Systems and methods for recovery of rare-earth constituents from environmental barrier coatings

Patent metadata

Field	Value
Publication number	US-9409185-B2
Application number	US-201414255650-A
Country	US
Kind code	B2
Filing date	Apr 17, 2014
Priority date	Apr 17, 2014
Publication date	Aug 9, 2016
Grant date	Aug 9, 2016

Abstract

Systems and methods for recovery of rare-earth constituents from environmental barrier coatings (EBCs) are provided. One method includes for separating rare-earth (RE) containing constituents from a particulate feedstock containing a mixture of RE silicates and non-magnetic constituents includes disposing a collection member in a vicinity of the feedstock and magnetizing the collection member to generate a magnetic field sufficient to selectively attract the RE silicates to the collection member. The method further includes removing the RE silicates from the collection member.

First claim

What is claimed is:

1. A method for separating rare-earth (RE) containing constituents from a particulate feedstock containing a mixture of RE silicates and non-magnetic constituents, the method comprising:
disposing a collection member in a vicinity of the feedstock;
magnetizing the collection member to generate a magnetic field sufficient to selectively attract the RE silicates to the collection member;
removing the RE silicates from the collection member; and
removing the non-magnetic constituents by rinsing the collection member while the magnetic field is applied.

2. The method of claim 1 , wherein removing the RE silicates comprises stopping application of the magnetic field to the collection member, thereby causing release of the RE silicates from the collection member.

3. The method of claim 1 , wherein the RE silicates have paramagnetic properties, and wherein applying the magnetic field comprises applying a magnetic field of at least 0.5 Tesla.

4. The method of claim 1 , wherein the feedstock comprises an RE disilicate in the form of RE 2 Si 2 O 7 (REDS) that includes Ytterbium (Yb).

5. The method of claim 4 , wherein the feedstock comprises REDS and at least one of RE 2 SiO 5 (REDS), (Ba,Sr)Si 2 Al 2 O 8 (BSAS) or Si, and wherein separating and removing the non-magnetic contaminants comprises separating and removing at least one of the REMS, the BSAS or the Si.

6. The method of claim 1 , further comprising dispersing the feedstock in a medium.

7. The method of claim 1 , further comprising performing feedstock preparation prior to separation, including at least one of (i) comminuting the feedstock to decrease a particle size of the feedstock or liberate RE-containing constituents from agglomerates, (ii) screening or sieving the feedstock to remove oversized particles, (iii) performing flotation separation of the feedstock to remove low-density constituents or contaminants, (iv) performing low-field magnetic separation on the feedstock to remove ferromagnetic contaminants, and (v) dispersing the feedstock in a liquid medium.

8. The method of claim 1 , wherein magnetizing the collection member comprises using at least one electromagnet to magnetize the collection member.

9. A system for collection and recovery of rare-earth (RE) containing constituents from a powder feedstock having RE-containing constituents, the system comprising:
a magnetic field generator configured to apply a magnetic field;
a magnetizable collection member disposed in a vicinity of the powder feedstock, the applied magnetic field causing the RE-containing constituents to selectively attract to the collection member to affect separation of the RE-containing constituents from the powder feedstock; and
a collection and recovery system having a conveyor system configured to move the powder feedstock, wherein the magnetic field moves RE-containing constituents from the conveyor as the powder feedstock passes through the magnetic field.

10. The system of claim 9 , further comprising a collection and recovery system configured to rinse the collection member while the magnetic field is applied.

11. The system of claim 9 , further comprising a collection and recovery system configured to stop application of the magnetic field to the collection member, thereby causing release of the separated RE-containing constituents from the collection member to thereby collect the RE-containing constituents.

12. The system of claim 9 , wherein the RE-containing constituents have paramagnetic properties and wherein the magnetic field generator is further configured to apply a magnetic field of at least 0.5 Tesla.

13. The system of claim 9 , wherein the powder feedstock comprises an RE disilicate RE 2 Si 2 O 7 (REDS) that includes Ytterbium (Yb).

14. The system of claim 9 , wherein the powder feedstock comprises Yttrium (Y) and Ytterbium (Yb) in the form of YbYDS, and further comprising a collection and recovery system configured to separate the YbYDS from the remainder of the powder feedstock.

15. The system of claim 9 , further comprising a collection and recovery system configured to disperse the feedstock in a medium.

16. The system of claim 9 , further comprising a collection and recovery system configured to, prior to separation, one of (i) comminute the feedstock to decrease a particle size of the feedstock or liberate RE-containing constituents from agglomerates, (ii) screen or sieve the feedstock to remove oversized particles, (iii) perform flotation separation of the feedstock to remove low-density constituents or contaminants, (iv) perform low-field magnetic separation on the feedstock to remove ferromagnetic contaminants, and (v) disperse the feedstock in a liquid medium.

17. The system of claim 9 , wherein the collection and recovery system is further configured to use at least one electromagnet to apply the magnetic field.

18. The system of claim 9 , wherein the magnetic field generator is further configured to apply a magnetic field of less than 0.5 Tesla to separate ferromagnetic particles from the powder feedstock.

Assignees

• Gen Electric

Inventors

• Manepalli Satya Kishore
• Grossman Theodore Robert
• Lipkin Don Mark
• Gourishankar Karthick Vilapakkam

Classifications

• B03C1/02 Primary

  acting directly on the substance being separated · CPC title

• B03C1/28

  Magnetic plugs and dipsticks · CPC title

• B03C1/30

  Combinations with other devices, not otherwise provided for · CPC title

• B02C23/10

  with separator arranged in discharge path of crushing or disintegrating zone · CPC title

• Y02P10/20

  Recycling · CPC title