Terry KeepNE Ohio Summer Conference

Mansfield, OhioAugust 20, 2015

UV ADVANCED OXIDATION FOR THE TREATMENT OF ALGAE-RELATED TASTE AND ODOUR COMPOUNDS IN DRINKING

WATER

2

UV DISINFECTION FOR DRINKING WATER

• Ultraviolet light (UV) one component in the multiple barrier municipal drinking water treatment train

• Well established technology• An excellent option to achieve additional disinfection • UV’s ability to inactivate many microorganisms, especially

Cryptosporidium and Giardia, without forming DBPs drives growth

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GROWING APPLICATION OF UV ADVANCED OXIDATION

Indirect Potable Reuse (IPR) Wastewater treated to drinking water quality

Groundwater Remediation Plume containment, site cleanup

Drinking Water Contaminated groundwater or surface water sources, Taste & Odour treatmentTotal Flow Rate for Trojan Municipal UV-Oxidation

Projects in

2000: <40 MLD

2011: ~2.2 BLD

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WATER STRESS IN AN

INTERCONNECTED WATER SUPPLY

Sources of contaminants in our water supply: - Industrial discharge- Agricultural runoff- Chemical releases- Municipal Wastewater

InjectionWell

ExtractionWell

Nutrients increase in Algae Blooms Taste & Odour, Algal Toxins

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EXAMPLES OF MICROPOLLUTANTS

Nitrosamines (e.g. NDMA) Disinfection byproducts

Pesticides & Herbicides Metaldehyde, Atrazine, Isoproturon, others

Petroleum Additives Including MTBE

Pharmaceuticals & Personal Care Products Includes potential endocrine disruptors

Taste & Odour CompoundsSeasonal occurrences of MIB, geosmin and others

Algal ToxinsChronic and acute effects from cyanobacteria-derived toxins

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TASTE & ODOUR, ALGAL TOXINS

Seasonal algae blooms occur in surface watersDecaying algae blooms result in MIB, geosmin, algal toxins, other T&O compoundsEarthy/musty, fishy, swampy, grassy tastes & odours at low ppt concentrationsDifficult to remove with conventional technologiesT&O episodes compromise public confidence in the safety of the water

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TASTE AND ODOUR TREATMENT STRATEGIES

• Potassium Permanganate– Limited Effectiveness

• Powdered Activated Carbon– Messy PAC & Sludge Handling, no Performance Guarantee

• Granular Activated Carbon– Frequent & Expensive Change-outs, no Performance Guarantee

• Ozone– Complicated System & Carcinogenic by-product (Bromate)

• UV-Oxidation– Simple, Effective for T&O with Simultaneous Disinfection,

Guaranteed Performance for life of system

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UV / H2O2 FOR TASTE AND ODOUR TREATMENT

UV Advanced Oxidation: Using UV and Hydrogen Peroxide to destroy trace organic contaminants in water by:UV-Photolysis UV-Oxidation

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UV-PHOTOLYSIS

Chemical bonds arebroken by UV light

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UV-OXIDATIONHydrogen peroxide

Hydroxylradical

Chemical bonds arebroken by hydroxyl radicals

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CONTAMINANT DESTRUCTION BALANCE

0.0

1.0

2.0

3.0

4.0

5.0

6.0

NDMA Atrazine Geosmin Microcystin-LR

UV-

Phot

olys

is/U

V-O

xida

tion

Con

trib

utio

n to

Tot

al

Con

tam

inan

t Red

uctio

n (r

elat

ive

to N

DM

A) UV + H2O2

UV Photolysis

APPLICATION OF UV ADVANCED OXIDATION FOR TASTE & ODOUR /

ALGAL TOXIN TREATMENT

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DUAL-MODE OPERATION

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UV-OXIDATION A RANGE OF T&O COMPOUNDS

0.0%

10.0%

20.0%

30.0%

40.0%

50.0%

60.0%

70.0%

80.0%

90.0%

100.0%

geos

min

2-m

ethy

lisob

orne

ol(2

-MIB

)

dim

ethy

l tris

ulfid

e

cis,

4-h

epta

nal

trans

, tra

ns, 2

,4-

hept

adie

nal

cis-

3-he

xeny

lac

etat

e

Earthy Musty Swampy Fishy Rancid fish Grassy(sweet)

Perc

ent R

emov

al

Performance

Target

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COMPOUNDS GENERATED BY SOME CYANOBACTERIA

Geosmin

2-Methylisoborneol (MIB)GSM and MIB can be detected by sensitive individual down to 4 ng/L (ppt)

[Geosmin] have been measured > 3000 ng/L

Aesthetics: T&O cmpds

Cylindrospermopsin (CYN)

Microcystin-LR (MC-LR) [MC]~1800ug/L meas drng bloom

Public Health: Cyanotoxins

WHO set li

mit at 1

µg/L

USEPA ad

ded CNTX

to th

e CCL

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ALGAL TOXINS OXIDIZED MORE EASILY THAN MIB

SYSTEM SIZING

Contaminant Quantum Yield

Contaminant - Hydroxyl Radical Rate Constant

Contaminant Molar Absorption Coefficient

Hydrogen Peroxide Concentration

Water Absorbance (UVT)

Water Matrix Hydroxyl Radical Scavenging Capacity

Lamp Type

SIZING FACTORS FOR ECT SYSTEMS

UV-PHOTOLYSIS AND UV-OXIDATION KINETICS

Hydrogen peroxide

Hydroxylradical

The overall kinetic equation describing the photolytic and UV/H2O2 photo-oxidative reactions of a

micropollutant C is:

][][][(

2][][][

22

300

2000

300

2000

22

2222

SkOHkCkV

FFNCk

V

FFNCk

dtCd

SOHC

OHSOHCCSC

UV-Photolysis UV-Oxidation

Fraction of light absorbed by contaminant, scavengers, and peroxide (fxn of wavelength, dependent on absorbance)

Lamp Spectral Photon Flux

Reaction rates with hydroxyl radical for contaminant (C) and scavengers (S)

Quantum Yield of contaminant and peroxide

Where:22

,, OHSC FFF

0N

k

CASE STUDIES

Aqua PA’s Neshaminy WTP, PennsylvaniaHatch Mott MacDonald Presented at New Jersey, Ohio and Pennsylvania Annual AWWA Conferences 2010

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Researchers Evaluated the following Treatment Technologies:

•PAC

•GAC

•Ozone

•UV AOP

Aqua PA’s Neshaminy WTP, PennsylvaniaHatch Mott MacDonald Presented at New Jersey, Ohio and Pennsylvania Annual AWWA Conferences 2010

Design Conditions:• Flow rate: 57 MLD, average 40 MLD• Design UVT: 93%• Influent [GSM]: 100ppt• Target effluent [GSM]: 10ppt• 1.0-log GSM treatment at average flow, 0.7 log at peak flow

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Estimates were based on a PAC dose of 30 mg/l and a 90-day taste and odor period

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Analysis was based on 90 days of taste and odor operation with a discount factor of 4%. Costs include capital, construction, operation and maintenance (including dry solids removal for spent PAC). The PAC costs were based on $0.95 per pound and $215 per ton of dry solids removal and a dose of 30mg/L.

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Estimates were based on a PAC dose of 30 mg/l and a 90-day taste and odor period. UV-oxidation was also evaluated over the same 90 day taste and odour period.

UV Reactor Chamber

Cooling Water Inlet

Cooling Water Outlet

UV Reactor Chamber

Ballasts

UV Reactor Chamber

Flow Meter

UV Reactor Chamber

UV Reactor UV Reactor

Cooling Water Inlet

Chemical FeedHydrogen Peroxide Tank (50%)

Chemical FeedHydrogen Peroxide Metering Pumps

PATOKA LAKE, IN STUDYMalcolm Pirnie – Presented at the WQTC November 2008

Researchers Evaluated the following Treatment Technologies:

• UV- AOP (8 mg/L)• PAC (30 – 110 mg/L)• GAC (7&15 min EBCT)• Ozone (1.2 - 4.8 mg/L)

Design Conditions:• Flow rate: 15 MGD, average 10 MGD• Design UVT: 93%• Influent [MIB]: 300ppt• Target effluent [MIB]: 5ppt• 1.8-log MIB treatment

PATOKA LAKE, IN STUDYMalcolm Pirnie– Presented at the WQTC November 2008

PERFORMANCE TESTING

Test Description UV (% Power) H2O2

No Treatment NONE NONE

UV Alone 100 NONE

H2O2 Alone NONE 8 ppm

50% UV+H2O2 50 8 ppm

100% UV+H2O2 100 8 ppm

• Treatment Target = 1.5-Log MIB

PERFORMANCE TESTING - RESULTS

0

0.49

0.04

1.41

2.23

0

0.5

1

1.5

2

2.5

Log

Redu

ction

Treatment Target

UV SYSTEM – TWO TRAINS OF THREE REACTORS

PERFORMANCE TESTING - CONCLUSIONS

• Neither UV or H2O2 used independently had the capability of achieving the required treatment target of 1.5-log reduction of MIB

• Combination of UV and H2O2 showed near 1.5-Log removal of MIB when UV functioning at 50% output

• 100% UV output and same H2O2 dose showed over 2-log removal of MIB

• Chlorine quenching used to remove residual H2O2 successfully co-functions as a residual disinfectant

LORNE PARK WATER TREATMENT PLANTRegion of Peel, (Serving Mississauga/Brampton, Ontario, Canada

• Largest UV-oxidation installation for T&O treatment in the world

• Flow rate = 390 MLD

• Both UV-oxidation and ozone technologies were evaluated

• UV-oxidation was ultimately selected due to its:

− Smaller footprint

− Safety (no liquid oxygen required on site)

− No carbon to foul membrane

− Performance Guarantee

LORNE PARK WATER TREATMENT PLANTRegion of Peel, Serving Mississauga/Brampton, Ontario, Canada

• Operates in “disinfection-only” mode for most of the year when T&O events do not occur

– Significant energy savings

• Peroxide dosing can be turned on immediately when an event is detected

• GAC-quenching removes residual peroxide before entering distribution

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REGIONAL MUNICIPALITY OF WEST ELGIN, ON

Source water is Lake ErieFlow rate 14.4 MLDTreatment train: coagulation/settling membranes UV-oxidation final disinfectionAlgal blooms in late summer/early autumnPreviously used Powder Activated Carbon for T&O (membrane fouling)Designed for 1.3-log Geosmin and 1.0-log MIB, algal toxins

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REGIONAL MUNICIPALITY OF WEST ELGIN, ON

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PERFORMANCE RESULTS WEST ELGIN, ONTARIO (APRIL 2009)

PLANTS RECENTLY SELECTING UV-OXIDATION

• Franklin, TN – 4 MGD; 1 log MIB/1.3 log GSM• Patoka Lake, IN, USA – 20 MGD; 1.8-log MIB• Lorne Park, Ontario – 100 MGD; 1.3-log GSM/1.0-log MIB• Groesbeck, TX, USA – 2 MGD; 1.0-log GSM• Waxahachie, TX, USA – 14 MGD; 1.4-log GSM• Mansfield, TX, USA – 7.5 MGD; 1.0-log GSM• Neshaminy & Shenango PA, USA – 15 and 16 MGD, 1 log GSM• Lucerne, CA, USA – 1.0 MGD; 1.3-log GSM• Alliance Ohio, USA – 7 MGD; 1.5 log MIB• Otter Lake Water Commission, Illinois, USA – 1.5 log MIB 5 MGD• Wellborne, TX - 2 MGD; 1.1 log GSM/0.8 log MIB

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CONCLUSIONS• UV-Oxidation (UV + H2O2) is being implemented worldwide

• UV-Oxidation successfully destroys taste and odor compounds, algal toxins, other micro pollutants

• Performance Guarantee: Guaranteed Removal vs. competitive products

• On/Off technology (no event, no O&M)

• Disinfection design for UVDGM

• Barrier for PPCPs/future regulations

• Excellent option post membrane (no PAC needed)

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Brady Sessums ETEC

Cell 225-955-2160Work 225-295-1200

bsessums@etec-sales.com

QUESTIONS?

THANK YOUTerry Keep

Trojan Technologies(519) 457-3400

tkeep@trojanuv.com