sargon:

A reliev valve is a connection to atmosphere with is an out for your system which would mean its not a closed loop anymore.  What is the system used for and are there any demands on the system that will use flow?  The use of the bladder tank will mean that pressures will keep stable around your set point so the demands will be critical to meeting your suction pressure requirement.

give us a bit more info...

BobPE

Sargon!

You can do it with specifying your back pressure (what ever it is) on the relief valve when you order it. There are Back Pressure Control Valves already available. Try one.

Regards,

Repetition is the foundation of technology

Not sure what the problem is:  If you provide a pump (or pump and throttle valve) that produces 54 psig, you'll have enough pressure at your first use point, and with a drop of 32 psi you will have enough at your last use point = 22 psig. (?)     If however, the flow in the system will vary due to different demands then the 32 psi will vary.  To keep the presure to the last piece of equipment relatively constant at 22, you would install a  pressure regulator in the branch from the loop to that equip. set at 22 psig.  (a relief valve is not appropriate)   In that case the pump can be set to discharge as high as the 60 psig