There are three liquid ammonia vessel operating at pressure of 5 kg/cm2g, 2.5 kg/cm2g and 20 mmHg respectively. From the top of ammonia vessels, vapor ammonia lines are going into the Ammonia compressor at different stages. In the vapor ammonia line, relief valves are provided. The capacity of Relief valves are as below.
1st vessel (Operating pressure - 5 kg/cm2g) - 6000 SCFM Air
2nd vessel (Operating pressure - 2.5 kg/cm2g) - 12900 SCFM Air
3rd vessel (Operating pressure - 20 mmHg) - 900 GPM Water
My queries are.
1. Why the Relieving capacity mentioned in terms of SCFM of Air or GPM of Water and why not in terms of Ammonia?
2. Why the Relieving capacity of two vessels in SCFM of Air and Relieving capacity of one vessel in GPM of water?
Regards
Alok