[MW:665] RE: 664] Chemical cleaning for Marine boilers

Is it new equipment or used one? What is the purpose of chemical cleaning for your equipment? (I mean incase of used equipment what type of scaling involved, like water scales, iron oxide, and any other corrosion product/loose oxides?)

The principle of cleaning basically consists of circulating the desired chemicals through the Cooling Water Circuit by dosing them in the chemical dosing pot and maintaining circulation for a period sufficient to remove all the deposits.

Sriram!

Did u remember what we have done in BPB offshore for heat exchangers? What ever I could recollect I am putting down hereunder!

The procedure is elaborated as follows:-

CLEANING OF SHELL SIDE

1) Dosing of 2% Teepol B-300 into the Chemical Dosing Pot though which it is fed into the system.

2) The solution is circulated in the system for a period of 3-4 days during which KMnO₄value is tested.

3) On the completion of 4 days of circulation the system is to be progressively drained with simultaneous filling of fresh water.

CLEANING OF TUBE SIDE

This cleaning has been carried out by forming a closed circuit cleaning loop consisting of temporary piping and Recirculation Tank.

1) Filled and flushed the entire system with fresh water till clear.

2) 2% Teepol B-300 and 0.5% KOH added based on the system volume into the circulation tank. This solution is then pumped into the exchanger where it is allowed to soak for a period of 12 hrs.

3) The same solution is then circulated for a period of 8 hrs, after which it is drained and flushed till the PH is equal to that of the flushing water.

You can get the elaborated procedure from the chemical cleaning vendor, but remember it will vary for type of sediments what u needs to clean finally.

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of jagannathan Sriram
Sent: Wednesday, March 19, 2008 10:29 AM
To: materials-welding@googlegroups.com
Subject: [MW:664] Chemical cleaning for Marine boilers

Hi friends

If any one has procedure for chemical cleaning of marine boilers please forward to me.

Thanks

Sriram.

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