ABSTRACT
This chapter presents the available point-of-use (POU)/point-of-entry (POE) treatment devices for removal of various contaminants. POU/POE treatment is used to control a wide variety of contaminants in drinking water. Aesthetic parameters such as taste, odor, or color can also be improved with POU/POE treatment. Basic treatment techniques such as reverse osmosis, ion exchange, and activated carbon can be used to remove the contaminants from drinking water. Activated carbon removes contaminants from water by adsorption or the attraction and accumulation of one substance on the surface of another. Two important variables when considering a carbon system are contact time and breakthrough. Concern, arises that direct consumption of water from POU/POE carbon devices may cause a bacterial health problem while preventing a chemical health problem. Contaminant removal in a reverse osmosis process is obtained by passing contaminated water through a semipermeable membrane. The two membrane systems generally used in water treatment are reverse osmosis and ultrafiltration.
