催化裂化柴油加工转化过程的经济性分析

立足柴油组分的分子结构,通过分析各类柴油原料和其加氢产品的组成关系,研究柴油组分加氢精制过程中的芳烃饱和反应规律,以及不同加氢深度对催化裂化柴油(简称LCO)回炼时裂化转化结果的影响,从经济性角度探讨LCO的不同加工路线。结果表明:LCO加氢精制生产国Ⅵ标准柴油的过程中,芳烃加氢饱和反应的耗氢量占反应总耗氢量的50%左右;LCO因其密度大、多环芳烃含量高,作为国Ⅵ车用柴油调合组分时需要深度加氢饱和芳烃,因而耗氢成本巨大,经济性极差;采用LCO选择性加氢-催化裂化组合(LTAG)工艺时,LCO的加氢反应深度降低,耗氢成本大幅降低;可利用加氢转化制汽油、加氢转化制芳烃、加氢裂化混合掺炼、渣油加氢和催化裂化组合回炼等技术,实现富含芳烃的LCO资源的高效利用。

ECONOMIC ANALYSIS OF FCC DIESEL PROCESSING AND CONVERSION PROCESS

Based on the molecular structure of diesel components, the relationship of compositions of various diesel raw materials with hydrogenation products was analyzed; the dearomatization reaction rules in the hydrotreating process of diesel components and the impacts of different hydrogenation depths on LCO recycle conversion were discussed; the different processing routes of LCO from the economic point of view were compared. The results showed that the H2 consumption of hydrogenation saturation reaction accounted for about 50% of the total hydrogen consumption of the reaction in the hydrotreating process for producing China VI standard vehicle diesel fuel. Due to high density and high content of polycyclic aromatic hydrocarbons of raw material LCO, deep dearomatization is required for the production of China VI standard diesel fuel, resulting in large hydrogen comsumption and the poor economy. The combined process of selective hydrotreating and catalytic cracking (LTAG) can reduce the hydrogenation depth and greatly decrease the hydrogen cost. The technologies such as hydroconversion to produce gasoline, hydroconversion to produce aromatics, hydrocracking mixed blending feedstock, and combined process of residue hydrocracking and catalytic cracking reycling to realize efficient utilization of LCO resources rich in aromatics.