A Study of Heavy Metal Emissions From
Fluidized Bed Incinerators
BRIAN J. COPELAND. Manager
Technical Services
Copeland Systems. Incorporated
Oakbrook, Illinois 60521
INTRODUCTION
Over the past ten years. Government regulatory agencies and designers of pollution
control equipment have become increasingly aware of the need for an advanced study of the
effect of heavy metal emissions on the environment. Heavy metals form organic complexes
with human enzymes which have an adverse effect on the central nervous system and the
ability of the blood to absorb life giving oxygen. Science has defined dangerous blood level
concentrations, but specific municipal and industrial emission levels are yet to be fully
specified. Obvious sources: automobiles, lead smelting facilities, and chlorine caustic soda
plants have been required to modify their effluent streams to reduce heavy metal output.
The Environmental Protection Agency's task force on sewage sludge incineration studied
the emissions from five municipal incinerators in 1971 (Lake Tahoe and Barstow.
California; Loron. Virginia: Waldwick, New Jersey: and Monterey, California) and
concluded that these particular incinerators were in compliance with established
regulations for particulate and gaseous emissions. However, their analyses of heavy metals
only concluded that further study was required. To date, the only published air pollution
regulations is a mass emission of 3.200 grams per day for the element mercury. Industrial
threshold limits have been defined for other elements for personnel health and safety. The
Environmental Protection Agency (EPA) has published "Emission Factors For Trace
Substances" (I). No legality has been attached to either of these guidelines.
The need for specific regulations came to light in March of 1974. The operation of all
sewage sludge incinerators in Prince George's County. Maryland was banned. The
injunction was based on allegations that the operation of the fluidized bed incinerators at
the Piscataway Waste Treatment Plant for a total of 73 hours had been responsible for the
blood lead level of three children in the Piscataway Hills area being 40 to 43 micrograms of
lead per 100 milliliters. Mr. Daniel Snyder of the EPA stated to the Washington Post that,
"It is highly unlikely almost to the point of being impossible that there is a cause-etfect
relationship between the use of these incinerators and the levels of lead in the children" (2).
The proximity of the Piscataway plant to the greater Washington area and the Washington
Capital Beltway were deemed the most probable cause, but the problem had been reduced
from one of technology to one of public emotion and the operation and startup of sludge
incinerators in Prince George's County was held in limbo until September of 1974.
In the interim period, an independent heavy metal analysis was conducted on a fluid
bed incinerator, in Downingtown, Pennsylvania, similar to those at the Piscataway and
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