Pelletized Activated Carbon
Pellet activated carbon is a porous adsorbent formed into cylindrical particles. Their diameter and shape affect the spaces between particles and airflow through the bed.
Retention of organic vapors depends on the carbon pore structure. Chemically impregnated grades also exist for specific gases; a cylindrical shape alone does not indicate such treatment.
Technical Specifications
| Physical form | Extruded cylindrical pellet |
|---|---|
| Feedstock | Coal based |
| Pellet diameter options | 3 / 4 mm |
| BET surface area | 931 m²/g |
| Iodine number | 900–1125 mg/g |
| Bulk density (ASTM D2854) | 473–521 kg/m³ |
| CTC adsorption | 60% |
| Ash content | 12.3% |
| Moisture | 4.5% |
| Hardness | 95% |
Application and use
- In industrial exhaust treatment, gas passes through a pellet carbon bed to reduce adsorbable organic vapors and odors.
- Suitable grades are used in ventilation and paint-booth exhaust systems for VOC control.
- In solvent recovery, a compatible carbon grade retains solvent vapor before a separate desorption stage recovers it.
- Bed design considers airflow resistance and the required contact between the gas and carbon.
Frequently asked questions
Can a standard pellet replace an impregnated carbon?
The same pellet shape does not establish equivalent removal. Some gases require a chemically treated or purpose-designed carbon grade.
Does capturing solvent make it ready for reuse?
No. Reuse requires suitable desorption and solvent separation in addition to adsorption.
Does high inlet humidity affect performance?
Yes. Water vapor or condensation can reduce adsorption in the pores. Assess gas humidity and any pretreatment for the actual process.
How can we tell when the gas carbon needs changing?
Monitor the target compound at the gas outlet for breakthrough. The interval depends on inlet loading and the required outlet level.
Is pellet diameter enough to choose an equivalent replacement?
No. Diameter affects pressure drop; pore structure, target gas and operating conditions also determine suitability. Compare the existing bed and gas data together.