As a dust removal system, boiler bag filters and related equipment require special attention in maintenance.
If the boiler bag filter is not used for a long time, maintenance measures must be taken to prevent the bag from being damp, compacted, and corroded. At the same time, all inlet and outlet valves of the filter should be closed. During the shutdown period, open the inlet and outlet valves at regular intervals, use the chimney for natural ventilation for 4 hours, or turn on the electric heater for heating for 8 hours to remove moisture from the dust collector and keep it dry.
When the boiler bag filter is shut down, if the shutdown time is short, the filter bag dust should not be cleaned. Attention should be paid to the insulation of the boiler bag filter. If the shutdown time is long, all filter bags should be cleaned, and the residual acidic gas in the boiler bag filter should be removed completely by the induced draft fan.
(1) The boiler bag filter should be operated and maintained by a dedicated person. Regularly lubricate the rotating parts. Master the performance and structure of the dust collector from multiple aspects, promptly deal with problems, and confirm the normal operation of the dust removal system. The on duty personnel shall record the operation status and relevant data of the shift. If smoke and dust are found at the exhaust outlet, it indicates that the filter bag is leaking. During maintenance, stop the air in each room and open the upper cover. If dust is found at the bag opening, it indicates that the filter bag is damaged and needs to be replaced or repaired.
(2) The resistance of the boiler bag filter is generally between 1200-1500Pa, and the cleaning cycle is adjusted using the set switch in the control cabinet according to the resistance situation.
(3) The air filter of the compressed air system should be drained regularly, and the airbag drain valve should be drained regularly. Even if there are gas storage tanks, they should be drained regularly.
(4) The control valve should be inspected by specialized personnel, and the solenoid valve and pulse valve should be checked regularly.
(5) When starting the boiler, it mainly relies on fuel oil. Due to the low temperature inside the furnace, the temperature of the flue gas, boiler bag filter, and pipeline is also low, and the oil mist content is high, which is prone to condensation. There are two preventive measures:
One method is to use a bypass flue, where the flue gas directly enters the front header of the induced draft fan without passing through the boiler dust collector. When the boiler cuts off oil or burns coal powder or fuel reaches a high load, and the flue gas reaches a certain temperature, the bypass air door is gradually closed, and the boiler bag filter enters normal operation.
Another method is to not set up a bypass flue, and before starting the boiler, fly ash is sprayed into the bag filter without blowing back to clean the dust, so that a layer of dust adheres to the surface of the filter material. In this way, oil mist in the flue gas is prevented from directly contacting the filter bag, avoiding damage to the filter bag.
