Drinking Water TreatmentDrinking Water Treatment

Drinking Water Quality Drinking Water Quality

• USEPA Drinking Water Regulations USEPA Drinking Water Regulations • Coliform bacteriaColiform bacteria• Turbidity Turbidity • Organic and inorganic chemicalsOrganic and inorganic chemicals• RadionuclidesRadionuclides

Greater Cincinnati Water Greater Cincinnati Water WorksWorks

Major Treatment Processes:

•Settling (coagulation, flocculation)

•Filtration

•Disinfection

Common Treatment StepsCommon Treatment Steps

• CoagulationCoagulation• FiltrationFiltration• disinfectiondisinfection

Coagulation Coagulation

• overcome negative charged overcome negative charged clays by adding alum (Al3+) or clays by adding alum (Al3+) or ferric (Fe 3+) ionsferric (Fe 3+) ions

FiltrationFiltration

• Rapid sandRapid sand

• Slow sand (surface cake also Slow sand (surface cake also bioactive)bioactive)

• Dual mediaDual media

• flotationflotation

DisinfectionDisinfection

• Chlorine, chloramine, chlorine Chlorine, chloramine, chlorine dioxidedioxide

• Ozone, UVOzone, UV

Other methodsOther methods

• Activated carbonActivated carbon• Ion exchange/chemical precipitationIon exchange/chemical precipitation• Membranes Membranes • Air strippingAir stripping

(then comes distribution)(then comes distribution)

Pur DemonstrationPur Demonstration

AlternativesAlternatives• DesalinationDesalination

• solar stillsolar still• Filters Filters

• Slow sand filterSlow sand filter• Dual bucket sand filterDual bucket sand filter• Diatomaceous earthDiatomaceous earth• Bag and cartridge filtersBag and cartridge filters

• ConservationConservation• RecyclingRecycling

Science Fair ProjectScience Fair Project

Design a water treatment deviceDesign a water treatment deviceFactors to consider:Factors to consider:• Technology (feasibility, reliability, Technology (feasibility, reliability,

quantity, quality)quantity, quality)• minimum parameters turbidity and total minimum parameters turbidity and total

coliform coliform • Environmental impacts (air emissions, Environmental impacts (air emissions,

waste management, energy use)waste management, energy use)• CostCost

Plastic housing provided the support for her fabric-based filtration device.

Their water purification system incorporated two buckets, filtration material, and a siphoning tube.

Secured funnels in series so that the dirty water would pass through a variety of filter material before being tested for its effluent quality.

The water cascaded downward through graded filter bed material, modeling a fixed bed water treatment scheme.

ResourcesResources• Solar Still Solar Still

• Laboratory Manual Laboratory Manual • Survival Still Survival Still

• Laboratory ManualLaboratory Manual• EPA : EPA :

http://www.epa.gov/safewater/kids/wsb/index.htmlhttp://www.epa.gov/safewater/kids/wsb/index.html• Water Works LessonWater Works Lesson• Carbon treatment lessonCarbon treatment lesson• Chlorination lesson Chlorination lesson

• Oasis water treatment websiteOasis water treatment website• American Water Works Association websiteAmerican Water Works Association website• Water Environment Federation websiteWater Environment Federation website• handoutshandouts