Corrosion characteristic of selected ferrous metal samples (plain and alloyed ductile iron, low carbon steel and austenitic stainless steel) in crude oil was investigated using weight loss method. The microstructures ...Corrosion characteristic of selected ferrous metal samples (plain and alloyed ductile iron, low carbon steel and austenitic stainless steel) in crude oil was investigated using weight loss method. The microstructures of the coupons were taken before and after corrosion test. It was observed that all the materials experience gain in weight within the first 10 days in the medium. This weight gain is attributed to the formation of hard and passive phases which acted as strong protective barriers to corrosion. It was also observed that the rate of corrosion decreased with increase in the number of days of exposure for all the coupons, this may be probably due to the deposition of corrosion products that tend to shield the corroding surface from further corrosion attack, there by depressing the rate of corrosion. This result shows that despite initial low corrosion resistance of plain ductile iron, it can still be considered, alongside other materials, for application in pipelines and storage facilities for crude oil.展开更多
The characterization of five different Nigerian clay deposits has been carried out by employing three different characterization techniques (X-ray Diffraction, X-ray Fluorescence and Scanning Electron Microscopy/EDX)....The characterization of five different Nigerian clay deposits has been carried out by employing three different characterization techniques (X-ray Diffraction, X-ray Fluorescence and Scanning Electron Microscopy/EDX). The clays obtained from the various deposits were carefully prepared for the analyses and the results obtained were compared to confirm the consistency and reliability of the different methods employed. The results revealed the various desirable (SiO2 and Al2O3) and deleterious (Fe3O4, K2O, MgO, MnO and Na2O) elements and compounds contained in the clay samples in the various proportions and the appropriate purification technique required for preparing the clays for high temperature applications. Consequent upon the identification of the deleterious impurities, oxalic acid at different concentrations was used to leach the impurities out of the various clays. However, three out of the five deposits were chosen for purification because they possess the least quantities of the most deleterious (Fe2O3) of the impurities.展开更多
文摘Corrosion characteristic of selected ferrous metal samples (plain and alloyed ductile iron, low carbon steel and austenitic stainless steel) in crude oil was investigated using weight loss method. The microstructures of the coupons were taken before and after corrosion test. It was observed that all the materials experience gain in weight within the first 10 days in the medium. This weight gain is attributed to the formation of hard and passive phases which acted as strong protective barriers to corrosion. It was also observed that the rate of corrosion decreased with increase in the number of days of exposure for all the coupons, this may be probably due to the deposition of corrosion products that tend to shield the corroding surface from further corrosion attack, there by depressing the rate of corrosion. This result shows that despite initial low corrosion resistance of plain ductile iron, it can still be considered, alongside other materials, for application in pipelines and storage facilities for crude oil.
文摘The characterization of five different Nigerian clay deposits has been carried out by employing three different characterization techniques (X-ray Diffraction, X-ray Fluorescence and Scanning Electron Microscopy/EDX). The clays obtained from the various deposits were carefully prepared for the analyses and the results obtained were compared to confirm the consistency and reliability of the different methods employed. The results revealed the various desirable (SiO2 and Al2O3) and deleterious (Fe3O4, K2O, MgO, MnO and Na2O) elements and compounds contained in the clay samples in the various proportions and the appropriate purification technique required for preparing the clays for high temperature applications. Consequent upon the identification of the deleterious impurities, oxalic acid at different concentrations was used to leach the impurities out of the various clays. However, three out of the five deposits were chosen for purification because they possess the least quantities of the most deleterious (Fe2O3) of the impurities.