Relief valve placement for Thumper

[Zubehor]

Hope you all doing well, I´m currently revisiting my designs for a 15.5 keg Boiler+ 15.5 keg Thumper Steam Injector setup for Stripping and such.

Actually I will discribe the whole process I´m going for.

1.- Stripping Runs: Clear wash into boiler and dirty grain/wash into thumper with steam Injection (nothing new about this)
2.- Neutral Run: VM 3" column attached to either boiler or boiler+Thumper ( here I need your wisdom ) is it worthy to use the boiler+thumper with VM Column?
3.- Gin Run: Clear liquid from maceration into boiler + botanical basket into thumper for flavouring to a 3" inch pot head.

Modularity is my way of thinking here. The Thumper will have a 8" to 3" milk can lid bought from Mille High. So I can switch from the 3" VM to the Pot Head and the ease of cleaning the Thumper. Also I plan on doing a 2" with 4x1/2" shotgun condenser, long enough to condensate full throttle stripping Runs and Spirit Runs.

The Problem I have right now is the design of an overflow and pressure/vaccum Releif valve between the Boiler and Thumper.

In the image below I drew some ideas. (sorry the english and the drawing skills) Hope you can understand it.

First is the Location of the Relief valve. Either on the Steam pipe that goes into the thumper, or placed on the overflow return to the Boiler. Both this options concern me about the possibility of releasing alcohol vapor to atmosphere. Forgot to mention I plan on using open flame (gas burner).

Second would be IMHO the best choice wich is a pressure/vaccum ball valve from the Steam Pipe into the Column wich would be open to Atmosphere.

Long post but hope you can help me clarify and avail my preliminary Design. Many Thanks in advance for sharing so much knowledge.

Best Regards from Chile

IMG_20200222_134047.jpg