Dust-free pebbles discharge system

Overview

 

The dust-free pebbles discharge system developed by our company is a sealed pebbles discharge system. It adopts a single-stage pebbles storage and transportation method to make full use of the space between the pulverized coal discharge outlet of the coal mill and the ground to increase the stone. The effective volume of the coal bucket improves the efficiency of the pebble coal discharge; the use of pneumatic pre-pressure sealing increases the sealing of the joint surface of the telescopic head and the pebble coal bucket, so that the pebble coal discharge process is always in a good sealed state, effectively eliminating coal Dust pollution; the use of centralized exhaust filtration system to completely eliminate the pressure relief pollution of the pebble coal bunker; the use of automatic program control, good reliability, greatly improving the working environment of the boiler room, will become one of the main conveying methods of pebble coal conveying system in thermal power plants, the The system can also use other particulate material storage and transfer systems.

 

work process

 

Operating sequence of the operator: press the open button, open the vibrator (if the system is configured), set the vibration time, close the discharge isolation valve, close the discharge isolation valve in place (if the closure is not in place, the system automatically opens and closes the valve three times, and performs the operation after it is in place The next step; if the three-time closing is not in place, the maintenance isolation valve is closed, and at the same time, a sound and light alarm for the discharge isolation valve failure is issued). Open the exhaust valve to maintain the set time, open the sealed telescopic head cylinder, the telescopic head moves upwards, and the control panel issues an audible and visual alarm for the movement of the stone coal bucket after it is moved up.

 

The operator starts the forklift and moves the stone coal bucket out of the discharge position of the coal mill. The forklift truck places the empty stone coal bucket in place. After the stone bucket is in place, the operator presses the reset switch, and the seal telescopic head automatically resets. Open the discharge isolation valve for secondary feeding, one by one or in a cycle, and transfer the coal from the coal mill.

 

Functions of major equipment

 

The main equipment includes: pneumatic maintenance isolation valve, pneumatic discharge isolation valve, vibrator (configured according to user requirements), multi-functional filtering and sealing bin, movable stone coal bucket, stone coal bucket weighing device, pressure relief filter (if configured), etc. composition.

 

Isolation valve for maintenance: The pulverized coal gas discharge of the coal mill is turned off. The discharge isolation valve is used as a shut-off isolation valve when it is faulty or overhauled. It is opened when normal.

 

● Vibrator: It is installed on the blanking tube and actively assists the pebble coal to fall. Optional according to user requirements.

 

● Discharge isolation valve: Isolate the coal mill and the movable stone coal shovel. When the movable stone coal shovel needs to be removed, close the pneumatic discharge isolation valve to isolate the pebble coal falling pipe to prevent leakage of coal powder.

 

● Multi-functional filtering and sealing warehouse: It has the functions of sealing the movable stone coal bucket, filtering and discharging residual pressure, and is a key component of the system. The system adopts the cylinder pre-pressure seal, which increases the reliability of the seal between the stone bucket and the telescopic head of the sealed bin, effectively eliminates the leakage pollution of the sealed bin, and ensures the system's dust-free operation.

 

● Stone coal bucket weighing device: It is used to detect the quality of the stone coal in the stone bucket. After reaching the set value, an audible and visual alarm is issued, and the signal can be sent to DCS or other control systems. The unique design of the system, after each empty bucket reset, the empty weight is automatically measured, and the errors caused by other factors can be corrected each time to achieve the most accurate alarm and improve the reliability of the system operation.

 

● Moving pebbles: Make full use of the space below the pulverizer discharge port of the coal mill, increase the pebbles capacity, and improve the efficiency of pebbles transportation. The stored and transported pebble coal is used in conjunction with a special forklift to transport the pebble coal to a designated place.

 

● Special Forklift: A special forklift equipped with a 360º spinner is used to conveniently discharge the pebble coal from the pebble bucket. Customers configure as many as needed.

 

● Emission filter: Each furnace is equipped with a filter with an exhaust fan. After the discharge isolation valve is closed, first open the filter and the pebbles exhaust valve to discharge the remaining gas in the pebbles and clean them. Discharge, completely solve the problem of pollution caused by the pebbles. Emission filters are optional equipment and are provided according to customer requirements.

 

● Local control panel: using unit control, one set for each stone bucket, automatic control by PLC program, multi-channel interface is reserved, and various control can be realized, including: local control, local centralized control, remote Manual control, etc., greatly facilitate the use of customers.

 

System configuration recommendations

 

Maintenance isolation valve: installation number + 1 spare; installation of drainage isolation valve + 2 spare; vibrator: installation number + 1 spare; multi-functional sealed warehouse: installation number + 1 spare; movable stone coal bucket: installation quantity +2 spares; stone coal bucket weighing device: installed quantity + 2 spares; special forklift: used quantity +1 spare; control panel: installed quantity +1 spare and so on.

 

System Features ● The system design concept is adopted, the equipment configuration is more reasonable, and the control process is more reliable, which can completely solve the problem of pebble coal pollution.

 

● Full-channel unobstructed structure valve is adopted to ensure reliable valve operation.

 

● The discharge isolation valve is closed and controlled automatically, which greatly increases the reliability of the discharge isolation valve.

 

● Weighing system adopts each empty weight to weigh and record, eliminating errors that may be caused by other factors, ensuring the reliability of the weighing system, and avoiding the occurrence of measurement false alarms.

 

● Automatic pressure relief and dust filtration, reducing the workload of workers, effectively preventing pressure relief pollution, and ensuring that there is no dust leakage during the system working process.

 

● The special structure of the sealed telescopic head, the metal wear-resistant telescopic tube is used inside, which effectively prevents the gravel coal from abrading the telescopic head, and eliminates the damage caused by the high temperature of the pebble coal to the sealing rubber parts of the external telescopic head; To ensure the tightness of the telescopic part, the telescopic head with double-layer structure is adopted for the first time, which greatly increases the service life of the telescopic head.

 

● The multifunctional filtering and sealing compartment reserves the connection interface with the centralized discharge filter. Each furnace dust-free pebbles hopper discharge system shares one bleed filter (configured according to user requirements), which completely eliminates the surrounding environment pollution caused by the residual pressure discharge in the pebbles hopper