Testing equivalency of an alternative method based on portable FTIR to the European Standard Reference Methods for monitoring emissions to air of CO, NO_x, SO₂, HCl, and H₂O

Abstract

We compare the performance of an alternative method based on portable Fourier-transform infrared (FTIR) spectroscopy described in TGN M22, "Measuring Stack Gas Emissions Using FTIR Instruments," to the Standard Reference Methods (SRMs) for CO (EN 15058), NOx (EN 14792), SO₂(EN 14791), HCl (EN 1911), and H₂O (EN 14790). Testing was carried out using a Stack Simulator facility generating complex gas matrices of the measurands across concentration ranges of 0-75 mg m⁻³ and 0-100 mg m⁻³ CO, 0-200 mg m⁻³ and 0-300 mg m⁻³ NO, 0-75 mg m⁻³ and 0-200 mg m⁻³ SO₂, 0-15 mg m⁻³ and 0-60 mg m⁻³ HCl, and 0-14 vol% H₂O. The former values are the required monitoring range for each measurand as described in the European Union (EU) Industrial Emissions Directive (2010/75/EU) for waste incineration processes, and the latter are supplementary ranges representative of emissions from some large combustion plant processes. Test data were treated in accordance with CEN/TS 14793, and it was found that equivalency test criteria could be met across all concentration ranges with the exception of the NO supplementary range. The results demonstrated in principle where TGN M22/FTIR could be used in place of the existing SRMs to provide, as required under the Industrial Emissions Directive, annual validation/calibration of automated measuring systems (AMSs being permanently installed on industrial stacks to provide continuous monitoring of emissions to air). These data take a step toward the wider regulatory acceptance of portable FTIR providing the advantages of real-time calibration and quantification of all measurands on a single technique.

SO2 emission measurement with the European standard reference method, EN 14791, and alternative methods – observations from laboratory and field studies

“…Based on earlier studies (Vahlman and Larjava 1990), condensation methods have the tendency to absorb SO 2 into the condensate, and their use is thus not recommended if the measured It is also seen that the AMs usually seem to have a better repeatability than the wet-chemical based SRM, EN 14791, with the exception of the NDIR-based measurement set-up. This same phenomenon has been observed also in earlier studies (Coleman et al 2015).…”

Long-path measurements of pollutants and micrometeorology over Highway 401 in Toronto

“…FTIR spectroscopy has been used to quantify the mixing ratios of various trace species emitted by forest biomass burning (Griffith et al, 1991;Yokelson et al, 1996Yokelson et al, , 1997Yokelson et al, , 2007Yokelson et al, , 2008Yokelson et al, , 2013Goode et al, 1999;Burling et al, 2010;Johnson et al, 2010;Akagi et al, 2013Akagi et al, , 2014Paton-Walsh et al, 2014;Smith et al, 2014), volcanoes (Horrocks et al, 1999;Oppenheimer and Kyle, 2008), industrial parks (Wu et al, 1995), and in urban areas Hong et al, 2004;Coleman et al, 2015). FTIR spectroscopy was also used in flux measurements by the gradient technique at agriculture sites (Griffith and Galle, 2000).…”

Uncertainty requirements of the European Union’s Industrial Emissions Directive for monitoring sulfur dioxide emissions: Implications from a blind comparison of sulfate measurements by accredited laboratories

“…As mentioned in Introduction, an alternative method can be used in place of the SRM for compliance and QAL2 calibration purposes if equivalency data produced in accordance with CEN/TS 14793 are accepted by the national regulator. The word "equivalency" is the key point here, i.e., the studies to date involving portable Fourier transform infrared (FTIR) spectroscopy, nondispersive infrared spectroscopy, infrared gas filter correlation, electrochemical cell, and ultraviolet (UV) absorption (Coleman et al 2015(Coleman et al , 2010 have shown evidence of "equivalence." However, equivalent performance arguably is not enough, and what is needed is evidence of improved performance, as what is clear is that ELVs are becoming increasingly stringent.…”

“…It is not always mandatory to use the SRM, and a national regulator may permit the use of an alternative method (AM) if it has been demonstrated to produce equivalent data to the SRM in accordance with CEN/TS 14793: "Stationary Source Emission-Intralaboratory Validation Procedure for an Alternative Method Compared to a Reference Method" (CEN 2005b). An example of this has been reported previously where a UK method based on portable Fourier transform infrared spectroscopy (Environment Agency for England [EA] 2012b) was shown to produce equivalent data to the SRM for SO 2 and some other key pollutants (Coleman et al 2015). However, it should be noted that there is something of a split across Europe in that some national regulators permit the use of AMs whereas others do not.…”