How to address the corrosion of the inner wall of the overhead oil water separator in petrochemical atmospheric and vacuum distillation units?
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The image below shows the degasifier water separator used in petroleum chemical atmospheric and vacuum distillation units; the operating conditions are: medium, light oil, water； Temperature, 50 degrees ； Pressure: 0.5 MPa, material is carbon steel. Due to corrosion by the H2S-HCl-H2O system, the inner wall of the tank suffered severe corrosion after being in use for over a year, with a large amount of rust forming. It is to ask how to address the issue of corrosion on the inner wall of the tank under such operating conditions.
The following methods can be used to address the issue of corrosion on the inner wall of the water separation tank: 1. **Material upgrade**: Consider replacing the current material with ones that have better corrosion resistance, such as stainless steel or alloy steel, in order to improve resistance to chemical agents. 2. **Corrosion-resistant coating**: A corrosion-resistant coating, such as an epoxy resin coating, is applied to the inner wall of the tank to enhance its resistance to corrosion. Ensure that the coating has good chemical stability and adhesion. 3. **Cathodic protection**: An electrochemical method is used, involving the installation of sacrificial anodes inside the tank or the application of an external current, in order to suppress the corrosion process through cathodic protection. 4. **Operation parameter optimization**: Monitor and control the pH level and the concentrations of other chemicals in the tank, and adjust operating conditions to reduce corrosivity. 5. **Regular inspection and maintenance**: Increase the frequency of inspections of the tank, regularly clean out deposits and rust inside it, and identify and address corrosion issues promptly. It is recommended to conduct a detailed corrosion assessment of the tank before selecting the most appropriate protective measures. If conditions permit, the combined use of multiple protection strategies will be more effective in providing long-term protection for equipment. .