CONTAMINANT FIXATION PROCESS
Rodney W. Telles, Staff Chemist and Business Manager
Samuel L. Unger, Chief Engineer
Hyman R. Lubowitz, General Manager
Environmental Protection Polymers, Inc.
Hawthorne, California 90250
INTRODUCTION
Fixation technology is required to render residues from hazardous waste volume-reduction processes safe for final disposal. Of particular concern in our work is the management of low-level radioactive pollutants and non-destructible industrial contaminants. To this end, our investigations
concern the concept and the fabrication of novel plastic modules of fixed concentrated wastes. Their
objectives are fixation products that are compact, safely transportable and stable to environmental
stresses of a landfill. Laboratory-scale modules have been thoroughly investigated and the experimental findings and process cost estimates provide the basis for scale-up of modules to a commercially
viable size 50-gallon ones. For this purpose an apparatus is being constructed under sponsorship of
the U.S. Department of Energy.
Modules are characterized by cores holding up to 90% (by weight) contaminants in polyolefinic
matrices encased by 1/4-inch thick, seamless jackets of high density polyethylene. The jackets are
formed by fusion and impregnation of resin powder onto the surfaces of the cores. The modules
have been employed to secure a broad spectrum of hazardous wastes such as electroplating residues,
pesticides, water-soluble toxic salts, arsenic-bearing filter cake and rad-waste beads, powders, and
salts. Modules were found to be readily reproducible and to provide high performance stabilization
for each waste type. In contaminant management they will assure compliance with all relevant EPA,
DOT and NRC guidelines.
Current trends in hazardous waste management focus on the destruction, detoxification or recovery and reuse of contaminants [1,2]. Nevertheless, virtually every treatment method will result in
some hazardous residue that will require disposal and its fixation is required to assure safe disposal.
Moreover, the need to minimize costs for liability, transportation and disposal in landfills has led to
greater emphasis for development of hazardous wastes volume-reduction processes. Such processes
will produce wastes with contaminant concentrations markedly greater than those in wastes managed
by current fixation techniques. To secure the cost advantages in waste management gained by volume-
reduction it will be necessary to carry out fixation of concentrated contaminants with minimal volume
added. This requirement, in our opinion, would make current fixation techniques unacceptable, or
marginally effective, for use in hazardous wastes management.
Plastic waste modules of our work are set forth as a solution to the dilemma. Our process is
geared to provide cost-effective means to manage hazardous wastes in high concentrations for safe,
final disposal. This paper reviews our process features and recent progress in managing nuclear grades
of ion-exchange resins in concentrations greater than that previously reported in the literature.
SURFACE ENCAPSULATION PROCESS
Management of concentrated contaminants with minimal added volume necessitates high performance fixation to assure environmental protection. In practice investigators have reported a sharp
escalation in technical difficulty for processing and stabilizing such wastes employing material binders
[3,4,5]. Processing problems are due mainly to rheology of concentrated mixtures. Contaminant stabilization deficiencies stem from products having greater concentrations of contaminant particles on
their surfaces and greater agglomeration and abutting of contaminant particles in their waste consignments. Leachates are thus provided enhanced opportunity to delocalize contaminants by action
on the product's surface and by channeling into its body.
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