From Activated Carbon
In many industrial processes, toxic gaseous pollutants are emitted. Generally, these substances should not be released. Most of the toxic pollutants in the exhaust air are solvents, which are required for the production of consumer goods. For the removal and separation of these solvents (mostly hydrocarbons, and chlorinated hydrocarbons), the use of activated charcoal has been proven. Depending on the initial concentration of the pollutant one-way activated carbons are used or activated carbons are applied, that can be regenerated in solvent recovery plants.
Pelletized activated carbons are used in fixed bed filters. The contaminated air flows through the activated carbon bed in one direction (usually upwards). Criteria for filter bed design: Flow rate: 0.1 - 0.5 m / s Contact time: about 0.1 - 0.5 seconds Height of the fixed bed: at least 0.5m, mostly 1 -3 m The flow resistance depends on the pellet diameter of the activated carbon and the linear flow velocity. For a typical pressure loss curve for a 4 mm pelletized activated carbon, please refer to the following diagram.
Pelletized activated carbons are characterized by their diameter:
- 0.8 mm: Silcarbon 0.8supra
- 1.5 mm: Silcarbon SIL-15 extra, SC15,
- 2 mm: Silcarbon SIL20
- 3 mm: Silcarbon SIL-40-3S
- 4 mm: Silcarbon SIL-40, SC-40, SC-44 and FT40 special
There are several areas of application
- For 0.8, 1.5 or 2 mm pellets:
- Wastewater treatment
- Cleaning chemicals
- Air cleaning (small filter units)
- for 3 or 4 mm Pelletized activated carbons:
- Air and gas purification