can someone tell me, how to estimate corrosion rate from process sampling and operating variables in refinery equipment?
Gas absorber and Amine regenerator in amine unit and reactor vessel in Hydrotreating unit?
Sampling and operating data are variables. To process the variables into an output, corrosion rate, you will need a model. The model could be a simple equation, or a complex software package. Otherwise, you can try scanning the literature to see whether others have reported any corrosion rates under process conditions that approximate to your observations.
For the hydrotreating unit the main issue is propably High Temp H2/H2S Corrosion.
There is a lot of reference to this on the web.
Modified Couper-Gorman curves will give you a relation between H2S content, temperature and expected corrosion rate for specific materials.