What Does a Carbon Filter Do for Water?

Clean water is essential for our health and well-being. The problem is that well water is often full of contaminants and even municipal water has content that you may not like.

Water purification systems often use a number of filters for different purposes, but carbon filters are the most common and most effective. The Environmental Protection Agency (EPA) recommends carbon filtration for water treatment, and it is a medium that has increasing use.

How Carbon Filters Work?

Carbon filters have traditionally been made from peat or bituminous coal, but these days are more commonly made from coconut shells due to them being a sustainable source. The material is heated in a vacuum to 1,000 degrees so impurities are burnt off and is then treated with steam at 1,600 degrees. This latter process causes the resulting carbon granules to open further pores and cracks, so the surface area is increased. The aim is to create a material that has maximum exposure to contaminants. Typically, one pound (450 grams) of activated carbon has a surface area equivalent to 100 acres.

The removal of contaminants is by a process known as adsorption, where the contaminants are attracted to the carbon’s surface and become trapped in the pores. Water flows through the carbon, leaving behind the contaminants, and moves on to the next stage in a purified form. Some chemicals aren’t attracted to the activated carbon but are instead converted by it; chlorine, for example, is converted to salt.

There are two basic types of activated carbon filters:

• granulated active charcoal (GAC) where the filters contain loose granules, about 1mm in diameter. These filter contaminants are not detected by other materials although some may get through. They are sometimes used in the final process to improve taste and smell.
• carbon block filters have a binding agent added to the granules to prevent them from moving and are heated to form the blocks. These are compressed so water flow rates may be reduced, especially for smaller micron sizes although these will remove more contaminants.

The Contaminants that are Removed

Activated carbon filters can remove a variety of contaminants, which include:

• up to 95% of chlorine that is added by water companies as a disinfectant but can cause sickness and has an unpleasant taste and smell
• over thirty chlorine byproducts such as VOCs and THMs
• fourteen of the most common pesticides and twelve of the most common herbicides
• up to 90% of lithium, a trace metal that has potential health risks
• pharmaceuticals that get into water sources, including wells
• PFOS that has various commercial uses but can be dangerous to human health.

It is important to safeguard the health of your family by ensuring they have the purest water available. Our range of water treatment systems incorporates a number of methods, including active carbon filters, to ensure your water is pure and fresh. We can arrange a test of your water to see what it contains and then install the most suitable system.