Taking liquid gasification in distillation section as an example, the so-called minimum liquid-gas ratio is the ratio of the molar number of reflux liquid (liquid nitrogen in air separation column) and the molar number of ascending gas required to obtain pure products with low boiling point at the top of distillation section under the condition of unlimited number of trays.The parallel line parallel to the transverse axis starting from the gas phase composition of distillation feed is shown on the gas-liquid equilibrium data graph.This is of course not possible to draw operating lines and is a limiting condition.
