Method for producing the clean diean diesel oil with low sulfur and low arene

Abstract

A process for preparing low-sulfur low-arylhydrocarbon clean diesel oil includes such steps as hydrorefining/hydrocracking raw hydrocarbon to obtain intermediate fraction oil, catalytic stripping to separate light fraction from heavy fraction, hydrorefining the light fraction to remove residual S and impurities, and catalytic stripping of heavy fraction for removing sulfure and arylhydrocarbon to obtain final product. Its advantage is cyclic use of two reactino segments for low cost.

Description

1. Technical field [0001] The invention relates to a method for processing hydrocarbon raw materials to produce low-sulfur and low-aromatic clean fuels (especially clean diesel oil), more specifically, it is a hydrogenation process combination technology for converting hydrocarbon raw materials into low-sulfur and low-aromatic fuels . 2. Background technology [0002] As we all know, with the rapid development of the transportation industry and the automobile industry worldwide, the demand for diesel for vehicles increases rapidly. At the same time, the control of automobile exhaust emissions in the new environmental protection regulations has higher and higher requirements on the quality of diesel oil. In particular, the "World Fuel Specifications" published in 1997 has strict requirements on the sulfur content, cetane number, and aromatic content of diesel oil (including polycyclic aromatic hydrocarbon content) and density, etc. have put forward more stringent requirement...

AI Technical Summary

Problems solved by technology

Although this technological process can greatly save the land occupation and investment of the device, there are still two disadvantages: one is that the adjustment range of the reaction temperature of the dearomatization catalyst bed in the lower part of the reactor is very narrow, and since there is no heating furnace, the dearomatization reaction bed The reaction temperature of the desulfurization bed must be lower than the reaction temperature of the desulfurization bed, but the reaction temperature of the dearomatization reaction bed cannot be much lower than the reaction temperature of the desulfurization bed, otherwise, a large amount of cold hydrogen needs to be used, thereby increasing the operating cost of the device. At the same time, the process requires that the deactivation rates of the desulfurization catalyst and the dearomatization catalyst are basically synchronized; secondly, the reaction gas is drawn from the middle of the reactor, and at the same time, it is necessary to ensure that no liquid is carried as much as possible, the design will be very complicated

Due to the co-current contact between the material and hydrogen on the surface of the catalyst, the mixing effect cannot be very good, and the reaction will not be very sufficient. In addition, a gas-liquid separation / circulation system must be installed, which increases equipment investment.

Images