Residual oil hydrotreatment method for prolonging device operating cycle

Abstract

The invention discloses a residual oil hydrotreatment method for prolonging a device operating cycle. The methods comprises the steps that under the hydro-conversion condition, the mixture of raw material residual oil and hydrogen passes through at least one reactor containing residual oil hydrotreatment catalysts; and at the steady-state inactivation stage of the residual oil catalysts, residual oil feed is switched into distillate containing a vulcanizer without shutdown and reversely passes through a catalyst bed layer in the hydrogenation reactor, and the distillate is switched to normal residual oil raw material after being reversely vulcanized and into an operation process. The method disclosed by the invention can play roles of delaying pressure drop rise and the appearance of hot spots, improving fluid distribution and prolonging a device operating cycle. The method disclosed by the invention can also be used in a restart process of an industrial device which is shut down emergently due to device failure, and can bring considerable economic benefits for a refinery.

Description

technical field [0001] The invention relates to a method for prolonging the operation cycle of a hydrogenation unit. The method is suitable for treating hydrogenation units with high content of impurities (solid particles, mechanical impurities, metals, colloids, asphaltenes), especially for fixed-bed residue hydrogenation reactors for processing inferior and heavy residues. Background technique [0002] As we all know, in recent years, as the world's crude oil has gradually become heavier and worse (increased sulfur, nitrogen, residual carbon, and metal content), and environmental protection regulations have become increasingly stringent, residual oil hydrotreating has become more and more important. At present, the hydrogenation processes for processing inferior and heavy residues mainly include fixed bed, ebullating bed, suspension bed, moving bed, etc. The fixed bed residue hydrotreating process is widely used because of its mature technology and simple operation. No ma...

AI Technical Summary

Problems solved by technology

However, even if the upflow reactor processes residual oil with high content of Fe, Ca, and particles for a long time, the pressure drop will increase due to the clogging of the upflow reactor. This phenomenon has occurred in industrial equipment

[0009] The industrialized method also has in addition: (1) increase the loading of protective agent, but this method has reduced the loading of main catalyst; The new catalyst continuously replaces the deactivated catalyst in the reactor to reduce the pressure drop and increase the metal content and carbon residue content of the raw oil, but the process is complex, the equipment investment is huge, and the operation is difficult; (3) HYVAHL of IFP in France The process adopts a switchable protective reactor in the hydrotreating of residual oil, and its advantage is that the heavy metal deposited on the catalyst in the protective reactor reaches 100% of the allowable amount of the catalyst, thereby reducing the generation of coke and metal deposition in the main reactor However, the investment in the process equipment is huge and the demand for the catalyst is large, which has not fundamentally solved the problem of metal deposition in the raw oil and the pressure drop of the reactor; (4) United Oil Company proposed the use of protective reactor Technology, add a protective reactor before the main reactor, fill the residual oil hydrodemetallization and hydrodesulfurization catalysts in the protective reactor, until the upper limit of the pressure drop of the protective reactor is allowed, and then throw away the protective reactor and take the bypass Until the whole unit replaces the catalyst to prolong the catalyst operation period

The above processes either require huge investment and are difficult to operate, or cannot fundamentally solve the pressure drop of the catalyst bed, and can only be operated at relatively low space velocities

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