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1/23/2019
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NUTRIENTS AND NUTRIENT ANALYSIS IN
WASTEWATER TREATMENT
BNR Lab Testing Parameters
Nitrogen
TNT 826 Total NEffluent Monitoring 826
TNT 880 Simplified TKN 880.pdfEffluent Monitoring
Customer approval required per region
DRB200
BNR LAB TESTING PARAMETERS
NitrogenTNT831 Ammonia 831.pdf
Influent, Effluent, and Process verificationTNT835 Nitrate 835
• The term “nutrients” in the context of wastewater treatment describes a group of organic and inorganic nitrogen- and phosphorous-containing compounds
NITROGEN• Present in fertilizers• Major contributor to nutrient pollution • Nitrogen gas (N2) makes up about 80% of our atmosphere• Can take on different forms in WW process
PHOSPHOROUS• Present in fertilizers and detergents• Major contributor to nutrient pollution • Orthophosphate (PO4
-3) = Reactive Phosphorous • Can be present in different forms in WW process
FORMS OF PHOSPHOROUS• Polyphosphates/ Pyrophosphates • Orthophosphate ion (PO4
-3) • Orthophosphate may take the form of H2PO4
- and HPO4-2 ,
depending on pH• Can occur in different forms in WW process
Pyrophosphate
Adenosine Triphosphate
(ATP)
Phosphoric acidSodium Hexametaphosphate
WHY NUTRIENTS MATTER • Why nutrients matter
– Nutrients in wastewater effluent can accumulate at the outfall of a wastewater treatment facility and create conditions that are detrimental to both humans and the environment.
• Environmental Effects– Eutrophication - A process where
increased nutrient levels promote excessive growth of algae and certain types of bacteria.
– Hypoxia – A result of eutrophication. When large colonies of algae die, and accumulate at the bottom of a river or lake, their subsequent decomposition and decay causes the aquatic environment to become oxygen-depleted. Hypoxia can be fatal to fish, crustaceans, and any other aquatic organisms that require oxygen to survive.
WHY NUTRIENTS MATTER• The USEPA has identified nutrient pollution
as a significant problem
• The National Pollutant Discharge Elimination System (NPDES) grants permits to wastewater treatment plants (WWTPs) that discharge their treated water back into the environment
• Any WWTPs that discharges to the environment have maximum nitrogen and/or phosphorous levels on their effluent permits
• If maximum levels are exceeded, the treatment facility can incur fines until the problem is corrected
WHY NUTRIENTS MATTER• In addition to the environmental impacts
that nutrients pose, wastewater plants are also interested in quantifying various nutrient levels to make their treatment processes more efficient, which can ultimately save them time and money
• Under anaerobic conditions, phosphate accumulating organisms (PAOs) consume organics (volatile fatty acids, VFAs) and release phosphate
• Under aerobic conditions, phosphate accumulating organisms take up all phosphate released during anaerobic phase, as well as any other phosphate in solution
consume all the phosphate released in the anaerobic phase, as well as any other phosphate in solution (luxury uptake). Then phosphate-loaded bacteria are removed through the sludge wasting process, resulting in phosphorous removal
PHOSPHOROUS
phosphate (PO4-3)
from anaerobic stage
Aerobic Conditions
+ more phosphate
in solution
O2
O2
O2
O2
O2
O2
PAO
PAOPAO
O2
O2
BIOLOGICAL P REMOVAL
ANAEROBICNo DO, No Nitrate
AEROBICDO > 0.5mg/L
Poly-P
PHA
Glycogen
EMP
CO2
NADH
VFA
Ac-COA
Energy
PO4
PO4 PO4
Poly-P
PHA
Glycogen
CO2 + H2O
O2
PO4
PO4
You can’t control bacteriaYou can only control their environment
** Effluent Permit Limits are in Total Phosphorous (TP)
•Where•Plant Influent
•Why•Monitor phosphorous load before it gets to phosphorous removal system
•What
•PHOSPHAXsc Phosphate Analyzer with Filter Probe sc
PHOSPHOROUS
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PHOSPHAX SC ANALYTICAL SECTION
(1) 2-beam-LED-photometer with colorimetric method (yellow), two ranges
(2) Air pump to move liquids
(3) Dosing pump for reagent
(4) Cleaning solution
(5) Reagent
Range: 0.05 to 50mg/L PO4-P
1
2
54
3
•Where•Phosphorous Removal System
•Why•Monitor or control chemical addition/efficiency of removal system
•Monitor Biological Phosphorus Removal system
•What
•PHOSPHAXsc Phosphate Analyzer with Filtration
PHOSPHOROUS
Real Time Phosphorus Chemical Feed Control.Optimize Chemical Dosing
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•Where•Plant Effluent
•Why•Monitor for upsets in the plant
•Compliance with regulations
•What
•PHOSPHAXsc Phosphate Analyzer with Filtration
PHOSPHOROUS
NUTRIENT REMOVAL PARAMETERS
• pH and Alkalinity- pH can be depressed by Nitrification.
7.14 lb. of alkalinity consumed per lb. of NH₃ oxidized.
• ORP/Oxidation Reduction Potential
Dissolved Oxygen is difficult to measure accurately in both an Anoxic and Anaerobic environment.
• And of Course the all important DO measurement in an Aerobic environment for Nitrification and Luxury uptake of Phosphorus or consider Ammonia based aeration
with RTC LDO2
BIOLOGICAL NUTRIENT REMOVAL BASICS
Anaerobic ZonePAO release huge amounts of P to access VFA.
Anoxic ZoneHeterotrophic Facultative Bacteria respirate using the oxygen attached to Nitrate.
Aerobic ZoneConversion of Ammonia through nitrification.Organisms take up to ten times their body weight in Phosphorus in a processcalled “Luxury Uptake”.
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BNR TREATMENT SCHEMES
DO between 2.0 and 4.0 mg/L or RTC with Ammonia based Aeration
Three Stage Phoredox A²/O
AnaerobicP release
Anoxicdenitrification
AerobicNitrification and Luxury uptakeDO 0.0 mg/l
ORP < -150 mvDO < .5 mg/LORP between -150 and + 150 mv
BNR TREATMENT SCHEMESUNIVERSITY OF CAPETOWN AND VIRGINIA INITIATIVE PROCESSES
DO between 2.0 and 4.0
mg/L or RTC withAmmonia based Aeration
AnaerobicP release
Anoxicdenitrification
AerobicNitrification and Luxury uptakeDO 0.0 mg/l
ORP < -150 mvDO < .5 mg/LORP between -150 and + 150 mv
RAS
Denitrified MLSS
BNR TREATMENT SCHEMESFIVE-STAGE BARDENPHO PROCESS
DO between 2.0 and 4.0 mg/L or RTC withAmmonia based Aeration