Writing different simplified forms of the energy balance, begins with the full equation:
(a) For a closed system with no changes in kinetic energy or potential energy, the energy balance becomes:
(b) For a distillation column operating at steady state, the energy balance becomes:
(c) For a closed system, the energy balance becomes:
(d) For an open system operating at steady state, the energy balance becomes:
(e) For a steady state reactor that operates adiabatically, the energy balance becomes: