What is a crude oil desalter?
What is a crude oil desalter?
Desalting involves mixing heated crude oil with washing water, using a mixing valve or static mixers to ensure a proper contact between the crude oil and the water, and then passing it to a separating vessel, where a proper separation between the aqueous and organic phases is achieved.
What is the temperature of electric desalting crude?
They found that for high performance the temperature between 115°C and 120°C is required. The amount of injected chemicals which gives a high desalting efficiency is (50 to 100) ppm of demulsifiers noted (C and F). Suitable pH range of crude oil associated water is between 9 and 12.
What is the function of the desalter unit?
A crude oil desalter is a device used in petroleum refineries to remove inorganic salts, water and sediment from the incoming petroleum crude oil feedstock before it is refined. This article focuses on the use of electrostatic desalters to produce a dehydrated, desalted crude oil with a low sediment content.
How does a 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 are the types of desalting process?
Desalting process Emusification of diluted water in oil. Distribution of the emulsion in the electrostatic field. Electrostatic coalescence. Water droplet settling.
Why should salts be removed from crude oil before refining?
Crude oil emulsion is formed as dispersed water phase in an oil medium. The water globules are protected by an oil layer which prevents their coalescence. Both the water phase and its dissolved salt contents need to be removed because they lead to corrosion in the refinery equipment.
What is crude salt?
Salt in crude oil is typically in the form of salt crystals dissolved in the water that is emulsified in the crude oil. The most common salts are chlorides of sodium, calcium, and magnesium. High concentrations of salt in a crude oil grade will affect its market value because of the additional cost of processing it.
What are the 3 methods of desalination?
Desalination technologies The three major, large-scale thermal processes are multistage flash distillation (MSF), multi-effect distillation (MED), and vapor compression distillation (VCD). Another thermal method, solar distillation, is typically used for very small production rates.
What is pour point of diesel?
CFPP is the temperature at which or under which diesel fuel cannot flow through a filter in a certain time. Cloud point is defined to be the temperature at which the first crystal is formed while pour point is defined as the temperature at which the liquid ceases to flow [[7], [8], [9], [10]].
What is the difference between pour point and freezing point?
Pour point is the temperature at which a petroleum product will no longer flow. Freezing point is a measurement of the lowest temperature at which an aviation fuel will remain free of solid hydrocarbon crystals that could restrict the flow of fuel through filters.
How is salt removed from crude oil?
Crude oil to be desalted is heated to a temperature of 100-150 °C and mixed with 4-10% fresh water, which dilutes the salt. The mixture is then pumped into a settling tank where the salt water separates from the oil and is drawn off.
Why do we use desalter in crude oil?
Crude Oil Desalting technology is utilised to remove residual salt to meet these requirements. The type and size of the Desalter that is used is dependent upon a number of fundamental factors such as pressure, temperature, fluid viscosity and flow-rate, as well as customer requirements relating to maximum salt allowed in the product oil stream.
What is the water content of a desalter?
When a desalter has been well-designed and well-operated, it will achieve an average of 85 to 95% removal of inorganic salts from the crude oil and the water content of the desalted crude oil will be less than 0.2 volume percent of the crude oil. 1.0 1.1 1.2 1.3 1.4 1.5 Jean-Pierre Wauquier (Editor) (2000).
How is the sediment at the bottom of the desalter withdrawn?
The settled sediment at the bottom of desalter is withdrawn as a sludge at intermittent intervals as needed to prevent solids from entering the settled water withdrawal outlet. Figure 1: Schematic flow diagram of a typical crude oil distillation unit.
What is the meaning of the term desalter?
The term desalter may also refer to a water desalination facility used to treat brackish water from agricultural runoff.