I have a pressure regulator to maintain a specified pressure in a vessel that also contains a liquid. The regulator can pressurize or relieve pressure of the vessel. I want to prevent the liquid from flowing back to the regulator while keeping the gas flowing both ways. I can imagine a device that would do that but can't find a readily available one on the market. Any ideas?
I thought simplifying my problem was gonna help but now I'm thinking that sharing the exact context of my situation might help you help me. So, this situation is happening on a counter-pressure beer canning machine (cheers!) The pressure regulator maintains a set pressure of CO2 in the machine's can filling tank. The level of beer is this tank is regulated by an actuated globe valve and the beer transfers from the BBT to the machine's tank by a differential pressure between the two tanks. During operation, the regulator has to supply and relieve pressure from the machine's tank (two-way flow). My issue is that if for any reason the beer supply valve doesn't close completely, the beer level rises up to the CO2 supply port, eventually overflows right into the regulator and ruins it...so as a safety, I want to install a check valve that would only close in the presence of liquid (beer) while allowing gas (CO2) to flow both ways the rest of the time.