Herman J Hittner

US Patent:

50248227, Jun 18, 1991

Filed:

Mar 30, 1990

Appl. No.:

7/502185

Inventors:

Herman J. Hittner - Lower Burrell PA
Quyen C. Nguyen - Newburgh IN

Assignee:

Aluminum Company of America - Pittsburgh PA

International Classification:

C01F 702

US Classification:

423111

Abstract:

A process for treating spent potlining from the electrolytic smelting of aluminum in cryolite includes incinerating the potlining to combust carbonaceous material to form an ash at a temperature low enough to maintain low fluorine vapor pressures, admixing siliceous material with the potlining either before of after the ash-forming stage, and heating the ash and siliceous material to form a glassy residue. The residue formed by the process of the present invention produces a spent potlining suitable for landfill characterized by a low leachability of fluorine in water.

US Patent:

49561588, Sep 11, 1990

Filed:

Mar 29, 1988

Appl. No.:

7/174863

Inventors:

Quyen C. Nguyen - Lower Burrell PA
Herman J. Hittner - Lower Burrell PA

Assignee:

Aluminum Company of America - Pittsburgh PA

International Classification:

C01F 702

US Classification:

423111

Abstract:

The present invention provides a process for treating spent potlining from the electrolytic smelting of aluminum in cryolite including burning the spent potlining to form an ash, mixing with a siliceous material either before or after the ash-forming step, and heating to form a residue suitable for landfill. The ash and siliceous material are mixed in a specified mole ratio of at least about 1. 4 silicon to sodium. The process further includes cooling the residue rapidly. The residue formed by the process of the present invention produces a spent potlining suitable for landfill characterized by a low leachability of fluorine in water.

US Patent:

54769906, Dec 19, 1995

Filed:

Jun 29, 1993

Appl. No.:

8/084896

Inventors:

Herman J. Hittner - Lower Burrell PA
R. Lee Byers - Upper St. Clair PA
John N. Lees - Brookfield WI
David W. Rierson - Elm Grove WI

Assignee:

Aluminum Company of America - Pittsburgh PA

International Classification:

A62D 300
C01F 702
B09B 300

US Classification:

588201

Abstract:

An industrial waste management facility (IWMF) for disposing of spent potlining includes a co-current gas-fired rotary kiln for containing a molten pool of spent potlining throughout the entire length of the rotary kiln from the inlet to the outlet, an ash quencher and cooler for receiving molten residue from the discharge end of the rotary kiln, a secondary combustion chamber, and a down-draft transition chamber for channeling discharge gases from the rotary kiln to the secondary combustion chamber. Pneumatic injection slingers feed and distribute spent potlining into the inlet end of the rotary kiln. A discharge dam provides a predetermined average depth of molten bath material in the rotary kiln over its entire length. A blended ratio of comminuted materials injected through the pneumatic injection slinger feeder is adjusted and controlled in response to signals received from a radiative optical kiln bath temperature measurement system. The IWMF recovers fluorides from discharge gases exiting the secondary combustion chamber, recycles the fluorides to the molten bath or pool of the rotary kiln, and collects and withdraws glass frit residue from the ash quencher and cooler.

US Patent:

57110182, Jan 20, 1998

Filed:

Feb 21, 1995

Appl. No.:

8/392002

Inventors:

Herman J. Hittner - Lower Burrell PA
R. Lee Byers - Upper St. Clair PA
John N. Lees - Brookfield WI
David W. Rierson - Elm Grove WI

Assignee:

Aluminum Company of America - Pittsburgh PA

International Classification:

A62D 300
C01F 702
B09D 300

US Classification:

588201

Abstract:

An industrial waste management facility (IWMF) for disposing of spent potlining includes a co-current gas-fired rotary kiln for containing a molten pool of spent potlining throughout the entire length of the rotary kiln from the inlet to the outlet, an ash quencher and cooler for receiving molten residue from the discharge end of the rotary kiln, a secondary combustion chamber, and a down-draft transition chamber for channeling discharge gases from the rotary kiln to the secondary combustion chamber. Pneumatic injection slingers feed and distribute spent potlining into the inlet end of the rotary kiln. A discharge dam provides a predetermined average depth of molten bath material in the rotary kiln over its entire length. A blended ratio of comminuted materials injected through the pneumatic injection slinger feeder is adjusted and controlled in response to signals received from a radiative optical kiln bath temperature measurement system. The IWMF recovers fluorides from discharge gases exiting the secondary combustion chamber, recycles the fluorides to the molten bath or pool of the rotary kiln, and collects and withdraws glass frit residue from the ash quencher and cooler.

US Patent:

56162960, Apr 1, 1997

Filed:

Feb 21, 1995

Appl. No.:

8/391894

Inventors:

Herman J. Hittner - Lower Burrell PA
R. Lee Byers - Upper St. Clair PA
John N. Lees - Brookfield WI
David W. Rierson - Elm Grove WI

Assignee:

Aluminum Company of America - Pittsburgh PA

International Classification:

C21B 722

US Classification:

266145

Abstract:

An industrial waste management facility (IWMF) for disposing of spent potlining includes a co-current gas-fired rotary kiln for containing a molten pool of spent potlining throughout the entire length of the rotary kiln from the inlet to the outlet, an ash quencher and cooler for receiving molten residue from the discharge end of the rotary kiln, a secondary combustion chamber, and a down-draft transition chamber for channeling discharge gases from the rotary kiln to the secondary combustion chamber. Pneumatic injection slingers feed and distribute spent potlining into the inlet end of the rotary kiln. A discharge dam provides a predetermined average depth of molten bath material in the rotary kiln over its entire length. A blended ratio of comminuted materials injected through the pneumatic injection slinger feeder is adjusted and controlled in response to signals received from a radiative optical kiln bath temperature measurement system. The IWMF recovers fluorides from discharge gases exiting the secondary combustion chamber, recycles the fluorides to the molten bath or pool of the rotary kiln, and collects and withdraws glass frit residue from the ash quencher and cooler.