Best Practice - PRV valve on top or on CIP arm?

[ccrabtree]

We currently have tanks (FV and BT) with the PRV valve on the CIP arm. It is an adjustable pressure/vacuum valve. I am curious what the opinions are about safety with this configuration. Any comments from experienced brewers, engineers, etc. would be appreciated.

[Ted Briggs]

ITs the best practice assuming you have a separate blow-off arm and you valve off the cip arm during fermentation. No risk of prv getting clogged with Krausen and one less reason to climb to the top of the tank.

Edit- PRV on the blowoff arm at 90deg, ie on a t'. Id also like to see Ruture disks become standard practice.

[TGTimm]

Belt and suspenders. All of our ferms have both a PCV--for spunding--and a PNRV to protect the tank and our workers. The PCV (pressure control valve) is located low on the blow-off arm, the PVRV either on the top of the ferm or on the CIP arm, with the theory that the CIP ball will act as a filter to keep the PVRV from clogging.

Mounting on top of the ferm is inconvenient unless you have a top deck to work from.

[dick murton]

To largely echo the other comments, if you have the antivac valve on the CIP arm, you are effectively blocking it off completely whenever there is liquid in the CIP supply pipe, so making it inactive during CIP. And guess what? One of the critical times you need protection from a vacuum is during CIP - to protect against caustic/CO2 reaction reducing the pressure, or against the supply being restricted during periods of scavenge only.

The same concept , but perhaps to a lesser extent re changes in pressure, applies to the PRV

Stick the anti vac valve and PRV on a separate line to the tank, or on the tank itself.

[ccrabtree]

Thanks for the opinions

Thank for the opinions. It helped a lot.

[gitchegumee]

Tank itself....

I stay away from mounting safety valves on a CIP line. In the past I have found CIP balls totally clogged with krausen precisely because they have small holes. And those small holes won't relieve vacuum nor pressure to the same capacity as a full bore pipe. Not tolerated by ASME code--the SRV should also be one size larger than the largest line that adds or drains product. And you should never install SRVs after another valve--such as ball or butterfly--that could possibly defeat the SRV.

[grnis]

Good manufacturing practice dictates that tanks has a vacuum breaker on the top, one dimension larger than the tank outlet, also a sealed spring or weight loaded safety valve, also on the top. There are tank top assemblies that combines all of these, together with CIP-connections and CO2-outlets.

The bunging apparatus is located on the gas supply/outlet pipe and it is adjusted as needed.