What is a bag filter?
The bag filter effectively collects, processes, and utilizes thick smoke, improves the workshop environment, and makes the gases emitted into the atmosphere clean and harmless. The filtration mechanism is used, where when the dusty airflow passes through the filter cloth, particles larger than the gap in the filter cloth settle due to gravity or are blocked by the filter cloth due to inertia; Particles with smaller gaps than the filter cloth, due to collision with the filter cloth or adsorption by the filter cloth fibers, stay on the surface and gaps of the filter cloth. Then, the dust adsorbed on the filter cloth is blown down to the dust collection bin by the action of the soot blowing valve.
The bag filter equipment has two compartments, each containing six blowing solenoid valves, one cylinder lift valve, one booster air compressor, and one dust collection fan. The system is divided into three blowing triggering methods: manual, timed, and differential pressure.
PLC control system configuration
The main control system of the equipment adopts the Huceen E7-200smart PLC, which communicates with the touch screen through the RS485 communication port of the CPU body. The DO of the body controls the start and stop of the soot blowing solenoid valve, cylinder lifting solenoid valve, and motor. The pressure and temperature of the dust removal chamber are detected through the extended analog input module, and the frequency of the air compressor and dust collection fan is controlled by the extended analog output module.
PLC real shot diagram
Soot blowing action: It is necessary to set the blowing parameters in advance on the touch screen: cylinder lifting time, spraying time, spraying interval time, warehouse interval time, and cycle time.
When starting the soot blowing action, execute it sequentially from chamber 1 to chamber 5. Firstly, lift the cylinder of chamber 1, and according to the set time, the 10 soot blowing solenoid valves in chamber 1 will act in sequence according to the set "spray interval time". After the execution is completed, switch to chamber 2 according to the interval time, and execute it sequentially to chamber 5. Then, according to the set "cycle time", perform the soot blowing action in chamber 1 again.
Soot blowing mode:
1. Manual triggering: An operator clicks a button in the HMI to trigger soot blowing.
2. Timing trigger: Periodically trigger soot blowing according to the set time.
3. Pressure difference triggering: Install a pressure difference sensor at the inlet and outlet of the smoke and dust pipeline, and trigger soot blowing based on the set pressure difference. (When dust is covered in the filter bag, the ventilation effect decreases, which will cause an increase in the pressure of the smoke and dust inlet)
Actual photo of electrical cabinet