Оглавление
Tony Waters. Process Gas Chromatographs
Table of Contents
List of Tables
List of Illustrations
Guide
Pages
Process Gas Chromatographs Fundamentals, Design and Implementation. Fundamentals, Design and Implementation
Copyright
Preface
References. Cited
Contributors
Acknowledgments
Part One PGC fundamentals
Why study this?
1 An introduction
Chromatographic separation
The gas chromatograph. The basic instrument
The process instrument
The oven. Temperature control
Temperature programming
The sample injection valve. Laboratory and online practice
Plug injection
Gas sample injection
Liquid sample injection
The column. The separating device
It takes time
Multiple columns
SCI-FILE: On Column Types. Introduction to SCI‐FILEs
Two kinds of column
Packed columns
The detector. Making the measurements
The chromatogram
Knowledge Gained
Did you get it? Self‐assessment quiz: SAQ 01
Student evaluation test: SET 01
References. Cited
Figures
New technical terms
Note
2 Peak shape
How columns work
What happens inside the column
How gas and liquid interact
Troubleshooting tips
How peaks form. Forming an equilibrium
The effect of movement
A peak appears
Effect of more equilibria
Some conclusions
Identical molecules – different behavior
All peaks are symmetrical
More equilibria – narrower peaks
More equilibria – taller peaks
Retention at the apex
More equilibria – same retention time
SCI-FILE: On Solubility. Solubility
Partition
Distribution
Limitations
Knowledge Gained
Did you get it? Self‐assessment quiz: SAQ 02
Student evaluation test: SET 02
References
Figures
Equation
Symbols
New technical terms
3 Separation
How peaks get separated
A more realistic explanation
A challenge question
Significance of the air peak
The answer
Measurements from chromatograms. A practical task
Typical calculations
Knowledge Gained
Did you get it? Self‐assessment quiz: SAQ 03
Student evaluation test: SET 03
References
Figures
Equations
Symbols
New technical terms
4 Peak patterns
Migration rate
Predictable patterns in peak position. Space or time
Spatial or temporal separation
Predictable patterns in peak width. Distance or duration
SCI-FILE: On Chemical Names. Hydrocarbons. Paraffins
Olefins
Acetylenes and more
Shorthand notation
Predictable patterns in retention. The doubling rule
Challenge question
A process of elimination
Temperature programming
Relative retention
Separation and resolution
Resolution
Predictable patterns in resolution
Knowledge Gained
Did you get it? Self‐assessment quiz: SAQ 04
Student evaluation test: SET 04
References
Figures
Equations
Symbols
New technical terms
Part Two PGC analytics
Why study this?
5 Industrial gas chromatographs
Process analyzers. Introduction to process analysis
The measurement of quality
Process gas chromatographs. Versatile and reliable
PGC development
The value of analysis
Competing technologies. Gas chromatograph or spectrophotometer?
Speed of response
The outlook
The PGC analytics unit. Introduction
Carrier gas supply system
Sample injection system
Chromatographic valves
Column system
Detectors
Temperature‐controlled ovens
Knowledge Gained
Did you get it? Self‐assessment quiz: SAQ 05
Student evaluation test: SET 05
References. Cited
Figures
Table
Symbol
New technical terms
Note
6 Carrier gas system. Choice of carrier gas. Carrier gas purpose
Choice of carrier gas
Hydrogen carrier gas
Helium carrier gas
Nitrogen carrier gas
Argon carrier gas
Mixed carrier gases
Carrier gas purity
Analytical effect of impurities
Damaging effect of impurities
Maintenance of gas cleaners
Carrier gas supply system
Carrier gas supply line
Pressure regulation
Mechanical pressure regulators
Electronic pressure controllers
Flow regulation
Measuring the carrier gas flow rates
Setting the flow rates
Optimum flow rate
Knowledge Gained
Did you get it? Self‐assessment quiz: SAQ 06
Student evaluation test: SET 06
References. Cited
Table
Figures
Symbols
New technical terms
7 Sample injection
Introduction
Injecting gas samples. Gas sample volume
Gas sample temperature
Gas sample pressure
Injecting liquid samples. Less preferred
Vaporizing a liquid sample
Liquid sample volume
Liquid sample temperature
Liquid sample pressure
Other techniques. Sample splitting
Remote sample injection
Normalization
SCI-FILE: On Analytic Units. A fable
Constant sample size
Different ratio units
Injected quantity
Conversion of units
Knowledge Gained. Practice
Theory
Did you get it? Self‐assessment quiz: SAQ 07
Student evaluation test: SET 07
References. Cited
Tables
Figures
Symbols
New technical terms
Note
8 Chromatographic valves
Valve technology. Evolution
The strange effect of competition
Valve types. Solenoid instrument valves
Spool or piston valves
Slide valves
Rotary valves
Diaphragm valves
Plunger valves for liquid injection
Other switching techniques
Valve leaks. About leaks
Valve leak mitigation
Knowledge Gained
Did you get it? Self‐assessment quiz: SAQ 08
Student evaluation test: SET 08
References. Cited
Table
Figures
New technical terms
9 Column systems
Two fundamental issues. The general elution problem
The housekeeping rule
The temperature ramp solution
The multiple column solution
The choice
Delayed injection
Four types of column system. Recognizing the functions performed
Type A: A single column
Type B: Multiple columns, single detector
Type C: Multiple detectors, single injector
Type D: Multiple sample injectors
Elemental column systems. Useful techniques
Backflush column system
Distribution column system
Heartcut column system
Trap‐and‐hold column system
The real power
Endnote
Knowledge Gained
Did you get it? Self‐assessment quiz: SAQ 09
Student evaluation test: SET 09
References. Cited
Table
Figures
New technical terms
10 Detectors
Introduction
Types of detector. Two measured variables
Concentration detectors
Rate‐of‐arrival detectors
Multiple detectors
Signal capture
SCI-FILE: On Detectors
Signal noise
Speed of response
Sensitivity
Concentration detectors
Rate‐of‐arrival detectors
Thermal conductivity detector. TCD application
TCD basic function
TCD detection principle
TCD thermal elements
TCD electrical arrangement
TCD electrical improvements
TCD performance enhancement
Flame ionization detector. FID application
FID detection principle
FID makeup gases
FID sensitivity
FID vent arrangements
FID methanator
Flame photometric detector. FPD application
FPD detection principle
FPD concerns
Other detectors
Electron capture detector
Helium ionization detector
Photoionization detector
Pulsed discharge detector
Knowledge Gained. Concentration detectors
Rate‐of‐arrival detectors
Theory
Thermal conductivity detector
Flame ionization detector
Flame photometric detector
Other ionization detectors
Did you get it? Self‐assessment quiz: SAQ 10
Student evaluation test: SET 10
References. Cited
Tables
Figures
Equations
Symbols
New technical terms
11 Temperature control
Need for stability
Sample volume
Retention times
Detector baseline
Heating technique
The air‐bath oven. Heating with air purging
The airless oven. Heating without air
The 2008 ABB PGC1000
The 2014 Rosemount Danalyzer 370XA PGC
The 2009 Rosemount 700XA PGC
The 2002 Maxum Edition II
Direct column heating. Resistive heating
The ABB approach
The Teledyne Falcon approach
A few cautions
Summary of heating methods
PGC standardization. Realities of the market
The applications engineering conundrum
MEMS technology
The 2002 siemens MicroSAM
A closing thought
Knowledge Gained
Did you get it? Self‐assessment quiz: SAQ 11
Student evaluation test: SET 11
References. Cited
Table
Figures
New technical terms
Part Three PGC control
Why study this?
12 Event scheduling
A sequence of actions. Program timing
Autozero
Atmospheric referencing
Sample injection
Step stream
Column switching
Peak gating
Initiate a calculation
Data transmission
Alarm notifications
End‐of‐cycle
Event markers
Calendar events
Timing mechanisms. Mechanical programmers
Electronic timers
Microprocessor control
The program or method
Control of analyzer operation
Temperature control
Pressure control
Peak identification
Fixed‐time gating
Retention time tracking
Knowledge Gained
Did you get it? Self‐assessment quiz: SAQ 12
Student evaluation test: SET 12
References. Cited
Figures
New technical terms
13 Data display techniques
The chromatogram display. Detector signal
Digitized chromatograms
Chromatogram autozero
Peak height calibration
Peak area calibration
The bargraph display. The paper saver
The trend record. Analog peak processing
Digital signal processing
The minicomputer story
The ubiquitous microprocessor
A regression perhaps?
Central maintenance station
Continuous analyzer controllers
PGC function alarms. Indicators
Alarm notifications
Knowledge Gained
Did you get it? Self‐assessment quiz: SAQ13
Student evaluation questions: SET‐13
References. Cited
Table
Figures
New technical terms
14 Peak area integration
Digital chromatogram processing. Pulse frequency digitization
Sampled‐data digitization
Signal noise measurement
Signal noise reduction
Quantifying the analyte peaks
Forced integration
Slope detection
Errors from baseline disturbances
Troubleshooting aids
Measuring overlapping peaks. Avoiding the problem
Tackling the problem
Perpendicular drop method
Don't integrate to a valley point
Angular drop or allocated area
Tangent skim method
Effect of setup mistakes
Knowledge Gained
Did you get it? Self‐assessment quiz: SAQ 14
Student evaluation test: SET 14
References. Cited
Figures
New technical terms
15 Calibration
Measurement principles. Terminology
Random error
Systematic error
Uncertainty
Accurate calibration
Calibration and validation
Calibration methods. External standard method
Normalization
Calibrating a composite peak
Grab sample calibration
Internal standard method
Area percentage method
SCI-FILE: On Response Factors. External standard
Normalization
Internal standard
Area percentage
Knowledge Gained
Did you get it? Self‐assessment quiz: SAQ 15
Student evaluation test: SET 15
References. Cited
Figure
Equations
Symbols
New technical terms
Answers to self‐assessment questions. SAQ‐01
SAQ‐02
SAQ‐03
SAQ‐04
SAQ‐05
SAQ‐06
SAQ 07
SAQ 08
SAQ 09
SAQ 10
SAQ 11
SAQ 12
SAQ 13
SAQ 14
SAQ 15
Bibliography. Suggestions for further reading
Glossary
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Z
Index
WILEY END USER LICENSE AGREEMENT
