Francis A Altemose

US Patent:

52201112, Jun 15, 1993

Filed:

Sep 10, 1991

Appl. No.:

7/757361

Inventors:

Donald P. Bucci - Mertztown PA
Francis A. Altemose - Long Pond PA
Nancy C. Easterbrook - Macungie PA
Edwin N. Givens - Bethlehem PA
Joseph Klosek - Wescosville PA
Kenneth D. Tracy - Randolph NJ
Kai P. Wong - Allentown PA

Assignee:

Air Products and Chemicals, Inc. - Allentown PA

International Classification:

C04B 1808
C04B 1806
C04B 1400
C04B 1830

US Classification:

580256

Abstract:

Fly ash generated from incineration of municipal solid waste (MSW) when placed in landfills under mild acid conditions can leach lead and cadmium. A process for stabilizing heavy metals in this fly ash is presented which involves calcining in the presence of an oxygen containing gas stream at a temperature greater than about 375. degree. C. and substantially less than about 800. degree. C. for times from about 170 seconds up to about 5 hours fly ash which has been subjected to lime scrubbing for acid gas removal. Such treated MSW fly ash will give leachates containing heavy metal concentrations less than the EPA regulatory limit.