Analyzer Selection USING THE ORIENTATION TABLE

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1 Analyzer Selection Selecting the right analyzer for a particular application requires that we follow a sequence of logical steps: 1.Clearly defining the purpose of the analyzer. 2.Determining if a continuous on-line analyzer is needed or an intermittent, grab sample based, laboratory analysis is sufficient. 3.For on-line units, the next step is to determine if the instrument can be removed for calibration or if automatic, on-line selfcalibration is needed. It is also desirable to resolve if the re-calibration should be triggered by self-diagnostics, operator initiation or time? 4.The next step is to determine if inline or off-line installation is needed? 5.If a probe type design is selected, should it be provided with means for self cleaning? 6.If a sampling system is to be used, what types of accessories are required for filtering, etc.? 7.Only after an in depth review of these questions, should the process control engineer decide on the type of analyzer to be used and on the types of accessories to be utilized. In order to quickly identify the types of analyzers to consider the use of an Orientation Table, such as the one below is useful. 8.Only after these steps should the specifications be prepared and sent out for competitive bidding. For the purpose of specification, one can use the analyzer specification form prepared by ISA (20A1001). 9. Once the bids are analyzed and the vendor is selected, the preparation of the installation drawings can start and the communication between the analyzer and its workstation or remote displays and/or controllers can be resolved. 10. The last step comes after installation and check-out, when the maintenance specifications are prepared. It is not uncommon to revise the specifications or the selection during the design phase when/if new information is obtained. This is normal and is a sign of good engineering, while the need to make changes after start-up is not. USING THE ORIENTATION TABLE This table should help to get oriented concerning the available options for a particular application. The ORIENTATION TABLE lists over a hundred components and some 28 analyzer categories. It indicates (by check marks), the analyzer types, which can detect the concentration of the component of interest. Once the suitable analyzer types been identified, the reader can consider their relative costs, inaccuracies, advantages and disadvantages. This information is provided on the front pages of the corresponding chapters in mt Instrument and Automation Engineers Handbook (IEAH), while the body of the chapters provides the detailed description of the particular analyzer.

2 ORIENTATION TABLE FOR ANALYZER SELECTION SUITED FOR THE Acetaldehyde Acetic Anhydride Acetone Acid in Water Acrylonitrile Alcohol in Water Aldehydes Alcalinity of Water Alkyl Chloride Aluminum Amines, ppm Ammonia Ammonium in Water Aniline Argon Aromatics Benzene Brine Bromide Bromine 1 For the proper operation of probe type analyzers, it is essential to keep them clean. For the available types of probe cleaner designs and their suppliers, refer to the IAEH.

3 SUITED FOR THE Butane Butadiene Cadmium Caffeine Calcium Carbon Disulfide Carbon Dioxide 2 A very wide range of materials can be analyzed by chromatgraphy. In that regard, the listing in this tabulatoin is rather incomplete, because while practically all materials listed could be so analyzed, economics usually limits the number of it s applications. 3 This category includes battery operated gas diffusion sensors, amperometric, (also referred to as galvanometric or polarographic), potentiometric and coulometric detectors., 4 This category includes UV and atomic fluorescent sensors. 5 This category of analyzers includes Raman, near infrared (NIR), non-dispersive infrared (NDIR),fourier transform infrared (FTIR), microwave and radio frequency type sensors. 6 TDLAS = Tunable Diode Laser Absorption 7 Includes neutron backscatter and NMR ( Nuclear Magnetic Resonance) 8 These are basically potentiometric sensors. ORP is the abbreviation of oxidation-reduction potential and ISE stand for ion-selective electrode. ph is also an ISE, which is sensitive to the activity of the hydrogen ion. 9 Crystal oscillator design 10 The refractiv indexes (RI) of a number or compounds are given in the IAEH. 11 Includes both thermal conductivity detectors (TCD) and heat of adsorption sensors. 12 Includes photometric and light reflection sensors. For a complete list of compounds that are absorbing within the range of UV and visible wavelengths, refer to the IAEH. 13 Includes chemiluminescence and titration type sensors. In case of an auto-titrator, the end point may be determined potentiometrically, conductimetrically, or photometrically.

4 SUITED FOR THE Carbon Monoxide Carbon Tetrachloride Caustic Chloride Ion Chlorine Chlorine Residual Chloroform Chromium in Water COD (Chem. O2 Dem.) Color Combustibles Copper in Water Cyanide in Water Cyclohexane Divalent Ions in Water Diolefin vapors Elements(all incl. Metals) Ethane Ethanol Ethyl Chloride &Bromide Ethylbenzene Ethylene Ethylene Glycol Ethylene Oxide

5 SUITED FOR THE Fluoride Freon Furfural Glycerine & Salt in Water Hardness (Water) Hazardous Gases Helium Hexane Hexavalent Chromium Humidity Hydrocarbons Hydrazine in Water Hydrocarbon in Air Hydrogen in Air or Steam Hydrogen Impurities Hydrogen Chloride, Bromide, Cyanide Hydrogen Sulfide Iodide Ions in Water Iron in Water Isobutane Isoprene Leads

6 SUITED FOR THE Lead Ions in Water Mercury in Air Mercury in Water Methane Methanol in Water Methyl Bromide,Chloride Methylene Chloride Moisture in Gases Moisture in Liquids Moisture in Solids 14 Nitrates in Water Nitric Acid in Water Nitric Oxide in Air Nitrogen Compounds Nitrogen Dioxide Nitrogen Oxide, Peroxide Nitrous Fumes Octane of Gazoline Oil in or on Water Olefins Oxygen in Water 15 (DO) 14 Analyzers using IR and NIR, microwave, Rf, neutron, capacitance, impedance, and electrical resistance techniques are applicable to the measurement of moisture in both solids and liquids.

7 SUITED FOR THE Oxygen in Gases Ozone in Gas Ozone in Water Particulates Phenol in Water Phosgene in Air Phosgene in Water Phosphoric Acid in Water Phosphate in Water Polymer-solvent Mix. Potassium in Water Propane Proteins Silicon in Paper Sodium Hydroxide in Water Sodium Ions in Water Solids (in Capsup, etc.) Steam in Air Sugar in Juice, Jam, Syrup 15 Also includes the measurement of biological, chemical and total oxygen demands (BOD, COD, and TOD). Total organic carbon (TOC) measurements give closely correlateable results to COD readings.

8 SUITED FOR THE Sulfates Sulfur in Oil Sulfur Dioxide Trioxide Sulfuric Acid Toluene in Hydrocarbons Total Carbon Total Nitrogen Toxic Gases Vinyl Chloride Xylenes in Hydrocrbons Naturally, because of space constraints, not all compounds of interest are listed in this table and not all categories and subcategories of analyzer types are separated into individual columns. For example, practically all substances can be analyzed by chromatography, but the cost of using chromatographs is so high that in most cases one would select a less expensive analyzer, which can also do the job. Similarly, in some columns I have combined several analyzer subcategories. For example under Electrochemical Analyzers I have included amperometric, coulometric, galvanometric, polarogrphic and potentiometric designs. Similarly, under Fluorescence I included a number of wavelengths (not only UV) and under Infrared I also included microwave, NDIR and other wavelengths. Similarly under Infrared I also included microwave, NDIR, and RF wavelengths, under Ultraviolet I also included photometric or light reflection designs or under Wet Chemistry I also included titration and chemicuminescence systems. In short, this Orientation Table is not as detailed or as complete as it could be, but it is more complete than any such table I have seen to date.