With widespread pollution of water bodies, water purification has become a necessity of modern life. Access to clean, safe drinking water protects your family’s health, which is why a water purifier is one of the most important appliances in the home, wherever you live.
There are many water purifiers on the market to suit different needs, and what they all have in common is that they use several filters at each stage of the purification process. One of these is the carbon filter.
Here we look at what activated carbon for water treatment does. Read on to find out.
What is a carbon filter?
A carbon filter is one of the most widely used filters for water purification. It can be used in many devices whose sole purpose is to clean water, such as shower filters, fridge filters and reverse osmosis units.
Carbon filters are made from a carbon source. The most common sources are coal, coconut shells and hardwood and softwood. Coconut shell is a popular choice because it is renewable and easy to obtain.
In fact, any natural material with a high carbon content can be turned into activated carbon by heating it to high temperatures, which breaks down its molecular structure.
What does carbon do in water purification?
Carbon filters have long been used to remove contaminants from water. These are the features that make them effective.
A carbon filter removes unwanted contaminants and chemical compounds such as chlorine, pesticides and other volatile organic compounds, making the water safer.
Carbon filters also remove odours and improve the taste of the water. They work by adsorption: contaminants in the water are attracted to the surface of the carbon and stick to it. As the water passes through the filter, the carbon particles remove contaminants together with the compounds that cause odours.
Pre-RO carbon filter
This stage removes as many impurities and contaminants as possible from the source water before it reaches the reverse osmosis membrane for further purification.
Its large surface area allows contaminants and impurities to attach to the carbon particles, so most contaminants are removed from the source water.
The reverse osmosis membrane then has fewer impurities to deal with, which extends its service life. The carbon stage is particularly useful for protecting the membrane from chemicals, such as chlorine, that would quickly damage it, and so reduces maintenance and repairs.
Pre-RO carbon filters do not remove total dissolved solids, heavy metals or bacteria. Further stages, such as reverse osmosis and UV, are therefore needed to make the water safe to drink.
Post-RO carbon filter
After the water has passed through reverse osmosis and UV, a second carbon filter is added as the final polishing stage: the post-RO carbon filter.
It is typically made from high-quality coconut shell carbon with a large surface area for adsorption. This final filtration improves water quality by removing any remaining odours and improving the taste.
Why are carbon filters used in water purification?
Activated carbon has many uses across industries, from gold mining and food manufacturing to water treatment plants. Today, water treatment is its most common application, for several good reasons:
- Once converted into activated carbon, organic materials with a high carbon content can remove unwanted contaminants from water.
- Activated carbon filters effectively remove pesticides, chlorine and odour-causing compounds from raw water and wastewater.
- They remove unwanted substances while leaving beneficial minerals in place.
- They are inexpensive and relatively easy to install, maintain and clean.
- They can be combined with other filtration systems to improve water quality.
Conclusion
Activated carbon filters are one of the most effective filtration options for purifying water. They remove a wide range of contaminants and improve the taste of the water. Used with reverse osmosis or ion exchange systems, they extend the life of the RO unit by protecting the membrane from contaminant loading.
With so many uses, activated carbon is one of the most widely used water purification methods. For the right water treatment solution for your home or business, see our activated carbon or contact KEIKEN.
