waterfiltration

Water filtration refers to processes that remove particles, pathogens, and chemicals from water to produce a safer and more palatable supply. The goal is to reduce turbidity, remove contaminants, and improve taste and odor, while maintaining acceptable mineral content where appropriate.

Filtration works through physical barriers, adsorption, chemical reactions, and biological activity. Particulate matter is trapped by porous media; dissolved substances may be removed by adsorption onto activated carbon or ion-exchange resins; biologically active filters can degrade organic compounds and nitrates.

Common filtration methods include mechanical filtration with screens or depth filters, granular media filtration using layers of sand, coal, and gravel, activated carbon filtration for organic compounds and chlorine removal, and membrane filtration such as microfiltration, ultrafiltration, nanofiltration, and reverse osmosis.

Filtration systems are typically organized in stages, starting with pretreatment to remove large debris, followed by one or more filtration barriers, and ending with post-treatment such as disinfection (chlorination, UV) and sometimes pH adjustment.

Applications range from municipal drinking water plants and industrial process water to household point-of-use units and wastewater treatment facilities.

Quality control involves monitoring turbidity, residual disinfectant, and compliance with contaminant limits; filters require regular maintenance, backwashing, or replacement according to manufacturers' guidance.

Limitations include incomplete removal of some dissolved contaminants, energy use, waste brine from certain membranes, and the need for skilled operation.