Abstract
The application of secondary NOx control methods in medium to low-capacity furnaces is a relatively new topic on the energy market and thus requires further research. In this paper, the results of full-scale research of SNCR and hybrid SNCR + SCR methods applied into a 29 MWth solid fuel fired stoker boiler is presented. The tests were performed for a full range of boiler loads, from 33% (12 MWth) to 103% (30 MWth) of nominal load. A novel SNCR + SCR hybrid process was demonstrated based on an enhanced in-furnace SNCR installation coupled with TiO2-WO3-V2O5 catalyst, which provides extra NOx reduction and works as an excess NH3 “catcher” as well. The performance of a brand-new catalyst was evaluated in comparison to a recovered one. The emission of NOx was reduced below 180 mg NOx/Nm3 at 6% O2, with ammonia slip in flue gas below 10 mg/Nm3. Special attention was paid to the analysis of ammonia slip in combustion products: flue gas and fly ash. An innovative and cost-effective method of ammonia removal from fly ash was presented and tested. The main idea of this method is fly ash recirculation onto the grate. As a result, ammonia content in fly ash was reduced to a level below 6.1 mg/kg.
Highlights
Nitrogen oxides NO and NO2 emitted from power units are claimed to significantly contribute to the formation of numerous environmental pollutants, such as acid rain, haze, or smog
Denitrification processes was successfully performed in a stoker boiler for the full range of power output
The Furnace Jet Boiler System (FJBS) installation was combined with the TiO2 -WO3 -V2 O5 catalyst to create the hybrid selective non-catalytic reduction (SNCR) + selective catalytic reduction (SCR) system FJBS+
Summary
Nitrogen oxides NO and NO2 (known together as NOx ) emitted from power units are claimed to significantly contribute to the formation of numerous environmental pollutants, such as acid rain, haze, or smog. The technologies of selective catalytic reduction (SCR). Selective non-catalytic reduction (SNCR) are commonly implemented to reduce NOx emissions in the power sector [1,2]. Their effectiveness is based on the reaction of nitrogen oxides with ammonia or urea compounds. It can be potentially used to reduce the NOx emission from power plants and waste combustion units but other stationary sources as well (e.g., chemical and metallurgical industry) [12,13,14]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
