Hydromethanation of a carbonaceous feedstock with nickel recovery

• US 8,648,121 B2
• Filed: 02/22/2012
• Issued: 02/11/2014
• Est. Priority Date: 02/23/2011
• Status: Active Grant

• Current Assignee: Sure Champion Investments Limited
• Original Assignee: GreatPoint Energy, Inc.
• Inventors: Rappas, Alkis S., Spitz, Robert A.
• Primary Examiner(s): Richter, Johann R
• Assistant Examiner(s): Adzamli, Kofi
• Application Number:
  US13/402,022
• Publication Number:
  US 20120213680A1
• Time in Patent Office: 720 Days
• Field of Search: 518700-705
• US Class Current: 518/702
• CPC Class Codes: C10J 2300/0903 Feed preparation
• CPC Class Codes: C10J 2300/0943 Coke
• CPC Class Codes: C10J 2300/0976 as steam
• CPC Class Codes: C10J 2300/0986 Catalysts
• CPC Class Codes: C10J 2300/1628 Ash post-treatment
• CPC Class Codes: C10J 2300/1662 to methane
• CPC Class Codes: C10J 2300/1807 Recycle loops, e.g. gas, solids, heating medium, water
• CPC Class Codes: C10J 2300/1823 for synthesis gas
• CPC Class Codes: C10J 3/00 Production of combustible gases containing carbon monoxide from solid carbonaceous fuels destructive distillation processes C10B
• CPC Class Codes: C22B 23/04 by wet processes recovery or separation of nickel or cobalt using organic agents C22B3/00
• CPC Class Codes: C22B 23/0446 with an ammoniacal liquor or with a hydroxide of an alkali or alkaline-earth metal
• CPC Class Codes: C22B 7/008 by an alkaline or ammoniacal leaching
• CPC Class Codes: Y02P 10/20 Recycling

Abstract

The present invention relates to processes for hydromethanating a nickel-containing (and optionally vanadium-containing) carbonaceous feedstock while recovering at least a portion of the nickel content (and optionally vanadium content) originally present in the carbonaceous feedstock.

Claims

1. A process for generating a methane-enriched raw product gas stream and a nickel product stream from a non-gaseous nickel-containing carbonaceous material, the process comprising the steps of:

(a) preparing a catalyzed carbonaceous feedstock from the nickel-containing carbonaceous material and an alkali metal hydromethanation catalyst, wherein the alkali metal hydromethanation catalyst comprises a recycle catalyst and a makeup catalyst;

(b) introducing the catalyzed carbonaceous feedstock into a hydromethanation reactor;

(c) reacting the catalyzed carbonaceous feedstock in the hydromethanation reactor in the presence of carbon monoxide, hydrogen and steam to produce a methane-enriched raw product gas and a solid by-product char;

(d) withdrawing a stream of the methane-enriched raw product gas from the hydromethanation reactor as the methane-enriched raw product gas stream, wherein the methane-enriched raw product gas stream comprises methane, carbon monoxide, hydrogen, carbon dioxide, hydrogen sulfide, steam and heat energy;

(e) withdrawing a stream of the solid by-product char from the hydromethanation reactor, wherein the withdrawn solid by-product char comprises carbon and an inorganic ash containing an alkali metal content and a nickel content;

(f) treating the withdrawn solid by-product char to generate (1) an alkali metal-depleted char stream comprising a substantial portion of the nickel content, and (2) an aqueous alkali metal-enriched stream comprising one or more water-soluble alkali metal compounds, wherein the aqueous alkali metal-enriched stream comprises at least a predominant portion of the alkali metal content of the withdrawn solid by-product char;

(g) recycling at least a portion of the aqueous alkali-metal enriched stream for use as the recycle catalyst;

(h) treating the alkali metal-depleted char stream to generate a nickel-enriched stream and a nickel-depleted char stream, wherein the nickel-enriched stream comprises at least a predominant portion of the nickel content;

(i) recovering at least a predominant portion of the nickel from the nickel-enriched stream in step (h) as the nickel product stream.

2. The process of claim 1, wherein the char by-product withdrawn from the hydromethanation is quenched by contacting the char by-product with an aqueous quench stream.

3. The process of claim 2, wherein a quenched char slurry is generated by the quenching step, which is contacted with a stream of carbon dioxide, followed by a stream of an oxygen-containing gas, followed by solid/liquid separation, to generate the alkali metal-depleted char stream and the aqueous alkali metal-enriched stream.

4. The process of claim 2, wherein a quenched char slurry is generated by the quenching step, which is contacted with a stream of an oxygen-containing gas, optionally followed by a stream of carbon dioxide with pressure let down, followed by solid/liquid separation, to generate the alkali metal-depleted char stream and the aqueous alkali metal-enriched stream.

5. The process of claim 1, wherein the alkali metal-depleted char stream is treated by acid extraction to generate the nickel-enriched stream and the nickel-depleted char.

6. The process of claim 5, wherein the nickel-enriched stream is treated by electrodeposition to generate the nickel product stream.

7. The process of claim 1, wherein the alkali metal-depleted char stream is treated by ammonia extraction to generate the nickel-enriched stream and the nickel-depleted char.

8. The process of claim 7, wherein the nickel-enriched stream is treated by steam stripping to generate the nickel product stream.

9. The process of claim 1, wherein the nickel-containing carbonaceous material is also a vanadium-containing carbonaceous material, and wherein the methane-enriched raw product gas stream, the nickel product stream and a vanadium product stream are produced by a process comprising the steps of:

(A) preparing the catalyzed carbonaceous feedstock from the vanadium and nickel-containing carbonaceous material and the alkali metal hydromethanation catalyst;

(B) introducing the catalyzed carbonaceous feedstock into the hydromethanation reactor;

(C) reacting the catalyzed carbonaceous feedstock in the hydromethanation reactor in the presence of carbon monoxide, hydrogen and steam to produce the methane-enriched raw product gas and the solid by-product char;

(D) withdrawing the stream of the methane-enriched raw product gas from the hydromethanation reactor as the methane-enriched raw product gas stream;

(E) withdrawing the stream of the solid by-product char from the hydromethanation reactor, wherein the withdrawn solid by-product char comprises carbon and an inorganic ash containing the alkali metal content, the nickel content and a vanadium content;

(F) treating the withdrawn solid by-product char to generate (1) an alkali metal and vanadium-depleted char stream, and (2) an aqueous alkali metal and vanadium-enriched stream comprising one or more water-soluble alkali metal compounds and one or more water-soluble vanadium compounds, wherein the aqueous alkali metal and vanadium-enriched stream comprises at least a predominant portion of the alkali metal content and at least a predominant portion of the vanadium content of the withdrawn solid by-product char, and the alkali metal and vanadium-depleted char steam comprises a predominant portion of the nickel content of the withdrawn solid by-product char;

(G) separating the aqueous alkali metal and vanadium-enriched stream into a bleed stream and a catalyst recycle stream, wherein the bleed stream comprises a bleed vanadium content;

(H) recycling at least a portion of the catalyst recycle stream for use as the recycle catalyst;

(I) treating the bleed stream to generate a vanadium-enriched stream and a vanadium-depleted stream, wherein the vanadium-enriched stream comprises at least a predominant portion of the bleed vanadium content;

(J) contacting the vanadium-enriched stream with an ammonia stream to generate an ammonium vanadate;

(K) recovering at least a predominant portion of the ammonium vanadate generated in step (J) as the vanadium product stream;

(L) treating the alkali metal and vanadium-depleted char stream to generate the nickel-enriched stream and the nickel-depleted char stream; and

(M) recovering at least a predominant portion of the nickel from the nickel-enriched stream in step (L) as the nickel product stream.

10. The process of claim 9, wherein the char by-product withdrawn from the hydromethanation is quenched by contacting the char by-product with an aqueous quench stream.

11. The process of claim 10, wherein a quenched char slurry is generated by the quenching step, which is contacted with a stream of carbon dioxide, followed by a stream of an oxygen-containing gas, followed by solid/liquid separation, to generate the alkali metal and vanadium-depleted char stream and the aqueous alkali metal and vanadium-enriched stream.

12. The process of claim 10, wherein a quenched char slurry is generated by the quenching step, which is contacted with a stream of an oxygen-containing gas, optionally followed by a stream of carbon dioxide with pressure let down, followed by solid/liquid separation, to generate the alkali metal and vanadium-depleted char stream and the aqueous alkali metal and vanadium-enriched stream.

13. The process of claim 9, wherein the catalyst recycle stream split from the aqueous alkali metal and vanadium-enriched stream comprises from about 75 wt % to about 95 wt % of the aqueous alkali metal and vanadium-enriched stream.

14. The process of claim 9, wherein the bleed stream is subject to a solvent extraction step to generate the vanadium-enriched stream and the vanadium-depleted stream.

15. The process of claim 9, wherein the vanadium-depleted stream is contacted with carbon dioxide to recover alkali metal content from the vanadium-depleted stream.

16. The process of claim 15, wherein at least a part of the recovered alkali metal content is used as recycle catalyst.

17. The process of claim 9, wherein the alkali metal and vanadium-depleted char stream is treated by acid extraction to generate the nickel-enriched stream and the nickel-depleted char.

18. The process of claim 17, wherein the nickel-enriched stream is treated by electrodeposition to generate the nickel product stream.

19. The process of claim 9, wherein the alkali metal and vanadium-depleted char stream is treated by ammonia extraction to generate the nickel-enriched stream and the nickel-depleted char.

20. The process of claim 19, wherein the nickel-enriched stream is treated by steam stripping to generate the nickel product stream.

21. The process of claim 1, wherein the carbonaceous material is a petcoke.

22. The process of claim 1, wherein the alkali metal hydromethanation catalyst is a potassium hydromethanation catalyst.