The introduction of high rate water filter design makes new water filtration applications possible.  The effectiveness of these designs increases industry’s ability to conserve, treat and recycle large amounts of water.

Older sand filter systems depend on bacterial action for water purification, while rapid sand filters, which operate on a surface effect principle, make use of disinfectants and coagulants to accomplish the same objective.  Extensive investigative research of filter media and improved coagulants have made high-rate filtration practical and efficient.  A wide variety of high-rate filter types using downflow, upflow, center injection and radial outward flow have been developed.  However, the downflow type has become the most popular and seems to be the most versatile and reliable.

The backwash cycle in newer filters makes them perfect for those applications in which heavy loads cause short cycles.  The filter’s ability to be backwashed rapidly, using less clean water makes it very versatile for a wide range applications.