Effect of Salt Content on The Corrosion Rate of Steel Pipe in Turbulently Flowing Solutions

Abstract

The effect of salt content on the corrosionrate of carbon steel pipe in aerated waterunder isothermal turbulent flow conditions(Reynolds number= 15000-110000 andtemperature of 30-60oC) is investigated byweight loss method. The test solutions weredistilled water (one time distilled) and seawater (0.5N NaCl). Also the results of 0.1NNaCl solution obtained by Hasan [2003]were considered. The effect of Reynoldsnumber temperature on the corrosion rateis also studied and discussed. For each run,nine specimens of carbon steel were placedin the test section and the corrosion rate foreach one was determined at every Re andtemperature and the average was taken.The variation of friction factor with Re andtemperature was determined by measuringpressure drop across the test section.The results revealed that the salt contenthas considerable effect on the corrosion ratefor the whole investigated range of Re andtemperature. The highest corrosion rate wasencountered in sea water (3.5% NaCl). Alsodistilled water causes considerable corrosionrate but it is lower than for the whole rangeof Re and temperature. Also it is found thatReynolds number increases the corrosionrate depending on temperature.Temperature affects the corrosion rate bychanging two main parameters, oxygensolubility and diffusivity.