Küttner GmbH & Co. KG (Essen, Germany):

Schott R., Dr. Eng., Head of Processing Equipment and Technological Development, r.shott@kuettner.com

The blast furnace process is the most important process to produce crude iron. The necessary process energy is mainly covered by coke. A decisive measure in improving cost effectiveness by reducing the blast furnace coke rate was the injection of auxiliary fuels like pulverized coal, oil or natural gas into the raceway of the blast furnace. This paper will focus primarily on five important steps of continuous improvements in pulverized coal injection technology including the reduction of transport and injection gas to a minimum, the development of PCI-plant design, the implementation of a fast and accurate injection rate control system, long-distance dense phase conveying and the Oxycoal⁺ technology. Optimal gasification of injected pulverized coal in the blast furnace is discussed and conveying of dense phase and dilute phase is compared. The number of blast furnaces in the world equipped with diff erent auxiliary fuel injection systems and efficiency enhancement of reductants use in the blast furnace using pulverized coal injection are observed. Influence of Oxycoal⁺ technology on coal gasification within the tuyere and the raceway of the blast furnace is estimated. Finally future trends concerning pulverized coal injection into the blast furnace are discussed.

1. Plantfacts-Datenbank, Ausgabe 2009, Stahlinstitut VDEh, Düsseldorf.
2. Schott, R.; Schott, H.-K.; Malek, C.: Effizienzsteigerung des Hochofenbetriebs durch den Einsatz der Küttner-Oxycoal-Technik, Jubiläumssitzung des VDI-GVC Fach ausschusses „Hochtemperaturtechnik“, Düsseldorf, Februar 2008.
3. Peters, M.; Korthas, B.; Schmöle, P.: The past, present and future of pulverized coal injection at ThyssenKrupp Steel AG, Proc. 36^th McMaster University Symp. on Iron and Steelmaking, 23.–25. Sept. 2008, Hamilton, Canada, S. 14/29.
4. Schott, R.; Malek, C.; Schott, H.-K.: Chemie Ing. Tech. 84 (2012) Nr. 7, S. 1076/84.
5. Schmöle, P.; Peters, M.: Injection of auxiliary reducing agents into the blast furnace — Effects on metallurgy and costs, Intern. STE Technologies Symposium, Kaohsiung, Taiwan, 3.-5. Nov. 2008.
6. http://www.co2-handel.de/

7. Gertz, J.: The new unloading, drying, grinding and injection equipment for blast furnaces at Hüttenwerke Krupp Mannesmann GmbH in Duisburg, Germany, IAS 8^th Ironmaking Conf., Rosario, Santa Fe, Argentinien, 1.– 3. Nov. 2011.

8. Joksch, M.: Thermische Vorgänge beim Einblasen von Kohle in den Hochofen — Strömungs- und verfahrenstechnische Optimierung von Einblaslanzen, RWTH Aachen, 1993 (Diss.). 

9. Liang, N.-W.; Chang, C.-T.: Practice of promoting pulverized coal injection rate at blast furnace No. 4 of China Steel Corp., Proc. 36^th McMaster University Sympos. on Iron and Steelmaking, 23.–25. Sept. 2008, Hamilton, Canada, S. 47/61.
10. Lüngen, H. B.; Schmöle, P.: stahl u. eisen 124 (2004) Nr. 11, S. 63/72.
11. Danloy, G.; Berthelement, A.; Grant, M.; Borlee, J.; Sert, D.; van der Stel, J.; Jak, H.; Dimastromatteo, V.; Hallin, M.; Eklund, N.; Sundqvist, L.; Sköld, B.-E.; Lin, R.; Feiterna, A.; Korthas, B.; Müller, F.; Feilmayr, C.; Habermann, A.: ULCOS — pilot testing of low CO₂ blast furnace process at the experimental BF in Lulea, Rev. de Met. 106 (2009) Nr. 1, S. 1/8.
12. Babich, A.; Gudenau, H. W., Formoso, A.; Mav rommatis, K.; Froehling, G.; Garcia, L.: Choice of technological regimes of a blast furnace operation with injection of hot reducing gases, Revista de la Metalurgia 38 (2002) Nr. 4, S. 288/305.
13. Helle, H.; Helle, M.; Saxen, H.; Pettersson, F.: ISIJ Intern. 49 (2009) Nr. 9, S. 1316/24.
14. Petela, R.; Hutny, W.; Price, J. T.: Adv. Environm. Res. (2002) Nr. 6, S. 157/70.