32    AQUEOUS PYROLYSIS OF INDUSTRIAL WASTES
David L. Kincannon, Graduate Student
Don F. Kincannon, Professor
School of Civil Engineering
William L. Hughes, Professor and Director
The Engineering Energy Laboratory
School of Electrical and Computer Engineering
Oklahoma State University
Stillwater, Oklahoma 74078
INTRODUCTION
Industrial wastes present many problems with regard to their disposal or treatment. Improper
handling of industrial wastes can lead to pollution problems and public health hazards. Large quantities of industrial wastes are generated continuously which must have adequate treatment facilities or
available space for disposal. Solid waste disposal in approved sanitary landfills can require large areas
of land. If the industrial waste is a hazardous material, it must be disposed of in a permitted
hazardous waste landfill. The land for these landfills must consist of a suitable soil type and an
acceptable location that is near the source of waste generation and not in a place that is susceptible to
flooding. Public opposition is usually great because nobody wants to have disposal or treatment
facilities for wastes located in their vicinity. The opposition is due to the risks of pollution and the
possibilities of unpleasant aesthetics and odor problems. This paper presents an investigation into the
use of the aqueous pyrolysis method using induction heating that has been developed by Dr. William
L. Hughes and co-workers (1) as a method of treating industrial wastes and other solid wastes.
PREVIOUS WORK
Research previously done on pyrolysis has provided helpful information in several areas. Hughes
and Ramakumar [1] used aqueous pyrolysis of biomass as a method for generating energy using
various biomass waste products as the sources of fuel. They found that the process yielded a gaseous
product nearly evenly divided between carbon dioxide and combustible hydrocarbon gases. Their
process used induction heating of a batch reactor to pyrolyze cotton, saw dust, newsprint, coal dust,
and plant materials [1].
Bohn and Benham [2] in their study of biomass pyrolysis using an entrained flow tubular reactor of
a wheat straw feedstock with a steam carrier gas measured the gas yield, gas composition, and process
heat of the pyrolysis process. Gas yields of 91% were measured at 950°C, and the process heat was
measured in the range of 2300-3000 J/g of pyrolysis gas. The composition of gases was found to be
52% CO, 20% H2, 11 % methane, 8% C02, 5% ethylene, and 4% other gases. This study showed that
the pyrolysis was strongly influenced by the reactor temperature and not by the steam to biomass ratio
[21-
Kemmler and Schlich [3] investigated the use of pyrolysis for the volume reduction of organic
wastes. The process was used for pyrolyzing nuclear wastes and spent solvents. The volume reduction
of nuclear wastes was 50% and mass reduction was 20%. There was a 7% reduction of volume and
nearly 6% reduction of mass of the solvent that was pyrolyzed [3].
PROCESS DESCRIPTION
Aqueous pyrolysis is the conversion of a sample mixed with water into another substance or
substances by subjecting the material to high temperature and high pressure [4]. The water is used to
replace air in void spaces of the material. Due to thermal fission, the process generally leads to the
production of molecules of lower mass. The process results in the decomposition of the material into
char, carbon dioxide, methane, and other hydrocarbon gases such as ethane and ethylene. The
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