?/EPA
                           United States
                           [Environmental Protection
                           Agency
EPA/540/SR-95/504
May 1995
                         SUPERFUND INNOVATIVE
                         TECHNOLOGY EVALUATION
                           Emerging  Technology
                           Summary

                           Reclamation  of  Lead  from
                           Superfund  Waste  Material  Using
                           Secondary  Lead  Smelters
                           Stephen W. Paff and Brian E. Bosilovich
                            Hundreds of sites across the United
                           States are contaminated with lead from
                           various sources. Through a Coopera-
                           tive Agreement with the U.S. Environ-
                           mental Protection Agency's (EPA) Risk
                           Reduction Engineering Laboratory, the
                           Center for  Hazardous Materials Re-
                           search (CHMR), in  conjunction with a
                           major secondary lead smelter, has dem-
                           onstrated that secondary lead smelters
                           may be used economically to reclaim
                           lead from a wide range of lead-contain-
                           ing materials frequently found at Su-
                           perfund sites. Such materials include
                           battery case  materials, lead dross, and
                           other debris containing greater than 1%
                           lead.
                            During the study,  CHMR and the
                           smelter reclaimed lead from five sets
                           of materials, including two Superfund
                           sites containing primarily battery cases
                           and  one battery breaker/smelter site
                           with a variety of lead-containing mate-
                           rials. Between 4 and 1500 tons of ma-
                           terials from each of these sites were
                           excavated or collected and processed
                           at the smelter, while the research team
                           assessed the effects on furnace opera-
                           tion and performance. Two additional
                           sets of materials, one from the demoli-
                           tion of a house containing lead-based
                           paint and the other from work on  a
bridge coated with lead paint, were also
processed in the smelter. The results
showed that it was technically feasible
to use the secondary lead  smelter to
reclaim lead from all of the materials.
 CHMR also assessed the economics
of using  secondary  lead smelters to
reclaim lead from Superfund sites and
developed a method for estimating the
cost of reclaiming lead. This method
develops cost as a function  of material
excavation, transportation, and pro-
cessing costs combined with cost ben-
efits received by the smelter (in the
form of recovered lead, reduced fuel
usage, and/or reduced iron usage). The
total remediation costs using second-
ary lead smelters for the sites and ma-
terials studied varied between $35 and
S374/ton, based on a conservative mar-
ket price  for lead. The costs were pri-
marily a function of lead concentration,
the market price for lead, distance from
the smelter, and the amount of materi-
als that became incorporated into slag
from the  process, although other fac-
tors affected the economics as well.
Materials with high concentrations of
lead were significantly less expensive
to remediate than those with low con-
centrations. The cost to remediate ma-
terials that left few slag residues in the
                                                                      Printed on Recycled Paper

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furnace was significantly lower than the
cost to remediate materials that con-
tained significant slagging components.
  This Project Summary was developed
by  EPA's Risk Reduction Engineering
Laboratory, Cincinnati, OH, to announce
key findings of  this SITE  Emerging
Technology Project that are fully docu-
mented in a separate report of the same
title (see Project Report ordering infor-
mation at back).

Introduction
  Lead is used in  the production of  vari-
ous consumer and commercial items, from
automobile and  equipment  batteries to
paints to crystal. This widespread use has
made it one of the most frequent contami-
nants at sites on  the National Priorities
List (NPL). The  most common current
treatment of lead contaminated wastes at
Superfund  sites  is immobilization, either
onsite or in a landfill. Remedial approaches
involving recovery  of lead are often pre-
ferred over immobilization, which wastes
usable lead. One such remedial approach
is the use of  secondary lead smelters for
recovery.
  The objective of this project was to de-
termine the technical and economical fea-
sibility of processing select lead-containing
wastes at secondary smelters. Five types
of waste materials were processed a single
secondary smelter in different tests. The
materials tested include material from three
Superfund sites  (the  Tonolli  site in
Nesquehoning, PA; the Hebelka  site in
Weisenburg County, PA;  and the NL In-
dustries site in Pedricktown,  NJ) and  two
other  sources (demolition  material   and
abrasive bridge blasting material). The re-
port summarized here presents the activi-
ties conducted, the experiments performed,
and the results obtained.

Process Description
  The  overall  process for the project in-
volves acquiring the waste material, trans-
porting it to a  secondary smelter, blending
it with  typical feeds, and smelting  it to
reclaim usable lead. A schematic of  this
process is  shown  in Figure  1, and  the
individual steps are described in more de-
tail  below.

Material Acquisition,
Preprocessing, and
Transportation
  The  first step  in  reclaiming lead from
Superfund wastes is acquiring and trans-
porting the  material to one smelter. Gen-
erally,  this  involves  excavation or
collection,  pre-processing, and transport
to the smelter. The lead-containing waste
                                                 Transport of material
                                             'CO

                                  Rocks, soils, debris
                                                          Mixing
                    Slag to
                   disposal
                                     Smelter
           Typical
         smelter feed
Figure 1. Schematic of reclamation process.


material is typically excavated from lead-
acid battery Superfund sites. Materials may
be collected from other sources, such as
bridge blasting or demolition operations.
  Some materials often require some type
of processing before entering the furnace.
Preprocessing includes  screening to  re-
move soil, large stones, or non-contami-
nated debris. Soil cannot be processed
through a secondary smelter. Larger de-
bris (>12  in.) is  also removed because
large  material tends to  remain unburnt in
reverberatory furnaces. This causes slug-
gish performance and slows productivity
by the reverberatory furnaces. Preprocess-
ing  can be  done at the  site  or at  the
smelter, depending on which is more cost
efficient.

Blending  with Typical Furnace
Feeds
  Once the  material arrives at the  sec-
ondary  lead smelter, it is blended  with
typical feed before processing through the
smelter's reverberatory and blast furnaces.
This mixing prevents problems associated
with the layering of the test material in the
furnaces. Typical  blend ratios range from
10% to 50% by  weight, and are deter-
mined based on treatability tests and other
factors,  such as lead, sulfur, iron, or ash
content.

Smelting Process
  As part of  normal secondary lead smelt-
ing operations, spent  batteries received at
the  smelter  are crushed to release  the
sulfuric acid  and then processed through
a sink/float system to separate the battery
cases. Dual  reverberatory furnaces at the
smelter  are  charged with material from
the sink/float system as well as other lead-
containing  material. These furnaces are
fueled with natural gas and  oxygen. Re-
verberatory furnaces are tapped for slag,
which typically contains 60%  to 70% lead,
and a soft (pure) lead product.
  Dual  blast furnaces  are charged with
the slag generated from the reverberatory
furnaces as well as other lead-containing
materials. These  furnaces are fueled by
coke and oxygen-enriched air. Iron  and
limestone are added as fluxing agents to
enhance furnace production. The blast fur-
naces are tapped continuously to remove
lead and intermittently to remove the slag.
The blast slag, which contains primarily
silica and iron oxides, is transported to an
offsite landfill for disposal.
  Lead  produced in the blast and  rever-
beratory furnaces is transferred to the re-
fining process where additional metals are
added to make specific lead alloys. The
lead is then pumped to the casting opera-
tions where it is molded into ingots for use
in the manufacture of new lead-acid bat-
teries.

Test Materials
  Materials from three Superfund sites as
well as  two additional  sets  of lead-con-
taining materials  were  processed during
this project. Table 1 presents a summary
of  the materials tested and  the evalua-
tions.  A short  description of  each  of the
five evaluations follows the table. The feed
rates are presented  as weight ratios of
test material to total furnace feed.

Tonolli Superfund Site
  The Tonolli site was a battery breaking
and   smelting   facility   located   in
Nesquehoning,  PA. Piles of  ebonite rub-
ber and  polypropylene battery case pieces

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Table 1.  Summary of Demonstration Sites
     Test Parameter
   Tonolli Site
                   Demolition Waste
                    NL Industries site
                        Pen n DOT
Site Type
Integrated battery
breaker, smelter,
and lead refiner
Automobile junk
and salvage yard
Not applicable
Integrated battery
breaker, smelter,
and refiner with
onsite landfill
Bridge blasting
operation to
remove lead paint
site landfill
Length of Test
Material Type
5 days
Rubber and plastic
battery cases
1 day
Rubber and plastic
battery cases with
some soil
2 days


Demolition debris
coated with lead
paint
Preliminary: 4 days
Full: 3 months

Lead slag, debris,
dross, ingots; bat-
tery case pieces,
baghouse bags,
pallets, cans
1 day
Iron shot bridge
blasting material
Amount
Processed
Percent Test
Material in Feed
                       84 tons
                        10%
                      8 tons
                       17%
                                                                 4 tons
                   5%
                    Preliminary test:
                    370 tons
                    Full-scale test:
                    1200 tons

                    20% to 50%
                                                           6 tons
                    13%
Lead Concentration
Preprocessing
Difficulties
Encountered
3.5%
None
Attempted to
process in reverb,
but material was
too large
14.7%
Reduced to less
than 1/4 in. in a
hammermill
None
1%
Reduced in size
with a pallet
shredder
Initial feed ratio
was too high
Preliminary: 57%
Full: 30% to 50%
Large pieces re-
moved for process-
ing in the blast
furnace
Reverb could not
process 100%
waste material
3.2%
None
Material was too
moist to process in
reverb furnace
were  tested, without any preprocessing.
The material had an  average lead con-
centration of 3.5%. Approximately 84 tons
of material  were fed  at a ratio of 10%
through a reverberatory and blast furnace.
The material was too large to be readily
processed in the reverberatory furnace but
was successfully processed in the blast
furnace.

Hebelka Superfund Site
  The Hebelka site was a former automo-
bile junk and  salvage yard  located  in
Weisenburg Township, PA. The site con-
tained battery case debris mixed with some
soil that had an average lead  concentra-
tion of  14.7%. Approximately 20  yd3  of
material were transported to the smelter.
This material was first  reduced in size  to
less than 1/4-in. with  a hammermill.  The
material was successfully fed to one  of
the dual reverberatory furnaces at  a feed
ratio of 17%.

Demolition Waste
  The demolition waste consisted  mainly
of wood coated with lead based paint and
                   had a lead concentration of between 0.5%
                   and 1% The test material was shredded
                   in a pallet shredder before it was smelted.
                   The  demolition  debris was processed
                   through both reverberatory  furnaces at
                   feed ratio of 10% test material, by weight.
                   At this weight ratio the  test material com-
                   prised  50% of the volume fed to the fur-
                   naces. This high volumetric  ratio caused
                   malfunctions in the furnaces, so the feed
                   ratio was reduced to 5%, at which point
                   the material was successfully fed.

                   NL Industries Superfund Site
                     The NL Industries site in  Pedricktown,
                   NJ,  was an integrated battery breaking,
                   smelting, and refining facility with its own
                   onsite landfill. There was a wide variety of
                   materials at the  site including lead slag,
                   dross,  debris,  ingots,  hard heads  (large
                   chunks of metallic lead), battery case de-
                   bris, baghouse  bags,  and  contaminated
                   pallets and  iron cans. The evaluation was
                   conducted in  two parts: a preliminary in-
                   vestigation  and a full-scale investigation.
                     During the preliminary investigation, ap-
                   proximately 370  tons  of  all  types of the
                                       above materials were processed. Analy-
                                       ses revealed an average lead concentra-
                                       tion of 57%; however, the materials ranged
                                       in  concentration  from 7% to 69% lead.
                                       The larger pieces of debris were removed
                                       and processed through  a blast furnace;
                                       while the bulk of the material was fed into
                                       a reverberatory furnace at feed ratios of
                                       up to 100%. The feed was sufficiently
                                       dense to cause breakdowns in the rever-
                                       beratory furnace conveyor feed  system,
                                       so the feed ratio was reduced to 50% test
                                       material, by weight.
                                         During the full scale operation, approxi-
                                       mately 1200 tons of material were trans-
                                       ported to the smelter over a three month
                                       period.  During the first  two months  the
                                       test material, which contained approxi-
                                       mately 45% by weight lead, was processed
                                       in  the  reverberatory furnace,  at a feed
                                       ratio of 20% to 30%. The ratio was limited
                                       because of  high amounts of calcium in
                                       the material. The high calcium concentra-
                                       tion slowed the operation of the furnaces.
                                       During the last month of the evaluation,
                                       the test material consisted mainly of larger
                                       pieces of slag and debris with an average

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lead concentration of 30%. This material
was charged to one  of the blast furnaces
at a feed ratio of approximately 30%.

Pennsylvania Department of
Transportation
   The Pennsylvania Department of Trans-
portation  (PennDOT) used  an iron-shot
abrasive blasting material to remove lead-
based paint from a bridge in Belle Vernon,
PA. Sixteen  55-gal  steel drums of this
material, containing  an  average of  3.2%
lead, were processed at the smelter. The
material contained too much moisture  to
be incorporated into the reverberatory feed.
The test material, including the drum, was
charged directly to a blast furnace  at a
feed ratio of approximately  13%, by weight.
The bridge blasting material was primarily
iron (60%) with  5% calcium and 5%  to
10% misture content.

Test Procedures
   Test material was charged to either the
reverberatory furnaces or  blast furnaces,
depending primarily  on the  size of the
material, but also on other factors such as
lead content and percent ash. Project per-
sonnel collected samples and data to as-
sess the furnace performance, characterize
the input  material, and characterize the
furnace outputs. Table  2  shows the pa-
rameters  that were  measured and  how
they were obtained.  The input material
parameters were characterized to  provide
information related to the feed, so that
comparisons  of  the  effects  of different
feeds could be made. The furnace perfor-
mance parameters, such  as  oxygen us-
age, fuel usage, furnace feed  rates,  etc.,
provided important furnace operation in-
formation while the experiments were con-
ducted,  principally indicating  when
production levels were falling or materials
were clogging in the furnace. The output
parameters were the  most  important mea-
surements of furnace performance, includ-
ing production rates  and quality, as well
as residuals generation.
  The data generated from measurements
and sample analyses were used to  com-
pare  the  performances  of the test  and
control furnaces. The amount of  lead  in
each product is useful in making a mass
balance for the lead. Other parameters,
such as oxygen, air, and fuel, are useful
in determining the cost for processing the
test material.

Results
  In general, the study demonstrated that
various materials may  be processed  in
secondary lead smelters  with relatively few
effects on  overall  furnace performance.
 Table 2. Input, Output, and Operating Parameters
    Input Material
   Characterization
   Furnace Performance
       Parameters
     Furnace Output
       Parameters
total lead (S)

sulfur (S)

silica (S)

calcium (S)

moisture content (S)

density (M)

particle size distribution (M)

BTU value (S)
test material in the feed (M)

air flow (M)

% oxygen enrichment (M)

fuel usage (M)

lead inputs (S)

iron inputs (S)

% test material in feed (M)
lead production rates (M)

slag production rates (M)

slag viscosity (Of

% lead in the slag (S)

% sulfur in the slag (S)

back pressure (M)

sulfur dioxide emissions (M)

calcium sulfate sludge (S)
 *(S)=Sample  (M)=Measurement   (O)=Operator Observation
The most significant effects were caused
by processing materials in a furnace with-
out properly  preprocessing it  or  by  pro-
cessing too much material at one time.
For  example, the Tonolli feed was too
large to  be processed effectively in the
dual reverberatory furnaces. This caused
the furnace production to slow down sig-
nificantly. Later, the same type of material
from  the Hebelka site was successfully
processed  in the reverberatory furnaces
after it had been shredded in a hammermill
to a particle size  of less than 1/4-in. The
NL Industries site  material was initially
unsuccessfully processed at a 100% feed
ratio  because it was too dense  for the
feed system.  When the ratio of test mate-
rial to total feed was lowered to 50% the
material  was  processed  with  few prob-
lems.

Feed Ratios
  The normal feed-to-waste ratio for these
materials was one of the parameters tested
during this  study. Based  on furnace per-
formance and operations  results,  it was
possible to  determine whether the furnace
performed successfully or unsuccessfully
at any given  feed ratio. A test is  consid-
ered to be unsuccessful if the feed ratio of
test material has to be lowered, or discon-
tinued altogether.
  Test results show that  the  successful
mix ratios are strongly a function of the
percentage of lead in the waste material.
Figure 2 shows the successful feed ratios,
             plotted against the percentage of lead in
             the waste material (i.e., before blending
             with normal feed). The results are nearly
             linear from streams containing 3% lead to
             those containing  60% lead.  This delin-
             eates the region marked "successful" on
             the figure. When  the feed ratios versus
             lead concentration for unsuccessful runs
             are plotted, a second region (the "unsuc-
             cessful" area) emerges.  Finally,  a third
             region, in which no tests were performed,
             is also marked on the figure. No test feed
             with more than  60%  lead was fed to the
             furnaces, so the regions in the range above
             60% lead cannot be determined from the
             experimental results.

             Reclamation Efficiency
               In  determining whether the process is
             suitable for reclamation of lead,  it is im-
             portant to determine  whether the smelter
             actually reclaimed the lead in the test ma-
             terial. Unfortunately,  there is no  way to
             accurately measure the extent of recla-
             mation because the  test material has to
             be mixed with typical  feed.  Based on con-
             servative assumptions and furnace output
             parameters such  as initial lead  content
             and  percent  ash, CHMR  developed a
             method to estimate  the minimum recla-
             mation efficiency.  This method indicated
             that lead was reclaimed from all test ma-
             terials over a range  of efficiencies,  from
             an estimated 70% for the abrasive blast-
             ing  material  to  99.5% for NL Industries
             material.

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                       100%
                     o"
                        80%
                     "§  60%

                     .c


                     I  40%

                     I
                     w
                     ^  20%
                         0%
                                                                                         X-*
                                          \Unsuccessful
                                                                                x*
                             *'
                           0%
              10%
                                                                                      50%
         20%        30%         40%
              % Lead in test material
Successful experiment      A  Unsuccessful experiment
                                                                       60%
Figure 2.  Percent lead in test material versus feed ratio.
Economics
  CHMR used the experimental data and
other information to develop an economic
model  based on the following costs and
values of recovered materials:
  • Excavation costs
  • Transportation costs
  • Smelter processing base cost
  • Additional production costs associated
    with storage  and  handling of an
    atypical material at the smelter
  • Additional disposal costs
  • Lead recovery
  • Reduction  of  iron, coke,  or other
    furnace feeds.
  With this model,  the costs in the follow-
ing table have been estimated for the ma-
terials  used  in this evaluation. Table  3
includes two costs, the first is based on  a
conservative  market value  for lead ($6507
                ton) and the second on a more plausible
                long-term value for lead ($750/ton). Note
                the  relationship between  the costs  and
                some of the material characteristics. Lower
                lead content causes an increase in costs,
                whereas ash content and  distance from
                the smelter have a lesser effect.


                Conclusions
                  The conclusions drawn from the study
                are:
                  •  Lead was successfully reclaimed from
                     a  variety of materials found  at many
                     Superfund sites, including battery case
                     pieces, slag, dross, lead debris, spent
                     abrasive material, and  demolition
                     material contaminated with lead paint.
                     The  lead  concentration  in  these
                     materials ranged from 1 % to 45%
                                            • The economics of  reclaiming lead
                                              depend on lead concentration, market
                                              price for lead, distance  from the
                                              smelter, percent of test material that
                                              becomes incorporated into the final
                                              slag, iron content, BTU value of the
                                              test material, and sulfur content.
                                            • The cost for recovering lead from the
                                              five sites selected for this project,
                                              based on a conservative market price
                                              for lead ($650/ton), ranged between
                                              $80 and $374/ton.
                                            Overall, CHMR concludes that second-
                                          ary lead smelters provide a viable alterna-
                                          tive to  stabilization and disposal  for the
                                          treatment of wastes  found at  battery
                                          breaker and some Superfund sites. This
                                          process also makes it possible to recycle
                                          and reuse lead which is a useful resource.
Table 3. Estimated Cost of Remediating Sites
       Site
P=$650/ton
     P=$750/ton
Distance(miles)
%Ash
                                                                                                              % Lead
Tonolli
Hebelka
Demolition Material
NL Industries
PennDOT
$228
174
374
80
231
$224
160
373
35
228
40
75
100
300
250
20
30
4
65
70
3.5
14.7
1.0
45.0
3.2

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Stephen W. Paff and Brian E. Bosilovich are with the Center for Hazardous
  Materials Research.
Laurel Staley is the EPA Project Officer (see  below).
The complete report, entitled "Emerging Technology Report: Reclamation of Lead
  from Superfund Waste Material Using Secondary Lead Smelters," (Order No.
  PB95-199022; Cost: $19.50, subject to change)  will be available only from:
        National Technical Information Service
        5285 Port Royal Road
        Springfield, VA 22161
        Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
        Risk Reduction Engineering Laboratory
        U.S. Environmental Protection Agency
        Cincinnati, OH 45268
  United States
  Environmental Protection Agency
  Center for Environmental Research Information
  Cincinnati, OH 45268

  Official Business
  Penalty for Private Use
  $300
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POSTAGE & FEES PAID
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   PERMIT No. G-35
  EPA/540/SR-95/504

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