Control between VRUs

[Zhihong.han]

We are adding a larger VRU skid to an existing facility that has a smaller VRU skid.

I am looking for help about the controls and split flow strategy for the two VRU skids.

If we run all the flow through the new bigger skid and only use the old smaller skid when required what is the best control strategy . Should we add a control valve only at the inlet of the smaller old skid and that opens when the outlet pressure of the new VRU drops or does anyone recommended adding a control valve at each VRU inlet piping

Appreciate any feedback

 

[Rubje]

You can indeed consider to run all of the flow through the new, larger VRU skid, and only use the old, smaller VRU skid when required. In this scenario, you could install a control valve at the inlet of the smaller VRU skid that opens when the outlet pressure of the new VRU drops below a certain level. This would allow you to maintain a relatively constant pressure across the system, while also ensuring that the smaller VRU skid is only used when really necessary.

Alternatively, you could consider installing control valves at the inlet piping of BOTH VRU skids. This would allow you to adjust the flow rate of each VRU independently, based on the demands of the system. For example, you could open the control valve for the new VRU skid when the flow rate is high, and open the control valve for the smaller VRU skid when the flow rate is lower. This would allow you to fine-tune the performance of the VRUs, and ensure that the system is operating as efficiently as possible. This is done with many compression systems.