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 ZEOLITE For WATER FILTRATION

 ZEOLITE For WATER FILTRATIONMarkets:Swimming Pool Filter Medium, Waste Water/Sewerage Treatment, Heavy MetalRemoval, Water Filters, Water Prefilter; Agricultural, Horticultural and Industrial DamWater flocculationNatural Zeolite can be used to filter and purify swimming pools, town water supplies,sewerage effluent, biological wetlands, industrial and mining waste-water andaquaculture ponds.Water filtration, apart from the removal of solids and colloids, increasingly demands theefficient removal contaminants including heavy metals and other toxic substances,bacteria and other parasites. Conventional sand filter systems do not remove allcontaminants and therefore alternative or additional systems are required so that the waterquality meets compliance regulations.The filtering abilities of Zeolites offer a versatile and environmentally friendly option tocapture most contaminants found in water systems. Natural Zeolites can perform thesefunctions due to their high ion exchange capacity, adsorption-desorption energies andability for modification. Zeolites have an open, regular crystalline framework thatgenerates an electric field that interacts, attracts and binds various cations and, aftermodification, anions.Zeolites have a particularly high selectivity for ammonium (NH 4+ ) and can reduce theammonium content in waste-water by up to 97%. NH 4+ has serious environmentalconsequences because of its toxicity to aquatic life, contribution to algal eutrophication,reduction in dissolved oxygen and detrimental effects on disinfection of water.Modifications such as charge change from (-) to (+) provides Zeolite with the flexibilityto absorb anions as well as cations and also some non-polar organics such as benzene,toluene and xylene.Zeolites can be charged with ‘antibiotic’ cations of Ag, Cu, Zn to provide antimicrobialproperties. Zeolite filterbeds can remove contaminants to purify air (Ammonia NH 3 , H 2 S,CO 2 , CO, SO 2 ).The hard, durable nature of Zeolites enables them to perform a range of filter functionsto produce improved water quality more efficiently than both the conventional slow orrapid sand filter systems. robust, insoluble Zeolites have improved attrition qualities andare adaptable to re-use through regeneration and recycling.Benefits of Zeolite/Silica Sand Beds Over Traditional Silica Sand SystemsConventional Slow Sand Filter Systems (Andrews, 1993)The top 20cm of a 1 metre thick bed of finely graded silica sand (0.5mm to 0.6mm) wasreplaced with Zeolite. The Benefits Are:  Higher throughput rate up to 0.75m 3 /hr/m 2 versus 0.15m 3 /hr/m 2 , while stillmaintaining water quality (measured in turbidity).  Longer runs, up to 50%, even at higher loadings.  Up to 3 to 5 times more water processed between maintenance scrapings.  Curing time is less, due to the rapid development of the schmutzdecke or biofilm.Conventional Rapid Sand FiltrationBurtica et al., 1997 found:  The optimum height of the Zeolite filtering layer is 35% of the height of quartz sand.  The effluent obtained with Zeolite was better than the results obtained with sandfilters.  Zeolite reduced turbidity and, organic charge (2nd filtering cycle) by 30% as opposedto 10% with sand.Sewerage/Waste-water TreatmentZeolite significantly improves the plant capacity, process efficiency and effluentdischarge quality from activated sludge sewerage treatment plants. It is also markedlyimproves nitrification and reduces odours to negligible levels. The Zeolite particles act asseeds to boost bacterial flocs by attracting and increasing bacterial action per unitvolume.Filtration Removal of Heavy MetalsZeolites are low cost ion-exchangers for the removal and recovery of heavy metalscations (Pb, Cu, Cd, Zn, Co, Cr, Mn and Fe; Pb, Cu as high as 97%) from drinking andwaste-waters.Zeolite rotary hoed (to a depth of 30cm – 40cm; 6.67 mg Zeolite/kg spoil) into a tailingsdump with high levels of Cu and Zn sulphide contamination reduced Cu and Zn levels inwaste-water discharge by 95% and 92% respectively.LinersZeolites can be used in lining seals around town garbage landfills, tailings dump/damsand low-level radioactive waste repositories to prevent groundwater contamination.Food IndustryFilter aid for purifying and clarifying (e.g. wine or sugar solutions).