The process of separation of components in the chemical industry

Stem stripping:

Steam stripping is a distillation process where the heavy product is water, and the light products are the mixture of volatile organic substances. The volatile substances have a very strong influence on the temperature thus high temperature that is present in the stream allows the separation of this volatile material which is otherwise impossible to be removed by any process.

The main advantage of using a stripping column is that it gives better performance under a reduced electricity cost. The contemporary designs are being connected with the computer simulations and in-house pilot plant testing.

 

Principal of stream stripping:

A pre-treated and heated component is made flow from the final heater to the distributor on the top of the column. The flow of the component is either forced by gravity or external pressure. Once the component is being transferred to the distributor, the distributor lets that component distribute in the cross section of the column. The component is then passed through the structured package till it reaches the bottom of the column. The oil in the column meets the stripping steam in a counter current flow. The column is under vacuum thus, the exposure of the column under the high temperature in the vacuum lets the removal of the volatile material from the component.

Principal of liquid-liquid extraction:

The basic use of liquid to the liquid extraction of components (Solutes) o be recovered from the liquid stream (Carrier). The two liquids must be immix able or slightly mixable to allow them to form a dispersion. Thus, one liquid disperses as a droplet in another. After that, the process moves to dispersed phases where a mass transfer occurs between the droplets alongside a continuous stage of the surrounding liquid.  The droplets then accumulate above or below the continuous phase, depending on the liquid's relative densities. There is a boundary between the continuous phase and the dispersion phase this is called the interface which can be located at the top or the bottom of the extraction column.

Usage:

Liquid-liquid extraction is the most commonly used technology used for the extraction in the chemical industry. While distillation uses the boiling point differences for the separation of components, the liquid-liquid extractor uses the mixibility of two different liquid for its separation. When there is an option of extraction available the extraction is chosen over the distillation as it extraction is a cost efficient process.

Source : articlesbase.com