Sulfur-containing light hydrocarbon remilling and purifying process

Abstract

The invention discloses a sulfur-containing light hydrocarbon remilling and purifying process, which has the technical scheme that the sulfur-containing light hydrocarbon which is returned from a reforming pre-hydrogenation unit to a stabilization tower of a light hydrocarbon recovery system is sent to a rich gas liquid separation tank, is mixed with catalytic rich gas from a catalytic cracking device and / or lean gas returned from a desorption tower, and is subjected to gas-liquid separation; and carrying out gas absorption, desorption, desulfurization and mercaptan removal on the separated gas and condensed oil to respectively obtain dry gas, liquefied gas and light gasoline. By adopting the system and the method, the processing load of the reforming device can be improved on the basis of reducing the load of the pre-hydrogenation unit, so that the loads of the devices of the whole system are better matched, the energy consumption is reduced, the yields of high-octane gasoline, light aromatic hydrocarbon and hydrogen are improved, the sulfur-containing light hydrocarbon is effectively utilized, and high-value liquefied gas products such as propane and propylene are produced.

Description

technical field [0001] The invention relates to the field of oil refining, in particular to a process for refining and purifying sulfur-containing light hydrocarbons. Background technique [0002] The process of the traditional refining system generally includes atmospheric and vacuum units, catalytic cracking units, delayed coking, catalytic reforming units, hydrofining, hydrocracking units, etc. Catalytic reforming refers to the production of high-octane The important refining process of alkane gasoline, light aromatics and by-product hydrogen, because the reforming reaction has high requirements on the raw materials, it generally needs to pre-hydrotreat the raw materials. Sulfur-containing light hydrocarbons are a mixture of non-condensable gas, crude liquefied gas, and light gasoline produced by the pre-hydrogenation unit of the catalytic reforming unit of the refinery. It is the light hydrocarbon recovery system (including stabilizing tower and desulfurization tower) a...

AI Technical Summary

Problems solved by technology

The naphtha pipeline from the atmospheric and vacuum unit in some refineries is connected to the light hydrocarbon recovery system, and the naphtha pipeline from the light hydrocarbon recovery system is connected to the reforming pre-hydrogenation unit, and the sulfur-containing light hydrocarbons from the pre-hydrogenation unit are Then return to the light hydrocarbon recovery system through the pipeline connection; the main purpose is to separate the non-condensable gas and liquefied gas in the straight-run naphtha and hydrogenated light naphtha, that is, the sulfur-containing light hydrocarbons, so as to obtain distillate with better quality. However, in the actual production process, the light hydrocarbon recovery system is difficult to completely separate the non-condensable gas and liquefied gas in the light naphtha, resulting in non-condensable gas and liquefied gas Ineffective components such as naphtha are mixed into the pre-hydrogenation unit of the catalytic reforming unit, and the sulfur-containing light hydrocarbons fractionated out are sent back to the stabilization tower of the light hydrocarbon recovery system, occupying part of the raw material processing capacity, forming a vicious circle

Taking a certain unit as an example, the processing scale of the reforming unit is 400,000 tons per year, the total feed rate of the reforming pre-hydrogenation unit is designed to be 54t / h (100% load), and the sulfur-containing light hydrocarbon is 0t / h. After the head oil, the reforming feed is 47.6t / h (load 100%); in the actual production process, the total feed is 62t / h, while the production of sulfur-containing light hydrocarbons is 5t / h, resulting in the pre-hydrogenation unit exceeding Load operation (110%), but after removing the top oil, the actual reaction load of the reforming unit cannot reach 100% (46.8t / h), which seriously restricts the production of high-octane gasoline, light aromatics and hydrogen

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