GreensandPlus™ Filter For The Removal Of Iron, Manganese, And Arsenic

The Hungerford & Terry underdrain system performs the dual function of backwash water distribution and filtered water collection and is the most critical aspect of a filter design. Hungerford & Terry can provide a number of different underdrain designs to meet this criteria based on either the engineer's or customer's specific requirements.

The optimum underdrain system is the headerlateral underdrain utilizing the time-proven H & T sand valve. For over 70 years, this nonclogging, noncorroding distributor has proven itself vastly superior to all others. Constructed of stainless steel with a Delrin1 shank and Monel¹ splines, this distributor will provide years of trouble-free service without the problems inherent in some competitors' distributors.

In addition to the H & T sand valve underdrain, a nonferrous hub-radial lateral underdrain or header-lateral underdrain with drilled orifices may be provided.

Although some equipment suppliers feature well screen-type strainers, our many years of experience make us reluctant to offer such a design. We have found that such strainer-type distributors may eventually become obstructed.

This results in disruption of the media bed, poor backwash distribution, and channeling – all requiring premature filter restoration.

With many years of experience in the design and manufacture of filter systems, H&T can provide the precise underdrain configuration required for optimum distribution with minimal head loss.

¹ Monel is a registered trademark of International Nickel Co.