Fig. 8 shows the hydraulic capacity diagram of the system palm fatty acid distillates. For all the isotherms, the gas capacity factor FV = f(UL) decreases as the pressure increases, holding the liquid load constant. This is probably due to the fact that the density difference between the coexisting liquid and gaseous phases = (L − G) becomes smaller as the system pressure increases. For all the isobars, the gas capacity factor FV = f(UL) increases as the temperature increases, holding the liquid load constant. Once more, the effect of density difference between the coexisting liquid and gas phases seems to predominate over the effects related to physical property variations. The hydraulic capacity diagram represented by Fig. 8 has the advantage that the effect of both temperature and system pressure on the maximum capacity point of packed columns can be easily visualized.