How to Improve the Dust Removal Efficiency of Boiler Baghouse Dust Collectors?

The dust removal efficiency of boiler baghouse dust collectors is directly related to environmental emission compliance and the service life of subsequent equipment. For boiler flue gas with high temperature, high humidity and high dust concentration, improving dust removal efficiency requires comprehensive optimization from pre-treatment, equipment configuration, operating parameters, daily maintenance and other aspects. The specific measures are as follows:

1. Optimize Flue Gas Pre-Treatment (Reduce Dust Load and Improve Flue Gas Quality)
Pre-treatment is the basis for improving dust removal efficiency. By reducing the dust concentration, removing large-particle dust and adjusting flue gas parameters, the load of the filter bag is reduced, and the dust capture effect is improved.
1. Add or upgrade pre-treatment devices: For boiler flue gas with high dust concentration (＞1000g/m³), install a cyclone dust collector or multi-tube ceramic dust collector as pre-treatment to remove large-particle dust (≥10μm), reduce the dust concentration entering the filter bag to below 500g/m³. For extremely high dust concentration (＞3000g/m³), adopt two-stage pre-treatment (gravity dust collector + cyclone dust collector) to further reduce the dust load.
2. Control flue gas temperature and humidity: Install a flue gas cooling device (heat exchanger, cooler) to control the flue gas temperature within the long-term temperature resistance range of the filter bag (e.g., PPS bags 160-180℃), avoid filter bag aging and damage caused by excessive temperature. Install a dehumidifier or demister to reduce the flue gas humidity to below 80%, prevent the filter bag from dampening and blocking, and ensure good air permeability.
3. Remove corrosive and viscous components: For flue gas containing corrosive gases (such as sulfur dioxide) or viscous dust, install an absorption device (alkaline spray tower) to remove corrosive components, or add a dust modifier to reduce the viscosity of dust, avoid dust adhering to the filter bag and affecting dust removal efficiency.

 2. Optimize Equipment Configuration (Improve Filtering Capacity)
Reasonable equipment configuration is the key to improving dust removal efficiency. By optimizing the filter bag, filter area, flower plate and other components, the filtering effect is enhanced.
1. Select high-efficiency filter bags: Choose filter bags with high dust removal efficiency and good matching with working conditions. For fine boiler dust (≤1μm), select filter bags with small pore size (such as PTFE coated composite bags, nanofiber composite bags), the dust removal efficiency can reach ≥99.99%. For high-temperature, high-humidity flue gas, select PPS or FMS filter bags with good air permeability and dust holding capacity; for corrosive flue gas, select PTFE filter bags to ensure stable performance.
2. Increase filter area appropriately: Increase the filter bag area by 10-20% on the basis of the standard configuration, reduce the filter wind speed (control ≤1.0m/min), extend the contact time between flue gas and filter bag, ensure that fine dust is fully captured, and reduce dust leakage. At the same time, it can reduce the dust accumulation speed of the filter bag, reduce the cleaning frequency, and avoid filter bag damage caused by excessive cleaning.
3. Optimize flower plate and filter cage:
The flower plate should be processed with high precision, smooth and free of burrs, to ensure tight fit with the filter bag mouth, avoid dust leakage from the gap. The filter cage should be made of galvanized steel or stainless steel, with uniform structure and no deformation, ensuring that the filter bag is fully expanded, the air flow is uniform, and there is no dead angle of dust accumulation.

4. Improve equipment sealing performance: 

Check and strengthen the sealing of the dust collector body, flower plate, inspection door, ash discharge valve and air duct. Replace aging sealing gaskets, tighten loose bolts, and repair air leakage points to avoid unfiltered dusty flue gas bypassing and discharging, which affects the overall dust removal efficiency.

 3. Optimize Operating Parameters (Ensure Effective Cleaning and Stable Operation)
Scientific operating parameters can give full play to the performance of the equipment, avoid ineffective operation and improve dust removal efficiency.
1. Adjust cleaning parameters reasonably: The cleaning system is the guarantee of filter bag performance. Adjust the spray pressure, cleaning frequency and spray time according to the dust characteristics and equipment resistance. For fine and viscous dust, set the spray pressure to 0.4-0.6MPa, the cleaning frequency to 20-40s/time, and the spray time to 0.1-0.2s/time, ensuring that the dust on the filter bag surface is completely removed without causing filter bag damage or dust re-entrainment. For non-viscous dust, appropriately reduce the cleaning frequency to avoid excessive cleaning leading to filter bag wear.
2. Control air volume and negative pressure: The air volume of the fan should be 10-20% higher than the actual flue gas volume of the boiler to ensure that the flue gas is completely captured and flows smoothly. The negative pressure of the equipment should be controlled within 1200-1500Pa. Too high negative pressure will cause dust to penetrate the filter bag, and too low negative pressure will lead to insufficient dust capture. Adjust the fan speed to maintain stable air volume and negative pressure.
3. Ensure the quality of compressed air: The compressed air for cleaning should be dry, pure and free of water, oil and impurities. Install an air dryer, oil-water separator and filter to remove water, oil and impurities in the compressed air, avoid blocking the pulse valve and spray pipe, and prevent the filter bag from being dampened and blocked, ensuring effective cleaning.

 4. Strengthen Daily Maintenance (Maintain Equipment Performance)
Daily maintenance is an important measure to ensure long-term high efficiency of the equipment. Through regular inspection and maintenance, potential faults are eliminated, and the performance of the filter bag and equipment is maintained.
1. Regularly inspect and replace filter bags: Check the filter bag every day for blockage, damage and aging. Clean the blocked filter bag in time, and replace the damaged or aged filter bag. For filter bags that have reached the service life, replace them in a unified manner to ensure that the filter bag has good dust removal performance.
2. Maintain the cleaning system: Inspect the pulse valve, solenoid valve, air bag and spray pipe regularly, clean the blocked components, repair the faulty parts, and ensure uniform and effective spray. Drain the water and oil in the air bag and air pipeline every day to maintain the quality of compressed air.
3. Maintain the ash discharge system: Ensure that the ash hopper is free of dust accumulation and hardening, and the ash discharge valve operates smoothly. Timely discharge the collected dust to avoid dust backflow and accumulation on the filter bag, which affects the air permeability and dust removal efficiency.
4. Clean the equipment and pipelines: Regularly clean the dust collector body, air duct and pre-treatment device, remove accumulated dust and debris, avoid blockage, and ensure smooth air flow.

 5. Adopt Intelligent Control (Real-Time Adjustment and Optimization)
Install an intelligent control system to monitor the operating parameters of the equipment in real time (flue gas temperature, humidity, dust concentration, equipment resistance, spray pressure, etc.), and adjust the operating parameters automatically according to the changes of working conditions, so as to maintain the high efficiency and stable operation of the equipment.
1. Install online monitoring devices: Install a flue gas online monitoring system to detect the dust concentration at the exhaust port in real time. If the concentration exceeds the standard, the system will alarm automatically, and adjust the cleaning parameters or prompt to check the filter bag.
2. Equip with intelligent adjustment function: The intelligent control system can automatically adjust the cleaning frequency, spray pressure and fan speed according to the equipment resistance and dust concentration, avoid manual adjustment errors, and ensure that the equipment operates in the best state.
3. Establish a fault early warning mechanism: The system can monitor the operating status of key components (pulse valve, solenoid valve, fan) in real time, issue an early warning when a fault is found, and remind operators to handle it in time, avoid fault expansion and affect dust removal efficiency.

 Summary
Improving the dust removal efficiency of boiler baghouse dust collectors is a systematic project, which needs to be combined with pre-treatment optimization, equipment configuration improvement, operating parameter adjustment, daily maintenance strengthening and intelligent control. Only by comprehensively considering the characteristics of boiler flue gas and the operating status of the equipment, and taking targeted measures, can the dust removal efficiency be stably improved, ensuring that the emission meets the environmental protection standards, and extending the service life of the equipment.