Corrosion resistance of a steel under an oxidizing atmosphere in a fluid catalytic cracking regenerator

Abstract

In the present work, the corrosion resistance of an ASTM A 387 G11 steel was evaluated under two conditions: an oxidizing atmosphere in a fluid catalytic cracking regenerator of a petroleum processing unit and a simulated atmosphere in the laboratory, at temperatures of 650 °C and 700 °C. The characterization of the phases present in the oxidized layer was carried out by X-ray diffraction (XRD), optical microscopy (OM) and scanning electron microscopy (SEM) with X-ray energy dispersive analysis (EDS). Severe corrosion was observed after exposure to both the real and simulated conditions, with formation of several iron oxides (Fe2O3, Fe3O4 and FeO) in the product scale layer, as well as a slight inner oxidation and sulfidation of chromium in the substrate. Internal nitridation of the silicon and the manganese was observed only in the real condition, probably related to the long-term exposure inside the regenerator

Evolution of TSA/TSZ coatings: a review on recent advances on cold gas spraying for steel corrosion protection

“…In this case, the corrosion products showed certain positive effects on coating corrosion resistance as they sealed or covered the coating porosity and did not allow the diffusion of the corrosive agents to the steel surface. Considering the high oxidation resistance shown by these Al coatings, the Rizzo group studied the opportunities of using TSA in a fluid catalytic cracking regenerator (very high oxidant atmosphere, O 2 = 2% and SO 2 = 3%) (Caminha et al 2004). Under these conditions, FS Al coating was not totally able to protect steel from oxidation at long exposure times, since some O 2 and SO 2 diffusion through the coating could not be avoided because of the high porosity showed by the Al coating.…”

Considerations for the incorporation of measured surfaces in finite element models

“…(2001) and Tang et al (2006). However, visual inspection of the surfaces presented by Glynn et al (2001) and Caminha et al (2004) reveals that surface layers may have variable thicknesses and that the interface may have substantially a different topography than the surface.…”