Study On Corrosion Characteristics Of Mixed Amine Solution Basing On MDEA

With the increasing demand of natural gas,amine deacidification technology is widely used in natural gas pretreatment process.Amine liquid formulation optimization and performance research is more and more important.During the actual production process,the corrosion of tower and equipment may cause shutdown and major safety accidents.The impurities produced by corrosion will also cause problems such as degradation effect and foaming.At present,the research on the corrosivity of amine solution at home and abroad has less research on the compound amine solution containing additives.In this paper,the corrosion characteristics of MDEA mixed amine solution are explored,aiming at more comprehensive study of the corrosion characteristics of different amine solutions,which is of guiding significance for the screening of factory amine solution.In this paper,the corrosion characteristics and corrosion control factors of tower material Q345 R low alloy steel in MDEA+DEA,MDEA+MEA and MDEA+PZ three kinds of complex amine solutions were studied by anodic polarization curve method and hanging weight loss method.The research shows that the corrosion regularity of Q345 R in the amine solution with two kinds of poor and rich conditions is different.For the poor amine solution,the corrosion control factor is OH-concentration.With the increase of the total amine concentration,mixing the lean amine most corrosive total amine concentration of DEA,MEA,PZ three kinds of additives respectively 40%,35%,35%;with the increase of additive concentration,corrosion resistance showed first increased and then decreased trend;the additive concentration was low,the same ratio of PZ MEA,compound amine corrosion is higher than that of DEA,and the additive concentration is high,DEA mixed amine corrosion resistance higher than the first two.For the amine rich solution,the corrosion control factor is the conductivity and the OH-concentration.With the increase of total amine concentration,the corrosion of mixed amine solution is weakened.With the increase of additive concentration,the corrosion of mixed amine solution is weakened.The corresponding additives of the three compound amine mixtures of the same ratio are strong to weak PZ,> MEA > DEA.According to this,it is important to enrich the performance evaluation index of amine solution from the angle of amine liquid corrosion,which is of great significance to the optimization of the ratio of amine liquid.