Cost effective methods to prevent significant pressure losses for compressed air from heavy users?

[YungPlantEng]

My site uses regulated compressed air to unload our rail cars to pump maybe around 200 gallons a minute (30 acfm at 40 psig) to storage. During the end of unloads vortex formation allows air to go directly through without the typical downstream pressure of the fluid being unloaded such that the acfm spikes to what’s essentially a 1” line leak.

I wanted to find some sort of backpressure regulator that would prevent the pressure upstream of this line from going below a certain amount. Ideally something that doesn’t need to be reset each time it triggers. Any ideas?

 

[LittleInch]

Draw this out can you?

using compressed air to unload usually comes up against what happens at the end, but it's not solved by pressure.

YOu should be able to install some sort of flow control device to limit flow into each rail car?

And / Or introduce anti vortexing equipment inside the rail car.

 

[Snickster]

Excess flow valves are commonly used. Some codes actually require installing them in lines such as filling stations.

Excess Flow Valves | Total Valve Systems

1 (800) 324-7035 | Excess flow valves are designed to close when a sudden flow surge occurs.

www.totalvalve.com

 

[Compositepro]

It is not clear whether your are using the air to power an educator for unloading, or you are pressurizing the tank car to unload it. I'm guessing the latter, as compressed air flow to an educator would not increase when the tank empties. You need to use a restrictive orifice in the air line between the pressure regulator and tank car. This will also limit the flow when first pressurizing the tank (which is likely higher than when the tank empties). There are a number of hazards in using compressed air to unload in this way. What you mention is only one of them.

 

[georgeverghese]

There is no need to reset anything on a typical self operated backpressure regulator.