Lead emission standards and research top division highlights.

Lead Emission Standards and Research Top Division Highlights

The Environmental Control Division teamed up with several other divisions this year to present papers and panel discussions on topics of interest to members of each. With the Brass & Bronze Division, one of three papers described research conducted by The Univ of Alabama Mineral Resources Institute directed toward the recovery of values from waste foundry material and the respective environmental problems.

A major effort of this program, said E. Lamotte, who presented the paper for his colleagues B. Tippin, The Univ of Alabama, and R. Tate, a foundry consultant, has been the processing of waste molding sand from brass foundries for recovery of the contained metal and sand.

The result was a process using magnetic separation to recover about 90% of the metal from the sand and subsequent sand calcining to meet EPA standards, thus permitting unregulated use.

Lamotte described the recovery process and its successful implementation, presenting resulting data from a plant that has installed the sand reclaim system. The bottom line is that the volume of material now being handled as a hazardous waste at the foundry is less than 5% of the original waste sand feed. The detoxified sand can either be reused within the foundry to make molds and cores, or sold as a by-product.

T. Piwonka, The Metal Casting Technology Center/The Univ of Alabama, then gave an interim report of AFS research conducted to study the effects of alloy content, superheat and flux covers on the evolution of lead from the bath to develop melting methods that permit lead-containing copper-base alloys to be melted while generating the minimum of airborne lead.

The results presented were preliminary but, according to Piwonka, the highest lead emissions came from the highest zinc-containing alloys and melt superheat temperature is important in controlling the lead emissions. A flux cover could be developed to cut down on these emissions; however, more investigation is necessary.

An EC/Molding Methods & Materials joint session addressed the recent declaration of silica as a "possible human carcinogen" by the International Agency for Research on Cancer (IARC). R. Glenn, National Industrial Sand Assn, reviewed epidemiology studies which looked for an association of lung cancer deaths to silica exposure. He criticized the pathology employed in these studies and the conclusions that were drawn.

"It is premature to conclude that crystalline silica is a cause of lung cancer," Glenn said. "This does not preclude the possibility, but points out the need for further study."

Nonetheless, the IARC conclusion is cause for concern, pointed out G. Mosher, American Foundrymen's Society. "Regulatory agencies will start using these findings to regulate silica," he said, indicating an EPA review of the finding has already been announced. "Silica has already been placed on California's list of carcinogens," Mosher added.

In another AFS Research Report on "The Leaching of Organic Matter from Ferrous Foundry Process Wastes," by R. K. Ham, W. C. Boyle, E. C. Engroff and R. L. Fero, Univ of Wisconsin/Madison, Ham described the program undertaken to determine the potential for and extent of contamination of groundwater adjacent to foundry waste landfills by organic matter arising from the wastes. The complete report begins on page 27 of this issue.

A panel discussion of environmental regulations included the essentials of "What's Coming from OSHA," presented by C. Robinson, RMT, Inc; "What's Coming from Congress," by C. Sheehan, American Cast Metals Assn; and "What's Coming from EPA," by R. Smith, Tyler Pipe Industries.

PHOTO : Pete Aldred (l), Intermet/Lynchburg Foundry Div, session chairman, talks withR. Ham,

PHOTO : Univ of Wisconsin/Madison, prior to Ham's report of AFS Research into the leaching of

PHOTO : organic compounds.