Corrosion Rate Measurement in Scrubber Unit

[hdamyan]

Hello all,

I am concerning with a iron/stell plant scrubber unit. I am curious about some situations. I need help and some answers to questions as you can see below.

1.What is the procedure of measurement of corrosion rate in Scrubber Units?
2.Is it necessary to measure corrosion rate in scrubbers?
3.If it is necessary to measure corrosion rate in scrubber what is the ASTM or NACE standart includes this measurement ?
You can see the pictures of the plant.
I'll apreciate any help.

Thanks.

 

[unclesyd]

I Would do a Ultrasonic Thickness,UT, survey to get a baseline. The use of corrosion date probes, unknown type, is indicative that someone suspected that corrosion might occur.
Can you comeback with more information such as:
Process materials.

Material of construction of the scrubber.

Type of probe used, like coupon or other, or any other indication of corrosion.

Has the scrubber ever been surveyed?

 

[strider6]

hdamyan

if u need to assess a corrosion rate you should fisrt of all define the expected corrosion mechanisms that are likely to take places in the scrubber. this will also give you an indication of where, and how much NDT you need. the same thing is for the corrosion monitoring systems, you need to use and place the correct type of probe in the most likely position where corrosion is expected.
this API standard can help u:
API RP 571 Damage Mechanisms Affecting Fixed Equipment in the Refining Industry
also
API 581.

hope this can help u

S.

Corrosion & Rust Prevention Control

 

[ErnieWise]

Hi Hdamyan

In our line of work we generally encounter pitting corrosion in heat affected weld zones (inside scrubber absorbers)rather than general corrosion.

Depending on the environment inside the scrubber and the alloy used, it can be very severe (but can be prevented).

Normally in line with installing a electrochemical corrosion prevention system we install a number of coupons that are designed to simulate pit conditions and this gives us a good indication about whether pitting rather than general corrosion is occurring.

http://www.corrosionservice.co.uk