The Corrosion of High Chrome Oxide Refractory Liners in Slagging Gasifiers by Carbon Feedstock Impurities

Gasifiers are high temperature, high pressure containment vessels used to convert carbon feedstock, such as coal or petcoke, into H₂ and CO, called syngas.  The syngas produced by gasification is used as a fuel in energy production or as a raw material feedstock for chemical synthesis.  Slagging gasifiers used in gasification operate at temperature between 1325-1575^oC and pressures between 300-1000 psi; and are lined with high chrome oxide refractory materials.  Impurities exist in the carbon feedstock, which include Si, Fe, Ca, Al, Na, and S in coal; and include additional elements of Ni and V in petcoke.  Depending on the feedstock source, the quantities of impurities generally range from one to over ten pct; leading to ash waste quantities reaching 100 tons/day or higher.  At the operational temperatures of a slagging gasifier, the ash wastes liquefy and react with or penetrate within the refractory liner pores; leading to their wear and corrosion, and ultimately, premature brick failure.  This paper will discuss interactions between slag components and the refractory liner that lead to lining failure.