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 RUST REMEDIAL SERVICES, INC.
(formerly offered by CHEMICAL WASTE MANAGEMENT, INC.)
(X*TRAX  Thermal Desorption)

This vendor is participating in the EPA Superfund Innovative 
Technology Evaluation (SITE) Program.  The following technology 
profile has been reproduced from the SITE Technology Profile 
document, 7th edition.  The SITE profile has been supplemented by 
MVA Consulting Inc. using information obtained from the vendor or 
from other SITE publications, referenced at the end of this file. 

                                
TECHNOLOGY DESCRIPTION:

The X*TRAX  technology is a patented thermal desorption process
that removes organic contaminants from soils, sludges, and other
solid media (see photograph below).  X*TRAX  is not, however, an
incinerator or a pyrolysis system.  Chemical oxidation and
reactions are discour-aged by maintaining an inert environment and
low treatment temperatures.  Combustion by-products are not formed
in X*TRAX , as neither a flame nor combustion gases are present in
the desorption chamber.

The organic contaminants are removed as a condensed liquid, which
is characterized by a high heat rating.  This liquid may then be
destroyed in a permitted incinerator or used as a supplemental
fuel.  Because of low operating temperatures of 400 to 1,200 de-
grees Fahrenheit (oF) and low gas flow rates, this process offers
cost effective treatment of contaminated media.

An externally-fired rotary dryer volatilizes the water and organic
contaminants from the conta-minated media into an inert carrier gas
stream.  The processed solids are then cooled with water to
eliminate dusting.  The solids can then be replaced and compacted
in their original locations.

The inert nitrogen carrier gas transports the organic contaminants
and water vapor out of the dryer.  It flows through a duct to the
gas treatment system, where organic vapors, water vapors, and dust
particles are removed and recovered.  The gas first passes through
a high-energy scrubber, which removes dust particles and 10 to 30
percent of the organic contaminants.  The gas then passes through
two condensers in series, where it is cooled to less than 40 ¿F.

Most of the carrier gas is reheated and recycled to the dryer. 
About 5 to 10 percent of the gas is separated from the main stream,
passed through a particulate filter and a carbon adsorption system,
and then discharged to the atmo-sphere.  This discharge allows
addition of make-up nitrogen to the system to keep oxygen
concentrations below 4 percent (typically below 1 percent).  The
discharge also helps maintain a small negative pressure within the
system and prevents potentially contaminated gases from leaking. 
The volume of gas released from this process vent is approximately
700 times less than an equivalent capacity incinerator.

WASTE APPLICABILITY:

The X*TRAX  process removes 1) chlorinated and non-chlorinated
volatiles and semi-volatiles, such as solvents, polychlorinated
biphenyls (PCB), and dioxins; 2) organics; and 3) heavy metals such
as mercury, from soils, sludges, and sediments.  X*TRAX  has
successfully removed PCBs from soil in a full-scale demonstration;
bench- and pilot-scale systems have removed a variety of
contaminants from soils, sludges, and sediments.  In most cases,
volatile organics are reduced to below 1 part per million (ppm),
and frequently to below the laboratory detection level. 
Semivolatile organics are typically reduced to less than 10 ppm and
frequently below 1 ppm.  Soils containing 120 to 24,000 ppm PCB
have been reduced to less than 2 ppm.  Removal efficiencies from 96
to over 99 percent have been demonstrated for soils contaminated
with various organic pesticides.  Mercury has been reduced from
5,100 ppm to 1.3 ppm.  For most materials, the system can process
120 to 280 tons per day.

STATUS:

This technology was accepted into the SITE Demonstration Program in
summer 1989.  The full-scale X*TRAX  system, Model 200, successfully 
remediated 53,000 tons of PCB-conta-minated soil at the
Re-Solve, Inc., Superfund site in Massachusetts.  The system has
treated up to 280 tons of soil per day to less than 2 ppm PCB; the
site's treatment standard is 25 ppm.  EPA conducted a SITE demon-
stration in May 1992, during this remediation.  During the
demonstration, the system operated reliably.  Average PCB
concentrations in the treated soils were 0.13 milligrams per
kilogram; no dioxins or dibenzofurans were formed during treatment. 
The vent gas met all appropriate permit require-ments and emitted
less than 0.4 grams of orga-nics per day to the atmosphere.  The
Applica-tions Analysis Report will be published in late 1994.

RUST Remedial Services currently has laboratory-, pilot-, and full-
scale X*TRAX  systems.  Two laboratory-scale, continuous pilot
systems are available for treatability studies.  Both systems are
operated at RUST's Clemson Technical in South Carolina:  one treats
mixed Resource Conservation and Recovery Act (RCRA)/radioactive
wastes; the other treats RCRA and Toxic Substances Control Act
wastes.  More than 108 tests have been completed since January 1988.

FOR FURTHER INFORMATION:

EPA PROJECT MANAGER:
Paul dePercin
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, OH  45268
513-569-7797
Fax: 513-569-7620

TECHNOLOGY DEVELOPER CONTACT:
Chetan Trivedi
RUST Remedial Services, Inc.
7250 West College Drive
Palos Heights, IL  60463
708-361-7520/8400
Fax: 708-361-9545
__________________________________________________________

Sources of information in this profile:

EPA Superfund Innovative Technology Evaluation Program 
        Technology Profiles Seventh Edition, November 1994. 
        EPA/540/R-94/526.

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