Session: OAC-06-01 Operation and Maintenance of Pressure Vessels, Heat Exchangers, Piping and Supports

Paper Number: 61869

Start Time: Wednesday, July 14, 2021, 09:00 AM

61869 - Development of Inhibitor for Corrosion Protection of Condensate Stripping Process in Industrial Coal Gasification Unit 

The condensate involving HS^-、CO₃^-、Cl^- and NH₄⁺ usually causes severe corrosion of typical 20 carbon steel in condensate stripping process of industrial coal gasification unit. The corrosion can easily lead to failure of pipe fittings and vessels, and result in economic losses and personal injury. To protect industrial coal gasification unit against corrosion, five inhibitors including imidazoline, imidazoline amide, mannich base quaternary fammonium salt, pyridine, and sodium molybdate are investigated with experiment of linear polarization curve, polarization curve, electrochemical impedance spectroscopy (EIS). The gas-liquid two phase experimental conditions mixed with suitable concentration of H₂S、CO₂ and NH₄Cl are as close to the industrial alkalescent corrosion environment as possible. The experiment results indicate that two inhibitors of the mannich base quaternary ammonium salt and the pyridine have better effects on corrosion protection than others at the same injection concentration of 100ppm, and their inhibition efficiency even reach to 90.72% and 90.65%, respectively. A new compound inhibitor is developed based on the mannich base quaternary ammonium salt and the pyridine in terms of above results. The new compound inhibitor’s efficiency further reaches to 95.5%, suggesting that the new compound inhibition has better effect on corrosion protection than either of two single inhibitors above.

Presenting Author: Meng He China Special Equipment Inspection and Research Institute

Authors:

Meng He China Special Equipment Inspection and Research Institute
Haoyuan Kang China Special Equipment Inspection and Research Institute
Juanbo Liu China Special Equipment Inspection and Research Institute
Sheng Chen China Special Equipment Inspection and Research Institute
Xueru Gong China Special Equipment Inspection and Research Institute
Li Sun China Special Equipment Inspection and Research Institute