Abstract
This study focuses on a CFD modelling of biomass-derived syngas co-firing with coal in an older mid-sized PC-fired boiler of type OP-230 with low-emission burners on the front wall. The simulations were performed to determine whether the boiler can be retrofitted for the fulfilment of the prospective environmental protection regulations relating to levels of NOX emissions. The improvement of the air staging via the dual-fuel technique was based on the indirect co-firing technology. The impact of two arrangements of dedicated syngas nozzles (below and above the existing coal burners), two syngas compositions and two heat replacements (5% and 15%) on the course of thermal processes in a furnace was tested. The reductions in NOX emissions were predicted relative to the baseline when only coal is combusted. The highest reduction of about 38% was achieved with the syngas nozzles below the existing coal burners and 15% heat replacement. This arrangement of nozzles offers the residence time sufficient to co-fire coal with waste derived syngas. A lower reduction in NOX emissions was obtained with the nozzles above the burners as the enlargement of local fuel rich zone near syngas injection becomes significant for 15% heat replacement. Results provide for the decreasing impact of methane content along with the increase of syngas heat input. The avoided CO2 emissions through the syngas indirect co-firing with coal in the boiler are linear function of heat replacements.
Similar content being viewed by others
References
Zhou C., Wang Y., Jin Q., Chen Q., Zhou Y., Mechanism analysis on the pulverized coal combustion flame stability and NOX emission in a swirl burner with deep air staging, Journal of the Energy Institute, in print, 2018, https://doi.org/10.1016/j.joei.2018.01.006.
Chen S., He B., He D., Cao Y., Ding G., Liu X., Duan Z., Zhang X., Song J., Li X., Numerical investigations on different tangential arrangements of burners for a 600 MW utility boiler, Energy, 2017, 122: 287–300.
Watts J.U., Mann A.N. and Russel D.L., An overview of NOX control technologies demonstrated under the department of energy’s clean coal technology program, U.S, Department of Energy, Federal Energy Technology Center, 2000.
Holland C.D., A summary of NOX reduction technologies, texas institute for advancement of chemical technology, 2002.
ANSYS® Academic Research Fluent Manual, Release 18.
Adamczyk W.,P., Werle S., Ryfa A., Application of the computational method for predicting NOX reduction within large scale coal-fired boiler. Applied Thermal Energy, 2014, 73: 343–350.
Wu K.T., Lee H.T., Juch C.I., Wan H.P., Shim H.S., Adams B.R., Chen S.L., Study of syngas co-firing and reburning in a coal fired boiler, Fuel, 2004, 83: 1991–2000.
Dong C., Yang Y., Yang R., Zhang J., Numerical modeling of the gasification based biomass co-firing in a 600MW pulverized coal boiler, Applied Energy, 2010, 87: 2834–2838.
Kalisz S., Pronobis M., Baxter D., Co-firing of biomass waste-derived syngas in coal power boiler, Energy, 2008, 33: 1770–1778.
Valler K., Wopera A., Palotas A.B., Whitty K.J., NOX formation by synthesis gas–natural gas co-firing, 4th European Combustion Meeting, ECM, Vienna, Austria, 2009: 14–17.
Toporov D., Bocian P., Heil P., Kellermann A., Stadler H., Tschunko S., Förster M., Kneer R., Detailed investigation of a pulverized fuel swirl flame in CO2/O2 atmosphere, Combustion and Flame, 2008, 155: 605–618.
Chen L., Yong S.Z., Ghoniem A., Oxy-fuel combustion of pulverized coal: characterization, fundamentals, stabilization and CFD modeling, Progress in Energy and Combustion Science, 2012, 38: 156–214.
Crnomarkovic, N., Belosevic, S., Tomanovic, I. et al., Weighted sum of gray gases model optimization for numerical investigations of processes inside pulverized coal-fired furnaces, Journal of Thermal Science, 2017, 26: 552–559.
Chacartegui R., Torres M., Sánchez D., Jiménez F., Muñoz A., Sánchez T., Analysis of main gaseous emissions of heavy duty gas turbines burning several syngas fuels, Fuel Process. Technol., 2011, 92: 213–220.
Askarova, A., Bolegenova, S., Maximov, V. et al., Numerical modeling of pulverized coal combustion at thermal power plant boilers, Journal of Thermal Science, 2015, 24: 275–282.
Acknowledgements
Research have been carried out in the framework of 3190/23/P and S/WZ/1/2015 works financed by Ministry of Science and Higher Education of Poland from the funds for science.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Motyl, P., Łach, J. Computational Modelling of Retrofitting a Coal Fired Boiler Type OP-230 for Predicting NOX Reduction. J. Therm. Sci. 27, 433–439 (2018). https://doi.org/10.1007/s11630-018-1037-9
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11630-018-1037-9