Hello all,

I have a question related to relief temperature. How to find out relief temperature for different scenarios , viz. reflux failure or CW failure or power failure for a column overhead PSV.

Thanks

Koushik

The temperature will be coincident with the pressure. You would use the temperature of the vapor by simulating the higher pressure in the tower. Using a proceess simulator will greatly help, and in some cases it will be almost impossible to get it correct without one. For vapors in a reflux failure get the temperature at the top of the column when the tower goes into relief simulating the column with no reflux. You can take credit for condensing though in this case. Cooling water failure is similar. You loose the condenser but the column still operates with reflux for a period of time until the reflux drum is depleted. Then this becomes a reflux failure case without the condensing credit you took before.

It's all in how you set up your simulation.