Removal of metallic iron on oxide slags

George N. Shannon, R. J. Fruehan, Seetharaman Sridhar

Research output: Contribution to journalArticlepeer-review

3 Scopus citations


It is possible, in some cases, for ground coal particles to react with gasifier gas during combustion, allowing the ash material in the coal to form phases besides the expected slag phase. One of these phases is metallic iron, because some gasifiers are designed to operate under a reducing atmosphere ( prm O2 of approximately 10-4 atm). Metallic iron can become entrained in the gas stream and deposit on, and foul, downstream equipment. To improve the understanding of the reaction between different metallic iron particles and gas, which eventually oxidizes them, and the slag that the resulting oxide dissolves in, the kinetics of iron reaction on slag were predicted using gas-phase mass-transfer limitations for the reaction and were compared with diffusion in the slag; the reaction itself was observed under confocal scanning laser microscopy. The expected rates for iron droplet removal are provided based on the size and effective partial pressure of oxygen, and it is found that decarburization occurs before iron reaction, leading to an extra 30- to 100-second delay for carbon-saturated particles vs pure iron particles. A pure metallic iron particle of 0.5 mg should be removed in about 220 seconds at 1400 °C and in 160 seconds at 1600 °C.

Original languageEnglish (US)
Pages (from-to)727-737
Number of pages11
JournalMetallurgical and Materials Transactions B: Process Metallurgy and Materials Processing Science
Issue number5
StatePublished - Oct 2009
Externally publishedYes

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Mechanics of Materials
  • Metals and Alloys
  • Materials Chemistry


Dive into the research topics of 'Removal of metallic iron on oxide slags'. Together they form a unique fingerprint.

Cite this