The Development of Puverized Coal Injection Lance With Air Cooling in N0.3 Blast Furnace

摘要

Except reducing fuel cost, PCR can demonstrate the BF technical level due to requiring more delicate skills for promoting PCI operation. Since the commencement of PCI at No. 3 BF in November, 1993, the difficulties encountered during increasing PCI rate to 130 kg/thm were lance clogging and erosion, tuyere failures, and the poor permeability in furnace. The stability of PC transportation has been improved by the PCI lance clogging prevention system, the selection of proper PC specification, the transportation line modification as reducing pressure drop, and the double air-cooled coaxial lance, etc. The PC combustion efficiency has also been enhanced by double air-cooled coaxial lance as decreasing unburnt coal Through the proper burden distribution, the adjustment of theoretical flame temperature and the reduction of slag rate, the PCI rate has reached at 160 kg/thm along with higher productivity. The total benefit of this project is estimated to be 131 million per year due to the reduction of the fuel cost at No. 3 BF of CSC. Besides, the greenhouse effect is reduced with less carbon dioxide emissioa