United States
Environmental Protection
Agency
EPA/540/F-92/010
September 1992
&EPA
SUPERFUND INNOVATIVE
TECHNOLOGY EVALUATION
Emerging Technology Bulletin
The Babcock & Wilcox Cyclone Furnace
Soil Vitrification Technology
Babcock & Wil
Technology Description: The B&W Cyclone Furnace is a
high temperature thermal treatment technology which is capable
of vitrifying soil. For this project, B&W's 4- to 6-million BTU/hr
pilot furnace, located at its Alliance, OH research center, was
used. This system is shown in Figure 1. This water-cooled furnace
was fired using natural gas as the fuel. Combustion air is intro-
duced tangentially to the Cyclone. Soil enters the center of the
Cyclone furnace and is retained along its walls by the cyclonic
action of the tangentially introduced combustion air. Gas tem-
peratures within the Cyclone reach temperatures between 2000
and 3000 °F during operation. Soil within the Cyclone is melted
and reaches temperatures of more than 2400°F. This molten soil
flows out of the Cyclone furnace and is quench cooled with
water. Upon cooling, the treated soil forms an obsidian-like vitrified
mass. Exhaust gas from the Cyclone passes through a heat
exchanger where it is cooled to 200°F. From there the exhaust
gas enters a baghouse to remove particulates before release to
the atmosphere.
Project Description: The B&W Cyclone Furnace was de-
signed for use in power generation and not waste treatment.
Because of the process conditions described above, however,
EPA believed that this technology may be capable of effectively
vitrifying metal contaminated soil. To determine whether this was
true, a study was designed which would allow for an evaluation of
the vitrification capabilities of the Cyclone Furnace.
First, a moisture-free Synthetic Soil Matrix (SSM) prepared by
EPA, was studied. The SSM was spiked with 7000 ppm lead,
1000 ppm cadmium and 1500 ppm chromium. This material
failed the TCLP test for lead and cadmium by producing leachate
containing more than 10 times the regulated level of metal. For
reasons that are not well understood, the SSM did not fail the
TCLP test for chromium. After studying the relevant physical
properties of the SSM, the Cyclone Furnace was modified and 6
tons of SSM was treated at a feedrate of 50 to 150 Ib/hr. During
these tests measurements were taken to monitor the process,
measure the amount of metal that escaped in the furnace ex-
haust, measure the volume reduction and assess the quality of
the vitrified slag produced.
Results: The results of this study show that the Babcock &
Wiicox 6 million BTU/hr pilot Cyclone Furnace was able to:
COX
1. Produce a vitrified slag that passed the TCLP test from an
EPA SSM containing, 7000 ppm lead, 1000 ppm cadmium
and 1500 ppm chromium
2. Incorporate from 95% to 97% of the input SSM within the
slag
3. Maintain stable cyclone operation during soil treatment.
SSM Feed
System
SSM
Sampling
Location
Stag and
Quench •
Wafer
Sampling
Location
Continuous Emissions
.,,.,. Monitor (CEM)
Sampling Location Sampling Location
Stack Paniculate
'ID Fan
Furnace
Stack
Natural
Gas
Soil
Injector
Slag
Trap
Cyclone
Barrel
.Slag
Quenching
Tank
Figure 1, B&W Cyclone Furnace Facility.
GX Printed on Recycled Paper
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4 Produce exhaust gasses that contain acceptable levels of CO
and NO,,
5, Increase the capture of heavy metats In the slag with increas-
ing faed rate artd with decreasing metal volatility,
S, Raduc© the volume of the synthetic soil matrix by 25% to
35% (dry basis),
A report summarizing the results of this study will be available in
the Fa!! of 1992,
For Further Information:
EPA Project Manager:
Laurel StaTey
U,S. EPA Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 452B8
(513) 569-7863
United States
Environmental Protection Agency
Center for Environmental Research Information
Cincinnati, OH 45268
Offclai Business
Psnatty for Private Use
$300
EPA.64GJF-92/010
BULK RATE
POSTAGE & FEES PAID
EPA
PERMIT No. G-35
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