YOU’RE FIRED!

A LESSON FROM THE TRUMPS!

Nguyen Ngoc Bich

P. Eng.

Pangea Solutions Inc.

 

 

 

The non-intrusive corrosion monitoring devices can be classified into two main groups:

 

1.  Group A: monitoring the effects of the anodic reactions on wall thickness:

 

Fe à Fe2+ + 2e-                           (Reaction 1)

The dissolution of metal into the corroding environment results in a decreasing wall thickness which can be measured with a fiber optic sensor (for example, Fox-Tek Fiber Optic sensor), an electrical resistance matrix or ERM (for example, CorrOcean’s FSM-IT), UT, etc. This reaction determines the integrity of the structure to contain pressure.

 

2.  Group B: monitoring the cathodic reaction (hydrogen generation)

 

H2S + e- à HS- + H                   (Reaction 2a for sour gas)

2H à H2 (gas bubbles)           (Reaction 2b)

H à H diffusion                            (Reaction 2c)

 

The cathodic reaction rate (Reaction 2a) must be equal to the anodic reaction (Reaction 1) to maintain charge neutrality. In sour gas, the majority of generated Hydrogen will combine to form hydrogen gas bubbles inside the pipeline (Reaction 2b) but a fraction F of the generated Hydrogen atoms in Reaction 2a can diffuse through the steel to the outside wall to be measured by an electrochemical cell or be contained in a cavity which can read by a pressure gage (Beta foil).

 

Information about corrosion activity (Anodic reaction) can be obtained from Group B monitoring device (Cathodic reaction) if one understands the complex nature of Reaction 2c. More than often, the fraction F of the uncombined Hydrogen atoms is not precisely known. However, if the system behavior is known, one can have an idea of the corrosion trend.

 

One can relate the hydrogen monitoring in corrosion to a married couple’s state of happiness. One can watch the behavior of the wife and have some ideas on the husband’s activities. But the rules might not be the same for different couples. When my wife is shopping at Sears, I still have a job! When my wife is happy, I am happy! But for the Trumps, the rules were different! When Ivana Trump shopped at Marcus Neiman, she suspected that Donald was flirting with Marla Maples! When Ivana was finally happy, Donald was nearly bankrupted! As she did not get mad, she got everything from the divorce settlement!

 

Nguyen Ngoc Bich

Group 1