NOx formation in iron ore rotary kilns
Doctoral thesis, 2019
This thesis describes the NOx formation in the rotary kiln and identifies the governing parameters, with the aim of reducing the emissions. The work involves experiments in a pilot-scale kiln, as well as modeling work based on the same experiments. Data from a full-scale iron ore pelletization plant are also provided.
From the experiments and the modeling work in this thesis, thermal NO is deemed to be of low importance in iron ore rotary kilns when solid fuels are combusted. Instead, the conditions during char combustion contribute significantly to the overall NOx formation. These results explain why many of the primary measures used to date have failed to achieve reductions in NOx emissions. Suggested additional primary measures include: raising the pyrolysis temperature (e.g., through oxygen addition) to deplete the char of nitrogen; or switching to a fuel with a lower nitrogen content (e.g., wood pellets). These are interesting alternatives for the future, and the latter may be tested in the coming years.
Chalmers, Space, Earth and Environment, Energy Technology
Implications of Fuel Choice and Burner Settings for Combustion Efficiency and NOx Formation in PF-Fired Iron Ore Rotary Kilns
Energy & Fuels,; Vol. 31(2017)p. 3253-3261
Modeling the Contributions of Volatile and Char-Bound Nitrogen to the Formation of NOx Species in Iron Ore Rotary Kilns
Energy & Fuels,; Vol. 32(2018)p. 2321-2331
Scaling of Pulverized-Fuel Jet Flames That Apply Large Amounts of Excess Air - Implications for NOx Formation
Energies,; Vol. 12(2019)
Edland, R, Smith, N, Fredriksson, C, Normann, F, Fletcher, T.H, Andersson, K. - Evaluation of NOx-reduction measures in iron ore rotary kilns
Edland, R, Allgurén, T, Fry, A, Normann, F, Eddings, E - The relevance of homogeneous and heterogeneous reactions for NO formation in three PF-flame types
Reduced CO2 emissions from LKABs rotary kiln process – a study of the effect of alternative fuels
Swedish Energy Agency, 2013-05-01 -- 2016-04-30.
LKAB, 2013-05-01 -- 2016-04-30.
Chemical Process Engineering
Areas of Advance
Chalmers Power Central
Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 4606
Chalmers University of Technology
Kollektorn, MC2-huset, Kemivägen 9
Opponent: Prof. Peter Glarborg, Department of Chemical and Biochemical Engineering, Technical University of Denmark, Denmark