Recent Advances in UV TechnologyBy

Dr. G. Elliott Whitby

Suntec environmental

106 Rayette Road, Unit #1

Concord, Ontario, Canada L4K 2G3

November 15, 2002

PRESENTATION OUTLINEPRESENTATION OUTLINE

LATEST ADVANCES

1. UV Lamps

2. Cleaning Systems

3. Need for the Bioassay

DIFFERENT LAMP TYPESDIFFERENT LAMP TYPES

1. Low-Pressure Low Output

2. Low-Pressure High Output

3. Medium Pressure

4. Pulsed Power

HIGHER OUTPUT LOW PRESSURE LAMPSHIGHER OUTPUT LOW PRESSURE LAMPS

OPERATION OF A LOW-PRESSURE MERCURY LAMP

Cathode Anode

Quartz Tube

UV Light

Germicidal lamps operate electrically on the same principle as fluorescent lamps.

EFFECT OF TEMPERATURE ON LAMP OUTPUTEFFECT OF TEMPERATURE ON LAMP OUTPUT

Optimum

EFFECT OF INCREASING LAMP CURRENT G64T5LEFFECT OF INCREASING LAMP CURRENT G64T5L

11.21.41.61.8

22.22.4

0 5 10 15 20 25 30 35

Temperature C

UV

Inte

nsity

mW

/cm2 G64T5L 525 mA

G64T5L 425 mA

37.5 % Increase in UV Light

The Effect of Water Temperature on the Output of theThe Effect of Water Temperature on the Output of the SuntecSuntec environmentalenvironmentalGXO74T5LS High Output and the G64T5L Low Output LampGXO74T5LS High Output and the G64T5L Low Output Lamp

1.00

2.00

3.00

4.00

5 10 15 20 25 30

Water Temperature oC

UV

Out

put

mW

/cm

2

GXO74T5LS

G64T5L

SUNTEC 500 WATT AMALGAM LAMPSUNTEC 500 WATT AMALGAM LAMP

LOW PRESSURE MERCURY AMALGAM LAMPLOW PRESSURE MERCURY AMALGAM LAMP

EFFECT OF THE AMALGAM IN AIREFFECT OF THE AMALGAM IN AIR

A.G. Jack IEE Proc. Vol. 127Pt. A. No. 3, April 1980

EFFECT OF WATER TEMPERATURE ON EFFECT OF WATER TEMPERATURE ON THE 500 WATT AMALGAM LAMPTHE 500 WATT AMALGAM LAMP

R2 = 0.0158

7

7.5

8

8.5

9

9.5

0 5 10 15 20 25 30 35

Water Temperature °C

UV

Flu

ence

Rat

e m

W/c

m2

COMPARISON OF G64T5L, LPX200 AND LPX500COMPARISON OF G64T5L, LPX200 AND LPX500

11.5

22.5

33.5

44.5

5

0 50 100 150 200 250 300

Flow in USGPM per Lamp

Log

N/N

o

LPX500G64T5L

LPX200

Fecal Coliforms

LONGER LAMP LIFELONGER LAMP LIFE

EFFECT OF LAMP AGE ON THE UV OUTPUT OF EFFECT OF LAMP AGE ON THE UV OUTPUT OF THE G64T5LTHE G64T5L

Noesen et al., WEFTEC 1999

EFFECT OF COATING ON THE UV LAMP OUTPUT EFFECT OF COATING ON THE UV LAMP OUTPUT OF THE G64T5LOF THE G64T5L

Giller, Disinfection 2000

OUTPUT OF THE LPX200 LAMP WITH TIMEOUTPUT OF THE LPX200 LAMP WITH TIME

60

70

80

90

100

110

0 2000 4000 6000 8000 10000 12000

HoursPerc

ent O

utpu

t Aft

er 1

00 H

ours

MEDIUM PRESSURE LAMPSMEDIUM PRESSURE LAMPSHIGHER UV OUTPUTHIGHER UV OUTPUTLONGER LAMP LIFELONGER LAMP LIFE

CONSTRUCTION OF THE MEDIUM PRESSURE CONSTRUCTION OF THE MEDIUM PRESSURE MERCURY LAMPMERCURY LAMP

EFFECT OF LAMP DIAMETEREFFECT OF LAMP DIAMETER

Giller, IUVA Singapore Oct Nov 2002

EFFECT OF PINCH COATINGEFFECT OF PINCH COATING

Giller, IUVA Singapore Oct Nov 2002

EFFECT OF HALOGENS ON LAMP LIFEEFFECT OF HALOGENS ON LAMP LIFE

Giller, IUVA Singapore Oct Nov 2002

COMPARISON OF A LOW AND MEDIUM COMPARISON OF A LOW AND MEDIUM PRESSURE MERCURY LAMPSPRESSURE MERCURY LAMPS

STUDY BY GRAY & OSBORNE ON POWER USE BY UVSTUDY BY GRAY & OSBORNE ON POWER USE BY UVWEFTEC, 2000 ANAHEIM, CAWEFTEC, 2000 ANAHEIM, CA

IMPROVED CLEANING SYSTEMSIMPROVED CLEANING SYSTEMS

CLEANING SYSTEMS BRIEF HISTORYCLEANING SYSTEMS BRIEF HISTORY

LPX200/500 ULTRAVIOLET DISINFECTION SYSTEMLPX200/500 ULTRAVIOLET DISINFECTION SYSTEM•A non-chemical method of cleaning the quartz sleeves•Fully programmable cleaning cycle•Scrapers are easily replaced•Electrically driven, no air or hydraulic fluids•Free floating scrapers follow the contours and alignment of the quartz sleeves

LPX200/500 Ultraviolet Disinfection SystemLPX200/500 Ultraviolet Disinfection System

Control UV System

LPX200/500 Ultraviolet Disinfection SystemsLPX200/500 Ultraviolet Disinfection Systems

UV System with Added Iron

LPX200 FLOW PER LAMP VERSUS FECAL LPX200 FLOW PER LAMP VERSUS FECAL COLIFORMSCOLIFORMS

1

10

100

1000

10000

0 50 100 150 200 250 300 350

Flow in Litres per Minute per Lamp

Feca

l Col

iform

s pe

r 10

0 m

L

Typical Limit for Fecal Coliforms

Wastewater CharacteristicsFecal Coliforms per 100 mL 73,000Total Suspended Solids < 5.0 mg/LPercent Transmission at 254 nm 68 %

EFFECT OF IRON ON THE FECAL COLIFORMS EFFECT OF IRON ON THE FECAL COLIFORMS AFTER UV DISINFECTIONAFTER UV DISINFECTION

2

2.5

3

3.5

4

4.5

0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400

Hours

Added IronNo Iron

Log

N/N

o of

the

Feca

l Col

iform

s

THE NEED TO HAVE A METHOD FOR THE NEED TO HAVE A METHOD FOR COMPARING DIFFERENT UV SYSTEMSCOMPARING DIFFERENT UV SYSTEMS

A STANDARD BIOASSAYA STANDARD BIOASSAY

WHY PERFORM A BIOASSAYWHY PERFORM A BIOASSAY• With the introduction of electronic ballasts and proprietary lamps all the UV

systems are different.

• Allows the comparison of low and medium pressure UV lamps.

• A standardized bioassay allows the direct comparison of different UV systems and this allows the consultant to tell each manufacturer how many lamps they must use to deliver a specific UV fluence.

• Under the proper conditions a bioassay insures that the UV fluence or UV dose claimed by the manufacturer is actually delivered by the UV equipment.

• A bioassay confirms the UV output of the UV lamps under actual operating conditions as versus measurements in air.

• A bioassay eliminates any disagreements that may take place over how to calculate the UV fluence within a reactor.

LAMP AND BALLAST COMPARISONLAMP AND BALLAST COMPARISON

45 %40 %57 %32 %41 %Efficiency excluding the ballast

42 %38 %52 %30 %37.7 %Efficiency including the Ballast

106125 W139.9 W65 to 70 W32 WUVC Watts

1.6 to 2.0 A3.3 A3.3 A1.1 A0.525 ALamp Current (A)

235310 W247.2 W210 W78 WPower to the Lamp

ElectronicElectronicElectronicElectronicElectronicBallast

250 W330 W271.5 W225 W85 WPower to the lamp and Ballast

Company CPublications etc

Company BLiterature etc

Company BTest Report

Company AG64T5LParameters

Factors Affecting UV PerformanceFactors Affecting UV Performance

UV Transmission*

Suspended Solids

Hydraulics* (Retention Time, Turbulence)

Iron, Hardness, Dissolved Solids*

Wastewater Source*

Disinfection Requirement* (UV Fluence)

Lamp Output* (New, End of Life, % Germicidal Light)

*Tested by a Bioassay

What is a Bioassay?What is a Bioassay?

It is a microbiological method of determining the delivery of UV light by a UV system under specific conditions of the UV unit and the water.

How is a Bioassay Performed?How is a Bioassay Performed?Basic Steps in a Bioassay

1 Select a microorganism that is UV resistant, not pathogenic and easy to grow or is already present in the effluent

2 Irradiate the microorganisms with exact UV fluences to create a calibration curve of UV fluence versus log kill

3 Set-up an UV system to simulate worst case conditions of the lamps and water

4 Put the calibrated microorganisms through the UV unit at different flow rates and measure the numbers in the influent and effluent to get the log kill

5 Using the calibration curve create a curve of flow per lamp versus UVfluence

6 Create a report describing the exact test conditions

BIOASSAY ON A UV SYSTEM WITH TWO BIOASSAY ON A UV SYSTEM WITH TWO LAMP CURRENTSLAMP CURRENTS

0

1

2

3

4

5

6

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180

Flow in Litre per Minute per Lamp

425 ma QS 23 by 20 mm525 ma QS 23 by 20 mm

Log

Kill

of M

S2 C

olip

hage

Flow Through Test ResultsFlow Through Test Results

0

10

20

30

40

50

60

70

80

50 100 150 200 250 300 350

Flow in Litres per Minute per Lamp

Flue

nce

mJ/

cm2

LPX200 Full Power

LPX200 60 % Power

G64T5L 525 mA 7.62cm Spacing

Standard Test ProtocolsStandard Test ProtocolsNWRI/AWWARF UV Guidelines

Drinking water

Water reuse

ETV/EPA/NSF Program

Stormwater

Secondary Effluent

German and Austrian Standards

Drinking water

SUNTEC SUNTEC environmentalenvironmentalWORLD LEADERS AND INNOVATORS OF UV TECHNOLOGY