Apparatus and method for separating liquid oxygen from liquified air

Patent metadata

Field	Value
Publication number	US-11746013-B2
Application number	US-201716313336-A
Country	US
Kind code	B2
Filing date	Jun 27, 2017
Priority date	Jun 27, 2016
Publication date	Sep 5, 2023
Grant date	Sep 5, 2023

Abstract

An apparatus and method of separation of LOX and other commercially valuable components, such as LAr from liquefied air, which consists primarily of LN2. Strong magnetic field gradient and gravity are used to separate LOX from liquefied air, based upon the different magnetic properties of LOX and LN2. The apparatus and method employ a magnetic field gradient to levitate the LN2 and LAr diamagnetic components of liquid air while accelerating the paramagnetic LOX component toward the bottom to achieve oxygen separation. In other embodiments, a leak valve system can be used.

First claim

What is claimed is:

1. A method of separating liquid oxygen from liquid air comprising:
(a) storing liquid air in a liquid air storage container, wherein the liquid storage container comprises
(i) a bottom section that has a portion of the liquid air that is rich in liquid oxygen due to gravity, and
(ii) a top portion that has air vapor;

(b) flowing liquid air from the bottom section to a separation system, wherein the separation system comprises a magnetic field system and a leak valve system;
(c) utilizing the separation system to separate liquid oxygen from the liquid air that is rich in liquid oxygen; and
(d) collecting the liquid oxygen in a second storage container.

2. The method of claim 1 , wherein the liquid oxygen is collected in the second storage container via gravity.

3. The method of claim 1 , wherein the utilizing the separation system comprises utilizing the magnetic field to levitate liquid oxygen from the liquid air based upon the different magnetic properties of liquid oxygen and liquid nitrogen.

4. The method of claim 1 , wherein the magnet comprises a gradient coil.

5. The method of claim 4 , wherein the gradient coil is wound to achieve a field and gradient that is between about 105% and about 140% of the requirement to levitate liquid oxygen.

6. The method of claim 4 , wherein the gradient coil is wound to achieve a field and gradient that is between about 8.5 T 2 /m and about 11.5 T 2 /m.

7. The method of claim 1 , wherein the utilizing the separation system comprises utilizing the leak valve system using one or more adjustable controllers and sensors to separate liquid oxygen from the liquid air.

8. The method of claim 1 , wherein the collecting liquid oxygen in the second storage container comprises collecting ultra-pure liquid oxygen in the second container.

9. The method of claim 8 , wherein the ultra-pure liquid oxygen is at least about 98% liquid oxygen by weight.

10. The method of claim 8 , wherein the ultra-pure liquid oxygen is at least about 99.5% liquid oxygen by weight.

11. The method of claim 8 , wherein the ultra-pure liquid oxygen is at least about 98% liquid oxygen by mole.

Assignees

• Univ Texas Tech System

Inventors

• Duncan Robert V

Classifications

• C01B13/0248 Primary

  Physical processing only · CPC title

• B01D17/0214

  with removal of one of the phases · CPC title

• B01D19/00

  Degasification of liquids · CPC title

• F17C5/02

  for filling with liquefied gases · CPC title

• F25J3/04636

  using a hybrid air separation unit, e.g. combined process by cryogenic separation and non-cryogenic separation techniques (F25J3/04733 and F25J3/04757 take precedence) · CPC title