Iron and steel mills

From Brazil to India to China, many iron and steel producers using classic blast furnace processes tell us they need to change their PCI lances every couple of weeks.

Pulverized coal injection lances (PCI)

Not only is changing PCI lances every other week a major cost and a problem due to the maintenance shutdown, but it also involves real safety risks. One producer even showed us a highly corroded lance fabricated with a standard grade that had completely disintegrated after just one week.

300% increase in lance lifetime

Price/performance analyses with our customers often show that better grade selection can significantly improve the lance lifetime. In one case, a
Brazilian steel mill increased the lifetime of its blast-furnace lances by 300 percent by switching from TP 310H to Alleima® 253 MA in pulverized coal
injection lances. Payback time was less than one year and they saw reductions in maintenance costs as well as a boost in pig-iron productivity.

Recuperators

Nothing should go to waste in a modern plant. The use of waste heat to preheat process gas is thus a natural way to save energy and drive down costs. Whether you’re in the glass, steel, iron, pig iron or another energy-intensive industry, recuperators are great fuel savers (see the diagram below). The challenge is that flue-gas corrosion can build up on the tubes, leading to material degradation, which drastically increases maintenance costs.

Preventing material degradation

To avoid this, we often recommend Alleima® 253 MA tube, which has excellent HT corrosion resistance properties – especially for the direct reduction of iron ore (DRI). Experience shows that the payback on investment can be as quick as one year when changing, for example, from an air preheat of 650°C using common ferritic or austenitic materials to an air preheat of 800°C using Alleima® 253 MA. For higher flue-gas temperatures in the 1,250°C range, such as in the glass industry, we recommend instead our Alleima® 4C54 grade, thanks to its resistance to sulfidating environments.