A hydrogenation method for increasing the cetane number of inferior diesel oil

Abstract

The invention discloses a hydrogenation method for enhancing cetane number of inferior diesel. The method comprises the following steps: (1) sufficiently mixing the inferior diesel raw material and a powdery hydrofining catalyst in a mixer to obtain a catalyst-raw oil feed mixture; (2) adding the feed mixture and hydrogen into an ebullated bed reactor from the reactor bottom filled with a mixture of a hydrodefreezing catalyst and a hydrogenation modification catalyst, and carrying out hydrogenation reaction; (3) discharging the reaction stream containing the powdery hydrofining catalyst out of the top of the ebullated bed reactor into a stable reactor, and carrying out supplementary hydrofining; and (4) carrying out solid-liquid separation on the material obtained in the step (3), and sending the liquid phase into a fractionating system to obtain the high-quality low-pour-point low-sulfur high-cetane-number diesel product. The method reasonably combines the temperature drop in the hydrodefreezing process and the temperature rise in the hydrogenation modification process, thereby lowering the low-pour-point high-cetane-number diesel, lowering the hot-spot temperature of the device and prolonging the operating cycle on the premise of ensuring the high diesel yield.

Description

technical field [0001] The invention relates to a method for hydrogenation and upgrading of low-quality diesel oil, in particular to a production method for producing high-quality high-cetane number diesel oil through an ebullating bed reactor. Background technique [0002] Diesel, as a fuel for compression ignition engines, plays an irreplaceable role as a non-renewable resource in modern production and life, and can be used as vehicles, tanks, airplanes, tractors, railway vehicles and other vehicles or other machinery Fuel can also be used for power generation, heating, etc. Depending on the industry and environment in which it is used, the quality requirements of users for diesel products are also very different. For people living in alpine regions or in winter, the demand for low-condensing-point diesel has always been high. The traditional choice The cracking process can process waxy heavy diesel fractions, and the pour point depressing range can reach 20-50°C. While o...

AI Technical Summary

Problems solved by technology

In this method, the temperature drop in the bed of the hydrodepreciation catalyst is relatively large, and the yield of the diesel fraction and the improvement of the depreciation effect are limited to a certain extent, which reduces the service life of the hydrodecondensation catalyst.

[0006] CN102051232A introduces a method for diesel hydrotreating decondensation, which has the characteristics of good diesel decondensation effect and high yield of diesel fractions by adjusting the properties of the catalyst. Combined process, conflict between pour point depressing effect and diesel fraction yield still exists

[0008] The reaction temperature at the outlet of each bed layer is still relatively high, and the cycle is limited to a certain extent

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