Adsorption in Water and Used Water Purification

Adsorption is the adhering of substances from gases or liquids onto the interface of two phases, mainly onto solids. In water and used water purification, adsorption is applied for the removal of dissolved impurities. The most common process is application of activated carbon for removal of organic substances. But there are also special applications such as removal of Arsenic or other inorganic impurities using media other than activated carbon. Activated carbon can either be granular based or in the powdered form and its application depends on the treatment requirements and final water quality expectations. Activated carbon filtration (ACF) is mostly used as a polishing stage in water treatment processes and is gaining renewed focus in the recent years for its effectiveness in removing emerging contaminants called “micropollutants.” The process can be deeply understood if the relations governing the adsorption processes will be studied along with the different process schemes that are adopted in the water and wastewater domain. Hence, various design aspects of the ACF will be briefed along with important relations. Subsequently, three case studies would be presented which highlights the diverse areas where activated carbon is useful in tackling different contaminants across different areas of the globe.