Method and system for preparing low-carbon olefin from crude oil

Abstract

The invention relates to a method and system for preparing low-carbon olefin from crude oil, and the method comprises the following steps: feeding crude oil into a first pipe group of a convection section of a cracking furnace for preheating, and then carrying out vaporization treatment to form a first vapor phase and a first liquid phase; feeding the first liquid phase into the first pipe group of the convection section of the cracking furnace, conducting preheating, and then conducting distilling to form a tower top fraction, a middle fraction and a tower bottom fraction; mixing the tower top fraction, the middle fraction and the first steam phase, feeding a formed mixture into a second pipe group of the convection section of the cracking furnace, conducting heating to a crossing temperature, and feeding the mixture into a radiation section for cracking to obtain cracking gas; and carrying out deep catalytic cracking on the tower bottom fraction to obtain deep catalytic cracking gas, and separating the deep catalytic cracking gas from the cracking gas to obtain the low-carbon olefin. The cracking furnace is matched with a vaporization treatment unit, a distillation unit and a deep catalytic cracking unit, so that the problems that a heavy cracking raw material cannot be fully gasified in a convection section and is easy to coke in a radiation section and a quenching part can be effectively solved.

Description

technical field [0001] The invention relates to the field of preparation of light olefins, in particular to a method and system for preparing light olefins from crude oil. Background technique [0002] Low-carbon olefins usually refer to the general term of unsaturated hydrocarbons with carbon four or less, mainly including ethylene, propylene, isobutylene, butadiene and other organic chemical raw materials with high economic value. With the development of my country's economy, the demand for these organic chemical raw materials is increasing year by year. Although the production scale of low-carbon olefins is also increasing year by year, it cannot meet the growing demand. [0003] For a long time, my country has been preparing low-carbon olefin products from naphtha. However, in recent years, with the massive exploitation of associated gas in oilfields in the Middle East and shale gas in the United States, these cheap oil and gas resources have been widely used as ethylen...

AI Technical Summary

Problems solved by technology

[0012] The purpose of the present invention is to provide a method and system for preparing low-carbon olefins from crude oil in order to overcome the problems of insufficient crude oil vaporization, easy coking in the cracking process, and low yield of low-carbon olefins in the prior art. It can improve the cracking efficiency of crude oil raw materials, prolong the operation period, reduce the coking phenomenon during cracking, and increase the yield of low-carbon olefins in the product at the same time

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