Loesche GmbH, Düsseldorf:

T. Korz, Eng., Sales Manager, tobias.korz@loesche.de

H. Wulfert, Dr.Eng., Consultant in the field of Production Technology

In the wake of ever increasing environmental awareness in government and the general public, the reuse of residue and by-products is a highly current subject in which the CO₂ challenge and conservation of resources play central roles. For years, efforts to use oil-containing mill scale as a material productively most often failed due to the considerable costs of the developed or envisaged processes. The patented technology developed by Loesche in 2003 was quickly welcomed by the industry and is currently being successfully used in ironwork PCI systems. Coal mill type LM 21.2 D at a German blast furnace is shown. The process scheme for preparing the mixture of coal and oil containing mill scale is analyzed. Degrees of conversion of different types of coal and mixtures of coal with mill scale and additives as a function of the oxygen/carbon ratio is observed. Ash and mill scale content of the pulverized coal/mill scale mixture during the first operation test on blast furnace A and injection rate respectively mass flow of coal line No. 25 at blast furnace B (injection of pure coal without mill scale as well as injection of coal/mill scale mixture) are displayed. Grain size distribution of the pulverized coal/mill scale mixture is calculated and built on the diagram, as well as ash content of the different grain fractions.