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Water Management Technologies
Weyerhaeuser_October 2007 - 1
Condensate ManagementMonitoring Condensate
Virginia DurhamMay 2008
Water Management Technologies
Weyerhaeuser_October 2007 - 2
Outline• Goals in condensate management• Monitoring
PurposeSamplingTestingMajor Streams
Contaminants Automatic dump systems
Water Management Technologies
Weyerhaeuser_October 2007 - 3
Condensate Management• Maximize quantity returned
Energy value
• Maximize qualityBoiler reliability(Condensate system reliability)
Water Management Technologies
Weyerhaeuser_October 2007 - 4
The cost of lost condensate
1 GPM: $4300 per year20 GPM: $1600 per week ($85,000/year)
in boiler fuel costAssuming :
$6/mmBTU fuel cost80 % boiler efficiency200 degF condensate70 degF make-up water
Water Management Technologies
Weyerhaeuser_October 2007 - 5
Monitoring Condensate QualityGoal:
Maximize condensate quantity and quality to provide economy and boiler protection
Contamination detectionTreatment program monitoring and controlPolisher performance monitoring and controlCondensate stream return control
Water Management Technologies
Weyerhaeuser_October 2007 - 6
Condensate quality― TAPPI Guidelines ―
30 mmhos
.05 - .1 ppm
.05 - .3 ppm
“Softened” water system (pressure dependent)
5 mmhos above “expected”Conductivity
< .01 ppmCopper
< .01 ppmIron
< .1 ppmSilica
Non -detectableTotal Hardness
High purityWater system
Parameter
From :
TAPPI Tips 0416-14
0416-03
Water Management Technologies
Weyerhaeuser_October 2007 - 7
Sampling – How?• Stainless steel sample line• Maintain adequate velocity/minimize line length• Run sample continuously• Cool sample
Follow ASTM D3370
Water Management Technologies
Weyerhaeuser_October 2007 - 8
Sampling – Where?• Routine Sampling
Critical streamsComposite streams prior to flash tanks/vented receiversBulk condensate return streams
• Non-routinePaper machine receiversOther?
Water Management Technologies
Weyerhaeuser_October 2007 - 9
Example Condensate System
Feedwater
Makeup
ReturnCondensate
Steam
Deaerator
Pulp Dryer
TurbineGenerator
PaperMachine
ResinPolisher
MagneticFilter
Boilers
evaporators Digester
Water Management Technologies
Weyerhaeuser_October 2007 - 10
Testing
ManualProgram PerformanceCorrosion Coupons
Manual:(Wet analysis, Sub-micron Filtration)Continuous:(Turbidimeters, Particle Counters)
Program Performance(Contamination)
Metals Testing
ManualContamination DetectionOxygen
ManualContamination DetectionHardness
Manual(Continuous)
Contamination DetectionSilica
ManualContinuous
Contamination DetectionConductivity
ManualContinuous
Program Chemistry/Contamination Detection
pH
Typical MethodPurposeTests
Water Management Technologies
Weyerhaeuser_October 2007 - 11
Testing
ManualProgram PerformanceCorrosion Coupons
Manual:(Wet analysis, Sub-micron Filtration)Continuous:(Turbidimeters, Particle Counters)
Program Performance(Contamination)
Metals Testing
ManualContamination DetectionOxygen
ManualContamination DetectionHardness
Manual(Continuous)
Contamination DetectionSilica
ManualContinuous
Contamination DetectionConductivity
ManualContinuous
Program Chemistry/Contamination Detection
pH
Typical MethodPurposeTests
Water Management Technologies
Weyerhaeuser_October 2007 - 12
pH Testing
• Cool sample to 77oF
Avoid loss of volatile species
Accurate pH measurement
Water Management Technologies
Weyerhaeuser_October 2007 - 13
9.5
9.0
8.5
8.0
7.5
7.0
75 100 125 150 175 200
Sam
ple
pH
Sample Temperature (Degrees F)
Effect of Temperature on Sample pH
Water Management Technologies
Weyerhaeuser_October 2007 - 14
Temperature compensation of pH• Some meters have 2 levels of compensation:
“electronic”“solution chemistry”
• Many meters simply address the “electronic”compensation and do not compensate for temperature effects on solution chemistry
Water Management Technologies
Weyerhaeuser_October 2007 - 15
Sample point location for pH testing• Be sure sample points provide meaningful results
Challenging for systems with high alkalinity make up water
Water Management Technologies
Weyerhaeuser_October 2007 - 16
mainreceiver
Paper Machine
vacuumpump
heatexchanger
wet enddryers
main sectiondryers
thirdsection
Water Management Technologies
Weyerhaeuser_October 2007 - 17
Testing
ManualProgram PerformanceCorrosion Coupons
Manual:(Wet analysis, Sub-micron Filtration)Continuous:(Turbidimeters, Particle Counters)
Program Performance(Contamination)
Metals Testing
ManualContamination DetectionOxygen
ManualContamination DetectionHardness
Manual(Continuous)
Contamination DetectionSilica
ManualContinuous
Contamination DetectionConductivity
ManualContinuous
Program Chemistry/Contamination Detection
pH
Typical MethodPurposeTests
Water Management Technologies
Weyerhaeuser_October 2007 - 18
Metals Testing• Manual
Wet chemistryironcopper
Sub-micron filtration
• ContinuousTurbidityParticle Counters
Water Management Technologies
Weyerhaeuser_October 2007 - 19
Sub-micron Filtration
Example of iron on a paper machine startup
Water Management Technologies
Weyerhaeuser_October 2007 - 20
Turbidity monitoring
• Indicator of particulate corrosion products
• Can be used for automatic diversion of condensate
• Correlation of turbidity with contamination levels is required
Water Management Technologies
Weyerhaeuser_October 2007 - 21
Condensate
Sample
ToPowerHouseDumped Condensate
Coo
ler
Turbidity MonitoringTurbidity
Meter
Water Management Technologies
Weyerhaeuser_October 2007 - 22
Testing
ManualProgram PerformanceCorrosion Coupons
Manual:(Wet analysis, Sub-micron Filtration)Continuous:(Turbidimeters, Particle Counters)
Program Performance(Contamination)
Metals Testing
ManualContamination DetectionOxygen
ManualContamination DetectionHardness
Manual(Continuous)
Contamination DetectionSilica
ManualContinuous
Contamination DetectionConductivity
ManualContinuous
Program Chemistry/Contamination Detection
pH
Typical MethodPurposeTests
Water Management Technologies
Weyerhaeuser_October 2007 - 23
Conductivity Monitoring• Typically used as an
indication of raw water and liquor contamination
• Portable meters are a good tool
• Continuous monitoring is a critical component to a boiler protection program
Water Management Technologies
Weyerhaeuser_October 2007 - 24
Condensate
ConductivityProbe
Sample
ToPowerHouseDumped Condensate
ConductivityMeter
Coo
ler
Conductivity Monitoring
Water Management Technologies
Weyerhaeuser_October 2007 - 25
Automatic conductivity dumpsconsiderations
• Location of probeDead time – be sure that probe/meter can detect and divert condensate before contaminants reach the valve
• Set point point for dumpingLow enough to catch intrusion while avoiding nuisance alarms
• Preventive maintenanceExercise the probe, meter, and the valves.
Water Management Technologies
Weyerhaeuser_October 2007 - 26
Minimize dead time:
Line length and sample flow
Condensate
ConductivityProbe
Sample
ToPowerHouseDumped Condensate
ConductivityMeter
Coo
ler
Conductivity Monitoring
Water Management Technologies
Weyerhaeuser_October 2007 - 27
Set Point for dumping:
Low enough for protection
Condensate
ConductivityProbe
Sample
ToPowerHouseDumped Condensate
ConductivityMeter
Coo
ler
Conductivity Monitoring
Water Management Technologies
Weyerhaeuser_October 2007 - 28
Condensate
ConductivityProbe
Sample
ToPowerHouseDumped Condensate
ConductivityMeter
Coo
ler
Conductivity Monitoring
Preventive Maintenance:
Exercise the valve
Water Management Technologies
Weyerhaeuser_October 2007 - 29
Automatic conductivity dumpsconsiderations
• Location of probeDead time – be sure that probe/meter can detect and divert condensate before contaminants reach the valve
• Set point point for dumpingLow enough to catch intrusion while avoiding nuisance alarms
• Preventive maintenanceExercise the probe, meter, and the valves.
Water Management Technologies
Weyerhaeuser_October 2007 - 30
Testing
ManualProgram PerformanceCorrosion Coupons
Manual:(Wet analysis, Sub-micron Filtration)Continuous:(Turbidimeters, Particle Counters)
Program Performance(Contamination)
Metals Testing
ManualContamination DetectionOxygen
ManualContamination DetectionHardness
Manual(Continuous)
Contamination DetectionSilica
ManualContinuous
Contamination DetectionConductivity
ManualContinuous
Program Chemistry/Contamination Detection
pH
Typical MethodPurposeTests
Water Management Technologies
Weyerhaeuser_October 2007 - 31
Spectrophotometer
• Low level hardness testing
• Silica
• Wet testing for iron, copper
Water Management Technologies
Weyerhaeuser_October 2007 - 32
Oxygen Testing• Used typically as a troubleshooting tool in
condensateManualContinuous
Water Management Technologies
Weyerhaeuser_October 2007 - 34
Typical Routine Monitoring
ManualProgram PerformanceCorrosion Coupons
Manual:(Wet analysis, Sub-micron Filtration)Continuous:(Turbidimeters, Particle Counters)
Program Performance(Contamination)
Metals Testing
ManualContamination DetectionOxygen
ManualContamination DetectionHardness
Manual(Continuous)
Contamination DetectionSilica
ManualContinuous
Contamination DetectionConductivity
ManualContinuous
Program Chemistry/Contamination Detection
pH
Typical MethodPurposeTests
Water Management Technologies
Weyerhaeuser_October 2007 - 35
Test Sensitivity Issues• “Set-point” for dumping on conductivity• Choice of hardness test
Use spectrophotometer
• Silica/hardness test more sensitive than conductivity for raw water intrusion
• Is conductivity sensitive enough for low level acid intrusion from Chlorine dioxide generator?
Water Management Technologies
Weyerhaeuser_October 2007 - 36
Major Streams and their Contaminants
Feedwater
Makeup
ReturnCondensate
Steam
Deaerator
Pulp Dryer
TurbineGenerator
PaperMachine
ResinPolisher
MagneticFilter
Boilers
evaporators Digester
Water Management Technologies
Weyerhaeuser_October 2007 - 37
Major Streams
Corrosion ProductsAcidChlorine Dioxide Generator
Corrosion ProductsMill WaterCondensers/Mill Water Heaters
Corrosion ProductsOilLube Oil System
Corrosion ProductsGlycolGlycol System
Corrosion Products (Iron)Corrosion Products (Copper)Pulp Dryer
Corrosion ProductsLiquorDigester Liquor Heaters
Corrosion ProductsLiquorEvaporators/Concentrators
Mill WaterCorrosion Products (Iron)Paper Machine
Minor ContaminantsMajor ContaminantStreams
Water Management Technologies
Weyerhaeuser_October 2007 - 38
Boiler protection though automatic dump systems
ConductivityOther streams with possible
liquor, raw water contamination
Turbidity, (Conductivity)Paper machine
ConductivityEvaporator
Meter/Dump SystemStream
Conductivity, (pH)Chlorine Dioxide Generator
ConductivityDigester
Water Management Technologies
Weyerhaeuser_October 2007 - 39
Dumping Practices• Automatic Systems - preventive maintenance
Full testing of systemFrequency?
• Optimization Opportunity?Allow polishers/filters to do more work…
Requires a rigorous study of polisher system performance during upset conditions to avoid risk to boilerOngoing monitoring of polisher system effluent must be in place
• Monitoring of flows ContinuousWalk-downs
Also provides information on leaks
Water Management Technologies
Weyerhaeuser_October 2007 - 40
Summary• Condensate monitoring program is critical for boiler protection
• Test method sensitivity should be considered when monitoring forcontamination
• Maintenance and configuration of dump systems require attention to assure protection
• Look closely at polisher/filter operation and potential to return more condensate