What is the function of desalter?

A desalter is a process unit in an oil refinery that removes salt from the crude oil. The salt is dissolved in the water in the crude oil, not in the crude oil itself. The desalting is usually the first process in crude oil refining.

What is desalter water?

Desalter effluent is a combination of many things such as: brine washing water used for removing salt, sand and mud washing water jet used at periodic intervals, connate water produced from the reservoir with crude oil. Desalter’s wastewater contains oil, demulsifier, and oxygen scavenger.

How does a refinery desalter work?

In the desalter, the crude oil is heated and then mixed with 5-15% volume of fresh water so that the water can dilute the dissolved salts. The oil-water mix is put into a settling tank to allow the salt-containing water to separate and be drawn off. Frequently, an electric field is used to encourage water separation.

What is naphtha in refinery?

Naphtha (often referred to as naft in the older literature) is a generic term applied to refined, partly refined, or an unrefined low-to-medium boiling petroleum distillate fraction. Naphtha resembles gasoline in terms of boiling range and carbon number, being a precursor to gasoline.

Why salt is removed from crude?

Crude oil introduced to refinery processing contains many undesirable impurities, such as sand, inorganic salts, drilling mud, polymer, corrosion byproduct, etc. The purpose of crude oil desalting is to remove these undesirable impurities, especially salts and water, from the crude oil prior to distillation.

How do you separate crude oil from water?

Commercial methods for breaking emulsions include settling, heating, distillation, centrifuging, electrical treatment, chemical treatment and filtration. These separation technologies can be used in combination to secure optimum results. Emulsions can be classified as oil-in-water and water-in-oil types.

How is salt removed from crude oil?

To remove the salt and the water, crude oil undergoes a step known as desalting. In this step the crude oil undergoes an initial dilution with the addition of clean water. The new diluted mixture is then emulsified so that the salty water initially present in the crude oil comes into contact with the clean water.

How does oil desalter work?

Which apparatus is used for separation of oils from water?

An oil water separator (OWS) is a piece of equipment used to separate oil and water mixtures into their separate components. There are many different types of oil-water separator.

How does electrostatic dehydrator work?

The basic principle behind electrostatic dehydration is that an electrical field is used to excite droplets of brine within the bulk oil phase so that they collide with other droplets and coalesce into larger globules that separate under gravity.