Method and device for removing salt for fractionate tower

Abstract

The invention discloses a method and a device for removing salt for a fractionate tower. The device is characterized in that a gasoline sump tank is arranged at an overhead recycle oil extraction position of a fractionate tower and an oil gas over line is arranged between the upper space of a lower layer tower plate of the gasoline sump tank and the front portion of an air cooler located at the top of the fractionate tower. The method is characterized in that when a salt removing process is carried out in a fractionate tower, oil gas in the upper space of the lower layer tower plate of the gasoline sump tank reaches the air cooler located at the top of the fractionate tower directly through the oil gas over line; a part of overhead recycle oil is cooled and then reaches the top of the fractionate tower and a part of the overhead recycle oil reaches the lower layer tower plate of the gasoline sump tank; naphtha in a gas-liquid separation tank located at the top of the fractionate tower is partly fed to a follow-up device and partly enters into the lower layer tower plate of the gasoline sump tank from the gasoline sump tank of the fractionate tower; wash water is injected from a overhead recycle oil return opening; and water for removing salt is discharged from an overhead recycle oil extraction opening. Through the method and the device, the advantages of no influence on fractionation effects of a fractionate tower and quality of gasoline and diesel oil products in salt removal, no influence on follow-up processes of rich gas compression, absorption and stabilization, simple operation, and good safety and reliability are realized.

Description

technical field [0001] The invention relates to the field of petrochemical industry, in particular to a method and device for washing salt in a fractionation tower. Background technique [0002] With the development trend of heavy and inferior crude oil, and the addition of oil recovery additives in the process of oil recovery, coupled with the factors of unstable electric desalination effect of atmospheric and vacuum devices, there are more nitrogen compounds in coking and catalytic raw materials And chlorides, resulting in salt formation in the upper part of the fractionation tower. Salt buildup in the fractionation tower will lead to an increase in the pressure drop at the top of the fractionation tower; the top circulation pump will not increase the volume, and the temperature at the top of the tower will fluctuate greatly. Large, unstable diesel output; diesel and gasoline quality deterioration and a series of problems. It brings difficulties to the safe and stable op...

AI Technical Summary

Problems solved by technology

[0006] In order to solve the problems in the prior art that the fractionation effect of the fractionation tower becomes worse during the salt washing process, the feed amount is reduced, and the subsequent gas compression and absorption stabilization system will be affected, etc., the present invention provides a salt washing process of the fractionation tower The method and device can isolate the top of the fractionation tower from the fractionation tower during salt washing, the salt washing process does not affect the fractionation effect, and the quality of gasoline and diesel products

Images