Potential Impacts of Untreated WastewaterC, N, P, pathogens

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Potential Impacts of Untreated Wastewater-C, N,
P, pathogens

• Oxygen Depletion
• Fish kills
• Eutrophication
• Either N- or P-limited

P fertilization experiment
umanitoba.ca
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Measuring Organic Compounds
Biochemical Oxygen Demand (BOD)
Essential NutrientsSeed Microbes
D1
Wastewater Sample
DO
D2
Time
Organic waste
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Early History of Wastewater
Cloaca Maxima-the main sewer of ancient
Rome,Built 6th century BC(Ettore Roesler Franz)

• Prior to 1900, dilution the solution

Construction of sewage collection system in Rhode
Island, 1800s
www.cet.nau.edu
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Suspended Growth Systems
Plug Flow or CMAeration Tank
SecondaryClarifier
PrimaryClarifier
Influent
Effluent
Return Activated Sludge
Sludge
Sludge
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Microbiology of Activated Sludge
Heterotrophic Bacteria -Achromobacter
-Alcaligenes -Arthrobacter -Citromonas
-Flavobacterium -Pseudomonas -Zoogloea
Autotrophic Bacteria -Nitrobacter
-Nitrosomonas
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Air Requirement
Open or Perforated PipeCity of Livermore
Membrane or Ceramic Disk Diffusersnccsupplies.com

SurfaceAeratorwww.kamps.be
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Attached Growth Systems
carroll1.cc.edu
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Mass Transfer in Biofilms
Stagnantwaterlayer
D.O.
S, O2
CO2
Air
SupportMedia
Biofilm
Water Wave
10 mm
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Support Media

• Crushed Durable Stone
• Limestone
• Granite
• Rock
• Slag
• Plastic Media

Virtually all new trickling filters are
constructed with plastic packing --Metcalf and
Eddy
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Air Requirement
Open or Perforated PipeCity of Livermore
Membrane or Ceramic Disk Diffusersnccsupplies.com

SurfaceAeratorwww.kamps.be
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Anaerobic Process Description
Gas Out
Gas storage
Scum Out
Scum
SupernatantOut
Supernatant
Raw SludgeIn
Active digestion
Digested sludge
DigestedSludge Out