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Hysys Calculation

Hysys Calculation

Hysys Calculation

Hi everyone,

I have a question relate to the Hysys. fro example when pressure control is fail close it can cause the pressure in vessel rises( back flow pressure).so I want to Convert PI to a transmitter and add a high pressure alarm. For this to count as a layer of protection we would need to check how fast the pressure rises if PV fails closed – there needs to be enough time for the operator to react to the alarm.
that we can you Hysys to calculate time? if we can use Hysys, can you give me the step or any example relate to this problem?


Best Regards


RE: Hysys Calculation

This is a dynamic process so you have to use Hysys Dynamics for simulation of vessel pressurization.

Configure the vessel (dimensions, volume), inlet and outlet streams, conditions etc. in steady state first (normal operating conditions).
Each stream should have a control valve with known Cv: PCV on gas outlet, LCV on liquid outlet, and use e.g. FCV for the feed stream.
Then, set the overhead PCV manually to go into fully closed position and monitor pressure rise inside the vessel.
There are nice examples in Hysys Dynamics Manual. See attached file and also https://www.ualberta.ca/CMENG/che312/F06ChE416/Hys... - all this is available online.

Process Engineer, MSChE

RE: Hysys Calculation

You can use dynamic simulation in Hysys to model the problem. See the Hysys manual or contact Hysys helpdesk.

RE: Hysys Calculation

Thank you so much #EmmanuelTop and #Berenger.



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