Currently, two types of carbon are most often used for water filtration: powdered activated carbon (PAC) and granular activated carbon (GAC). PAC has a smaller particle size than GAC and is typically more efficient at removing a wide range of impurities from the water.
In most filters, the activated carbon is combined with a secondary element or media such as silver. The added components give the filter additional bacteriostatic properties.
Also known as “fixed-bed carbon filters,” GAC filters are typically cylindrical containers that hold particles of GAC. activated carbon suppliers australia Water is added to the container and as the water flows through the system, the loose carbon particles filter out impurities.
However, channeling is a common problem with GAC filters. As water enters the chamber, it automatically flows through the container by the path that presents the least resistance. This means carbon particles bypassed by the water are underutilized, reducing the overall efficiency of the filtering system.
GAC filters are also known for growing bacteria. As water flows down frequently traveled “channels” through the activated carbon, pockets of carbon and stationary water remain behind. These areas of relatively stagnant and contaminated water are ideal settings for bacterial growth.
Solid carbon block filters are densely packed blocks of PAC and GAC particles of varying sizes. Water is forced through the pores of the carbon block, and as it travels through the filter, the tiny carbon particles remove a wide range of contaminants.
The primary advantage of block filters over GAC filters is the elimination of channeling. With carbon block filters, the carbon particles are stationary and every particle is used to maximum effectiveness.dxdcarbon A wide range of contaminants is removed from the water — small pollutants are adsorbed by the carbon, while larger impurities are too big to pass through the pores of the block and are left behind.
More efficient and effective than GAC filters, carbon block filters do have one drawback — it takes more time for water to pass through solid block filters than through carbon bed filters, which means it isn’t practical for situations where you need a huge quantity of water filtered quickly, such as in municipal water systems. For many households, however, a carbon block filter provides more than enough filtered drinking water every day.