Method of hydrotreating feeds from renewable sources with indirect heating

摘要

The invention describes a method of treating feeds from renewable sources comprising:
a hydrotreatment stage a) comprising at least two catalytic zones in which the entry stream comprising said feed mixed with at least a part of a hydrotreated liquid effluent from stage b) is introduced into the first catalytic zone at a temperature comprised between 150 and 260° C., and the effluent from the first catalytic zone is then introduced, mixed with at least a part of a hydrotreated liquid effluent from stage b) and preheated, into the following catalytic zone or zones at a temperature comprised between 260 and 320° C.,a stage b) of separation of the effluent from the hydrotreatment stage a) permitting the separation of a gaseous effluent and of a hydrotreated liquid effluent of which at least a part is recycled upstream from each catalytic zone of stage a).

主权项

1. A method of treating feeds from renewable sources containing double bonds comprising:
Providing a hydrotreatment stage a) comprising at least a first catalytic zone serially flow-wise connected to a second catalytic zone; Forming an entry stream comprising a hydrogen rich gas, a first portion of a hydrotreated liquid effluent from a separation stage b), and a renewable feed comprises at least one selected from the group consisting of triglycerides, free fatty acids and esters; Introducing the entry stream to the first catalytic zone wherein a majority of the double bonds in the renewable feed are hydrogenated at a temperature of 180-210° C. to produce a hydrogenated effluent, and wherein the hydrogenated effluent has a temperature 50-60° C. higher than the entry stream; Preheating a second portion of the hydrotreated liquid effluent from separation stage b) to produce a preheated hydrotreated liquid effluent; Mixing the preheated hydrotreated liquid effluent with the hydrogenated effluent to produce a second entry stream; Introducing the second entry stream to a second catalytic zone at a temperature of 280-320° C. to deoxygenate-hydrodenitrogenate the hydrogenated effluent and to produce an effluent; Passing the effluent from the second catalytic zone to the separation stage b) to obtain a gaseous hydrogen-containing effluent and said hydrotreated liquid effluent, wherein at least a part of the hydrotreated liquid effluent is recycled as said first and said second portions with an overall recycle rate of greater than 0.5 and less than 3, and wherein the overall recycle rate is defined as the ratio of the mass flow rate of total recycled hydrotreated liquid effluent to the mass flow rate of fresh renewable feed.