Combined technology for heavy oil processing

Abstract

The invention provides a combined technology for heavy oil processing. The combined technology at least comprises the steps of performing solvent de-asphalting process on a heavy oil raw material and performing thermal cracking process on a de-oiling asphalt phase and a dispersing agent in a thermal cracking reactor after the de-oiling asphalt phase and the dispersing agent are mixed, wherein the de-asphalted oil and thermal cracked oil separated from a thermal cracking reaction product are mixed to obtain a modified oil; and a solvent separated from the thermal cracking reaction product and heavy wax oil are respectively returned to the solvent de-asphalting process to be used circularly and serve as a mixed feeding material to remove the asphaltene. For the implementation of the invention, the combined technology for the heavy oil processing, disclosed by the invention, has the advantages of solving the problem that the asphalt with a high softening point is difficult to separate from the solvent in the transportation and solvent de-asphalting process of the heavy oil, enabling extractable oil component in the heavy oil to avoid a heat treatment, being good for guaranteeing stability of products and improving yield of the modified oil, greatly improving API (American Petroleum Institute) degree, obviously reducing residual carbon value, C7 asphaltene and metal contents, achieving an asphaltene removal rate of higher than 96% and the metal nickel as well as vanadium removal rate of 80%-90%, and being good for producing hydrogenised modified oil with obviously improved quality.

Description

Technical field [0001] The invention relates to a combined process for deep processing of heavy oil, in particular to the process of pre-fractionation, heavy fraction deasphalting and thermal cracking of heavy crude oil, extra-heavy crude oil and oil sand pitch, as well as fixed-bed hydrotreating to produce high The combined process of quality modified oil belongs to the field of heavy oil processing. Background technique [0002] Heavy oil means that the API degree is lower than 20 (the density is higher than 0.932g / cm at 20℃) 3 ) Generally includes heavy crude oil, oil sands bitumen and residual oil. Because of the high density, high viscosity, and high freezing point of heavy crude oil and oil sands, they lose their fluidity at ambient temperature or higher and cannot be transported and processed like conventional crude oil, especially those with an API degree lower than 10 Heavy oil and oil sand bitumen need to be lightened into synthetic oil before being transported to refi...

AI Technical Summary

Problems solved by technology

However, in the heavy oil lightening processing technology that has been used or disclosed at present, no matter what kind of combination process is used, it is necessary for the solvent separation in the deoiled asphalt, that is, the deoiled asphalt must be separated from the solvent and then combined with the deoiled asphalt. Into the follow-up combination process, so the two problems of separation of high softening point asphalt from solvent and transportation of high softening point asphalt in the process of solvent deasphalting have not been solved; on the other hand, the current heavy oil processing technology, in order to reduce Difficulty, to a certain extent, can only be at the cost of sacrificing the yield of deasphalted oil, so the amount of deoiled asphalt must be increased, and the oil content in asphalt is higher, which actually increases the amount of coke after thermal reaction of asphalt, that is , it is difficult to reduce the yield of coke and gas; on the other hand, in order to reduce the difficulty of separation of high softening point asphalt and solvent and the difficulty of transportation of high softening point asphalt, the oil in deoiled asphalt is relatively large. During thermal cracking treatment, The condensation reaction of some oil molecules will inevitably lead to an increase in the amount of coke in the thermal reaction, which will affect the liquid yield and the stability of the modified product

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