Distillation device is a tower type gas-liquid contact device used for distillation. By utilizing the property that each component in the mixture has different volatility, that is, the vapor pressure of each component is different at the same temperature, the light components (low boiling substances) in the liquid phase are transferred to the gas phase, while the heavy components (high boiling substances) in the gas phase are transferred to the liquid phase, thus achieving the purpose of separation. Distillation tower is also a widely used mass and heat transfer device in petrochemical production.