| Abstract Title: | Testing equivalency of alternative methods for monitoring of so2 emissions |
| Session Choice: | Calibration and Quality Control |
| Presenter Name: | Ms Tuula Pellikka |
| Co-authors: | Ms Tuula Kajolinna |
| Company/Organisation: | VTT Technical Research Centre of Finland |
| Country: | Finland |
Abstract Information :
Euramet launched year 2016 Sulf-Norm project "Metrology for sampling and conditioning SO2
emissions from stacks". The overall aim of this project is to compare conditioned sampling
approaches to the unconditioned sampling approach associated with the existing standard
reference method, SRM (EN 14791).
Standard Reference Method, EN 14791, that is used at the moment in Europe for the
measurement of SO2 is based on wet-chemical measurement method. A sample of gas is
extracted via a heated temperature-controlled probe. The sample is filtered and drawn through
hydrogen peroxide absorber solutions for a specified time and at a controlled flow rate. The SO2 in
the sampled gas is absorbed and oxidised to sulphate ion which is determined either using ion
chromatography or by titration with a barium perchlorate solution using Thorin as indicator.
As part of the Sulf-Norm-project, VTT Technical Research Centre of Finland organized in the
spring 2017 tests for equivalency of alternative methods for monitoring of SO2 emissions. The aim
of these experiments was to test whether alternative methods (AM) could be used to determine
SO2 concentrations instead of existing SRM. The advantage of using automated, instrumental
method is that they give real time information about the process concentrations where as wetchemical
method gives only average value of the sampling time. Instrumental methods that were
used in this test were Fourier Transform Infrared Technique analysers (FTIR), ultraviolet (UV)-
fluorescence analysers and non-dispersive infrared (NDIR) analysers.
Tests were carried out at the test bench of VTT. Exhaust gas was produced with engine
combusting gasoline. SO2-concentrations were varied by spiking of SO2 gas to the exhaust gas
flow and the concentration range varied from 2 ppm to 200 ppm. All together 25 samples were
taken. The results will be analysed using the principles given in the document TS 14793.
In this presentation, the results and the conclusions from these tests are presented.
