Project: South Farmingdale Iron Removal
Client: South Farmingdale Water District
Size: 2 MGD
Services provided: Water resources engineering, preparation of design documents, construction administration & inspection, project certification (NCDOH)
Greensand lends a hand
South Farmingdale Water District was ready for an upgrade to its iron removal system. The existing system had been designed and constructed in 1998 and used a Ferrosand for filtering. Experiencing reduced back wash run times and iron clogging, the District chose H2M for the upgrade of the filter media.
H2M specified a manganese greensand for the new filter media. Greensand is an organic clay mineral product that is bluish-green in color. As water is passed through the greensand material, soluble iron is oxidized from the solution and becomes a solid particle. The solid iron oxide is then trapped in the greensand filter.
Updating the filter media to this material allowed the District to switch from using potassium permanganate for regeneration of the greensand to using only chlorine; chlorine being both cheaper and easier to use and store than potassium permanganate. A second benefit was the durability of the greensand, which allowed for less frequent backwashes and a lower percentage of waste.
Reusing the two 8-foot diameter, 23-foot long horizontal pressure vessels for the iron removal system, the upgrade included updated controls and chemical treatment safety panels. The project met its goals for both time and budget.