anal&samp(h2 in cl2, co,co2,methane)
DESCRIPTION
analysersTRANSCRIPT
1Analysers & Sampling Systems
TOPICS
I HYDROGEN IN CHLORINE ANALYSER
• PURPOSE OF ANALYSIS
• SELECTION OF ANALYSER
• ANALYSER -WORKING PRINCIPLE
• SAMPLE HANDLING SYSTEM
• CALIBRATION
• TROUBLE SHOOTING
2Analysers & Sampling Systems
TOPICS
II CO,CO2 & METHANE ANALYSER
• PURPOSE OF ANALYSIS
• SELECTION OF ANALYSER
• ANALYSER -WORKING PRINCIPLE
• SAMPLE HANDLING SYSTEM
• CALIBRATION
3Analysers & Sampling Systems
CAUSTIC / CHLORINE PLANTS
• HYDROGEN IN CHLORINE ANALYSER
• PURPOSE OF ANALYSIS
• SAFETY OF THE PLANT
4Analysers & Sampling Systems
COMPOSITION
SR. NO. COMPONENT MIN. %V/V NOR. %V/V MAX. %V/V
1 CHLORINE 85 94 97
2 HYDROGEN 1.4 1.00 0.2
3 OXYGEN 2.73 0.964 0.564
4CARBONDIOXIDE
0.541 0.191 0.112
5 NITROGEN 10.27 3.627 2.12
6 MOISTURE 0.059 0.004 0.01
5Analysers & Sampling Systems
SELECTION OF ANALYSERS
• IF THE PURPOSE IS TO MEASURE ONE COMPONENT IN THE PRESENCE
ANOTHER ,IT IS NECESSARY THEN TO LOOK FOR THE UNIQUE PROPERTY
OF THE MATERIAL TO BE MEASURED.
6Analysers & Sampling Systems
SELECTION OF ANALYSER
• UNIQUE PROPERTY OF THE COMPONENT
• THERMAL CONDUCTIVITY
7Analysers & Sampling Systems
SELECTION OF ANALYSER
• ALTERNATE METHOD OF ANALYSIS
• LAB METHOD
ORSAT APPARATUS
NaOH + Cl2 N a C l + H2O
8Analysers & Sampling Systems
THERMAL CONDUCTIVITY• DIFFERENT COMPONENTS
GASES TC factor
Cl2 0.381
H2 6.990
O2 1.052
CO2 0.690
N2 0.996
CO 0.962
SO2 0.377
9Analysers & Sampling Systems
THERMAL CONDUCTIVITY
• SAMPLE
REFERENCE
10Analysers & Sampling Systems
THERMAL CONDUCTIVITY DETECTOR
• TYPES OF FILAMENTS
1 METALLIC WIRES - TUNGSTEN ,NICKEL,PLATINUM
ADVANTAGES:
HIGHER TEMPERATURE
LINEAR OVER A WIDE RANGE
SIMPLE CONSTRUCTION
2 THERMISTOR
ADVANTAGES:
AMBIENT TEMPERATURE
VERY GOOD SENSITIVITY
11Analysers & Sampling Systems
MEASURING CELL
12Analysers & Sampling Systems
REFERENCE GAS
• FLOWING REFERENCE
USED FOR SPECIAL TASKS
• STATIONARY (SEALED) REFERENCE GAS
H2 , AIR , SO2 etc ARE USED
13Analysers & Sampling Systems
MEASURING CELL CASE - PURGING
14Analysers & Sampling Systems
H2 IN Cl2 ANALYSER
» SAMPLE HANDLING SYSTEM
• SAMPLE TAKE-OFF POINT
GAS SAMPLE
• SAMPLE TRANSPORT
TYPE - A SINGLE LINE WITH BYPASS STREAM
• SAMPLE CONDITIONING
• SAMPLE DISPOSAL
15Analysers & Sampling Systems
H2 IN Cl2 ANALYSER
… SAMPLE CONDITIONING
• PHYSICAL PROPERTIES
PRESSURE CONTROL
FLOW CONTROL
TEMPERATURE CONTROL
16Analysers & Sampling Systems
AUXILLIARY REACTION
• PURPOSE
1. IMPROVE DETECTABILITY OF THE COMPONENT OF INTEREST
2. ELIMINATE THE EFFECT OF GASES THAT LEAD TO INCORRECT RESULTS
17Analysers & Sampling Systems
CHEMICAL REACTION ( AUXILLIARY REACTION )
UV RADIATION• H2 + C l 2 2HCl
• UV SOURCE - LOW PRESSURE MERCURY VAPOUR LAMP
WAVELENGTH - 254 nm
POWER - 150 m W
• REACTION TUBE - QUARTZ
THERMAL CONDUCTIVITY OF 2HCl = CL2
18Analysers & Sampling Systems
UV REACTION ATTACHMENT
• CASE MATERIAL - FIBRE REINFORCED POLYESTER
• TUBING MATERIAL - VITON
• DOUBLE WALLED QUARTZ WITH REFLECTOR
1 OPTIMUM UTILISATION OF UV RADIATION
2 EYE PROTECTION FOR THE OPERATOR
• PURGING WITH AIR
1 AVOID INGRESS OF AGGRESSIVE GASES
2 REMOVE ANY FORMED OZONE
19Analysers & Sampling Systems
UV REACTION ATTACHMENT
• CASE MATERIAL - FIBRE REINFORCED POLYESTER
20Analysers & Sampling Systems
UV REACTION ATTACHMENT
21Analysers & Sampling Systems
COMPOSITION
SR. NO. COMPONENT MIN. %V/V NOR. %V/V MAX. %V/V
1 CHLORINE 3.83 6.61 7.19
2 HYDROGEN 2.03 3.5 3.8
3 OXYGEN 19.68 18.72 18.53
4CARBONDIOXIDE
0.41 0.71 0.76
5 NITROGEN 74.04 70.45 69.71
6 MOISTURE 0.01 0.01 0.01
22Analysers & Sampling Systems
TUBULAR FURNACE
• SAMPLE GAS COMPOSITION
Cl2 < 20 % V/V
• FURNACE - TEMP. 800 deg. C
23Analysers & Sampling Systems
MEASUREMENT
UV Reaction
Thermal conductivit Analyser
Cl2, H2, O2, CO2 etc Vent
Sample in
Cl2, H2, O2, CO2 etc
Analyser output H2 concentration
HCl, O2, CO2 etc
24Analysers & Sampling Systems
MEASUREMENT
• FROM REACTION ATTACHMENT
SAMPLE GAS MINUS HYDROGEN
• DIFFERENCE IN THERMAL CONDUCTIVITY
HYDROGEN CONCENTRATION
25Analysers & Sampling Systems
H2 IN Cl2 ANALYSER
… SAMPLE CONDITIONING• PRESSURE CONTROL
SAMPLE STREAM PRESSURE - 2.5 BAR
OPERATING PRESSURE FOR ANALYSER - 0.36 - 1.45 PSI
(0.02 - 0.099 BAR)• FLOW CONTROL
SAMPLE STREAM FLOWRATE -
FLOWRATE FOR ANALYSER - 30 - 60 L/HR
• TEMPERATURE CONTROL
SAMPLE STREAM TEMPERATURE - - 39deg C
TEMPERATURE FOR ANALYSER - 5 - 50 deg C
26Analysers & Sampling Systems
H2 IN Cl2 ANALYSER
• SAMPLE CONDITIONING
• REMOVAL OF OTHER COMPONENTS
- FILTER
- DRIER
27Analysers & Sampling Systems
SAMPLING SYSTEM
28Analysers & Sampling Systems
SAMPLE DISPOSAL
• BACK PRESSURE SENSITIVE - ANALYSER
LIMITS - 150 mmWC to 50 mmWC • VENTS
BYPASS STREAM & ANALYSER VENT
SEPARATE LINES
• RELEASING TO ATMOSPHERE
VENDOR PREFERENCE
• STATUATORY REQUIREMENT
TREATMENT BEFORE DISPOSAL
WASTE AIR HEADER - BLEACH LYE UNIT
29Analysers & Sampling Systems
SAMPLE DISPOSAL
•
VENT
WASTE AIR HEADER
• PROVIDE LIQUID SEAL
30Analysers & Sampling Systems
ENCLOSURE
• CABINET MOUNTING
ANALYSER & SAMPLE HANDLING SYSTEM
• PURGING OF PANEL
CORROSSIVE ATMOSPHERE
31Analysers & Sampling Systems
CALIBRATION OF ANALYSER
• PRIMARY CALIBRATION
BY ACTUAL COMPOSITION - MIN , NOR & MAX
CALIBRATION GRAPH - EMBEDDED IN MICRO-PROCESSOR
• SECONDARY CALIBRATION - SPAN GAS
CALIBRATION GAS - H2 IN N2
FREQUENCY OF CALIBRATION - ONCE IN AWEEK
• ZERO GAS
PURE N2
32Analysers & Sampling Systems
ATTENTION
• FeCl2 FORMATION DURING START UP
FILTER CHOCKING¤ REMEDY
SAMPLE LINE SHALL SLOPE UP FIRST
PROVIDE A DRAIN AT THE LOWEST POINT
• CHLORINE LEAK
¤ SEPARATE OUT SAMPLE HANDLING AND ANALYSER MOUNTING¤ PROVIDE CHLORINE DETECTORS IN THE CABINET¤ ISOLATE THE INLET AND OUTLET LINES AUTOMATICALLY¤ FLOWSWITCHES ON SAMPLE , REFERENCE& VENT LINES. WIRE THEM
TO MONITORING SYSTEM
• MERCURY VAPOUR LAMP
LIFE - 10-12 MONTHS
33Analysers & Sampling Systems
GASIFIER UNIT
• CO2 ,CO & CH4 ANALYSIS
• PURPOSE OF ANALYSIS
• QUALITY OF THE PRODUCT
34Analysers & Sampling Systems
COMPOSITION
SR.NO COMPONENT MIN. NOR. % MAX.
1 CO 22.89
2 CO2 2.27
3 H2 22.93
4 COS 0.002
5 CH4 0.2
6 N2 0.118
7 Ar 0.183
8 H2O 51.23
9 H2S 0.08
10 NH3 0.069
35Analysers & Sampling Systems
GASIFICATION PROCESS BY TEXACO
• SYNTHESIS GAS (CO , H2)
Partial oxidation
2 C n H m + n O2 2n CO + m H2
( Moderator )
Partial oxidation - 1290 0 c - 1400 0 c
Complete oxidation > 1400 0 c
Water gas shift reaction:
2 C n H m + n H2O 2n CO + (m+2n) H2
36Analysers & Sampling Systems
GASIFICATION PROCESS BY TEXACO
• SYNTHESIS GAS (CO , H2)
Crack Reaction :
C m H n n / 4 CH 4 + m - n / 4 C
Water gas shift equilibrium:
CO + H2O CO2 + H2
37Analysers & Sampling Systems
SELECTION OF ANALYSER
• PROPERTY OF THE COMPONENTS
¤ THERMAL CONDUCTIVITY
¤ ABSORPTION OF IR RADIATION
38Analysers & Sampling Systems
SELECTION OF ANALYSER
• THERMAL CONDUCTIVITY
39Analysers & Sampling Systems
PHOTOMETRY ( SPECTROMETRY)
IT IS THE QUANTITIVE MEASUREMENT OF CONCENTRATION OF A
SUBSTANCE BASED UPON THE PROPERTY OF SUBSTANCE FOR ABSORBING
ELECTRO MAGNETIC RADIATION & EXISTANCE OF A METHOD FOR THE
MEASUREMENT OF THE QUANTITY OF RADIATION ABSORBED.
40Analysers & Sampling Systems
PHOTOMETRY
BEER - LAMBERT LAW
A = b c
A - Absorbance
- Molar Absorptivity
b - Thickness of the light absorbing medium
c - Concentration of the Absorbing species
41Analysers & Sampling Systems
PHOTOMETRY
BEER - LAMBERT LAW
In the Process Stream ;
A = 1 b c1 +2 b c2 +3 b c3 + …….
A - Absorbance
1 2 3 - Molar Absorptivities
b - Thickness of the light absorbing medium
c1 2 3 - Concentrations of the Absorbing species
Remedy : Measurement & reference wave lengths
42Analysers & Sampling Systems
PHOTOMETRY
• INFRARED PHOTOMETRY
• ULTROVIOLET & VISIBLE PHOMETRY
IR - Vibrational & rotational motion of molecules
- Fundamental frequency
UV & Visible - Excitation of electrons
43Analysers & Sampling Systems
COMPONENTS
• SOURCE
• MONOCHROMATOR
• SAMPLE CELL
• DETECTOR
• TRANSMITTER
44Analysers & Sampling Systems
SOURCE
• SOURCE
IR RADIATION : Heat
Sources : Quarts Iodine Lamp
Tungsten Filament
Nichrome wire
45Analysers & Sampling Systems
MONOCHROMATOR
• DISPERSIVE TYPE : Prism
Breaks the electromagnetic spectrum into separate wavelengths
• NON -DISPERSIVE TYPE (NDIR) : Interference filter
Excludes all but few bands of radiation by destructive interference.
46Analysers & Sampling Systems
SAMPLE CELL
• The Component which brings the conditioned sample to the optical path of the Instrument.
CELL BODY - Extn of sample Conditioning
system
CELL WINDOWS - Part of optical system
SAMPLE CELL
47Analysers & Sampling Systems
DETECTORS • Thermocouple
• Luft / Microphone
• Micro-flow Sensor
• Pyro- electric
48Analysers & Sampling Systems
LUFT / MICROPHONE
• Capacitance change
• Double beam
49Analysers & Sampling Systems
MICRO- FLOW
• Change in flow
• Double beam
50Analysers & Sampling Systems
PHOTO METRIC ANALYSER GEOMETRY
SINGLE BEAM IN SPACE
• SINGLE BEAM
SINGLE BEAM IN TIME
DOBLE BEAM IN SPACE
• DOUBLE BEAM
DOUBLE BEAM IN TIME
51Analysers & Sampling Systems
PHOTO METRIC ANALYSER
• REFERENCE WAVE LENGTH
• MEASUREMENT WAVE LENGTH
52Analysers & Sampling Systems
PHOTO METRIC ANALYSER GEOMETRY
• SINGLE BEAM IN SPACE
53Analysers & Sampling Systems
PHOTO METRIC ANALYSER GEOMETRY
• SINGLE BEAM IN TIME
54Analysers & Sampling Systems
PHOTO METRIC ANALYSER GEOMETRY
• DOBLE BEAM IN SPACE
55Analysers & Sampling Systems
PHOTO METRIC ANALYSER GEOMETRY
• DOUBLE BEAM IN TIME
56Analysers & Sampling Systems
MEASUREMENT
A = log ( I0 / I ) = b c
I0 - Radiation intensity entering the sample
I - Radiation intensity leaving the sample
A - Absorbance
- Molar Absorptivity
b – sample path length
c – absorber concentration
57Analysers & Sampling Systems
MULTICOMPONENT ANALYSER
… SAMPLE CONDITIONING• PRESSURE CONTROL
SAMPLE STREAM PRESSURE - 79 . 4 BAR G
OPERATING PRESSURE FOR ANALYSER - 16 -250 hPa
(0.016 - 0.25 BAR)• FLOW CONTROL
SAMPLE STREAM FLOWRATE -
FLOWRATE FOR ANALYSER - 10 -100 L/HR
• TEMPERATURE CONTROL
SAMPLE STREAM TEMPERATURE - 245 deg C
TEMPERATURE FOR ANALYSER - 0 to 45 deg C
MEASURING CHAMBER IS MAINTAINED AT A TEMPERATURE ABOVE AMBIENT.
58Analysers & Sampling Systems
REFERENCE GAS
• STATIONARY (SEALED) REFERENCE GAS
• INERT GAS FILLED ( N2)
59Analysers & Sampling Systems
MULTICOMPONENT ANALYSER
• SAMPLE CONDITIONING
• REMOVAL OF OTHER COMPONENTS
- MOISTURE
- DUST / SOLID PARTICLES
60Analysers & Sampling Systems
SAMPLE CONDITIONING
•
61Analysers & Sampling Systems
ENCLOSURE
• ANALYSER HOUSE
ANALYSER
SAMPLE HANDLING SYSTEM
• VENTILLATION FOR THE ANLYSER HOUSE
INTERNAL HAZARD
• CO DETECTORS
62Analysers & Sampling Systems
CALIBRATION OF ANALYSER
• CALIBRATION - SPAN GAS
CO /CO2/CH4 IN N2 CALIBRATION GAS
FREQUENCY OF CALIBRATION - EVERY SHIFT
• ZERO GAS
PURE N2
63Analysers & Sampling Systems
SAMPLE DISPOSAL
• BACK PRESSURE SENSITIVE - ANALYSER
LIMITS - 1300 hPa (1.3 BAR)
• VENTS
BYPASS STREAM & ANALYSER VENT
SEPARATE LINES
• RELEASING TO ATMOSPHERE ?
64Analysers & Sampling Systems
REFERENCES
• ON-LINE PROCESS STREAM ANALYSERS - SHELL GROUP :1970
• PROCESS ANALYSERS - API 555: 1995
• SAMPLING SYSTEM FOR PROCESS ANALYSERS - D.C.CORNISH
• ON-LINE PROCESS ANALYSERS - GARY D. NICHOLS
• INSTRUMENTATION &CONTROL ( VOL2 - ISSUE 1)
• ON-LINE PROCESS ANALYSERS - D.J.HUSKINS
65Analysers & Sampling Systems
FLOW VELOCITIES
• TYPICAL FLOW VELOCITIES ARE
5 TO 10 FEET/SECOND FOR LIQUIDS
20 TO 40 FEET/SECOND FOR GASES