corrosion in tube bundle 2

[alfonzob74]

Hi everyone!
We have a carbon steel heat exchanger TEMA type AES. The cooling water flows through the shell side and the hot 1-butene enters the tube side. The tube-bundle is quite corroded and it has 2 years of service. The heat exchanger is taken out of service on a monthly basis in order to remove the tube side of fouling caused by polybutadiene. The head floating is removed and the water is drained leaving the wet surface and exposed to the atmosphere. The mechanical cleaning takes about 3 days. After this, the heat exchanger is put back on service. Cooling water is treated with corrosion and scale inhibitors. We assumed that the corrosion is caused by the exposure of the wet tube-bundle to the environment. Can anyone help me how can I mitigate the corrosion? Thanks in advance.

 

[metengr]

Not enough information related to extent of corrosion damage, location of corrosion damage, etc. First, you need to confirm the corrosion damage mechanism and don't assume anything. Remove a tube sample for metallurgical analysis. Second, you need to map the locations of damage for a proper condition assessment. Me thinks with only 2 years of service, you have something more serious than wet tube atmospheric corrosion.

 

[EdStainless]

Mapping damage and getting a professional analysis done are where you need to start.

I suspect that the fouling and perhaps some trace chemical in water are behind this.
You may even have some MIC issues.
You need to seriously look at a redesign (configuration and materials) if you can only run 1 month between manual cleanings.
You might also look at the cleaning method, you may be doing damage there.
At the very least you need to find a way to remove the polybutadiene from the cooling water. These outages are costing you a fortune.

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Plymouth Tube

 

[alfonzob74]

Hi mate! Thanks for your answers.
Pertinent images attached here:

[url=https://www.asuswebstorage.com/navigate/s/FCF000787D9046259CB0DDD7AB0DE58DY]

The tube bundle was removed. In addition, cooling water flows to <0.3m/s ( <1ft/s), TSS>10ppm and conductivity >1000us/cm. I think it has caused high fouling risk and corrosion under deposit.