This work provides a computational model that will help to predict the life-span of SiC based refractories used in waste to energy plant (WTE) linings. For this particular application, gas present in the atmosphere diffuse through the porosity and react with the refractory producing SiO2 and CaSiO3 solids. These new phases clog gradually the pores and cause swelling of the material and as a result irreversible deformation of the lining. The proposed thermo-chemo-mechanical model that simulates these phenomena is briefly summarized and some of the parameters are identified. Then, first results obtained with the model implemented in a F.E.M code are shown. They prove the ability of the model to reproduce qualitatively the swelling of post-mortem bricks taken from WTE linings.