CORROSIVITY OF ANHYDROUS ETHANOL, HYDRATED ETHANOL(1) AND FUEL E25(2) (25 ETHANOL/75 GASOLINE)

摘要

The objective of the work was to study the corrosion of API 5LX 46 and API 5LX 65 alloys,rnused for pipelines, in anhydrous ethanol, hydrated ethanol and fuel E25 through laboratoryrnimmersion tests, NACE TM-0172 tests and dynamic tests (corrosion loops). Based on thernresults of this study, it was concluded that it is advisable that the internal surface ofrnhydrated ethanol storage tanks be painted in order to avoid the corrosion of the internalrnwalls which, despite being incipient, determines color changes which is unacceptable in thernmarket. Furthermore, in pipelines used only for ethanol transportation, the painting of therninternal walls of the tubes is not necessary because both the anhydrous ethanol and thernhydrated ethanol are not aggressive to the steel, as long as the relative movement of thernliquid is guaranteed. Finally, in pipelines used for ethanol and for petroleum derivativesrntransportation, it is advisable that the internal surfaces of these pipes be painted in order tornavoid the contamination of the ethanol (anhydrous or hydrated) which makes the ethanolrnaggressive to the steel and changes its color (unacceptable in the market).