KDF Process Media are highpuritycopper-zinc granules thatreduce contaminants in waterusing oxidation/reduction(redox) reaction. KDF 55process medium is an effectivechlorine removal agentused in point-of-entry (POE) treatmentof municipal water supplies. KDF 85process medium is an effective iron(ferrous) and hydrogen sulfide (H2S)removal agent that may be used alone orto protect existing water filtration/purification technologies in POEtreatment of groundwater supplies.These unique, innovative and environmentallyresponsible media consist of highpurity copper-zinc granules that use redox(the exchange of electrons) in patentedKDF 55 and 85 Process Media in Point-of-EntryWater Treatment Systems Chlorine, Iron andHydrogen Sulfide Reductionproducts to effectively reduce/removechlorine, iron, hydrogen sulfide, heavymetals, and control microorganisms inpotable water without the use of chemicals.Whats more, KDF 55 and 85 media arehighly efficient and tank size requirementsare modest for more economical systemengineering and installation.This bulletin describes the proper use ofKDF media in residential (whole house),commercial, institutional, and light industrialbuildings and facilities with potablewater service flows in a range from 3 to324 gallons per minute with maximumchlorine, iron, and H2S concentrationsof 5 ppm/mgl.Medium Requirementsand System SizingEasily the most critical aspect of pressurefilter performance is the relationship offlow rate to surface of KDF media. Inaccuratesizing is the most common reason fortrouble in filter systems. The nominal flowrate in the service cycle depends on surfacearea available. For most types of filtermedia, the service flow rate must notexceed five gallons per minute (gpm) persquare foot of surface area, with at least a30-inch filter bed depth.Service flow rates with KDF ProcessMedia, however, may be calculatedat 15 gpm per square foot of surfacearea (0.104 gpm per square inch).This is three times the effective flowrate of other filter media.
In electrochemical reductionprocesses, surface products areformed when KDF media areused in point-of-entry (POE)water treatment systems. Thesebyproducts, along with any calcium andmagnesium precipitate, must be periodicallybackwashed. For backwash rates of 3 to 25gpm, use a high quality 3-cycle backwashvalve (service, backwash, purge). One with ahigh-flow backwash mode is best. For 36 to324 gpm, use a diaphragm nest valve.Remember to remove any backwash flowrestrictors. Select a distributor based onbackwash flow rate. For 3 to 11 gpm, use afine slotted distributor and for 15 to 324 gpm,use a hub and lateral distributor (#8 garnetunderbedding is recommended). Time thebackwash cycle for ten minutes and purge forthree minutes. Backwash at least three timesper week, more frequently if necessary,depending upon the quality of the watersupply. If more backwashing is required,repeat the entire cycle. Backwash flow ratesare a function of backwash water temperature;type, size and density of media; and thespecific design of the pressure filter. KDFProcess Media have a density of 171 poundsper cubic foot, which makes it a very highdensity medium requiring a backwash flowrate of twice the service flow.KDF media require 30 gallons per minute persquare foot of bed surface area. Very cold waterrequires somewhat lower backwash rates andwarmer water requires higher rates. Do notrestrict pipe size to the drain.Note: If backwashing procedures are not properlyfollowed, KDF Process Media may becomefouled. For proper cleaning techniques, contactKDF s Technical Department.