What is the use of fractionating column in fractional distillation

A fractionator column, also known as a distillation column, is a key component in the process of separating a mixture of different components based on their boiling points. The column is essentially a tall tower filled with trays or packing materials, where the mixture is heated and vaporized. As the vapor rises through the column, it gradually cools and condenses on the trays or packing materials. The condensed liquid is then collected and separated into its individual components.

The fractionator column is widely used in the chemical and petrochemical industries for various applications such as crude oil refining, natural gas processing, and chemical manufacturing. In this article, we will discuss the working principle of a fractionator column, its components, and the factors that affect its efficiency.

Working Principle of Fractionator Column

The basic principle behind the functioning of a fractionator column is the difference in boiling points of the components in the mixture. The mixture is heated and vaporized in the bottom section of the column, known as the reboiler. The vapor rises through the column and is cooled by the cooler surfaces of the trays or packing materials. As the vapor cools, the components with higher boiling points condense back into a liquid and settle on the trays or packing materials, while the components with lower boiling points continue to rise.

The trays or packing materials in the column provide a large surface area for the vapor to come in contact with, which facilitates the transfer of heat and mass between the vapor and the liquid. The trays are usually perforated plates with holes that allow the vapor to pass through and mix with the liquid on the tray. The packing materials, on the other hand, are usually made up of small particles or structured materials that provide a large surface area for the vapor-liquid contact.

As the vapor rises through the column, it passes through a series of trays or packing materials, each of which is designed to perform a specific function. The trays are designed to enhance the separation efficiency of the column by providing a large surface area for the vapor-liquid contact and allowing the liquid to flow from tray to tray. The packing materials, on the other hand, provide a greater surface area for the vapor-liquid contact and create a tortuous path for the vapor, which improves the separation efficiency.

The fractionator column is equipped with a condenser at the top, which is used to cool and condense the vapor back into a liquid. The condensed liquid is then collected in a series of trays or in a sump at the bottom of the column. The liquid is then routed to a series of separators, where it is separated into its individual components.

Components of Fractionator Column

A fractionator column is made up of several components, each of which is designed to perform a specific function. The key components of a fractionator column include:

Reboiler: The reboiler is located at the bottom of the column and is used to heat the mixture and vaporize it.

Trays: The trays are located at regular intervals along the column and are used to separate the components based on their boiling points. The trays are usually perforated plates with holes that allow the vapor to pass through and mix with the liquid on the tray.

Packing materials: The packing materials are usually made up of small particles or structured materials that provide a large surface area for the vapor-liquid contact. The packing materials create a tortuous path for the vapor, which improves the separation efficiency.

Condenser: The condenser is located at the top of the column and is used to cool and condense the vapor back into a liquid.

Sump: The sump is located at the bottom of the column and is used to collect the condensed liquid.

Factors Affecting Efficiency of Fractionator Column