[0020] The present invention will be further described in detail below with reference to the drawings and specific embodiments:
[0021] An automatic coal thinning device used in the raw coal transportation system of a thermal power plant. The schematic diagram of the structure is as follows figure 1 Shown. It includes an air supply system 3, a control system 4, and several air injection ports 2. The air injection ports 2 are respectively installed on the inner walls of the equipment of the raw coal transportation system 1. The air injection ports 2 are connected to the air supply system 3 through an air pipe 5. The air supply system 3 Change the working status under the control of the control system 4.
[0022] The raw coal conveying system described in this embodiment includes a raw coal hopper 11, a reducing pipe 12, a gate valve 13, a coal falling pipe 14, a coal feeder 15, and a conveying belt 16, which are arranged from top to bottom in accordance with the conveying direction of the raw coal. There are five in total. The coal falling pipe 14 is provided with a first air injection port, the reducing pipe 12 is provided with a second air injection port, and the raw coal hopper 11 is sequentially provided with a third air injection port, a fourth air injection port and a fifth air injection port from bottom to top.
[0023] The air supply system 3 includes an air compressor 31, an air storage tank 32, a valve 33 and a heater 34. The number of valves 33 is the same as the number of gas injection ports 2, which are respectively arranged on the pipe connecting the gas injection ports; the heater 34 is installed in the gas storage tank, and the controlled end of the heater 34 is connected to the control system 4, under the instruction of the control system Startup or shutdown, it is used to heat the compressed air in the air storage tank in winter. The input end of the air compressor 31 is connected to the compressed air system of the thermal power plant through a pipeline, the output end of the air compressor 31 is connected to an air storage tank 32 through the pipeline, and the output end of the air storage tank 32 is connected to each jet port through the air pipe 5 respectively. 2 Connected.
[0024] The control system 4 includes a control cabinet 41, a coal-break signal acquisition device 42 and a number of solenoid valves 43. The number of the solenoid valves 43 is the same as the number of the jet ports 2, which are respectively arranged on the pipeline connecting the jet ports; the coal-break signal acquisition device 42 It is arranged below the coal feeder and above the conveyor belt in the raw coal conveying system 1 for collecting the amount of coal. The input end of the control cabinet is connected to the output end of the coal cut signal acquisition device 42, and the output end of the control cabinet is respectively connected to the heater and the controlled end of each solenoid valve 43.
[0025] The coal-break signal acquisition device 42 may be a combination of the baffle 421 and the sensor 422, or may be a separately provided weighing sensor assembly 423.
[0026] If the combination of the baffle 421 and the sensor 422 is adopted, the baffle 421 is hinged on the coal feeder's lower coal port frame through a pin shaft, and the baffle is deflected toward the raw coal conveying direction under the action of the raw coal on the conveyor belt; The device 422 is also arranged on the frame of the lower coal port of the coal feeder, and is triggered by the swing amplitude of the baffle; the output end of the sensor is connected to the input end of the control cabinet; the swing amplitude of the baffle is determined according to the coal conveyance. With this kind of structure of the coal-cut signal acquisition device, during the operation, when the amount of raw coal normally conveyed by the conveyor belt is normal, the baffle is inclined at a certain angle, at this time the baffle will trigger the sensor, and the control cabinet will receive the sensor When in the triggered state, the solenoid valve is not activated and the air pipe is cut off; when the amount of raw coal decreases, it means that the raw coal conveying system is blocked. At this time, the inclination angle of the baffle becomes small, and the sensor cannot be triggered, and the controller cannot receive the sensor The returned signal starts to actuate the solenoid valve, the air pipe opens, and the jet port blows air into the raw coal conveying system to achieve the effect of blowing away the raw coal.
[0027] If the coal-break signal acquisition device 42 uses the weighing sensor assembly 423 alone, the weighing sensor assembly 423 is arranged below the conveyor belt to measure the amount of raw coal conveyed on the conveyor belt. When the amount of raw coal is lower than the standard value When the load cell 423 sends a signal to the control cabinet, the control cabinet controls the solenoid valve to act after receiving the signal, the air pipe opens, and the air injection port blows air into the raw coal transportation system to achieve the effect of blowing off the raw coal.
[0028] Of course, the two types of coal cut signal acquisition devices 42 described in the present invention can be installed in the raw coal transportation system at the same time to ensure that the amount of raw coal falling from the coal feeder can be accurately detected.
[0029] The working process of this embodiment is as follows:
[0030] Open the gate valve 13 of the coal feeder's coal inlet, and transport materials to the coal feeder, coal mill and subsequent equipment in turn.
[0031] When the raw coal falls normally and there is no blockage, the transportation direction of the raw coal is as follows figure 1 As shown by the direction of the middle arrow, the raw coal in the coal bunker enters the raw coal hopper, passes through the reducing pipe 12, the gate valve 13 at the inlet of the coal feeder, and the coal feeder 14 at the inlet of the coal feeder, and then is sent to the coal feeder 15. After the coal machine falls into the conveyor belt 16 below the coal feeder, the material is fed to the coal mill.
[0032] When the raw coal is blocked in the conveying system, the coal cut signal acquisition device collects that the amount of raw coal sent to the conveyor belt cannot meet the requirements, causing the belt to break coal, and the coal cut signal acquisition device sends a "belt broken coal" alarm signal to the control cabinet , And start the solenoid valve on each air pipe at the same time.
[0033] In the process of the control cabinet controlling the action of the solenoid valve, the working mode is adopted in which the air injection port is opened alternately in the opposite direction of the raw coal transportation. That is, firstly, open the solenoid valve on the first air pipe connected with the first air jet in the coal drop pipe, so that the first air jet sprays airflow to the coal drop pipe, and the compressed air enters the working surface of the coal drop pipe for coal seam When the preset time is reached, the control cabinet closes the solenoid valve on the first air pipe, and at the same time opens the solenoid valve on the second air pipe connected to the second air nozzle in the reducer to make the second air jet The mouth sprays airflow to the reducing pipe, and the compressed air enters the working surface of the reducing pipe to dredge the coal seam; and so on, then close the second air injection port and open the third air injection port, close the third air injection port, open the fourth air injection port, and close The fourth air jet opens the fifth air jet until the preset dredging time of the fifth air jet arrives, and the first round of dredging passes ends, thereby realizing the timing control of dredging in turn against the raw coal conveying direction.
[0034] After the completion of a high-pressure air flow dredging process, if the coal cut signal still exists, the control cabinet controls the solenoid valve to operate and performs the second round of dredging until the raw coal can be transported normally.
[0035] If the present invention is used in winter, the raw coal is likely to freeze during the transportation of raw coal due to its high humidity. Therefore, it is necessary to freeze or dry the frozen coal during the transportation of raw coal. At this time, control The cabinet can control the heater located in the gas storage tank to enter the working state, and automatically heat the compressed air according to the temperature value set in the control cabinet, so that the compressed air freezes and dries the raw coal during the coal thinning process.
[0036] When the present invention can also realize the operating state of the air supply system by manual control, at this time, when the solenoid valves are all open, manually controlling the valves on the air pipes can realize manual coal thinning.
