Applicability of Secondary Denitrification Measures on a Fluidized Bed Boiler

Jitka Jeníková; Kristýna Michaliková; František Hrdlička; Jan Hrdlička; Lukáš Pilař; Matěj Vodička; Pavel Skopec

doi:10.14311/AP.2022.62.0341

Authors

Jitka Jeníková Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Energy Engineering, Technická 4, Prague 6, Dejvice, 160 00, Czech Republic
Kristýna Michaliková Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Energy Engineering, Technická 4, Prague 6, Dejvice, 160 00, Czech Republic
František Hrdlička Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Energy Engineering, Technická 4, Prague 6, Dejvice, 160 00, Czech Republic
Jan Hrdlička Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Energy Engineering, Technická 4, Prague 6, Dejvice, 160 00, Czech Republic
Lukáš Pilař Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Energy Engineering, Technická 4, Prague 6, Dejvice, 160 00, Czech Republic
Matěj Vodička Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Energy Engineering, Technická 4, Prague 6, Dejvice, 160 00, Czech Republic
Pavel Skopec Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Energy Engineering, Technická 4, Prague 6, Dejvice, 160 00, Czech Republic

DOI:

https://doi.org/10.14311/AP.2022.62.0341

Keywords:

SCR, SNCR, fluidized bed boiler, denitrification, deNOx, coal

Abstract

This article compares performance of selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR) applied on the same pilot unit, a 500 kW fluidized bed boiler burning Czech lignite. Correlation of the denitrification efficiency on the normalized stoichiometric ratio (NSR) is investigated. The fundamental principle of the SCR and SNCR is similar with the same reaction scheme. The difference is in the use of the catalyst that lowers the activation energy of the key reaction. As a result, the reduction is performed in the SCR method at lower temperatures. During experiments, the NSR was up to 1.6 for the SCR method. For the SNCR method, which has a higher reducing agent consumption, maximum denitrification efficiency was reached for NSR about 2.5. The efficiency of both secondary methods was investigated. The denitrification efficiency during experiments exceeded 98 % for the SCR method, and the SNCR method, together with the primary measures, reached an efficiency of 58 %.

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