Inferior diesel oil hydro-upgrading and hydro-refining combined process

Abstract

The invention discloses a combination process of hydrogenation upgrading and hydrogenation refining of low-quality diesel oil. The diesel raw material is fractionated to obtain light and heavy fractions, and the light fraction is extracted by aromatics to obtain light aromatic fractions and light non-aromatic fractions; the heavy fraction enters the hydrotreating reactor, and the material after passing through the first hydrotreating catalyst bed is divided into two One stream of material enters the separator, and the obtained liquid is drawn out of the hydrofinishing reactor and the light aromatic fraction enters the supplementary hydrofinishing reactor for supplementary hydrogenation reaction; the other stream of material is mixed with the light non-aromatic fraction and continues to flow downward through the first The second hydrorefining catalyst bed, the hydrorefining stream continues to enter the hydrorefining reactor, and the hydrorefining reaction material and the supplementary hydrorefining reaction material are subjected to gas-liquid separation and fractionation respectively to obtain high-quality diesel products and high-quality FCC feedstocks. material. The invention provides a combined hydrogenation process for simultaneously producing two or more diesel oil fractions with different purposes on a set of hydrogenation process devices.

Description

technical field [0001] The invention belongs to the field of petroleum refining, and in particular relates to a flexible diesel hydrogenation upgrading and hydrofining combined process for flexibly producing high-quality diesel products and high-quality FCC raw materials by using low-quality diesel oil as raw material oil. Background technique [0002] The increasingly stringent environmental protection regulations require higher and higher quality diesel products, mainly due to the increasing restrictions on sulfur content, cetane number, density and polycyclic aromatic hydrocarbon content. Low-quality diesel hydro-upgrading technology can greatly reduce the sulfur content and aromatics content of diesel products, reduce density and increase cetane number. Fluid Catalytic Cracking (FCC) is one of the important means of lightening heavy oil, but with the deterioration and heavyness of catalytic cracking raw materials, its operating conditions are becoming more and more strin...

AI Technical Summary

Problems solved by technology

Distillate fraction hydroisomerization depreciation technologies, such as CN1718683A and CN1712499A, etc., use hydrofinishing catalysts and hydroisomerization depreciation catalysts containing zeolite β, and adopt a series of processes to produce diesel products, but under the same hydro-upgrading conditions The cetane number is lower than that of hydrogenated diesel oil, and the process conditions for the same low-condensation-point diesel products are harsher than those of hydrogenated decondensation process

CN101875856A, CN102465035A and CN106701189A, CN106701190A disclose a process technology for blending LCO in wax oil hydrotreating or residual oil hydrotreating process, the main purpose is to produce high-quality catalytic cracking raw materials, or let LCO be used in wax oil hydrotreating unit Coupling technology with circulation between catalytic cracking units realizes clean production of catalytic cracking units. However, since wax oil and LCO are directly hydrogenated after mixing, the depth of hydrogenation of LCO cannot be effectively controlled, and only mixed hydrogenation products (catalytic cracking raw materials ) sulfur content or nitrogen content as the control target, which is not conducive to the effective control of LCO production of high-quality gasoline

The above process technology is not combined with the aromatics extraction technology, and there is usually only one type of diesel product produced, and the product flexibility is poor

Images