Activated Carbon can be manufactured from many materials containing high carbon content such as coconut shell, wood, coal, bituminous, coir, lignite, peat, petroleum pitch etc. Carbonaceous materials can be activated using two methods, steam activation and chemical activation.
Forms of Activation are
Steam Activation
In this process the material is activated with steam at very high temperature. The chemical reaction between the carbon and the steam take place at the internal surface of the carbon. Steam activation enlarges the pore structure and thus increases the internal surface area. It is the most widely used process to activate carbonaceous materials. It is considered as the best pollution free method of activation.
Granular Activated Carbon (GAC)
Granular activated carbon is defined as the activated carbon being retained on a 50-mesh sieve. They have the advantages of being harder and more long-lasting than powder activated carbon (PAC), clean to handle, purify larger volumes of gas or liquid of a consistent quality, and can be reactivated and reused many times. Granules Activated Carbon is widely used in drinking water, industrial water, brewing, waste gas treatment, decolorization, desiccant, gas purification, etc.
Chemical Activation
This type of activation is only useful for the carbonization of wood, sawdust or peat. In chemical activation the raw material is mixed with an activating agent such as phosphoric acid that swells the material and open up the cellulose structure. It is then carbonized and dried in a rotary kiln at low temperature. It dehydrates the raw material resulting in the amortization of the carbon, thereby creating high porous structure. At NCPL we follow steam activation method since it is the most environmental friendly method of activation process.
According to different shapes, activated carbon can also be divided into several types.
Powdered Activated Carbon (PAC)
Powdered activated carbon (PAC) is made from organic materials with high carbon contents such as wood, lignite, and coal. PAC typically has a diameter of less than 0.1 mm and has an apparent density range between 23 and 46 lb/ft3. Advantages of powdered activated carbons are their lower processing costs and their flexibility in operation Powder carbons are widely used in food, beverage, medicine, tap water, sugar, oil and other industries in brewing, sewage, treatment, power plants, e lectroplating, etc.
Pellets
Pellets are activated carbon compressed into a cylindric shape and have a wide variety of uses. Removing contaminants such as volatile organic compounds (VOCs) and mercury from natural gas as well as controlling odour. Pelletized activated carbon is made from high-quality coal or coconut shell by extruding the activated carbon into cylindrical particles with a diameter range of 0.9 – 8 mm. Activated carbon pellets are suitable for toxic gas purification, waste gas treatment, industrial and domestic water purification treatment.
What equipment should equipped in a activated carbon factory?
A steam activation factory should be equipped its factory according to the procedure
- 1. Carbonizing furnace, change the biomass into charcoal first.
- 2. Charcoal treatment, meshing and crushing.
- 3. Steam activation kiln.
- 4. Raw AC. Treatment system, crushing and milling, also including acid washing or other procedure.
- 5. A lab for testing.