GoodGood coolingcooling towertower practisespractises

Georges Hoeterickx Georges Hoeterickx Evapco Evapco EuropeEurope

GoodGood coolingcooling towertower practisespractises Design Design considerationsconsiderations

ApproachApproach

: : DifferenceDifference

betweenbetween

coolingcooling

towertower

outletoutlet

temp. temp.

and design entering and design entering wbwb

temp.temp.

Design Design considerationsconsiderations CoolingCooling towertower sizesize versus versus approachapproach

0

1

2

3

4

5

6

3 4 5 6 7 8 9 10 11 12

Coo

ling

Tow

er S

ize

Approach ° F

Design Design considerationsconsiderations Minimum Minimum approachapproach

CTI CTI CertificationCertification

underunder

STDSTD--201201CertificationCertification

is is limitedlimited

to to thermalthermal

operatingoperating

conditionsconditions…….. and a .. and a coolingcooling

approachapproach

of of 2.82.8°°C (5C (5°°F) F) oror

greatergreater……..

GoodGood coolingcooling towertower practisespractises CoolingCooling towertower rangerange

RangeRange

::DifferenceDifference

betweenbetween

coolingcooling

towertower

inletinlet

and and

coolingcooling

towertower

outletoutlet

temperaturetemperature. .

Design Design considerationsconsiderations CoolingCooling towertower sizesize versus range versus range

0

0,2

0,4

0,6

0,8

1

1,2

80% 90% 100% 110% 120% 130% 140% 150%

Range

C.T

. Siz

e

GoodGood coolingcooling towertower practisespractises Design Design considerationsconsiderations

AvoidAvoid

recirculationrecirculation

: : Bypass of warm discharge air Bypass of warm discharge air intointo

the the coolingcooling

towertower

air air inletinlet

willwill

causecause

capacitycapacity

losseslosses. .

Design Design considerationsconsiderations AvoidAvoid recirculationrecirculation

Top of Top of coolingcooling towertower shouldshould bebe at least level at least level withwith enclosureenclosure..

Design Design considerationsconsiderations AvoidAvoid recirculationrecirculation

Fan discharge Fan discharge velocityvelocity : min. 1200 : min. 1200 fpmfpm(6 m/sec).(6 m/sec).DownwardDownward velocityvelocity : max. 600 : max. 600 fpmfpm(3 m/sec).(3 m/sec).

Design Design considerationsconsiderations AvoidAvoid recirculationrecirculation

Limit Limit downwarddownward velocityvelocity -- twotwo sideside air air inletinlet unitsunits

Design Design considerationsconsiderations AvoidAvoid recirculationrecirculation

Limit Limit downwarddownward velocityvelocity -- single air single air inletinlet unitsunits

GoodGood coolingcooling towertower practisespractises Design Design considerationsconsiderations

UseUse

of of VFDVFD’’ss

forfor

fan motorsfan motors

: : AllowAllow

to to controlcontrol

air air flowflow

throughthrough

the the coolingcooling

towertower

Design Design considerationsconsiderations VFDVFD’’ss forfor fan motors fan motors

Energy Energy savingsaving

? ?

CondenserCondenser water temp 1water temp 1°°FFChillerChiller

efficiency 3%efficiency 3%

CoolingCooling towertower kW = ~ 5 %kW = ~ 5 %ChillerChiller

kW. kW.

Design Design considerationsconsiderations VFDVFD’’ss forfor fan motorsfan motors

Water Water consumptionconsumption : : Air Air flowflow

Water Water consumptionconsumption

PlumePlume formationformation ::Air Air flowflow

PlumePlume

formationformation

tendencytendency

NoiseNoise controlcontrol @ @ nightnightFan @ half speed : Fan @ half speed : ––

9 9 dBAdBA

fan fan noisenoise

(60% (60% capacitycapacity) )

Design Design considerationsconsiderations VFDVFD’’ss forfor fan motorsfan motors

Min. RPM Min. RPM forfor geargear(motor speed (motor speed ≥≥

450 RPM)450 RPM)

GearGear withwith mechanicalmechanical oiloil pump pump forfor proper proper lubricationlubrication

Design Design considerationsconsiderations CoolingCooling towertower basinsbasins

CommonCommon

basinbasin

+ + EasierEasier

basinbasin

and and coolingcooling

towertower

constructionconstruction..+ No + No needneed

forfor

equalizingequalizing

connectionconnection--

Maintenance Maintenance ––

sumpsump

cleaningcleaning

GoodGood coolingcooling towertower practisespractises Design Design considerationsconsiderations

CoolingCooling

TowerTower

BasinBasin

: : HoldHold

circulatingcirculating

water of the water of the towertower. .

Design Design considerationsconsiderations CoolingCooling TowerTower BasinBasin

IndividualIndividual

BasinBasin

per per CellCell

+ + EasierEasier

forfor

maintancemaintance

(water)(water)--

NeedNeed

equalizingequalizing

betweenbetween

basinsbasins..--

More More costlycostly

constructionconstruction

Design Design considerationsconsiderations CoolingCooling TowerTower BasinBasin

Sound mats to Sound mats to reducereduce

water water noisenoiseNoiseNoise reductionreduction functionfunctionnumbernumber of of layerslayersdistancedistance mats mats –– water in water in basinbasin !!

Sound mats Sound mats willwill obstructobstruct basinbasin accessaccess : : maintenancemaintenance !!

GoodGood coolingcooling towertower practisespractises

ObtainObtain

the the specifiedspecified

and correct and correct qualityquality

level !level !

ObtainObtain the the specifiedspecified qualityquality CostCost distribution distribution mainmain items items

Fan

Gear & Motor

Fill

Structure

Louvers

DE

Water Dis.

Fan Stack

Other

GoodGood coolingcooling towertower practisespractises ObtainObtain the the specifiedspecified qualityquality

TypicalTypical

requirementsrequirements: :

ObtainObtain the the specifiedspecified qualityquality FRP FRP structurestructure

ReputableReputable manufacturersmanufacturers have have theirtheircomponentscomponents thirdthird party party testedtested perperASTM E 84 ASTM E 84 forfor

strengthstrength

valuesvalues

and and

flamabilityflamability

AskAsk ifif these these evidencesevidences are part of contract are part of contract submittalssubmittals ! !

ObtainObtain the the specifiedspecified qualityquality FRP FRP structurestructure

ThreeThree

factors factors influenceinfluence

lifelife

expectancyexpectancy

::

CreepCreep : long term : long term deformationdeformation of a of a membermemberunderunder loadload

ShearShear : FRP : FRP strongstrong in in oneone directiondirection

UV UV degradationdegradation

ObtainObtain the the specifiedspecified qualityquality FRP FRP structurestructure : : creepcreep

Design Design structurestructure loadsloads primarilyprimarily taken taken bybyfiber fiber –– unidirectionalunidirectional

LoadsLoads byby resinresin to to bebe maintainedmaintained lowlow

Correct design Correct design assuresassures long long lifelife timetime

ObtainObtain the the specifiedspecified qualityquality FRP FRP structurestructure : : shearshear

LoadsLoads in in planeplane of of laminatelaminate byby resinresin

AvoidAvoid water water migrationmigration byby proper proper sealingsealingall holesall holes

InspectInspect onon regularregular basisbasis

ObtainObtain the the specifiedspecified qualityquality FRP FRP structurestructure

UV UV protectionprotection

UV UV degradationdegradation and and moisturemoisture penetrationpenetrationwillwill have have influenceinfluence lifelife time of time of anan FRP FRP coolingcooling towertower

The UV The UV raysrays willwill causecause the the decompositiondecomposition of of the the polymerspolymers holding the holding the fibrefibre glassglass togethertogether

FRP FRP structurestructure UV UV protectionprotection

SurfaceSurface veil veil materialmaterial of non of non wovenwoven polyester polyester fabricfabric to prevent fiber blow outto prevent fiber blow out

SurfaceSurface veil veil createscreates a a resinresin richrich surfacesurface areaareato provide to provide enhancedenhanced UV UV protectionprotection

OneOne milmil thicknessthickness of of surfacesurface veil =veil =2 2 ––

3 3 yearsyears

lifelife

timetime

STRUCTURAL RESIN 55-25%GLASS 45-75%WOVEN ROVEN ANDCONTINUOUS GLASS250 MILS OR MORE

CORROSION BARRIERRESIN 60-70 %GLASS 30-40%MAT OR CLOTH40-60 MILS

EXTERNAL LINERRESIN RICH 80-90%GLASS 10-20%

15-20 MILSSURFACING VEIL TYPE C10-20 MIL THICKNESS

FRP FRP structurestructure UV UV protectionprotection

FRP FRP structurestructure UV UV protectionprotection

0

10

20

3040

50

60

70

80

5 10 15 20 25 30Years

Midde East Climate European Climate

UsefulUseful

lifelife

of UV of UV projectedprojected

componentscomponents

FRP FRP structurestructure UV UV protectionprotection

HowHow

to to verifyverify

UV UV protectionprotection

qualityquality

? ?

Have samples of different Have samples of different weightweight veil veil materialmaterial forfor comparisoncomparison..VariationVariation in the in the visibilityvisibility of the of the ContiniousContiniousFilament Mat. Filament Mat.

ObtainObtain the the requiredrequired qualityquality FRP FRP structurestructure

Fire Fire retardancyretardancy

Fire Fire resistanceresistance

and and damagedamage

controlcontrol

of the of the FRP FRP structurestructure. .

FRP FRP structurestructure Fire Fire retardancyretardancy

Design Design withwith high high qualityquality, heat , heat resistantresistant / / firefireretardantretardant resinresin systemssystems, , ClassClass 1 type1 type

SpecifySpecify selfself extinguishingextinguishing

High High glassglass content = minimum content = minimum burnburn raterate

AdditionAddition AntimonyAntimony Trioxide Trioxide improvesimproves firefireretardingretarding

ObtainObtain the the requiredrequired qualityquality FRP FRP structurestructure

Major part of the Major part of the coolingcooling towertower costcostMost Most criticalcritical item item forfor the the coolingcooling towertower lifelifetime !time !

HowHow

to to obtainobtain

the the requiredrequired

qualityquality

? ?

ObtainObtain the the requiredrequired qualityquality FRP FRP structurestructure

1. 1. DemandDemand

coolingcooling

towertower

suppliersupplier

namesnames

the FRP the FRP sourcesource

and and askask

deliverydelivery

certificatescertificates

fromfrom

the the

FRP FRP manufacturermanufacturer..

2. Reserve the right to 2. Reserve the right to inspectinspect

beforebefore

deliverydelivery

to to verifyverify

QualityQuality

ProcessProcess

Map is Map is compliedcomplied

withwith. .

ObtainObtain the best the best qualityquality Fans Fans

ObtainObtain the best the best qualityquality FansFans

Fans are Fans are selectedselected forfor a a givengiven airflowairflow and and static static pressurepressure

Fan design parameters : Fan design parameters : diameter diameter ––

speed speed ––

nbrnbr

and and shapeshape

of of bladesblades

––

bladeblade

widthwidth

Fan design parameters Fan design parameters influenceinfluence ::costcost

––

power power consumptionconsumption

––

noisenoise

CoolingCooling towertower fans fans NoiseNoise definitiondefinition

SpecifySpecify

sound sound pressurepressurein dB(A) in dB(A) measuredmeasured

1,5 meter 1,5 meter

aboveabove

fan discharge fan discharge (per CTI (per CTI stdstd

ATC ATC ––

128)128)

CoolingCooling towertower fansfans NoiseNoise

CoolingCooling towertower fansfans ComparisonComparison -- 2000 ton 2000 ton towertower -- 196 m196 m³³/ sec @ 160 Pa / sec @ 160 Pa pressurepressure drop drop

FanFandia dia

NbrNbrBladesBlades RpmRpm

TipTipspeed speed

SoundSoundPowerPower

Fan Fan shaftshaftPower Power Fan Fan

ftft m/secm/sec dB(A)dB(A) kW kW US $ US $

1414 66 270.8270.8 60.560.5 100.3100.3 59.359.3 21002100

1616 77 193.9193.9 49.549.5 95.695.6 53.253.2 36003600

1818 55 186.8186.8 54.254.2 9999 4646 1350013500

18 *18 * 44 137137 4040 86.386.3 54.954.9 4500045000

CoolingCooling towertower fansfans Fan power Fan power vsvs costcost –– 2000 ton 2000 ton towertower –– 196 m196 m³³/sec @ 160 Pa /sec @ 160 Pa pressurepressure dropdrop

Fan dia Fan dia TowerTower priceprice Fan Power Fan Power

ftft %% kWkW

1414 -- --

1616 + 1, 25 %+ 1, 25 % -- 11 % 11 %

1818 +8 % +8 % -- 22 % 22 %

CoolingCooling towertower fansfans ComparisonComparison -- 5000 ton 5000 ton towertower -- 375 m375 m³³/ sec @ 160 Pa / sec @ 160 Pa pressurepressure dropdrop

FanFandia dia

NbrNbrBladesBlades RpmRpm Tip speed Tip speed

SoundSoundPowerPower

Fan Fan shaftshaftPower Power Fan Fan

ftft m/secm/sec dB(A)dB(A) kW kW US $ US $

2222 66 226226 44.244.2 106.3106.3 106.3106.3 95009500

2626 99 104.8104.8 43.543.5 97.997.9 87.187.1 2600026000

2626 66 89.789.7 37.237.2 90.690.6 104.2104.2 6000060000

2828 66 82.682.6 36.936.9 9090 102.3102.3 6500065000

CoolingCooling towertower fansfans Fan power Fan power –– noisenoise vsvs costcost -- 5000 ton 5000 ton towertower –– 375 m375 m³³/ sec @ 160 Pa / sec @ 160 Pa pressurepressure dropdrop

FanFandia dia

TowerTowerpriceprice Power Power

SoundSoundPower Power

ftft %% kWkW dB (A)dB (A)

2222 106.3106.3

2626 + 7 %+ 7 % -- 18 % 18 % 97.997.9

2626 20%20% --2%2% 90.690.6

2828 + 22% + 22% --4%4% 9090

ObtainObtain the the requiredrequired qualityquality Fan Fan stacksstacks

Fan Fan stacksstacks MaterialMaterial

HeightHeight : 6 : 6 –– 8 8 –– 10 ft 10 ft -- ……

MaterialMaterial : : ClassClass 1 1 –– flameflame spread rating 25spread rating 25((ClassClass

II and II and ClassClass

III = III = CheaperCheaper

!)!)

UV UV resistanceresistance ((gelcoatgelcoat 20 20 milmil).).

Access door Access door oror removableremovable panel panel

AssemblyAssembly hardware SST hardware SST

Fan Fan stacksstacks

MakeMake suresure fan deck fan deck floorfloor opening matches opening matches fan fan cylindercylinder

SmoothSmooth air air inletinlet

Fan tip Fan tip clearanceclearance : 0,5% fan dia: 0,5% fan dia

ObtainObtain the the requiredrequired qualityquality Air Air inletinlet louverslouvers

Water stays in… Sunlight stays out!

Air Air inletinlet louverslouvers Single pass Single pass louverslouvers

WaterdropletsWaterdroplets tendtend to to splashsplash out out whenwhen fans fans are are shutshut offoff. .

SunlightSunlight stillstill enters the enters the coolingcooling towertower basinbasin !!

Air Air inletinlet louverslouvers TwoTwo pass air pass air inletinlet louverslouvers

MinimiseMinimise splashoutsplashout

Direct Direct sunlightsunlight is is blockedblocked fromfrom the water the water insideinside the the towertower and and reducingreducing the the potentialpotentialforfor algaealgae formationformation ! !

Minimum Minimum pressurepressure drop drop

Air Air inletinlet louverslouvers TwoTwo pass air pass air inletinlet louverslouvers

TypicalTypical

twotwo

pass air pass air inletinlet

louverslouvers

ObtainObtain the the requiredrequired qualityquality Drift Drift eliminatorseliminators

ObtainObtain the the requiredrequired qualityquality Drift Drift eliminatorseliminators

Drift Drift ratesrates : 0,01 to : 0,01 to 0,00050,0005 % of % of towertower flowflowraterate

Drift Drift raterate functionfunction of type DE, air of type DE, air velocityvelocity, , water water loadingloading and spray and spray nozzlenozzle typestypes

Drift Drift eliminatorseliminators QualityQuality

Drift Drift raterate

dependendsdependends

onon: :

WaterloadingWaterloadingAir Air velocityvelocitySpray Spray nozzlenozzle arrangement arrangement

Drift Drift eliminatorseliminators Efficiency Efficiency confirmationconfirmation

AskAsk youryour coolingcooling towertower suppliersupplier namesnamesmanufacturermanufacturer of DEof DE

DemandDemand independent test independent test certificationscertificationsaccordingaccording toto acceptedaccepted standardsstandards

Air passes Air passes throughthrough

areaarea

withwith

minimum minimum resistanceresistance

Air bypass Air bypass reducesreduces coolingcooling effecteffectWater loss Water loss becausebecause of of higherhigher air air velocityvelocity

Drift Drift eliminatorseliminators ExecutionExecution onon sitesite

Drift Drift losseslosses Design Design considerationsconsiderations : air : air sealsseals

GoodGood coolingcooling towertower practisespractises Design Design considerationsconsiderations

Mechanical Mechanical equipmentequipmentFillFillWater distributionWater distribution

GoodGood coolingcooling towertower practisespractises

ObtainObtain

the the specifiedspecified

and correct and correct qualityquality

level !level !

ThankThank

youyou

Georges HoeterickxGeorges Hoeterickx