@ARTICLE{Zwierzchowski_Ryszard_Operational_2021, author={Zwierzchowski, Ryszard and Różycka-Wrońska, Ewelina}, volume={47}, number={3}, pages={108-119}, journal={Archives of Environmental Protection}, howpublished={online}, year={2021}, publisher={Polish Academy of Sciences}, abstract={This study describes the correlation between emission of gaseous pollutants to the atmosphere and the combustion parameters of a coal-fired 25 MW heating capacity water boiler with mechanical grate (boiler type WR-25) in unstable working conditions: start-up, shutdown and loads below the technical minimum. Whereas measurements were made for a specific type and size of coal-fired water boiler with mechanical grate, the measurements and calculations are applicable to WR boilers with a different heating power as well as OR type steam boilers, which have a practically identical design. In sum, there are more than 1,000 coal-fired water and steam boilers of these types in Poland. In addition, the analysis reported in this paper highlights the important role played by boilers operating in unstable conditions in terms of emission of gaseous pollutants to the atmosphere. The conclusions are relevant for other boilers fi red with gas, oil or biomass operating under conditions such as start-up, shutdown and loads below the technical minimum. This article fi lls a gap in air protection engineering practice and the literature with regard to indicators and emission standards, drawing on measurements of pollutant concentrations in the exhaust gases from unstable WR boiler working conditions. The measurements can be used to assess the emission of pollutants to the atmosphere in such boiler working conditions and their impact on air quality. The analyses presented were based on the authors’ own measurements in WR-25 boiler technical installations using portable gas analyser GASMET DX-4000, which uses the FT-IR measurement method for compounds such as SO2, NOx, HCl, HF, NH3, CH4, and CO. Concentrations of CO, NOx and SO2 in exhaust gases were determined with multiple regression with the STATISTICA statistical software and with linear regression complemented by the “smart” package in the MATLAB environment. The study provides computational models to identify pollutant concentrations in the exhaust gases in any working conditions of WR-25 boilers}, type={Article}, title={Operational determinants of gaseous air pollutants emissions from coal-fired district heating sources}, URL={http://journals.pan.pl/Content/120757/Archives%203_vol47_2021_pp108_119.pdf}, doi={10.24425/aep.2021.138469}, keywords={district heating, gaseous air pollutant emission, emission indicators, unstable conditions, heat onlyboilers}, }