Special Requirements for the Selection of Honeycomb Ceramic Pore Size in Viscous and Oily Exhaust Gases
Briefly introduces the special requirements for the selection of honeycomb ceramic pore size in the case of viscous and oily exhaust gases.
Special Requirements for the Selection of Honeycomb Ceramic Pore Size in Viscous and Oily Exhaust Gases
Tar and viscous substances in sticky, oily exhaust gases (such as asphalt fumes, paint mist, and coke oven gas) gradually deposit within the pores of honeycomb ceramic pores, leading to blockage. The core of pore size selection is striking a balance between ensuring heat recovery efficiency and extending the unclogging cycle.
Blocking Mechanisms
Condensation Deposition: High-boiling-point organic matter in the exhaust gas condenses into a liquid state when the temperature is below the dew point, adhering to the pore wall surface and gradually reducing the pore size until the channel is completely filled.
Particulate-Viscous Composite Scaling: Solid particles (carbon black, dust) are "adheded" to the pore wall by sticky substances, continuously accumulating to form a dense scale layer. The blockage rate is much faster than simple condensation, and it is extremely difficult to remove.
The Core Trade-off in Pore Size Selection
Parameter | Large Cell Size (100–200 cpsi) | Small Cell Size (300–600 cpsi) |
Clogging Resistance | Good (large dust-holding capacity) | Poor (prone to clogging) |
Heat Recovery Efficiency | Lower | Higher |
Cleaning Interval | Long | Short |
For viscous exhaust gases, a sufficiently large pore size must be prioritized; excessively high pore density should not be chosen in pursuit of high efficiency. The downtime losses due to blockage far outweigh the losses from a slight decrease in efficiency.
Recommended Pore Sizes for Different Exhaust Gas Types
Exhaust Gas Type | Recommended Cell Density | Guiding Principle |
Clean flue gas | 300-400 cpsi | Efficiency prioritized |
Contains trace oil mist | 200-250 cpsi | Balanced approach |
Contains tar/pitch/paint mist | 100-200 cpsi | Anti-clogging prioritized |
Supporting Measures
Airflow Distribution: Install a distribution plate at the inlet to avoid localized concentrated impact.
Temperature Control: Maintain wall temperature above the dew point to delay condensation.
Pre-dust Removal: Install cyclone or wet dust collectors to reduce complex scaling.
Summary
The requirements for selecting the pore size of honeycomb ceramics for viscous and oily waste gases can be summarized as: prioritizing anti-clogging while considering efficiency. Select 300-400 cpsi for clean flue gas, 200-250 cpsi for oily waste gas, and 100-200 cpsi for tar/asphalt/paint mist. In the treatment of viscous waste gases, flow is more important than efficiency. We are a Chinese supplier of honeycomb ceramics. For more information, please contact us via email at annayu@169chem.net or WhatsApp at +8618909016373.