Modeling Refractory Wear Due to Chemical Corrosion in Slagging Gasifiers

Entrained-flow gasification has proven to be an efficient technol. to convert solid fuel (coal, biomass, etc.) into energy-rich gaseous chems. However, there are several tech. issues that economically limit its broader application. One of them is refractory degrdn. For example, it costs millions of dollars and several days of shutdown to replace refractories in typical gasification-based installations. Due to the high-temp., high-pressure, and harsh operating conditions, it is difficult to online measure refractory wear. Models are needed to simulate the refractory degrdn., monitor the refractory remaining useful life, and control/improve the operational performance for the gasification process. In the present work, a dissoln. model has been developed based on a CaO-Al2O3-SiO2 slag. This model incorporates slag flow and heat transfer contributions and can be used to account for the refractory wear due to chem. corrosion. The effects of temp., compn., slag flow, and slag deposition rate are analyzed and discussed. Results indicate that temp. and slag compn. have significant effects on the corrosion rate. This model, combined with the spalling and coal gasification models, will be used to support the development of monitoring capabilities to online access the wear of refractory liners in entrained-flow gasifiers.