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2019 Englewood PWO
PERACETIC ACID DISINFECTIONThe Good, the Bad, and the Slimy
Nikki Stephens
SafetyMomentAGENDA
1. PAA
2. The Good and Bad and Slimy
3. The Future
Property ValueColor Clear, colorless
Odor Vinegar, pungent
pH <1
Ev 1.81 V
Freezing Point <-20 °F
Specific Gravity 1.14 g/mL
Disinfectant EV (volts)
-OH 2.80
Ozone 2.07
Peracetic acid 1.81
Chlorine dioxide 1.57
Sodium hypochlorite 1.36
PERACETIC ACIDPAA, peroxyacetic acid, Ethaneperoxoic acid
PAA• Colorless, Vinegar Odor, Non flammable, and Soluble• pH: <1 (1:10 dilution), SG 1.135 g/ml (9.58 lbs/gal) • Flash point >207°F, Freeze Point <-20°F
Physical data
• Reactive with bases, metals, reducing agents, and combustible materials.Reactivity data
• Corrosive to soft metals, wood, nylon, common paint, cotton, leather, rubberCorrosivity data
• Stable up to 1 year under normal conditionsThermal and
chemical stability data
• Reacts violently with incompatible materials and high heat, produces Oxygen gas and steam during rapid decomposition.
Hazardous effects of contamination
SafetyMoment
PAA catalytically decomposes when contaminated. The reaction is exothermic.
https://envirotech.com/
CAPITALO&M
• Easy retrofit• Low freezing point• Less wear and tear• Less chemical
• No ammonia• No quenching?
• Long shelf life, stable• Shorter contact times
Reduce DBPs
Lower Toxicity
•Strong oxidizer
No nitrite lock
Reduces TSS
Increases DO
PAA Drivers
Proxitane® WW-12 VigorOx® WWT II BioSideTM HS 15% Peraclean®15 Peragreen®
22WW
EPA Registration (date of registration)
68660-1 (2013)
65402-3 (2008)
63838-2 (2015)
54289-4(2015)
63838-20 (2015)
Application Rateand Allowable Residual
0.5 – 10 mg/L<1.0 mg/L
0.5 – 15 ppm<1.0 mg/L, if DF>12, 0.09*DF
0.5 – 10 mg/L<1.0 mg/L
0.5 – 15 ppm<1.0 mg/L
0.5 – 10 mg/L<1.0 mg/L
Peracetic Acid (CH3COOOH) 12% 15% 15% 15% 22%
EPA registration ≠ “permitability”
State Allowable PAA Residual (ppm)
Alabama 1 mg/L
Arkansas Up to 2 mg/L in trials
California Allowing trials for underperforming UV systems
Colorado 0.4 mg/L (30-d ave) at DF=0; >0.7 mg/L daily max
Florida 1 mg/L, but require a minimum dose of 2 mg/L
Georgia 1 mg/L (trials)
Illinois Initially 1 mg/L for trials, but has since been rescinded
Iowa 0.7 mg/L
Kentucky Per engineer recommendation, generally 1 mg/L
Missouri 1 mg/L as a daily max, 0.7 mg/L as a monthly ave
New Jersey 1 mg/L for trials (under review)
Ohio 0.33 mg/L (Steubenville, OH)
Oklahoma 1 mg/L (Guidance published August 2017)
Oregon 1 mg/L, requiring monitoring of enteric viruses
Tennessee 0.4 mg/L for low DF; site specific for high DF, up to 2 mg/L has been permitted
Texas Anticipate EPA label (1 mg/L); GCWDA did not reopen permit
Washington Anticipate EPA label (pilot testing being conducted with 1 mg/L)
BALLAST WATER 0.5 mg/L as PAA per USCG 33 CFR Part 151
The Good and The Bad
CAPEX
• Retrofit• Less contact
time• Tanks and
pumps• Vendor
packages• Outdoor storage• Stable• Longer
equipment life
• 316 SS/ compatible materials
• Planning for decomp reactions
• Odor
Operations & Maintenance
• Less chemicals
• Less chemical• Smaller
system• Long shelf life• Less leaks• Low energy
• Few suppliers• High unit cost• Nuisance slime• Decomp risk• Adds cBOD• Lowers pH
The Non-$ Factors Performance/reliability Permitability No Cl DBPs Lower Toxicity No lasting residual No nitrite lock Reduce TSS Increase DO Emerging contaminants UV Synergy/ AOP potential Viruses Benefits to downstream users GHG reduction from less truck hauling
1
10
100
1,000
0 10 20 30 40 50 60 70 80 90 100
E. c
oli (
MPN
/100
mL)
Contact Time
E. coli vs. Contact Time
1 ppm PAA, 7/18
1 ppm PAA, 7/23
1ppm PAA, 7/26
1ppm PAA, 7/31
1.5ppm PAA, 7/25
1.5 ppm PAA, 7/19
The Slimy
The Slimy
Vince Chui
Residual Measurement
The Future
Control StrategiesEvery drop counts
Straight Flow-Paced Qeff, PAA Dose SP
Straight Flow-Paced with Residual Trim Qeff, PAA Dose SP, PAAFinal
Integrated CT* Qeff, CT SP, PAAInitial
Integrated CT* with Residual Trim Qeff, CT SP, PAAInitial, PAAFinal
Residual SP Residual SP, PAAInitial AND/OR PAAFinal
Feed Forward Qeff, WQPre, PAAInitial OR E.coliInitial
Integrated CT
Manoli et al., Water Research 2019, 11, 0043-13554
C(t) = (C0 – D)e-kt
Feed Forward ControlFeed Forward Qeff, WQPre, PAAInitia lOR E.coliInitial
C(t) = (C0 – D)e-kt
D(WQpre) OR ln(N/No)(WQpre)
Like UVT for UV or ORP for Cl
COD
Color
TSS
UVT
SAC
Temp
Dunkin et al., Environ. Sci Technol. 2017, 51, 2972-2981.
PAA Efficacy for Virus Inactivation
WERF StudyNational
LIFT14T16 - Evaluating Peracetic Acid as a Disinfection Alternative in Wastewater Treatment
Task 1 – Literature Review
Task 2 – Survey
Task 3 – Regulatory Workshops
Task 4 – Demonstration Studies
Task 5 – Guidance Document
Proposed Path Forward WRF Regulator Workshops
Regulations
• Develop federal water quality criteria
• Develop state water quality criteria for PAA
• Challenges:
• Decomposition kinetics
• Lack of flow-through data
• More testing is needed
• Treat PAA like ozone or UV and use the WET test
PAA Design Guidance ManualWater Environment Federation
STAY TUNED….
THANKS