High salt content in crude oil

To address the high salt content in crude oil, the following measures can be taken: 1. Increase the combined pressure drop for electrodialysis desalination； 2. Increase water injection ； 3. Increase the temperature before power supply desalination ； 4. Increase the dosage of the demulsifier or change its formula ；

Water injection volume: Victory high-sulfur, high-acid crude oil is characterized by high sulfur content, high acid value, as well as high salt and water levels. An appropriate amount of water is injected into the crude oil to dissolve the salts, and under the influence of an electric field, these salt-containing water droplets coalesce. For the Shengli high-sulfur and high-acid crude oil, a relatively large amount of water is required for injection; this is necessary to achieve dehydration and desalination of the crude oil. In operation, the amount of water injected in the second stage is 35 tons per hour, accounting for 4.5% of the total crude oil processed. The water removed in the second stage is then reinjected into the first stage. Under these operating conditions, increasing the amount of water injected leads to an increase in the current in the electrodesalination tank and a decrease in voltage, indicating that the excessive amount of water causes excessive emulsification of the oil and water phases. This results in an thicker emulsion layer between the oil phase and the water phase, making it difficult to supply electricity to the electrodesalination tank. At the same time, the saline wastewater produced contains a high amount of oil. When electrodialysis emulsification is not severe and the water content after secondary desalination is not high, tertiary water injection is resumed for reinjection in order to improve the desalination efficiency of tertiary electrodialysis and reduce the salt content after tertiary desalination.

Thank you! Two people! I also want to ask what methods are available to reduce water usage in crude oil with a high salt content at present?

I would like to ask why increasing the mixed pressure drop can reduce the salt content in crude oil? Please, brother, explain the principle behind each measure. Thank you!

What is your normal desalination rate?

The pressure drop of a mixing valve refers to a mixing valve whose opening degree affects the degree of mixing between crude oil and water. If the opening degree is too low, the crude oil and water cannot mix sufficiently, making desalination difficult; if the opening degree is too high, the mixing between crude oil and water is excessive, which also hinders the desalination process. Put simply, salt is mainly an inorganic substance that dissolves easily in water. If the opening of the mixing valve is small and the crude oil does not mix thoroughly with water, less inorganic salt is absorbed by the water, resulting in poor desalination efficiency. When the opening degree of the mixing valve is high, crude oil and water mix excessively; salts can attach to other molecules, reducing the amount that dissolves in water. As a result, the desalination effect is poor. In the operation of normal systems, a suitable opening degree for the mixing valve is determined based on the composition of the crude oil and the amount of water injected, and this degree hardly changes.

Optimize the heat exchange network and increase the operating temperature of the electrodialysis tanks; at the same time, select an appropriate water injection rate – around 3.8% for secondary injection and about 2.5% for primary injection. Use high-quality demulsifiers. As the temperature rises, the solubility of inorganic salts in crude oil in water increases, which helps to improve the desalination efficiency

Select an appropriate demulsifier based on the crude oil, and choose the right product according to the compatibility of the demulsifiers