Cleaning Shell Side of Exchanger

[advsign]

Hello Guys,
Quick question to a problem we are having.

Shell and Tube exchanger over time has developed low heat transfer issue. Cooling water is on the shell side. Delta T has decreased from 12C to 2C over the past few months.

Now suspecting the cooling water side of the tubes have lost effectiveness due to fouling maybe from calcium. Initial thinking is we could mix diluted HCl and do an acid soak. The material of construction is carbon steel.

Anyone have an idea on the strength of the HCl and soaking times?
Also any other ideas for cleaning?

Thanks,
K

 

[moltenmetal]

You want an inhibited de-scaling solution for sure if your MOC is carbon steel. Don't just use dilute HCl.

Is it carbon steel for both tubes and shell?

 

[ash9144]

Use an industrial cleaning contractor for this. Mixing a weak acid and putting it into a carbon steel HEX is risky business. The contractor will use a dilute citric acid solution and track amount of iron present in the solution to track how much metal is being removed. You also need to know if this has been done to this exchanger before. There is a limited number of times you can acid clean an exchanger before reaching min thickness of your tubes. After cleaning it would be smart to eddy current test your tubes.

 

[yumeteor]

After you clean your system I would recommend using a self-cleaning water filter like the Forsta filters.

It will keep your system clean from particles in the future.

http://www.forstafilters.com

You might want to ask them to size the filter for you.

 

[weeeds]

Can you not remove the bundle for proper inspection and cleaning as is common practice?

 

[unclesyd]

If you are going to do it yourself i strongly recommend the use of Rydlyme. This is weak HCl cleaner with superior additives.

http://www.rydlyme.com/home.html