7 replies to this topic

[Sharma Varun]

We are in discussions with client, where in an offshore revamp project, they are envisaging a single vessel serving purpose of both flare KOD & closed drain drum (i.e. it collects all maintenance drains from the platforms + few contineous process drains).

As per client, they are already having such kind of arrangement at one of there installations.

 

This is a new concept for me & I am studying the same, the purpose of posting to this forum is to share the idea & get different opinions/views.

 

Particularly, I am looking for a feedback suggesting what extra precausions shall one take while designing such a system & if there are any hidden safety flaws, which we are ignoring in going ahead with design.

[Sharma Varun]

I managed to get one more reference of this kind, seems like this is an established practice.

Edited by Sharma Varun, 25 November 2013 - 04:43 AM.

[Erwin APRIANDI]

Hi Sharma,

 

This is common practice but not all operating company will accept this especially those who are really concern on safety.

By using the Flare KOD as a Closed Drain, there will always a possibility of having the KOD is having some liquid and then you have to size the KOD bigger in order to achive the required Knock Off function of KOD.

 

I have similar design before, and there is always a question that may be raise especially during HAZOP, so make sure that you can defend the design during the HAZOP.

 

Best Regards

[Sharma Varun]

thanks Erwin Apriandi,

 

Your concern is noted, but in my case client himself is asking for this design & I have taken care of drain inventory as a requirement in addition to levels req. for normal KOD & liq. hold up requirement for worst liq. carry over based on residence time as per client standard also meeting vapor space criteria req. for flare KOD.

 

Since you have past experience can you tell me if I have to consider any thing else (aprt from hold up requirement & sizing) w.r.t. safety, by any known code or anything which might have come up during HAZOP. Any more detail will be helpful.

[Sathya R]

For all sattelite platforms our design- the CDV and FLKOD service will be served by one vessel.  It will advantages if we can combine LP Flare KOD with CDV for CPP.The sizing shall be accordingly. Refer to api 521.

[Erwin APRIANDI]

Hi Sharma,

 

As what Sathya has mention, the sizing will be based on API STD 521.

Some consideration that you have to be taken care of is

- To prove that the HP/LP Interface of your process drainage line to the KOD is well protected

- To prove that the back pressure of KOD is not reaching more than the design pressure during possible gas blowby from process drain (since you said there is continous drain)

- etc, I can not find the HAZOP report, and it has been 5 year past, hope other can help

[Sharma Varun]

 

Yes I am following API 521 for sizing basis, thanks  to both of you Erwin Apriandi & Sathyanarayanan Ramamurthy your inputs are well received.

[Purnesh Meshram]

Hi Guys 

Very nice information additionally if any one can share HAZOP of it would be wonderful.

 

thanks