Stack testing

Stack testing

Several EU directives and national laws in European countries set requirements for continuous monitoring of flue gas emissions at power plants. Further requirements are set on the quality assurance of the installed measurement systems at the plants. The relevant standard in this regard is EN 14181:2004, the quality assurance of automated measuring systems. The standard dictates how to determine that the measurement systems installed for continuous emissions monitoring at a plant operate according to the directives and regulations set. Two major parts of this on-going quality assurance cycle are the QAL2 and AST procedures. A test laboratory performs tests on the systems on-site and determines whether the systems fulfill the set requirements or not.

The Gasmet™ Portable DX4000 Multicomponent Gas Analyzer and its Portable Sampling System are tried and tested solution for the test laboratories that wish to make these tests. The system parts can be transported to the measurement location and assembled there for the measurements. The hot-and-wet extractive sampling combined with the FTIR measurement technique means that no special sample preparation is required in stack testing. The DX4000 analyzer and the Portable Sampling System combination has the coveted MCERTS certification from Sira Environmental for stack emissions monitoring. The system measures simultaneously a great selection of the typically monitored gaseous emissions components:

  • H2O, CO and CO2
  • Nitrogen oxides (NOx, that is nitrogen monoxide NO and nitrogen dioxide NO2) and nitrous oxide N2O
  • Water-soluble components such as SO2, NH3, HF and HCl
  • Several hydrocarbons such as methane CH4, ethane C2H6, propane C3H8, and many others


Stack testing according to EPA test method 320

The United States Environmental Protection Agency (EPA) has two stack testing methods for FTIR gas analyzers. Method 320 is an FTIR method for measuring a wide range of organic and inorganic pollutants. Method 321 is a specific version for measuring hydrogen chloride HCl at cement kilns producing Portland cement. These methods define a quality assurance and control processes for verifying the accuracy of the results. The requirements for analytical equipment and software are defined in 40 CFR Part 60 Appendix B Performance Specification 15. Gasmet™ Gas Analyzers and Calcmet™ software have been designed to take the requirements of the performance specification into account.