Flue gas analyzers play a very important role in the field of environmental chemistry today. Flue gas is the by product of high temperature combustion boilers used in cracking and refining. Flue gas is of particular interest to environmental chemists due to the fact that it has several components or chemicals in it that can potentially harm the environment if released unchecked. As a means to keep tabs on flue gas effluent, flue gas analyzers are positioned so as to keep close tabs on the components and concentration of components found in flue gas.
Upon analysis, flue gas can be found to contain compounds such as but not limited to: methane, ethane, ethylene, propane, propylene, n-butane, isobutane, trans-2-butene, 1-butene, isobutylene, cis-2-butene, 1-pentene, 3-methyl-1-butene, 2-methyl-2-butene, methyl acetylene, propadiene, 1,3-butadiene, 1-hexene, n-hexane and a whole host of C6+ compounds. Additionally, you may find poisonous and toxic gases such as hydrogen sulfide, SOx gases such as Sulfur Dioxide and NOx gases such as Nitrogen Dioxide.
As far as the major components in flue gas are concerned, a flue gas analyzer does a great job of breaking down the components and their concentrations for reporting to environmental authorities as required. A powerful flue gas platform will generally be based around an Agilent platform, namely a gas chromatograph, containing several columns, switching and sampling valves as well as the appropriate detectors so as to detect the compounds of interest.
For example, a complete flue gas analyzer will contain an Aluminum Plot capillary column for analyzing all of the hydrocarbons such as methane, ethane, ethylene, propane, propylene, n-butane, isobutane, trans-2-butene, 1-butene, isobutylene, cis-2-butene, 1-pentene, 3-methyl-1-butene, 2-methyl-2-butene, methyl acetylene, propadiene, 1,3-butadiene, 1-hexene, n-hexane and a whole host of C6+ compounds. This column would be coupled with a Flame Ionization Detector. Additionally, you will have both Mole Sieve and Porpaq-Q columns for the analysis of fixed gases such as hydrogen , helium, carbon dioxide, ethane, ethylene, acetylene, argon/oxygen, nitrogen, methane, carbon monoxide to name a few. These columns would be coupled with a Thermal Conductivity Detector. Finally, high end, specialty flue gas or refinery gas analyzers can also have specialty detectors such as Sulfur or Nitrogen Chemiluminescence detectors added for the detection of SOx and NOx gases.
Analysis would take place about every fifteen minutes for accurate tracking and reporting which can be done automatically via the internet with current technology.