Rupture disc location on batch reactor

[KLEQ]

Hi community!

I am working in a chemical plant which produces resins in batch mode in reactors.

Most of the reactors are protected by a rupture disc located on a dedicated line on top of the vessel.
Some of them are also protected by a rupture disc but the location is different and I am not 100% confident on this location.

Please refer to the attached file: the rupture disc is located on a line that is connected to the reactor through a vent line by a tee.

http://files.engineering.com/getfil...-3a38-4f4e-bfe5-b16003fac5a7&file=Capture.PNG

My question is: do this connection is acceptable? I don't see any recommendation on API 520.

Cheers,

Kevin

 

[Latexman]

This connection is acceptable by Code, if the RD relieves the worst case scenario. The difference between this and a dedicated line is 1 branch tee, 1 elbow, and possibly a short length of pipe. Personally, I would prefer the manual vent line be on the branch tee and the RD on the straight run, making the RD equivalent to the dedicated lines.

Good luck,
Latexman

To a ChE, the glass is always full - 1/2 air and 1/2 water.

 

[georgeverghese]

You should check if there is a possibility of a blockage at the RD inlet or the upstream tee (due to polymerisation , decomposition etc), if there were to be some routine tank manual venting operation.

 

[StoneCold]

We will share the vent and rupture disk line on a reactor. However, like Latexman we prefer the rupture disk to be on the straight run and the vent to be on the branch.

Regards
StoneCold

 

[KLEQ]

Thanks a lot for your answers that make me more confident in the design and I agree that rupture disk shall be on the straight run.

Regards,

Kevin

 

[moltenmetal]

Plugged rupture disc inlet lines give me nightmares. In a polymerizing system which could go auto-thermal, having a reliable passive pressure protection safety layer is critical, and that relief has to be reliable.

The issue of polymerization in the rupture disc line can be a serious one or a trivial one depending on which "resins" you're making. In the case that the rupture disc shares the vent, you will at least know when that line is plugged, but of course you'll be in big trouble on that day! You will also be carrying monomer in the vent gas past the rupture disc where, depending on the monomer system, it might condense and polymerize over time.

The best option is a flush-mounted (so-called "extruder style" rupture disc which is flush with the inner surface of the top head.

 

[silebi66]

Dear KLEQ

The rupture disc(PSE) often be equipped with relief valve(PSV) if the discharge fluid is viscous or corrosive. It is installed before the PSV intended to block the viscous or corrosive fluid to enter the PSV to increase the PSV downstream back pressure if system overpressure occur.

Some consideration in locating this PSE is near the operation and maintenance access to operator and prevent any liquid seal formation which would obstruct the relief flow to the system.

Hope this is make sense.