The adverse impact of particle adhesions and agglomerations on gas flow performance is a prominent concern in high volume extraction systems. The formation of severe skull deposits, involving agglomeration and adhesion processes, particularly at elevated operation temperatures, necessitates laborintensive and costly manual removal. Consequently, investigating conditions that promote increased skull generation and exploring mechanisms for spontaneous removal through crack formation and chipping are of great significance. This study comprehensively documents the operational conditions of an industrial extraction system, accom panied by elemental gas phase composition analyses. Additionally, the chemical compositions of agglomerated adhesion samples were assessed using X-ray diffraction (XRD) and inductively coupled plasma optical emission spectroscopy (ICPOES), and their inner structure was examined through SEM. Subsequently, mechanisms leading to these build-ups were simulated on laboratory scale by covering original wall surface samples with agglomeration powder screened for a defined particle size. In experiments conducted at various high temperatures ranging from 800 °C to 1200 °C, while varying the CaCO3 content levels in the powders, a layered structure similar to the real system was successfully acquired. Moreover, under certain defined conditions and different atmospheres, crack formation, significantly impacting the chipping behavior of the skull formations from wall surfaces during application, was observed and the compressive strength was examined. Through our laboratory experiments, specific operating conditions within the calcination cycle were revealed, leading to a substantial enhancement of autonomous discharge of large particle–wall agglomerations. Based on these findings, we propose general process optimization steps to improve the overall performance of the extraction system, such as reduction of fine CaCO3 particles and reduction of the gas flow temperature.
1. Henry, C. Surface forces and their application to particle deposition and resuspension. In Particles in Wall-bounded Turbulent Flows: Deposition, Re-suspension and Agglomeration (Minier, J.-P. and Pozorski, J., eds). Springer, Cham, 2017, 209–261.
https://doi.org/10.1007/978-3-319-41567-3_5
2. Minier, J.-P. A general introduction to particle deposition. In Particles in Wall-bounded Turbulent Flows: Deposition, Re-suspension and Agglomeration(Minier, J. P. and Pozorski, J., eds). Springer, Cham, 2017, 1–36.
https://doi.org/10.1007/978-3-319-41567-3
3. Widder, L., Adam, K., Egger, M. and Varga, M. Mechanisms and prevention of skull formation in high temperature gas extraction system. AIP Conf. Proc., 2024, 2898(1), 030001.
https://doi.org/10.1063/5.0189466
4. Henry, C. and Minier, J.-P. Progress in particle resuspension from rough surfaces by turbulent flows. Prog. Energy Combust. Sci., 2014, 45, 1–53.
https://doi.org/10.1016/j.pecs.2014.06.001
5. Wang, X., You, C., Liu, R. and Yang, R. Particle deposition on the wall driven by turbulence, thermophoresis and particle agglomeration in channel flow. Proc. Combust. Inst., 2011, 33(2), 2821–2828.
https://doi.org/10.1016/j.proci.2010.08.009
6. Khalifa, A. and Breuer, M. An efficient model for the breakage of agglomerates by wall impact applied to Euler–Lagrange LES predictions. Int. J. Multiph. Flow., 2021, 142, 103625.
https://doi.org/10.1016/j.ijmultiphaseflow.2021.103625
7. Giffin, A. and Mehrani, P. Effect of gas relative humidity on reactor wall fouling generated due to bed electrification in gas-solid fluidized beds. Powder Technol., 2013, 235, 368–375.
https://doi.org/10.1016/j.powtec.2012.10.037
8. Jones, R., Pollock, H. M., Geldart, D. and Verlinden, A. Inter-particle forces in cohesive powders studied by AFM: effects of relative humidity, particle size and wall adhesion. Powder Technol., 2003, 132(2–3), 196–210.
https://doi.org/10.1016/S0032-5910(03)00072-X
9. Shotton, E. and Harb, N. The effect of humidity and temperature on the cohesion of powders. J. Pharm. Pharmacol., 1966, 18(3), 175–178.
https://doi.org/10.1111/j.2042-7158.1966.tb07844.x
10. Varga, M., Rojacz, H., Widder, L. and Antonov, M. High temperature erosion-corrosion of wear protection materials. J. Bio- Tribo-Corros., 2021, 7(3), 87.
https://doi.org/10.1007/s40735-021-00504-9
11. Longbottom, R. J., Monaghan, B. J., Pinson, D. J. and Chew, S. J. Understanding the self-sintering process of BOS filter cake for improving its recyclability. J. Sustain. Metall., 2019, 5, 429–441.
https://doi.org/10.1007/s40831-019-00233-x
12. Peng, B., Chai, L.-Y., Song, H.-C., Peng, J., Min, X.-B., Wang, Y.-Y. et al. Study on stainless steelmaking dust agglomeration. J. Cent. South Univ. Technol., 2004, 11, 45–50.
https://doi.org/10.1007/s11771-004-0010-9
13. Krztoń, H. J. 2010. Quantitative phase composition of steelmaking dust from polish steel industry. Solid State Phenom., 2010, 163, 31–37.
https://doi.org/10.4028/www.scientific.net/SSP.163.31
14. Vereš, J., Šepelák, V. and Hredzák, S. Chemical, mineralogical and morphological characterisation of basic oxygen furnace dust. Miner. Process. Extr. Metall., 2015, 124(1), 1–8.
https://doi.org/10.1179/1743285514Y.0000000069
15. Li, Z., Zhu, R., Ma, G. and Wang, X. Laboratory investigation into reduction the production of dust in basic oxygen steelmaking. Ironmak. Steelmak., 2017, 44(8), 601–608.
https://doi.org/10.1080/03019233.2016.1223906
16. Delhaes, C., Hauck, A. and Neuschütz, D. Mechanisms of dust generation in a stainless steelmaking converter. Steel Res., 1993, 64, 22–27.
https://doi.org/10.1002/srin.199300977
17. Steer, J., Grainger, C., Griffiths, A., Griffiths, M., Heinrich, T. and Hopkins, A. Characterisation of BOS steelmaking dust and techniques for reducing zinc contamination. Ironmak. Steelmak., 2014, 41(1), 61–66.
https://doi.org/10.1179/1743281213Y.0000000106
18. Yi, C., Zhu, R., Chen, B.-Y., Wang, C.-R. and Ke, J.-X. Experimental research on reducing the dust of BOF in CO2 and O2 mixed blowing steelmaking process. ISIJ Int., 2009, 49(11), 1694–1699.
https://doi.org/10.2355/isijinternational.49.1694
19. Russell, A., Schmelzer, J., Müller, P., Krüger, M. and Tomas, J. Mechanical properties and failure probability of compact agglomerates. Powder Technol., 2015, 286, 546–556.
https://doi.org/10.1016/j.powtec.2015.08.045
20. Van der Zwan, J. and Siskens, C. A. M. The compaction and mechanical properties of agglomerated materials. Powder Technol., 1982, 33(1), 43–54.
https://doi.org/10.1016/0032-5910(82)85037-7
21. Meissner, H. P., Michaels, A. S. and Kaiser, R. Crushing strength of zinc oxide agglomerates. Ind. Eng. Chem. Process Des. Dev., 1964, 3(3), 202–205.
https://doi.org/10.1021/i260011a003
22. Bika, D. G., Gentzler, M. and Michaels, J. N. Mechanical properties of agglomerates. Powder Technol., 2001, 117(1–2), 98–112.
https://doi.org/10.1016/S0032-5910(01)00318-7
23. Priss, J., Klevtsov, I. and Winkelmann, H. High-temperature chlorine corrosion in presence of sulfur containing and potassium external deposits. In Proceedings of the 23rd International DAAAM Symposium, Zadar, Croatia, 21–28 October 2012. DAAAM International, Vienna, Austria, 2012, 0911–0916.
https://doi.org/10.2507/23rd.daaam.proceedings.211
