Analysis of Chemical Corrosion Mechanism of Oil and Gas Pipelines and Its Protective Measures
The corrosion behavior of epoxy resin,polyurethane,zinc-based coatings,and new composite coatings in simulated salt water,acidic and alkaline environments was evaluated by using analytical methods such as electrochemical impedance spectroscopy,salt spray experiments,and temperature cycles.Experimental results showed that in acidic environments,the corrosion rate of pipeline materials was the highest,reaching 0.60 mm·a-1,while in alkaline environments,the corrosion rate was the lowest,only 0.20 mm·a-1.In addition,impedance analysis revealed that the impedance value in the acidic environment dropped from the initial 1510 Ω·cm-2 to 312 Ω·cm-2,reflecting that the corrosive medium damaged the protective layer very quickly and severely.New composite coatings and cathodic protection systems could significantly improve corrosion protection effectiveness.The cathodic protection system reduced the corrosion rate to 0.06 mm·a-1,showing better protective effect than sacrificial anode protection(corrosion rate of 0.14 mm·a-1).Field data showed that pipelines using new anti-corrosion technology significantly reduced corrosion rates in actual applications.After 4 years of operation,the corrosion rate of facilities using the new technology only increased to 0.6 mm·a-1,while the corrosion rate of facilities with traditional anti-corrosion measures increased to 2.0 mm·a-1.
Oil and gas pipelinesCorrosion mechanismElectrochemistryComposite materialsCorrosionReactionProtective measures
NETL
NSTL
万方数据
