Activated carbon is one of the most widely used water treatment and filtration methods in the world, and it’s found everywhere from household filters to industrial water treatment systems. But not all activated carbon systems are the same, and choosing the wrong type for your application can mean paying for performance you don’t need.
In this blog, we will detail everything you need to know about how activated carbon works, the different types available, and how to choose the right one for your application.
What is Activated Carbon?
Activated carbon is a form of carbon that has been processed to be extremely porous, giving it a huge internal surface area relative to its size. It doesn’t filter contaminants out mechanically as a sediment filter would; instead, it works through a process called adsorption.
As water passes through the carbon bed, organic compounds and certain chemicals are attracted to the porous surface and stick to it, which removes them from the water supply. Activated carbon is therefore especially effective at removing chlorine, chloramine, pesticides, and a wide range of volatile organic compounds (VOCs) that affect the taste, odour, and clarity of water.
Types of Activated Carbon Filters
Granular Activated Carbon (GAC)
This is loose, granular carbon packed into a filter housing or cartridge. Water will flow around and through the granules for good general-purpose contamination removal. GAC filters have a lower pressure drop, so this makes them a great choice for applications where flow rates matter.
Carbon Block Filters
Finely ground activated carbon powder is compressed into a dense, solid block. This creates a tighter, more uniform pore structure, which forces water to travel through a maze of carbon rather than around it. This means it can be moulded into cartridges, which are more convenient for point-of-use applications.
Carbon Fibre
Carbon fibre is a more advanced option that uses powdered activated carbon embedded in a synthetic fibre matrix. This combines absorption with depth filtration in a single stage in order to reduce pressure drops while removing both sediment and chlorine at once. This is a great choice where space or complexity is a concern.
Benefits of Activated Carbon
- Broad contamination removal – activated carbon effectively removes chlorine, chloramines, pesticides, and VOCs.
- Improved taste and odour – one of the most noticeable benefits is the removal of foul tastes and odours, particularly in the food and beverage industry.
- Low energy process – unlike other filtration methods like reverse osmosis, activated carbon filtration doesn’t require pressure-driven membrane separation.
- Flexible applications – activated carbon is suitable as both point of entry (POE) and point of use (POU) filters.
- Protects downstream equipment – removing chlorine and organics ahead of membranes and other treatment stages extends the life of the wider system.
How to Choose the Right Activated Carbon Filter
Before choosing a filter, it’s worth identifying exactly what you need to remove. Activated carbon is effective at removing chlorine, chloramine, taste and odour, and organic compounds, but each application will have its own priorities. That’s why you should ask yourself:
- What contaminants am I targeting? Chlorine, taste and odour, and general organics are handled well by GAC or carbon block. Where PFAS is the priority, you should look for carbon media specifically validated for it, as not all activated carbon performs equally.
- How much contact time does my system allow? Adsorption isn’t instant – water needs time in contact with the carbon for contaminants to attach to the surface. Granular carbon offers a lower pressure drop and faster flow but less contact time per pass.
- What’s the scale of my application? A large commercial or industrial site may need a multi-stage system capable of processing thousands of litres per hour, while a smaller application might only need a compact carbon cartridge. The sizing matters as it could impact costs, capacity, and replacements.
- Does the water need further treatment after? Activated carbon is widely used as a pre-treatment stage ahead of reverse osmosis – it removes the chlorine that would otherwise damage RO membranes. If your system includes downstream treatment, a carbon filter needs to be selected and sized with that in mind.
- How will I maintain my system? Every activated carbon filter has a finite absorption capacity. This means once it’s exhausted, contaminants will pass through untreated. You should therefore consider how easy the filter is to monitor, change or replace for your business and how it fits into your schedule.
Talk to the Experts
Fileder has decades of experience in filtration, and offers a wide range of WRAS-approved activated carbon products from GAC and carbon block cartridges to advanced carbon fibre in order to suit a range of applications across industrial, food and beverage, life sciences, and everyday settings.
If you’re not sure which activated carbon is right for your application, contact us today and one of our technical specialists can help you find the most suitable, cost-effective solution.
