A kind of pretreatment process method of high-acid crude oil

Abstract

The invention relates to a pre-treatment process method of high acid crude oil. The method comprises the following steps that high acid crude oil is treated by coupling deacidification and electro-desalting processes by combining chemical extraction and electro-desalting; a first level tank is taken as a deacidification and electro-desalting tank; a demulsifier and an extractant are injected before a crude oil electro-desalting static mixer; after being fully mixing with crude oil, the mixture enters into the first level desalting tank; generated naphthenate and salt-containing sewage in the crude oil are dissolved in the extractant; treated deacidified oil enters into second and third level desalting tanks after being mixed with the demulsifier and water through the static mixer for desalination and dehydration; treated crude oil enters into a subsequent heat exchange unit; after a period time of operation of an electro-desalting system, impurities such as mud in raw material oil are flushed by a non-stop back purge device to discharge mud-containing sewage out of the tank; an extract phase is acidified to separate out naphthenic acid which is further extracted and purified by light dydrocarbon, and the extractant is purified and recovered and recycled.

Description

Technical field [0001] The invention belongs to a method for removing petroleum acid, salt and water in crude oil by coupling high-acid crude oil chemical extraction and electric desalting. technical background [0002] With the depletion of oil resources and the continuous improvement of oil recovery technology, a large amount of high-acid value crude oil has been extracted. At present, the output of high-acid crude oil in the world crude oil market accounts for about 5% of the total global crude oil output every year, and the annual growth rate of 0.3 % growth rate. In 2009, the global high-acid crude oil production exceeded 400 million tons, accounting for 10% of the total crude oil production; my country's high-acid crude oil production was about 57 million tons per year, accounting for about 30% of the country's total crude oil production. During the refining process, the naphthenic acid contained in the high-acid crude oil can cause corrosion of the refinery unit, whi...

AI Technical Summary

Problems solved by technology

[0005] Neutralizer, solubilizer, water and demulsifier are added to the crude oil or distillate oil and fully mixed with the oil, then enter the electrostatic oil-water separator to generate naphthenate and enrich in the emulsified layer of the container, and the emulsified layer is separated from the electrostatic The device is pumped out into the secondary electrostatic oil-water separator for oil, water and naphthenic acid separation. This process emulsifies the emulsification layer of the aqueous solution seriously, and further separation is difficult.

[0006] In general, high-acid crude oil has high density and high viscosity, and there is no suitable process to combine deacidification and desalination

Images