Method for modification by coupling hydrodesulfurization of FCC (Fluid Catalytic Cracking) gasoline and aromatization of liquefied petroleum gas

Abstract

The invention provides a method for modification by coupling hydrodesulfurization of FCC (Fluid Catalytic Cracking) gasoline and aromatization of liquefied petroleum gas. All-fraction FCC gasoline is sequentially subjected to selective hydrogenation and preliminary desulfurization treatment to obtain HCN (Hydrogen Cyanide) heavy-component gasoline by fractionation, and the obtained HCN heavy-component gasoline is then subjected to hydrodesulfurization treatment; and the HCN heavy-component gasoline obtained from the hydrodesulfurization treatment and liquefied petroleum gas are co-fed into a fixed bed multi-stage aromatization reactor to recover/improve the octane number of a gasoline product through the processes of polymerization, pyrolysis, aromatization, hydrogen transfer and the like of olefin. The method is applied to the production process of ultra-low sulfur clean gasoline meeting national IV gasoline standard, and especially the ultra-low sulfur clean gasoline meeting national V gasoline standard. As a gradual desulfurization process is adopted, the operation conditions of all the units are mild, the desulfurization process is coupled with a liquefied petroleum gas aromatization process, and therefore the method has the characteristics that the gasoline desulfurization efficiency is high, the octane number loss of a product does not lose and is even increased, the gasoline yield is increased and the reaction process is flexible.

Description

technical field [0001] The invention belongs to the technical field of clean vehicle fuel production, and in particular relates to a method for coupled upgrading of FCC gasoline hydrodesulfurization-liquefied gas aromatization. Background technique [0002] With the rapid development of my country's economy, the demand for oil resources is increasing. In 2010, my country's oil demand reached 455 million tons, of which more than 250 million tons of crude oil and refined oil were imported. The shortage of oil resources has become a bottleneck restricting the sustainable development of my country's economy and society. In the next few decades, the most in short supply of petroleum downstream products will be vehicle transportation fuels, mainly gasoline and diesel (Contemporary Petroleum and Petrochemical, Vol. 17, No. 11, 2009, Countermeasures for the sustainable development of my country's oil refining and petrochemical industries) . [0003] With the increasing attention to...

AI Technical Summary

Problems solved by technology

Olefins in FCC gasoline contribute a lot to the octane number of gasoline. In order to meet China IV and Euro V standards for clean gasoline, further hydrodesulfurization is required to reduce the content of sulfur and olefins in gasoline. The biggest problem in this process is the deep desulfurization process. Olefins are easily hydrogenated and saturated into alkanes, resulting in a significant drop in the octane number of gasoline

In particular, the high ratio of catalytic cracking and slag in my country's local refineries leads to high sulfur and olefin content in catalytic gasoline, making it difficult to clean gasoline

Traditional hydrorefining technology is difficult to meet its cleaning upgrade requirements

[0004] In recent years, some catalytic gasoline selective hydrodesulfurization technologies have been developed at home and abroad, such as Prime-G, Prime-GW and related gasoline hydrodesulfurization technologies of domestic scientific research institutes. In the application of gasoline hydrofinishing, there are disadvantages of rapid catalyst deactivation, high olefin saturation rate, and large loss of gasoline octane number

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