Dear all,
I am trying to do the depressurizing calculation for a flowline. There are two scenarios available for depressurizing of this flowline, Summer case and Winter Case.
The summer case I used to size the vent line and orifice (depressurizing will be done manually).
My first question is regarding the winter case. If I assume that the natural gas at temperature of 92C is trapped in the flowline at pressure of 350 barg and then it is cooled down to ambient temperature which is -4C. Then what will be the pressure in the flowline. The natural gas contains some water as well.
My second question is; I will have ice/hydrate formation in the winter case. What is common to do in this situation? Should I consider Methanol injection prior to shut in the flow line?
Thanks,
ARM