Abstract
Slagging coal gasifiers suffer from significant attack by the coal slag on the refractory liner. To better understand the corrosive attack on the refractory the interactions were thermochemically simulated. The slag is observed to penetrate the refractory, which complicates modeling the phase behavior of the slag-penetrated interior of the refractory. To address this issue a simple strategy was adopted such that step-wise changes in composition with decreasing slag content were assumed to account for the compositional changes as slag penetrates the refractory, at least partially through its thickness. The thermochemical equilibrium calculations following this strategy typically yielded three solution phases as well as the stoichiometric crystalline phases AlPO4, Ca3(PO4)2, and (MgO)(Cr2O3), depending on composition/penetration. In addition, under some conditions a slag liquid miscibility gap exists such that two slag liquids co-exist.