Method for the recovery of acids from hydrometallurgy process solutions
A method for the recovery of acids and other materials from hydrometallurgic process solutions comprising processing said solutions utilizing a simulated moving bed chromatographic method to produce at least two product streams.
1. A method for recovering acid and/or metals from an acid and metal salt solution, the method comprising:
feeding a feed solution comprising an acid and metal salt solution to a simulated moving bed in a system comprising one or more columns or beds containing a resin;
feeding an aqueous eluent to the simulated moving bed; and
removing at least a first product stream and a second product stream from the simulated moving bed, wherein the first product stream comprises a higher concentration of the acid than the second product stream.
2. The method according to claim 1 , wherein the feed solution comprises one or more acids selected from the group consisting of sulfuric acid, hydrochloric acid, nitric acid, acetic acid and phosphoric acid.
3. The method according to claim 1 , wherein the simulated moving bed (SMB) is selected from the group consisting of continuous SMB, semi-continuous SMB, time variable SMB, sequential SMB, and pulsed SMB.
4. The method according to claim 1 , wherein feeding a feed solution comprising an acid and metal salt solution to a simulated moving bed and feeding an aqueous eluent to the simulated moving bed comprises cyclically introducing the feed solution and the aqueous eluent to the simulated moving bed.
5. The method according to claim 4 , wherein the eluent comprises less than 5% dissolved components.
6. The method according to claim 1 , wherein the feed solution is filtered prior to feeding to the simulated moving bed.
7. The method according to claim 1 , comprising utilizing an anion resin in the simulated moving bed.
8. The method according to claim 7 , wherein the anion resin is a weak base anion resin.
9. The method according to claim 7 , wherein the anion resin is a strong base anion resin.
10. The method according to claim 9 , wherein the anion resin is a type I anion resin.
11. The method according to claim 9 , wherein the anion resin is a type II anion resin.
12. The method according to claim 1 , wherein at least one of the product streams is subjected to further processing in a separate system by one or more methods selected from the group consisting of chromatography, filtration, membrane treatment, evaporation, distillation, drying, gas absorption, solvent extraction, press extraction, adsorption, ion exchange and centrifugation.
13. The method according to claim 1 , further comprising recycling at least one of the at least a first product stream and a second product stream for re-use in a process producing the feed solution comprising an acid and metal solution.
14. The method according to claim 1 , further comprising:
monitoring conductivity of the metal salts in the simulated moving bed; and
adjusting the production of the at least first product stream so that the first product stream exhibits a minimum conductivity.
15. The method according to claim 14 , wherein monitoring the conductivity of the metal salts in the simulated moving bed comprises monitoring a recirculation stream in the simulated moving bed.
16. The method according to claim 14 , wherein adjusting the production of the at least first product stream comprises adjusting a flow rate of a recirculation stream in the simulated moving bed.
17. A method for recovering acid and/or metals from an acid and metal salt solution, the method comprising:
providing a simulated moving bed system for chromatographically separating different components, the simulated moving bed system comprising:
at least one bed having a resin, the at least one bed comprising multiple separating sections with inlets and outlets connected in a loop so that a circulating liquid moves in sequence through the separating sections while a feed solution input stream and an aqueous eluent input stream are cyclically introduced in corresponding sequence to the loop at selected locations associated with the separating sections, and compensating product output streams are withdrawn in similarly corresponding sequence from the loop at other selected locations associated with the separating sections, all while maintaining a forward flow in a fixed direction through the loop during a plurality of steps, each of the steps commencing with the shifting of the input and output streams downstream in the loop;
feeding the feed solution input stream to the simulated moving bed, wherein the feed solution input stream comprises an acid and a metal salt;
feeding the aqueous eluent input stream to the simulated moving bed; and
removing at least a first product output stream and a second product output stream from the simulated moving bed, wherein the first product output stream comprises a higher concentration of the acid than the second product output stream.
18. The method according to claim 17 , wherein the feed solution input stream comprises one or more acids selected from the group consisting of sulfuric acid, hydrochloric acid, nitric acid, acetic acid and phosphoric acid.
19. The method according to claim 17 , wherein said simulated moving bed (SMB) is selected from the group consisting of continuous SMB, semi-continuous SMB, time variable SMB, sequential SMB, and pulsed SMB.
20. The method according to claim 17 , wherein feeding the aqueous eluent input stream to the simulated moving bed comprises continuously circulating the aqueous eluent input stream through the simulated moving bed.
21. The method according to claim 20 , wherein the aqueous eluent comprises less than 5% dissolved components.
22. The method according to claim 17 , further comprising filtering the feed solution input stream prior to feeding the feed solution input stream to the simulated moving bed.
23. The method according to claim 17 , wherein the resin comprises an anion resin.
24. The method according to claim 23 , wherein the anion resin is a weak base anion resin.
25. The method according to claim 23 , wherein the anion resin is a strong base anion resin.
26. The method according to claim 24 , wherein the anion resin is a type I anion resin.
27. The method according to claim 25 , wherein the anion resin is a type II anion resin.
28. The method according to claim 17 , comprising further processing at least one of the product output streams in a separate system, wherein the processing comprises one or more processes selected from the group consisting of chromatography, filtration, membrane treatment, evaporation, distillation, drying, gas absorption, solvent extraction, press extraction, adsorption, ion exchange and centrifugation.
29. The method according to claim 17 , further comprising recycling at least one of the at least a first product output stream and a second product output stream for re-use in a process producing the feed solution input stream.
30. The method according to claim 17 , further comprising:
monitoring conductivity of the metal salts in the simulated moving bed; and
adjusting the production of the at least first product output stream so that the first product output stream exhibits a minimum conductivity.
31. The method according to claim 30 , wherein monitoring the conductivity of the metal salts in the simulated moving bed comprises monitoring the recirculation stream in the simulated moving bed.
32. The method according to claim 30 , wherein adjusting the production of the at least first product output stream comprises adjusting a flow rate of a recirculation stream in the simulated moving bed.