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CILEGON COMBINED CYCLE POWER PLANTAUXILIARY BOILER – PLN PROJECT
MITSUBISHI HEAVY INDUSTRIES LTD.
Training ProgramAuxiliary Boiler 12 Ton/Hr , 12 BargBy. PT Basuki Pratama Engineering
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Items of Training
I. PrefaceII. Utilizing EquipmentsIII. System DescriptionIV. Operation SequenceV. Maintenance VI. Boiler Operation Water Treatment
P R E F A C E
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What is that Steam Boiler BHS-12000-LO ?
II. Utilizing Equipments
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1 Unit Steam Boiler BHS-12000-LO (10QHA01AC101)Capacity : 12 Ton/Hr , 12 BargDesign / Operating Pressure : 12 Barg / 9 BargEfficiency : 89 % (min)Type of Fuel : Diesel OilMax Fuel Consumption @ Full load : 812 Kg/Hr
1 Unit Diesel Oil Burner (10QHH01AV101)Brand / Type : OILON / KP-700 M-IICapacity (max) : 812 Kg/HrDriving Motor : 26 KWControl : Fully – AutomaticRegulation : Fully – Automatic
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1 Unit Superheater (10QLB11AC001)Steam Capacity : 10,000 Kg/HrSteam Temperature : 260 oCOperating Pressure : 8 BargDesign Pressure / Temp. : 12 Barg / 300 oCTest Pressure : 18 Barg
2 Units Feed Water Pump (10QLA11AP101/102)Conveying Capacity : 12,000 Liter/HrDelivery Head : 132 M Motor Capacity : 11 KW
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1 Unit Feed Water Tank w/Deaerator(10QLA11AC101 / 10QLA11BB101)Operating Pressure : 0.13 BargDesign Pressure : 1 BargFWT Capacity : 12,000 LtrDeaerator Capacity : 12 M3/Hr FWT Dimension : Dia 1900 x 4200 S/SDeaerator Dimension : Dia 650 x 1400 S/S
1 Unit Chimney (10QHN01BV101)Dimension : Dia 785 X 20,000 HeightAccessories : - Insulation & Cladding up to 2 M Height
- Free Standing
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1 Unit Blow Down Tank (10QHF01BB001)Dimension : Dia 600 x 1,200 S/SDesign Pressure / Temperature : 1 Barg / 120 oCOperating Pressure : Atmosphericc/w : Vent Head & Silincer
1 Unit Daily Fuel Tank (10QHH01BB101)Capacity : 25,000 LiterDimension : Dia 2500 x 5000 S/SDesign Pressure : AtmosphericOperating Pressure : Atmospheric
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3 Units Sample Cooler(10QUA03AC001 ; AC002 ; AC003)
Dimension : Dia 100 x 300 HeightMaterial : SUS 304Cooling Water Inlet Valve : 3/8”Hot Water Inlet Valve : DN6 – PN40
1 Unit FWT Dosing Device (10QLF11AP201)
Diaphragm pump type : Pulsatron – LPD3S2-365
Max. Capacity : 1.9 Ltr/HrWorking Pressure : 17 BargVoltage : 230VAC 50 Hz / 0.5A 1 PhaseC/W Storage Tank
Tank Contents : 650 LiterMaterial : Polyethylene
C/W MixerType : MIX6/2 “EMEC”Motor Rating : 110 W
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1 Unit Boiler Dosing Device (10QLF11AP201)
Diaphragm pump type : Pulsatron – LPF4S2-365
Max. Capacity : 3.2 Ltr/HrWorking Pressure : 17 BargVoltage : 230VAC 50 Hz / 0.5A 1 PhaseC/W Storage Tank
Tank Contents : 650 LiterMaterial : Polyethylene
C/W MixerType : MIX6/2 “EMEC”Motor Rating : 110 W
III. System Description
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Process Flow Diagram
Piping & Instrumentation Diagram
10QLF11AP101BOILER DOSING DEVICE
10QUA03AC001,10QUA03AC002 10QHN01BV101CHIMNEYFEED WATER PUMP
10QLA11AP101/102DAILY FUEL TANK
10QHH01BB101 10QLA11AC101&10QLA11BB101FEED WATER TANK WITH DEAERATOR
10QHA01AC101STEAM BOILER BHS-12000-LO
10QHH01AV101DIESEL OIL BURNER10QUA03AC003
SAMPLE COOLER
10QLB11BB901CONDENSATE POT
10QLB11AC001SUPERHEATER
10QHF01BB001BLOW DOWN TANK CONDENSATE POT
10QLA11BB901 10QLF11AP201FWT DOSING DEVICE
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Front Control Panel
Inside Control Panel
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Feed Water System
Logic Diagram Feed Water Tank
1
R
L13
SOLENOID VALVE #1ON
OPEN10QLA11 AA002
NAND
NAND
MANUAL
AUTO
OFF
WATER INLET VALVE 2AUTO/OFF/MANUAL
S8
OR S
R
L14
SOLENOID VALVE #2ON
OPEN10QLA11 AA007
2
FCV 159
FCV 161
S
AND
AND
10QLA11CL01QN
BY PASS LEVELINDICATOR
L4
L3
L2
L1WATER HIGH
HIGH LEVEL REGULATION
MIDDLE LEVEL REGULATION
LOW LEVEL REGULATION
NAND
NAND
WATER LEVEL REACHTHE ELECTRODE = CLOSED
L4
WATER LEVEL REACHTHE ELECTRODE = CLOSED
L5ALARM
AUDIBLE
FEED PUMPDRY RUN
H10
10QLA11 AP002
Off10QLA11 AP001
SOLENOID VALVE 1
SOLENOID VALVE 2
LIS 144
F.W. PUMP 1 & 2
H11
HW ALARMFW TANK
AUDIBLEALARM
DISTURBANCE
DISTURBANCE
BS
BS
WILL CLOSE WHENLEVEL REACH L3
SOLENOID VALVE 2
SOLENOID VALVE 1
LEVEL REACH L2WILL CLOSE WHEN
FIELD INPUTS CONTROL SWITCHES L O G I C LAMP INDICATORS (LCP) FIELD OUTPUT
NAND
NAND
MANUAL
AUTO
OFF
WATER INLET VALVE 1AUTO/OFF/MANUAL
S7
OR
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Feed Water Tank
InstrumentBy-pass level indicator 5 switch (LIS 144) :Used for control level feed water tank and level indicatorSolenoid valve 1 (FCV 159) and Solenoid valve 2 (FCV 161) :Valve water inlet feed water tankPressure switch (PSL145) :Used for monitoring of pressure in water tank.
System DescriptionWater inlet valve can operate manually and automatically with selector switch water tank valve in control panel. Auto status, valve operate depend on level switch. If water level :Above L1; valve1 & valve2 close, alarm FWT high, digital input FWT on, and disturbance indicator FWT high ON.Above L2; valve1 & valve2 close.Above L3; valve1 open & valve2 closeBelow L4; valve1 & valve2 openBelow L5; valve1 & valve2 open, alarm FWT low, FWP off, digital input FWT low, disturbance indicator FWT ON.
If pressure feed water tank below setting (set=0.1 bar), pressure switch signal to digital input feed water tank pressure to low
Solenoid valve
Pressure switch
L1
L3
L5
L4
L2
By-pass levelindicator
Logic Diagram Dosing System
DOSING PUMP 2
AND
HV 177
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10QLF11 AP201START
ONDOSING PUMP 2
L2
R
SOR
ORS2
AUTO/OFF/MANUALDOSING PUMP 2
OFF
AUTO
MANUAL
FIELD INPUTS CONTROL SWITCHES L O G I C LAMP INDICATORS (LCP) FIELD OUTPUT
FCV 159FCV 161
Service Water InletSolenoid Valve
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Feed Water Tank Dosing Pump
InstrumentDosing pump :Supply hydrazine and amine from feed water tank dosing to feed water tankMixer pump :Mix hydrazine and amine in feed water tank dosing
System Description Dosing device can operate manually and automatically with selector switch dosing pump2 in control panel. Auto status, dosing device operate depend on solenoid valve1 water inlet feed water tank. Dosing pump
Mixer
Fuel Oil System
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Logic Diagram Daily Fuel Tank
OIL HIGH
HIGH LEVEL REGULATION
LOW LEVEL REGULATION
OIL LOW
INTERLOCKTO BURNER
10QHH01
LCV 239
R
SOR
AUTO/OFF/MANUALOIL INLET VALVE
OFF
AUTO
MANUAL
S9 AND
INDICATORBY PASS LEVEL
FIELD OUTPUTLAMP INDICATORS (LCP)L O G I CCONTROL SWITCHESFIELD INPUTS
(OFF BURNER)
AA00210QHH01
SOLENOID VALVEOIL INLET
HIGHOIL LEVEL
L16
L15
VALVE OIL INLET ON
LOW
OIL LEVEL
L17
AND
L1
L2
L3
L4
Daily Fuel Tank Level
Instrument
By-pass level indicator (LI 215) with 5 switch (LT 218) :Used for control level fuel oil and level indicatorSolenoid valve (LCV 239) :Valve fuel oil inlet daily fuel tank
System DescriptionFuel oil inlet valve can operate manually and automatically with selector switch oil inlet valve in control panel. Auto status, valve operation depends on level switch. If oil level :Above L1; valve close, digital input fuel oil tank level high on, and indicator oil to high on.Above L2; valve closeAbove L3; valve open Below L4; valve open, indicator oil to low on, alarm oil tank to low, burner off (manual ON)Below L5; valve open, digital input fuel oil tank level to low on
Solenoid valve
L1
L3
L5
L4
L2
By-pass levelindicator
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Oil Measurement
InstrumentOil flow meter (FQI 190) :Used for measuring oil flow daily fuel tank to boiler Oil totalizer :Display water totalizer in control panelOil flow rate :Display water flow in control panelRecorder :Record oil flow in control panel.
System DescriptionFlow meter signal to oil totalizer, oil flow rate, oil flow recorder, and auxiliary analog output (4-20mA) fuel firing rate (terminal X3 74;75).
Totalizer
Recorder
Flow rate
Steam Outlet & Start-up Line
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Saturated Steam Temperature
InstrumentTemperature sensor PT 100 ( TE 221) :Measuring saturated steam temperatureTemperature display (TI 141) :Display saturated steam temperature in control panel
System Description Temperature sensor signal to temperature display for saturated steam temperature. Sensor PT 100
Temperature Display
Logic Diagram Blow out
FOR TEMP.COMPENSATION
PRESS. TRANSMITTERFT 137 BUILT IN SET POINT=2 Bar
S12
CLOSE
OFF
OPEN
CF0110QLB11
137
PID CONTROLSTART
10QLB11AA903
10QLB11AA903
Controller Burner
P
I
D
FT
SELECTOR
BLOW OUT
SERVO MOTORBLOW OUT
FIELD INPUTS CONTROL SWITCHES L O G I C LAMP INDICATORS (LCP) FIELD OUTPUT
Press. After Super Heater
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Steam Flow Meter and Blow Out Steam
Instrument Steam flow meter (FT 137) :Used for measuring steam from boilerSteam display and controller (FC139) :Display steam flow in control panelValve blow out (FCV 224) :Valve for steam start up
System DescriptionFlow meter signal to steam totalizer, steam display controller, and steam flow recorder in control panel. Blow out valve can operate manually and automatically with selector switch blow out in control panel. Auto status, valve open (blow out steam) if pressure super heater not reach (set = 2 bar) and burner not OK.
Steam displayand controller
Actuator valve Valve
Logic Diagram Super Heater
FIELD INPUTS CONTROL SWITCHES L O G I C LAMP INDICATORS (LCP) FIELD OUTPUT
260ºC
> 960 kg/hr
> 7.7 barg
FT137
10QLB11CF01
CT14QP10QLB11
211
207
10QLB11CP01QB
AA008
PRESSURE
10QLB11
10QLB11 CT09QNREGULATION
SUPER HEATER FLAPSERVO MOTOR
TEMPERATURE SUPER HEATER
SET POINT
TE
D
I
P
FLOW
PT
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Super heater
InstrumentTemperature sensor PT 100 ( TE 211) :Measuring super heater temperature steamTemperature display and controller (TIC 213;TI 210) :Display temperature super heater steam in control paneland control damper super heaterActuator damper super heater :Damper for control temperature super heater steam
System DescriptionTemperature sensor signal to temperature super heater display in control panel and auxiliary analog output (4-20mA) super heater steam temperature (terminal X3 76;77).Damper operate regulation if flow steam reach 960 kg/h and pressure > 7.7 bar.If temperature 280°C digital input super heater temp. high on.If temperature 300°C disturbance indicator super heater temp. to high on
Actuator damper super heater
Sensor PT 100
Temperature steam display and controller
Main Steam Valve
InstrumentPressure Transmitter :Pressure Transmitter are used to measure pressures in liquids and gases. The pressure is converted into an electrical signalPressure super heater display and controller :Display Pressure super heater steam in control paneland control damper burner Actuator steam out :Actuator for control valve saturated steam out Valve saturated steam out :Valve for saturated steam out
System DescriptionValve saturated steam out operate with selector switch main steam valve in control panel ( open-close valve ). if pressure reach 8 bar in pressure display control panel operator can operate this switch.
Valve
Actuator steam out
Pressure TransmitterPressure super heater steam
display and controller
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Blow Down Tank & Drain System
Logic Diagram Blow Down Tank
OPEN
Below Set Point = Logic 0Above Set Point = Logic 1
TEMPERATURE CONTROL
SET POINT
TE
OFF
ONCT0110QHF01
MANUAL
AUTO
OFF
TEMPERATURE HIGH
BLOWDOWN TANKAUTO/OFF/MANUAL
S3
OR S
R
L3
BLOWDOWN TANKON
COOLING WATER INSOLENOID VALVE
10QHF01TIC231
232
10QHG01AA002
SET POINT= 50 C
AND
Temperature Controller will Open/CloseSolenoid Valve automatically at set point value
FIELD OUTPUTLAMP INDICATORS (LCP)L O G I CCONTROL SWITCHESFIELD INPUTS
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Blow Down Tank
InstrumentTemperature sensor PT 100 ( TE 232) :Measuring blow down tank temperatureTemperature controller (TIC 231) :Control for blow down tank temperatureSolenoid valve (TCV 233) :Valve service water inlet blow down tank
System Description Service water inlet valve can operate manually and automaticallywith selector switch blow down tank valve in control panel. Auto status, valve operation depends on setting temperature (set = 50°C). If temperature over setting valve open and conversely.if temperature increase (>60°C), digital input blow down tank discharge temperature high on.
Sensor PT 100
Temperature controller
Solenoid valve
Steam Boiler System
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Steam Boiler System
1. Bottom Blow Down
InstrumentBlow down controller (PRS-7b) : Generates a control pulse which, after the preset blow down interval, operates the three way solenoid valve.Three way solenoid Valve :Solenoid for control valve intermittent blow down Valve intermittent blow down (BDV 115) :Intermittent blow down valve boilerSightglass (FG123) :Visual supervision of condensate conditions in heat exchangers and flow conditions pipelines. It clearly indicates loss of live steam, banking up of condensate or the presence of air.
System DescriptionController turn actuates the rapid action blow down valve by means of compressed air and closes it again at end of the pulse (blow down) duration. The blow down intervals can be adjusted.
Schematic layout
Three way solenoid valveAnd strainer
Sightglass
Logic DiagramSurface Blow Down
FIELD OUTPUTLAMP INDICATORS (LCP)L O G I CCONTROL SWITCHESFIELD INPUTS
124CE
CONDUCTANCE10QHA01
SWITCHDESALTING ON/OFF
SERVO MOTORDESALTING VALVE
LKER 1LIMITER
OPERATION
BT00110QHA01
CONDUCTIVITYREGULATOR ANDDESALTING
ELECTRODE
CT01QP10QHA01
AA005
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Steam Boiler System
2. Surface Blow Down
InstrumentConductivity Electrode (CE 124) :Monitoring of condensate return to boiler to detect water any penetration of acid, alkalis etc.Continuous blow down controller (LRR 1-5b) :Automatically controlled continuous blow down to reduce blow down wastage and increase operating safety.Control Valve (CCV 122) :Motorized control valves for continuous blow down system of steam boiler.
System Description Surface blow down can operate manually and automatically with selector switch blow down valve in control panel.Automatic system work depends on value setting. If condensate boiler over setting value, valve open and operate conversely
Conductivity electrode
Logic DiagramBoiler Water Level Control
OFF Burner (Auto ON)
OFF Burner (Manual ON)
AUDIBLEALARM
BS
L8
EXTRA LOWWATER LEVEL
LEVELLOW WATER
L6
AUDIBLEALARM
BS
L7
HIGH WATERLEVEL
BOILER
NRS 1-2b
LELL104
105
106
103
ELECTRODE
CL04QN10QHA01
10QHA01CL06QN
ELECTRODE
LELL WATER LEVEL CONTROLNRS 1-7b
10QHA01
MOTORIZED VAVESERVO MOTOR
AA02610QHA01
Feed Water PumpAND
SERVO DRIVEMIN. POSITION SWITCH
10QHA01AA026
SWITCH OFF DELAY
ZS
AND
A
CL08QN10QHA01
NRR 2-2eCONTROLWATER LEVEL CONTINUOUSLT
CONTINUOUS WATER
CL07QN10QHA01
LEVEL PROBE
10QHA01
LEVEL CONTROLHIGH & LOW WATER
ELECTRODE
10QHA01CL05QN
HIGH WATER
LEHH
FIELD OUTPUTLAMP INDICATORS (LCP)L O G I CCONTROL SWITCHESFIELD INPUTS
Control
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Steam Boiler System
3. Boiler Water Level Control
InstrumentLevel electrode (LELL 104; LEHH 103) :Signaling of level conductive (Low level alarm, high level alarm).Level electrode (LELL 105) :Signaling of level conductive (Extra low level alarm).Level Probe (LT 106) :Level probe for modulating level control boiler.Level Switch (NRS 1-2b) :Control for low level and high level boilerLevel Switch (NRS 1-7b) :Control for extra low level boilerLevel controller (NRR 2-2e) :Control valve for feed (fill) or drain (discharge) for modulating level boilerActuator Valve (LCV 184) :Motorized control valve modulating level boiler.Lamp indicator (LI 107) :Indicator for dangerous level water in boiler.boiler level :Indicator level boiler in control panel
Steam Boiler System
System DescriptionControl valve
Valve open regulation depend on monitoring probeLT 106 in boiler.If low level (LELL 104 ) reach, burner auto interlock, lamp indicator water level low and Digital input boiler water level low on.If high level (LEHH 103) reach feed water pump interlock, lamp water level high on, Digital input boiler water level high on and alarm high level boiler.If extra low level (LELL 105) reach, lamp water level extra low on, digital input boiler water level to low on, alarm extra low level boiler, and extra low level indicator in panel.
LT 106 NRR 2-2e
LCV 184
Sensor Controller Valve
Actuator valve
Indicator lamp
Valve
Level boiler
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Steam Boiler System
4. Pressure Switch and Pressure Limiter
InstrumentPressure switch regulation (PSHL 110) and Pressure switch limiter (PSHH 111) :Used for controlling and monitoring of pressure in steam boiler.
System DescriptionIf pressure boiler over pressure switch regulation setting (9.5 bar); burner interlock (auto operate), pressure high indicator panel on, display fault in panel, and digital input steam pressure high on.If pressure boiler over pressure switch limiter setting (10 bar); burner interlock (manual operate), pressure high indicator panel on, digital input steam pressure to high on
Pressure switch
Pressure limiter
Logic DiagramOperation Burner
10QHH01AV101
OIL PUMP MOTOR
PRESSURE SWITCH* MANUAL RESET ON
WATER LEVEL LOW
OIL LEVEL LOW
WATER LEVELEXTRA LOW
L21
BURNERON
AND
AND
S
R
OR
110
OFFAV101
10QHH01
10QHH01AV101
10QHH01DPOO1
LAL 2.25CONTROLLER
AUTOMATICBURNER
FLAME INTENSITY
10QHH01
FLAME SENSOR
CR001 IGNITION TRANSFORMER
SERVO MOTORCOMPOUND REGULATOR
BLOWER MOTOR
AV10110QHH01
DISTURBANCES
CP03QN
NOT HIGHPRESSURE BOILER
10QHA01
PSHL
BU
RN
ER
CO
NTR
OL
S13
INCREASE
STEADY
DECREASE
AUTO
BURNER START/FAILURE RESET
FIELD OUTPUTLAMP INDICATORS (LCP)L O G I CCONTROL SWITCHESFIELD INPUTS
CONTROLLERSTART PID
1. Control Blow Out2. Pressure saturated
steam control
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Logic DiagramControl Damper Burner
SET POINT= 8.5 Bar
Control blow Out
207
REGULATOR
PID CONTROLSTART
TRANSMITTER
10QHA01AV101
OPEN/STOP/CLOSEDCONTROLLER IN MANUAL MODE
SWITCH S13REF. SH. NO. 33
START CONTROLLER
SERVO MOTORCOMPOUND REGULATOR
A
T
AV101
SET POINT
PT
PRESSURE D
I
P
COMPOUND
10QHH01PRESSURE CONTROLLER BURNER
CP01QB10QLB11
POSITION
FIELD INPUTS CONTROL SWITCHES L O G I C LAMP INDICATORS (LCP) FIELD OUTPUT
Burner controller
Steam Boiler System
5. Burner
InstrumentAutomatic burner controller :Used to control Burner of steam boiler.Light oil Burner
System DescriptionBurner operate with push button (start / stop burner).Damper burner can operate manually and automatically with selector damper switch in control panel.Burner off if one of this condition happens : Boiler pressure too high, boiler extra low, and oil low level and must start again.Operating burner control with automatic burner controller.Time sequence diagram shows burner operation systemRegulation burner depends on pressure saturated steam
Burner Controller
Burner
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Time Sequence Diagram
Boiler Dosing Pump
DOSING PUMP 1
AND
HV 177
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10QLF11 AP101START
ONDOSING PUMP 1
L1
R
SOR
ORS1
AUTO/OFF/MANUALDOSING PUMP 1
OFF
AUTO
MANUAL
FIELD INPUTS CONTROL SWITCHES L O G I C LAMP INDICATORS (LCP) FIELD OUTPUT
FWP 1FWP 2
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Boiler Dosing Pump
InstrumentDosing pump :Supply phosphate from boiler dosing to feed water tankMixer pump :Mix phosphate in boiler dosing
System Description Dosing device can operate manually and automatically with selector switch dosing pump2 in control panel. Auto status, dosing device operation depends on solenoid valve1 water inlet feed water tank.
Dosing pump
Mixer
Logic DiagramFeed Water Pump Operation
OR
ANDAND
AND
OR
OR
S
R
S
R
L9
F.W PUMP 1OPERATION
L10
F.W PUMP 2OPERATION
10QLA11 AP101F.W. PUMP 1
10QLA11 AP102F.W. PUMP 2
F.W. PUMP 2
F.W. PUMP 1
PUMP 2 TRIP
PUMP 1 TRIP
DEAERATOR
OR
3
4
S5
MANUAL
AUTO
OFF
SELECTOR FEED WATERAUTO/OFF/MANUAL
S6
PUMP 2
PUMP 1
OFF
SELECTOR FEED WATERPUMP1/OFF/ PUMP2
OR
AND
AND
BOILERLEVEL NOT HIGH
FIELD OUTPUTLAMP INDICATORS (LCP)L O G I CCONTROL SWITCHESFIELD INPUTS
AND
AND
AND
AND
LEVEL NOT LOW
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Feed Water Pump
InstrumentFeed water pump (130) :Pump from feed water tank to boiler Pressure Indicator (PI 131) :Indicate pressure in line feed water pump
System Description There has two feed water pump operate interlock.Each feed water pump can operate manually and automatically with selector feed water pump in control panel. In auto status, pump operation depends on high level boiler, and feed water tank level low.If a pump trips, trip pump indicator in control panel on, display feed water pump trip in control panel, digital input feed water pump trip on.pressure gauge shows pressure in line of feed water pump
Feed Water Pump
Pressure Indicator
Flue Gas Temperature
InstrumentTemperature sensor PT 100 ( TE 140) :Measuring flue gas temperatureTemperature display (TI 141) :Displaying flue gas temperature in control panel
System Description Temperature sensor signal to temperature display for flue gas temperature. Sensor PT 100
Temperature Display
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Feed Water Measurement
InstrumentFeed water flow meter (FQI 175) :Used for measuring water flow from feed water tank to boilerWater totalizer :Display water totalizer in control panelWater flow rate :Display water flow in control panelRecorder :Record water flow in control panel.
System DescriptionFlow meter signal to water totalizer, water flow rate, and water flow recorder.
TotalizerFlow rate
Recorder
IV. Operation Sequence
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Control Panel
1. Operate Main Switch (Q0) to ON positionView Voltage (R-S; R-T; S-T; =380 Volt) in KWH meter
2. Pull Emergency Switch (ES)View lamp Power On (L0) operate
3. All Breaker in ON position (inside control panel) - Feed water pump 1 (-Q1)- Feed water pump 2 (-Q2)- Burner Fan (-Q3)- Oil pump (-Q4)- Dosing pump boiler (-Q5)- Dosing pump feed water tank (-Q6)- Socket 220 volt (-Q7)- Transformer for heater (-Q8)
4. Operate feed water tank - Selector switch water tank valve 1(-S7) in auto position- Selector switch water tank valve 2(-S8) in auto position
feed water valve 1 and valve 2 indicator ON, feed water valve 1 and valve 2 will off when level water tank reach high level
5. Operate dosing pump 2 (dosing boiler) - Selector switch dosing pump 2 in auto position
6. Operate oil inlet valve - Selector switch oil inlet valve in auto position
7. Operate feed water pump Wait after feed water tank level high
- Selector switch operational pump in auto position - Selector switch feed water pump in position pump1 or pump2
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8. Operate dosing pump 1(dosing feed water tank) - selector switch dosing pump 1in auto position
9. Operate blow down tank - selector switch blow down tank valve in auto position
10. Check alarm and disturbance indicatorNo sound/indicator alarm and disturbance indicator no fault.
11. Operate boiler - push start burner
12. Operate blow out - selector switch blow out in auto position
13. Operate main steam - if pressure reach 8 bar in display pressure and temperature reach 260 °C in control panel, selector switch main steam can operate in open position.
1. Emergency switch2. High water level3. Burner Disturbance4. Extra low level5. Over load F.W.P 16. Over load F.W.P 27. Over load burner8. Steam pressure high9. S.H steam temperature to high10. Feed water tank low 11. Feed water tank high
1. Emergency switch2. High level boiler3. Boiler extra low level4. Pressure to high5. Burner fail 6. Fuel oil tank to low7. Feed water tank high8. Feed water tank low
Disturbance indicatorAlarm
V. Maintenance
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Operating Log Book
A. Records of daily checks and servicing operations as well as other checks must be kept in an operating log book and signed daily by the responsible boilerman(operating personnel). In the case of some installation, this operating log book may be demanded as a prerequisite for the operating permit. Recurring test carried out by the technically competent person must also be entered in this operating log book. The forms appended to these operating instruction should be used for this purpose. When using boilers with superheaters, the operator must enter details of the hot steam temperature at brief intervals (at least every 30 minutes) in a separate sheet, along with details of the date and time, if no use has been made of a hot steam temperature control and if the superheater is installed in the are of high exhaust gas temperature. Here damage may occur if operation is not carried out conscientiously.
B. The boilerman’s superior must convince himself at least weekly of proper operation and servicing of the steam boiler installation and must note this on the rear of the sheet in the operating log book along with his signature and the date
Daily Checks and Servicing
A. Prior to start up of the installation and when each shift commences, the operating personnel (boilerman) must convince themselves of the installation’s proper operating condition.
B. The function of the water level limiters must be checked daily and at the start of each shift, unless they are self monitoring,i.e. special-design, devices. External devices must be blown out
C. Temperature and pressure limiters need not be checked daily. The intervals for these units depend on their nature-refer to weekly checks and servicing.
D. The time intervals for checking safety valves must be agreed by the operator and technical expert considering the service life of the sealing faces, daily checking is not recommended.
E. Blowing out Water level indicators and external feed water controllers and limiters must be blown out, attention being paid to the necessaryoperating sequence for shut-off and blown out valves.
F. Checks of all fire systemsf.1. Keep the fire chamber free from residues and coke sedimentf.2. Smoke-free combustionf.3. Correct oil temperature – when using heavy fuel oilf.4. Suitable oil pressure
G. Checks to be carried out when using heavy fuel oilg.1. Gas pressure
H. Water analysisRefer to the operating log book and the water directivesNotePay attention to the operating instructions issued by the supplier of the water treatment plant. Devices or checking the feed water generally do not suffice for checking the boiler water. Please enquire in cases of doubt.
I. Boiler blow downJ. Check sealing points and lock them and, if necessary, retighten them and renew the packingsK. Important note
If controllers are rendered inactive by malfunction, the installation must be observed continuously if its operation is continued. If safety devices should fail, please inform our Customer Service and, if necessary, shut down the installation and inform the installer for the installation of BASUKI representative in your area, or directly to us (refer to our contact address & phone/fax numbers)
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Weekly Checking and Servicing
A. Maximum water level ensuring facility in the case of hot steam boilers.
B. Safety temperature limiters need only be checked on special circumstancesC. Pressure limiters if they are not preceded by safety valves of a special design
devices.D. If necessary, temperature and pressure controllers are tested by pressing the by-
passing push buttonE. Seals, locks and packingsF. Shaft bearing (noise and heat development)G. Stand by feed pumps and oil pumps etc. must be started-up briefly/valves must be
switched over.H. Firing parts, flame monitors
Semi-annual Checks
Controllers and safety devices must be serviced and checked by a technically competent person after every
period of 6 months. We recommend our customer service for this purpose.
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Operating Logbook for Aux. Steam Boiler
Operating Logbook for Aux. Steam Boiler
36
Operating Instruction for Aux. Steam Boiler
VI. Boiler Operation Water Treatment
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Phosphate Dosing System Line
Hydrazine & Amine Dosing System Line Feed Water Sample Line
38
Blow Down System Line & Boiler Sample Line
Origin of the Problem
Source of corrosion :Dissolved gas: oxygen, carbon dioxide, and ammonia. Oxygen is the most aggressive.Cause pitting corrosion
• Make-up water introduces soluble oxygen.• The condensate return system contains soluble
oxygen
The water quality control system required shall be controlled by hydrazine & neutralizing amine which supplied by chemical dosing system consist of injection pumps, dosing tanks & motorized agitator
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Boiler Waterside Corrosion
Contributors: dissolved oxygen, acid or caustic in the water and a high temperature. Cause severe pitting, gouging and embrittlementFAILURE
Water will rapidly corrode mild steel; as the temperature increases, the reaction accelerates.
Reaction :
Anode : Fe Fe2+ + 2e-
Cathode: 1/2O2 + H2O + 2e- 2OH-
Overall: Fe + 1/2O2 + H2O Fe (OH)2
Boiler deposits result from hardness salts, metallic oxides, silica and a number of other feed water contaminants that can enter the system. Minimizing the adverse impact of these contaminants is the role of the boiler water treatment program.
Even the best controlled systems occasionally have upsets that cause excessive amounts of contamination to pass into the boiler. Some examples would be:
• Excess leakage from an ion exchange system• Contamination from leakage into condensate systems• Inadequate steam condensate protection programs resulting in high levels of
corrosion products returning to the boiler
An internal boiler water treatment program must be forgiving enough to handle not only normal operating conditions but periodic upsets as well.
Waterside Deposition
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Mechanism of Deposition
“More deposit will decrease Boiler
efficiency and subject to overheating”
• Reaction:10Ca2+ + 6PO43- + 2OH- 3Ca3(PO4)2·Ca(OH)2 Calcium hydroxyapatite
3Mg2- + 2SiO32- + 2OH- + H2O 2MgSiO3Mg(OH)2H2O Serpentine
A Partial List of Boiler Deposits
5CaO·5SiO2·H2OXonotlite
CaSiO3Wallastonite
Na2SO4Thenardite
3MgO·2SiO2·2H2OSerpentine
SiO2Alpha-Quartz
Na2O·4CaO·6SiO2·H2OPectolite
4Na2O·3Al2O3·6SiO2·SO4Noselite
Fe3O4Magnetite
Ca10(OH)2(PO4)6Hydroxyapatite
Fe2O3Hematite
4Na2O·CaO·4Al2O3·2CO2·9SiO2·3H2OCancrin
CaCO3Calcite
Mg(OH)2Brucite
CaCO3Aragonite
CaSO4Anhydrite
Na2O·Al2O3·4SiO2·2H2OAnalcite
Na2O·Fe2O3·4SiO2Acmite
FormulaName
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Embrittlement
Caustic embrittlement or intercrystalline cracking
Undetectable during operating conditions
Catastrophic results
Causes:1. Leakage of boiler water 2. Concentrated caustic soda occurs from the concentrated boiler
water.3. There is high metal stress in the area of caustic concentration and
leakage.
External TreatmentTo improve the quality of this source prior to its use as boiler feed water, including reducing contaminants.
Applied to water prepared for use as boiler feed water, refers to the chemical and mechanical treatment of the water source.
External treatment normally includes: Clarification, Filtration, Softening, Dealkalization, Demineralization, Deaeration, Heating
Internal Treatment
To minimize impurities after the best and most appropriate external treatment of the water source, boiler feed water (including return condensate)
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Steam Plant Operation- Feed Water Preparation
Deaerate the feedwaterBy using a deaerator and adding oxygen scavengers (Hydrazine) in the feed water tank.
Minimize hardnessEx : Calcium and Magnesium, migratory iron, migratory copper, colloidal silica, consistent with boiler design and operation parameters.
Minimize corrosive gasesEx : Dissolved oxygen and dissolved carbon dioxideThe deposition of these metallic oxides in the boiler is frequently more troublesome than the actual damage caused by the corrosion.
Deaeration (Mechanical and Chemical)
Mechanical and chemical deaeration is an integral part of modern boiler water protection and control.
Objectives :
• To remove oxygen, carbon dioxide and other non-condensable gases from feed water
• To heat the incoming makeup water and return condensate to an optimum temperature
• Minimizing solubility of the undesirable gases
• Providing the highest temperature water for injection to the boiler, from ambient temperature to 103 ºC to prevent boiler from thermal shock
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Saturated steam (1243 kg/hr, temperature 105-180 ºC, pressure 9 bar (g) )The dissolved oxygen leaving the deaerator will be ± 7 ppb to protect auxiliary boiler system from corrosion with residual hydrazine approximate 0.1 ppm.
Deaeration (Mechanical and Chemical)
• Designed to minimize saturated dissolved O2content in the supplied de-mineralized water and to achieve a suitable O2 content fed to the boiler
Deaerating Heater Troubleshooting Guide
1. Check for improper operation of steam pressure reducing valve.Low pressure
3. Check relief valves on the deaerator and in the main steam supply system for proper operation.
2. Check faulty operation of steam pressure reducing valve.
1. Improper operation of inlet control valve. Adjust as necessary.
High or low water level
2. Condensate may be too hot. Water entering the deaerating heater must usually be cooled if the temperature is within 20 º F of saturation temperature of the steam. Check the design specification to determine what inlet water temperature was originallyintended.
1. Trays collapsed-possibly from interrupted steam supply or sudden supply of cold water causing a vacuum.
Excessive consumption of oxygen scavenger
2. Excessive free air due to leaking stuffing boxes on pumps upstream of deaerator that have negative suction head. Repair stuffing box or seal with deaerated water.
1. Improper spray from spray nozzle. Check nozzle for sediment or deposit on seat or broken spring.
Temperature in storage tank does not correspond within 3 º C of saturation temperature of the steam
3. Check water and, if possible, steam flow rates vs. design. Trays or scrubber and inlet valves are designed for specific flow ranges.
2. Check steam pressure reducing valve. Check valve for free operation, and see that control line is connected to the connection provided in the deaerator.
1. Insufficient venting-increase vent rate by opening the manually operated air vent valve.
Excessive oxygen content in deaerator effluent
RemedySymptom
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Effect of pH on the Corrosion Rate of Steel. Water Chemistry Upsets Result in
Decrease or Increase of pH of Boiler Water, Resulting in Tube Deposits or
Corrosion.
Rel
ativ
e C
orro
sion
Rat
e
ppm HCl ppm NaOH
40.4
3650 365 36.5 200 00040 0004 0004000 403.60.36
approximate pH141211102 6345 7
9
The Effect of pH On Corrosion Rate
The slowest corrosion rate In Boiler Water are in
9.5 - 11
Mineral Carryover
Effects:1. Deposition in regulators and valving2. Deposition in superheaters3. Deposition in control valves and turbines4. Process contamination
Definition:Carryover is generally considered to be any contaminant that leaves a boiler steam drum with the steam.
Causes:Mechanical Factor: Priming (sudden pressure while load rises)Chemical Factor: Foaming (by alkalinity, organic and synthetics contaminant), Selective vaporous carryover
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Characteristics:Reaction:CO2 + H2O H2CO3
H2CO3 H+ + HCO3-
Cause pH drop and grooving on metal surface
Carbon dioxide CorrosionSource:
Alkalinity in feed waterHCO3
CO3 heat CO2
Air in- leakageOrganic material
Caustic Corrosion
Characteristics :Often occurs in High Pressure BoilerLocalized corrosionContributed by deposit accumulation (Iron, copper, etc)Boiler operation excess maximum capacityMassive load fluctuation
Reactions :Fe2O3 + 2NaOH 2NaFeO2 + H2OFeO + 2NaOH Na2FeO2 + H2OFe +2NaOH + 2H2O 2NaFeO2 + H2O
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Internal Boiler Water Treatment
10Ca2+ + 6PO43- + 2OH- 3Ca3+(PO4)2·Ca(OH)2 [Calcium hydroxyapatite]
3Mg2- + 2SiO32- + 2OH- + H2O 2MgSiO3Mg(OH)2H2O [Serpentine]
Use internal conventional program : • Hydrazine
Magnetite build upN2H4 + 6Fe2O3 4Fe3O4 + N2 + H2O
• Phosphate, An anti-scale agent 3Ca(HCO3)2 + 2Na3PO4 Ca3(PO4)2 + 3Na2CO3 + 3CO2
Thermally unstableCorrosive volatile gas
Sludge
• Neutralizing Amine, Removing acid NH3 + CO2 + H2O NH4+ + HCO3-
R-NH2 + CO2 + H2O R-NH3+ + HCO3-
R-ONH + CO2 + H2O R-ONH2+ + HCO3-
Corrosion Control Programs
The basic approach to chemical treatment of condensate systems is through the use of Hydrazine, Phosphate Program, Neutralizing Amine, combinations of both amines and hydrazine.
REAKSI HYDRAZINEOxygen scavenging,N2H4 + O2 N2 + 2 H2O
Stochiometric reaction,dosage of 35 % solution – 8.6 ppm/1 ppm residual oxygen
Poisonous, LD50 rating – class 5 toxin – 82 mg/kg
Magnetite build up,N2H4 + 6Fe2O3 4Fe3O4 + N2 + H2O
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Function: To neutralize the carbon dioxide and then provide small additional amounts to buffer the pH to 8.5 or 9.5.
Neutralizing Amines
Neutralizing carbonic acidNH3 + CO2 + H2O NH4+ + HCO3-
R-NH2 + CO2 + H2O R-NH3++ HCO3-
R-ONH + CO2 + H2O R-ONH2+ + HCO3-
WATER SPECIMENT
• Boiler and feed water must be checked daily. At least the boiler water should be sampled by means of a sample cooler. If there is a possibility of feed water hardness, it is also necessary to check the hardness of the feed water everyday.
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Spec. conductivity : < 1.0 uscmSilica: : < 0.02 ppm SiO2pH: : 6.5 ~ 7.5Sodium: : < 0.005 ppm NaIron : 0.02 ppm Fe
1. Demin Water Outlet
QUALITY WATER PARAMETER
Spec. conductivity : < 5.0 us/cm at 25 deg.CSilica : < 0.02 ppm SiO2pH : 8.5 ~ 9.5Hydrazine : < 0.2 ppm N2H4Iron : <0.02 ppm Fe
2. Boiler Feed Water
Spec. Conductivity: < 150.0 us/cm at 25 deg.CSilica : < 2 ppm SiO2pH : 9.5 ~ 10.5Phosphate : 3.0 ~ 10. ppm PO4
3. Boiler Water
Spec. Conductivity: < 5.0 us/cm at 25 deg.CSilica : < 0.02 ppm SiO2pH : 8.5 ~ 9.5Iron : <0.02 ppm Fe
4. Steam
Blow down Definition
Function:To maintain the solids content of the boiler water within prescribed limits
Basic Calculation % Blow down : Concentration of dissolved solids in Feed water =Concentration of dissolved solids in blowdownQuantity of blow down/Feed water% Make up : Concentration of dissolved solids in Feed water =Concentration of dissolved solids in Make-up water Quantity of make–up/ Feed water
Every steam generator must be blow down periodically (recommended every two hours, at least every one shift). The quantity of blow down water depends on the degree of thickening. If no desalting fitting is provided, blowing down simultaneously extracts salt from the boiler
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CR = 1/%blowdown x 100 =
Concentration dissolved solids of blowdownConcentration dissolved solids of Feed water
Feed water = Make up + CondensateFeed water = Boiler Capacity + Blow down
• Do open blow down if the quality of water excess limit : Demin Water Boiler Water
Blow down in Action
Spec. conductivity : > 10 uscmSilica: : > 0.02 ppm SiO2pH: : <6.5 or > 8
Spec. conductivity : > 150 uscmSilica: : > 2 ppm SiO2pH: : > 10.5
WATER SIDE CONSERVATIONPurpose
The greatest danger to steam boilers is today the uncontrolled absorption of atmospheric oxygen by the boiler water during shut down periods.
Oxygen has a corrosive effect – particularly during start-up, but also during shut down periods.
Method
1. Wet conservation binds the oxygen of the water held in the boiler. oxygen binding agents are: Hydrazine & Sodium sulphite
2. Dry conservation ensures that no moisture remains in the boiler effectively preventing corrosion of the steel
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HYDRAZINE WET CONSERVATION PROCEDURE1 g (atmospheric) oxygen in the water is bound by 1 g hydrazine (N2H4) = 7 g commercial, approx. 24% hydrazine hydrate (N2H4.H2O)
1000 - 3000150 - 450Boilers with alkalinization and only softened feed water irrespective of time
140-210350 – 700700 - 2000
20 - 3050 – 100100- 350
≤ 50 h (weekend)1 monthlonger
Boilers with alkalinization and fully demineralized feed water
g/m3g/m3
N2H4.H2O 24%N2H4Hydrazine excess based on the length of the rest period
The additionally required hydrazine excess is shown in the table:
HYDRAZINE WET CONSERVATION PROCEDUREa, In glass vessels, pure hydrazine reacts only above 60°C with oxygen dissolved in water.
the Fe3O4 of the protective layer is an excellent catalyst.
b. Wet conservation the pH-value of the hydrazine-containing solution should be 10 or higher.
c. To prevent varying oxygen concentration and therefore the creation of air entrainment elements, the steam boiler must be completely filled with hydrazine-containing boiler water.
d. All gate – and screwdown stop valves must be closed completely after filling the boiler withhydrazine-containing boiler water and kept closed during the conservation treatment.
e. If within the shut down period the hydrazine concentration must be topped up. Circulate the boiler water to ensure through mixing.
f. When the boiler is restarted, the water level is reduced to normal provided that higher N2H4contents in the initial steam are acceptable.
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SODIUM SULPHITE WET CONSERVATION PROCEDURE
1 g (atmospheric) oxygen in the water is bound by 9 g commercial, approx. 92% moisture-free, sodium sulphite (Na2SO3)
The additionally necessary sodium sulphite excess is shown in the table:
1500 - 5000Boiler with alkalinization and only softened feed water independent of time
g /m3200-300450 – 900900 - 3000
Boiler with alkalinization and fully demineralized feed water ≤50 h (week end)1 monthlonger
Na2SO3 92%Sodium sulphite excess based on the length of the shut down period
SODIUM SULPHITE WET CONSERVATION PROCEDURE
a. Powdered sodium sulphite must be dissolved in warm feed water at 30-40°C before filling it into boiler. (Per 1 kg sodium sulphite 5 liters water).
b. In the case of wet conservation the pH value of the sodium sulphite – containing solution should be at 10 or higher. Apart from caustic soda and phosphate, as present in the boiler water and sufficient for alkalinization, an extra addition of ammonia may also be successful
c. To exclude different oxygen content and therefore the formation of the air entrainment elements, the steam boiler must be completely filled with sodium sulphite containing boiler water. In superheaters or feed water preheater the sodium sulphite containing.
d. All gate and screw down stop valves must be closed after the boiler has been filled with sodium sulphite containing boiler water and kept closed during the conservation treatment.
d. If within the shutdown period the sodium sulphite excess drops below 500 g/m3, the sodium sulphite concentration must be topped up.
e. Before restarting the boiler, the boiler water condition must be adjusted to the specified values (pH-value, sodium sulphite content)
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Test Procedure Wet Conservation
Testing for excess of oxygen binding agent in the case if wet conservation
• Purpose
i. Hydrazine measurement
Hydrazine forms in an acid solution with p-dimethylaminobenzaldehyde, depending on concentration, a yellow to red colored quinoid compound for color comparison
• Reagents
Sulphuric 2% p-dimethylaminobenzaldehyde solution Colour comparison ampoules (Both available from Farbenfabriken Bayer AG, Leverkusen, Germany, or their agents)
• Procedure
1. The water sample to be tested for hydrazine content must first be cooled to < 40°C (sampling is best carried out with a cooling agreement). The boiler water may first have to be filtered.
2. 5 ml of this water sample is filled up to the first calibration mark into the empty ampoule, 5 ml hydrazine reagent is filled in to reach the second calibration mark, and then shaken twice. The test liquid will turn yellow. Now the reference ampoule or color comparison sheet nearest to this color shade is determined. The value shown on this ampoule or the sheet indicates the hydrazine (N2H4) content in kg/l of the water sample.
3. If the test liquid shows yellow color shades which are not covered by the comparison scale, the N2H4 – content is situated above 1 mg/l. These values, too, can be determined more accurately by first diluting 1 ml of the water to be tested with 99 ml cold tap water, mixing 5 ml of this diluted water with 5 ml reagent and comparing against the color scale. The value found must then depending on the dilution used – be multiplied by 100.
4. The reagent must always be stored in a dark and cool place. Storage life approximately 1 year (see use-by date printed on the label). The effectiveness of the reagent solution can be verified at any time by mixing 5 ml tap water with 5 ml reagent, after which there must be, no coloration exceeding the zero value of the color scale.
Test Procedure Wet Conservation
53
ii. Sulphite measurement
The process is intended to provide a simple check of the addition of sodium sulphitenecessary to bind the oxygen in the boiler water
In an acid solution, iodine oxidizes sulphite to sulphate and is then itself reduced to iodide. Excess iodine produces a blue coloration in combination with starch solution. Nitrites, sulphides and larger quantities of organic substances have an interfering effect (KMnO4 –consumption over 60 mg/l)
• Reagents
Phosphoric acid D.1.14 (25%)0.01 standard iodine solution (Store in a cool place in a brown bottle)Starch solution, approx. 1%
• Instruments300 ml Erlenmeyer flask10 ml graduated pipette20 ml burette, 0.1 ml graduation
Test Procedure Wet Conservation
• Procedure
1. 100 ml of the sample, cooled to room temperature and filtered clear is filled into a 300 ml Erlenmeyer flask and acidified with 3 ml phosphoric acid (reagent a)
2. After that, add approx. 0.5 to 1 ml of the starch solution (reagent c)
3. Using a burette, 0.01 standard iodine solutions (reagent b) is now added until the sample turns blue.
4. 1 ml 0.01 standard iodine solution corresponds when using 100 ml sample solution to approx. 6.3 mg/l sodium sulphite (Na2SO3)
Quick testSmall test sticks can be used for a quick determination of the sulphite content (e.g. Sulphite Test made by Fa.Merck)
Test Procedure Wet Conservation
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Alkaline Boiling Out Procedure
Alkaline boiling is carried out to removal of oils, fat and silica in newly installed boilers, and drying the heat insulating material of boilers.
• Purpose
• Applicable ItemAuxiliary Boiler BHS-12000-LO
• Measurement Equipment & Safety Equipment
Balance : 1 unitHand Pump : 1 unitRubber gloves : 4 pairMasker : 4 pairpH meter : 1 unit
Sodium hydroxide 100 kgSodium Phosphate 200 kgSodium Sulfite 60 kg
• Consumable Material
1. Mixing of the Chemical
• Fill the demineralized water to the Feed Water Tank approximate ½ of volume (6 m3)
• Prepare 7.2 kg Sodium Sulfite, 24 kg Sodium Phosphate & Sodium Hydroxide 12 kg
• Fill the phosphate dosing tank with 500 liter Demineralized Water.
• Slowly through the 1.2 kg Sodium Sulfite, 4 kg Sodium Phosphate and 2 kg of sodium hydroxide to the phosphate tank than turn on the mixer approximate 15 minutes. Measured the pH
• Transfer the mixing solution to Feed Water Tank by Hand Transfer pump. Measured the pH of the solution in the feed water tank. The pH of the feed water tank < 11.5 but higher than 10.5
• Application
Alkaline Boiling Out Procedure
55
• Turn on The feed water pump to transfer the solution to the boiler
• Now the solution in the boiler will be approximate ½ of volume of the Boiler.
• Open the valves on feed water line to full fill the solution at feed water line the solution to the boiler.
• Repeat point a to h until the boiler is full of the solution.
• Repeat point b to point e for six times.
2. Closed all the valves attached in the boiler
3. Turn on the burner and heating the boiler until the temperature of mixing solution is 140 °C – 145 °C or boiler pressure 2.5 bar(g) – 3 bar(g). The rate of the heating of the boiler must not exceed about 50 °C per hour by adjusting the burner combustion rate.
4. Maintain the temperature 140 °C – 145 °C or boiler pressure 2.5 bar(g) – 3 bar(g) for 4 hours than cool down the boiler by ambient temperature. The cooling rate must not exceed 50 °C per hour.
Alkaline Boiling Out Procedure
5. While maintain the temperature or pressure, prepare the solution as per point
6. After the boiler temperature is about 70 °C than slowly drained the solution up to ¾ solution level of the boiler while take the solution sample foranalyzing than feeding the new solution to the boiler. The concentration of the cleaning agents while draining & feeding must not fall below ½ of the initial level.
7. After the boiler water have been drained approximate ¾ the volume of the boiler, or the Feed Water Tank have transfer the solution approximate 12 m3, than closed the drained valve, repeat the point j to full fill the boiler with the solution again.
8. Repeat the point 2 – point 8 for 2 times.
9. Drain out all the water in the boiler and make a new solution to the Feed Water tank same as point 1 but the pH < 9.5 but not less than 8.5. than full fill the boiler with this solution. If the boiler ready to run the water level of this solution shall be at the normal level.
Alkaline Boiling Out Procedure
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THE END