Activated carbon in water and wastewater treatment

Activated carbon (or sometimes known as active carbon) is an adsorption process used in both water and wastewater treatment applications. Adsorption processes are commonly used in municipal drinking water treatment to remove synthetic organic compounds (SOCs), taste and odor-causing, color-forming organics, and disinfection by-product (DBP) precursors.

Industrial waste streams often contain many impurities such as dissolved and undissolved substances, easily degradable or persistent organic substances, heavy metals, and salts. Activated carbon eliminates these unwanted substances and is normally used in a last treatment step as a  last ‘polish’.

Activated carbon removes pollutants

During the adsorption process, dissolved species diffuse into the porous solid granule and are then adsorbed onto the extensive inner surface of the granule. A key feature for adsorbents is a high degree of porosity within the adsorbent granules. This means that the interior surface at which adsorption can occur is vast.

Activated carbon is produced from natural, carbonaceous materials with high temperatures and steam. Depending on the material used for production, the distribution of the pore size differs.

The four materials shown in the figure are only a few of the dozens of different activated carbon types available with varying pore sizes (Å = Ångstrøm = 0.1 nm). It is therefore important to have a basic idea of what needs to be removed from the wastewater, so the right type of carbon can be chosen. As shown in the figure, the pore size distribution various significantly.

Activated carbon is slowly saturated with absorbent over time, and must be replaced and discharged when fully saturated.

Aquarden will assist you in choosing the right type of carbon for your wastewater application.