| Abstract [eng] |
Corrosion as a natural phenomenon is the material destructive chemical and electrochemical reaction with its surrounding environment. Corrosion is an unavoidable problem in petroleum oil refinery industries due to the complicated work conditions such as high temperature, high pressure, pH value and ion concentrations in aggressive media. As the main construction material for equipment in oil, gas and petroleum industries is steel due to his availability, and low cost. Steel is affected by corrosion. In the present research, analyses were made on the carbon steel used in the condensate treatment block (CTB) at SC \"ORLEN Lietuva\" and on an effect on the equipment of aggressive media in the absence and the presence of the inhibitors. To quantify corrosion rate a weigh loss method and linear polarization resistance technique (LPR) were used. The experimental results have shown that the technological condensate (sour water) from CTB is more corrosive media than the salt water from desalination unit or mixed water stream which will feed CTB after reconstruction. Inhibitor CHIMEC 1839 slowed down the corrosion process in the salt water media more than three times and in the mixed water stream more than twice. To increase the corrosion resistance of steel was chosen thermal-chemical surface hardening -nitriding and carburizing -hardening. The experimental results from weigh loss method and linear polarization resistance technique have shown that corrosion resistance provided by carburizing –hardening is better than that provided by nitriding. |
