Post on 13-Jan-2016
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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