NOx emission reduction by alternative fuels in the cement industry

Alternative fuels typically contain less fuel nitrogen than coal. Hence, fuel-NOx emissions may be reduced by switching from coal to RDF or other waste-based fuels.


Moreover, if the alternative fuel can be fed into the process in a fuel staging regime, then additional NOx reduction by reburning can be expected. This has been tested in full-scale processes, and up to 40 % NOx reduction has been demonstrated.

Waste fuels containing nitrogen in amine form may in some cases be used for NOx reduction through selective non-catalytic reduction (SNCR). The potential of using amine reclaimer wastes (ARW) from amine-based CO2 capture processes has been demonstrated.

References

Axelsen, E.P., Tokheim, L.A. and Bjerketvedt: "Investigation of NOx reduction during the combustion of alternative fuels", Zement-Kalk-Gips, 56, No. 4, 54-63, 2003

Axelsen, E.P., Tokheim, L.A. and Bjerketvedt, D.: "Effect of alternative fuel properties on NOx reduction", Conference proceedings, VDZ congress, Düsseldorf, 23-27 September 2002

Botheju, D., Glarborg, P.  and Tokheim, L.A.: "The use of amine reclaimer wastes as a NOx reduction agent", Energy Procedia, 2013

Botheju, D., Glarborg, P.  and Tokheim, L.A.: "NOx reduction using amine reclaimer wastes (ARW) generated in post combustion CO2 capture", International Journal of Greenhouse Gas Control, 10, No. 9, 33-45, 2012

Botheju, D., Glarborg, P.  and Tokheim, L.A.: "The use of amine reclaimer wastes as a NOx reduction agent", 11th International Conference on Greenhouse Gas Technologies (GHGT-11), Kyoto, Japan, 18-22 November, 2012

Botheju, D., Glarborg, P.  and Tokheim, L.A.: "Use of CO2 Capture Wastes for NOx Reduction in Flue Gas Streams", Climit seminar, Oslo, 28-29 November 2011

Svinning, K., Tokheim, L.A. and Bjerketvedt, D.: "Statistical analysis of the correlation between NOx emissions and production conditions in a cement kiln applying staged combustion", World Cement, 15, No. 1, 68-75, 1998

Tokheim, L.A., Botheju, D. and Glarborg, P.: "NOx Reduction Potential of Amine Reclaimer Waste Generated in Post Combustion CO2 Capture – Results from Work Package 4 under Climit project 199905 - CO2 capture from industrial point sources and further development of amine reclaimer waste handling by incineration and biological treatment (‘Industrial CCS’)", Climit Summit 2013, Oslo, 25-26 February 2013

Tokheim, L.A.: "The impact of staged combustion on the operation of a precalciner cement kiln", PhD dissertation, TUC/NTNU, 1999

Tokheim, L.A., Bjerketvedt, D., Husum, I. and Høidalen, Ø.: "NOx reduction in a precalciner cement kiln using plastic as reburning fuel", Zement‑Kalk‑Gips, 51, No. 1, 12‑23, 1998

Tokheim, L.A. and Bjerketvedt, D.: "NOx reduction by staged combustion in a precalciner cement kiln using alternative fuels", Work-in-progress poster no. 1G18, Symposium (International) on Combustion, 27, The Combustion Institute, USA, 1998