-------
chemical conditions involved in the experiments. However, it is readily apparent that the most
effective preleaching agent is the strong aqueous oxidizing acid, nitric acid.
Neither a weak base (sodium carbonate) nor water alone proved to be very effective at remov-
ing iron or most other trace elements from the refuse samples. Ferric ion, added as a leaching
agent in the form of ferric sulfate, proved to be a more effective agent for preleaching the refuse
samples. Refluxing of ferric (0.25JV) sulfate solution in the presence of crushed refuse material for
1 day (Sample No. 12) resulted in the removal of close to 30% of the total iron from the sample, as
well as considerable amounts of several other key trace elements. A review of the literature on
coal desulfurization with ferric ion' suggests that much greater pyrite (iron) removal efficiencies
can be obtained from the refuse samples by increasing the ferric sulfate concentrations in the
leaching solutions to about IN (Table IX). Finally, by far the most effective preleaching agent for
removing iron and the several other environmentally important trace elements considered in this
investigation was nitric acid solution (Sample No. 22). More than 90% of the total iron and about
50% or more of the total cobalt, copper, manganese, nickel, and zinc were removed by a 2-day
treatment of the refuse material with 8N nitric acid.
Our research on preleaching of coal refuse materials to remove labile trace elements, the acid-
forming mineral constituents, or both is still at a rather early stage, and we do not yet possess suf-
ficient technical information on this potential control technology option to conduct a solid
economic assessment of it. In a properly designed control technology scheme in which the
leaching agent is recycled, the use of nitric acid, for example, to preleach coal refuse could prove
to be economically viable, especially considering the strong possibility for resource recovery of-
fered by this technique. Although more experiments are needed before a final assessment can be
made, the usefulness of ferric ion solutions to preleach coal refuse materials appears marginal
because of the relatively low extractabilities achieved for many of the elements of greatest en-
vironmental concern.
Addition of Neutralizing Agents to Discarded Refuse Materials
Several methods are being considered to treat coal refuse during disposal to prevent the release
of trace contaminants during subsequent waste dump weathering or leaching by surface or
TABLE IX
EFFECTIVENESS OF FERRIC SULFATE TREATMENT ON
IRON REMOVAL FROM COAL AND COAL WASTE
Percentage of Iron (Pyrite) Removed
Coal Waste Coal
Fe+++ Level (N) 0 0.05 0.25 0 0.4 O.i)
92°C/24ha 4" 2" 18"
H)0°C/6h ~lc 33-43" 50-64d
•See text for experiment description.
"Observed value is 10% higher, but 10% is also soluble in water at
•20°C!
cRef. 1, p. 176.
"Ref. l.p.67.
15
-------
ground water. These include codisposal of the refuse material with neutralizing agents or trace
element adsorbents and the application of watertight sealants to all or parts of the waste dump
mass. Especially promising among these techniques is the codisposal of high-sulfur refuse with
lime or limestone to neutralize acid drainage in situ and retain aqueous contaminants within the
refuse disposal site.
One of the major conclusions from our earlier studies of the environmental behavior of coal
refuse materials concerned the importance of pH in controlling trace element releases during
refuse leaching. In all instances when leachate pH was maintained at or near the neutral point,
only minimal amounts of trace elements weresolubilix.edby theleachates.Conversely, when ox-
idative degradation of the pyritic materials in the refuse caused leachate acidities to build up,
substantial quantities of such environmentally troublesome elements as aluminum, cobalt, cop-
per, iron, manganese, and nickel were lixiviated. by the acid leachates.''4 This marked
dependence of trace element contamination on leachate pH suggested that a potentially fruitful
means of preventing trace element releases from discarded refuse materials might be the addition
of neutralizing agents to the refuse before disposal to negate leachate acidity as soon as it is
formed.
Column leaching experiments that used mixtures of crushed limestone and high-sulfur refuse
were conducted to test the effectiveness of this in situ neutralization concept and also to examine
what effect the location of limestone application had on the results. The refuse was from Illinois
Basin Plant B. This refuse contains relatively large amounts of pyrite and marcasite but no
detectable calcite. This combination represents a worst-case example of acid-forming potential,
and in fact, our earlier studies showed that the leachates formed by passing water through a
packed column of this material were not only highly acidic but were also highly contaminated
with trace elements. Interestingly, the limestone itself contain" troublesome amounts of several
environmentally sensitive elements including copper, iron, lead, manganese, and zinc. The
elemental analysis of the limestone used is given in Table X.
The combinations of refuse and limestone incorporated into the leaching studies are listed in
Table XI. Crushed or powdered limestone was combined with the refuse or placed in the column
in three different geometric arrangements: at the inlet (simulating a limestone layer placed on
top of a refuse pile), at the outlet (simulating refuse disposed on top of a limestone layer), and
limestone and refuse intermixed. These column leaching experiments were conducted by passing
distilled water through the column packed with the refuse/limestone mixtures at a rate of 0.5
mi/min. Periodically, samples of leachate were collected at the column outlet, and pH, total dis-
solved solids, and trace element compositions were determined. Leachate flow was interrupted
once during several of the experiments (after a little more than 10 t had been eluted), and dry air
. was passed through the packed columns for three weeks before recommencing leachate flow. This
was done to explore contaminant regeneration in the refuse/limestone mixtures.
The overall effect of the various limestone additions to the refuse columns is illustrated by the
behavior of the leachate pH shown in Fig. la. In general, it is seen that adding limestone to the
acid refuse material was only partially successful in controlling leachate acidity. The pH values
of the refuse/limestone leachates for experiments GL-14, 15, and 17 (where the limestone was in-
termixed with the refuse or placed at the column outlet) are higher throughout than for refuse
alone (GL-12). However, even in the best instance it took about 5 £ of water for 1300 g of refuse to
reach neutrality. Placing the limestone layer on the inlet side of the refuse column (GL-16)
resulted in no decrease in leachate acidity over the control system. This undoubtedly is due to the
slow rate of dissolution of limestone in neutral solution (water).
The effects of the various limestone additions on the TDS composition of the refuse leachates
are depicted in Fig. Ib. There is very little difference among the TDS values for any of the
leachates. This most likely results from the fortuitous balancing of the constituents removed (by
elevating the leachate pH) with those added by limestone dissolution (see Fig. la).
16
-------
TABLE X
ANALYSES OF JEMEZ LIMESTONE USED IN
NEUTRALIZATION CONTROL
TECHNOLOGY EXPERIMENTS
Element
Level
(Mg/g)
Level
Element (j/g/g)
Na
Mg
Al
SiOj
P
S
K
Ca
Sc
Cr
Mn
Fe
Cu
Zn
Ga
As
Br
120
0.34
0.41
3.4
220
<0.1
790
42
0.1
18
560
0.26
19
19
<0.5
0.6
0.3
Rb
Ag
Cd
Sb
La
Ce
Sm
Eu
Yb
Lu
Hf
Ta
W
Hg
Pb
Th
U
<20
0.3
0.6
<0.5
0.4
<0.8
<0.2
<0.3
<0.2
<0.5
0.1
82
<0.2
1.2
TABLE XI
DESCRIPTION OF DYNAMIC LEACHING STUDIES OF
HIGH-SULFUR REFUSE/LIMESTONE MIXTURES
Experiment No. Limestone Location
GL-12 (None-control)
GL-14 Intermixed
GL-15
GL-16
GL-17
Layered at outlet
Layered at inlet
Layered at outlet
Sample8
1500 g refuse (-3/8 in.)
1300 g refuse (-3/8 in.)
220 g limestone (-3/8 in.)
1300 g refuse (-3/8 in.)
229 g limestone (-3/8 in.)
1300 g refuse (-3/8 in.)
221 g limestone (-3/8 in.)
1300 g refuse (-3/8 in.)
220 g limestone (-20 mesh)
•Illinois Basin Plant B refuse used throughout.
17
-------
LEGEW
o = GL-12
GL-14
(a)
(b)
6.0 9.0 12.0 15.0
VOLUME (liters)
W.O
21.0
24.C
Fig. 1.
Leachate pH and TDS versus leachate volume for column leaching study of limestone/refuse
mixtures.
18
-------
The trace element compositions for the leachates from the refuse/limestone mixtures were fol-
lowed throughout the experiment (Appendix C). Some elements, such as aluminum, chromium,
potassium, scandium, and vanadium, were apparently sensitive to leachate pH and, hence,
tended to precipitate from the refuse/limestone mixtures. (The exception was GL-16 where the
I>H remained low.) Other elements, including cobalt, copper, iron (probably in ferrous slale).
manganese, and zinc were not apparently so highly pH-dependent in these mixtures; therefore,
there was little effect of the limestone addition on the leachate concentrations of these elements.
Unfortunately, most of the elements that we have identified as being of greatest environmental
concern (listed in Ref. 3) fall into the latter category.
In summary, these experiments revealed that crushed limestone (-3/8 in.) is only moderately
effective in controlling the acidity of refuse leachates, largely, we believe, because of the slow rate
of dissolution of the limestone under the conditions of the experiments. During the year, we have
extended these studies to include, as additives, more finely powdered limestone and limestone
I hut bas been slurry-mixed with the refuse. Both should be more effective (in a kinetic sense)
than the coarser dry-mixed limestone at controlling leachate pH and, indirectly, trace element
composition. Preliminary data from these later experiments, which will be tabulated and discus-
sed in future reports, reveal that both the fineness of the limestone and the manner in which it is
mixed with the refuse are indeed very important variables in determining the effectiveness of
limestone at controlling refuse leachate pH and trace element composition.
Our efforts involving the additions of powdered lime to high-sulfur refuse materials to control
leachate pH and trace element content proved to be very fruitful. For these experiments,
powdered lime in varying amounts (3 to 50 g) was slurried in 150 mi of distilled water with 530 g
of -3/8-in., high-sulfur coal refuse from Illinois Basin Plant B. The resultant mixture was subse-
quently dried in air at50°C and recrushed to -3/8-in. particles. Four different lime concentrations
were used. The experiments are identified as follows.
Lime Level
Experiment No. (wt%)
0
0.5
1.5
:j
10
Column leaching experiments were conducted with about 500 g of each of the above samples to
determine the effects of the lime additions. The refuse mixtures were packed into pyrex columns
40 cm long by 5 cm in diameter and subsequently were leached with distilled water at a flow rate
of 0.5 mi/min until more than 4 i of water had been passed through the refuse beds. Leachate
flow was interrupted once during the experiment at the 4.2-.E point, and dry air was passed
through the column for 2 wk to test the acid-regeneration potential of the refuse/lime mixtures.
Tables and plots of leaching data, pH, and trace element analyses for these experiments are com-
piled in Appendix D.
Figure 2 shows pH and total dissolved solids behavior as a function of lime addition. A consis-
tent pattern of the effects of the lime additions emerges from these data. The add it ions of 0.5 and
1.5 wt% lime to the acid refuse had only a small influence on leachate pH and trace element con-
centration because the acid neutralization provided by these amounts of lime was overwhelmed
by the acid present in the refuse. The additions of 3 and 10 wt% of lime, on the other hand, did in-
deed effectively counteract the acid properties of the refuse. The pH values of the leachates for
these mixtures were higher, TDS values were relatively low, and the trace element concentrations
were depressed.
CTW
CTW
CTW
CTW
CTW
'-11-1 (control)
'-11-2
'- 1 1 -:)
'-11-4
'-11-5
19
-------
LEGEND
"CTWT11-1
=»CTWT11-2
» = CTWT11-5
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0
VOLUME (liters)
(a)
(b)
Fig. 2.
Leachate pH and TDS versus leachate volume for column leaching study of lime/refuse mix-
tures.
20
-------
The mixture containing 3 wt% lime was especially interesting because a leachate pH of 7 was
maintained for nearly the entire duration of the continuous part of the leaching experiment (until
4.2 t had been passed through the column). The TDS values for this refuse/lime combination
were also very respectable (ranging downward from about 0.6 wt%), especially considering that
the dissolution of the lime itself adds substantially to the dissolved solids content of the solution.
By the end of the continuous part of the leaching experiment, concentrations of troublesome
trace elements, especially iron and manganese, had been reduced to environmentally acceptable
levels. Regeneration of this refuse/lime mixture with air did tend to lower the leachate pH and to
elevate the trace element concentrations. However, we did not continue the study long enough
after the regeneration point to determine subsequent behavior.
The codisposal of alkaline agents, such as lime, with acidic coal refuse materials does appear to
be an attractive option for controlling trace element contamination of disposal area drainages.
The technique is only moderately costly ($0.50 to $1.00 per ton of cleaned coal, see Appendix B)
and appears to be a highly effective means of preventing the release of a contaminated drainage
from coal refuse dumps. The technology for mixing alkaline agents with coal refuse materials
should be relatively simple and is immediately effective.
There are also a few questionable aspects connected with the use of alkaline additives for coal
refuse materials. One uncertainty involves the long-term effectiveness or permanency of the
method. Also, the durability and immobility of the alkaline additives over long geologic periods
must be demonstrated. Another potential drawback of codisposing alkaline additives with high-
sulfur coal refuse materials concerns the RCRA classification of the resulting refuse/additive
mixtures. It is not at all clear whether such a mixture would be classified as hazardous or
nonhazardous. As pointed out earlier, a hazardous RCRA designation could be quite costly for
the disposal site operator. Another somewhat negative aspect of refuse codisposal with alkaline
agents (as compared to refuse calcining, for example) is its low potential for by-product recovery.
The lack of such potential, of course, negates the possibility of offsetting environmental costs
with recovered product value.
Addition of Sorbents or Attenuating Agents to Discarded Refuse Materials
The codisposal of attenuating agents or sorbents, other than lime or limestone, with acidic coal
refuse materials also has great potential for reducing or abating trace element contamination of
disposal site drainage. Many natural materials, such as certain types of clays and soils, and many
industrial wastes, such as fly ash or alkaline sludges, may have considerable capacity to at-
tenuate contaminated refuse drainage, and often these materials are available in large and acces-
sible quantities near refuse disposal sites. Some of our research during the year was directed at
assessing the potential of various attenuating agents for reducing the trace element and acid
compositions of coal refuse leachates and thus at revealing the possible effectiveness of this class
of agents as refuse dump additives.
Our initial investigation into this area included a series of natural and man-made materials
collected from various parts of the country. In one set of experiments, acidic coal refuse leachates
were equilibrated with eleven solid sorbent materials to evaluate their trace element attenuation
capacities. The solids used were
• CaCOj (standard)
• Acid mine drainage treatment sludge
• Bottom ash from a western power plant
• Precipitator ash (fly ash)
• Bottom slag from a midwestern plant burning western coal
• S03 scrubber sludge from a midwestern plant burning western coal
21
-------
• Alabama soil
• Illite clay
• Montmorillonite clay
• Kaolinite clay
• Sea sand (two replicates).
The experimental procedure consisted of shaking the solid with the coal refuse leachate* for
15 h, measuring the pH, and analyzing the filtrate for trace elements. Companion experiments in
which the solids were shaken with distilled water were carried out to evaluate the alkalinity of
the sorbent and to determine its water soluble components. The pH values of the filtrates from
the solid attenuating materials previously mixed with distilled water ranged from 5.8 (sea sand)
to 11.2 (precipitator ash). The pH values of the filtrates from the refuse leachate/solid mixture
ranged from 2.8 (sea sand) to 9.6 (precipitator ash). As a general rule, the higher the pH, the
lower the trace element concentrations. Total dissolved solids are not included in these discus-
sions because after equilibration, the soluble matter of some sorbent materials artificially
elevated the TDS values in the leachates.
The results of these experiments are discussed with reference to Tables XII and XIII. Table XII
has essentially all the data pertinent to the experiments, including the liquid/solid ratios, the
measured pH values, and the trace element concentrations. In general, Table XII is self ex-
planatory and points out the potential benefits of using some of the coal combustion by-products
and naturally occurring clays as a treatment for coal refuse drainages, even where the acid con-
tent of the drainage is quite high. Table XIII lists in a more qualitative manner, the performance
of the various sorbents with regard to leachate pH elevation and attenuation of the 13 trace ele-
ments that we have identified as being of greatest environmental concern in the Illinois Basin
coal refuse effluents. We have isolated different sections in Table Xin to draw attention to some
of the salient features.For example, because the solubilities of Fe+3 and Al"13 are highly depend-
ent on pl-l in acidic solutions, those sorbents that are most effective in elevating the pH are also
most effective in decreasing the concentrations of Fe+3 and AI+3.The results listed in Table XIII
are quite striking and demonstrate clearly that 7 of the 11 soi-bents tested are ell et -live in control-
ling the key leachate parameters.Cost analyses of various codisposal options, including lime and
fly ash with and without limestone modification, are included in Appendix B (Table B-IV) and
are favorable for several options.
In another series of investigations, 14 subsurface soils from the Illinois Basin were tested to
determine the ability of these materials to reduce the trace element and acid concentrations in
contaminated coal refuse leachates. These soils represent a cross section of the types found in the
coal producing regions of the Basin. Soil properties ranged from noncalcareous to calcareous, un-
weathered to weathered, low to high clay content, and low to high cation-exchange capacities.
Only one soil had appreciable organic content.
The experimental procedure for this study involved a series of successive dilutions with each
soil type. First, a moderately contaminated coal refuse leachate was agitated for about 16 h using
a 5:1 leachate-.soil ratio (by weight) for each of the noncalcareous soils and a 10:1 leachate:soil
ratio for the calcareous soils (see Table XIV). The latter condition was chosen because of the ex-
pected higher acid-attenuating capacities of the calcareous soils. (This first set of leachate/soil
equilibrations is designated Leach Step 1 in Table XIV.) Fresh soil was then added to the
filtrates from the first leach step, and the mixtures were again agitated for a 16-h period (Leach
Step 2). This cycle of equilibration followed by fresh soil addition was carried out as many as five
times for some of the leachate/soil mixtures. This information, along with data on leachate pH
and trace elementcomposition, are shown in Table XIV. A qualitative assessment of the leachate
attenuating capacities of each of the soil types appears in Table XV.
*The coal refuse leachate had a pH of 2.6 and a strong yellow color, indicating that most of the Fe*1 had been converted
to Fe*1.
22
-------
TABLE XII
RESULTS OK EXPERIMENTS USING ELEVEN SOHBENTS FOR pH
CONTROL AND TRACK ELEMENT A'lTENUATION FOR AN
ILLINOIS BASIN HIGH-SULFUR COAL REFUSE LEACHATE
Element Levels Removed
Sample
0
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
24
Sorbent
AMI) Treatment
Sludge
Bottom Ash
Precipitator Ash
Illite
Montmorillonite
Kaolinite
Alabama Soil
CaCO.
Bottom Slag
SO, Scrubber
Sludi-e
Sea Sand
Sea Sand
Liquid/Sol PH
Liquid Ratio
Leachate
H,O
Leachate
H,0
Leachate
H,0
Leachate
H,0
Leachate
H.O
Leachate
H,O
Leachate
H,0
Leachate
H,O
Leachate
H,0
Leachate
H,0
Leachate
H,O
Leachale
H,0
Leachale
H.O
4
4
3
3
3
3
3
3
9
9
3
3
3
3
3
3
3
3
3
3
3
3
3
2.64
7.63
7.67
8.08
8.59
9.63
11.23
8.08
7.84
7.95
8.46
4.29
6.03
4.01
6.30
8.03
9.14
4.23
7.63
7.34
8.35
2.80
5.88
2.81
5.83
F
PPM
2.0
0.2
0.2
1.5
0.7
1.6
1.1
1.5
1.6
0.4
0.2
2.6
0.3
2.3
0.2
0.16
0.15
0.9
0.2
4.0
4.2
1.8
0.2
1.5
0.17
Na
PPM
108
82
5
150
36
163
49
145
22
770
106
6
90
5
102
11
102
2.5
125
25
95
95
Al
PPM
10
<0.5
<0.2
0.6
<0.2
<0.2
0.6
2
0.6
<0.5
7
21
13.5
0.4
10
<0.2
-------
TABLE XIII
COMPARISON OK CAPABILITIES OF ELEVEN SOKBENTS TO
ELEVATE pH AND TO ATTENUATE THIRTEEN TRACE ELEMENTS IN
ILLINOIS BASIN COAL REFUSE LEACHATES-
Sorbcnt pH
CaCO, EEE
AMD Treatment EEE
Sludge
Illite EEE
PrecipitatorAsh EEE
Montmorillonite EEE
Bottom Ash EEE
SO, Scrubber EEE
Sludge
Alabama Soil FF
Bottom Slag FF
Kaolinite FF
Sea Sand P
•EEE = > lOOx Reduction
GG = 10 to lOOx Reduction
FF = 3 to 10* Reduction
P = 0.5 to 3x Reduction
o = >2x Increase
Fe
EEE
EEE
EEE
EEE
EEE
EEE
EEE
GG
P
GG
P
Al Ni
EEE GG
EEE EEE
GG GG
GG GG
FF GG
EEE FF
EEE FF
P P
FF P
P P
P P
Mn
EEE
GG
GG
EEE
GG
P
P
o
P
o
P
Zn
EEE
GG
FF
GG
GG
GG
P
P
P
o
P
Co
GG
GG
GG
GG
GG
FF
P
P
P
P
P
Cr
P
GG
GG
0
GG
GG
FF
GG
GG
FF
P
Cu
FF
GG
GG
FF
FF
P
FF
P
P
0
o
F
GG
GG
P
P
GG
P
o
P
P
P
P
Cd Na
GG P
P P
GG P
GG P
FF o
FF P
0 P
P P
0 P
0 P
P P
K
P
P
o
P
P
P
o
P
P
P
P
Ca
P
o
o
o
FF
o
o
P
P
P
P
-------
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HX>
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1
2
3
3
4
6
1
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2
3
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1
3
3
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5
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5
10
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1.1
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7.9
01
7.6
A.6
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7.
G.4
7.4
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7.4
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J8
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7.3
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7.0
6.9
46
7.3
B I
6.9
7.4
HI
flj
8.3
e.e
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8ft
6.9
7.7
V
PPM
1.4
06
3.4
0.7
16
tin
OJ
1,4
1ft
16
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11 ti
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1.1
10
1.3
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06
04
07
06
0,4
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0.7
Al
PPM
DA
3
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-------
S)
Ov
TABLE XV
HATCH ATTENUATION OK TRACE ELEMENTS IN COAL REFUSE LEACHATES BY SOILS
Soil Parameters
Degree of Attenuation*
Soil Type
Till
Till
Till
Till
Loess
Till
Organic
Loess
Alluvium
Loess
Loess
Till
Alluvium
Loess
Soil No.
10
11
12
4
8
14
3
6
5
1
13
7
9
2
pH
8.2
8.2
8.2
8.2
8.2
8.5
8.1
8.1
8.3 '
7.6
8.0
7.9
7.7
5.6
COi(%)
15.1
13.4
9.2
8.6
8.3
7.7
6.8
5.8
1.6
0.7
0.4
0.3
0.2
0.0
CEC (meq/g)D
91
77
96
89
88
143
303
116
261
144
98
280
253
279
OM (%)c
0.4
0.9
0.2
0.9
0.3
0.2
7.3
0.4
0.7
0.3
0.2
0.3
0.6
0.5
pH Ko" Al Zn Ni Co Cr Cd Mn F Ca
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EEEE EEEE EEEE EEEE GG GG GG GG FF FF P
EEEE EEEE EEEE EEEE GG GG GG GG FF FF P
EEEE EEEE EEEE EEEE GG GG GG GG FF FF P
EEEE EEEE EEEE EEEE GG GG GG GG FF FF P
EEEE EEEE EEEE EEEE GG GG GG GG GG FF P
EEEE EEEE EEEE EEEE GG GG GG GG FF P P
EEEE EEEE EEEE EEEE GG GG GG GG FF FF P
EEEE EEEE EEEE EEEE GG GG GG GG FF FF P
EEEE EEEE GG GG GG FF - FF P o P
FF EEEE FF FF FF FF FF P P P P
FF EEEE GG FF GG FF - GG P P P
FF EEEE FF o FF FF P P P P P
P EEEE P P PFF-PPPP
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CC = lll-ll«l\ IMuitiun
KK = .1 Klx Krriiirlnm
I' = ll..V:lx KttUu-Imn
'• = >.'tx liuTtMS**
*<':il inn Kit-hull;;!1 Cn|Niril v.
rl)ri!iiiiii- Miilrriiil.
dlnm |irini;iritv in ferric >l;ilf.
-------
The data in Table XV are ordered according to the percentage of titratable carbonate in each
soil. According to the effectiveness scheme used in the table, all of the soils with >1.6% carbonate
content are rated as fair (FF) to excellent (EEEE) in attenuating the toxic elements present in
the leachate. These results show that many alkaline soils do have a significant capacity to reduce
the trace element and acid contents of refuse drainages. This attenuating capacity appears to
function mainly on the strengths of these soils in controlling leachate acidity. The additional
question concerning whether the cation-exchange capacity (CEC) of each soil type has any major
bearing on the capacity of that soil to attenuate leachate contamination is somewhat more dif-
ficult to answer based on the data that we have obtained thus far. It is significant, however, that
even those soils with essentially no acid-neutralizing capacity (Soils 2, 7, and 9) do attentuate
many of the leachate contaminants somewhat. This observation lends credence to the postulate
that both the alkalinity and ion-exchange capacity are important in determining the
contaminant-attenuating properties of soils.
Even though our work with soils as an environmental control medium for acidic, coal refuse
leachates is still in its early stages, it is already apparent that soils as a group (especially alkaline,
unweathered soils) have great potential for this purpose because of their abundance and
availability near coal refuse dumps. The results of our work this year were sufficiently encourag-
ing to suggest that a cost estimate for this form of environmental control technology be made. Us-
ing a locally available soil with a 5 wt% titratable alkalinity, we estimate the cost per ton of
cleaned coal to permanently treat highly acidic coal refuse matter (by intermixing with the
refuse) to be in the range of $0.80 to $1.30, depending on the potential acidity of the refuse (see
Appendix B, Table B-IV). These costs would, of course, be lower if some of the more highly
alkaline soils listed in Table XV were to be used and if the soils also had significant ion-exchange
capacity.
Future studies in this area will be aimed at quantifying both the total capacities and ion
specificities of various soils during the attenuation of coal refuse leachates. This will be done by
passing contaminated leachates through soil columns and by direct leaching of mixtures of
various soils and acid refuse materials. The more promising control options will be scaled up to
better duplicate field conditions.
Sealing Refuse From Air and Water
In view of the overwhelming evidence that isolating high-sulfur coal refuse from air and water
will prevent the formation of acids and thereby the release of trace elements into the environ-
ment, one area of control technology that we are addressing is that of sealing the refuse pile,
dump, or burial site to prevent the intrusion of air or water. The concept of sealing has overtones
in all aspects of coal waste (and other waste) disposal. Sealants can be used for existing refuse
piles and dumps and for near-surface and underground burial of wastes.
Various sealant, scenarios, with an emphasis on clays, soils, cnldte. and various cementing
agents (Portland and silicate cements and polymers) as sealing agents, are being considered, and
we have begun laboratory experiments to test some of our ideas. One of the first experiments in-
volved slurrying crushed coal refuse (-3/8 in.) with 5 wt% lime in water and neutralizing the
alkaline mixture by bubbling C02 through it until the pH was reduced to 7. This had the effect of
coating the coal waste particles in the slurry with limestone by the reaction CaO + COS = CaC08.
The effectiveness of the seal was tested by drying the particles, performing a column leaching test
on them, and measuring the pH and trace element compositions of the resulting leachates. The
results of this experiment are given in Table XVI. These data reveal that this method of coating
the refuse particles with a limestone film was very successful in controlling both the acid and
trace element compositions of the refuse leachates. The pH values of the emerging leachates were
maintained between 7.2 and 7.9 for the entire experiment, and the criteria pollutants (iron and
27
-------
manganese) were controlled within acceptable limits. The other elements reported in Table XVI
are greatly reduced in concentration as compared to their levels in leachates from untreated
refuse materials. (See control sample in Table D-II.)
Calcium carbonate coating of acid refuse materials is a promising method for controlling con-
tamination of aqueous drainages. In practice a local self-contained unit could be designed to use
this principle. The needed lime could be supplied from a small kiln, and the CO, and heat for
drying the coated particles could also be produced by the kiln. Furthermore, coal fines or mid-
dlings from thecleaningplantcouldconceivably be used as the principal fuel for the kiln.The ad-
vantages of this combination in savings of energy and expense could be considerable.
In other work in the area, we have begun to investigate the feasibility of producing a concrete-
like aggregate from mixtures of Portland cement and crushed acid coal refuse. The resulting
product should be a marked improvement over the untreated refuse aggregate, including reduced
permeability, acid-generating potential, and increased structural integrity. Several small
cylinders (3.1 cm in diameter and 2.5 cm long) were produced using various proportions of mortar
and -20-mesh refuse. Static leaching tests of several of these cylinders with distilled water for
periods of up to 34 days revealed that the structure of the cylinders was not appreciably degraded
by contact with water. Furthermore, the pH of the leachates ranged from about 9 to 11.5, sug-
gesting that trace element teachability of the refuse would be substantially reduced.
One problem with using commercial cements to produce refuse aggregates is the high cost of
structural-grade cement. Therefore, we will begin to explore the possibility of producing cements
TABLE XVI
RKSULTS FROM A COLUMN LEACHING EXPERIMENT WITH
CALCITE-COATED ILLINOIS BASIN COAL REFUSE
Sample No." 1 2 4 11 17
Vol (I)
pH
TDS (%)
F
Na
Al
K
Ca
Cr (Mg/£)
Mn
Fe
Co
Ni
Cu
Zn
Cd (ng/t)
0.100
7.4
0.84
0.3
7
<0.5
7
900
<0.5
0.7
5
0.13
0.3
0.1
0.07
2
0.201
7.2
0.63
0.4
6
<0.5
8
870
1
0.5
2
0.12
0.2
0.1
0.07
1
0.697
7.9
0.34
0.3
2.5
<0.5
4
630
<0.5
0.2
0.4
0.06
0.2
<0.1
0.03
0.4
2.309
7.7
0.27
0.3
1
<0.5
2
540
<0.5
0.1
<0.3
0.05
0.1
<0.1
0.01
0.2
3.326
7.7
0.22
0.4
1
<0.5
1
480
<0.5
0.07
<0.3
<0.05
<0.07
<0.1
<0.01
0.3
•Kxperimumal conditions: 500 K of calcile-coated. -.'i/S-in. coal
refuse material was packed into a 5-cm-diam bv 40-cm-loiif! class
column. Distilled water was passed upward through the column
at a rale of 0.5 inl/inin. Kxcept where noted, element concentra-
tions are
28
-------
or cementitious materials from the refuse itself. This could involve the calcining of powdered
refuse and limestone mixtures or perhaps the treatment of the refuse to produce a pozzuolanic
material.
Subtask 1.2—Assess Technology to Control or Reduce Trace Element Contamination of
Refuse Dump Drainages
The purpose of this subtask is to identify environmental controls to reduce or attenuate un-
desirable trace elements in the acidic drainages from coal refuse dumps. Our attention in this
area has been given to pollution abatement techniques that have proved effective in treating
acidic waste waters with compositions similar to coal refuse drainage. These techniques include
alkaline neutralization, ion exchange, reverse osmosis, and permanganate oxidation. We have
also initiated studies on the effectiveness of using a variety of sorbents, such as clays, soils, and
solid coal combustion by-products, on high-sulfur coal refuse Icachales. (Tin1 latter research was
discussed above in Subtask 1.1.) In these studies we are continuing to give greatest emphasis to
the control of the dozen or so trace elements that we have identified in our previous studies as be-
ing of greatest concern in the drainages from Illinois Basin coal refuse.
During the year, we were able to initiate a small number of cooperative projects with commer-
cial organizations having expertise in water treatment. We supplied the contaminated leachates
and performed the before and after chemical analyses, and the commercial organizations treated
the supplied solutions. Of the companies contacted, General Mills Chemical, Inc. (Minneapolis,
Minnesota) agreed to treat some of our high-sulfur refuse drainage solution using chelating
agents; Bio-Rad Laboratories, Inc. (Richmond, California) used ion exchange; Carus Chemical
Co. (LaSalle, Illinois) used permanganate oxidation; and UOP Fluid Systems Div. (San Diego,
California) used reverse osmosis. Diamond Shamrock Chemical Co. (Redwood City, California),
a supplier of ion-exchange resins, expressed an interest in our program and asked to be kept cur-
rent.
Treatment of Contaminated Refuse Drainage by Alkaline Neutralization
Alkaline neutralization is used extensively to treat acid drainage from coal mines. Although it
is well known that alkaline neutralization is very effective in controlling the acid and overall salt
compositions of mine waste waters, the degree of control that this method exerts over some of the
more highly leachable, toxic trace elements remains to be established. Elaboration of this latter
point is the basis for the study that we conducted in this area.
The experiments conducted were basically titrations in which limestone, lime, or lye (NaOH)
were added to one liter of contaminated refuse drainage (iron mostly in ferric state) until a
predetermined pH value was reached. The solutions (or slurries) were allowed to sit overnight
and then filtered, the pH values were measured, and the compositions of the resulting solutions
were analyzed. A brief description of the experiments follows.
• Sample 0 was the control.
• Sample 5 was prepared by titrating with slightly more than the chemical
equivalent of powdered limestone (31.65 g). The limestone was assumed to be
pure CaCOj and buffering effects were neglected.
• Sample 6 was prepared by adding limestone (175 g) to one liter of waste water un-
til there was no further pH change.
• Sample 2 had an elevated pH by adding about 0.2 g of lime to the 35 g of
limestone used initially.
29
-------
• Samples 4 and 1 both were neutralized using lime. The 14.5 g of lime in No. 4
produced a pH of 7.3, and the 17 g of lime in No. 1 produced a pH of 10.7.
• Sample 7 was neutralized with concentrated NaOH to increase pH without hav-
ing the attendant calcium salt precipitation problem.
The results from these alkaline neutralization experiments are seen in Table XVII and show
the effectiveness of this technique for decreasing trace element concentrations in coal waste
leachates. The pH values and iron contents of the treated leachates are within acceptable limits
based on the 1977 EPA effluent limitation guidelines for coal preparation plants (Fe < 3.5 ng/ml>
averaged over 30 days and pH 6-9). Manganese exceeds the acceptable level of 2.5 to 3 jug/m£
averaged over 30 days in the limestone case, however. This is due to the dissolution of manganese
from the limestone during the neutralization of the leachate acid.
As were many techniques discussed in this report, alkaline neutralization was shown to be an
effective method for reducing or abating trace element contamination of coal refuse drainage.
The projected costs for such a treatment are relatively low ($0.10 to $0.80 per ton of cleaned coal,
see Appendix H. Table H-IV). Also the technique is relatively easy to apply, as evidenced by the
large number of neutralization plants already in operation to treat acid mine drainage.
However, in spite of the low cost and ease of application, alkaline neutralization has some
rather considerable disadvantages. For example, it never really treats the source of contamina-
tion (that is, the refuse itself), and hence, its use in treating the drainage from the disposal site
may be needed almost indefinitely. Also, although the standard refuse disposal practice involves
burying the refuse on top of impermeable liners, such as clay, to channel refuse dump drainage
into treatment areas, there is no assurance that drainage will not eventually escape through or
around these liners and thus negate the effectiveness of this method. Another consideration that
may make alkaline neutralization less attractive involves the costs associated with meeting
RCRA requirements. Most certainly, waste materials disposed of in a way that produces con-
taminated drainage will be classified as hazardous. Thus the apparent low cost of alkaline
neutralization may have to be tempered with additional costs needed to meet RCRA permit and
performance requirements. Finally, there is little opportunity for by-product recovery during or
subsequent to neutralization treatment. Thus the potential for realizing economic gain in this
way is quite low.
Although alkaline neutralization as a refuse drainage treatment technique has some rather
severe drawbacks, it is nonetheless widely used, highly accepted, and as this program has shown,
very effective in controlling trace element contaminants. Undoubtedly, this method will continue
to be used widely in the near future to treat contaminated coal refuse effluents.
Treatment of Contaminated Refuse Drainage by Ion Exchange
Bio-Rad Laboratories treated some of our high-sulfur refuse drainage solutions by ion exchange
and returned them to us for analysis. The treatment consisted of flowing 250 ml/mm of leachate
in two equal fractions over 25 cm8 resin beds (1.5 x 15 cm column) at a flow rate of about
'2 ml/min. Four resins were used, making eight samples in all. The first fraction of the leachate
was sufficient to swamp the two resins that were not strongly acidic. A second fraction of the
leachate was too much for all the resins. In the best case, nearly 100 gal. of resin were needed per
1000 gal. of refuse drainage.
Table X VIII provides the catalog description of the resins used and our experiment identifica-
tion numbers. Table XIX is a summary of the results of the ion-exchange experiments. Trace ele-
ment analyses for 14 of the more common trace elements of environmental concern in the Illinois
Basin are tabulated for the original leachate and for the treated solutions. It is clear from the data
in the table that the acidic cation-exchange resins (AG-50W-X8 and AG-MP-50) depressed the
pH of the original solution to even lower values. These, however, were most effective in reducing
the trace element concentrations.
30
-------
TABLE XVII
ANALYSES FOR THE CONTROL OF
REFUSE DRAINAGE BY ALKALINE NEUTRALIZATION"
Sample No.
NEUTRALIZING
AGENT
pH
TDS(%)
Na
Mg
Al
K
Ca
Sc
Ti
V
CT(ng/l)
Mn
Fe
Co
Ni
Cu
Zn
Rb
Ag
Cd(ng/l)
Cs
La
Ce
Sm
Eu
Tb
Dy
Pb^g/4)
Th
U
NONE
(CONTROL)
1.1
0.47
2.4
22
18
2.7
170
<0.4
0.11
15
3.6
820
2.0
3.2
0.53
3.9
18
0.07
13.5
LIMESTONE
7.1
3.14
3.8
66
<0.2
4.3
7700
<0.4
<0.01
1.0
6.4
0.3
0.82
1.00
0.20
0.14
4.6
LIMESTONE LIMESTONE
+ LIME
7.4
3.20
4.8
75
<0.2
8.4
9300
<0.4
<0.01
0.5
4.4
0.3
1.1
1.8
0.19
0.15
0.4
6.6
3.14
3.8
73
<0.2
3.9
8200
<0.4
<0.01
2
3.3
0.4
0.50
0.72
0.22
0.08
<0.2
<0.01
<0.01
<0.01
4
LIME
6.6
3.17
3.8
60
<0.2
3.5
8200
<0.4
<0.01
16
1.0
0.3
0.58
0.69
0.21
0.10
2.4
<0.01
°
1
LIME
10.7
3.07
4.0
30
<0.2
3.3
8000
<0.4
<0.01
62
0.1
0.3
0.23
0.32
0.22
0.04
<0.2
<0.01
°
7
NaOH
5.9
3.36
9400
22
<0.2
4.6
120
<0.01
<0.4
<0.01
1.5
0.07
0.06
0.05
0.05
0.01
0.02
<0.01
<0.01
0.6
<0.04
<0.5
<0.08
<0.02
<0.01
<0.01
<0.02
<0.01
'Values in fig/ml unless otherwise stated.
-------
TABLE XVIII
EXPERIMENT IDENTIFICATION AND CATALOG DESCRIPTION OK RESINS USED IN UIO-KAD'S
ION-EXCHANGE EXPERIMENTS ON HIGH-SULFUR COAL REFUSE LEACHATES
Experiment IDfl Dose
Resin
Mesh Size
Resin Description
831
832
811 1st AG-50VV-X8 -200 to-400
812 2nd AG-50W-X8
1st AC-MP-50
2nd AG-MI'-frt)
841 1st AG-50I-X8
842 2nd AG-50I-X8
•Leachate CTWT-8 was used.
-200 to-400
1st Chele.x 100 -100 to-200
2nd Chelex 100
-20 to-50
A strongly acidic cation exchange
resin composed of nuclear sulf'onic
acid exchange groups attached to a
styrene divinylbenzene polymer
lattice.
A strongly acidic, macroporous cat-
ion-exchange resin with nuclear
sulf'onic acid exchange groups. The
resin has an effective surface area
approximating 35 mVdry g or 30-
35% porosity.
A chelating resin that is a
styrene divinylbenzene copolymer
containing iminodiacetate functional
groups, structurally classed
with the weak acid cation exchangers
by virtue of its carboxylic acid
groups.
A mixed bed resin for deinnization
with equivalent amounts of AG-50VV-X8
H+ formand AG-1-X8OH- form.
-------
TABLE XIX
SUMMARY OF pH, TDS. AND TRACE ELEMENT COMPOSITIONS
RESULTING FROM ION-EXCHANGE TREATMENT OF A HIGH-SULFUR
COAL REFUSE LEACHATE"
pH
TDS(%)
Al
Ca
Co
Cu
F
Fe
K
Mn
Na
Ni
Ti
Zn
•All r
INITIAL
LEACHATE
AG-50W-x8
811
812
AG-MP-50
821 822
Chelex 100
AG-501-xS
831
832
841
iMcoiitrnliiins in
except where
842
1.8
3.26
540
170
400
7
160
0.15
600
28
15
8
17
27
0.85
2.62
<0.5
0.9
0.4
<0.05
no
<0.02
2.8
0.2
2.3
<0.02
2.6
0.08
<0.5
0.06
1.45
3.12
26
7.8
140
8
135
0.15
4.4
7550
23
13
17
13
<0.5
28
0.88
2.52
4
0.6
0.4
0.4
270
<0.02
3.3
36
12(
.2
)
.2
2.00
3.37
430
4.2
90
10
220
0.15
5.1
8190
3.3
15
48
15
1.2
31
2.68
3.15
110
290
70
0.3
220
<0.02
2.5
4820
30
0.3
33000
0.3
<0.5
0.3
2.54
3.99
820
360
650
16
410
0.06
6.3
7550
12
21
1170
21
<0.5
65
1.94
1.74
180
115
110
5
180
0.1
3.3
3910
17
8
11
8
<0.5
14
2.37
3.33
440
330
120
9
300
0.16
5.2
7370
0.04
14
9
14
<0.5
28
These experiments are preliminary in nature and were designed to demonstrate the ap-
plicability of this particular water cleaning technology to the problem of undesirable trace ele-
ment contamination of high-sulfur coal preparation waste leachates. Therefore, we did not at-
tempt to complete an economic analysis of this control option. Using data from the literature, we
estimate that the cost of treating acid refuse drainage with ion exchange would be in the area of
$0.29 per ton of cleaned coal (Appendix B, Table B-IV). It is recognized that should we pursue the
ion-exchange method for acid mine drainage and refuse leachate clean-up, we should also need to
consider (a) the effect of solution pH control on trace element removal, (b) resin type, (c) resin
capacities, (d) resin regeneration, and (e) related items, such as capital and operational costs. It
is clear, however, that ion exchange can reduce concentrations of trace elements of environmental
concern in refuse leachates to acceptable levels (note Expt No. 811 in Table XLX), though the
need to further treat these solutions for acid greatly reduces the applicability of the method. This
and the known tendency of ion-exchange to overload or plug when the contaminant or suspended
solids contents are high lead us to believe that ion exchange might be most applicable as a secon-
dary treatment method to clean up the effluents from some other control process.
Treatment of Contaminated Refuse Drainage by Reverse Osmosis
Reverse osmosis (RO) is a technique that is used widely to desalinate seawater and other types
of contaminated drainages produced by agricultural and industrial operations. In this method, a
series of semipermeable membranes or filters are used to segregate or isolate dissolved contami-
nants from the main volume of water. Separation is achieved by forcing water that is relatively
33
-------
free of contaminants through the filter while retaining the contaminants in a concentrated liquor
on the upstream side of the filter. This produces clean or product water and contaminated or re-
ject water. There are many variables that can affect the performance of an RO water treatment
system, including the composition of the contaminated water, the efficiency and selectivity of the
filter material, and the number of times the water is passed through the filter bank.
A series of preliminary, bench-scale experiments to test the effectiveness of RO at cleaning con-
taminated refuse water were performed for us by UOP Fluid Systems Division. In these experi-
ments, UOP used two types of RO filters designated as Filters 1 and 2 in Table XX. Filter 1 was
UOP's RC-100, which is a poly(ether/urea) membrane, and Filter 2 was UOP's PA-300, which is a
poly(ether/amide) membrane. The initial feed solution (Sample 01) of contaminated refuse
drainage was passed through each of these RO filters. The compositions of the respective product
or treated waters from the first pass through each of the filter units are listed under Samples 02
and 03 in Table XX. These data show that both filters were quite effective at reducing the
priority trace elements in the refuse leachates to acceptable levels. Filter 1 appeared to be the
better of the two for this purpose, but a suspected break in Filter 2 probably negated its an-
ticipated better performance. (Note that as was the case for the ion-exchange studies that we
conducted, reverse osmosis did not appreciably affect the pH of the refuse leachates.) The
analyses for the combined reject waters from the first passes through both membranes also are
listed in Table XX (Sample 04).
In the next stage of the RO experiment, the reject water (now the feed solution) was split and
passed through each filter type. This process was continued until the reject water had been suc-
cessively passed through each filter five more times. The analyses for the now highly con-
centrated feed solution just before the seventh pass through the filters (Sample 19) and the
analyses of the cleaned or product water derived by RO from this concentrated feed (Samples 20
and 21) are in the last three columns of Table XX. These latter data, of course, reveal the perhaps
marginal effectiveness of the RO method at treating highly concentrated waste leachates. Here
Filter 1 (the RC-100 membrane) still reduced I he concentrations oft rare coniaiiiinanis to accept -
able levels, whereas the iron and manganese levels ol the product water from treatment with
Filter 2 exceeded presently established point source levels. The reduction of iron content during
the first and seventh passes through each membrane is depicted graphically in Fig. 3.
An important consideration in the use of RO concerns the ratio of the final reject water that
will still need further treatment before final disposal and the total amount of water treated. Peak
recovery when placing six filters in series is 80-85%. Thus 15-20% of the original volume of
drainage will still need to be treated. The magnitude of water is less, but all of the contamination
is still present and still needs to be treated.
The work that we have conducted thus far shows that RO, like ion exchange, can be quite effec-
tive under some circumstances for treating trace element contamination in coal refuse drainage.
RO is marginally effective for highly concentrated leachates (Table XX) and is apparently quite
susceptible to membrane fouling by suspended particulates and solids. In addition, it is neces-
sary to further treat the effluents from RO to reduce the acidity to acceptable levels. These con-
siderations suggest that RO, like ion exchange, may function best as a secondary method to
polish off effluents from the alkaline neutralization of acid refuse drainages. Data in the
literature suggest that the cost of using RO to treat coal refuse drainage would be in the range of
$0.20 per ton of cleaned coal (Appendix B, Table B-IV).
Permanganate Oxidation to Treat Coal Refuse Drainage
One of the problems with direct alkaline neutralization of coal refuse drainage to control trace
contaminants is that some elements (notably, iron and manganese) are not precipitated from
34
-------
TABLE XX
TRACE ELEMENT ANALYSES ON REVERSE OSMOSIS EXPERIMENTS
Sample No.0 01 02 03 04 19 20 21
Pass thru system
Process Position
Filter Type"
Cond (^imhos)
pH
TDS (%)
Al
Ca
Cd (ng/t)
Co
Cr
Cu
F
Fe
Mn
Ni
Zn
1st
Feed
-
5 090
2.38
0.55
174
230
102
0.8
0.19
2.0
4.1
235
73.7
2.1
7.4
1"
Product
1
1 780
2.39
<0.01
<0.1
7.4
<1
<0.01
<0.001
<0.01
0.1
0.08
<0.01
<0.01
0.01
I8t
Product
2
1 140
2.61
<0.01
0.7
4.6
<1.0
<0.01
<0.001
0.01
0.1
1.64
0.32
<0.01
0.04
I8t
Reject
1+2
-
2.36
0.73
206
280
110
0.9
0.26
2.5
4.6
298
86.6
2.6
8.8
Tth
Feed
-
21 600
2.02
4.54
1 390
1 480
680
6.4
1.8
20.7
9.9
2 020
620
23.3
58.3
nth
Product
1
4 710
1.93
0.02
<0.1
3.3
<1
<0.01
0.005
<0.01
0.1
0.22
0.02
<0.01
0.02
•7th
Product
2
3 280
2.15
0.05
8.9
7.9
5
0.05
0.03
0.16
0.3
17.8
4.4
0.16
0.46
•Concentrations reported as pg/ml unless noted otherwise.
"See text.
-------
10000
tooo -
o.oi -
FEED
FILTER-1 FILTER-2 REJECT
Fig. 3.
Iron levels in aqueous streams of a reverse osmosis system.
solution in their lower oxidation states by merely adjusting the pH to the neutral point. To cir-
cumvent this problem, acid drainage treatment facilities usually precede the neutralization step
by some type of oxidation reaction to convert such components as Fe+l and Mn+l to higher oxida-
tion states that precipitate from solution in the range of pH 5 to 6.
During the year, Carus Chemical Company conducted several experiments for us in which per-
manganate was used as an oxidizing agent to maximize the valences of the components in a con-
taminated coal refuse leachate. The intent here, of course, was to increase the effectiveness of the
alkaline neutralization of the resulting solution. The leachate used had a very high concentration
of iron, over 50% of which was in the Fe+a state. The product water produced by the combined ox-
idation/neutralization process shows clearly that this method can be quite effective at reducing
the trace elements in a contaminated refuse drainage sample to acceptable levels. (See Table
XXI.)
Because of the success with neutralization alone, we do not have further experiments planned
in this area.
Chelating Agents to Control Trace Elements in Coal Refuse Drainage
General Mills Chemical, Inc. participated with us in an investigation of the use of chelating
agents to remove heavy metal contaminants from coal refuse drainages. Our collaborators at
36
-------
pH
TDS (%)
Al
Ca
Cd
Cr
Co
Cu
Fe
Mn
Ni
Zn
Na
K
1.8
3.25
540
170
0.4
0.16
7
0.15
6600
15
17
27
8
28
TABLE XXI
ALKALINE NEUTRALIZATION/PERMANGANATE OXIDATION OF
CONTAMINATED COAL REFUSE DRAINAGE
Starting Cams
Parameter8 Solution Sample No. 2b
6.92
0.45
<0.1
520
<0.001
0.002
<0.01
<0.01
0.055
0.36
<0.01
0.01
11.8
860
•Cnnrenl rat inns reported as mf.ll.
"pll adjusted to 7 with Ca(OH),.
General Mills treated a contaminated refuse leachate that we sent them with several commercial
and experimental chelating agents. We have not yet received the results of these experiments
from them. However, they have reported that because of the highly acidic leachates (pH ~ 2),
none of the agents tested were effective in reducing the metals content.
No further experiments are planned in this area.
Subtask 1.3—Define Options for Controlling Trace Element Releases in the Drainages
From Coal Refuse
The purpose of this activity is to assess the results and major implications stemming from the
research that we have conducted thus far on environmental control technologies for trace element
contamination of coal refuse drainages. Also in this subtask we will delineate those areas where
more work needs to be done, either to complete our understanding of the various environmental
options or to solve specific control problems. The foregoing discussions have emphasized the
technical feasibility and some advantages, disadvantages, and tradeoffs that need to be con-
sidered when choosing among environmental control methods for preventing or treating con-
taminated coal refuse drainage. The major issues in this regard for many of the control methods
considered in this report appear in Tables XXII and XXIII. For the most part, the comparison
grid in the executive summary condenses the information discussed in the previous sections. Ar-
ranging the information in a grid illustrates the complexity involved in choosing from among the
various control possibilities.
37
-------
TABLE XXII
MATKIX GRID SUMMARY OF ENVIRONMENTAL CONTROL
OPTIONS FOR CONTAMINATED COAL REFUSE DRAINAGE
Parameter
Cost"
Effectiveness*1
Likely RCRA
Classification
Lime Fly Ash Soil
Calcining Preleaching Codisposal Codisposal Codisposal
high
excellent
Process complexity high
Treatment duration" short
By-product potential high
Permanency excellent
very high"
good
high
short
high
good'
moderate mod. to high moderate0
good good good
low low low
short
none
short
none
short
none
nonhazard
"Kauri's IVoin ii hifjh of >-S"> (197S)/lon of cleaned coal lo a low of $0.'J()/lon of cleaned coal.
"('MM be jiisiil'ied only by development olby-product recovery technology.
cSiie specific.
"Ability lo preveiil or abate conlaininaled drainage.
''Shori means days to months.
'Must be confirmed by further experiments.
The relative costs of the control methods under consideration vary from quite high (perhaps as
much as $5.00 per ton of cleaned coal for refuse calcining) to fairly low ($0.20 per ton of cleaned
coal for alkaline treatment of refuse drainage). In general, the costs tend to reflect the complexity
of the control processes. It is noteworthy that the most costly types of controls are also potentially
the most permanent and environmentally desirable solutions to the refuse disposal problem. As
indicated in the tables, several of the refuse drainage control methods that we are studying have
some potential for by-product recovery. This factor could significantly reduce the overall pollu-
tion control cost.
Our research suggests that each of the control techniques listed in Tables XXII and XXin is
quite effective over short periods of time. One of the major areas that remains to be defined for
many of the methods under consideration is the long-term effectiveness or permanency of the
proposed solutions. Answers to this question are being sought from scale-up experiments that
more closely simulate actual waste dump conditions than the small scale laboratory experiments
that we have been working with.
The last item of importance on the tables concerns the possible constraints imposed by RCRA
on the handling and disposal of coal refuse materials. Wastes classified as hazardous by RCRA
will involve a maze of paperwork and conformance to regulations that will be quite expensive to
negotiate. This consideration alone may represent the singlemost important cost in refuse dis-
posal. The RCRA posture with regard to large volume wastes is still being defined; consequently
38
-------
TABLE XXIII
MATRIX GRID SUMMARY OF ENVIRONMENTAL CONTROL
OPTIONS FOR CONTAMINATED COAL REFUSE DRAINAGE
Parameter
Alkaline Reverse Ion
Neutralization Osmosis Exchange
Cost8
low
Effectiveness" good
Process complexity moderate
Treatment duration0 very long
By-product potential none
Permanency poor
Likely RCRA
Classification
hazardous
moderate
some"
poor
moderate
good
high
very long
good
high
very long
some"
poor
hazardous hazardous
"Himjjes from n high of >$5 (1978)/ton of cleaned coal In a low of $0.20/1 on of dimmed coal.
"Ability to prevent or abate contaminated drainage.
c\'i'rv lon» means indefinitely.
"Ky-product is potable water.
we cannot yet identify the probable RCRA classification for many of the waste treatment
schemes that we are studying.
The nature of the tradeoffs to be made among the various control options for disposal of acidic
coal refuse materials is beginning to emerge. The methods that potentially provide the most ef-
fective and permanent means of abating trace element contamination of refuse drainage (calcin-
ing and preleaching) are also the most costly and complex methods to use. The control techni-
ques that are designed to retain contaminants within the refuse disposal site, such as codisposal
with various agents, are effective for attenuating the trace element compositions of refuse
drainages for at least short durations, but some of these may lack long-term effectiveness. Accept -
ability for nonha/.ardous RCRA disposal requirements is another questionable aspect. Finally,
the methods to treat refuse drainage (alkaline neutralization and reverse osmosis) appear to be
quite attractive because of their relatively low costs and effective trace element reduction, but
these are methods fraught with other potential problems. These include indefinite treatment
duration, possible contaminant escape, and cost to meet RCRA permit and performance require-
ments for hazardous wastes.
Future work in this program will provide further elucidation of the technical feasibilities and
cost/benefit tradeoffs of these and other environmental control options for contaminated coal
refuse drainage.
39
-------
TASK 2-IDENTIFY TRACE ELEMENTS OF ENVIRONMENTAL CONCERN IN HIGH-
SULFUR COAL PREPARATION WASTES FROM THE APPALACHIAN REGION
Sub task 2.1—Assess Trace Element Structure and Mineralogy in Representative Refuse
Samples
The emphasis of this subtask is to determine sufficient detail about the structure and
mineralogy of selected samples of Appalachian Region refuse (and coal) to establish an under-
standing of the trace elements of greatest environmental concern and to aid in the selection of ap-
propriate environmental control for trace element contamination of refuse dump effluents.
Chronologically, there are several parts to this activity: sample selection and collection; trace ele-
ment and mineralogical characterization of the bulk refuse samples; and detailed delineation of
the mineralogy of specific trace elements of interest.
Sample Collection From Homer City Coal Cleaning Plant
We are pursuing our originally stated intent, that of trying to obtain some samples from the
new multistream coal preparation plant at Homer City, Pennsylvania. We have received formal
approval from the Pennsylvania Electric Company (PENNELEC) for a visit to their facility to
collect these samples. As soon as all the necessary details can be attended to, we will proceed.
Meanwhile, we have been characterizing the structure and behavior of a low-sulfur coal cleaning
plant refuse from the Appalachian Region (Plant G).
Structural Studies of Appalachian Region Coal Refuse
We have completed our assessment of the bulk mineralogy and trace element compositions of
several refuse fractions from Appalachian Plant G refuse. Average mineral compositions from x-
ray diffraction analyses of three refuse fractions, two coarse and one fine, from this plant are com-
pared with average values from similar analyses of Illinois Basin Plant B refuse in Table XXIV.
TABLE XXIV
MINERAL COMPOSITIONS OF COAL REFUSE SAMPLES
Plant Ga Plant B"
Mineral Average Wt % Average Wt %
Kaolinite 11 7
Illite 19 11
Quartz 22 17
Pyrite/Marcasite <1 26
Calcite 1 0
Mixed Clay 6 17
Gypsum 1 1
"I,mv.sulfur ri'l'use.
"Mijili-siiH'iir ri'fuse.
40
-------
The mineralogy of the Plant G refuse is notably different from that of the Illinois Basin refuse
materials that we have been studying. There is very little detectable pyrite or marcasite in the
Plant G refuse (<1 wt%), and the clay minerals and quartz represent over 60 wt% of the refuse
composition. Small amounts of calcite and gypsum compose the remainder of the detectable
mineral matter in the refuse. Therefore, the acid-generating potential of the Plant G material
should be very low. An unusually large fraction of the total mineral composition of the Plant G
refuse (20 to 25 wt%) was either microcrystalline or amorphous and could not be analyzed by x-
ray diffraction methods.
The trace element analyses for the Plant G refuse samples are now complete, and those data
are tabulated in Table XXV. Using a portion of the available analytic data, we have compared
the trace element make-up of the Plant G refuse with that from a high-sulfur (Plant B) Illinois
Basin coal refuse. This is done in Table XXVI. Here it is seen that the most notable difference is
in the iron content, with Plant G having 2% and Plant B having 11%. This, of course, is a reflec-
tion of the low, iron sulfide mineral content in this sample of Appalachian coal waste. Except for
copper, the trace elements are also lower for the Eastern coal. The relatively higher aluminum
and silicon values in the Plant G refuse reflect the higher clay and quartz concentrations. From
an environmental viewpoint, the Plant G refuse contains potentially troublesome quantities (>50
Mg/g of refuse) of aluminum iron, manganese, nickel, and zinc.
The trace element/mineral associations of the Plant G refuse will be reported next year.
Subtask 2.2—Determine Environmental Behavior of the Trace Elements in Refuse Samples
The activities in this subtask are an extension of the environmental weathering and leaching
studies, which we conducted previously on Illinois Basin refuse.to selected samples of refuse from
the Appalachian Region. The purpose of the research in this subtask is (1) to develop an under-
standing of the environmental behavior of the trace elements in selected Appalachian Region
refuse (and coals) under typical waste dump or storage conditions and (2) to identify the trace
elements of greatest environmental concern in these materials. This work, as well as our previous
work on the leachability of Illinois Basin refuse, is directed toward defining the technology needs
for controlling or preventing trace element contamination of the aqueous drainage from the thou-
sands of refuse dumps, culm banks, and coal storage piles located in the Eastern and Midwestern
United States.
Environmental Assessment of a Low-Sulfur Refuse From the Appalachian Region
Static and dynamic leaching tests have been conducted on the Plant G refuse material. These
studies were designed to simulate the weathering and leaching behavior of the refuse materials
and to yield data on those potentially troublesome trace elements that may be released into the
environment. We have identified aluminum, iron, manganese, nickel, and zinc as residing in the
Plant G refuse in quantities >50 ^g/g of refuse and therefore likely to be released in concentra-
tions high enough to be of environmental concern.
Static leaching tests were performed on 50-g portions (-20 mesh) of Plant G refuse derived from
the two coarse fractions. These portions were leached with 200 m£ of water in a system open to air
and at room temperature for periods of up to 42 days. The detailed pH and trace element
analyses of these samples appear in Table XXVII. Note that the pH remained fairly constant
around 4 for the first 2 wk but at 42 days it had decreased to 3. This decrease probably occurred
by a gradual depletion of the small amount of neutralizing capacity naturally present in the
refuse material in the form of calcite.
41
-------
TABLE XXV
TRACE ELEMENT AND MINERAL CONTENT OK COAL
WASTE FROM APPALACHIAN PLANT C
SAMPLE
140
141
(1)
IDENTITY
LOCALE
DATE OBTND
PCT H20
PCT LTA
PCT ORIGNL
SIZE, KG
CHNS ANAL
NITROGEN
SULFUR
MINERALOGY
KAOLINITE
ILLITE
QUARTZ
PYRITE
CALCITE
MIXED CLAY
GYPSUM
SAMPLE
ELEMENT
(2)
LI PPM H A
EE PPM H A
B PPM L E
F PPM R 0
NA PCT H A
KG PCT H A
AL PCT H A
SI PCT R 0
P PPM R 0
CL PPM R N
K PCT H A
CA PCT H A
SC PPM R N
TI PCT R N
V PPM R N
CR PPM H A
MN PPM H A
FE PCT H A
CO PPM R N
HI PPM L E
CU PPM II A
ZN PPM H A
GA PPM R N
GE PPM L E
AS PPM H N
RB PPM H N
Y PPM L E
ZR PPM L E
MO PPM L E
CD PPM H A
SN PPM L E
SB PPM R N
CS PPM R N
LA PPM R N
CE PPM R N
SM PPM R N
EU PPM R N
TB PPM R N
DY PPM R N
YB PPM R N
LU PPM R N
HF PPM R N
U PPM R N
W PPM R N
PB PPM H A
TH PPM R 0
U PPM R 0
GOB A CORS
PLANT G
06/23/76
4.54
84.82
100.00
59.70
.28
.60
11.18
19.03
23.87
-1.00
1.03
7.47
1.52
40
RAW BASIS
119.00
3.00
56.00
600.00
.17
.52
9.56
20.20
160.00
2.07
.12
15.80
.73
87^00
93.90
jioo
55.00
43.00
72.00
22.20
-8.00
14.20
121.00
21.00
160.00
-8.00.
.20
-8.00
2-22
58.30
74.50
6.09
1.13
.80
5.82
2.83
.59
V.K
22.00
15.60
5.32
42
FN GOb
PLANT G
06/23/76
20.14
73.35
100.00
42.60
.16
.66
11.16
19.46
21.31
-1.00
1.92
6.29
.76
12
RAW'BASIS"
1 14.00
1.80
52.00
550.00
.12
.
20.10
150.00
GOB B CORS
PLANT G
06/23/76
U.60
81.52
100.00
60.80
.12
.61
11.31
19.61
19.76
-1.00
.19
3.1§
1.58
41
RAW'BASIS*
132.00
2.60
S6.00
560.00
. 11
.57
9.25
20.45
150.00
2.05
!67
116.00
104.00
96.75
2.05
11.00
46.00
53.00
69.00
-8! 60
20.30
131.00
19.00
130.00
-8.00
.40
-8.00
2.95
9.58
52.40
85.80
5.50
1.50
1.56
5.68
2.46
.56
4.82
1.14
20:00
15.80
4.40
•I'l.l'S OH MINI'S INDICATES VALUE GREATER OR LESS THAN THAT lilVKX. NTMHKHS li oil I.AHCKK
AKK MKSH SIZES. OTHERS ARE IN INCHES.
•I.K1TKKS INDICATE HOW SAMPLE WAS PREPARED AND ANAI.W.KD
It-liAW SAMI'LK
I.= I.OU TKMPKHATl'HE ASH
H-HICII TEMPERATURE ASH
N-NKl I'KON ACTIVATION ANALYSES
A-ATOMIC ABSOKITION
K- EMISSION SPKCTHOSCOPV
0-OTHEK
.
17.00
-6.00
42
-------
TABLE XXVI
TRACE ELEMENT COMPOSITIONS OF
COAL REFUSE SAMPLES
Average Average
Element8 Plant Gb Plant Bc
5.1
13.6
144
11
30
71
35.4
149
94
Al (%)
Si (%)
Mn
Fe (%)
Co
Ni
Cu
Zn
As
9.2
20.2
97 '
2.0
12
49
48
69
17.7
•Compositions reported as
"l/iw-sulfur refuse.
"Hijih-sullur refuse.
unless otherwise noted.
TABLE XXVII
STATIC LEACHING OF LOW-SULFUR
APPALACHIAN PLANT G WASTE
Sample No."
Time (Days) 0.01 1
16
42
pH
TDS (%)
F
Na
Mg
Al
K
Ca
C.r( j/K/mtf)
Mn
Fe
Co
Ni
Cu
Zn
CdUK/mg)
3.9
0.10
1.4
18
240
29
90
580
49
6
15
1.5
3
3
4
30
4.3
0.13
2.0
20
250
25
130
810
7
7
16
1.5
4
1
5
31
4.3
0.09
2.3
29
270
28
135
850
9
8
16
2
4
1
6
27
4.1
0.10
2.6
25
260
40
170
840
7
8
11
2
5
2
7
46
3.0"
0.23"
3.1
29
320
280
165
960
300
12
31
3
6
6
15
25
•Viiliii's in
"Sw lext.
. nf wnsle unless noted otherwise.
43
-------
Column leaching studies were also done on Plant G refuse, in which 500 g of material (-3/8 in.)
was packed into glass columns 5 cm in diameter by 40 cm long. Distilled water at a flow rate of 0.5
ml/mm was passed upward through the columns. For two samples (GL-23 and GL-24), the flow
of water was stopped after approximately 3 liters had passed through, and the columns were al-
lowed to dry out. Intermittently, these aired columns were moistened during a 2-wk period to
simulate the wet and dry periods encountered by a refuse pile. At the end of the 2-wk period,
water flow was resumed as before until a total leach volume of 10 i had passed through the
column. The behavior of the material as reflected by the pH and the TDS values as a function of
water volume passed through the column is shown in Fig. 4. At no time did the pH reach the low
levels of the high-sulfur Illinois Basin refuse, but there was much more acid-generating capability
in the Plant G refuse than might have been anticipated from the low pyrite/marcasite content of
the material. It is possible that pyrite in an amorphous, subcrystalline form not detectable by x-
ray diffraction analysis is an active generator of acid. Perhaps a clearer understanding of the
acid-generating capacity of this refuse will come about as we continue our studies of trace
element/mineral associations.
In an effort to assess which elements present in the Appalachian Plant G refuse are of en-
vironmental concern, an analysis of the data from the leaching experiments was made according
to the procedure described in Ref. 5. Using the (MATE) criteria established by the EPA and in-
cluding a dilution factor (lOOX)indicative of the natural dilution of process effluents by surface or
ground waters, we determined an adjusted MATE value. That value for each element was
divided into the leachate concentration of that element to ascertain the relative environmental
hazard of that refuse constituent. For this purpose elemental concentrations were chosen when
100 m£of water had passed through 500 g of waste. When a hazard factor is near or greater than 1,
the potential of an element to cause an environmental problem is signaled. Table XXVIII in-
dicates that the elements aluminum, copper, iron, manganese, nickel, and zinc are of en-
vironmental concern in the Plant G coal refuse.
Further evaluation of the environmental behavior of Plant G refuse will be included in future
reports on this project.
PERSONNEL
A large number of LASL personnel besides the authors participated in the programmatic effort
during the year. Their work and contributions are gratefully acknowledged.
Administrative Advisors: R. D. Baker, R. J. Bard, and R. C. Feber
Analytic Advisors: G. R. Waterbury and M. E. Bunker
Neutron-Activation Analyses: W. K. Hensley and M. E. Hunker
Atomic Absorption Spectrophotometry and Wet Chemisty: E. J. Cokal, L. E. Thorn,
and W. H. Ashley
Spectrochemical Analysis: 0. R. Simi, J. V. Pena, and D. W. Steinhaus
Electron and Ion Microprobe: W. F.Zelezny, N. E. Elliot, W. B. Hulrhinson,
W. 0. Wallace, R. Raymond, and R. C. Gooley
X-Ray Diffraction Analyses: R. B. Roof
Optical and SEM Microscopy: R. D. Reiswig and L. S. Levinson
Statistical Evaluation: R. J. Beckman
-------
a
if)
(N
s
r^
cp
ii
>5 30
4-5 60 75
VOLIM! (Liters)
LEGEND
o = GL-23
o = a-24
* = GL-25
o = a-26
(a)
(b)
120
Fig. 4.
Leachate pH and TDS versus volume for column leaching study of Plant G refuse.
45
-------
TABLE XXVIII
MEG/MATE ANALYSES OF PLANT G
COAL REFUSE LEACHATE
ELEMENT
Ni
Fe
Mn
Cu
Al
Zn
Cd
Ca
Co
Mg
K
Cr
F
Na
LEACHATE8
LEVEL, PPM
3.8
50
10
4.8
90
7.2
0.033
320
1.9
250
26
0.12
1.4
16
PLANT G
ADJUSTED MATE"
VALUE, PPM
1
25
10
5
100
10
0.1
1 600
25
8 700
2 300
25
380
80 000
HAZARD
FACTOR0
4
2
1
1
0.9
0.7
0.3
0.2
0.07
0.02
0.01
0.004
0.003
0.0002
"Column leach; 100-ml aliquot; 500 g of refuse.
"lOOx MATE value for liquids.
cLeachate value/adjusted MATE value.
APPENDIX A
COLUMN LEACHING STUDIES OF CALCINED REFUSE
TABLE A-I
EXPERIMENT IDENTIFICATION FOR DYNAMIC LEACHING
STUDIES OF CALCINED REFUSE
Sample Size
Experiment No. Sample" (kg)
GL-12 Control 1.5
GL-18 Calcined refuse 1.5
•Minus 3/8 in. Plant B refuse used.
46
-------
TABLE A-H
ANALYSES FOR DYNAMIC LEACHING
STUDIES OF CALCINED REFUSE
Experiment No. GL-12
Sample No.
Parameter*
Vol (/)
pH
TDS(%)
Na
Mg
Al
K
Ca
Sc
Ti
V
CrOig/i)
Mn
Fe
Co
Ni
Cu
Zn
Ga
As
Br
Rb
Mo
Ag
CdOig//)
Cs
La
Ce
Sm
Eu
Tb
Dy
Yb
Lu
Hf
Ta
\V
Pb(ng/i)
Th
U
1
0.040
1.3
8.63
25
500
1600
51
530
3.0
<0.4
1.44
790
130
15000
36
51
10
76
<0.2
7.9
<0.04
<2
<5
<0.01
430
<0.04
1.3
5.3
0.83
0.35
0.47
0.14
0.25
0.05
<0.02
<0.05
0.04
1100
1.7
0.46
3
0.580
1.6
3.13
8
170
520
11
440
0.78
<0.4
0.71
420
19
5300
13
19
1.5
38
<0.2
1.3
<2
<4
<0.01
130
<0.04
0.60
1.4
0.34
0.11
0.02
0.08
0.11
0.02
<0.02
<0.05
<0.04
210
0.34
0.31
4
1.290
2.1
1.02
4
43
130
13
260
0.14
<0.4
0.42
85
8
1700
4
8
<0.9
13
<0.2
0.58
<0.04
<2
<9
<0.01
85
<0.04
0.26
0.53
0.12
0.03
<0.1
0.03
<0.03
<0.01
<0.02
<0.05
<0.04
60
0.04
0.19
7
2.365
2.2
0.55
3
29
61
6
210
0.03
<0.4
0.21
38
3
930
3
3
<0.06
6
<0.2
0.65
<0.04
<2
<1
<0.01
35
<0.04
<0.5
0.44
0.06
0.02
<0.1
0.43
<0.03
<0.01
<0.02
<0.05
<0.04
45
<0.02
0.01
8
3.345
2.5
0.08
1
7
7
4
52
<0.01
0.16
0.04
<4
0.7
200
0.4
0.7
<0.07
1
<0.2
0.08
<0.04
<2
<1
<0.01
4
<0.04
<0.5
0.09
<0.02
<0.01
<0.1
0.04
<0.03
<0.01
<0.02
<0.05
<0.04
12
<0.02
<0.01
10
4. 175*
2.6
0.11
1
28
4
3
47
<0.01
<0.4
0.04
<5
0.5
170
0.2
0.5
<0.09 -
1
<.2
0.07
<0.04
<2
<1
<0.01
19
<0.04
<0.5
<0.08
<0.02
<0.01
<0.1
0.02
<0.03
<0.01
<0.02
<0.05
<0.04
51
<0.02
<0.01
18
7.735
1.7
3.87
3
56
450
4
230
0.77
<0.4
0.38
260
7
7600
4
7
4
11
<0.2
2.8
<0.04
<2
<1
<0.01
41
<0.04
0.2
1.1
0.19
0.08
<0.1
0.12
<0.03
0.02
<0.02
<0.05
<0.04
110
0.43
0.14
20
8.290
1.8
1.87
1
30
230
5
140
0.31
<0.4
0.16
160
4
3300
2
5
1
6
<0.2
0.56
<0.04
<2
<1
<0.01
30
<0.04
0'2
1.0
0.14
0.04
<0.1
0.03
<0.03
0.01
<0.02
<0.05
<0.04
30
0.15
0.06
23
9.855
2.2
0.33
0.9
4
22
4
35
0.01
<0.4
0.07
13
0.9
650
0.4
0.9
<0.09
1
<0.2
0.1
<0.04
<2
<1
<0.01
22
<0.04
<0.5
0.2
<0.02
<0.01
<0.1
0.01
<0.03
-------
TABLE A-II1
ANALYSES FOR DYNAMIC LEACHING
STUDIES OF CALCINED REFUSE
Experiment No. GL-18
Level in Sample No.
Parameter*
Volt/)
pH
TDS(%)
Na
Mg
Al
SiO,
P
K
Ca
Sc
Ti
V
CrUg/J)
Mn
Fe
Co
Ni
Cu
Zn
Ga
As
Br
Rb
Mo
Ag
Cd^g/J)
Cs
La
Ce
Sm
Eu
Tb
Dy
Yb
Lu
Hf
Ta
\V
PbOig//)
Th
U
Material0
(ppm)
1140.
4900.
115000.
168000.
560.
24500.
3200.
29.3
5490.
118.
100000.
191.
190000.
69.9
73.
296.
28.6
108.
<0.1
371.
<0.1
290.
15.8
98.6
229.
29.6
3.21
8.68
1.11
8.48
1.66
8.15
12000.
25.4
9.55
1
0.060
3.9
1.91
350.
940.
170.
2300.
590.
0.08
<0.4
0.17
55.
75.
680.
7.
7.
<0.08
10.
<0.2
0.13
0.1
3.57
<1.
<0.01
7.
0.09
1.92
2.35
0.66
0.19
<0.1
0.40
0.13
0.02
<0.02
<0.05
<0.04
10.
<0.02
0.64
2
0.155
3.8
1.48
260.
710.
85.
1600.
610.
0.03
<0.4
0.09
14.
61.
610.
5.
5.
<0.08
4.
<0.2
0.08
<0.04
2.11
<1.
<0.01
0.5
0.04
0.87
1.57
0.30
0.14
<0.1
0.31
0.06
0.02
<0.02
<0.05
<0.04
14.
<0.02
0.27
3
0.765
4.1
0.57
67.
1780.
3.
710.
690.
<0.01
<0.4
<0.0l
2.
16.
180.
0.5
0.6
<0.02
0.2
<0.2
<0.02
<0.04
<2.
<0.2
<0.01
0.9
<0.04
0.14
0.39
<0.02
0.02
<0.1
0.05
<0.03
<0.0l
<0.02
<0.05
<0.04
<5.
<0.02
0.01
6
2.795
5.7
0.03
2.
4.
<0.1
13.
45.
<0.01
<0.4
<0.01
<1.
0.3
3.
<0.02
<0.05
<0.02
<0.01
<0.2
<0.02
<0.04
<2.
<0.2
<0.01
0.04
<0.04
<0.5
<0.08
<0.02
<0.01
<0.1
<0.01
<0.03
<0.01
<0.02
<0.05
<0.04
<5.
<0.02
<0.01
19
13.740
4.9
0.06
7.
8.
<0.8
33.
58.
<0.01
<0.4
<0.01
<8.
2.
25.
0.8
1.7
<0.17
3.
<0.2
<0.02
<0.04
<2.
<1.
<0.01
3.
<0.04
<0.5
0.85
<0.02
<0.01
<0.1
<0.01
<0.03
<0.01
<0.02
<0.05
<0.04
<42.
<0.02
0.01
26
18.630
5.7
0.01
1.
0.5
<0.1
2.
3.
<0.01
<0.4
<0.01
<3.
0.1
2.
<0.05
<0.1
<0.05
0.1
<0.2
0.03
<0.04
<2.
<1.
<0.01
<0.05
<0.04
<0.5
<0.08
<0.02
<0.01
<0.1
<0.01
<0.03
<0.01
<0.02
<0.05
<0.04
<13.
<0.02
<0.01
"Values in n$Jmt unless otherwise stated.
"\Vaier How was stopped at 4.01. air was passed through the column Tor 4 wit. then water flow was resumed.
48
-------
1.°.
LEGEND
= CL - IB
= GL-12
2.50 3.75 5.00 6.25 7.50
VOLUME (liters)
\
LEGEND
o.CL-18
o . CL -12
\
0.00 1.25
2.50 3.75 5.00 6.25 7.50
VOLUME (liters)
8.75
k z
x o
• <
\ a:
\ 2
K LJ
\ \ !
\ \ ^
\ \
\
LEGEND
n =CL-'B
\
\
\
\
\
2.50 3.75 5.00 6.25
VOLUME (liters)
7.50
8.75
10.01
I/I
<
"o-
1
L
"o
0-
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o-
'o;
§
I <
\ tt
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LEGEND
o . CL - 18
o -CL-I2
1
\
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Y
\
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^
0.00 1.25
2.50 3.75 5.00 6.25 7.50
VOLUME (liters)
0.00 1.25 2.50 3.75 5.00 6.25 7.50 8.75 10.01
VOLUME (liters)
Q
Uo
O,
\
LCCCND
o =CL-I8
o-CL-12
0.00 1.25 2.50 3.75 5.00 6.25 7.50 8.75 10.01
VOLUME (liters)
Fig. A-l.
The pH, TDS, and trace element concentrations for dynamic leaching experiments with
calcined refuse.
49
-------
o «
'l? .
Q
,2?
UJ
O
.
9:
'o;
O
\ 5
1 \ UJ
\ ^ "Z.
\ * o
\\ £
\ "•-•-, *
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LEGEND
a = GL - 18
o = GL - 12
.~"\
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"9-
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a. :
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u
0
9-
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t <*
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0
LEGEND
° = GL-18
o = GL-12
\
X
\
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2.50 J.75 5.00 6.J5 7.50 , 8.75 10.01
VOLUME (liters)
0.00 1.25 2.50 J.75 5.00 6.25 7.50 8.75 10.01
VOLUME (liters)
„
o:
So,
a :
\ 1
\ ^
v §
— 'k > UJ
K :
u •
2;
I
\
\
LEGEND
o = GL - 18
o = CL-I?
\
\
\
\
\
Q
a.
on •
o
'g
•
O
o:
Uj
Z
UJ
O
UJ
K
CL
LEGEND
" = CL - 18
o = CL -12
0.00 1.25 2.50 J.'5 5.00 6.25 7.50 8.75 10.0C
VOLUME (liters)
0.00 1.25 2.50 3.75 5.00 6.25 7.50 8.75 10.0(
VOLUME (liters)
-
O-
3
a
i
0
p-
'•9:
-.
o
•4
i ft
U.
I UJ
\ &
ij
1 Q:
\ a
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1
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LEGEND
o = CL - 18
o = CL - 12
\
\
\
\
\
°O-
"g" •
Q.
-S'o:
£ '•
9:
'g;
z
o
1, A 5
\ / ^-
\ / \ 2
A / V 2
v/ \ i
'^ \
•
LICE NO
o = a - 13
o = CL - 12
\
\
\
N
\
X
0.00 i.?5 2.50 J.7b 5.00 6.25 7.50 8.75 10.01
VOI UMr (liters)
0.00 1.25 2.50 J.75 5.00 6.25 7.50 8.75 10.01
VOLUME (liters)
Fig. A-l. (cont)
50
-------
a
a.
o^
LEGEND
o ' CL - '2
\
2.50 i.75 5.00 6.25 7.50
VOLUME (liters)
8.75 10.01
LEGEND
o.CL-IS
o-CL-12
0.00 1.25 2.50 J.75 5.00 6.25
VOLUME (liters)
7.50 8.75 10.01
a
a
\
LEGEND
OoCL-18
2.50 1.75 5.00 6.25 7.50 B.75 10.01
VOLUME (liters)
£",-,
0.00
LEGEND
o-CL-tB
o = GL -12
2.50 J.'5 5.00 6.25 7.50 fl.75 10.01
VOLUME (liters)
9-
a
a •
D
^
p.
a
0
or
Ul
^ 0
\| . 1
a;
\ K
DO ^~
LECEND
o -GL-18
o-CL-12
\
\
b
0.00 l.2b ?.50 J.'b 5.00 6.?5 '.50 8.'5 10.01
VOl UML (litC'S)
0.00 1.25 2.50 J.75 5.00 6.25 7.50 8.75 10.01
VOLUME (liters)
Fig. A-l. (cont)
51
-------
0.00 1.25
2.50 3.75 5.00 6.25 7.50
VOLUME (liters)
8.75
< O
z -
LEGEND
i»CL-l8
' -GL-12
V
\
2.50 3.75 5.00 6.25 7.50
VOLUME: (liters)
~g-
^^
IT
CL.
-59-
z •
0
9-
'g
z
0
\ <
\ £
\ z
\ ^
\ £
i. \
\ \ ?
\ V
~° 0
LEGEND
o = GL - 18
o = GL-12
X
\
\
\
.
o-
'_
•
Q
Q.
a
0-
OD — :
Q_ :
'g-
•g:
1 o
\ *
\. 1
V •*-
o UJ
\ 0
V UJ
\
(X-___ tt
\ /
r
LEGEND
o = GL - 18
o = GL-12
\
\ _^
0.00 1.25 2.50 3.75 5.00 6.25 7.50 8.75 10.01
VOLUME (liters)
2.50 3.75 5.00 6.25 '.50
VOLUME (liters)
8.75
CD
Ct
LEGEND
i • CL -18
' = GL-12
0.00 1.25
2.50 3.75 5.00 6.25 7.50
VOLUME (liters)
9-
o
9-
i
i
-
9-
„
'g-
'g;
^)
\ 6
\ 5
\ £
\*—
{""
\ UJ
a Ct
\ o:
\ <
i \
LEGEND
o - CL - 18
o 0 CL - 12
\
\
B
\
\
\
\
\
O
' ' ' " ' T'CA "ft ft
. . .
VOLUME (liters)
Fig. A-l. (cont)
52
-------
o
g.
? ;
9- '
5 '
~^ •
-
^
10
_
0-
o
— g.
a :
a .
I
g-
V
(N
Z
o
or
(£
LJ
\ °
' uj
\
\ —
\
\
\
O
0.00 V?5 7.50 3.75 5
VOLUME
rr
0
i <
( or
\ 2
. UJ
' UJ
\ a
\
\ <
\
\
\
I
k,
0.00 1.25 2.50 3.75 5
VOLUME
LEGEND
o = CL-i2
»
o
00 6.25 7.50 8.75 10
(liters)
LEGEND
a - Ct - 18
o -CL-12
\
\
b
00 6.25 7.50 8.75 10
(liters)
:
a \
0- X
I": "x
X
> • >
• 1 \
9:1 \
\
t*
9-
T
a
a
.
rub-
t— "~~ ;
fv
b-
01
s-
:
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a
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or
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. Z
I UJ
1 0
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1
0.00 t.25 2.50 3.75 5
VOLUME
z
Vs «*
11 v 2
\ ^ uj
\ \ °
1 « Ul
I
\ ^ *
\
t «
0.00 1.25 250 -1.75 5
VOLUME
LEGEND
a.CL-18
o «GL-'2
LEGEND
° <• CL - <8
o-CL-12
00 6.25 7.50 8.75 10
(liters)
LEGEND
o.GL-18
o -CL-I2
^
N
\
\
\
\
\
.00 6.25 '.50 8.75 10
(liters)
0.00 1.25 2.50 3.75 5.00 6.25 7.50 8.75 «).0(
VOLUME (liters)
Fig. A-l. (cont)
53
-------
0
0-
1
1
>
-
g-
o'
fO
2
o
<
CL
UJ
Z
UJ
I O
i UJ
v K
i . ^
0 <
'
' 'tA 1 7t
LEGEND
o = CL - 18
o = CL - 1?
nn c It •» trt Q 7^ Irt
g.
:
•
-9
Q
a ;
g°9i
9-
'g:
^
\ ^
2
5
i °^- £
--. z
\ \ b
\ \ L^-1
\ \ or
\ V — o rr
\ <
\
nnn 1 7s ? sn * i*. c
LEGEND
o = CL - 18
o = GL-!2
\
V
V\
\^o
^"x.
^\.
^^
nn A ?s ? «.n R 7^ in
VOLUME (liters)
VOLUME (liters)
Fig. A-l. (cont)
-------
APPENDIX B
PRELIMINARY COST COMPARISONS FOR SELECTED ENVIRONMENTAL
CONTROL OPTIONS FOR CONTAMINATED COAL REFUSE DRAINAGE
INTRODUCTION
Our assessment of environmental control technology for Illinois Basin coal cleaning wastes has
proceeded to the point where a preliminary cost comparison of various pollution-abatement alter-
natives is in order. Cost data on many of the options are scattered throughout the literature, but
they lack a consistent time base (constant-dollar figures) and the vital relationship between solid
waste composition and pollutant concentration in the leachate. This latter information is
available in our FY 1977 Annual Report8 and provides the link for an across-the-board com-
parison.
BASE CASE
To provide a consistent basis for comparison, which could be related to existing data, three
hypothetical coal cleaning plants were postulated. For purposes of comparison, all were assumed
to have the same production capacity, ratio of waste to cleaned coal, landfill disposal area, and
annual rainfall. Also, the active life of the waste disposal site was considered to be the same. To
take advantage of published data on costs of landfill disposal, values for these parameters, other
than rainfall, were selected from the National Academy of Science/National Academy of
Engineers (NAS/NAE) Mine Waste Disposal Report (Ref. 6, pp. 78-79). They were
• production—2 070 00 tons/yr cleaned coal,
• solid waste sent to disposal pile—621 000 tons/yr,
• disposal area—250 acres, and
• active life of disposal area—20 yr.
An average annual rainfall of 35 in./yr was arbitrarily selected. The time base was selected as
March 31, 1978, the latest date for which engineering cost indexes were available.1
GENERAL GUIDELINES
Costs for complete process operations must be based on a knowledge of the size and design of
equipment, labor requirements, electric power needs, cost of consumable materials, and
material-handling requirements. The amount of information accessible for each of the seven en-
vironmental control processes considered here varied a great deal in relevance and detail. In some
instances, a so-called conceptual engineering design was required. In others, proportioning of
capacities, updating of the costs, or both was all that Was required or feasible. These variations
are explained under the heading for each process.
These guidelines were followed consistently.
(1) A capital recovery factor of 0.2588 was used to convert capital costs to an annualized basis.
This is consistent with the NAS/NAE report (Ref. 6, p. 139) and takes into account a 10%
depletion allowance and normal straight-line, 10-yr depreciation, but no investment tax
credit. If anything, it overstates the annualized capital charges.
(2) The above annualized capital charges were lumped together with all other annual charges
to calculate $/ton of coal and for discounting in calculating present value data.
55
-------
(3) All discounted cash flow computations, sinking-fund computations, etc. were performed us-
ing standard tables for 10% discrete compound interest and the appropriate time span
(usually 20 years).8
(4) A delivered cost of lime of $45.00/ton was used uniformly in all calculations. The price of
lime is a widely varying quantity, presently ranging from $32 to $42/ton in bulk quantities,
FOB.' Transportation charges vary also, but the $45/ton price is an average for hauling and
unloading over a distance of some 50 to 60 miles.
(5) For all pretreatment and pile treatment options a net weight fraction (nwf) of FeS, was
calculated from the following relationship."
[(Pyrite wf + Marcasite wf)/119.9 - 5X (Calcite wf/100)]X 119.9 = nwf FeS2. (B-l)
The waste from hypothetical Plants A, B, and C, corresponding to Illinois Basin Plants A,
B, and C, had the following net weight fractions of FeS8: 0.184, 0.260, and 0.294, respective-
ly. Lime requirements were calculated by multiplying the above figures by 0.937; this
yielded tons of lime required for complete neutralization of the acid generated by these sul-
fides in one ton of waste.
DATA SOURCES AND COMPUTATIONAL PROCEDURES
Alkaline Neutralization of Coal Refuse Drainage and Clarification of Effluent
Lime neutralization cost data for acid drainages appear in various prior reports, one of which is
the Brown's Creek, Lost Creek Pollution Abatement Study (Ref. 10, p. 83). However, the infor-
mation is insufficient to permit wide variation in the parameters of effluent flow and iron con-
centration in determining plant capital and operating costs. Therefore a plant design based on a
reactor-clarifer (Ref. 11, pp. 19-51), which returns the slurry precipitate to the active pile, was
evaluated. Cost was estimated from the clarifier settling area and 1955 standard cost data (Ref.
12, p. 69) that was updated according to standard proportioning procedures.*
Because it was thought desirable to evaluate a wide variety of input data and system
parameters, a computer program was prepared to determine the size and cost of a neutralizer-
clarifier for a variety of leaching conditions from piles of coal cleaning wastes. All costs above the
base landfill disposal case are calculated, with the exception of costs for retaining, impounding,
and channeling the pile effluent from rainwater percolation. These must be considered in any
posttreatment process but are very site specific so that no realistic "average figure" seems credi-
ble. The following paragraphs serve as documentation for the computer program called LAND-
FIL (listed in Appendix E), as well as detailing design and cost calculation methods and assump-
tions for the lime neutralization posttreatment.
Input data to the computer program are (1) parts per million of Fe+> and Fe+> in the effluent;
(2) annual rainfall in the area of the pile, in inches; (3) area of the active pile, in acres; and (4)
fraction of rainfall absorbed by the pile. This last figure was assumed to be 0.9999 for an un-
covered pile and 0.3333 for a soil-covered, grassed-over pile.
Lime requirement was calculated from stoichiometry assuming 1.5 moles of acid generated per
mole of iron in the effluent. This is a reasonable average figure according to the literature (Ref.
14, p. 5). However, the calculation was made more conservative (that is, inclined in the direction
'The standard proportioning procedure was to multiply the standard cost by the ratio (March 1978 value):(year of com-
putation value) of the appropriate category in the Chemical Engineering Plant Cost Index or the Marshall & Swift
Equipment Cost Index.'-"
56
-------
of higher lime use) by using Ca(OH)s for the weight of lime in the neutralization reaction. The re-
sulting figure of 1.2406 X 10"4 pounds of lime per cubic foot of effluent per ppm of iron was used in
the calculation of lime demand for each set of initial conditions.
Clarifier area was calculated from the Coe and Clevenger formula" using the largest area
calculated from settling-rate data. The solids were assumed to settle to 12% of the original
volume before being removed as underflow from the clarifier. The rationale and method of
calculation are explained in detail in Ref. 15. Total dissolved solids were assumed to be eight
times the iron concentration and to this was added the lime requirement for calculation of solids
in clarifier underflow. The cost of the clarifier was determined by linearizing the two major por-
tions of the standard cost curve (Ref. 12, p. 69). This approximation is reasonably good in the
ranges 100-1000 sq ft and 1000-8000 sq ft of clarifier surface. For output in excess of 8000 sq ft the
calculated cost is clearly too low, especially because more than one clarifier would be needed in
such high ranges. However, in the worst case of active pile application studied, the requirement
of 8000 sq ft was not reached until after seven years had passed so that discounting the future cost
of additional clarifiers tends to offset the low-cost prediction.
Clarifier underflow is returned to the active pile by a pipeline assumed to be 1500 ft in length
with an effective hydraulic head of 250 psi. The computer program sizes the pipe and pump
depending on flow volume and calculates the cost of pipe, pump, and the pumping energy ac-
cording to standard formulas using a maximum velocity of 1 ft/s* (see Ref. 11, pp. 6-45 and Ref.
16, pp. 92 and 177).
Operating costs consisted of labor costs plus power costs. Power was calculated for the clarifier
and the slurry pump. Labor was estimated at $40.00/day for a part-time operator/maintenance
man; this estimate may be too low.
Output of program LANDFIL provides information on the calculated lime requirement in
tons/day, clarifier area in sq ft, annualized capital cost in dollars, and annual operating cost (ex-
clusive of lime) in dollars. As previously mentioned, the output also included annual cost of lime.
The program was run for each of the 20 yr for each of the three hypothetical plants, using
laboratory data on ppm of iron versus the total water-to-waste ratio as input. For year one, a 12.5-
acre uncovered pile is assumed. For years 2-20, covered piles increasing by 12.5 acres per year are
calculated and first year lime costs are added because there is always 12.5 acres of open pile being
worked. This provides a precise lime cost and slightly understates the annual operating cost.
Average figures for each of the four 5-yr periods were calculated. Finally, a sinking-fund pay-
ment, applied to each year of operation, was calculated from the average cost for the last 5 yr
(highest average annual costs). The sinking fund was calculated at a 10% rate of return to
provide the necessary trust fund corpus at the end of the 20-yr active live. Annualized total cost
and cost per ton of cleaned coal were obtained by summing annualized capital cost, annual
operating cost, annual lime cost, and annual sinking-fund payments.
Ion Exchange and Reverse Osmosis Costs to Treat Refuse Drainage
Time did not permit careful cost analysis of more expensive reverse osmosis and ion-exchange
posttreatment options. However, Source 62062 in the Brown's Creek and Lost Creek study (see
Ref. 11, pp. 83-87) was found to be roughly comparable to Plant C in effluent composition,
though differing in flow volume. For a preliminary comparison of costs, it was deemed sufficient
to use the ratios of costs derived from the earlier study. The cost estimates for these two processes
should be considered only as very crude approximations.
'Through errors, the velocity and cost were calculated for different wall thicknesses of pipe. Velocity was calculated for
thin-wall 5s-pipe, and cost was calculated for the thicker wall 40 st-pipe corresponding to the assumed pressure. In some
instances this may result in a pumping energy cost that is 5 to 10% too low. This cost is only a small proportion of the
total cost however.
57
-------
Codisposal of Lime and Coal Refuse
Costs for directly adding 25 and 50% of stoichiometric amounts of lime needed if all the pyrite
-was converted to acid were calculated on delivered lime cost only. Because of its fine particle size,
it was assumed that the lime would not add appreciably to the bulk of the pile but would fill the
voids between the waste material. Only a negligible amount of energy and labor above that
already devoted to pile construction would seem to be required. There is good theoretical reason,
based on the comparatively small exposed surface of pyrites in coal waste piles, to believe that
even less lime may serve to deactivate or neutralize the acid-leaching processes.
Codisposal of Fly Ash and Coal Refuse
Capp and Adams have reported successful attempts to reclaim the surface of spoil banks and
coal waste piles for vegetative propagation by large additions of alkaline, power-plant fly ash."
The amount varied with conditions of the waste and overburden, but the authors stated that the
fly ash they used had about one-twelfth the neutralizing capacity of limestone. This unmodified
fly ash therefore had one-eighteenth the neutralizing capacity of lime. We also considered
limestone-modified fly ash, which was assumed to have one-twelfth the neutralizing power of
lime.
Two scenarios for fly ash use were considered. In the first, the power plant was located 15 road
miles from the coal cleaning plant; in the other it was within 1500 ft of refuse landfill. In both
scenarios, it was assumed that no market existed for the fly ash. It was assumed that (based on
the base-case costs) the cost to the power plant for disposal to landfill was $1.50/ton of fly ash.
Truck loading charges were set at $2.00/ton for the first scenario. To this was added a hauling
charge of $1.80/ton, an unloading charge of $0.50/ton, and an additional operating cost of
$0.50/ton; a total of $4.80/ton of fly ash added to the pile for the first scenario. For the second
scenario, it was assumed that the power plant would deliver the fly ash with its own conveyer
system to the landfill area, without charge. The only charge would be $0.50/ton of fly ash for ad-
ditional operating expense at the landfill. This results from the very large additional volume of
material that must be distributed and compacted. More machines, fuel, and labor are necessarily
required for any of the fly-ash scenarios than for straight wastefill. Calculations of the cost were
made only for one level of addition, namely, fly ash equivalent in neutralizing power to direct ad-
dition to the pile of 25% of the theoretical amount of lime needed.
Codisposal of Local Soils With Coal Refuse Materials
The model system used was a soil with alkalinity corresponding to 5% by weight of CaCO,. It
was assumed that the worst case of oxidation before disposal would be 10% of the FeS8 content.
Calculations were made for sufficient soil to negate 11% oxidation. For the three plants (A, B,
and C) in the study the mass-of-soil per mass-of-waste ratios were 0.678,0.957, and 1.082, respec-
tively. In other words, burying coal cleaning waste from Plant A would require 0.678 tons of a 5%
alkaline soil to neutralize any acid formed before disposal and to immobilize or attenuate any
further reaction or release of metal ions from one ton of waste. The costs would be somewhat
lower if the soil was more highly alkaline; however, a certain minimum amount would be required
to attain the densification and compaction that is deemed essential to this process. Therefore, the
Plant A costs given are probably about as low as one might expect for any plant, regardless of the
soil alkalinity.
58
-------
Mixing soil with waste during the disposal process would have the advantage of filling the voids
between the larger refuse particles with small particles of soil. On a volume basis, the theoretical
maximum ratio required for this purpose would be approximately 0.68 soil/waste. In practice,
this theoretical maximum would never be reached, so very good densification should be possible
with a 50 to 75 wt% addition. One could expect the permeability of the resulting mixture to be
much lower than that of normally compacted waste alone. The combination of the neutralizing
and immobilizing power of the soil, together with the lowered permeability, could be sufficient to
prevent significant ground-water pollution.
Calcining to Immobilize Refuse Contaminants
Pretreatment by calcining to approximately 1000°C is an attractive method for immobilizing
the labile contaminants in coal refuse materials. The landfill requirements and cost would not
change much from those of uncalcined refuse materials because the calcined mass and scrubber
slurry (sulfur dioxide removal from the calciner effluent) would occupy about the same disposal
volume as the original coal cleaning waste. Another important point is that an amount of lime
proportional to the FeS8 present in the refuse would be required for sulfur dioxide removal from
the stack gases. Optionally, half the lime in the scrubber may be replaced with limestone.
For calculational purposes, we assumed that the heat of combustion of the residual coal and
the pyrite and marcasite constituents in the refuse would be sufficient to maintain operating
temperature in the kiln once the temperature was reached using auxiliary fuel to heat the kiln.
The assumption was based upon the high thermal efficiency of modern kilns but may not hold if
the heat of fusion of the glassy materials formed is substantial.
Capital costs were approximated only roughly. Based on 20 days/yr of operation, the
throughput of waste would require three rotary kilns of commercial maximum size for Plant A
and four for Plants B and C. Baghouse and sulfur dioxide scrubbers account for the remainder of
the major equipment items. Capital cost was estimated at $7 000 000 for Plant A, $8 500 000 for
Plant B and $9 000 000 for Plant C. However, these costs could be 50% or more low without
significantly affecting the ultimate cost figures because the lime for sulfur dioxide neutralization
is two-thirds or more of the total cost. However, if a combined limestone/lime neutralization
system is used, annual and unit costs may be significantly reduced.
Calcining costs depend on the proportion of sulfur immobilized in the residue and also upon
calcining temperature. The predicted costs given are the minimum that might be expected. They
could be 50 to 100% higher, depending upon the ultimate process chosen.
Water Flow Through Waste Landfill Pile
The magnitude of the annual volume of leach water from the landfill may be observed from the
calculated data in Table B-I. To compare this with our laboratory column teachings, consider
that 4 129 125 tons of water are predicted to flow through the pile by the 20th yr and 12 420 000
tons of water will have accumulated in the pile, which means that the cumulative flow in the 20th
yr is equivalent to only 220 mi of leach water having passed through a laboratory column packed
with 1500 g of coal cleaning waste. After the pile is complete, the cumulative flow increases at a
rate of 17.7 mt/yr so that the two-liter mark, a point at which we find the leachate still loaded,
corresponds to about 100 yr after the pile has ended its active life.
59
-------
Lime/Waste Ratio Required for Various Control Processes
The lime/waste ratio for various processes is shown in Table B-H Note that the posttreatment
will require considerable additional lime beyond the 20-yr active life, but this amount has not
been calculated. The amount of fly ash needed for codisposal neutralization of waste acidity is
given in Table B-ffl.
CONTROL OPTION COSTS
Tables B-IV, B-V, and B-VI present total cost data for 8 control processes and 13 total varia-
tions, in different forms. Table B-IV compares each on a basis of unit cost in dollars per ton of
cleaned coal shipped. Table B-V presents the same data in terms of annual coats over the 20-yr
working life of the disposal area. Costs in Tables B-IV and B-V include charges for treatment re-
quired after the active life of the pile has expired. Table B-VI compares the options in terms of
net present value of cost, calculated at 10% cost of capital. To the person unfamiliar with the ter-
minology of finance, these figures may be considered as the total number of dollars that would
need to be paid in a lump sum in 1978 to assure pollution abatement for the life of the project
(and beyond, if necessary). Figures in all three of these tables do not include the basic cost of
landfill, which is indicated on each table, or the cost of sealing the disposal site.
TABLE B-I
LANDFILL GROWTH AND MASS FLOW OF WATEK THROUGH WASTE
PILE DURING 20 YR ACTIVE LIFE OF PILE-
Flow ThrouL'h Pile Cumula
Year
1
•_>
:t
•1
r,
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
(Tons of
Uncovered
49550
49550
49550
49 550
49550
49550
49550
49 550
49550
49550
49550
49550
49500
49550
49550
495.50
49550
49550
49550
49550
Water)
Covered
0"
16517
113 033
49 550
66066
82 583
99099
115616
132 132
148649
165 165
181 682
198 198
214715
231231
247 748
204 264
280781
297 297
313814
Annual Total
Flow (Ions)
49 5.50
66 066
82 583
99 (199
115616
132 132
148649
105 165
181 682
198 198
214715
231 231
247 748
264 264
280781
297 297
313814
330 330
346 847
363 363
Water Flow
(tons)
49 550
115616
198 198
297 297
412913
545045
693 693
&58 858
1 040 540
1 238 738
1 453 452
1 684 (i83
1932431
2 1966!)5
2 477 475
2 774 772
3 088 586
3418916
3 765 762
4 129 125
Waste
(tons)
621 000
1 2-12 000
1 863 000
2 484 000
3 105000
3 726 000
4 347 000
4 968 OIK)
5 589 000
6210000
683 1000
7452000
807301X1
8 694 000
9315000
9 936 (MX)
10557000
11 178000
11799000
12420000
live Data
Water/Waste
Mass Ratio
0.0797!)
0.09309
0.10639
0.11968
0.13298
0.14628
0.15958
0.17288
0.18618
0. 19947
0.21277
0.22607
0.23937
(1. 25267
0.26597
0.27920
0.29256
0.30586
0.31916
0.33246
Liters/1. 5kg
0.0532
0.0621
0.0709
0.0798
0.0887
0.0975
0.1064
0.1153
0.1241
0.1330
0.1418
0.1507
0.15%
0.1684
0.1773
0.1862
0.19.50
0.2039
0.2128
0.2216
•Assumes 35 in.AT annual rainfall and '250 acres ultimate landfill area.
•No covered portion in first year.
60
-------
TABLE B-II
LIME REQUIREMENTS FOR VARIOUS
TREATMENTS OF COAL WASTE
Process
TON OF LIME/TON OF WASTE
Plant A Plant B Plant C
Calcining-Lime Neutralization
Calcining-Lime and Limestone Option
25% Lime to Pile
Lime Neutralization of Drainage—1st yr.
Lime Neutralization of Drainage—2nd yr.
Lime Neutralization of Drainage—10th yr.
Lime Neutralization of Drainage—20th yr.
0.1722
0.0862
0.0431
0.0003
0.0004
0.0010
0.0015
0.2433
0.1218
0.0609
0.0019
0.0025
0.0090
0.0229
0.2571
0.1377
0.0689
0.0001
0.0001
0.0004
0.0008
TABLE B-III
FLY ASH DEMAND REQUIREMENTS FOR
CODISPOSAL TREATMENT OF COAL WASTE8
TON OF FLY
ASH/TON OF WASTE
Type of Fly Ash Plant A Plant B Plant C
Unmodified 0.7758 1.0962 1.2402
Limestone Modified 0.5172 0.7308 0.8268
•Equivalent to case where 25% of the theoretical amount of lime is used.
61
-------
TABLE B-IV
COSTS OF VARIOUS DRAINAGE TREATMENT/PREVENTION PROCESSES
Process
Pretrcatment
Calcining-(60% Fixation of S02)
Calcining-( Li me- Limestone S02system)
Codisposal
25% of Theoretical Lime Requirement
50% of Theoretical Lime Requirement
Unmodified Fly Ash (Equivalent to 25% Lime)
(Mine 15 mi. from power plant)
Unmodified Fly Ash (Equivalent to 25% Lime)
(Mine adjacent to power plant)
Limestone-Mod. Fly Ash (Equivalent to 25% Lime)
(Mine 15 mi. from power plant)
Limestone-Mod. Fly Ash (Equivalent to 25% Lime)
(Mine adjacent to power plant)
Local Soils and Subsoils (Equivalent to 4% Lime)
Effluent Treatment
Lime Precipitation/Clarification
(First live years of active pile)
Lime Precipitation/Clarification
(Last live years of 20-yr active pile)
Reverse Osmosis
Ion Exchange
•All costs would lie added lo a basic landfill disposal cost of
$0.-Hi/ton of cleaned coal shipped. All costs are adjusted to March
1978 value. See text for assumptions and qualifications regarding
cosi s.
"Major cost is lor lime or limestone in scrubbing system.
''Major cost is lor transporting the fly ash. which is assumed lo be
free.
"Highly active waste.
Dollars/Ton of Cleaned Coal"
Plant A Plant B Plant C
3.30"
2.14"
0.64
1.28
3.72C
0.39
2.48°
0.25
0.81
0.08
0.10
4.44b
2.80b
0.90
1.81
5.26C
0.55
3.5 lc
0.36
1.15
0.83d
1.11"
4.94b
3.08"
1.02
2.05
5.95C
0.62
3.97C
0.41
1.30
62
-------
TABLE B-V
ANNUAL COSTS OF VARIOUS DRAINAGE
TREATMENT/PREVENTION PROCESSES
Process
Annual Cost ($k)/2.07 MM
Annual Tons of Cleaned Coal8
Plant A Plant B Plant C
Pretreatment
Calcining-(60% Fixation of SO,) 6826 9201 10219
CalcininK-(Lime-Limestone SO, system) 4420 5802 6375
Codisposal
25% of Theoretical Lime Requirement 1326 1872 2118
f)0% of Theoretical Lime Requirement '2651 .'i 744 4 2.'!4
Unmodified Fly Ash (Equivalent to 25% Lime) 2312 3268 3G97
(Mine 15 mi. from power plant)
Unmodified Fly Ash (Equivalent to 25% Lime) 240 340 385
(Mine adjacent to power plant)
Limestone-Mod. Fly Ash (Equivalent to 25% Lime) 1542 2178 2465.
(Mine 15 mi. from power plant)
Limestone-Mod. Fly Ash (Equivalent to 25% Lime) 161 227 257
(Mine adjacent to power plant)
Local Soils and Subsoils (Equivalent to 4% Lime) 1677 2380 2681
Effluent Treatment
Lime Precipitation/Clarification 172 1 725 106
(First five years of acti%'e pile)
Lime Precipitation/Clarification 202 2292 121
(I ,ast five years of 20-yr active pile)
Reverse Osmosis 407
Ion Exchange 602
•The linsic landfill disposal cost, adjusted from 1974 to 1978 dol-
lars using the Marshall and Swift Equipment Index for Mining, is
S()(i2 000 per year. All costs are adjusted to March 1978 values.
See text for assumptions and qualifications regarding costs.
63
-------
TABLE B-VI
NET PRESENT VALUE OF COSTS FOR VARIOUS DRAINAGE
TREATMENT/PREVENTION PROCESSES
Net Present Value of Cumulative Cost"
($k)
Process
Plant A Plant B Plant C
Pretreatment
Galcining-(60% Fixation of S02)
Calcining-(Lime-Limestone S02 system)
Codisposal
25% of Theoretical Lime Requirement
50% of Theoretical Lime Requirement
Unmodified Fly Ash (Equivalent to 25% Lime)
(Mine If) mi. from power plant)
Unmodified Fly Ash (Equivalent to 25% Lime)
(Mine adjacent to power plant)
Limestone-Mod. Fly Ash (Equivalent, to 25% Lime)
(Mine 15 mi. from power plant)
Limestone-Mod. Fly Ash (Equivalent to 25% Lime)
(Mine adjacent to power plant)
Local Soils and Subsoils (Equivalent to 4% Lime)
Effluent Treatment
Lime Precipitation/Clarification
Reverse Osmosis
Ion Exchange
"1'resent value of basic landfill operation, adjusted In March I9T8
value, is $8 187 000. All costs arc adjusted to March 1978 value.
See text for assumptions and qualifications regarding costs.
58 086
37614
11 275
23 550
19679
2 050
13 120
1 367
14268
1 568
79 299
49371
15932
31 865
27 807
2 897
18539
1 931
20 257
15981
86 965
54 251
18016
36 032
31 460
3277
20 973
2 185
22811
64
-------
APPENDIX C
COLUMN LEACHING STUDIES OF LIMESTONE/REFUSE MIXTURES
TABLE C-I
EXPERIMENT IDENTIFICATION FOR DYNAMIC LEACHING
STUDIES OF LIMESTONE/REFUSE MIXTURES
Experiment No. Limestone Location
Sample8
C.L-12
CL-14
CL-l.r>
CL-lfi
(None - Control)
Intermixed
layered at outlet
Layered at inlet
Layered at outlet
1500 g re fuse
1300 K refuse
220 g limestone
1300 g refuse
229 g limestone
1300 g refuse
221 g limestone
1300 g refuse
220 g limestone (-20 mesh)
"Minus :t/8 inch Illinois Basin Plant B refuse used throughout;
minus H/8 inch limestone unless noted.
65
-------
TABLE C-I1
ANALYSES FOR DYNAMIC LEACHING STUDIES OF
LIMESTONE/REFUSE MIXTURES
Experiment No. GL-12
Parameter*
Vol (t)
pH
TDS(%)
Na
Mg
Al
K
Ca
Sc
Ti
V
Cr(M(!/*)
Mn
Fe
Co
Ni
Cu
Zn
Ga
As
Br
Rb
Mo
Ag
Cd(ng//)
Cs
La
Ce
Sm
Eu
Tb
Dy
Yb
Lu
Hf
Ta
W
Pb(ng/l)
Th
U
1
0.040
1.3
8.63
25
500
1600
51
530
3.0
<0.4
1.44
790
130
15000
36
51
10
76
<0.2
7.9
<0.04
<2
in Mtl'ni/ unless otherwise slated.
6\\'nier tlmv \vn> stopped ot this point, air was passed through the column lor -1 uk. then UMUT l
66
-------
Sample No.'
TABLE C-lll
ANAI.YSKS FOR DYNAMIC l.KACHINC.1 STUDIKS (IK
LIMESTONK/HEKUSE MIXTURES
Experiment No. GL-14
6 8 11 18 19 21
25
26
29
30
Vol (1)
pH
TDS (%)
Na
Mg
Al
K
Ca
Sc
Ti
V
CrOig/i)
Mn
Fe
Co
Ni
Cu
Zn
Ga
As
Br
Rb
Mo
Ag
Cd(*ig/l)
CB
La
Ce
Sro
Eu
Tb
Dy
Yb
Lu
Hf
Ta
W
PbUig/l)
Th
U
0.085
2.5
4.72
IB
630
810
0.37
590
1.4
' <0.4
0.48
. 320
48
8100
26
44
4.1
55
<0.2
0.40
<0.04
<2
<0.1
<0.01
320
<0.04
0.47
1.20
<0.02
0.10
<0.1
0.21
0.14
0.02
<0.02
<0.05
<0.04
30
0.47
0.27
0.195
2.6
4.62
12
430
730
1.2
730
1.1
<0.4
0.37
180
49
8500
24
43
2.4
49
<0.2
0.06
<0.04
<2
<0.1
<0.01
210
<0.04
0.93
<0.08
0.02
0.07
<0.1
0.18
0.10
0.03
<0.02
<0.05
<0.04
12
0.36
0.23
2.260
2.9
0.52
1.3
31
9
0.5
630
<0.01
<0.4
<0.01
4.5
4
660
1.8
3.1
<0.1
3.5
<0.2
<0.02
<0.04
<2
<0.1
<0.01
18
<0.04
0.10
<0.08
<0.02
0.08
<0.1
0.17
<0.03
<0.01
<0.02
<0.05
<0.04
9
<0.02
<0.0l
3.000
4.4
0.34
1
19
<0.5
0.5
570
<0.01
<0.4
<0.01
<5
2.4
305
0.5
1.4
<0.1
1.9
<0.2
<0.02
<0.04
<2
<0.1
<0.01
4.8
<0.04
<0.5
<0.08
<0.02
<0.01
<0.1
0.01
<0.03
<0.01
<0.02
<0.05
<0.04
<5
<0.02
<0.01
. 6.090
7.4
0.25
0.9
3.2
<0.5
0.7
550
<0.01
<0.4
<0.01
<6
0.28
3
<0.09
<0.23
<0.1
0.23
<0.2
<0.02
<0.04
<2
<0.1
<0.01
0.28
•C0.04
<0.5
<0.08
<0.02
<0.01
-------
TABLE C-IV
ANALYSES FOR DYNAMIC LEACHING STUDIES OF
LIMESTONE/REFUSE MIXTURES
Experiment No. GL-15
Sample No.
11 .
18
19
22
27
28
Vol U)
pH
TDS(%)
Na
Mg
Al
K
Ca
Sc
Ti
V
Cr(>ig//)
Mn
Fe
Co
Ni
Cu
Zn
Ga
As
Br
Rb
Mo
Ag
CdW/)
Cs
La
Ce
Sm
.Eu
Tb
Dy
Yb
Lu
Hf
Ta
W
Pb(ng/t)
Th
U
0.090
2.4
6.08
30
470
1000
0.4
920
1.8
<0.4
0.70
330
60
10400
30
50
7
70
<0.2
0.31
<0.04
<2
<2
<0.0l
330
<0.04
<0.5
3.2
0.06
0.17
<0.1
0.20
<0.03
0.03
<0.02
<0.05
<0.04
40
0.74
0.34
0.200
2.6
4.97
16
1940
590
48
970
1.0
<0.4
0.53
230
54
9200
27
48
3.2
54
<0.2
<0.02
<0.04
<2
<1
<0.01
200
<0.04
<0.5
1.1
0.31
0.11
<0.1
0.20
0.13
0.24
<0.02
<0.05
<0.04
170
0.43
0.21
1.650
2.6
0.43
0.8
24
40
3.2
370
0.08
1.11
0.09
24
2.4
610
1.6
2.4
0.32
3.2
<0.2
<0.02
<0.04
<2
<2
<0.01
16
<0.04
<0.5
0.25
<0.02
0.02
<0.1
0.02
<0.03
<0.01
<0.02
<0.05
<0.04
16
0.03
0.02
3.825
4.3
0.34
1
11
<2
5
830
<0.01
<0.4
<0.01
<16
1.5
180
1.3
1
<0.3
0.8
<0.2
<0.02
<0.04
<2
<2
<0.01
16
<0.04
<0.5
<0.08
<0.02
<0.01
<0.1
<0.01
<0.03
<0.01
<0.02
<0.05
<0.04
16
<0.02
<0.01
7.020
5.8
0.12
0.4
4
<0.4
2
260
<0.01
<0.4
<0.01
<4
0.4
66
<0.08
0.3
<0.1
0.3
<0.2
<0.02
<0.04
<2
<2
<0.01
0.8
<0.04
<0.5
<0.08
<0.02
<0.01
<0.1
<0.01
<0.03
<0.01
<0.02
<0.05
<0.04
<8
<0.02
<0.01
U.lW
6.2
0.05
0.4
2
<0.4
2
96
<0.01
<0.4
<0.01
<1
0.2
22
<0.09
<0.2
<0.1
0.2
<0.2
<0.02
<0.04
<2
<2
<0.01
<0.09
<0.04
<0.5
<0.08
<0.02
<0.01
<0. 1
<0.01
<0.03
<0.01
<0.02
<0.05
<0.04
<9
<0.02
<0.01
14.395
3.6
0.94
4
24
39
8
680
0.03
<0.4
<0.01
<8
5
1400
2
4
0.5
8
<0.2
0.02
<0.04
<2
<2
<0.01
8
<0.04
<0.5
0.43
0.05
0.02
<0.1
0.01
<0.03
<0.01
<0.02
<0.05
<0.04
16
<0.02
0.01
14.915
4.7
0.77
2
17
0.8
7.5
780
<0.01
<0.-1
<0.01
<8
3
1100
2
2.5
<0.2
2
<0.2
<0.02
<0.04
<2
<2
<0.01
8
<0.04
<0.5
<0.08
<0.02
<0.01
<0.1
0.05
<0.03
<0.01
<0.02
<0.05
<0.04
<16
<0.02
<0.01
20.050
5.4
0.02
0.4
1.5
0.7
2
100
<0.01
<0.4
<0.01
<7
0.2
7
<0.2
<0.4
<0.2
<0.04
<0.2
<0.02
<0.04
<2
<2
<0.01
0.2
<0.04
<0.5
<0.08
<0.02
<0.01
<0.1
<0.01
<0.03
<0.01
<0.02
<0.05
<0.04
<15
<0.02
<0.01
25.135
5.8
0.03
0.5
1
0.5
3
100
<0.01
<0.4
<0.01
<5
0.2
5
<0.1
<0.3
<0.1
<0.03
<0.2
<0.02
<0.04
<2
<1
<0.01
0.1
<0.04
<0.5
<0.08
<0.02
<0.01
<0.l
<0.01
<0.03
<0.01
<0.02
<0.05
<0.04
<10
<0.02
<0.01
•V»)ue.s in ti%Jml unless otherwise staled.
B\\'nier (low wns slopped at thi? point, nir wn*. passed i
the column lor I \
68
-------
TABLE C-V
ANALYSES FOR DYNAMIC LEACHING STUDIES OF
LIMESTONE/REFUSE MIXTURES
Experiment No. GL-16
Sample No.*
Vol U)
pH
TDS(%)
Na
Mg
Al
K
Ca
Sc
Ti
V
Cr^g/J)
Mn
Fe
Co
Ni
Cu
Zn
Ga
As
Br
Rb
Mo
Ag
CA(itfi/t)
Cs
La
Ce
Sm
Eu
Tb
Dy
Yb
Lu
Hf
Ta
W
Pb(xg/*)
Th
U
0.100
1.5
6.27
28
370
1100
38
640
2.35
<0.4
0.99
570
38
10700
24
40
7
56
<0.2
5.8
<0.04
<2
0.2
<0.01
300
<0.04
1.5
2.2
0.08
0.20
0.05
0.61
0.30
0.06
<0.02
<0.05
<0.04
900
1.1
0.38
0.300
1.5
5.88
17
350
1100
33
650
2.1
<0.4
0.80
660
37
7200
25
41
5
58
<0.2
<0.04
<2
0.6
<0.01
410
<0.04
1.3
2.6
0.68
0.19
0.10
0.49
0.15
0.05
<0.02
<0.05
<0.04
640
1.1
0.31
1.510
2.2
0.74
2.3
46
110
11
220
0.12
<0.4
0.28
76
5
1200
3
5
0.23
7.6
<0.2
0.39
<0.04
<2
<1
<0.01
34
<0.04
<0.5
0.37
0.03
0.03
<0.1
0.04
<0.03
<0.01
<0.02
<0.05
<0.04
53
0.03
0.06
2.815
2.5
0.34
2
18
36
4.5
122
0.02
<0.4
0.11
42
2
540
1
2
<0.06
3
<0.2
0.28
<0.04
<2
<1
<0.01
15
<0.04
<0.5
<0.08
<0.02
0.01
<0.1
0.04
<0.03
<0.01
<0.02
<0.05
<0.04
36
<0.02
0.01
1 Values in fig/ml unless otherwise stated.
69
-------
TABLE C-VI
ANALYSES FOR DYNAMIC LEACHING STUDIES OK
LIMESTONE/REFUSE MIXTURES
Experiment No. GL-17
Sample No.'
13
18
Vol(/)
PH
TDS(%)
Na
Mg
Al
K
Ca
Sc
Ti
V
CrOig//)
Mn
Fe
Co
Ni
Cu
Zn
Ga
As
Br
Rb
Mo
Ag
CdUg/J)
Cs
La
Ce
Sm
Eu
Tb
Dy
Yb
Lu
Hf
Ta
W
Pb(Mg/J)
Th
U
0.100
3.5
4.01
43
710
130
71
600
0.40
<0.4
<0.01
43
54
7800
27
43
<0.1
49
<0.2
0.04
0.12
<2
<1
<0.01
140
<0.04
<0.5
<0.08
<0.02
0.03
<0.1
0.24
<0.03
<0.01
<0.02
<0.05
<0.04
27
<0.02
0.07
2.040
3.8
0.51
2
39
<0.3
3
600
<0.01
<0.4
<0.01
21
5
480
2.4
3
<0.1
3
<0.2
<0.02
<0.04
<2
<1
<0.01
12
<0.04
<0.5
<0.08
<0.02
<0.01
<0.1
<0.01
<0.03
<0.01
<0.02
<0.05
<0.04
9
<0.02
0.01
3.530
4.5
0.31
1
10
0.5
10
630
<0.01
<0.4
<0.01
<5
2
150
0.5
1
<0.1
1
<0.2
<0.02
<0.04
<2
<1
<0.01
4
<0.04
<0.5
<0.08
<0.02
<0.01
<0.1
<0.01
<0.03
<0.01
<0.02
<0.05
<0.04
-
<0.02
<0.01
5.660
5.4
0.26
0.8
3
<0.3
2
580
<0.01
<0.4
<0.01
<3
0.6
61
0.3
0.3
<0.06
0.2
<0.2
<0.02
<0.04
<2
<1
<0.01
0.3
<0.04
<0.5
<0.08
<0.02
<0.01
<0.1
<0.01
<0.03
<0.01
<0.02
<0.05
<0.04
-
<0.02
0.08
9.435
6.5
0.19
1
4
<0.1
1.5
510
<0.01
<0.4
<0.01
<1
0.1
<0.5
<0.02
<0.05
<0.02
<0.01
<0.2
<0.02
<0.04
<2
<0.2
<0.01
<0.02
<0.04
<0.5
<0.08
<0.02
<0.01
<0.1
<0.01
<0.03
<0.01
<0.02
<0.05
<0.04
<5
<0.02
<0.01
1 1 .590
7.2
0.13
1
3
<0.1
1.5
320
<0.01
<0.4
<0.0l
<1
0.04
<0.5
<0.02
<0.05
<0.02
<0.01
<0.2
<0.02
<0.0-1
<2
<0.2
<0.01
0.03
<0.04
<0.5
•C0.08
<0.02
<0.01
<0.1
<0.01
<0.03
<0.01
<0.02
<0.05
<0.04
<5
<0.02
<0.01
Values in us/ml unless otherwise stated.
70
-------
s.
X
LEGEND-
° =GL-12
o = CL-u
« = GL-15
• =GL-16
• -GL-17
9.0 12.0 15.0
VOLUME (liters)
18.0
21.0
a
5;
lECEUD
=CL-I2
« -CL-16
• =CL-17
\
6.0 9.0 12.0 15.0 18.0
VOLUME (liters)
24.C
LCCENO
o-GL-12
«=GL-16
• -GL-17
6.0 9.0 12.0 15.0 18.0
VOLUME (liters)
LEGEND
a -GL-12
o = Cl-U
» - GL -15
• =CL-16
• -GL-17
6.0 9.0 12.0 15.0
VOLUME (liters)
6.0 9.0 12.0 15.0
VOLUME (liters)
O-
"s-
n
CL.
O
(_)
0
O
Je
'o
p
L
t c
vV *-
'v\ 2
\%>. ^
VVV...F 5
H/ "-. ^
\ '"•-. -
"*
Xv -"""" "°
* ' * •
LEGEND
o- GL-12
o -GL-14
• -GL-15
.-CL-I6
»-CL-17
k
^^*^tJ
1
V,
\ '••-.
\ \
\ \
1__^ '""••
' ' *
VOLUME (liters)
Fig. C-l.
The pH, TDS, and trace element concentrations for dynamic leaching experiments with
limestone/refuse mixtures.
71
-------
, \
LECCNO
• = CL-15
« =CL-16
• =GL-I7
6.0
9.0 U.O 15.0
VOLUME (liters)
LEGEND
D.GL-I?
o «CL-K
« = CL-15
. = CL-I6
» = CL-17
6.0 9.0 12.0 15.0 18.0
VOLUME (liters)
210
LECCNQ
= CL-1«
= GL-15
= GL-16
LCCCNO
o =GL-12
o = CL-M
• = GL -15
« =CL-I6
• =CL-i;
6.0 9.0 l?.0 15.0
VOLUME (liters)
6.0 9.0 12.0 15.0
VOLUME (liters)
21.0
IECENQ
=GL-12
= CL - »
- CL -15
=CL-I6
0.0 JO 6.0 9.0 12.0 15.0 180 21.0 2<.C
VOLUME (liters)
LECCNO
o -CL-12
o = CL -14
0.0 J.O 6.0 9.0 12.0 15.0 18.0 71.0 2<.C
VOLUME (liters)
Fig. C-l. (cont)
72
-------
\
LEGEND
o=GL-12
ooGL-14
.oGL-15
• =CL-I6
• -CL-17
3.0
6.0 9.0 12.0 15.0
VOLUME (liters)
0.0
a —
\
LEGEND
o-GL-12
o=CL-14
«=CL-I5
• -CL-16
• -GL-I7
0.0
9.0 12.0 15.0
VOLUME (liters)
21.0
24.C
a"" :
< ;
9:
'g;
c
u
\ fe
\ "
\ 5
\
\
lECEND
a =CL-I2
0 = GL - '4
« = CL - 16
H]
a"
Q.O.
UCENO
= a-i2
= CL - M
« = GL-1b
• • CL -16
3.0
6.0 9.0 12.0 Ib.O 18.0
VOLUME (liters)
0.0 3.0
6.0 9.0 12.0 15.0
VOLUME (liters)
LEGEND
=GL-12
= CL-U
=GL-I5
=GL-16
0.0 3.0 6.0 9.0 12.0 15.0 18.0 21.0 24 .C
VOLUME (liters)
0.0 3.0 6.0 9.0 12.0 15.0 IB.O 21.0 24.C
VOLUME (liters)
Fig. C-l. (cont)
73
-------
E
a
O
LEGEND
o-GL-12
o = CL-14
. . CL-15
. -GL-I6
'-GL-17
6.0 9.0 12.0 15.0
VOLUME (liters)
18.0
21.0
24.C
LEGEND
o = GL-I2
o -CL-14
« = CL-15
» = GL -16
9.0 12.0 15.0
VOLUME (liters)
21.0
LEGEND
"-CI.-I2
o-CL-14
.-GL-15
. -GL-16
• -GL-17
CD o-
a —:
9.0 12.0 15.0
VOLUME (liters)
18.0
21.0
LEGEND
o -CL-12
o -CL-14
' -GL-15
• . GL-16
• -CL-I7
0.0
9.0 12.0 15.0
VOLUME (liters)
LEGEND
o - GL -12
o = CL - U
• » CL-15
• • GL-16
• -GL-17
6.0 9.0 12.0 15.0
VOLUME (liters)
LEGEND
o = CL-12
o -CL-I4
• • CL-15
. -GL-16
•=CL-17
9.0 12.0 15.0
VOLUME (liters)
2<.C
Fig. C-l. (cont)
74
-------
L.ECEND
o-CL-12
o=GL-M
• -GL-I5
• -GL-I6
• . GL-17
LEGEND
o.CL-12
o-GL-14
• -GL-15
•-CI-16
« . Cl-17
3.0
9.0 12.0 15.0
VOLUME (liters)
6.0
9.0 12.0 15.0
VOLUME (liters)
18.0
9.0 12.0 15.0
VOLUME (liters)
LEGEND
a-CL-12
• -GL-15
• -Gl-16
'-GL-I7
.S:>
a.
LEGEND
o • CL -12
o-GL-U
• -GL-15
. -GL-16
..GL-17
^
I'l.
60
9.0 12.0 15.0
VOLUME (liters)
2VO
LEGEND
o-a-12
o oCL-M
• -GI-I5
' -GL-I6
• -CL-I7
9.0 12.0 15.0
VOLUME (liters)
9.0 12.0 15.0
VOLUME (liters)
Fig. C-l. (cont)
75
-------
APPENDIX D
COLUMN LEACHING STUDIES OF LIME/REFUSE MIXTURES
TABLE D-I
EXPERIMENT IDENTIFICATION FOR CODISPOSAL
OF LIME AND COAL WASTES
Weight of
Experiment No. Waste (g)
Amount of
Lime Added (%)a
CTWT-11-1
CTWT-11-2
CTWT-11-3
CTWT-11-4
CTWT-11-5
500
500
500
500
500
0 (control)
0.5
1.5
3
10
'Percentage based on waste. Lime added as slurry, then mixed and
dried. Mixtures leached with upward distilled water.
TABLE D-II
ANALYSES FOR DYNAMIC LEACHING STUDIES OF
LIME/REFUSE MIXTURES
Experiment No. CTWT-11-1
(Control)
Sample No.0
12
16
18
'Concentrations in us/mi unless noted otherwise.
"Water flow was stopped at this point, air was passed through the column for 2 wk, then water flow was resumed.
20
Vol(Jl)
pH
TDS(%)
F*
Na
Al
K
Ca
Cr (ng/t)
Mn
Fe
Co
Ni
Cu
Zn
Cd (jtg/£)
0.043
1.8
6.54
12
12
1200
4.6
380
610
34
13200
20
30
4
48
230
0.172
1.9
6.19
11
8.6
1100
2.4
370
560
33
12000
18
28
4
48
250
0.344
1.9
4.06
6.5 •
5.6
720
1.3
330
450
22
7790
12
18
3
29
170
1.026
2.4
0.56
1.8
1.1
74
1.1
100
90
3
1100
2
3
0.34
4
25
1.927
2.6
0.13
1.2
0.5
13
1.2
30
11
0.7
230
0.4
0.6
<0.02
0.9
4.6
3.581"
3.3
0.05
1.3
0.6
3
2.2
12
3
0.2
100
0.1
0.2
<0.02
0.3
1.4
3.963
2.2
0.34
0.7
3.6
42
5.2
60
30
1
700
0.7
0.8
0.5
1
7
4.206
2.4
0.18
0.7
2.1
21
3.5
31
7
0.5
380
0.3
0.4
0.20
0.7
2.5
76
-------
TABLE D-III
ANALYSES FOR DYNAMIC LEACHING STUDIES OF
LIME/REFUSE MIXTURES
Experiment No. CTWT-ll-2
(0.5 wt% Lime)
Sample No.*
12
16
18
20
Vol(/)
PH
TDS(%)
F
Na
Al
K
Ca
Cr (n%lt)
Mn
Fe
Co
Ni
Cu
Zn
Cd (tig/I)
0.055
2.1
5.40
9
4.0
790
1.4
450
480
33
10750
18
28
4
50
240
0.198
2.2
4.33
9
3.1
610
3.3
510
370
26
8300
14
21
3
35
200
0.396
2.3
2.89
5.6
1.9
420
0.4
490
280
18
5670
10
15
2
23
140
1.166
2.6
0.58
1.1
0.7
54
0.4
380
60
3
950
1.5
3
0.2
4
30
2.065
2.9
0.19
0.5
0.5
10
1.1
240
5
0.6
260
0.3
0.5
<0.02
0.9
5
4.237"
3.5
0.04
<0.2
0.4
0.8
1.1
60
2
0.2
75
<0.07
0.2
<0.02
0.3
1
4.658
2.2
0.55
1.2
2.3
47
2.6
250
50
2
1020
0.8
1
0.9
2
9
4.946
2.6
0.14
0.5
0.8
8
1.0
70
4
0.3
205
0.1
0.2
0.1
0.4
3
"\\'n(er flow
ons in jjjj/rn£ unless noted otherwise.
wn> slopped at this point, air was passed through the column for _ wk. then wnier llnw \v;i> resumed.
TABLE D-IV
ANALYSES FOR DYNAMIC LEACHING STUDIES OF
LIME/REFUSE MIXTURES
Experiment No. CTWT-11-3
(1.5 wt% Lime)
Sample No.*
12
16
18
20
VolU)
PH
TDS(%)
F
Na
Al
K
Ca
Cr (tig/t)
Mn
Fe
Co
Ni
Cu
Zn
Cdfog/l)
0.048
2.6
1.72
5.9
7.6
380
1.3
510
140
21
2820
13
18
2
24
130
0.190
2.6
1.54
5.0
4.9
320
3.7
530
120
17
2330
11
15
1
20
110
0.332
2.7
1.19"
3.7
4.7
240
0.9
550
80
13
3720
8
11
1
16
90
1.064
3.0
0.49
1.6
1.3
55
0.6
500
8
4
540
2
3
0.2
4
30
1.944
3.2
0.29
0.6
1.1
24
1.0
400
<1
2
260
0.8
2
<0.02
2
20
3.759"
3.9
0.13
0.3
0.8
6
0.8
220
<1
0.4
105
0.1
0.4
<0.02
0.6
3
4.104
2.3
1.02
1.8
1.3
110
0.2
300
100
3
1980
1
3
2
6
45
4.387
2.6
0.37
0.6
0.5
34
0.2
170
30
1
710
0.4
0.9
0.35
2
4
irnitiins in uglml unless noted otherwise.
lnw wns stopped at this point, air was passed through the column lor - wk. iht-n w;iti*r t1<«w w;i* rt-
77
-------
TABLE D-V
ANALYSES FOR DYNAMIC LEACHING STUDIES OF
LIME/REFUSE MIXTURES
Experiment CTWT-11-4
(3 wt% Lime)
Sample No.*
12
16
18
•('nncemr.i'inns in mlmt unless noted oiherwise.
"Water llnw wa» stopped at this point, air was passed through ihe column lor 2 t
20
VolU)
pH
TDS(%)
F
Na
Al
K
Ca
Cr (M§//)
Mn
Fe
Co
Ni
Cu
Zn
Cd(Mgfl)
0.042
6.6
0.54
0.15
7.9
0.7
8.9
890
<1
3
120
0.7
1
0.04
0.5
5.4
0.168
6.3
0.48
0.15
6.4
<0.6
12.4
870
<1
2
120
0.6
0.9
0.04
0.4
4.0
0.336
6.5
0.37
<0.15
3.4
<0.6
6.1
780
23
2
69
0.4
0.7
0.04
0.2
2.0
1.125
6.8
0.27
<0.15
1.5
<0.6
5.3
700
3
1
14
0.2
0.3
0.03
0.1
0.6
2.076
7.4
0.24
<0.15
1.1
<0.6
3.5
620
2
0.6
7
0.2
0.2
0.02
0.08
0.4
4.2.W
7.9
0.15
<0.15
1.0
<0.6
3.0
380
<1
0.3
3
<0.07
0.1
0.02
0.07
0.6
4.562
2.8
0.73
4.8
4.9
180
7.9
550
19
12
700
8
12
0.9
14
100
4.830
3.0
0.45
1.6
2.0
54
8.2
540
6
5
300
3
4
0.2
5
32
n.s resumed.
TABLE D-VI
ANALYSES FOR DYNAMIC LEACHING STUDIES OF
LIME/REFUSE MIXTURES
Experiment CTWT-11-5
(10 wt7t Lime)
Sample No.*
12
16
18
20
Vol(/)
pH
TDS(%)
F
Na
Al
K
Ca
Ci(ns/l)
Mn
Fe
Co
Ni
Cu
Zn
Cd (MB//)
0.044
13.1
0.50
0.18
6.3
<0.5
3.8
1100
<1
<0.02
<0.1
0.05
0.1
0.03
0.02
<1
0.174
13.2
0.51
0.28
2.9
<0.5
1.8
1400
<1
<0.02
<0.1
0.05
0.1
0.04
0.03
<1
0.304
13.1
0.46
0.20
0.9
<0.5
1.7
1100
<1
<0.02
<0.1
0.1
0.1
0.02
0.02
<1
1.045
12.9
0.47
0.25
0.6
<0.5
1.2
1100
<1
<0.02
<0.1
0.1
0.06
0.02
0.02
<1
1.910
12.9
0.49
0.25
0.6
<0.5
1.7
1200
<1
<0.02
<0.1
0.05
0.08
0.03
0.03
<1
4.002"
12.6
0.28
0.12
1.6
<0.5
1.0
380
<1
<0.02
<0.1
<0.05
<0.03
<0.02
0.01
<1
4.297
10.7
0.36
<0.1
16
<0.5
3.3
920
<1
<0.02
<0.1
<0.05
0.05
0.03
0.02
2
4.563
11.4
0.15
<0.1
1.3
0.5
0.9
360
<1
<0.02
<0.1
<0.05
<0.03
<0.02
<0.01
<1
•('I>MIciiJr.iii"M- in M/mt unless mned otherwise.
*\V;iicr lluw wn> slopped HI this point, air wn> pas>ed ihrmixh ihe t
iliinui in
»k. ilu
rotiined.
78
-------
I-
USBfl
o - CTWTtM
o - CTWtn-2
• - CTWTn-j
• - CTWTn-4
» . CTWTff-5
20 iO 40 SO
VOLLfcC (Liters)
6O 70 80
o . cTwrn-1
o . CTWTII-2
«-C7wtn-i
• - CTWTn-4
» - CTWTn-5
00 K>
2O JO 40 SO 60
VCLUiC (Liters)
70 80
LECOC
o . CTWTn-l
o . cTwrn-2
• . CTWTn-3
• • cTwrn-4
• . CTWTII-5
00 10
20 JO 40 50 60
VOLLKE (Uters)
80
8
\sssm
o . CTWTD-I
o . CTWTtl-2
» • CTWTII-3
« - CTWTtl-4
• • CTWTH-5
00 K) 20
JO 40 SO
VOLUKC (Liters)
60 70 80
\££BSt
a ' CTWTn-l
o . CTWTII-2
• - CTWTH-3
• - CTWTn-4
» = CTWTn-s
20 JO 4O SO
VOLLKC (Liters)
60 70 80
I
5
"o-
a . CTWTn-l
o . CTWTH-2
• - CTWTn-3
• - CTWTtt-4
» - CTWTn-b
20 JO 4O SO
VOLUvE (Liters)
60 70 80
Fig. D-l.
The pH and trace element concentrations for dynamic leaching experiments with lime/refuse
mixtures.
79
-------
P:
CTWTn-1
a - CTWTD-2
4 - CTWTIt-3
• - CTWT11-4
» - CTWTD-5
OOW 20JO*Oi06070
vai>€ (Liters)
00 ,»
ty.
ttstc
o . CTWTH-I
o - CTWT11-2
• - CTWT11-3
• - CTWTtl-4
» . CTWTI1-5
20 30 40 SO"
vOLU»e (Liters)
60 70 80
00 X)
2O JO «O SO
VOLUKC (Liters)
60 7O BO
LEfiQfi
o - CT»fTn-1
o-CTWTH-2
» - CTWln-3
• - CTWTH-4
« - CTWTH-5
K) JO JO 4O SO 6O
(Liters)
p-
00
20
\
b!
$
. CTWTH-1
CTWln-2
• - CTWT1I-4
» » CTWTII-i
JO 40 SO
VOLL*£ (Liters)
60 70 80
a -CTWTI1-I
o . CTWTI1-2
• . CTWTI1-3
« - CTWTII-4
• - CTWTII-5
OOI020J040S0607080
Fig. D-l. (cont)
80
-------
\sssm
a . ciwrn-i
o . crwrn-2
•. crwrn-3
• • cTwin-«
»« CTwin-s
0010?OJO*OS0607080
VCXUkC (Utes)
OOI020M40M6070
Fig. D-l. (cont)
81
-------
APPENDIX E
PROGRAM CODE FOR DETERMINING THE COST OF ALKALINE
NEUTRALIZATION OF COAL WASTE DRAINAGES
LASL Identification No. 1065.
PRDGRRM L RHDF IL (I NPUT. OUTPUT. TRPE5= I NPIJT. TRPE6=OUTPUT^
DIMENSION PPMFE(20> .PDLIME<20> . TPYLIME<20> > TPDLIME (20'.' .
1TPDTDS <20> ,PPILIME<6> . COSTLIM (20. 6) «TTPD<20> . CLRCOST <20::' •
2DPCOST(20^.CHPCOST<20>.CLRRR<20>
C ;ET FLRG TD 1 FDR SIN'3LE IRON CDNC. FERDIN. ELSE 0
IF'HFLRG.GT.O '50 TO 10
DnTR PPMFE'10..20..50..100..200..400..500..600..700..
1900..1000..1100.«130G.»1500.«1700..1900.»2000.<2500.«3000.»3500.,
GD TO 101
10 RERIK5»991>PPMFE<'O
101 RERD<5.. 992 '30 TO 12
11 DD 15 1=1.20
12 PDLIME(O=1.2406E-04»PPMFE(I>
TPYLIME(I>=PDLIME=TPYLIME(D.'365.
13 DO 14 J=l,6
PPILIME(.J>=36.*3*J
14 COSTLIM(I,J>=PRILIME(J>»TPYLIME(I>
C»»»» PRILIME !S PRICE OF LIME DELIVERED IN $'TON!COSTLIM IS RNNURL
C COST OF LIME
TPDTDS(I>=-3.»PPMFE(I>»CUFT*62.4x730.E09
C»»»» TONS PER DRY OF TOTRL DISSOLVED SOLIDS
TTPD < I> =TPDTDS (I> -t-TPDLIME SCLfiRR (I> =1 30. »TTPD (I>
IF(CLRRfta>.LT.100.> CLRRR=100.
IF(CLRRR.GT.1000.> GO TO 21
CLRRBS=10000.-6.67*(1000.-CLfiRRa»
'3D TO 22
21 CLRRB3= 10000.+7. »-1000.')
22 flDJCBS=CLRRBS»(235.x39.>
235 IS MRR 1973 CHE COST INDEX - CRN BE CHRNGED FOR LRTER USE
VflR SLURRY IS GPM BOTTOM FLOU FROM SETTLER
SLURRY=1.70776E-06»CUFT
CH=250.»SLURRY
MRX TOTRL HERD OF 250 PS I HRS BEEN RSSUMED FOR COST CRLC
IF *3- 33*500.
250.6 IS MRR 73 COST INDEX FOR PUMPS
GO TO 302
301 PUMPCST=<250.6'115>»3.33*(500.-»-4.5*<:CH-400.>*».63>
302 IF(SLURRY.GT.7.67) GD TD 401
302 IS FDR 1.5 IN PIPE?401-2"»402-2.5"!403-3-?404-4";405-5"
RSSUME 1500 FT TOTRL LENGTH OF PIPE
DUM=1500»(264x115)
PIPECST=2.2»DUM
GD TD 409
401 IF(SLURRY.GT.12.34> GD TO 402
PIPECST=2.75*DUM
GO TD 409
402 IF(SLURRY.GT.17.97> GD TD 403
PIPECST=3.3»DUM
82
-------
GO TO 409
403 IF GO TD 404
PIPECST=4.2»DUM
GO TD 409
404 IFCSUJRRY.GT.4iS.> GO TD 405
PIPECST=5.2*DUN
GD TD 409
405 PIPECST=6.3*DUri
MRITE<6'993'» '
409 PPCOST=PUMPCST+PIPECST
DT 1 =2 . 36*RD JCBS1I>T2= 1 . 43»DT 1 $DT3= 1 . 35»DT2
CLRCOST C I > =PPCOST+DT3
HPPUMP=500. » 1'SLUP.RY '3960. > »1 . 33*HPCLfl=CLflPfi ». 01 5
EKI,JH=0.7457»
DPCDST =365. »40. +ELECDST
CflPCQST < I > = . S533*CLflCDST < O
IF(NFLftG.GT.O> GD TD 600
15 CONTINUE
i.JRITE<6»994->RflIN.flCRES.FRflflB
i.JRITE<6.995>
DD 500 1=1.20
URITE<6.996)PPMFE »CLflRfl »CflPCDST(I> .DPCDST(D
500 CONTINUE
MRITE<6»997> » J=l »6>
URITE <6- 993) < » J=l »6) « 1=1 »20>
GD TD 399
600 CONTINUE
URITE <6»994)RHIN»ftCREStFRflftB
IJRITE<6»995>
MR I TE <6 • 996) PPMFE <1 > F TPDL I ME <1> > CLRRfl <1 > • CRPCOST <1 > • DPCDST < 1>
350 CONTINUE
URITE<6.897>
URITE (6.997) J) » J=l .6> » 1 = 1 » 1)
399 REftD(5'990)NEXIT
IF(NEXIT.GT.O) GD TD 5
900 CONTINUE
990 FORMftTCIl)
991 FDRMftT(FlO.O)
992 FDRMflT<3x,*. FRftCTIDN RBSORBED: «-,2X»F5.-4'>
995 FDRMRTdHO^PPM IRDN».Tl 1 »»TDNS LIMExDfiY»»T26«»CLftRIFIER flRER*.
1T42.»RNN. CflP. CDiT»«T53.»flNN. DPER. COST*)
996 FDRMRT<3X»F6.0.T11.F3.4.T26»F10.2»T42»F10.2»T53»F10.2)
397 FORflRT(lHO.»LIME COST flT VRRIDUS PRICESt SflME PPMS FE RS RBDVE*)
993 FDRriflT<» ».6F10.2)
997 FDRMflT
-------
REFERENCES
1. E. M. Wewerka, J. M Williams, P. L. Wanek, and J. D. Olsen, "Environmental Contamina-
tion From Trace Elements in Coal Preparation Wastes: A Review and Assessment of the
Literature," Los Alamos Scientific Laboratory report LA-6600-MS (August 1976).
2. R. A. Meyers, Coal Desulfurization (Marcel Dekker Inc., New York, 1977).
3. E. M. Wewerka, J. M. Williams, N. E. Vanderborgh, A. W. Harmon, P. Wagner, P. L.
Wanek, and J. D. Olsen, "Trace Element Characterization of Coal Wastes — Second Annual
Progress Report, October 1, 1976-September 30, 1977," Los Alamos Scientific Laboratory
report LA-7360-PR (also EPA-600/7-78-028a) (July 1978).
4. E. M. Wewerka and J. M. Williams, "Trace Element Characterization of Coal Wastes, July
1, 1975-June 30, 1976," Los Alamos Scientific Laboratory report LA-6835-PR (March 1978).
5. E. M. Wewerka, J. M. Williams, and P. Wagner, "The Use of Multimedia Environmental
Goals to Evaluate Potentially Hazardous Trace Elements in the Drainage From High-Sulfur
Coal Preparation Wastes," in preparation.
6. National Academy of Sciences/National Academy of Engineers Committee, Underground
Disposal of Coal Mine Wastes (Washington: National Academy of Sciences, 1975) pp. 78-
79.
7. Annon., Chemical Ki^inemii-,'. 85, No. 12:7 (May 22, 1978).
8. F. C. Jelen, Cost and Optimization Engineering (McGraw-Hill Book Co., New York, 1970),
p. 440.
9. Annon. "Key Chemical Lime," Chemical £ Engineering News, p. 10 (April 24, 1978).
10. Ackenheil & Associates Geo. Systems, Inc., "Evaluation of Pollution Abatement Techniques
Applicable to Lost Creek and Brown's Creek Watershed, West Virginia," Appalachian
Regional Commission report NTIS PB-242 722 (October 1973).
11. R. H. Perry, etal., Eds., Chemical Engineer's Handbook, 4th ed. (McGraw-Hill Book Co.,
New York, 1963).
12. R. S. Aries, et al., Chemical Engineering Cost Estimation (McGraw-Hill Book Co., New
York, 1955).
13. P. M. Kohn, "CE Cost Indexes Maintain 13-Year Ascent," Chemical Engineering, 85, No. 11,
pp. 189-190 (May 8, 1978).
14. J. S. Scott, and K. Bragg, Eds., "Mine and Mill Wastewater Treatment," Environmental
Protection Service (Canada) report EPS3-WP-75-5 (December 1975).
15. H. W. Cremer and T. Davies, Eds., Chemical Engineering Practice, Vol. :t. Solid Systems
(Academic Press Inc., New York, 1957), pp. 259-283.
84
-------
16. H. Popper, Ed., Modern Cost-Engineering Techniques (McGraw-Hill Book Co., New
York, 1970). (Note: p. vi is essential for indexing costs.)
17. J. P. Capp and L. M. Adams, "Reclamation of Coal Mine Wastes and Strip Spoil With Fly
Ash," Amer. Chem. Soc., Div. Fuel Chem. Preprints 15(2) (1971).
85
-------
TECHNICAL REPORT DATA
fPleost read tmuructiont on the revene before completing)
1. REPORT NO.
EPA-600/7-79-144
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
Trace Element Characterization of Coal Wastes: Third
Annual Progress Report
E. REPORT DATE
June 1979
6. PERFORMING ORGANIZATION CODE
AUTHORS E.M.Wewerka, J.M.Williams, L.E.Wangen,
J.P.Bertino, P.L.Wanek, J.D.Olsen, E.F.Thode,
and P. Wagner
I. PERFORMING ORGANIZATION REPORT NO.
LA-7831-PR
9. PERFORMING OROANIZATION NAME AND ADDRESS
Los Alamos Scientific Laboratory
University of California
Los Alamos, New Mexico 87545
10. PROGRAM ELEMENT NO.
INE825
11. CONTRACT/GRANT NO.
EPA Interagency Agreement
IAG-D5-E681
1J. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development (*)
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Annual: 10/77 - 9A8
14. SPONSORING AGENCY CODE
EPA/600/13
is. SUPPLEMENTARY NOTES Cogp0nsored by j^g Project off leers ~. D. A.Kirchgessner (EPA)
and C. Grua (DoE). EPA-600/7-78-028 and -028a are earlier progress reports.
16. ABSTRACT
The report gives third year results of a program to characterize the
trace element content of coal waste. In 1978 laboratory experiments were performed
to investigate the efficacy of several control options to treat coal wastes at the pre-
paration plant or during disposal. The research revealed that calcining Is one of the
more effective and permanent means of treating high sulfur coal wastes before dis-
posal to decrease, quite dramatically, the release of environmentally undesirable
pollutants into the drainages from disposal sites. Co-disposal of the coal wastes with
lime or limestone to neutralize the acid drainage and contain soluble aqueous contam-
inants within the waste site is also a promising control. Other experiments examined
the feasibility of using natural sealants (e.g. , clays, soils, calcite, and cements) to
isolate the disposal site from its immediate environment. The report discusses the
various trade offs for these control options in terms of contaminant reduction, com-
plexity, permanency, and cost. An assessment of coal preparation wastes from the
Appalachian region has begun: work on refuse from a single plant indicates signifi-
cant acid drainage, even with coal wastes with a low percentage (< 1%) of pyrite.
Experiments show that Al, Mn, Fe, Ni, and Cu ions are potentially of concern, as
their concentrations exceed certain Multimedia Environmental Goal (MEG) values.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COSATi Field/Group
Pollution
Coal
Waste Treatment
Roasting
Chemical Analysis
Sulfur
Drainage
Calcium Oxides
Calcium Carbonates
Sealers
Pollution Control
Stationary Sources
Coal Waste
Trace Elements
Acid Drainage
13B
08G
13H
07D
07B
11A
8. DISTRIBUTION STATEMENT
Release to Public
IS. SECURITY CL
Unclassified
31. NO. OF PAGES
94
30. SECURITY CLAS
Unclassified
EPA Form 1220-1 (I-T1)
86
-------