cooling tower at lower position

[carlanox]

Dear all,

I have a case where the cooling tower location is 15m lower than then PHE unit it is connected to. The issue is during the filling or when the pump power off, all the water at higher level area will flow back into the cooling tower.

Do I need to add check valve to prevent water flow back into the cooling tower basin or is there any other solutions?

thanks

 

[nuuvox000]

Check valves no good because it's the same direction. I've heard some people use a motorized control valve and have it control the valve to close and then the pump shuts off.
You can also pipe in a tall 15m trap if you have room for it.

 

[SAK9]

Good suggestions by Nuuvo.The problem with motorised valve is it takes time to close unless you can find a fast acting valve.I have seen the trap solution being used in few places. Also consider the installation of a backpressure regulator valve near the cooling tower on the return line.I am not sure if the backpressure valve provides 100% tight shut off when the pumps shuts down. You may need to speak to a vendor to check on it