Process for the treatment of refinery purge streams

Patent metadata

Field	Value
Publication number	US-10865347-B2
Application number	US-201615781503-A
Country	US
Kind code	B2
Filing date	Dec 21, 2016
Priority date	Dec 22, 2015
Publication date	Dec 15, 2020
Grant date	Dec 15, 2020

Abstract

The present invention relates to a process for the treatment of refinery purge streams, containing a hydrocarbon component in slurry phase having a boiling point higher than or equal to 140° C., characterized by the presence of quantities of asphaltenes higher than or equal to 5% by weight and characterized by the presence of a solid content higher than or equal to 5% by weight. The process provides that said purge be mixed with a suitable fluxing agent according to appropriate ratios and under certain conditions, forming a suspension with a content higher than or equal to 10% by weight of compounds having a boiling point TbP lower than or equal to 350° C. After mixing, the suspension is sent to a liquid/solid separation step which operates under suitable conditions, separating a solid phase containing a residual organic component and a solid component, called cake, and a liquid phase containing residual solids. The solid phase obtained is cooled to below 60° C., including the upper extreme, forming a granular solid which is stored and maintained at a temperature lower than or equal to 60° C.

First claim

The invention claimed is:

1. A process for the treatment of refinery purge streams, the process comprising:
a) withdrawing a refinery purge stream comprising a hydrocarbon component in slurry phase having a boiling point higher than or equal to 140° C., characterized by the presence of quantities of asphaltenes higher than or equal to 5% by weight and characterized by the presence of solid contents greater than or equal to 5% by weight;
b) mixing said purge, at a temperature higher than or equal to 100° C., with a fluxing agent, having a total content of aromatic compounds ranging from 50% to 70% by weight, and an initial boiling point equal to or higher than the temperature at which the mixing is carried out, wherein the fluxing agent is a mixture of Vacuum Gas Oil (VGO) and High Vacuum Gas Oil, so as to form a suspension with a content higher than or equal to 10% by weight of compounds having a boiling point T bp lower than or equal to 350° C.;
c) sending said suspension to a liquid-solid separation step, which operates at a temperature higher than or equal to 100° C., separating a solid phase comprising a residual organic component and a solid component, or cake, and a liquid phase comprising residual solids;
d) cooling the solid phase thus obtained to 60° C. or less, and storing it, maintaining it at a temperature lower than or equal to 60° C.;
wherein a weight ratio between purge and fluxing agent ranges from 1:0.5 to 1:4; and an average residence time of the mixture during the mixing and before the liquid-solid separation is lower than or equal to 12 hours.

2. The process according to claim 1 , wherein the solids contained in the purge stream comprise carbonaceous residues, metallic compounds and catalysts in the form of particles having a D50 lower than or equal to 1 mm.

3. The process according to claim 1 , wherein the average residence time of the mixture during the mixing is lower than or equal to 3 hours.

4. The process according to claim 1 , wherein the metallic compounds contained in the purge are either Ni sulfides, or V sulfides, or Fe sulfides or mixtures thereof.

5. The process according to claim 1 , wherein the mixing temperature ranges from 100° C. to 200° C.

6. The process according to claim 1 , wherein the solid-liquid separation takes place at temperatures ranging from 100 to 200° C.

7. The process according to claim 1 , wherein the suspension has a content ranging from 15% to 50% of compounds having a boiling point lower than or equal to 350° C.

8. The process according to claim 1 , wherein the weight ratio between purge and fluxing agent ranges from 1:1 to 1:2.

Assignees

• Eni Spa

Inventors

• Bartolini Andrea

Classifications

• C10G21/12

  Organic compounds only · CPC title

• C10G31/06 Primary

  by heating, cooling, or pressure treatment · CPC title

• B01J23/94

  of catalysts comprising metals, oxides or hydroxides of the iron group metals or copper · CPC title

• C10G21/14 Primary

  Hydrocarbons · CPC title

• C10G31/10 Primary

  with the aid of centrifugal force · CPC title