Atmospheric Corrosion in an Oil Refinery Located on a Tropical Island under New Pollutant Situation

Outdoor–indoor atmospheric corrosion of low carbon steel (LCS AISI-1020) was studied in an oil refinery. Three outdoor exposure sites and one indoor exposure site were placed. Corrosivity categories of the atmosphere were defined according to the procedures established on ISO 9223: 2012 and ISO-11844: 2006. There are three ways for classifying corrosivity categories: direct determination by weight loss, estimated classification based on environmental parameters, and estimation using dose response functions. High corrosivity category (C4) was determined by all three procedures for the outdoor exposure site close to the coast of Havana Bay. In the other two outdoor exposure sites (farther from the coast), the corrosivity category of the atmosphere estimated was high (C4), while corrosivity category determined was medium (C3). Sulfur compounds’ deposition rate was higher than chloride deposition in outdoor–indoor exposure conditions, as it is expected for an oil refinery. However, the most influential factor for atmospheric corrosion was chloride deposition; this means that in the composition of sulfur compounds, a significant amount of sulfur oxides is not present (very corrosive agents). It means the emissions of aggressive gases by the oil refinery is almost negligible; it is a new situation respecting pollution inside an oil refinery. Under indoor exposure conditions, corrosivity categories of the atmosphere estimated and determined was high (IC4). The factor most influential on atmospheric corrosion was the \(\mathrm{RH}-\mathrm{T}\) complex. Morphology of corrosion products was characterized. Lepidocrocite with different morphologies was the main corrosion product present.