Activated carbon is one of the most effective and versatile filtration media used today. When incorporated into cartridge filters, it offers a practical and efficient solution for removing unwanted organics, chlorine, taste and odour compounds, and even some dissolved chemicals from process fluids. But how do these filters work, and where do they provide the most value?
What Is Activated Carbon and Why Is It Used in Cartridge Filters?
Activated carbon is a highly porous form of carbon processed to have a vast internal surface area — up to 1,000 m² per gram. This structure makes it ideal for adsorption (not absorption) — the process of molecules sticking to a surface.
Cartridge filters filled or impregnated with activated carbon media are designed to remove:
- Chlorine and chloramine
- Organic contaminants
- Taste and odour compounds
- Certain pesticides and solvents
- Some dissolved gases and volatile organic compounds (VOCs)
These filters do not generally remove particulates effectively, so they’re often used downstream of a depth filter or a pleated depth filter, which removes the particulate contamination.
Types of Activated Carbon Cartridge Filters
There are two main types of activated carbon used in cartridges:
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- Structure: Loose granules inside a cylindrical housing.
- Advantages: High dirt-holding capacity, longer life.
- Drawbacks: Lower surface contact time and potential for media channelling, which can radically reduce efficiency.
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- Structure: Fine carbon powder compressed into a dense block.
- Advantages: Greater adsorption efficiency due to longer contact time, better removal of finer organics and chlorine/chloramine.
- Drawbacks: Higher pressure drop and risk of clogging if not prefiltered.
Some filters also combine carbon with other media (e.g. ion exchange resins, depth media) for broader contaminant removal or flow stabilization.
Where Are Activated Carbon Filters Used?
These filters are used across a broad range of industries. Here are common applications:
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- Chlorine and taste/odour removal in bottling plants
- Ingredient water treatment for beer, wine, soft drinks
- Decolourisation in sugar syrups or juice processing
- Decolourisation of white spirit drinks (alcoholic or non-alcoholic)
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Pharmaceuticals & Cosmetics
- Removal of organics and chlorine before reverse osmosis systems
- Purification of process water for cleaning and formulation
- Polishing step to ensure odour-free cosmetic base liquids
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Chemicals & Petrochemicals
- Dichlorination of process water to protect sensitive RO membranes, resins or catalysts
- Removal of trace hydrocarbons and solvents in high-purity processes
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- Taste and odour improvement at point-of-entry or point-of-use
- Final stage polishing before distribution
Design Considerations
When specifying an activated carbon cartridge filter, consider the following:
- Flow Rate vs. Contact Time: Adsorption is time dependent. Higher flow rates reduce contact time and performance. Always check rated service flow (L/min or L/hr) vs. maximum flow. Typically, 10” block carbon filters have a maximum flowrate of 3.8 l/min per 10” module.
- Pressure Drop: Carbon block filters have higher initial pressure drops than GAC filters.
- Chlorine Load: If targeting chlorine removal, match the filter capacity (mg/L or ppm) to the expected load and changeout frequency. A typical manufacturers capacity is 22,700 litres per 10” module at a flow of 3.8 l/min for chlorine, odour and taste removal.
- Pre-filtration: Always use a depth filters or pleated depth filters upstream to protect the carbon filter from fouling.
- Cartridge Format: Standard DOE (double open end), SOE (single open end), and sanitary-style filters are all available.
Limitations of Carbon Filters
Activated carbon cartridges are effective but not universal:
- They don’t remove dissolved salts, heavy metals, or pathogens.
- Their effectiveness drops sharply once saturation is reached — replacement schedules are essential.
- In pharmaceutical and biotech environments, they may not meet stringent validation requirements without supporting documentation.
Activated carbon cartridge filters offer a powerful and flexible method for removing chlorine, taste, odour, and organic contaminants across a wide range of industries. Selecting the right filter depends on your process needs — whether it’s high-flow water pre-treatment or polishing a final product stream. Proper pre-filtration, system sizing, and regular replacement are key to getting the best performance from these filters.
We offer a range of carbon filter solutions at PoreFiltration; Carbon Block Filters, Carbon Felt Filters, Carbon Filter Sheets and Oil Removal Filters, and were also available to help with any questions you may have on activated carbon filtration, just give us a call or send us an email - we're here to help you make the best choice for your filtration needs.
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