Harry M Cheung

US Patent:

45740062, Mar 4, 1986

Filed:

Aug 16, 1984

Appl. No.:

6/641553

Inventors:

Harry Cheung - Buffalo NY

Assignee:

Union Carbide Corporation - Danbury CT

International Classification:

F25J 304

US Classification:

62 22

Abstract:

A process which produces a krypton-xenon concentrate from a liquid feed while also producing a liquid product substantially free of rare gases. The process employs an integral heat pump circuit to carry out the separation in an energy-efficient manner.

US Patent:

43991203, Aug 16, 1983

Filed:

Dec 26, 1979

Appl. No.:

6/106738

Inventors:

Harry Cheung - Buffalo NY

Assignee:

Union Carbide Corporation - Danbury CT

International Classification:

C01B 500

US Classification:

423648A

Abstract:

Deuterium is concentrated in a hydrogen-water isotopic exchange process enhanced by the use of catalyst materials in cold and hot tower contacting zones. Water is employed in a closed liquid recirculation loop that includes the cold tower, in which deuterium is concentrated in the water, and the upper portion of the hot tower in which said deuterium is concentrated in the hydrogen stream. Feed water is fed to the lower portion of said hot tower for contact with the circulating hydrogen stream. The feed water does not contact the water in the closed loop. Catalyst employed in the cold tower and the upper portion of the hot tower, preferably higher quality material, is isolated from impurities in the feed water that contacts only the catalyst, preferably of lower quality, in the lower portion of the hot zone. The closed loop water passes from the cold zone to the dehumidification zone, and a portion of said water leaving the upper portion of the hot tower can be passed to the humidification zone and thereafter recycled to said closed loop. Deuterium concentration is enhanced in said catalytic hydrogen-water system while undue retarding of catalyst activity is avoided.

US Patent:

40584852, Nov 15, 1977

Filed:

Jun 21, 1976

Appl. No.:

5/698030

Inventors:

Harry Cheung - Buffalo NY

Assignee:

Union Carbide Corporation - New York NY

International Classification:

B01J 2104
B01J 2342
B01J 2344
B01J 3502

US Classification:

252466PT

Abstract:

A porous composite structure comprising a sintered mixture of metal particles and alumina particles, and a method for producing this composite. The composite is useful as a catalyst support, particularly in apparatus designed to reduce pollutant emissions from automobile engines.

US Patent:

49341480, Jun 19, 1990

Filed:

May 12, 1989

Appl. No.:

7/350848

Inventors:

Ravi Prasad - East Amherst NY
Oscar W. Haas - Cheektowaga NY
Harry Cheung - Buffalo NY

Assignee:

Union Carbide Corporation - Danbury CT

International Classification:

F25J 302

US Classification:

62 24

Abstract:

Feed air to a prepurifier adsorption system/cryogenic air separation system for dry, high purity nitrogen and/or oxygen production is dried in a membrane dryer preferably characterized by a countercurrent flow path. Drying is enhanced by the use of purge gas on the permeate side of the membrane dryer, which adsorption system or cryogenic air separation system product or waste gas, dried feed air or ambient air being used as purge gas.

US Patent:

51613808, Nov 10, 1992

Filed:

Aug 12, 1991

Appl. No.:

7/743734

Inventors:

Harry Cheung - Williamsville NY

Assignee:

Union Carbide Industrial Gases Technology Corporation - Danbury CT

International Classification:

F25J 304
F25J 306

US Classification:

62 22

Abstract:

A cryogenic rectification system comprising two cryogenic rectification plants wherein a fluid mixture comprising argon and nitrogen is withdrawn in a defined manner from the first plant and passed into the second plant such that argon production is enhanced to more than offset the additional separation power requirements.

US Patent:

6301923, Oct 16, 2001

Filed:

Mar 21, 2001

Appl. No.:

9/813012

Inventors:

Dante Patrick Bonaquist - Grand Island NY
Harry Cheung - Williamsville NY
Arun Acharya - East Amherst NY

Assignee:

Praxair Technology, Inc. - Danbury CT

International Classification:

F25D 900
F25J 300
F25B 900

US Classification:

62402

Abstract:

A method for generating refrigeration for application to a heat load, especially at very cold temperatures, using an environmentally benign working gas such as air and using an upstream precooling circuit to reduce or eliminate inefficiencies stemming from warm end pinch.

US Patent:

50748980, Dec 24, 1991

Filed:

Apr 3, 1990

Appl. No.:

7/504630

Inventors:

Harry Cheung - Buffalo NY

Assignee:

Union Carbide Industrial Gases Technology Corporation - Danbury CT

International Classification:

F25J 300
F25J 302

US Classification:

62 38

Abstract:

A cryogenic air separation method for the production of oxygen and medium pressure nitrogen comprising a primary higher pressure column and an auxiliary smaller lower pressure stripping column wherein primary column bottom liquid is employed as stripping column downflow liquid and primary column top vapor condenses against stripping column bottom liquid to generate stripping vapor.

US Patent:

43459250, Aug 24, 1982

Filed:

Nov 26, 1980

Appl. No.:

6/210733

Inventors:

Harry Cheung - Kenmore NY

Assignee:

Union Carbide Corporation - Danbury CT

International Classification:

F25J 304

US Classification:

62 13

Abstract:

Oxygen gas is produced at greater than atmospheric pressure by separating air into oxygen-rich and nitrogen-rich fractions in a distillation column, removing the oxygen as liquid and pumping it to the desired pressure and subsequently vaporizing the pumped liquid oxygen by means of energy absorbed from a recirculation argon containing fluid.