The pressure difference of dust removal equipment is a core indicator reflecting the operating status. Under normal working conditions, the pressure difference of most dust removal equipment remains stable at 800-1500Pa. Once the pressure difference is too high or too low, it not only leads to a decrease in dust removal efficiency and an increase in energy consumption, but may also cause damage to equipment components, affecting production continuity. Focusing on the core causes and practical solutions of abnormal pressure differentials, it is suitable for various industrial dust removal equipment such as bags, filter cartridges, electrostatic precipitators, and cyclones, providing objective technical references for overseas industrial users.
 

1、 High pressure difference: reasons and solutions for excessive resistance
The pressure difference remains above 1800Pa and cannot fall back, which is a typical problem of excessive resistance and is often related to dust accumulation and airflow obstruction.

1. Core reasons
Filter material blockage: Dust adhesion and agglomeration on the surface of the filter bag/filter cartridge, or fine powder infiltration into the interior of the filter material causing micropore blockage, commonly found in high humidity and high viscosity dust conditions.
Dust cleaning system failure: Pulse valve leakage, insufficient blowing pressure (below 0.4MPa), unreasonable dust cleaning timing setting, resulting in ineffective dust removal.
Blocked airflow channel: The ash hopper is filled with dust, the air inlet guide plate is deformed, and the filter bag/cylinder is installed askew, causing poor airflow circulation.
Improper selection of filter materials: Hydrophobic filter materials were not used in low-temperature and high humidity scenarios, or ordinary room temperature filter materials were used in high-temperature conditions, resulting in rapid degradation of filter material performance.

2. Solution skills
Emergency handling: Immediately stop the machine to clear the dust accumulation in the ash hopper, check the compressed air pressure of the ash cleaning system, and adjust it to 0.4-0.6MPa; Activate manual strong cleaning mode and perform centralized spraying on the filter material.
Targeted investigation: If the pressure difference is still high after strong cleaning, disassemble and check the status of the filter material - if there are adhesive lumps, they need to be blown back with compressed air (low pressure 0.3MPa), and if they are damaged, they should be replaced directly; If the pulse valve leaks, the diaphragm needs to be replaced. If the spray pipe is blocked, it should be disassembled and cleaned.
Adaptation and adjustment of working conditions: Install ash hopper heating device in high humidity areas (temperature 5-10 ℃ above dew point), replace PTFE membrane filter material in high viscosity dust scenarios to avoid dust adhesion.
Long term optimization: Reset the cleaning timing, shorten the spraying interval (5-8 minutes/time) when the dust concentration is high, and avoid excessive dust accumulation.

2、 Low pressure difference: Reasons and solutions for seal failure
Continuous pressure drop below 600Pa or sudden drop in the short term is often related to airflow leakage and filtration function failure, which can be easily overlooked but pose significant hazards.

1. Core reasons
Damaged filter material: The filter bag/cartridge is torn, the stitching falls off, or the filter cartridge film is damaged, causing the airflow to penetrate directly without filtration.
Aging of seals: The sealing gasket of the equipment maintenance door and the sealing ring of the filter bag mouth have hardened and cracked, or the flange connection is not tightly sealed, causing air leakage.
Equipment structural failure: Wear and perforation of cyclone dust collector cylinder wall, short circuit of electrostatic precipitator electric field, resulting in airflow short circuit, unfiltered process.
Abnormal detection: The differential pressure gauge sensor is blocked or damaged, and the data is distorted and misjudged.

2. Solution skills
Leakage location: Turn off the power supply of the equipment, introduce compressed air (0.2MPa) into the interior, and apply soapy water to the inspection door, flange, filter bag interface, and other parts. The bubbling area is the leakage point; Alternatively, auxiliary judgment can be made through dust concentration detection at the discharge outlet (the concentration will sharply increase during leakage).
Component replacement: Replace the damaged filter material immediately, and replace the aging sealing gasket with a model suitable for the working conditions (high-temperature resistant silicone gasket for high temperature, fluororubber gasket for corrosive scenarios); The perforation of the cyclone dust collector cylinder wall needs to be repaired by welding or replaced with wear-resistant lining, and the short circuit of the electrostatic precipitator electric field needs to clean the electrode dust or replace the electrode plate.
Testing and Calibration: Disassemble the differential pressure gauge sensor, clean the internal dust, calibrate the accuracy with a standard instrument, and replace it with a sensor of the same specification if it is damaged.
Installation review: Reinstall the filter material to ensure that the filter bag/cartridge is tightly fitted to the slot. After closing the access door, tighten the bolts to avoid sealing failure caused by improper installation.

3、 Key points of abnormal pressure difference in different types of dust removal equipment
1. Bag filter
High frequency issues: clogged filter bag, ineffective pulse valve blowing, aging sealing gasket.
Key points of investigation: Priority should be given to checking the status of the filter bag and the ash cleaning system. In high humidity conditions, additional checks should be conducted on whether the ash hopper has accumulated water and clumps.

2. Filter cartridge dust collector
High frequency issues: dust accumulation inside the folded filter cartridge, misalignment of the spray tube, and damage to the filter cartridge.
Key points of investigation: Disassemble the filter cartridge to check the cleanliness of wrinkles, adjust the angle of the spray tube to ensure that the airflow covers the entire filter surface.

3. Electrostatic precipitator
High frequency issues: electric field short circuit, electrode dust accumulation and nodules, airflow distribution plate blockage.
Key points of investigation: detect the voltage and current of the electric field, clean the dust accumulation on the electrodes and distribution plate, and ensure the normal operation of the electric field.

4. Cyclone dust collector
High frequency issues: wear and leakage of the cylinder wall, blockage of the ash hopper unloading valve, and deformation of the guide plate.
Key points of investigation: Check the integrity of the cylinder wall and the discharge situation of the ash hopper, correct the angle of the guide plate to ensure stable airflow.

4、 Preventive measures: Key operations to reduce abnormal pressure differentials
Regular inspection: Record pressure difference data daily and promptly investigate any fluctuations exceeding ± 200Pa to prevent minor issues from escalating.
Filter material maintenance: Regularly replace the filter material according to the working conditions (6-8 months for room temperature drying scenarios and 3-5 months for high humidity and high viscosity scenarios) to avoid exceeding the expiration date.
Cleaning system maintenance: Check the pulse valve, spray pipe, and compressed air pipeline weekly, and clean the sensors and differential pressure gauge monthly.
Adaptation to working conditions: Select corresponding filter materials and seals based on the temperature, humidity, and dust characteristics of the flue gas to avoid abnormalities caused by "mismatch".

The core solution logic for abnormal pressure difference is to first identify the cause and then handle it in a targeted manner, without blindly replacing equipment components. By mastering the above troubleshooting techniques, over 80% of abnormal pressure differences can be quickly resolved, ensuring the stable operation of dust removal equipment. In practical operation, it is necessary to flexibly adjust according to the equipment type and specific working conditions, and if necessary, professional testing tools can be used to assist in judgment.