What does vented energy refer to in gas releases?

• A. Energy stored in the vent equipment only
• B. Only kinetic energy
• C. Energy carried by released mass including latent heat and chemical energy
• D. External heat applied during venting

Answer: (C)

Vented energy is the energy carried away by the gas as it is released. When gas vents, the stream has energy in several forms that leave with it: the internal and enthalpy energy of the gas, any latent heat from moisture or phase changes, and any chemical energy stored in the gas or its potential reactions. This total energy carried by the vented mass is what’s being referred to, not just the motion (kinetic energy) or energy stored elsewhere.

If you only consider the equipment or external heat input, you’d miss the actual energy that exits with the gas itself. The option that accounts for all forms carried by the released mass—latent heat and chemical energy in addition to sensible energy—best captures vented energy.