Andrehzg
Chemical
- Mar 2, 2015
- 2
Hi,
I´m working at the time in a project in wich we must consider an VRU to recover the HC vapor from the cold vents (blanketing gas) of the tanks.
I´ve been wondering about the process design basis to do this. I have several tanks in the area. And as the API 2000 recomends, we estimate the blanketing outbreathing gas to prevent oxigen to come into the tanks and safeguard the structural integrity of them.
Knowing this, the issue that we have is which should be the real process design basis of the VRU which recovers the HC vapors from these tanks. It is not real to assume that all the outbreathing flow will go simultaneosly to the VRU as the tanks have level control set in a normal operation level, so it is not real to assume either that this leve will fail in several tanks at the same time.
Resuming, my question then is which would be a conservative flow to be considered to design the VRU if we have several tanks connected to this systems, this tanks operates at a normal liquid level usually. I assume that there should be some prerrogatives we can assume not to over design this unit, as we do when we design a flare system.
Thank you in advance
I´m working at the time in a project in wich we must consider an VRU to recover the HC vapor from the cold vents (blanketing gas) of the tanks.
I´ve been wondering about the process design basis to do this. I have several tanks in the area. And as the API 2000 recomends, we estimate the blanketing outbreathing gas to prevent oxigen to come into the tanks and safeguard the structural integrity of them.
Knowing this, the issue that we have is which should be the real process design basis of the VRU which recovers the HC vapors from these tanks. It is not real to assume that all the outbreathing flow will go simultaneosly to the VRU as the tanks have level control set in a normal operation level, so it is not real to assume either that this leve will fail in several tanks at the same time.
Resuming, my question then is which would be a conservative flow to be considered to design the VRU if we have several tanks connected to this systems, this tanks operates at a normal liquid level usually. I assume that there should be some prerrogatives we can assume not to over design this unit, as we do when we design a flare system.
Thank you in advance
