ABSTRACT
Introduction 1144 The Selection Process 1144
Problem Definition 1144 Information Gathering 1145 Technique or Analyzer Selection 1147
Specificity (Selectivity) 1148 Accuracy and Precision 1148 Calibration 1148 Analysis Frequency 1149 Kinds of Analyzers 1149 Separation Techniques 1149 Other Separation Techniques 1150 Spectroscopic or Radiant Energy
Techniques 1150 Ultraviolet and Visible 1150 Fluorescence 1151 Infrared and Near-Infrared 1151 Raman 1152 Microwave and Radio Frequency 1152 Refractometry 1153 Turbidity and Particle Size 1153 Nuclear Techniques 1153
Electrochemical Sensors 1154 Potentiometric 1154 Conductive 1156 Amperometric 1156 Chemical Techniques 1156 Miscellaneous Techniques 1156
Quartz Crystal Microbalances 1156 Mass Spectrometry 1157
Nuclear Magnetic Resonance 1157 Analyte-Specific Techniques 1157
Water 1157 Oxygen 1157
Sampling 1157 Probe Cleaners 1159
Analyzer Location 1161 Handling the Data 1162 Maintenance 1162 Cost 1162 Summary 1163 References 1168 Bibliography 1168
8.2 Analyzer Sampling: Process Samples 1170
Introduction 1171 General Considerations 1171
Feasibility Evaluation 1171 Sample Data Requirements 1171 Sample Takeoff Point 1172 Sample Transport 1173 Transport Lag 1173 Sample Disposal 1174 Ambient Considerations 1174 Test and Calibration 1174
Components of Sampling Systems 1175 Selecting the System Components 1175 Filter Designs 1175
Separating Liquids from Gases 1175 Spargers, Packed Towers, and Strippers 1176 Separating Two Liquid Phases 1177
Removing Gas Bubbles from Liquids 1178 Slipstream and Bypass Filters 1178 Self-Cleaning and Rotary Disc Filters 1179
Keeping Probes Clean 1179 Homogenizers 1180 Sample Conditioning 1180
Vaporizing Samples 1182 Entrainment Removal 1182 Selection of Component Materials 1182
Applications 1183 Gas Sampling Probes 1183 Stack Gas Sampling 1183
Automatic Stack Sampling 1183 Automatic Liquid Samplers 1184
Sampling of High-Pressure Condensate 1184
Chemical Reactor Samplers 1184 Duckbill Samplers 1185
Solids Sampling 1185 Sampling Difficult Processes 1186
Trace Analysis Sampling 1186 Multistream Switching 1187
References 1188 Bibliography 1188
8.3 Analyzer Sampling: Stack Particulates 1189
Introduction 1189 The EPA Particulate Sampling System 1189
Microprocessor-Controlled Stack Sampling 1189
The Pitot Tube Assembly 1190 Type S Pitot and the Sampling Probe 1190 Selecting the Sampling Point 1192 Traversing Point Locations 1192 Pitot Tube Calculation Form 1192 Sampling Velocity for Particle
Collection 1192 Isokinetic Sampling 1192
Heated Compartment (Hot Box) 1193 Ice-Bath Compartment (Cold Box) 1193 Control Unit 1195
Automatic Sampling Trains 1195 Sampling for Gases and Vapors 1196 References 1196 Bibliography 1197
8.4 Analyzers Operating on Electrochemical Principles 1198
Introduction 1199 Voltametric Analysis 1199
Current, Voltage, and Time 1200 Potentiometry 1201
Galvanic and Electrolytic Probes 1201 Membrane-Covered Probes 1202
Amperometry 1202 Solid Electrodes 1203
Polarography 1204 Advantages 1205
Coulometry 1205 Controlled Potential Coulometry 1205
Conclusions 1205 Limitations 1206 Advances 1206
Reference 1206 Bibliography 1206
8.5 Air Quality Monitoring 1207
Introduction 1207 Air Quality Monitoring Systems 1207
Purpose of Monitoring 1208 Impact of Single Sources 1208
Research Needs 1209 Monitoring in Urban Areas 1209 Sampling Site Selection 1210 Static Methods of Air Monitoring 1210
Dust-Fall Jars 1211 Lead Peroxide Candles 1211 Other Static Methods 1211
Laboratory Analyses 1211 Automatic Monitoring 1212
Sensors 1212 Data Transmission 1212 Data Processing 1213
Averaging Times 1213 Displays 1213
Audits 1213 Automatic Analyzers 1213
Infrared Spectrometers 1213 Handheld Indoor Air Quality
Monitors 1214 Sampling of Ambient Air 1214
General Air Sampling Problems 1214 Sampling for Gases and Vapors 1216
Absorption 1217 Liquid Absorption 1217 Impingers 1217 Fritted Absorber 1217 Adsorption 1218 Freeze-Out Sampling 1218
Sampling of Particulates 1218 Air Filters 1219 Fiberglass Filters 1219 Impingement and Impaction 1219 Impactors 1219 Electrostatic Precipitation 1220 Thermal Precipitators 1220
Reference 1221 Bibliography 1221
8.6 Biometers 1222
Introduction 1222 ATP Analysis 1222 Luminescence Biometer 1223 Reference 1223 Bibliography 1223
8.7 Biological Oxygen Demand, Chemical Oxygen Demand, and Total Oxygen Demand 1224
Introduction 1224 Oxygen Demand 1225
The Seed 1225 pH 1225 Temperature 1225 Toxicity 1225 Incubation Time 1226 Nitrification 1226
Biological Oxygen Demand 1226 Five-Day BOD Procedure 1226
DO Determination and Standards 1226 Instrumentation 1226
Extended BOD Test 1227 Manometric BOD Test 1227
Automatic Recording 1228 BOD Assessment in Minutes 1228 Electrolysis System for BOD 1229
Chemical Oxygen Demand 1229 Standard Dichromate COD Procedure 1229 COD Detector 1229 Automatic On-Line Designs 1229
Total Oxygen Demand 1231 Sample Valves 1231 Oxygen Detector 1232 Calibration 1232 Interferences 1232 Applications 1233
Correlation between Measurement Techniques 1233 Variations in Oxygen Demand 1233 BOD and COD Correlation 1233
BOD and Other Methods 1233 References 1234 Bibliography 1234
8.8 Calorimeters 1235
Introduction 1235 Terminology 1236
British Thermal Unit 1236 BTU Dry 1236 BTU Saturated 1236 Combustion Air Requirement Index 1236 Gross Calorific Value 1236 Net Calorific Value 1236 Wobbe Index 1236
Units, Accuracy, and Output Signals 1236 Design Variations 1238
Water-Temperature-Rise Calorimeter 1238 Air-Temperature-Rise Calorimeter 1238 Airflow Calorimeter 1238 Residual Oxygen Calorimeter 1239 Chromatographic Calorimeter 1240 Expansion Tube Calorimeter 1240 Adiabatic Flame Temperature 1240 Thermopile Calorimeter 1240
Applications 1240 Sample Conditioning 1241 Conclusion 1241 Reference 1241 Bibliography 1241
8.9 Carbon Dioxide 1242
Introduction 1243 Ambient Air Measurement 1243
Nondispersive Infrared Type 1243 Gas Filter Correlation Type 1244
Source Measurement 1244 Bibliography 1244
8.10 Carbon Monoxide 1245
Introduction 1246 Calibration Techniques 1246 Nondispersive Infrared Analyzers 1247
Interferences 1247 Gas Filter Correlation 1247
Mercury Vapor Analyzer 1248 Gas Chromatograph 1248 Electrochemical Analyzer 1248
Portable Monitors 1249 Catalytic Analysis 1249 Spot Sampling of Ambient Air 1249 Conclusions 1250 References 1250 Bibliography 1250
8.11 Chlorine 1251
Introduction 1252 Residual Chlorine Analyzers 1252
Colorimetric Analyzers 1253 Automatic Colorimetric Analyzer
Features 1253 Amperometric Analyzers 1254
Types of Amperometric Analyzers 1254 Free Residual Chlorine Analysis 1254 Membrane Probes 1255 Buffers and Reagents 1256 Electrode Cleaners 1256
Conclusions 1256 Bibliography 1257
8.12 Chromatographs: Gas 1258
Introduction 1259 Basic Chromatographic Instrumentation 1260 Components of a Process Gas
Chromatograph 1261 Analyzer 1262 Oven 1262 Valves 1263
Rotary Valve 1263 Sliding Plate 1264 Diaphragm 1265
Columns 1265 Packed Columns 1265 WCOT (Capillary) Columns 1266
Column and Valve Configurations 1266 Hardware 1267
Sample Injection 1267 Backflush 1268 Heart-cutting 1269
Detectors 1269 Thermal Conductivity Detector 1270 Flame Ionization Detector 1271 Flame Photometric Detector 1272 Pulsed Flame Photometric Detector 1273 Orifice-Capillary Detector 1274 Miscellaneous Detectors 1275
Photoionization Detector 1275 Electron Capture Detector 1275 Discharge Ionization Detectors 1276
Carrier Gas Flow Control 1277 Programmer-Controller 1277
Programmer 1278 Peak Processor 1278 Data Acquisition 1278
Input-Output 1278 Communication 1278 Operator Interface 1280 Alarms and Diagnostics 1281 Quantitation 1281
Sample Handling 1281 Sample Probe 1282 Sample Transport 1282
Sample Conditioning 1283 Multistream Analysis 1283 Sample Disposal 1285
Installation 1286 Summary 1287 Acknowledgment 1287 References 1287 Bibliography 1288
8.13 Chromatographs: Liquid 1289
Introduction 1289 Comparison with Gas Chromatographs 1290
Carrier Flow 1290 The Main Components 1290
HPLC Column Selectivity and Resolution 1290 Carrier Supply 1291
Supply Pumps 1291 Pressure and Flow Controls 1291 Valves 1291
Columns 1292 Liquid-Partition Columns 1292 Liquid-Adsorption Columns 1292 Gel-Permeation Columns 1292 Ion Exchange Columns 1293 Electrophoresis 1293
Detectors 1293 Optical Absorbance 1293 Refractive Index 1293 Dielectric Constant 1293
Applications 1293 Reference 1293 Bibliography 1293
8.14 Coal Analyzers 1295
Introduction 1295 Thermogravimetry 1295
Bituminous Coal Analysis 1295 Gross Calorific Value 1296 Total Sulfur Analysis 1296 Ash Analysis 1297 On-Line Monitors 1297
Gamma-Based Analyzers 1298 Recent Developments 1298
References 1298 Bibliography 1298
8.15 Colorimeters 1299
Introduction 1300 Color Measurement 1300
Absorbance and Transmittance Colorimetry 1300
Spectrophotometric Analyzers 1300 Spectrophotometer Design 1301
Tristimulus Method (Reflectance) 1301 The Lab Algorithm of the Textile Industry 1302
Continuous Color Monitors 1303 In-Line Liquid Color Measurement 1303 On-Line Shade Monitors 1303
References 1303 Bibliography 1303
8.16 Combustibles 1304
Introduction 1305 Selection Considerations 1305
Terminology, Definitions, and Background Information 1305
Catalytic Combustion on a Heated Filament 1306 Limitations 1306 Measuring Circuits 1307
Thermocouple Detector 1307 Wheatstone Bridge Detector 1307
Diffusion Head Analyzers 1308 Sampling System 1308 Accessories 1309
Selection of Complete Installation 1309 Remote Head System 1309 Multiple Head System 1309 Tube Sampling System 1310
Conclusions for Catalytic Detectors 1310 Flame Ionization and Photoionization
Detectors 1311 Flame Ionization Detectors 1311 Photoionization Detectors 1311
Infrared Combustibles Detectors 1311 Point Infrared Systems 1312 Area (Open-Path) Infrared Systems 1313 Hydrocarbon Gases in the Atmosphere 1314 Point Measurement 1315
Bibliography 1315
8.17 Conductivity Analyzers 1316
Introduction 1316 Theory of Operation 1317 The Cell Constant 1317
Cell Dimensions 1318 Two-Electrode Cells 1319 Four-Electrode Measurement 1319 Electrodeless Cells 1319
Measurement Applications 1320 Concentration Measurements 1320 High-Purity Water Measurements 1320 Corrosive and Fouling Applications 1320
Calibration and Maintenance 1321
Calibration of Conductivity Sensors 1321 Maintenance of Conductivity Cells 1322
Conclusion 1322 References 1322 Bibliography 1322
8.18 Consistency Analyzers 1323
Introduction 1323 In-Line Consistency Measurement 1324
Mechanical Devices 1324 Probe Type 1324 Blade Types 1325 Rotating Sensors 1325
Optical Sensors 1326 Measuring Woodfree Pulp 1326 Consistency of Pulp Containing Wood 1326
Summary 1328 References 1328 Bibliography 1328
8.19 Corrosion Monitoring 1329
Introduction 1329 Corrosion Monitoring Techniques 1329 Corrosion Coupon Monitoring 1330
Time of Exposure 1331 Advantages and Limitations 1332
Electrical Resistance Monitors 1332 Advantages and Limitations 1332
Linear Polarization Resistance Monitors 1333 Advantages and Limitations 1334
Bibliography 1334
8.20 Differential Vapor Pressure Sensor 1335
Introduction 1335 Design and Operation 1335 Limitations 1337 Reference 1338 Bibliography 1338
8.21 Dioxin Analysis 1339
Introduction 1339 Principle of Operation 1339
Sample Recovery 1339 Sample Extraction 1340 Analysis 1340
Conclusions 1341 Bibliography 1341
8.22 Elemental Monitors 1342
Introduction 1342 Atomic Absorption Spectrometer 1342 Inductively Coupled Plasma Detector 1343
Operating Principle 1344 Selecting among AA and ICP 1344 X-Ray Fluorescence Spectrometer 1344
Instrumentation 1345 Bibliography 1346
8.23 Fiber-Optic Probes 1347
Introduction 1347 Principle of Measurement 1347 Instrumentation 1347
Glass Optical Fiber 1348 Plastic Optical Fiber 1348 Probes 1348
Wand Probe 1348 Spectra-Caliper Probe 1348 Transmission Probe 1348 Long-Path-Flow Tube 1349 GEM Probe 1349 Six-to-One Probe 1349
Sample Interfaces 1350 Detectors 1350 Software 1350
Applications 1350 Absorption 1350 Fluorescence 1350
Optrodes 1351 Oxygen Probe 1351
Scattering 1351 Refractive Index 1352
Bibliography 1352
8.24 Fluoride Analyzers 1353
Introduction 1354 Types of Fluoride Compounds 1354 Analyzer Types 1355
Gas and Vapor Analyzers 1355 Detector Tubes 1355 Electrochemical Cells 1355 Paper Tape 1356 Ion Mobility Spectrometry 1356 Infrared Spectroscopy 1356 Ion-Specific Electrodes 1356 Silicon Dioxide Sensors 1356 Laboratory Methods 1356
Organic Fluoride Analysis 1357 Other Methods 1357
References 1357 Bibliography 1357
8.25 Hydrocarbon Analyzers 1358
Introduction 1359 Analyzer Types 1359
Flame Ionization Detectors 1359 Gas Chromatography 1360
Calibration 1361 Nonmethane Hydrocarbons 1361 Reactive Hydrocarbons 1361
Spectrometric Methods 1361 Laser-Induced Doppler Absorption
Radar 1361 Spectroscopy Perimeter Monitoring 1362
Ion Mobility Spectroscopy 1362 Hydrocarbon Dew-Point Meter 1362
Calibration Methods 1362 Assessment 1362 Bibliography 1363
8.26 Hydrogen Sulfide 1364
Introduction 1365 Electrochemical Cells 1365 Gold-Film and Semiconductor Sensors 1365
Solid-State Sensors 1366 Lead Acetate Tape Staining 1366 Photometric Analysis 1367
Direct Photometric Analyzer 1367 Gas Chromatography with Flame Photometric
Detector 1367 Tail Gas Analyzer 1367
Reference 1368 Bibliography 1368
8.27 Infrared and Near-Infrared Analyzers 1369
Introduction 1371 Principles of IR and NIR Analysis 1371
Beer-Lambert Law 1373 Definitions of Terms and Configurations 1374 IR Instrument Designs 1375
Single-Beam Configuration 1375 Dual-Beam Configuration 1375
Dual-Beam Design for Stacks 1376 Infrared Analyzers for the Laboratory 1377
Grating Spectrophotometers 1377 Filter Spectrometers 1377 Fourier Transform Spectrometers 1377 Tunable Lasers 1378
Laboratory Instruments in Process Measurement 1378
Infrared Analyzers for Process Applications 1378 Single-Component Analyzers 1378
Design Variations 1378 Gas Filter Correlation Spectrometers 1379 Filter Analyzers 1379 Multiple-Component Fixed Filter
Analyzer 1380 Programmed Circular Variable Filter
Analyzer 1380 Infrared Sources 1380 Infrared Detectors 1380
NDIR Detectors 1381 Thermal Detectors 1381 Photoconductive Detectors 1381
Selecting the Cell 1381 Path Length Selection 1381 Gas Cells 1381 Liquid Cells: Transmission Type 1382 Liquid Cells: Reflection Type 1382
Solid Samples 1382 Calibration: Sources of Analyzer Drift 1382
Linearity 1383 Packaging 1383
Applications and Advances 1383 Near-Infrared Analyzers 1384
Interpreting the Absorption Bands 1385 Sample Temperature Control 1385 Fiber Optics 1385 Types of NIRs 1385 Sources 1386 Gases 1386 Liquids 1386 Solids 1386 Calibration Transfer 1386 References 1386
Bibliography for Infrared Analyzers 1386 Bibliography for Near-Infrared Analyzers 1387
8.28 Ion-Selective Electrodes 1388
Introduction 1388 The Nernst Equation 1389
The Reference Electrode 1390 Concentration and Activity 1391 Ionic Strength Adjustment Buffers 1391 Temperature Effects 1392
The Isopotential Point 1392 Role of Electrode Internals and
Calibration 1392 System Accuracy 1393
Laboratory Devices 1393
Process Applications 1393 Types of Electrodes 1393
Glass 1393 Solid State 1394 Liquid-Ion Exchange 1395
Measurement Range 1395 Interferences 1396
Solution Interference 1396 Calibration Solutions 1396 Advantages and Disadvantages 1397
Precision and Accuracy 1398 Conclusions 1398 References 1398 Bibliography 1398
8.29 Mass Spectrometers 1399
Introduction 1399 Principle of Operation 1400
Sample Input 1400 Sample Ionization 1400 Ion Separation 1400
Magnetic Sectors 1401 Quadrupole Filter 1402 Ion-Trapping Section 1403 Time-of-Flight Filter 1403
Ion Detection 1403 Vacuum Environment 1404 Data Reduction and Presentation 1404
Residual Gas Analyzers 1405 Conclusions 1405 Bibliography 1405
8.30 Mercury in Ambient Air 1407
Introduction 1408 Sample Collection and Concentration 1408 Impinger Collection Methods 1408
Particulate Sampling 1408 Vapor Sampling 1409
Amalgamation on Wettable Metals 1409 Sampling Tubes 1409
Activated Absorption 1410 Conversion of Mercury Vapors 1410 Methods of Detection 1410 Ultraviolet Light Absorption 1410
Atomic Absorption Spectrophotometry 1410 Flameless Atomic Absorption
Spectroscopy 1410 Colorimetric Methods 1411
Dithizone 1411 Selenium Sulfide and Others 1411
Gas Chromatography for Mercury Organics 1411
Atomic Fluorescence Spectroscopy 1411 Other Analytical Procedures 1412
References 1412 Bibliography 1412
8.31 Mercury in Water 1413
Introduction 1414 Total Mercury Detection 1414
Sample Treatment 1414 Colorimetric Detection 1414
Interference by Copper 1415 Analysis Procedure 1415
Atomic Absorption Spectrophotometry 1415 Analysis Procedure 1416
On-Line Measurement 1416 Organic Mercury Detection 1416
Sample Treatment 1416 Gas Chromatography 1417 Thin-Layer Chromatography 1418
Bibliography 1419
8.32 Moisture in Air: Humidity and Dew Point 1420
Introduction 1421 Definitions 1422 Relative Humidity Sensors 1422
Wet and Dry Bulb Hygrometers 1422 Wet-Dry Bulb Hygrometers 1422 Assman Psychrometers 1424
Calculation of Relative Humidity 1424 Hair Hygrometers 1424 Cellulose Hygrometers 1425 Solution Resistance Elements
(Dunmore Cells) 1425 Polystyrene Surface Resistivity
(Pope Cells) 1425 Thin-Film Capacitance 1425
Metal Oxide Sensor 1426 Polymer Sensor 1427 Autocalibration 1427
Dew-Point Hygrometers 1428 Solution-Conductivity Type 1428
Installation 1428 Sampling System 1428 Limitations 1429
Condensation on a Chilled Surface 1429 Surface Conductivity Type 1429
Sampling System 1429 Limitations 1430
Chilled-Mirror Type 1430
Cooling Methods 1430 Automatic Standardization 1431 Limitations 1431
Cycled Chilled-Mirror Probe 1432 Moisture Indicators 1432
Microprocessor-Based Indicators 1432 Conclusion 1433 References 1433 Bibliography 1433
8.33 Moisture in Gases and Liquids 1434
Introduction 1435 Laboratory Analyzers 1435 Process Analyzers 1435
Sampling Systems 1435 Electrolytic Hygrometer 1436
Avogadro’s Law 1436 Recombination Effect 1437 Cell Limitations 1437 Liquid Samples 1438 Sampling System 1438
Capacitance Hygrometer 1438 Sampling Systems 1439 Thin-Film Capacitance Probes 1439 Limitations 1439
Impedance Hygrometer 1440 Installation 1441 Sampling System 1441 Limitations 1441
Piezoelectric Hygrometer 1441 Sampling System 1442 Limitations 1442
Heat-of-Adsorption Hygrometer 1442 Sampling System 1443 Limitations 1443
Infrared Absorption Hygrometer 1443 Sampling System 1443 Limitation 1444
Microwave Absorption Hygrometer 1444 Limitations 1444
Dipole Polarization Effect Moisture Sensor 1444
Sampling System 1445 Limitations 1445
Cavity Ring-Down Spectroscopy (CRDS) Moisture Analysis 1445
Sampling System 1445 Limitations 1445
Neutron Backscatter Moisture On-Line Analyzer 1445
Sampling System 1446 Limitations 1446
Calibration of Moisture Analyzers 1446
Limitations 1448 Bibliography 1448
8.34 Moisture in Solids 1450
Introduction 1451 Laboratory Analyzers 1451
Karl Fischer Titration 1451 Industrial Detectors 1451
Nuclear Moisture Gauge 1451 Theory of Operation 1451 The Measuring System 1452 Limitations 1452
Infrared Absorption or Reflection 1452 Measurement and Installation 1452 Limitations 1453
Microwave Attenuation 1453 Basis Weight Compensation 1453 Moisture in Coal 1453 Sugar Industry Applications 1454
Capacitance Moisture Gauge 1454 Sensor Designs 1454 Capacitance Measurement 1455 Limitations 1455
Resistance Moisture Gauge 1455 Limitations 1455
Impedance Moisture Gauge 1456 Nuclear Magnetic Resonance 1456 Radio Frequency Absorption 1456
Conclusions 1456 Bibliography 1456
8.35 Molecular Weight 1457
Introduction 1458 The Average Molecular Weight 1458 Osmometers 1459
The Membrane Osmometer 1459 Automatic Osmometers 1459
Vapor Pressure Osmometers 1460 Light-Scattering Photometer 1461
The Zimm Plot 1461 The Photometer 1462
Viscometers 1462 Viscosity vs. Molecular Weight 1463 Intrinsic Viscosity 1463
Gel-Permeation Chromatography 1463 Differential Refractometer Sensor 1463 The Complete Instrument 1464 Molecular Weight from Chromatograph
Output 1464 End Group Determination 1466 Electron Microscope 1466
Transmission Electron Microscope 1466
Advantages and Limitations 1466 Ultracentrifuge 1467
Sedimentation Velocity 1467 Sedimentation Equilibrium 1467 Instrument Construction 1467
Conclusions 1467 Bibliography 1467
8.36 Nitrate, Ammonia, and Total Nitrogen 1469
Introduction 1469 Environmental Significance 1469
Nitrification and Denitrification 1470 Ammonia Nitrogen 1470
Ammonium and Total Nitrogen Probes 1470 Chemiluminescence 1471
Nitrite Measurement 1471 Nitrate Measurement 1471 Total Nitrogen 1472
Kjeldahl Method 1472 Chemiluminescence Analyzer 1472
References 1473 Bibliography 1473
8.37 Nitrogen Oxide Analyzers 1474
Introduction 1475 Industrial Emission Monitoring 1475
Paramagnetic Analyzers 1475 Thermal Conductivity Analyzers 1475 Nondispersive Infrared Analyzers 1475 Ultraviolet Analyzers 1475 Chemiluminescent Analyzers 1475 Electrochemical Sensors 1475 Gas Chromatography 1477
Ambient Air Monitoring 1477 Calibration Methods 1477
Dynamic Calibration 1477 Static Calibration 1477
NO-NO
Combination Analysis 1477 Series Analysis 1478
Colorimetric Determination 1478 The Griess-Saltzman Method 1478 The Jacobs-Hochheiser Method 1478
Portable Monitors 1479 Conclusions 1479 References 1479 Bibliography 1479
8.38 Odor Detection 1480
Introduction 1481 The Measurement of Odor 1481
Sensitivity 1481 Flexibility 1481 The Gas Chromatograph 1481
The Human Olfactory System 1482 Sample Preparation 1482
Odor Panels 1482 Training of an Odor Panel 1483
Tests 1483 The Electronic Nose 1483
Polymeric Film Sensors 1483 Metal Oxide Sensors 1484 Other Sensors 1484 Training 1484 Applications 1484
References 1484 Bibliography 1484
8.39 Oil in or on Water 1486
Introduction 1486 Process Industry Measurements 1486
Capacitance-Type Water-in-Oil Detectors 1487
Radio-Frequency (Microwave) Sensors 1487
Rag Layer and Tank Profiler Sensors 1487
Water-in-Oil Probes 1487 Conductivity and Capacitance Sensors 1488 Ultrasonic Sensors 1488 Nuclear Sensors 1489 Ultraviolet Oil-in-Water Analyzer 1489
Environmental Pollution Sensors 1490 On-Off Oil-on-Water Detector 1491
Continuous Oil-on-Water Detector 1491 Oil-Thickness-on-Water Detector 1491 Oil-in-Water Detector 1491
Conclusions 1492 Reference 1492 Bibliography 1492
8.40 Open Path Spectrophotometry (UV, IR, FT-IR) 1493
Introduction 1493 Applications 1494 Toxic Sensor Types 1494
Instrument Designs 1494 Blackbody Radiation Interference 1495 Interferometry 1496 Beer’s Law and Path Integrated
Concentrations 1496 Path Integrated Concentration 1496
Open Path FTIR Spectrometry 1496
Interferometer 1497 Transfer Optics and the Detector 1497 Data System/Controller 1497 Configurations 1497
Open Path Ultraviolet Spectrometry 1498 The OP-UV Spectrometer 1498
Open Path Tunable Diode Laser Spectrometry 1499 Diode Lasers 1501 Applications 1502 Principle of Operation 1502
Wavelength Modulation Spectrometry 1502 Open Path Detection of Combustibles 1503
OP-HC Detector Design 1504 Sources and Interference 1504 Transmitter-Receiver Separation 1504 Advantages and Limitations 1505
References 1505 Bibliography 1505
8.41 Oxidation-Reduction Potential (ORP) 1506
Introduction 1507 ORP Measurement Principles 1508
The ORP Reaction 1508 Half-Cell Reactions 1508
Half-Reaction 1509 Half-Reaction 1509 Overall Reaction 1509
The Cell Potential 1509 Cell Potential at Equivalence Point 1509 Chromium Example 1509 Microprocessor-Based Units 1510
ORP Sensors 1510 The Nernst Equation 1511 Electrode Mounting 1511
ORP Applications 1512 Chromium Reduction 1512
ORP Maintenance 1512 ORP Control 1512
Residence Time 1513 References 1513 Bibliography 1513
8.42 Oxygen in Gases 1514
Introduction 1515 Paramagnetic Oxygen Detectors 1515
Deflection Analyzer 1516 Thermal Analyzer 1516 Dual-Gas Analyzer 1517
Catalytic Combustion Oxygen Detectors 1517 Electrochemical Oxygen Detectors 1518
High-Temperature Zirconium Oxide Fuel Cells 1518
Cell Design and Limitations 1519 Self-Diagnostics and Self-Cleaning 1520
High-Temperature Current-Mode Oxygen Detectors 1520
Galvanic Detectors 1520 Capillary Systems 1521 Detector Design 1521 Advantages and Limitations 1521
Coulometric Sensor 1522 Polarographic Sensor 1522
Spectroscopic Oxygen Detection 1522 Mass Spectroscopy 1522 Near Infrared Spectroscopy 1522
TDLAS Designs 1523 Other Oxygen Detection Methods 1524 Reference 1524 Bibliography 1524
8.43 Oxygen in Liquids (Dissolved Oxygen) 1526
Introduction 1527 Probe Cleaners and Newer Sensors 1527
Polarographic Cell 1528 Sample Temperature and Flow 1528
Galvanic Cell 1528 Cell Designs 1529 Special and Flow-Through Cells 1529 Probe Design 1529
Installation 1530 Flow-Through Design 1530
Coulometric Sensor 1531 Multiple-Anode Detector 1531 Thallium Cells 1531
Thallium Differential Conductivity Analyzer 1531
Fluorescence-Based Sensors 1532 Sensor Design and Operation 1532
Other Detection Methods 1532 Operational Considerations for All
Sensors 1532 Calibration Methods 1533 Temperature Compensation 1533 Pressure Effects 1534 Salinity Effects 1534 Application Considerations 1534
Mounting Considerations 1535 Bibliography 1535
8.44 Ozone in Gas 1536
Introduction 1536 Ozone Monitoring 1537 Monitor Designs 1537
Ultraviolet Analyzer 1537 Single-Beam Design 1537 Double-Beam Design 1537
Amperometric Design 1538 Calibration 1539
Thin-Film Semiconductor Design 1539 References 1539 Bibliography 1539
8.45 Ozone in Water 1540
Introduction 1541 Drinking Water Disinfection 1541
Amperometric Sensors 1541 Bare Metal Electrodes 1541 Membrane-Type Designs 1541
Stripping and Gas Phase Monitors 1542 Ultraviolet Absorption 1542 Colorimetric Method 1542
The Indigo Method 1542 References 1543 Bibliography 1543
8.46 Particulates, Opacity, Dust, and Smoke 1544
Introduction 1545 Definitions and Theoretical Concepts 1545
Opacity Measurement 1546 Units and Definitions 1546
Dust Loading 1546 Ringelmann Card Numbers 1547
Stack Gas and Particulate Monitoring 1547 Particulate Sampling 1547 Stack Gas Monitoring Packages 1547 Light Attenuation and Transmissometers 1547
Single-Pass Configuration 1548 Double-Pass Configuration 1549 Relative Performance 1550
Optical Divergence 1551 Spectral Characteristics 1551 Optical Characteristics 1551
Air Purge 1551 Manual Stack Samplers 1551
Automatic Stack Samplers 1552 Broken Bag and Runway Visibility
Sensors 1552 Ambient Air Opacity Monitoring 1552
Particulate Concentration 1552 High-Volume Sampler 1553
EPA Air Quality Goals 1553 Dichotomous Sampler 1553 Tape Sampler 1554
Soiling Index 1555 Light Scattering 1555
Nephelometers 1555 Piezoelectric Crystal Mass Balance 1555 Impaction Devices 1555
Calibration 1556 Radiometric Devices 1556 Charge Transfer (Triboelectricity) 1556 Surface Ionization 1556 Visual Observation 1556 Remote Sensing 1557
Conclusions 1557 References 1557 Bibliography 1557
8.47 Particle Size and Distribution Monitors 1559
Introduction 1560 Particle Size and Distribution 1560
Application Objectives 1560 Detectors and Sampling Systems 1560
Laboratory Monitors 1561 Sensing Small Samples 1561
Optical Microscopy 1561 Electron Microscopy 1561 Image Analyzers 1561 Electrical Sensing (Coulter Principle) 1561 Optical Scattering (Single Particle) 1561
Sensing Intermediate Samples 1561 Light Scattering (Multiple Particle) 1561 Sedimentation (Photo and X-Ray) 1561
Sensing Large Samples 1562 Sieving 1562 Optical Methods 1562 Ultrasonic Attenuation 1562
On-Line Measurement 1562 Optical Multiple-Particle Analyzer 1562 Airborne-Particulate Counter 1563
Bibliography 1563
8.48 pH Measurement 1565
Introduction 1566 Measurement Error 1566 Measurement Range 1566 Applications 1566
Theoretical Review 1567 Ion Concentrations 1567
pH Measurement 1568 Temperature Effects 1569 pH Electrodes and Sensors 1569
Flat Glass Electrodes 1569 Glasteel 1570 Metal Oxide pH Electrodes 1570 Ion-Selective Field Effect Transistors 1572
Fiber-Optic pH Measurement 1573 Relative Performance of pH Sensors 1573
Reference Electrodes 1573 Flowing and Double Junctions 1574 Combination Measurement/Reference
Electrode 1574 Multiple Junction References 1575 Stiff Gel Reference 1575 Differential Reference 1575
Electrode Cleaners 1576 Shrouds and Filters 1576 Automatic Cleaners 1576
Ultrasonic Cleaners 1577 Brush Cleaners 1577 Water-Jet Cleaners 1577 Chemical Cleaners 1577 Automatic Retraction 1578 Manual Cleaning 1578
Application Problems 1578 High Salt Errors 1578
High Salt Effect on Electrodes 1579 High Acid Errors 1579 Temperature Errors 1579 Water Concentration Errors 1580 Nonaqueous Solutions 1580 Probe Coating and Low Conductivity 1580
Installation Methods 1581 Submersion Assemblies 1581 Retractable Units 1581 Median Selector 1582 Self-Diagnostics 1582
Glass Impedance Measurements 1582 Reference Electrode Impedance 1583 Sensor Fault Signaling 1583
Calibration 1583 Buffer Calibration Errors 1583
Conclusion 1583 References 1584 Bibliography 1584
8.49 Phosphorus Analyzer 1585
Introduction 1585 Phosphorus in Wastewater 1585
Colorimetric Analysis 1586 Laboratory Methods 1586 Continuous Analyzer 1586 Total Phosphates 1586
Flame Photometric Analysis 1587 Detector Operation 1587
Gas and Liquid Chromatography 1587 Sample-Handling Systems 1587 References 1588 Bibliography 1588
8.50 Physical Properties Analyzers-ASTM Methods 1589
Introduction 1590 Advantages of Continuous Analyzers 1590
Distillation Analyzers 1590 Laboratory Measurements 1590
ASTM Method D 86-IP-123 1590 ASTM Method D 1160 1590 ASTM Methods D 2887-89, D 3710-88 1592
On-Line Distillation Analyzers 1592 End-Point Distillation Analyzers 1592 Vacuum Distillation Analyzer 1593 Horizontal Still Distillation Analyzer 1594 Simulated Distillation by Gas
Chromatography 1595 Calibration and Sampling 1595 Applications 1595
Vapor Pressure Analyzer 1595 Reid Method (ASTM Method D 323-90)
Procedure A 1595 Dry Reid Method (ASTM Method
D 4953-90) 1596 Liquefied Petroleum Gases (ASTM
Method D 1267-89) 1596 Air-Saturated Vapor Pressure
Analyzer-Continuous 1596 Air-Saturated Vapor Pressure
Analyzer-Cyclic 1596 Dynamic Vapor Pressure Analyzer 1596 Calibration 1597 Application 1597
Vapor-Liquid Ratio Analyzers 1598 Volatility Test (ASTM Method D
2533-90) 1598 Continuous Vapor-Liquid Ratio Analyzer 1598 Calibration and Application 1598
Pour-Point Temperature Analyzers 1599 Pour-Point Test (ASTM Method D
97-87) 1599 Pour Point by Differential Pressure 1599 Viscous-Drag Pour Pointer 1600 Calibration 1600 Application 1600
Cloud-Point Analyzers 1600 Cloud-Point Tests (ASTM Method D
2500-88) 1600 Optical Cloud-Point Analyzer 1601 Calibration and Application 1601
Freezing-Point Analyzer 1601 Aviation Fuel Tests (ASTM
Method D 2386-88) 1601 Freezing-Point Analyzer for Aviation Fuel 1602 Calibration and Application 1602
Flash-Point Analyzer 1602
Flash-Point Tests (ASTM Methods D 56-90 and D 93-90) 1602
Low-Temperature Flash-Point Analyzer 1602 High-Temperature Flash-Point Analyzer 1603 Calibration and Application 1603
Octane Analyzers 1603 Laboratory Tests (ASTM Methods D-2699 and
D-2700) 1603 Standard Engine Octane Comparator
Analyzer 1603 Reactor-Tube Continuous Octane Analyzer 1604 Calibration and Application 1604
Near-Infrared Analyzers 1604 Chemometrics 1604 Calibration and Application 1604
Bibliography 1605
8.51 Raman Analyzers 1606
Introduction 1607 Principles of Raman Spectroscopy 1607
Optical Spectroscopy 1607 Principles of Raman Scattering 1607 Raman Scattering and Spectral
Information 1607 General Instrumentation 1609
Fourier Transform Raman Instrumentation 1610 Dispersive Raman Instrumentation 1610
Raman Process Analyzer Instrumentation 1611 Components of Raman Process Analyzers 1611
Laser Excitation Source 1611 Spectrometer 1612 Detector 1612 Fiber Optic Light Delivery and
Collection 1612 Laser and Raman Filters 1613 Sample Interface 1613 Raman Probes 1613
Data Analysis, Modeling and Calibration 1614 Polymerization Application 1614 Multivariable Predictive Analysis 1614 Calibration Model 1614 Calibration Transfer 1615
Smart Diagnostics and Analyzer Maintenance 1616
Laser Safety 1616 Outputs and Communication 1616 Packaging 1616
Installation and Maintenance 1616 Probe Designs 1616
Advantages and Disadvantages 1617 Advantages 1617 Limitations 1618
Applications 1618 Polymer Industry 1618
Conclusion 1618 References 1619 Bibliography 1619
8.52 Refractometers 1620
Introduction 1621 RI and Brix Units 1621
Theory of Operation 1621 Critical Angle of Refraction 1622
Differential Refractometer 1623 Single-Pass Design 1623 Two-Pass Design 1623
Temperature Effects 1624 Flowing Reference Cell 1624
Critical-Angle Refractometer 1624 Mounting and Compensation 1624 Design Variations 1624
Reflected Light Measurement 1624 Fiber Optic Probe 1625
Capabilities and Limitations 1625 Conclusions 1626 Bibliography 1626
8.53 Rheometers 1628
Introduction 1628 Reasons for Using Rheometers 1628 Dynamic Mechanical Analysis 1629
Tests to Distinguish Liquids from Solids 1629 Shear-Strain Tests 1629 Stress-Controlled Tests 1630 Nonlinear Shear Flow Properties (
µ
, N
,
N
) 1630 Rheometer Selection 1630 Rheometer Designs 1630
Cone-and-Plate Design 1630 Shear Flow Properties 1631 Torque Ranges 1631 Rheometer Selection 1632 Experimental Difficulties 1632 Dynamic Mechanical Analysis 1632 Linear Viscoelastic Shear Moduli
G
′
, G
″
1632 Molecular Weight Distribution 1633 Time-Temperature Superposition 1633 Conversion Among Rheological
Properties 1634 Parallel-Disc Design 1634
Parallel-Disc Geometry 1634 Limitation 1634
Rectangular Torsion Design 1634 Coaxial-Cylinder Design 1635
Tension/Compression and Bending Designs 1635
Extensional Flow Rheometer 1635 Extensional Viscosity Detectors 1636
Capillary Rheometers 1636 Conclusions 1636 Bibliography 1636
8.54 Streaming Current or Particle Charge Analyzer 1637
Introduction 1637 Operating Principles 1637
The Streaming Current 1637 Calibration 1638 Applications 1638
Treatment Chemical Selection 1638 Sampling 1639 Control System 1639
Conclusions 1639 References 1639 Bibliography 1640
8.55 Sulfur-in-Oil Analyzers 1641
Introduction 1641 X-Ray Absorption Analyzer 1641
Method of Operation 1642 X-Ray Fluorescence 1642 Pulsed UV Fluorescence 1642 Fuel Analysis Spectrometer 1645 Bibliography 1645
8.56 Sulfur Oxide Analyzers 1646
Introduction 1647 Applications 1647
Industrial Analyzers 1648 Stack Sampling 1648 Nondispersive Infrared 1648 Ultraviolet 1649 Correlation Spectrometry 1649 Thermal Conductivity 1650
Ambient-Air Analyzers 1650 Ambient-Air Sampling 1650 Calibration 1650 Colorimetric Analyzers 1650 Conductimetric Analyzers 1650 Coulometric Analyzers 1651 Flame Photometric Analyzers 1651 Electrochemical Analyzers 1652
References 1652 Bibliography 1652
8.57 Thermal Conductivity Detectors 1653
Introduction 1653 Thermal Conductivity 1653
Measurement Ranges 1654 The TCD Analyzer 1654
Main Components 1654 The Detectors 1654 The TCD Cells 1655 Bridge Circuits 1656 Temperature Control 1656
Operation 1656 The Reference Filament 1657
Packaging and Calibration 1657 Limitations 1657
Hydrogen in Hydrocarbons 1657 Conclusions 1657 Bibliography 1657
8.58 Total Carbon Analyzers 1658
Introduction 1659 Advantages and Limitations 1659 Carbon Measurement Techniques 1659 Analyzer Development 1659 Official Methods of TOC Determination 1659
Detector Types 1659 Nondispersive Infrared (NDIR) Analyzers 1659
High-Temperature Combustion 1660 Wet Chemical Oxidation 1660 Inorganic Carbon 1661 Automatic On-Line Design 1661
Aqueous Conductivity 1662 On-Line Conductivity 1662
Coulometric Analysis 1662 Colorimetric Analysis 1662 Flame Ionization Detector 1663
References 1664 Bibliography 1664
8.59 Toxic Gas Monitoring 1666
Hazardous and Toxic Atmospheres 1667 Safety Instrument Performance Standards 1667 Types and Levels of Toxicity 1668 Extreme Toxicity 1668
Toxic Gas Measurement 1668 Related Sections 1668
Continuous Sensor Designs 1668 Chromatography 1670 Spectrometers 1671 Radon Detectors 1671 Electrochemical Sensors 1671
Oxygen Detectors 1671 Amperometric Toxic Sensors 1672 Number of Electrodes 1672 Sensor Compensation and Life 1672
Fixed Detectors 1673 Portable Detectors 1674
Discontinuous Dosage Sensors 1674 Color Change Badges 1674
Continuous Color-Change Monitor 1674 Color Detector (Dosimeter) Tubes 1674 Sorption-Type Dosimeters 1675
Passive Personal Dosimetry 1675 Active or Dynamic Sampling 1676 Liquid and Solid Fillings 1676
Calibration 1677 Dynamic Calibrators 1678
Bubbler/Dilution Calibrator 1678 Electrochemical Calibrating Gas
Generators 1678 References 1678 Bibliography 1679 Web Links to Government Agencies 1679
8.60 Turbidity, Sludge, and Suspended Solids 1680
Introduction 1681 Light Absorption and Scattering 1681 Units of Turbidity 1681
Conversion among Turbidity Units 1681 Turbidity Analyzer Designs 1682
Forward-Scattering or Transmission Type 1682 Dual-Beam Design 1682 Laser-Type Meter 1683 Suspended Solids and Sludge Density
Sensors 1683 Scattered Light Detectors
(Nephelometers) 1683 Probe Design 1684
Backscatter Turbidity Sensors 1684 In-Line Units 1685
Density-Based Sensors 1685 Conclusions 1686 Bibliography 1686
8.61 Ultraviolet and Visible Analyzers 1687
Introduction 1688 UV Absorption 1688
Theoretical Aspects 1689 The Radiation Spectrum 1689 The Beer-Lambert Law 1689
Calibration 1690 UV-Absorbing Compounds 1690
UV Absorption Spectrum 1690 Applications 1691
UV Analyzer Components 1691 Radiation Sources 1691
Broad and Discrete Line Sources 1692 Selecting the Measuring Wavelength 1692
The Monochromator 1692 The Measuring Cell 1693 Detectors 1693 Readouts 1693
UV Analyzer Designs 1693 Single-Beam Analyzer 1693 Split-Beam Analyzer 1694 Dual-Beam, Single-Detector Analyzer 1695 Dual-Beam, Dual-Detector Analyzer 1695 Flicker Photometer 1695 Photodiode Array Spectrophotometers 1696 Scanning Spectrophotometers 1697 Retroreflector Probes 1697
Visible and NIR Photometers 1698 Visible Photometers 1698 Near-Infrared Photometers 1698
Conclusions 1699 References 1699 Bibliography 1699
8.62 Viscometers-Application and Selection 1700
Introduction 1700 Theory of Viscous Behavior 1700 Stoke’s Law 1700
Hagan-Poiseuille Law 1701 Kinematic Viscosity 1701 Intrinsic Viscosity 1701 Non-Newtonian Fluids 1701
Newtonian Fluids 1702 Pseudoplastics 1702 Dilatant Fluids 1702 Plastic Solids 1702 Thixotropic Materials 1702 Rheopectic Substances 1702 Apparent Viscosity Readings 1702
Conversion among Units of Viscosity 1702 Kinematic Viscosity 1703
Viscometer Selection and Application 1703 Selection 1703 Applications 1705
Finished Product Specification 1705 Routine Laboratory Testing 1705 Scientific Research Study 1705 In-Line Process Control 1705
Terminology 1705 Bibliography 1706
8.63 Viscometers-Laboratory 1708
Introduction 1709 Laboratory Viscometer Designs 1709
Bubble-Time Viscometers 1709 Accuracy and Limitations 1711
Capillary Viscometers 1711 Using the Ostwald Viscometer 1711 Accuracy and Limitations 1711 Calibration 1711 Automatic Capillary Viscometer 1713 Intrinsic Viscosity and Molecular
Weight 1713 Mark-Houwink Equation 1714 Capillary-Extrusion Viscometer 1714 Design Variations 1715 Limitations 1715
Efflux-Cup Viscometers 1715 Saybolt Viscometer 1715 Ford Cups 1716 Zahn Cups 1716 Automatic Efflux Cup 1716
Falling-Ball Viscometers 1717 Manual Falling-Ball Unit 1717 Making the Measurement 1717 Calibration and Error Sources 1718 Automatic Falling-Ball Viscometer 1718
Falling-Needle Viscometer 1718 Rotational Viscometers 1718
Coaxial-Cylinder Viscometer 1718 Non-Newtonian Fluids 1719 Performance 1720 Cone-and-Plate Viscometer 1720 The Drive 1720 Oscillating Design 1721 Advantages and Precautions 1721
Oscillating Piston Viscometer 1721 Bibliography 1721
8.64 Viscometers-Industrial 1723
Introduction 1724 Capillary Viscometers 1724
Sensor for Newtonian Fluids 1724 Limitations 1726 Calibration 1726 Differential Pressure Type 1726
In-Line Design 1727 Dual-Capillary Design 1727 Pipe Section as Viscometer 1727
Backpressure Type 1727 Falling-Piston Viscometer 1728
Process Pressure-Operated Design 1728 Precautions 1729 Falling-Slug or Falling-Ball Viscometers 1729
Float Viscometers 1730 Precautions 1730 Single-Float Design 1730 Two-Float Design 1731 Concentric Design 1731
Oscillating Viscometers 1732 Oscillating Blade 1732 Oscillating Piston 1732 Torsional Oscillation Design 1734
Plastometers 1734 Plastic Behavior 1735 Cone-and-Plate Plastometer 1735
The Unit of Mooney 1735 Kneader Plastometer 1735 Capillary Plastometer 1736
Advantages 1736 Limitations 1737
Rotary Viscometers 1737 Rotary Spindle Design 1737
Installation 1737 Performance 1738
Magnetically Coupled Viscometer 1738 Gyrating-Element Viscometer 1738 Agitator Power 1739 Double-Cylinder Viscometer 1739
Vibrating-Reed Viscometer 1739 Performance 1740 Installation and Calibration 1741
Coriolis Mass Flow Meter 1741 Measuring Tube Torsional Movement 1741
Conclusions 1742 Bibliography 1742
8.65 Water Quality Monitoring 1744
Introduction 1744 Categories of Monitors 1744
Monitoring for General Use 1744 Regulatory Compliance Monitoring 1745 Industrial Monitoring 1745
Monitoring System Components 1745 Sampling Systems 1745
Duckbill Samplers 1745 Sample Transport 1746
Sensors and Analyzers 1747 Water Quality Parameters 1747 Ion-Selective Electrodes 1747
Conductivity 1749
pH Measurement 1749 Oxidation-Reduction Potential 1749
Oxygen Demand Detectors 1749 Dissolved Oxygen Sensors 1750 Total Organic Carbon and Total Carbon
Analyzers 1750 Turbidity Meters 1750 Nephelometers 1750 Wet Chemistry and Autotitration 1750 Volatile Organics 1751
VOC Compounds of Interest 1751 Chromatographs 1752
Sample Obtained by Sparging 1752 Temperature and Environmental Variables 1752
Unattended Monitoring Stations 1753 References 1753 Bibliography 1753
8.66 Wet Chemistry and Autotitrator Analyzers 1755
Introduction 1755 Automatic Titration 1755
Types of Reactions and End-Point Detectors 1755
Continuous and Batch Designs 1756 Volumetric Analyzers 1756
High-Precision Volumetric Analyzer 1756 Operating Sequence 1756 Multiple End Points 1757
Simple Volumetric Analyzer 1757 Applications of Volumetric Analyzers 1758
Colormetric Analyzers 1758 High-Precision Colorimetric Analyzers 1759
Use of Gas Bubbles 1759 Split-Beam Colorimeter 1759 Calibration 1759
Simple Colorimetric Analyzers 1760 Calibration 1760
On/Off Batch Colorimeters 1760 Applications of Colorimetric Analyzers 1761
Flow Injection Analysis 1761 Laboratory FIA 1761 Industrial FIA 1762 Application Example 1 1762 Application Example 2 1762
Calibration 1763 References 1763 Bibliography 1763
INTRODUCTION
Modern process control requires current information on the state (composition, temperature, pressure, flow rate, etc.) of the material being produced. Modern distributed control systems linked to various control elements (valves, pumps, etc.) require data much more often than the manual control systems of years gone by. While grab samples taken to a modern laboratory will be the gold standard for quality control purposes, the effort and time it takes to get a sample, transport it to the lab, and wait for the result can add significantly to the costs of the process in process output, energy, etc. For many industries, the solution is to move the analysis directly to the process.
