; t 油 Indicates the startup time of the oil pump system of the current equipment; t 风 Indicates the startup time of the fan system of the current device; t 冷 Indicates the startup time of the current equipment cooling system; t 制 Indicates the start time of the braking system of the current equipment; n indicates the number of equipment located before the previous equipment of the current equipment along the coal flow direction; L i v represents the distance from the feed port to the discharge port of the i-th device among n devices; i Indicates the operating speed of the i-th device among n devices; L 上 Indicates the distance from the feed port to the discharge port of the previous level device of the current device; L1,上 Indicates the distance from the safety point to the discharge port in the upper level equipment of the current equipment; P 本 Indicates the current operating power of the device; P 上 Indicates the operating power of the device above the current device; v 上 Indicates the operating speed of the device above the current device;

[0024] After calculating the extended time T, take the current equipment as the base point and move forward in the reverse direction of coal flow, and 油 , t 风 , t 冷 and t 制 The sum is taken as the start-up time of the current equipment before the material enters the feeding equipment.

[0025] As a further solution of the present invention: in the start-up mode of the Shunmei intelligent centralized control, a camera for image recognition of coal quantity is installed at the safety point of the upper-level equipment. When the camera recognizes the coal flow, the current equipment has been fully started;

[0026] If the current equipment fails to start completely within the startup time t or when the camera recognizes the coal flow, the materials transported by the previous equipment will not be transferred to the current equipment;

[0027] In the coal-flow intelligent centralized control startup mode, if the next-level equipment of the feeding equipment and the remaining equipment in the raw coal transportation system are started and then stop running due to abnormal conditions, it is necessary to stop all equipment in the direction of the current equipment at the same time, exit the coal-flow intelligent centralized control startup mode, and cancel the coal-flow centralized control startup signal;

[0028] In the coal flow intelligent centralized control start-up mode, when the equipment starts and runs normally, the equipment's no-load signal is reset; when all equipment in the raw coal transportation system has started and is running normally, the raw coal transportation system's coal flow start-up is completed and the locking relationship is automatically opened. At the same time, the coal flow centralized control start-up signal is eliminated and the intelligent start-up flag is reset.

[0029] As a further solution of the present invention: the specific content of step S3 is as follows:

[0030] S31. After no more materials are fed into the feeding equipment, that is, after all materials in the current task are transported, if all equipment in the raw coal transportation system is operating normally, the raw coal transportation system enters the coal flow intelligent centralized control stop mode, and the intelligent stop sign is set; the raw coal transportation system in the coal flow intelligent centralized control stop mode sends a coal flow centralized control stop signal to each equipment;

[0031] After receiving the stop signal from the coal flow centralized control, the feeding equipment at the source of the raw coal transportation system stops running and stops feeding;

[0032] If there is equipment in the raw coal transportation system that is operating normally, the raw coal transportation system will not enter the coal flow intelligent centralized control stop mode, and the intelligent stop sign cannot be set. The raw coal transportation system cannot issue a coal flow centralized control stop signal, and the raw coal transportation system will exit operation;

[0033] S32. After the feeding equipment stops running, the next level equipment of the feeding equipment is in the coal flow intelligent centralized control stop mode and the next level equipment receives the coal flow centralized control stop signal and the feeding equipment stop signal. If the timing mode is adopted, the raw coal transportation system starts synchronous timing. When the timing time reaches the stop time, the raw coal transportation system determines that the next level equipment is empty and sets the empty signal bit of the next level equipment. The stop time is mainly determined by the time required for all materials on the current equipment to be transferred to the next level equipment. The stop time t 停 The calculation formula is as follows:

[0034]

[0035] If the image recognition mode is used, a camera that detects the amount of coal through image recognition is installed at the discharge port of the current equipment. When the camera's image recognition shows that there is no material, the raw coal transportation system determines that the current equipment is empty and sets the empty signal bit of the current equipment;

[0036] When the current equipment is in the stop mode of the coal flow intelligent centralized control and receives the stop signal of the coal flow centralized control and the feeding equipment stop signal, and the current equipment no-load signal is set, the raw coal transportation system stops the current equipment operation;

[0037] When all equipment in the raw coal transportation system have set the no-load signal and completed the coal flow centralized control parking, the intelligent parking flag is reset, the coal flow centralized control parking signal issued by the raw coal transportation system is canceled, and the raw coal transportation system coal flow intelligent centralized control parking is completed.

[0038] As a further solution of the present invention: the operating frequency of each device of the raw coal transportation system in the intelligent start mode and the intelligent stop mode along the coal flow is 50 Hz.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] 1. The belt conveyor of the present invention automatically adjusts the current running speed of the belt conveyor according to the current instantaneous coal flow rate and the total coal amount, so as to achieve the matching between the material amount of the belt conveyor and the running speed of the belt conveyor, reduce power consumption, and achieve energy saving and consumption reduction.

[0041] In summary, the start-stop and belt speed control method and equipment of the raw coal transportation system in the open-pit coal preparation plant can greatly shorten the unnecessary idling time and idling wear during the start-up and stop process, as well as the automatic adjustment of the belt speed, reduce the consumption of electricity, and achieve energy conservation and emission reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is the main control flow chart of the present invention.

[0043] Figure 2 This is a schematic diagram of the coal flow startup process in the present invention.

[0044] Figure 3 It is a schematic diagram of the coal flow stopping process in the present invention.

[0045] Figure 4 This is a flow chart of an example of a raw coal transportation system according to the present invention. DETAILED DESCRIPTION

[0046] The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0047] See also Figures 1 to 3 In the embodiment of the present invention, each device in the raw coal transportation system adopts a high-power ultra-long-distance belt conveyor, and the transportation of raw coal is achieved through the cooperation between each high-power ultra-long-distance belt conveyor.

[0048] The belt length of each high-power ultra-long belt conveyor is more than 1 kilometer, and a corresponding PLC workstation is separately configured. The various protection device signals of each device, the control of auxiliary equipment and the operation of the main equipment are all completed by this PLC workstation to complete the signal acquisition, control and operation. Network data communication is established between the PLC workstations of each device in the raw coal transportation system. According to the type of PLC used and the supported communication methods, such as Ethernet Modbus TCP, fieldbus ModbusRTU, EntherNet / IP, etc., a raw coal transportation system communication network is established to realize data transmission and information sharing of each independent device PLC workstation. Since the PLC workstations of each device are independent, data transmission and information sharing are realized by building a raw coal transportation system communication network, but the status of the PLC workstations of each device is equal.

[0049] In order to coordinate and control the start and stop of the raw coal transportation system along the coal flow in a unified manner, it is necessary to select a PLC workstation of a device in the raw coal transportation system as the control center for the start and stop of the raw coal transportation system along the coal flow, and gather the protection devices, fault alarms, operating status and other signals of each device in the raw coal transportation system to the control center PLC workstation through network communication, and transmit the various operation signals of the start and stop control along the coal flow to the PLC workstations of each device in the raw coal transportation system through network communication.

[0050] Setting the start mode of intelligent centralized control along the coal flow indicates that the raw coal transportation system starts according to the centralized control along the coal flow; using intelligent start, intelligent stop, cancellation of intelligent start and cancellation of intelligent stop signs as the start signal, stop signal, cancellation of intelligent along the coal flow start signal and cancellation of intelligent along the coal flow stop signal of the raw coal transportation system along the coal flow centralized control.

[0051] like Figure 2 As shown in the coal flow startup flow chart, the intelligent centralized control startup of coal flow includes obtaining the status of each equipment in the raw coal transportation system and checking whether all equipment are stopped and all are unloaded.

[0052] If all equipment in the raw coal transportation system has no protective devices in operation, no fault alarms, is in a stopped state, no-load, and is in the coal flow intelligent centralized control start mode, the intelligent start flag is set and the raw coal transportation system sends a coal flow centralized control start signal; if a device in the raw coal transportation system has a protective device in operation or a fault alarm or is not no-loaded or in a running state, the intelligent start flag cannot be set and the system cannot send a coal flow centralized control start signal.

[0053] After the system sends the coal flow centralized control start signal, it automatically switches all equipment in the raw coal transportation system to centralized control mode, and releases the locking relationship between each equipment during the period when the system sends the coal flow centralized control start signal, that is, unlocks.

[0054] If variable frequency driven equipment is used in the raw coal transportation system, when the system sends a start signal for the coal flow centralized control, the frequency conversion frequency of the corresponding equipment will be automatically set to 50Hz, that is, it will run at the maximum speed during the start-up period of the coal flow, avoiding the occurrence of coal pile accidents and ensuring safe and reliable production.

[0055] If there are high-power variable frequency multi-drive long-distance belt conveyors and other equipment with long startup time in the raw coal transportation system, due to the large number of auxiliary system equipment, including oil pump system, fan system, brake system, cooling system, and complex process, in order to reduce the impact of the starting current of high-power equipment on the power grid, the frequency conversion acceleration time of the equipment is increased, the time of its startup process is prolonged, and the startup is slow. When starting along the coal flow, the upper-level equipment of the equipment has been started and is running with load, that is, transporting coal. However, the current equipment has not yet completed the startup, resulting in all the coal transported by the previous equipment being piled up on the current equipment, causing coal pile accidents. In order to avoid coal pile accidents caused by the slow startup of the current equipment, after the coal flow centralized control startup signal is issued, the equipment with a longer startup time is used as the first startup equipment. After the equipment has been started for a period of time T, the first equipment along the coal flow direction, that is, the feeding equipment, can be started; the extension time T is mainly based on the time t required for the current equipment to be fully started. 本 The time t required for the material to be transported from the intermediate equipment to the current equipment after the feeding equipment is started 中 The sum is determined, where t 本 Start time of oil pump system t 油 , Fan system start time t 风 , Cooling system start-up time t 冷 and the braking system activation time t 制 The sum of 中 Determined by the transit time of several belt conveyors, assuming that the length of the belt of one belt conveyor is L i , the maximum operating frequency f is 50Hz, the unit is meter per second, when the operating frequency is f, the operating speed is v i , then the transit time t of the i-th intermediate device 中i for:

[0056]

[0057] The extended time T is:

[0058] T=t 油 +t 风 +t 冷 +t 制 +t 上 +t 中

[0059]

[0060]

[0061] Assume that the current equipment takes 100 seconds to fully start up, and after the feeding equipment is started, it takes 60 seconds for the material to be transported to the current equipment through the intermediate equipment. The startup time in the equipment above the current equipment is 5 seconds. Then, the feeding equipment can be started 35 seconds after the current equipment is started. It takes 65 seconds for the feeding equipment to transport the material to the current equipment. It takes exactly 100 seconds for the material to be transported through the feeding equipment and the intermediate equipment to the current equipment. The current equipment is fully started and can directly transport the material. If there is no equipment with a long startup time in the raw coal transportation system, the feeding equipment can be started directly. Generally, to avoid coal pile accidents and for safety reasons, the feeding equipment and the equipment below the feeding equipment are started at the same time. Because the feeding equipment is generally a coal feeder or a feeding scraper, it is generally started directly and the material is directly transferred to the next equipment after startup. If the next equipment is not started at this time, it will cause coal pile accidents.

[0062] After the previous level equipment of the current equipment is started, if the current equipment fails to start normally within the start time t or stops abnormally after starting, the locking relationship between the upstream and downstream equipment is released during the start of the intelligent centralized control of the coal flow, that is, unlocked; therefore, it is necessary to urgently stop all equipment in the direction of the material coming from the equipment at the same time, that is, all equipment between the equipment and the feeding equipment must be urgently stopped at the same time, and the start program of the intelligent centralized control of the coal flow must be exited, and the start signal of the intelligent centralized control of the coal flow must be canceled. For safety reasons, to avoid the occurrence of coal stacking accidents, the corresponding safety time is calculated based on the belt speed of the previous level equipment belt conveyor and the safe distance between the material being transported on the belt conveyor and the tail discharge port; assuming that the distance from the tail to the head of the belt conveyor is L, the safety distance is L1, and the operating speed is v, the start time t is:

[0063]

[0064] In the coal flow start-up mode, if a camera for coal quantity image recognition is installed at a distance from the head of the belt conveyor of the upper-level equipment, the start-up conditions of the current equipment are: In the coal flow intelligent centralized control start-up mode, a camera for coal quantity image recognition is installed at the safety point of the upper-level equipment. When the camera recognizes the coal flow, the current equipment has been fully started.

[0065] In this way, if the current equipment fails to start successfully within the startup time t or before the image recognizes the coal flow, the materials transported by the upper-level equipment will not be transferred to the current equipment, thereby avoiding the occurrence of coal stacking accidents and improving the reliability of the intelligent centralized control system for coal flow.

[0066] In the coal-flow intelligent centralized control startup mode, if the next-level equipment of the feeding equipment and the remaining equipment in the raw coal transportation system are started and then stop running due to abnormal conditions, it is necessary to stop all equipment in the direction of the current equipment at the same time, exit the coal-flow intelligent centralized control startup mode, and cancel the coal-flow centralized control startup signal;

[0067] In the coal flow intelligent centralized control start-up mode, when the equipment starts and runs normally, the equipment's no-load signal is reset; when all equipment in the raw coal transportation system has started and is running normally, the raw coal transportation system's coal flow start-up is completed and the locking relationship is automatically opened. At the same time, the coal flow centralized control start-up signal is eliminated and the intelligent start-up flag is reset.

[0068] like Figure 3 As shown in the flow chart of coal flow stop, the intelligent centralized control stop of coal flow includes obtaining the operating status of each equipment in the raw coal transportation system and judging whether it is empty.

[0069] After no more materials are fed into the feeding equipment, that is, after all materials in the current task are transported, if all equipment in the raw coal transportation system operates normally, the raw coal transportation system enters the coal flow intelligent centralized control stop mode, and the intelligent parking sign is set; the raw coal transportation system in the coal flow intelligent centralized control stop mode sends a coal flow centralized control stop signal to each equipment.

[0070] After the feeding equipment at the source of the raw coal transportation system receives the stop signal from the coal flow centralized control, the feeding equipment stops running and stops feeding.

[0071] If there is equipment in the raw coal transportation system that is operating normally, the raw coal transportation system will not enter the coal flow intelligent centralized control stop mode, and the intelligent stop sign cannot be set. The raw coal transportation system cannot send a coal flow centralized control stop signal, and the raw coal transportation system will exit operation.

[0072] After the feeding equipment stops running, the next level equipment of the feeding equipment is in the coal flow intelligent centralized control stop mode and the next level equipment receives the coal flow centralized control stop signal and the feeding equipment stop signal. If the timing mode is adopted, the raw coal transportation system starts synchronous timing. When the timing time reaches the stop time, the raw coal transportation system determines that the next level equipment is empty and sets the empty signal bit of the next level equipment. The stop time is mainly determined by the time required for all materials on the current equipment to be transferred to the next level equipment. The stop time t 停 The calculation formula is as follows:

[0073]

[0074] If the image recognition mode is used, a camera that detects the amount of coal through image recognition is installed at the discharge port of the current equipment. When the camera's image recognition shows that there is no material, the raw coal transportation system determines that the current equipment is empty and sets the empty signal bit of the current equipment;

[0075] If the current equipment is in the coal flow intelligent centralized control stop mode and receives a coal flow centralized control stop signal and a feeding equipment stop signal, and the current equipment's no-load signal is set, the raw coal transportation system stops the current equipment. When all equipment in the raw coal transportation system has set its no-load signal and completed the coal flow centralized control stop, the intelligent stop flag is reset, canceling the coal flow centralized control stop signal issued by the raw coal transportation system, and completing the coal flow intelligent centralized control stop of the raw coal transportation system.

[0076] The belt conveyor in the raw coal transportation system is equipped with a camera at the tail of the machine, close to the discharge port of the upper equipment, and a safe distance L from the head of the belt conveyor. 安 A camera is installed at the position for image recognition monitoring of the presence and amount of material on the belt conveyor; the safety distance L 安 It is mainly based on the distance required for the next level of equipment to start up when the material is transported to the position of the machine head camera by the current belt conveyor, and the distance required for the next level of equipment to be fully started when the material is transported to the discharge port of the machine head by the current belt conveyor and falls to the next level of equipment.

[0077] like Figure 4 As shown, taking the raw coal transportation system of an open-pit coal preparation plant as an example, the start-up time of the 401 feeder is 20 seconds, the start-up time of the 402 belt conveyor is 30 seconds + the start-up time of auxiliary equipment is 60, the start-up time of the 403B belt conveyor is 120 seconds + the start-up time of auxiliary equipment is 240 seconds, the start-up time of the 403A belt conveyor is 65 seconds + the start-up time of auxiliary equipment is 70 seconds, the start-up time of the 405 / 406 crusher is 30 seconds, the start-up time of the A102 belt conveyor is 45 seconds + the start-up time of auxiliary equipment is 60 seconds, and the start-up time of the 201A, 201B, and 201C belt conveyors is 30 seconds each. The total start-up time is 770 seconds before material transportation can begin; when the intelligent centralized control of the coal flow is used to start the vehicle, it only takes 250 seconds to start material transportation, and there is no equipment idling. The time to start material transportation is advanced by 520 seconds, which greatly saves the time of the startup process, reduces energy consumption and equipment idling wear.

[0078] The feeding of the raw coal transportation system of the open-pit coal preparation plant is that the mine car transports the coal in the mining area to the feeding equipment at the pit entrance. After the material is transferred to the raw coal transportation system through the feeding equipment, the mine car transports the material to the feeding equipment discontinuously and intermittently, which will cause the belt conveyor in the raw coal transportation system to have varying transport volumes, and sometimes even no-load conditions. Since the raw coal transportation system of the open-pit coal preparation plant adopts a high-power variable-frequency multi-drive ultra-long belt conveyor, if the belt conveyor has a small transport volume or is no-loaded, and the belt conveyor still maintains full speed or high-speed operation, a large amount of electricity will be wasted, as well as equipment losses, which is not conducive to energy conservation and consumption reduction. The coal volume of the belt conveyor is dynamically and real-timely monitored online based on the cameras installed at the tail and near the head of the belt conveyor. The instantaneous coal flow of the current belt conveyor is monitored in real time through image recognition technology, and the instantaneous coal flow after identification is intelligently calculated to calculate the total amount of coal on the current belt conveyor in real time.

[0079] The current running speed of the belt conveyor is automatically adjusted based on the current instantaneous coal flow rate of the belt conveyor, the total amount of coal on the belt conveyor and the current running current of the belt conveyor. The speed control strategy of the belt conveyor is shown in Table 1 below.

[0080] Table 1 Speed ​​control strategy of belt conveyor

[0081]

[0082] The belt conveyor automatically adjusts the current operating speed of the belt conveyor according to the current instantaneous coal flow and total coal volume, so as to achieve the matching of the belt conveyor's material volume and the belt conveyor's operating speed, reduce power consumption, and achieve energy saving and consumption reduction.

[0083] In summary, the start-stop and belt speed control methods and equipment for the raw coal transportation system of an open-pit coal preparation plant can significantly shorten unnecessary idling time and idling wear during the start-up and stop process, as well as automatically adjust the belt speed, reduce electricity consumption, and achieve energy conservation and emission reduction.

[0084] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A method for controlling the flow of raw coal in a raw coal transportation system of an open-pit coal preparation plant, characterized in that: The following steps are included: S1. Check whether all equipment in the raw coal transportation system has stopped, whether there are no alarm faults, and whether all equipment is unloaded. If all equipment has stopped, no alarm faults, and no load, the raw coal transportation system sends a coal flow intelligent centralized control start signal to each equipment; otherwise, the raw coal transportation system stops operation. S2. Calculate the startup time of each device and start each device in sequence according to the corresponding startup time; If, during the startup process, an equipment encounters an abnormality at the corresponding startup time, the current equipment and all equipment that ran before the current equipment will be stopped, and the raw coal transportation system will exit operation; otherwise, the raw coal transportation system will start normally according to the startup time and start the post-processing task; S3. After completing the task, the raw coal transportation system checks the operating status of each device; if the device is operating normally, the feeding device is controlled to stop running, and the other devices are checked to see if they are in an unloaded state; if other devices are not in an unloaded state, the device continues to run until it reaches an unloaded state; if other devices are all in an unloaded state, the raw coal transportation system controls the other devices to stop running; The specific content of step S1 is as follows: S11. If all equipment in the raw coal transportation system has no protective devices in operation, no fault alarms, and is in a stopped and no-load state, the raw coal transportation system enters the coal-flow intelligent centralized control start mode; the intelligent start flag is set, and the raw coal transportation system in the coal-flow intelligent centralized control start mode sends a coal-flow centralized control start signal to each equipment; while the raw coal transportation system sends the coal-flow centralized control start signal, the interlocking relationship between each equipment is released, i.e., unlocked; If the equipment in the raw coal transportation system has a protective device activated or a fault alarm is issued, or is in operation or in a non-no-load state, the raw coal transportation system will not enter the coal flow intelligent centralized control start mode, and the intelligent start flag cannot be set. The raw coal transportation system cannot send a coal flow centralized control start signal, and the raw coal transportation system will exit operation; S12: After the raw coal transportation system sends a coal flow centralized control start signal and each device receives the coal flow centralized control start signal, the raw coal transportation system switches from the coal flow intelligent centralized control start mode to the centralized control mode; The specific steps of step S2 are as follows: S21. Calculate the startup time of the current device. t The calculation is done using the following formula: in, L The distance the material runs from the feed port to the discharge port of the upper level equipment of the current equipment; L 1 is the distance the material travels from the safety point of the upper level equipment of the current equipment to the discharge port; v It is the operating speed of the upper level device of the current device. P i is the current operating power of the device; P i-1 The operating power of the device above the current device; S22, after calculating the start-up time of each device, first start the feeding device, when the material enters the feeding device, the next level device starts to start, after the start-up time, the next level device is fully started; when the material is fully started on the feeding device, the material runs for a distance L 1, it falls to the next level equipment. At the same time, the next level equipment of the next level equipment starts to start. After the start-up time, the next level equipment of the next level equipment is fully started. And so on, each equipment is fully started in sequence along the direction of coal flow. During the equipment startup process, after the material falls to the upper level equipment, if the current equipment fails to start normally within the startup time or stops abnormally after starting, it is necessary to stop the current equipment and all equipment in the direction of the current equipment at the same time, and the raw coal transportation system exits the coal flow intelligent centralized control startup program and cancels the coal flow centralized control startup signal. If the startup time of the equipment in the raw coal transportation system is more than twice the startup time t in step S21, the startup time is defined as the extended time. T , extend the time T The calculation formula is as follows: in, t 上 Indicates the startup time of the current device in the upper-level device; t 中 It indicates the sum of the time that materials run in all equipment before the previous equipment of the current equipment along the coal flow direction; t 油 Indicates the start time of the oil pump system of the current equipment; t 风 Indicates the startup time of the fan system of the current device; t 冷 Indicates the startup time of the current equipment cooling system; t 制 Indicates the start time of the current equipment braking system; n Indicates the number of devices located before the previous device of the current device along the coal flow direction; L i express n Device i The distance from the feed port to the discharge port of each device; v i express n Device i The operating speed of each device; L 上 Indicates the distance from the feed port to the discharge port of the previous level device of the current device; L 1,上 Indicates the distance from the safety point to the discharge port in the upper level equipment of the current equipment; P 本 Indicates the current operating power of the device; P 上 Indicates the operating power of the device above the current device; v 上 Indicates the operating speed of the device above the current device; When calculating the extended time T After that, take the current equipment as the base point, move forward in the reverse direction of coal flow, and t 油 、 t 风 、 t 冷 and t 制 The sum is taken as the start-up time of the current equipment before the material enters the feeding equipment.

2. The method for controlling the flow of coal in the raw coal transportation system of an open-pit coal preparation plant according to claim 1, characterized in that: In the start-up mode of Shunmei intelligent centralized control, a camera for image recognition of coal quantity is installed at the safety point of the upper-level equipment. When the camera recognizes the coal flow, the current equipment has been fully started; If at startup time t When the coal flow is detected by the camera, if the current equipment fails to start completely, the materials transported by the upper equipment will not be transferred to the current equipment; In the coal-flow intelligent centralized control startup mode, if the next-level equipment of the feeding equipment and the remaining equipment in the raw coal transportation system are started and then stop running due to abnormal conditions, it is necessary to stop all equipment in the direction of the current equipment at the same time, exit the coal-flow intelligent centralized control startup mode, and cancel the coal-flow centralized control startup signal; In the coal flow intelligent centralized control start-up mode, when the equipment starts and runs normally, the equipment's no-load signal is reset; when all equipment in the raw coal transportation system has started and is running normally, the raw coal transportation system's coal flow start-up is completed and the locking relationship is automatically opened. At the same time, the coal flow centralized control start-up signal is eliminated and the intelligent start-up flag is reset.

3. The method for controlling the flow of coal in the raw coal transportation system of an open-pit coal preparation plant according to claim 1 or 2, characterized in that: The specific content of step S3 is as follows: S31. After no more materials are fed into the feeding equipment, that is, after all materials in the current task are transported, if all equipment in the raw coal transportation system is operating normally, the raw coal transportation system enters the coal flow intelligent centralized control stop mode, and the intelligent stop sign is set; the raw coal transportation system in the coal flow intelligent centralized control stop mode sends a coal flow centralized control stop signal to each equipment; After receiving the stop signal from the coal flow centralized control, the feeding equipment at the source of the raw coal transportation system stops running and stops feeding; If there is equipment in the raw coal transportation system that is operating normally, the raw coal transportation system will not enter the coal flow intelligent centralized control stop mode, and the intelligent stop sign cannot be set. The raw coal transportation system cannot issue a coal flow centralized control stop signal, and the raw coal transportation system will exit operation; S32. After the feeding equipment stops running, the next level equipment of the feeding equipment is in the coal flow intelligent centralized control stop mode and the next level equipment receives the coal flow centralized control stop signal and the feeding equipment stop signal. If the timing mode is adopted, the raw coal transportation system starts synchronous timing. When the timing time reaches the stop time, the raw coal transportation system determines that the next level equipment is empty and sets the empty signal bit of the next level equipment. The stop time is mainly determined according to the time required for all materials on the current equipment to be transferred to the next level equipment. The stop time t 停 The calculation formula is as follows: If the image recognition mode is used, a camera that detects the amount of coal through image recognition is installed at the discharge port of the current equipment. When the camera's image recognition shows that there is no material, the raw coal transportation system determines that the current equipment is empty and sets the empty signal bit of the current equipment; When the current equipment is in the stop mode of the coal flow intelligent centralized control and receives the stop signal of the coal flow centralized control and the feeding equipment stop signal, and the current equipment no-load signal is set, the raw coal transportation system stops the current equipment operation; When all equipment in the raw coal transportation system have set the no-load signal and completed the coal flow centralized control parking, the intelligent parking flag is reset, the coal flow centralized control parking signal issued by the raw coal transportation system is canceled, and the raw coal transportation system coal flow intelligent centralized control parking is completed.

4. The method for controlling the flow of coal in the raw coal transportation system of an open-pit coal preparation plant according to claim 3, characterized in that: The operating frequency of each device in the raw coal transportation system in the intelligent start mode and the intelligent stop mode along the coal flow is 50Hz.

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