Carbonate Coatings as Protective Barriers for Pipe Borne Water Transport Material

Lasisi Ejibunu Umoru, Abimbola Oladipo, Oladeji Oluremi Ige

Department of Materials Science and Engineering, Obafemi Awolowo University, Ile-Ife,Nigeria.

DOI: 10.4236/jmmce.2012.116044                

Abstract

This paper presents the report of corrosion prevention study carried out on plain carbon steel lined with calcite, magnesium carbonate and dolomite as coats. Eight samples each of the steel were dipped into solutions of CaCO₃, CaCO₃ and MgCO₃, and MgCO₃. Pipe borne water obtained from Obafemi Awolowo University, Ile-Ife water works was used as the environment. The corroded sample surfaces were subject to microstructural characterization using optical microscopy technique. The results obtained showed that the steel exhibited minimum corrosion rate of less than 0.5 mm/yr in dolomite, followed by MgCO₃ and then by CaCO₃ with corrosion rate far above 0.5 mm/yr bench mark. The unlined (control) samples have maximum corrosion rate of 0.8 mm/yr. the microstructures revealed widespread localized attacks and to a uniform corrosion. The dolomite lined samples are recommended for corrosion prevention of plain carbon steel in pipe borne water.

Keywords

Plain carbon steel, Calcite, MgCO₃, Dolomite and Microstructure

Conflicts of Interest

The authors declare no conflicts of interest.

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