How to Choose Filter Bags for High-Temperature Conditions?

In industries such as steel, cement, metallurgy, chemical, and power generation, dust removal systems often operate in high-temperature, high-dust, and high-load environments for extended periods. Improper filter bag selection can not only shorten service life but also lead to decreased dust removal efficiency, increased system resistance, and even affect the stable operation of the entire equipment. Therefore, scientifically selecting industrial dust removal filter bags is crucial under high-temperature conditions.

1. Clarify the Specific Conditions of "High-Temperature Conditions"
Before selection, it is essential to understand the actual working conditions on site, and not just rely on the general statement of "high temperature." The following parameters usually need to be considered:

Continuous operating temperature and instantaneous maximum temperature
In some working conditions, the daily temperature is around 150℃, but the instantaneous temperature may exceed 200℃, which significantly affects the temperature resistance requirements of the filter bag.

Flue gas composition
Whether it contains acidic gases, alkaline gases, oil mist, or water vapor, as these will affect the corrosion resistance and aging resistance of the filter material.

Dust characteristics
Whether the dust is highly viscous or the particles are sharp will also affect the wear resistance of the filter bag.

2. Analysis of Commonly Used Industrial Dust Removal Filter Bag Materials for High Temperatures
Different filter materials have significantly different temperature ranges and applicable working conditions.  When choosing, you should not blindly pursue "the higher the temperature resistance, the better."

(1) PPS Filter Bags
Continuous operating temperature: 160–190℃
Advantages: Good acid and alkali resistance, high cost-effectiveness
Applicable scenarios: Coal-fired boilers, cement kiln tails, and other medium-to-high temperature conditions

(2) Aramid (Nomex) Filter Bags
Continuous operating temperature: Around 200℃
Advantages: Good heat resistance and wear resistance
Note: Not resistant to strong acids and hydrolytic environments

(3) PTFE (Polytetrafluoroethylene) Filter Bags
Continuous operating temperature: Above 240℃
Advantages: High temperature resistance, corrosion resistance, long service life
Disadvantages: Relatively high cost

(4) Fiberglass Filter Bags
Continuous operating temperature: 260℃
Advantages: Outstanding high-temperature resistance
Limitations: Poor flexibility, high requirements for installation and cleaning

3. Key Principles for Selection under High-Temperature Conditions
(1) Allow a "safety margin" for temperature resistance
The temperature resistance index of the filter bag should be 20-30℃ higher than the actual operating temperature to cope with operating condition fluctuations and avoid damage due to instantaneous over-temperature.

(2) Consider chemical stability comprehensively
In environments containing acid, sulfur, or high-humidity flue gas, simply being high-temperature resistant is not enough; industrial dust collector filter bags with stronger chemical stability must be selected.

(3) Pay attention to surface treatment processes
Under high-temperature conditions, it is recommended to choose filter bags with membrane coating or singeing treatment, which helps reduce operating resistance and improve dust removal efficiency.

4. Easily Overlooked Practical Problems
Many dust collection systems experience premature filter bag failure, not due to incorrect material selection, but because the following factors are overlooked:
Excessive temperature fluctuations during equipment startup
Unreasonable cleaning parameter settings
Condensation in the flue gas leading to filter bag clogging
Improper installation causing mechanical wear
These problems are difficult to avoid even with high-end industrial dust collector filter bags.

The core of filter bag selection under high-temperature conditions is not just "temperature resistance," but matching the overall operating conditions.
Only by fully understanding the temperature range, flue gas composition, and dust characteristics, and rationally selecting the material and structure, can industrial dust collector filter bags truly achieve stable, efficient, and long-lasting performance.