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Drinking Water Defenders A look into a drinking water treatment plant
Drinking Water Defenders A look into a drinkingwater treatment plant
Defending Against What?
How Do We Defend?
Watershed Protection
Water TreatmentCoagulation Flocculation SedimentationFiltration Reverse Osmosis Ion Exchange
Ozone Packed Tower Aeration UV Radiation Disinfection Corrosion Control
And the list goes on!
Defending Against VOCs, Perchlorate, NDMA and 1,4‐Dioxane!
Packed Tower Aeration (Air Stripping)Granular Activated Carbon (GAC)Ion Exchange OxidationUV RadiationDisinfectionCorrosion Control
Treatment Plant EssentialsChemical Feed EquipmentChemical Storage FacilitiesComputerized Control Systems (SCADA) PowerPumping SystemsTreatment EquipmentInstrumentation Treatment Plant OperatorsEngineering and Admin Support Safety and Security Systems
Treatment Plant ControlsElectronic instrumentation and computerized control systems are essential tools in operating a treatment plant
Supervisory Control andData Acquisition (SCADA)
Certified Treatment PlantOperators are the onlypersonnel permitted to work at and operate the Plant!
Drinking Water Well
VOC Removal by Packed Tower Aeration (Air Stripping)
Air Stripping Tower
Ion Exchange Treatment
Ion Exchange Resins
Fe/Mn Uranium
Perchlorate
Nitrate
Heavy Metals
Chromium
Arsenic
Bromide Bromate
TOC’s Softening
Perchlorate Selective Ion Exchange Resin
Regenerable Single Pass
Ion Exchange Systems
Contaminant
Contaminant
Ion Exchange Process
UV Treatment System
UV Treatment System
NDMA TREATMENT Photolysis ‐ the chemical decomposition of materials under the influence of light.
The NDMA absorbs the UV energy, which breaks the N‐N bond.
Process byproduct of concern is nitrite. The yield of nitrite is well below the CDPH drinking water standard for nitrite (1 mg/L as N). Chemical bonds are
broken by UV light
Ultraviolet Light (UV) Irradiation
1,4‐Dioxane Treatment
Photochemical process that breaks down organic constituents in water by the process of oxidation.
The UV‐oxidation reaction is initiated by the photolysis of hydrogen peroxide. When UV photons are absorbed by hydrogen peroxide dissolved in water, hydroxyl radicals are formed.
Hydroxyl radicals are highly reactive chemical species that then attack the contaminant molecule, breaking it into its component forms.
Advanced oxidation processes, which use peroxide and UV‐light
Disinfection and Corrosion ControlDisinfection‐ Injection of sodium hypochlorite to defend against microbiological contaminants in the water distribution system.
Corrosion Control‐ Injection of sodium hydroxide to adjust the pH of the water and the addition of ortho‐polyphosphate to inhibit corrosion of distribution piping.
Water Quality Monitoring
Track changes to contaminant levels in raw water.
Ensure effectiveness of treatment.
Maintain compliance with CDPH permit provisions.
Defending Drinking Water Takes A Team EffortScientific ResearchDrinking Water RegulationRegulatorsWater PurveyorsEngineersContractorsVendorsSuppliersOperators
This not This?
