Hydrocracking method for producing lube base oil

Abstract

The invention discloses a hydrocracking method for producing lube base oil. The method comprises the steps of: firstly performing hydrocracking on raw oil, feeding oil generated after the hydrocracking into an atmospheric tower for fractionation, feeding obtained atmospheric tail oil into a vacuum tower for fractionation to obtain light tail oil, intermediate tail oil and heavy tail oil, and mixing the light tail oil and the heavy tail oil to obtain the lube base oil. In the hydrocracking method disclosed by the invention, by means of flexible segmentation treatment to the hydrocracked tail oil, a tail oil component with high condensation point is separated from the tail oil on the premise of not influencing the quality of other products, so that the lube base oil with low condensation point is obtained. According to the hydrocracking method, by means of only performing slighter reformation on the hydrocracking tower, the lube base oil with higher added value can be produced while light fuel oil is obtained, meanwhile, a downstream tail oil isodewaxing device can be omitted. The hydrocracking method has the advantages of simplified process flow, low operation cost, low material consumption, low energy consumption, low manpower consumption, low total investment and the like.

Description

technical field [0001] The invention relates to a hydrocracking method, in particular to a method for producing high-quality lubricating oil base oil by utilizing the hydrocracking process. Background technique [0002] In the international market, 70% to 99% of finished lubricants are base oils. Conventional solvent refining technology for lubricating base oil production has been used industrially for more than 50 years. Although there have been some technical improvements in recent years, the main reasons are energy saving and production cost reduction, and only low-quality lubricating oil can be produced, with little improvement in product properties. With the development of the modern automobile industry, the quality requirements for automotive lubricating oils are getting higher and higher, and correspondingly higher requirements are put forward for base oils. They have higher performance in terms of low-temperature fluidity, viscosity and oxidation stability. Requirem...

AI Technical Summary

Problems solved by technology

The content of saturated hydrocarbons in the tail oil is very high, the content of aromatics is very low, and the content of sulfur and nitrogen is very low, so it is a good raw material for producing high-quality lubricating oil base oil, but the content of paraffins is high, which is difficult to meet the requirements of lubricating oil. Therefore, the use of hydrocracking tail oil through hydroisomerization process can produce light lubricating oil base oil to meet the needs of the lubricating oil market

[0004] At present, the main methods for preparing high-quality lubricating oil base oils from hydrocracking tail oils are: using hydrocracking-tail oil isomerization dewaxing combined process to prepare lubricating oil base oils, which includes hydrocracking and tail oil Two units of shape-selective isomerization, the tail oil of the hydrocracking unit is directly supplied to the shape-selective isomerization unit as raw material, and high-quality lubricating oil base oil is produced after shape-selective isomerization; although this method can produce lubricating oil, However, it is necessary to increase the tail oil shape-selective isomerization device, which increases the investment of the enterprise and increases the consumption of manpower and material resources.

Using a hydrocracking catalyst with isomerism depressing characteristics, the tail oil can be directly produced as a lubricating base oil under the condition of a relatively high conversion rate. Although this method can directly produce the tail oil as a lubricating oil base oil, there are limitations on the catalyst, The requirements for process conditions are relatively high. For industrial production, it is difficult to ensure long-term stable operation.

[0005] CN93110073.9 discloses a method for producing lubricating base oil by hydrodewaxing. Although high-quality lubricating oil with low freezing point can be produced, a shape-selective catalyst is required for one-stage hydrodewaxing, which consumes a lot of manpower and material resources.

[0006] CN98119809.0 introduces a method for preparing lubricating base oil. Under the condition of non-hydrogenation, a molecular sieve catalyst is selected to carry out shape-selective cracking of hydrocracking tail oil, so that hydrocracking tail oil is selectively cracked, thereby reducing the amount of base oil Freezing point, but shape-selective cracking is also required, the investment is large, and the yield of base oil is low

Images