EF&-9O8/4-78-OQ3
TRACE ELEMENTS ASSOCIATED
WITH OIL SHALE
AND ITS PROCESSING
United States
Environmental Protection
Agency Region 8
Denver, Colorado 8O295
MAY 1977
-------
TRACE ELEMENTS
ASSOCIATED WITH OIL SHALE
AND ITS PROCESSING
Prepared For
Industrial Environmental Research Laboratory
(Cincinnati)
Environmental Protection Agency
Cincinnati, Ohio 45268
Under Contract No. 68-02-1881
May 1977
TRW I
ENVIRONMENTAL
ENGINEERING
DIVISION
' ' « .1 ,
Denver Research Institute
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ABSTRACT
This report includes a summary of existing trace
element composition data for shale and its products, an
evaluation of these data and related studies to estimate
the distribution of trace elements among shale products
during oil shale processing, and predictions of the dis-
position and ultimate fate of trace elements after waste
disposal or product use. Wide ranges in trace, element
concentration reflect natural grographic and vertifical
profile variations in shale.
This report has been reviewed by EPA Region VIII
and approved for publication. Approval does not signify
that the contents necessarily reflect the views and polcies
of the Environmental Protection Agency, nor does mention
of trade names or commercial products constitute endorsement
or recommendation for use.
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TABLE OF CONTENTS
1.0 INTRODUCTION AND SUMMARY 1
2.0 THE ELEMENTAL COMPOSITION OF OIL SHALE AND ITS PRODUCTS .... 4
2.1 Kerogen 4
2.2 Major Inorganic Components of Green River Shale 4
2.3 Trace Elements in Oil Shale 5
2.4 Levels of Trace Elements in Processed Oil Shale 17
2.5 .Levels of Trace Elements in Shale Oils 17
2.6 Trace Elements in Retort Gases 22
2.7 Trace Element Composition of Retort Water 25
3.0 TRACE ELEMENT MASS BALANCES AROUND OIL SHALE RETORTS 25
3.1 Arsenic 26
3.2 Mercury 30
3.3 Zinc, Lead, and Copper Balances 30
3.4 Cadmium, Selenium, and Antimony Balances 30
3.5 Other Elements (Be,Mo,Co,Ni,Cr,Zr,V,Mn and F) 31
4.0 THE DISPOSITION AND ULTIMATE FATE OF TRACE ELEMENTS
CONTAINED IN OIL SHALE PRODUCTS AND PROCESSING WASTES 32
4.1 Retort Gases 32
4.2 Retort Water 33
4.3 Retorted Shale 34
4.3.1 Fugitive Dust 34
4.3.2 The Water Solubility of Minor Elements in
Retorted Shale 35
4.3.3 The Effects of Using Process Water to
Moisturize Retorted Shale 39
4.3.4 The Accumulation of Trace Elements by
Vegetation Growing on Retorted Shale 42
4.4 Crude Shale Oil 44
4.4.1 Combustion 44
4.4.2 Upgrading and Refining 46
n
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TRACE ELEMENTS ASSOCIATED WITH OIL SHALE AMD ITS PROCESSING
1.0 INTRODUCTION AND SUMMARY
All fossil fuels contain minor elements which may potentially be
mobilized during extraction, processing, and end use. Certain coals and
petroleum oils for instance are known to contain relatively large amounts
of cadmium, boron, selenium or vanadium. Such elements may be released
to the environment as processing wastes or combustion emissions and can have
toxic effects on plants, animals, and man. The processing of fossil fuels
may also involve the use of Catalysts and other chemicals which contain large
amounts of metalic elements (e.g., Co, Ni or Mo in petroleum refining
catalysts).
Because of the potential substitution of oil shale products for coal
and petroleum products, and because of the large volumes of oil shale which
would have to be extracted and/or processed in order to provide such sub-
stitutes, concern has developed regarding the mobilization and fate of trace
elements contained in oil shale. This concern has resulted in the generation
of a body of data regarding the composition of raw oil shale, oil shale pro-
ducts, and processing wastes. Studies have also been conducted to determine
the potential for release of trace elements to the air, water, and biological
environments.
This report includes a summary of existing trace element composition data
for shale and its products, an evaluation of these data and related studies to
estimate the distribution of trace elements among shale products during oil
shale processing, and predictions of the disposition and ultimate fate of
trace elements after waste disposal or product use. Although SOIMG uncertain-
ties and data gaps exist at present, a number of general conclusions have been
deduced from the available trace element data and studies.
For many elements, wide ranges of concentrations have been
reported for oil shale and its products. These ranges reflect
natural geographic and verticle profile variations in the shale,
differences in retorting methods, and uncertainties associated
with various sampling and analytical techniques.
-------
Compared to average rocks, oil shale contains much higher
levels of Se and As, moderately higher levels of Mo, Hg, Sb,
and B and lower levels of Co, Ni, Cr, Zr and Mn.
Other elements are present in concentrations typical of
common rocks. .
Most elements are not converted to volatile or oil soluble
substances during retorting and are consequently retained by
processed shale. However, up to 30% of Hg, 15% of As, and 8%
of Se in raw shale can be found in shale oil, retort gases and
retort waters.
Shale oils contain trace elements derrived from raw shale in
both soluble and partiaulate form. The concentrations of most
trace elements in shale oil are similar to or less than those
found in many petroleum oils. Arsenic is a notable exception,
with levels in shale oil up to 50 ppm compared to a maximum of
about 4 ppm for residual fuel oil.
Retort gases contain very small amounts of metallic and heavy
elements. Particulate and H2S control equipment will likely
collect most nf tha trace elements before release to the
atmosphere.
Levels of most trace elements in retort waters are in the parts
per billion range. Many treated municipal and industrial waste-
waters contain higher levels of transition and heavy metals than do
retort waters. Arsenic, boron, and floride may present problems
for direct discharge to surface waters or for irrigation use.
Most metals contained in retorted shale are not readily water
soluble. However, elements which form anionic species (B, F,
Mo, Se) can be leached from retorted shales by percolating
water. Properly compacted processed shale has a low perme-
ability, and only small amounts of leachate are expected under
field conditions in the Piceance and Uinta Basins.
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The effects of using retort water and/or process wastewater
for moisturizing retorted shale are not well known. The available
data suggest that the additional amounts of soluble trace elements
added to retorted shale in wastewaters are small. Further, the
alkaline and absorbtive properties of retorted shale are expected
to immobilize most metallic elements.
Vegetation growing on retorted shale may accumulate toxic levels
of boron. Molybdenum may accumulate in some plant species to
levels toxic to grazing animals.
Measurements during combustion tests in a utility boiler suggest
that large fractions of several elements in crude shale oil are
unaccounted for in flue gas particulate matter. Elements such
as Hg, Se, and As may exit the stack in gaseous form. Less volatile
elements are likely retained in ash or deposits within the boiler
system.
During upgrading and refining of crude shale oil, metallic elements
tend to concentrate in higher boiling fractions and in shale coke.
Volatile elements (e.g., As and Se) found in lower boiling dis-
tillates would be removed prior to or during catalytic hydrogenation.
Spent catalyst media containing Ni, Co, Mo and shale derv/ed
arsenic and other trace elements would be either disposed with
retorted shale or shipped for reprocessing.
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2.0 THE ELEMENTAL COMPOSITION OF OIL SHALE AND ITS PRODUCTS
Oil shale is generally defined as organic rich sedimentary rock which
yields substantial quantities of liquid hydrocarbons when subjected to des-
tructive distillation. Oil shales of the Green River formation of Colorado,
Utah, and Wyoming are actually dolomitic marlstones rather than true "shales"
since they contain Tittle or no clay. Like true shales, however, oil shales
have a laminated structure and natural cleavage planes.
2.1 KEROGEN
The organic component of oil shale ranges from 5 to 30% by weight and
consists mostly of kerogen, a heteroatomic, wax-like polymer which is insoluble
in organic solvents. Around 10% of the organic material is bitumen (also
a polymer, but soluble in organic solvents). Cross-linking of the polymer
units within the shale matrix is extensive and accounts for the cohesive
nature of rich shales. Oxygen, sulfur, and nitrogen occur primarily as
heterocyclic and polymeric cross-linking components of the kerogen molecule.
Table 1 presents the major element composition of organic material, in oil
shale.
2.2 . MAJOR INORGANIC COMPONENTS OF GREEN RIVER SHALE
The inorganic fraction of Mahogany oil shale consists mainly of silicon,
calcium and magnesium, with smaller amounts of iron, aluminum, sodium and
potassium. Table 1 presents selected composition data for the inorganic frac-
tion of oil shales. Elements are commonly reported as oxides with no
implication as to mineralological form.
Table 2 summarizes the results of several mineralogical studies of oil
shales. The inorganic fraction of raw oil shales consists mainly of quartz,
dolomite, calcite, albite, and potassium feldspar. Dawsonite, nathcolite,
analcine, and siderite are also present in some shale samples. Generally,
the silicate minerals (quartz, felspar, albite) tend to be associated with
the organic layers in laminated oil shales; dolomite and calcite are dominant
in the inorganic layers.
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2.3 TRACE ELEMENTS IN OIL SHALE
In recent years, considerable data on the minor element composition of
oil shales have accumulated. Figures 1, 2, and 3 show the ranges of values
reported by the U.S.6.S., the LERC, and the lessees of Tracts C-a and C-b
for selected trace element of particular environmental interest. For many
of the selected elements, reported levels vary by one order of magnitude and
for a few elements, two orders of magnitude. The ranges reflect at least
three factors; 1) natural variations in oil shale samples in a vertical pro-
file depending en mineral and organic matter composition, 2) natural geographic
variations, and 3) variations in measurements due to different sampling, pre-
paration, and analytical techniques. In most cases, it is difficult to dis-
tinguish the relative importance of these three factors. For example,
variations between laboratories for shale from the same area are often
as great as variations geographically as determined by the same laboratory. In
addition, values for some elements are consistently higher (e.g., Mi and Cr) or
lower (e.g., Pb) according to LERC data than according to U.S.G.S. data
(Figures 1 & 2). One possible explanation for anomalously high Ni and Cr
levels is sample contamination from stainless steels during crushing and
screening.
Where similar sample preparation and analytical techniques have been
employed, some geographic and vertical distribution trends have been preliminarily
identified. For instance, shale from Tract C-a appears to be generally higher
in Cd and lower in Se, As, and F than shale from Tract C-b (Figure 3). In con-
trast, the U.S.G.S. data for Mahogany Zone shales from the Piceance and Uinta
Basin do not indicate significant geographic differences in levels of most
elements. LERC data suggest that typical levels of Cd and Sb may be higher,
and levels of Ni and Cr lower in the saline zone oil shale of the northern
Piceance Basin than in Mahogany Zone shale (Table 3-a).
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Table 1. Major Element Composition of Raw Green River Oil Shales
Mahogany Zone in Colorado
ORGANIC FRACTION (-14%)
C
H
N
S (organic)**
0
INORGANIC FRACTION (-86%)
Si02
CaO
A1203
MgO
Fe203
Na20:.
K20
p2°5
S03**( inorganic)
Mineral C02
TOTAL
(D*
-
-
-
-
Ash
27.8
15.1
8.6
6.5
3.0
2.0
1.5
-
1.8
19.9
86.2
(2)
Percent
_
-
-
-
-
(3)
Mahogany
Utah
(4)
R4 Zone
Colorado
i
(5) ;
of Total Organic Material
80.5
10.3
2.4
1.04
5.8
100
Composition (Percent
26 26 - 40
17.5 8.3 - 17.5
6.5
5.3
2.6
2.6
1.0
0.9
0.5-4.4
-
-
6.3 - 9.4
4.5- 5.6
2.6 - 4.3
1.8 - 2.7
1.0 - 3.4
-
0.1 - 1.2
9.9 - 25.7
80.4
80.7
10.4
2.56
1.0
5.33
100
of Raw Shale
30.1
15.4
6.7
7.0
-
1.5
1.8
-
1.5
22.4
86.4
_
:
-
-
Basis)
27 - 41
3 - 7.5
7-10
1 - 2.7
3-4
1 - 2.5
1.3 - 2.6
2 - 0.6
3.4 - 6
-
-
*See References at end of text.
**Sulfur in shale is approximately 33% organically bound and 67% inorganically combined; the latter
mainly as Pyrite and Marcasite (Fe$2).
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Table 2. Major Mineral Components of Green River Oil Shales
Mineral
Dolomite
Calcite
Albite
11 lite
Quartz
Analcite
Feldspar
Chemical
Formula
CaMg (C03)2
CaCOa
NaAlSi308
Mahogany Zone
Order of !
Abundance* 1
. (2)**(5) '
1 1
4 2
3 5
KAl2(AlSi3)08(OH)2 N/A 6
Si02 2 4
NaAlSi206 H20 5 3
KAlSi3Q8 N/A 7
Pyrite FeS2 7 8
Nahcolite NaHCOs
N/A N/A
Dawsonite NaAl(OH)2C03 6 N/A
Wt % Raw Shale
(3) (6) (4) (7)
33 4Q 32 32
20 16 14
12 N/A 10 10
11 13 19 12
10 13 15 13
74 IN/A
4 21 66
2 1 N/A 1
00 IN/A
j 0 0 N/A N/A
R4 Zone R5 & R4 Zones
Order of
Abundance*
(2)
2
3
4
N/A
1
3
5
8
6
7
Wt % Raw Shale
, (8) (9)
20 24
N/A
10 10
Trace N/A
20 15
N/A N/A
5 10
N/A N/A
N/A 17
12 9.5
1>2>3 etc,
**See references at end of text
N/A = not available
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Range of Concentrations (ppm)
H 1 1 1 H \
f- - I Hg
iSb
-*Se
I 9 | Mo
I ICo
i INI
i |Pb
I I As
oo i ICr
iCu
|Zr
1 B
Zn-H V
|Mn
I IF
1 1 1 1
0.01 0.05 0.1 0.5 1 5 10 50 100 500 1000 5000
Figure 1. Levels of Selected Elements in Raw Oil Shale - U.S. Geological Survey (2,10)
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Range of Concentrations (ppm)
I
-4Cd
-IHg
HBe
-|Sb
I ISe
I
Co
I 1 As
I IZr
I -
IN1
ICr
HZn
I IV
I IMn
^
4-
0.01 0.05 0.1
0.5 1
5 10
50 100
500 1000 5000
Figure 2. Levels of Selected Trace Elements in Raw Oil Shale - LERC (VI)
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Range of Concentrations (ppm)
--r-Hh
Cd
-H ISe
^+ , AS
-I
0.01
0.05 0.1
0.5 1
5 10
50 100
500 1000
Figure 3. Levels of Selected Trace Elements in Raw 011 Shale on Federal Lease Tracts C-a and C-b (12,13)
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Table 3-A . Mean Levels of Selected Trace Elements 1n Raw Oil Shale - Comparison of Reported
Data for Class I Elements* (ppm)
Be
Hg
Cd
Sb
Se
Mo
Co
N1
Pb
As
Cr
Cu
Zr
B
Zn
V
Mn
F
ment
U.S.G.S.
(1,10)
0.4
1.0
1.0
1.5
10
10
25
20
35
34
37
44
65
70
100
250
1000
LERC
(11)
Mahogany Saline
Zone Zone
2 1
0.5
0.1 0.4
0.4 3
3.0 1.5
15 30
9 4
300 85
3 15
3.0 20
400 100
45 30
30 50
80 50
15 30
100 80
250 250
2000 1000
Tract C-a
(12)
0.6
2.4
0.5
0.32
-
-
6.5
129
550
Tract C-b
(13)
0.22
.5
1.2
2.2
-
-
38
41
1300
Battelle
(14)
0.2
-
0.35
5
-
11
30
40
80
25
64
~
-
115
-
Berkeley
(15,16)
0.13
1.0
1.5
-
14
9
16
30
88
-
37
-
TRW
(17)
1
20
44
Representative
Mean Value
1.3
0.4
1
1
1.5
10
10
25
20
35
34
37
40
65
70
100
250
1000
*Class I Elements - Those which potentially pose environmental hazards and/or tend to be relatively
abundant in fossil fuels.
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Table 3-B. Summary of Analytical Techniques Used for Trace Elements in
Oil Shale
U.S.G.S.
Element (1,10)
Be
Hg Wet Ash, F. A. A.
Cd Ash, A.: A.
Sb Wet Ash, Spec.
Se Wet Ash, X.R.F.
Mo Ash, E.S.
Co Ash, E.S.
Ni Ash, E.S.
Pb Ash, A. A.
As Wet Ash, Spec.
Cr Ash, E.S.
Cu Ash, A. A.
Zr Ash, E.S.
B Ash, E.S.
Zn Ash, A. A.
V Ash, E.S.
Mn Ash, A. A.
F Wet Ash, S. I.E.
Symbols
LERC
(ID
SSMS
NAA
SSMS
SSMS
SSMS
C-a C-b
(12) (13)
_ _
Wet Ash, FAA
Ash, A. A.
Wet Ash, A...A.
Wet Ash, Fluorometry
SSMS
SSMS
SSMS/XRF
SSMS/XRF
SSMS/NAA
SSMS/XRF
SSMS
SSMS
SSMS/XRF
SSMS/XRF
SSMS/XRF
SSMS/XRF
Wet Ash, A. A.
Ash, Spec.
Batelle*
(14)
_
NAA
-
NAA
XRF
-
NAA
NAA/XRF
NAA/XRF
NAA/XRF
NAA
NAA/XRF
XRF
Berkeley* TRW
(15) (17)
_
IZAA
IZAA
NAA Wet Ash, Spec.
i
NAA
NAA
NAA Wet Ash, Spec.
IZAA
NAA Wet Ash, Spec.
NAA
SSMS Wet Ash, S.I.E.
A. A. -= Atomic-absorption spectroscopy
E.S. = Optical emission spectroscopy
F.A.A. = Flameless atomic absorption spectroscopy
Spec. = Spectophotometric
S.I.E. = Specific ion electrode
XRF - X-ray fluorescence
SSMS - Spark source mass spectrometry
NAA = Neutron activation analysis
IZAA = Isotope Zeeman atomic absorption spectroscopy
'
*SSMS,NAA,& XRF analyses were performed on raw shale powder.
12
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Despite the ranges and uncertainties in the data, approximate or
representative levels for most minor elements can be estimated. Tables 3-A
and 4 list mean values for two groups of minor elements, respectively, as
reported by or consolidated from several sources. The elements in the first
class (Table 3-A) were selected for major consideration because of (1)
potential environmental hazards which they may pose (2) their relative abun-
dance in conventional fossil fuels (e.g., coal) and associated processing or
waste streams. Elements in the second class (Table 4) generally pose less
of a hazard and/or are less abundant in fossil fuels. For the elements
in class 1, a summary of analytical techniques employed by the various labora-
tories is presented in Table 3-B.
The approximate mean levels for minor elements shown in Table 3-A and 4
have little meaning without a comparison with other geologic materials and an
identification of individual chemical forms or mineralogical residences. In
Table 5, mean levels of Group 1 elements in oil shale are compared to mean Bevels
in Piceance Basin soils and to average crustal abundances. Similar levelr
for many elements in oil shale and Piceance Basin soil is not surprising
since these soils were derived from oil shale and/or associated rocks.
However, Hg, Se, Mo, As, and F appear to be present in larger amou; Is ~r\
shale. Compared to average rocks of the earth's crust, oil shale is
enriched in Hg, Cd, Sb, Se, Mo, As, and B, and slightly depleted in Co,
Ni, Cr, Zr, and Mn (enrichment factors of .5 to 1.5 are considered within the
normal range of normal variation). For Class II elements (Table 4), only Li,
Cs, and Tl appear to be enriched to any degree in oil shale compared to common
rocks. Only three elements (Se, As, and V) are thought to exist at least in
part as components of kerogen in oil shale; the remainder exist as inorganic
trace minerals (e.g., zircon) or as substitute elements in major minerals
(e.g., pyrite).
The enrichment of oil shale in certain elements is consistent with data
for other sedimentary rocks containing organic material (e.g., coal). Elements
such as Mo, B, Zn, Cu, Se, are essential in small quantities for metabolic
activities in living plants and/or animals, and are therefore expected to have
been present in the parent organic debris from which the sedimentary rocks
were derived. Other elements such as Hg, Cd, and As, U, and V can form stable
13
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organic compounds or complexes, or can participate in ion exchange reactions
with organic material and become entrapped in the matrix of organic sediments,
After sediment deposition, entrapped elements may be altered chemically to
form inorganic compounds. Elements such as Cu, Zn, Ni, and Co may also be
enriched in sediments by precipitation as sulfides from groundwater which
contacts reducing organic material after deposition.
14
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Table 4. Mean Levels of Selected Trace Elements 1n Raw Oil Shale - Comparison of Reported Data
for Class II Clements* (ppm)
Element
Ti
Sc
Li
Rb
Cs
Ba
Sr
Y
Nb
Hf to Au
Tl
Ga
Ge
Sn
Te
Cl
Br
I
La to Lu
Th + U
U.S.G.S.
(MO)
1500
7
70
-
-
350
300
10
-
-
-
10
-
-
-
-
-
-
-
12
LERC
(11)
3600
6
15
no
0.2
650
900
20
6
1
1
10
2
3
.5
160
1
1
230
5
DRI
(18)
16
80
100
6
220
800
25
7
-
-
10
0.6
1
0.4
0.1
150
10
Battelle
(H)
-
6
-
67
5
350
400
-
-
1
-
7
-
-
-
-
-
-
120
10
Berkeley
(15)
-
6
-
88
7
540
-
-
-
-
-
-
-
17
Representative
Mean Value
2000
7
70
100
6
350
500
20
6
1
1
10
1
1
.5
160
0.6
0.5
150
10
Average
Crustal
Abundance(19
5700
22
20
90
3
425
375
33
20
1
.5
15
1.5
1
.5
130
2.5
0.5
150
12
Enrichment
Factor
0.4
0.3
3.5
1.1
2.0
0.8
1.3
0.6
0.3
-
2.0
0.7
0.7
1.0
-
1.2
0.2
1.0
1.0
0.8
*Class II Elements - Those which generally pose less of a potential environmental hazard than Class I
elements and/or do not tend to be relatively abundant in fossil fuels.
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Table 5. Mineralogical Residence and Relative Abundance of Selected
Trace Elements in Oil Shale (ppm)
Mineralogical Residence
Element 1n Oil Shale (2)
Be Unknown
Hg Unknown
Cd Cd$
Sb Unknown
Se Substitute for S in
Pyrite & Organic Matter
Mo Possibly sulfides
Co Substitute for Fe in
Pyrite
Ni NiS
Pb PbS or Fe Substitute
in Pyrite
As Substitute for S in
Pyrite, Organic Matter
Cr Substitute for Fe in
Pyrite
Cu Substitute for Fe in
Pyrite
Zr Zircon
8 Potassium Feldspar
Zn ZnS (sphalerite)
V Organic Matter
Mn Substitute for Fe in
Ferroan DolomitP.Sider-
ite.Magnesio-siderite
F Fluoride, cryolite
Representative
Mean Level
in
Raw Shale
1.5
0.4
1
1
1.5
10
10
25
20
35
34
37
40
65
70
100
250
1000
Average
Crustal
Abundance
(19)
2.8
0.8
0.2
0.2
0.05
1.5
25
75
13
1.8
100
55
165
10
70
135
950
625
_
Enrich-
ment
Factor
0.5
5
5
5
30
7
0.4
0.3
1.6
19
0.3
0.7
0.3
7
1.0
0.7
0.3
1.6
Average for
Soils in
Piceance Cr.
Basin (20)
2.4
.04
-
0.9
0.3
5
3
21
25
6
60
30
270
61
80
56
490
500
Enrich-
ment
Factor
0.6
10
-
1.1
5
2
.8
1.1
0.3
6
0.6
1.2
0.2
1.0
0.9
1.8
0.5
2
16
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2.4 LEVELS OF TRACE ELEMENTS IN PROCESSED OIL SHALE
Retorting of oil shale is generally effected by heating the rock to
temperatures of 800° -1000°F. Some minor elements in oil shale can form
volatile or oil soluble compounds at these temperatures and thus can appear
in shale oil, retort gases or retort waters. Most elements however, are
not volatile at retorting temperatues and are not converted into mobile forms
by the retorting process. Table 6 is a compilation of minor element composi-
tion data for processed oil shale as determined by several laboratories.
The data in Table 6 are mean levels and do not reveal the considerable ranges
of values from which the averages for individual laboratories were derived
The variations between laboratories reflect shale origin, analytical techniques,
and method of retorting. Within the limitations of the data, however, only the
elements Hg and Se appear to be depleted in processed shales compared to raw
shales by 70% or more. Cd, Sb, As, and Be and Zn appear to be depleted by
30% or more.
The depletion factors in Table 6 must be taken only as a rough indication of
element mobility in oil shale, since several elements (e.g., Co, Ni, Pb, Cr, and
B) are calculated to be more abundant in processed shale than in raw shale.
More reliable estimation of minor element retention or release by shale during
processing requires measurement of the same shale before and after processing
using equivalent analytical techniques. Even with such measurements, limits of
analytical precision, non-representativeness of samples, and sample
contamination from retorting or sample preparation equipment can obscure trends
in the data.
2.5 LEVELS OF TRACE ELEMENTS IN SHALE OILS
Minor elements in crude shale oils may be present in organic compounds or
complexes (e.g., As in arsines) or may be part of suspended shale fines (either
raw or retorted). Table 7 summarizes the available minor element data in
crude shale oils. As is the case with the data for raw and processed shales,
considerable variations occur between laboratories and individual shale oils.
Elements other than C, H, N, S, and 0 constitute a total of about 200-300 ppm
in a typical shale oil.
17
-------
Table 6. Mean Levels of Trace Elements in Processed Oil Shale
(Calculated as ppm raw shale basis*)
Element
Be
Hg
Cd
Sb
Se
Mo
Co
Ni
Pb
As
Cr
Cu
Zr
D
Zn
V
Mn
F
Ash,
Mahogany
Zone
Utah (4)
-
-
-
-
-
-
70
100
-
170
-
33
136
3b
78
420
-
Ash,
Mahogany
Zone
Colo. (21)
35
0.1
0.14
0.39
0.08
4.9
39
11
10
7.2
49
15
9.3
140
13
29
34
1700
Paraho
Direct
Mode
Retorted
Shale(lO)
2
0.07
-
0.7
0.3
12
13
38
18
21
136
44
43
52
16
116
600
1000
Paraho
Indirect
Mode
Retorted
Shale(lfl)
0.7
.03
-
0.8
0.2
10
16
14
11
18
66
26
62
18
21
88
272
450
Fischer
Assay
Retorted
Shale(22)
0.38
2.1
0.3
0.4
4.1
87
380
TOSCO II
Retorted
Sha1e(36)
4.9
38
38
42
105
62
108
Gas
Combustion
Retorted
£hale(14)
.002
2.7
2.9
17
56
80
73
42
106
100
Gas
Combustion
Retorted
Shale(15)
.04
0.56
7
8
19
34
58
244
270
Represen-Represen-
tatlve tat'ive
Mean Value for
Value Raw Shale
1
.04
0.5
0.5
0.3
10
16
38
34
25
100
26
43
100
35
00
250
900
1.5
0.4
1
1
1.5
10
10
25
20
35
34
37
40
65
70
100
1.0
1000
Deple-
tion
Factor
0.7
0.1
0.5
0.5
0.2
1.0
1.6
1.5
1.7
0.7
2.9
0.7
1.0
1.5
0.5
0.8
0.9
00
*Where ash equivalent of raw shale is not known a value of 0.8 is assumed for
calculations in this table.
-------
Table 7. Levels of Minor Elements in Shale Oils (ppm)
;
Class I
Elements
Be
Hg
Cd
Sb
Se
Mo
Co
Ni
Pb
As
Cr
Cu
Zr
B
Zn
V
Mn
F
Other
Elements
Fe
Ti
Al
8a
Mg
Ca
Na
Si
Gas Com-
bustion
Shale Oil
LERC(ll)
0.2
0.11
0.02
0.2
5-14
.8-7
2-55
0.4
.5-53
.2
.1-1.5
0.1
3
3
1
0.1
.1-3
8-390
1
.1-19
.1
.4-100
! .5-39
." 110
Gas Com-
bustion
Shale Oil
Battelle(14
.65
-
.008
.86
-
.37
90
5
.04
2.7
30 ' .
.01
1
|19
Gas Com-
bustion
Shale Oil
Paraho(23)
.02
.16
.2
.54
.08
-
-
2.4
.54
10
1.2
-
-
7
.075
5
4
-
_
36
36
21
14
12
-
Gas Com-
bustion
Shale Oil
USBM{24)
6.4
6.0
108
3as Com-
bustion
Shale Oil,
Berkeley(15)
.09-3.5
.01
.02
i
Gas Com-
bustion
Shale Oil,
Paraho(25)
2.5-2.9
20-22
0.33-.37
33-71
Gas Com-
bustion
Shale Oil
Paraho(26)
0.5
22-65
<3-30
TOSCO II
Shale
Oil(27)
,
6 1
40
3
100
i
Fischer
Assay
Shale
011(36)
0.2
1.1
7.8
24-29
< 1
.
6
Para ho
Indirect
Mode
Shale
Oil (27)
.5
35-65
60
Repre-
sentative
Level In
Shale Oil
.02
0.3
0.1
.02
.4
2
1
5
.5
20
.2
.5
.1
5
2
3
1
1
1
60
15
15
2
7
7
19
20
-------
Table 8. Approximate Percentages of Shale
Crude Shale Oil
Derived Minor Elements Which Appear in
Class I Elements
Be
Hg
Cd
Sb
Se
Mo
Co
Ni
Pb
As
Cr
Cu
Zr
B
Zn
V
Mn
F
Other Elements
ft
Al
Ba
Mg
Ca
Na
Si
Representative
Level in Shale
(ppm)
0.02
0.3
0.1
0.02
.4
2
1
5
Oil
20
.2
.5
.1
5
2
3
1
1
60
15
15
2
7
7
19
20
Quantity
in Shale Oil
per Ton Raw Shale
(10-6 ibs/ton)
4
60
20
4
80
400
200
1000
100
4000
40
100
20
1000
400
600
200
200
(10-6 Ibs/ton)
12000
3000
3000
! 400
1400
Quantity in
Representative
Raw Shale
(10-6 Ibs/ton)
4000
800
2000
2COO
3000
20000
20000
50000
40000
70000
70000
70000
90000
130000
140000
200000
500000
200000
(Ibs/ton)
40
2
60
0.8
80
1400 ' 280
3800 20
4000 300
Percent of
Element Contained
in Raw Shale
Appearing in
Shale Oil
,1
,5
0
7
1
8
3
2
1
2
.25
6
.06
.1
.02
0.8
.3
.3
.04
.01
.03
.15
.005
.05
.002
.0005
.02
.001
-------
Table 9. Comparison of Trace Element Levels in Shale Oil, Crude Oils, and
Residual Fuel Oil (ppm)
Element
Be
Hg
Cd
Sb
Se
Mo
Co
Ni
Pb
As
Cr
Cu
Zr
B
Zn
V
Mn
F
Fe
Ti
Al
Ba
Mg
Ca
Na
Si
Representative
Shale Oil
.02
0.3
0.1
.02
.4
2
1
5
0.5
20
.2
.5
.1
5
2
3
1
1
60
15
15
2
7
7
19
20
Petroleum Crude Oils (28)
Cal ifornia
23
0.056
0.36
13
98
0.66
0.64
.93
9.8
7.5
1.2
69
13
Libya
-
.055
1.1
.032
49
0.08
0.002
.2
63
8.2
0.8
4.9
13
i
i
1
Venezuela
0.03
0.30
0.37
7.9
0.18
117
0.28
0.43
.2
0.69
1100
0.2
4.8
20
Alberta
0.08
-
.009
.003
0.61
.002
-
-
0.67
0.7
0.05
0.7
3
Res idual
Fuel Oil 06 (29)
.0005 - .5
.002 - 0.4
.003 - 1
.003 - .5
.02 - 0.15
20 - 90
1 - 4
0.2 - 1
0.7 - 4
0.2 - 1
-
.002 - 0.2
.4 - 2
40 - 113
0.2 - 1
.004
10 - 20
-
-
0.3 - 5
2-3
.4 - 30
8-30
-------
A comparison of the representative quantities of minor elements in
shale oil.to those of raw oil shale is shown in Table 0. More than 57. of
Hg, Sb, and As and more than 1% of Cd, Se, Mo, Co. and Ni, originally present
in raw shale can be accounted for in crude shale oil. In contrast, less
than 0.001% of major raw shale elements Ca, Mg and Si are found in crude
shale oil. These data suggest that most of the Class I elements in shale
oil are not simply associated with suspended shale fines, but rather exist as
either organic complexes or as suspended insoluble minerals whose composition
differs from that of raw or retorted shale.
Although most Class I elements are enriched in shale oil relative to the
parent shale, their absolute levels in shale oil are in the same range as
or lower than those found in conventional petroleum crude and residual oils
(Table 9). A noteworthy exception is arsenic, which is found in significantly
higher concentrations in shale oils than petroleum oils(boron and fluoride also
appear to be present at higher levels, although the available data base is limited)
2.6 TRACE ELEMENTS IN RETORT GASES
The minor elements in oil shale may potentially be present in retort gas
gases in particulate or gaseous form. Raw or retorted shale particulate matter
may be suspended or entrained in retort gases, and such material would be
expected to have compositions similar to those discussed previously. Some
elements (e.g., Hg and As) can form volatile compounds at retorting temperatures
and may appear as either vaporous components of retort gases or as particulate
matter resulting from condensation of volatile substances during cooling of the
gas. Table 10 presents selected trace element analyses of LERC simulated in-
situ retort gas. Gaseous components are artificially defined as those not
retained by a 0.5u nucleopore filter and do not necessarily indicate gaseous
components. As calculated in the table, a very small fraction of As, Hg, Fe,
Cs, and Zn original in the shale appear in raw retort gases.
22
-------
Table 10. Levels of Minor Elements in Off-Gas Ffotn LERC Ten Ton Retort (14)
ro
oo
1
! i
Element Form
Arsenic
Mercury
Iron
Chromium
Zinc
Gas **
Particulate
Gas
Particulate
Gas
Particulate
Gas
Particulate
Gas
Particulate
Concentration
in Off -Gas
(pg/SCM)
15
0.4
15.4
2.2
0.15
2.35
120
6
126
90
2
92
40
0.5
40.5
Amount of Element
in Raw Shale
(grams/ton)
32
.36
18,000
34
Amount of Element
in Retort Gas
(mg/ton)
7.5
1.2
63
46
64 20
Percent of Element
Found in
Retort Gas
0.02
0.33
0.00035
0.14
0.03
* Assumes net gas production of 500 SCM/ton shale, Ref.(30).
**Gaseous forms are defined as those not collected by a 0.5u neopore filter.
-------
Table 11. Levels of Minor Elements in Retort Waters (ppm) Compared to Levels in
Selected Municipal Effluents and to Water Standards
Element
Be
Hg
Cd
Sb
Se
Mo
Co
N1
Pb
As
Cr
Cu
Zr
B
Zn
Li
V
Mn
F
Ba
Gas Combustion Simulated In-Situ Retorts
LERC(31) LERC(ll) LERC(14) LERC(15,16) LLL*(15,16)
.
.01
-
.007
.005
.47
.37
.26
.01
.26
.012
.003
.02
.26
.04
-
1.2
.023
-
.03
Fe . .49
»
.
< .01
.007
.01
.1
.07
1
.1
6
.02
.007
.07
6
.4
.3
.07
.1
25
.05
25
.39
-
.016
.98
-
.65
-
-
6
< .02
-
-
-
.43
-
-
-
-
.13
<1
1
.01
.001
.03
2
-
.2
5
.02
.003
0.1
0.3
-
5
1
Indirect Heated Retorts
TOSCO 11(32) Paraho I.D.M.(26)
-
-
-
.096
.006
.005
.03
< .002
1.0
.007
.16
.003
.44
.045
.006
.002
.019
.3
.09
5.7
.
-
-
-
0.7
0.1
< .04
.2
.2
1
.3
.2
-
5
Federal
Drinking
Water
Standards(33)
.002
.010
-
.01
-
-
-
.05
.05
.05
-
-
-
.4 5
1
.03
.3
7
2
5
-
-
1.4-2.4
1.0
-
Municipal/
Industrial
Final
Effluent
JWPCP(34)
.001
.036
-
< .01
.28
.25
< .01
0.8
0.4
1.0
1.45
0.13
10
Municipal
Final j
Effluent
Oxnard(34)
.0015
.017
.23
.07
.007
.044
.073
.21
0.12
0.5
Model Wastewater
Ordinance
Pretreatment
Standards (35)
.01
0.2
1.0
1.0
0.1
0.5
2.0
3.0
ro
* I.O.M. = Indirect Mode, LLL = Lawrence Liver-more Laboratory
-------
2.7 TRACE ELEMENT COMPOSITION OF RETORT MATER
Small quantities of shale df-ived elements are found in water which
condenses from retort gases or which separates from shale oil. Reported levels
in retort waters vary widely between retorting processes, laboratories, and input
shales. Generally, most elements are present at levels below 1 ppm in retort
waters although Zn, As, V, F, Ba, and Fe have been measured at hipher levels.
Table 11 summarizes some of the available data for waters produced by
simulated in-situ and by inert gas retorting processes. Minor elements may be
present as soluble inorganic salts, inorganic complexes, organometallic compounds, and
as insoluble suspended particulate matter. For most elements, the chemical form
in retort waters is unknown, although limited data suggest that 50% or more of
Hg, As, and Zn is particulate in nature (16).
Also listed in Table 11 are the levels 1) defined by Federal drinking water
standards, 2) found in the average final effluent from two California wastewater
treatment facilities, and 3) defined by model pretreatment standards.
Typical retort water would not meet the federal drinking
water standards, but would comply with a model pretreatment ordinance
for industrial wastewater, and compares favorably for many elements with the
quality of the treated effluent quality from a large metropolitan wastewater
treatment facility. However, retort waters may contain larger amounts of Hg,
As, B, and F than the example wastewater. Although the calculation's are not shown
in Table 11, the total quantities for individual elements in retort waters amount
to less than 1% of the quantities found in average oil shale.
3.0 TRACE ELEMENT MASS BALANCES AROUND OIL SHALE RETORTS
In the previous sections, several calculations have been performed to
estimate the fraction of selected elements which appear in the various oil shale
products after retorting. These calculations are crude at best, since the
average values used do not necessarily represent individual products der-;>/ed
from individual shales. Further, differences between laboratories and analytical
methods limit applicability of the mass balance approach to "average" data. In
part to avoid these problems, several investigators have attempted to obtain
trace element data under more controlled conditions so that mass balance estimates
can be performed with greater certainty. This section is a review and summary
25
-------
of recent work aimed specifically at estimating the mass balance of
certain minor elements around oil shale retorting processes.
3.1 ARSENIC
The U.S. Geological Survey retorted composite Mahogany Zone oil shale
(~30 - 35 gal/ton) by the standard Fischer technique and submitted the raw
and retorted shale samples to a commercial laboratory for analyses of
arsenic (2). The mean value (10 samples) for raw shale was 63 ppm, the
retorted shale 65 ppm (Table 12). Since the retorted shale represented 84%
of the weight of the raw shale, an average of 15% of the total arsenic was
apparently converted to volatile or oil soluble substances during pyrolysis.
Analyses of other Fischer Assay products for arsenic were not performed.
The Oil Shale Corporation (TOSCO) has reported arsenic levei'j in shale
oil produced by the TOSCO II retorting process. Table 13 summarizes the
arsenic content of this oil and its fractions (27). Because of the similar
pyrolysis conditions employed in the Fischer Assay and TOSCO II processes,
the oils produced by these processes should be similar in composition.
One ton of 35 gal/ton oil shale would yield a TOSCO II oil containing
.009 Ibs of arsenic. U.S.G.S. data indicate that the raw shale contains
about 0.13 Ibs of arsenic. Thus the shale oil contains about 7% of the
total arsenic originally present in the oil shale, a figure which agrees well
with the 6% calculated in Table 8 using averaged data for oil shales for various
shale oils. The quantity of arsenic in shale oil is somewhat lower than the
U.S.G.S. data would sugest assuming oil and retorted shale are the major
residences-for the element, although there is a large uncertainty (15% i 9% in
Table 12) in the data.
Recently the Lawrence Berkeley Laboratory (16) has constructed mass
balances for several minor elements around the LERC and LLL simulated in-situ
retorts. Table 14 summarizes the calculated distribution of six elements
(including As) among oil shale products. These data indicate that about 1%
of the arsenic originally present in raw oil shale appears in .product oil in
the gas combustion method of retorting. In contrast, arsenic mass balance data
in Table 15 for the Fischer Assay retorting process shows 6% of the arsenic is
found in that shale oil. The relatively low arsenic levels in LERC and LLL
shale oils (3-7 ppm) compared to the Fischer Assay Oil (~26 ppm) are not readily
explained by the differing methods of retorting. For instance, both Paraho Oil
26
-------
ro
Table 15. Distribution of Selected Trace Elements in Shale Products
During Fischer Assay Retorting (36)
Element
Se
Ni
Pb
As
Cu
Zn
Percent of
Raw Oil Shale
100
100
100
100
100
100
Element from Raw
Retorted Shale
90
91
96
94
107
87
Shale Which Appears
Crude Shale Oil
0.7
0.8
4.1
5.9
-
6.5
in Product
Retort Water
1.9
.3
N/A-
.07
.007
.01
-------
Table 12. Arsenic Analyses of Raw and Fischer Assay Retorted
Shale Samples (2)
Concentration in ppm
Raw Oil Shale
(10 Samples
Mean Standard 62.5
Standard Deviation 7.5
Range 55-75
Retorted Shale
(10 Samples)
64.5
4.4
60-70
Retorted Shale
(Raw Basis)
77.1
5.2
72-84
Difference
14.6
9.1
Table 13. Arsenic Levels in TOSCO II Shale Oil Fractions (27)
Boiling Range
°F
IBP -
400°-
900° +
Whole
400°
900°
Shale
°C
IBP - 200°
200°- 480°
480°+
Oil
Volume Fraction
%
18
58
24
100
Arsenic Content
ppm
10
52
38
41
28
-------
ro
Table 14. Distribution of Trace Elements in Oil Shale Products During Simulated
In-Situ Retorting (16,14)
Percent of Element from Raw Shale Which Appears in Product
Element
Hg
Cd
Pb
As
Cu
Zn
Retort
LERC
LLL
LERC
LLL
LERC
LLL
LERC
LLL
LERC
LLL
LERC
LLL
Raw
Shale
100
100
100
100
100
100
100
Retorted
Shale (16)
21
16
109
89
112
117
85
110
105
100
112
117
Crude Shale
Oil (Wet) (16)
7
26
.1
0.3
< .02
0.7
0.7
1.5
.07
2.0
< .02
0.7
Whole Retort
Water (16)
.7
0.5
.01
0.01
< .002
.01
0.06
0.4
.007
4.0
< .002
.01
Wet Product
Gas (14)
0.33
N/A
N/A
.02
.03
Imbalance in
The Data*
-72
-57
+ 9
-12
+12
+17
-14
+11
+ 5
+ 6
+12
+17
*Imbalance is the percent gain (+) or loss (-) in oil shale products compared to raw shale.
-------
1?
Direct Mode (gas combustion) and Paraho Indirect Mode (inert gas) contain about.
the same levels (20-30 pom).
Despite the unexplained differences in mass balance estimates, two major
conclusions can be drawn from the data: (1) 85 to 98% of the As in raw shale
is accounted for in retorted shale, and (2) As levels in crude shale oil (3-40 ppm)
are significantly higher than levels commonly encountered in petroleum crude
oils.
3.2 MEKCUfiY
Mercury is known to form a variety of relatively volatile compounds under
combustion and pyrolysis conditions. A SMirircary of several material balance
estimates for mercury around gas combustion retorts is shown in Table 14.
Retorted shale contains about 16-20% of the mercury input in raw shale; shale
oil contains 7-26% of input; retort water less than 1%. The Berkeley
investigators (16) postulated that the remaining mercury leaves the retort as a
component of product gases. Averaged data in Tables 6, 8, and 11 are consistent
with the Berkeley distribution of Hg among retorted shale, shale oil and retort
water. However, other investigators have reported very low levels of Hg in
retort gases (14). The apparent loss of Hg during retorting is not satisfactorily
explained by the existing data. Analytical bias (e.g., loss of Hg during oil
analyses), contamination from manometers, and/or Hg adsorption by walls of a
retort are possible explanations for the mass imbalance.
3.3 ZINC, LEAD, AND COPPER BALANCES
The data in Tables 14 and 15 indicate that essentially all of the Zn, Pb, and
Cu found in raw oil shale can be accounted for in retorted shale within analytical
uncertainties. Average data in Tables 3-A and 6 substantiate this finding. The
small amounts of these elements in shale oil are in the same range or lower than
those found in petroleum "crudes."
3.4 CADMIUM, SELENIUM, AND ANTIMONY BALANCES
Based on the data in Table 6, Cd, Se, and Sb, are depleted in retorted shale
compared to raw oil shale. The Berkeley data for cadmium in Table 14, however,
do not indicate such depletion for that element. The calculations in
Table 8 indicate that Cd, Se, and Sb in shale oil account for 1, 8, and
3 percent respectively of the amounts in raw shale. It appears that Cd
generally does not form volatile or oil soluble substances under retorting
30
-------
conditions, while selenium and, to a lesser extent, antimony do. These findings
are consistent with expected similarities in chemical properties between Cd and
Zn, Se and S, and between Sb and As.
3.5 OTHER ELEMENTS (Be, Mo, Co, Ni, Cr, Zr, V, Mn and F)
Mass balance studies have generally not been conducted for the above
elements. Available composition data for oil shale and its products are
not sufficient to accurately define the distribution of these elements. For
some elements (e.g., Be, Zr, Mo) the quantity of data are limited. For other
elements (e.g., B and F) the wide range of reported values in shale and its
products precludes accurate mass balance calculations. With these limita-
tions in mind, it appears that the elements above reside mainly in retorted
shales, and are not enriched in shale oils, retort gases, or retort waters
(Tables 6, 3, 10, and 11).
31
-------
4.0 THE DISPOSITION AND ULTIMATE FATE OF TRACE ELEMENTS CONTAINED IN OIL
SHALE PRODUCTS AND PROCESSING WASTES
In the previous sections, reported levels of minor elements in oil shale
and its products have been reviewed. This section is a discussion of the
expected disposition of these elements during commercial processing, end use,
and/or disposal of retort gases, shale oil, retort water, retorted shale,
shale oil coke, and non-shale products and wastes. In addition, the mobility,
chemical forms, and biological availability of some of the trace elements in
the above products and waste streams are predicted. For the purposes here,
retorting technologies are broadly classified as 1) gas combustion methods
(e.g., Paraho Direct Mode and Modified In-Situ), Indirect Heating methods
(e.g., TOSCO II and Paraho Indirect Mode).
4.1 RETORT GASES
Retort gases from gas combustion processes may be directly burned or
treated for sulfur removal prior to burning. As indicated by the limited data
in Table 10, the quantities of measured elements in gas combustion retort gases
are small. If the gases are directly burned, trace elements will be emitted to
the atmosphere primarily as particulate matter. If the gases are to be treated
for sulfur removal (e.g., by the Stretford Process) upgresam particulate
removal may be required to protect scrubber solution from degredation. Baghouses
or Venturi scrubbers would be expected to remove 95-99.9% of the total suspended
particulate matter. The elements in Table 10 may be less efficiently collected
than bulk particulate, since some (e.g., Hg) exist primarily as gases or as
particulates less than 0.5u in size. Particulates not collected prior to sulfur
removal are likely to be subsequently collected in scrubbing solutions used in
processes such as Stretford. Trace elements collected by particulate or sulfur
removal processes will become part or solid or aqueous wastes requiring
disposal.
In the TOSCO II process (or similar indirect heating methods), hydro-
carbon gases may be used for hydrogen production rather than as fuel. In
this case, trace elements in retort gases may be removed during aqueous or
32
-------
-oil scrubbing of the gases, or be physically trapped or chemically
reacted with catylist materials used for trace sulfur removal, water gas
shifting, or methanation. The scrubbing solutions and ultimately the
catalysts will require regeneration or disposal. Flue gases from the
preheat system of the TOSCO II retort will also contain trace elements,
although primarily in the form of raw or retorted shale particulate matter.
Such particulates would be collected by high energy Venturi scrubbers and
would constitute a solid waste.
4.2 RETORT
The data in Table 11 summarize trace element levels found in retort
waters from simulated in-situ and indirect heated retorts. Although the
quantities and forms of wastewaters requiring disposal depend on the
retorting process and the nature and extent of in-plant treatment and/or re-
use, the trace element levels in the table are somewhat indicative of those
which would be found in final plant wastewaters. Disposal of treated process
wastewaters would be accomplished by one or more of the following techniques;
1) direct discharge to surface waters, 2) ponding and evaporation, 3) under-
ground injection, and 4) moisturizing retorted shale.
The first method is generally not planned by oil shale developers,
although retort waters could likely represent an acceptable effluent from a
trace elements standpoint (see comparisons with other effluents and water
quality standards in Table 11). The second method will tend to concentrate
non-volatile substances in the pond(s), resulting in high levels of some
elements in the remaining water. Precipitation of less soluble forms of some
elements may decrease water concentrations at the expense of accumulation in
sediments. The third method, like discharge to surface waters, may be accept-
able from a trace elements standpoint, depending on the containment provided
by the accepting rock formation and/or the water quality of existing aquifers.
Ground water quality will be discussed later in connection with retorted
shale disposal .
33
-------
Finally, retort waters or process wastewaters may be used to
moisturize retorted shale. In this case trace elements contained in the
wastewaters would become components of a retorted shale disposal pile
where their mobility should be restricted. In principle, the alkaline
nature of retorted shale would tend to physically and chemically
immobilize most metalic elements. The mobility of elements such as Mo, F,
B, As, and Se which can form water soluble anionic species could, be mini-
mized by proper compaction to create an impermeable bed and by minimizing
infiltration of surface moisture into beds. Since moisturizing of processed
shale is the most commonly proposed method of wastewater disposal, the affect
of adding trace elements to retorted shale in wastewater form will be further
addressed in the next section.
4.3 RETORTED SHALE
Trace elements in retorted shale can be mobilized in several ways.
During transport and after surface disposal winds can suspend or
entrain fine particulate matter in the local atmosphere. Runoff from
retorted shale disposal piles can carry suspended sediment consisting of
retorted shale and shale/soil mixtures. Trace elements may also be trans-
ported by runoff as dissolved constituents (e.g., Mo, F, B). Surface mositure
and ground water can infiltrate a shale bed, dissolving certain trace inorganic
constituents. Finally, vegetation growing on retorted shale may extract cer-
tain trace elements from the bed, concentrate them in living tissues, and pass
o them on to herbavcrs which ingest the vegetation.
4.3.1 Fugitive Dust
The potential for atmospheric transport of trace elements in retorted
', shale is essentially unknown at present. With the possible exception of
i
mercury, most trace elements do not form known substances which are volatile
i at ambient temperatures. Thus trace elements would tend to be found in the
atmosphere primarily as components of raw and retorted shale particulate
matter. It is possible that certain elements may preferentially.reside in
^specific size fractions of retorted shales and thus be selectively favored
or disfavored for transport. Without specific data to indicate otherwise,
retorted shale particulate matter is expected to have the approximate com-
,position shewn earlier in Table 6. Compared to trace element levels in
34
-------
participate matter from "average" soils, only Se and As levels are likely to
be significantly higher in the retorted shale participates (see Tables 5 & 6).
4.3.2 The Water Solubility of Minor Elements in Retorted Shale
Experiments which have measured trace elements dissolved by water con-
tacting retorted oil shales fall into three general categories: (1)
laboratory "blender" experiments (2) laboratory column leaching experiments,
(3) field runoff and leaching tests. Data from several "bender" experiments
are summarized in Table 16 for selected elements. These data indicate that
Se, Mo, B, and F are present in retorted shale in partially water soluble
forms, while Cd, As, Cr, Cu, Zn, and Fe are essentially insoluble. Mith the
exception of As, the latter elements are general!} insoluble in aqueous
alkaline environments, since they form insoluble hydroxides, oxides, or
sulfides. The former elements however, can form water soluble anionic
species under alkaline conditions (e.g., SeO^= , Mo.=, B0,~3, F~).
The limited data bases used to construct Table 16 is not sufficient
to establish major differences in the water solubility of trace elements
between retorted shales produced by gas combustion and indirect heating
methods. The more alkaline nature of gas combustion shales would suggest
that most metals would be present in less soluble forms. On the other hand,
the carbonaceous residue associated with shales retorted by indirect heating
methods may physically inhibit contact and dissolution of substances from the
shale.
Laboratory column experiments more closely simulate conditions of water
contact which would occur in a retorted shale disposal pile than do
"blender" experiments. Figure 4 depicts the concentration of five elements
in the leachates from columns of TOSCO II retorted shale as a function of
water volume which has passed through the column. The total quantities of F,
B, Mo, As, and Se which are leached from TOSCO II shale in these column
experiments after 15 pore volumes have passed is approximately the same as
the quantities shown in Table 16. A distinct feature which is apparent from
the column experirr^'ots is that fluorine (as fluoride) is slowly Teachable from
35
-------
Table 16. Quantities of Minor Elements in Retorted Shale Which Are Water Soluble
According to Blender Experiments (ppm Retorted Shale Basis)
CO
Element
Cd
Se
Mo
Pb
As
Cr
Cu
B
Zn
F
Fe
Raw Oil
Shale (31,38)
2
0.4-7
3-60
TOSCO II
Retorted
Shale(38)
.05
8
0.1
12
80
Inert Gas
Retorted
Shale(37)
< .05
.14
< .05
.02
.005
Gas Com-
bustion
Retorted
Shale(37)
0.14
< .05
1.3
0.12
.03
LERC
Simulated
In-Situ
Retorted
Shale(31)
1.0
20
ILL
Simulated
In-Situ
Retorted
Shale(15)
.004
.003
.010
Representative
Level in
Retorted Shale
(from Table 6)*
0.5
0.3
10
34
25
100
26
100
35
900
20,000
Percent of ele-
ment in Retorted
Shale Which is
Water Soluble
0.8
17
2-80
.01-. 4
.4
.05-1
.04
1-12
.05-. 3
2-9
< .001
- -
*Data in Table 6 are calculated on a raw shale basis; for the accuracy intended here, the data are not
recalculated on a retorted shale basis.
-------
TOO
10 -
5- -
1
LJ
I i.o
'o
= .5
0.1- -
.05-
.01- -
.005- -
.001
I I
I I
4 6 8 10
Number of Pore Volumes Passing Column
0 1
12
Figure 4. Average Levels of F, B, Mo, As and Se in Leachates from
Columns Containing TOSCO II Retorted Shale(38)
37
-------
TOSCO II shale and maintains a level of about 10 mg/1 in leachate for
a considerable period of time. In contrast, Mo, As, and Se quickly
decrease in concentration in leachates. The data available at present
are not sufficient to indicate the rate of boron release from TOSCO II
retorted shale.
The Colony Development operation has sponsored studies of runoff and
leachates from field test beds of TOSCO II retorted shale (32)'. The low
permeability of compacted TOSCO II shale allows little of the incident
rainfall during a storm to penetrate a bed. Water which does penetrate
largely rises to the bed surface and is evaporated between rainfall events,
leaving surface salt deposits derived from soluble substances in the shale.
Runoff can redissolve these deposits and carry suspended and dissolved
materials to surface waters. In contrast to rainfall, snowmelt generally
occurs at rates slew enough to allow infiltration of most of the meltwater
into a TOSCO II shale bed. Infiltrated moisture tends to move as a front
into the shale and leachate may appear below shallow portions of a bed
(e.g., at the toes of slopes).
Table 17 summarizes measured trace element levels in runoff and
leachates from test beds of TOSCO II retorted shale. Concentrations in runoff
vary not only with storm duration and intensity, but also with the extent of
surface salt deposition which occurs between storms. In general, however,
the ranges of measured levels in runoff are similar to those which have been
reported for existing surface waters in and around the Federal lease tracts.
During natural storms or snowmelt at TOSCO's Rocky Flats, Colorado site,
leachate was not produced at the bottom of the test beds. The leachates for
which trace element levels are reported in Table 17 represent forced con-
ditions (e.g., continuous water application until leachate is produced).
As might be expected from the result of "blender" and "column" experiments,
Mo, B, F, As, and Se can be leached from TOSCO shale under saturated flow
conditions. In addition, the transition metals Cu, Zn, and Fe are present
in initial leachates in concentrations of 0.1 to 3 ppm.
In comparison to existing ground waters on the Federal lease tracts,
F and B levels are not unusually high in these leachates. However, Se, As,
Cu, Zn, and Fe are present at elevated levels. Although data for Mo in
existing groundwaters is not available, it is likely that the leachates also
contain significantly larger concentrations of this element.
38
-------
4.3.3 The Effects of Using Process Water to Moisturize Retorted Shale
The use of process waters to moisturize retorted shales can have two
potential effects on the quantities of trace elements which are water
soluble. First, additional amounts of some elements are added to shale
in water soluble form. Second, dissolved organic and inorganic substances
in process waters may affect the solubility of trace elements in the shale.
Table 18 is a comparison of the quantities of selected elements in LERC
and TOSCO II retort waters and the water soluble quantities of the same
elements in retorted shales. The data in the table suggest that significant
additions to the water soluble inventories of Mo, Pb, As, Cu, and Zn, in
retorted shale can occur using retort water as the moisturizing agent.
Generally, simulated in-situ (LERC) retort waters contain larger total
amounts of the listed elements than TOSCO II waters, partly because more
water is produced internally in the in-situ gas cOitribusriOT retort. 7he com-
parisons in Table 18 must be qualified by the fact that some trace elements in
retort waters exist partly as particulate matter rather than as dissolved
substances.
Dissolved organic and inorganic substances in retort waters can potentially
increase or decrease the solubility of individual elements in retorted shales.
Carboxylic acids, phenols, amines, cyanides, ammonia and other species found in
retort waters can form soluble complexes with many metals. The exact effects of
such substances in the retorted shale medium is difficult to predict, since
- both carbonaceous and burned shales partially absorb and immobilize many of the
'potential metal .complexing species. The chemistry of the retorted shale/retort
i 1
,^water medium is further complicated by the effects of salinity and alkalinity,
hi,
i^ and by precipitation reactions which occur. At present the net effect(s) of
if
'vretort water addition on the water solubility of most trace elements is
I unknown, since laboratory and field tests to date have not been designed to
A.measure such effects.
39
-------
Table 17. Levels of Trace Elements Measured in Runoff and Leachates from
Retorted Shale (ppm)(32)
Field Test Plots of TOSCO II
Element
Be
Hg
Cd
Sb
Se
Mo
Co
Ni
Pb
As
Cr
Cu
Zr
B
Zn
Li
V
Mn
F
Ba
Fe
1
First First
Runoff from Leachate Leachate
Typical from Sloping from Deepest
Rain Storms Section of Plot Portion of Bed
.0006
.00002-. 00007 .0005 .0003
.006 .003
.001-. 003 ' .002
.004-. 007 .002 - 2 2
.03 - .09 3-74 5-74
.01 .01 .001-. 04
.05 .05 -0.2 0.2 - 0.6
.009 .004 .003
.005-. 008 .02 .08 - .2
.01 - .07 .004-. 009 .004
.02 .06 - .2 .06 - .2
1001 .001 .003
.02 - .9 .02
.01 - .09 1 1-3
.02 - .2 .007-. 076 .07 -.8
.003 .003-. 006 .004-. 1
.004 .06 - .2 .06 - .5
.02-3 2-17 .006- 12
.02 -.04 .06 -.1 ' 0.1
.09 -.6 .6-2 1-3
Maximum Levels in
Surface Waters/Lease-Tracts
C-a C-b U-a/U-b
.001 .0008 .0002
.003 .006 .004
.006 .005 .002
.009 .011 .005
.009 .005 .002
.08 .02 .01
.008 .010 .013
0.77 0.33 0.09
10 1.3 0.3
0.40 .20 .14
Mean Levels in 6
C-a
Alluvial Upper Lower
Aquifer Aquifer Aquifer
.000 .000 .000
.03 .002 .001
.000 .000 .000
0.40 .35 .66
.000 .004 .001
.000 .005 .000
0.5 .03 .02
1.25 0.7 1.8
.37 4.1 14
.003 .000 .000
round Watei
Alluvial
Aquifer
.003
-
-
.026
.006
-
.7
.97
.09
s
C-h
Upper Lower
Aquifer Aquifer
.001 .001
-
-
.013 .034
.014 .13
-
1.5 3.0
18 19
.10 1.0
-------
Table 18. Comparison of Water Soluble Trace Element Quantities in
Retorted Shale to the Quantities in Retort Waters
Element
Cd
Se
Mo
Pb
! As
i Cr
i Cu
B
! Zn
i F
Quantity in *
Retorted Shale
which is
Water Soluble
(Mg/Kg)
.04
.05
< .05-8
.003 - .14
0.1
< .05-1.3
0.01
1 - 12
.02 - .12
20-80
Quantity in*
LERC
Retort Water
Added to Shale
(Mg/Kg)
< .0001
< .0005
.02
.005
0.14
.001
0.01
0.14
.02
1.1
Quantity in*
TOSCO II
Retort Water
Added to Shale
(Mg/Kg)
.
-
.003
.001
.001
.01
< .0001
< .0001
.01
.001
* Data from Table 16
** Data from Table 11, assumes
***Data from Table 11, assumes
45 liters of retort water produced per ton of raw shale
10 liters of retort water produced per ton of raw shale.
-------
4.3.4 The Accumulation of Trace Elements by Vegetation Growing on
Retprted_Shaie
The water solubility of specific trace elements in retorted shales
suggests that they may be available to vegetation growing on such shales.
The concern with trace element accumulation stems for both toxicity to plants
(e.g., B) and to herbivores (e.g., F, As, Mo, Se).
In 1973, revegetation test plots of TOSCO II and USBM retorted shales
were established at Parachute Creek (Colony property) and at Anvil Points.
In August of 1974, barley plants growing on shales at the Parachute Creek
site were sampled and analyzed for selected trace elements (Mn, Fe, Cu, Zn,
Sr, Zn, Mo, and Cd). Compared to a soil control, only molybdenum appeared to
be higher in barley growing on both retorted shales (42). Zn concentrations
also were higher in plants from the TOSCO II plot than in plants from native
soils.
During 1976, samples of wastern wheatgrass and four wing salt bush were
obtained from these plots and analyzed for B, F, As, Mo, and Se (41). Table 19
presents the typical analytical results for the above ground portions of
these plants based on dry weight of vegetation. Levels of molybdenum and boron
appear higher in wheatgrass grown on TOSCO II shale than on native soils. A
similar trend is not as apparent for USBM retorted shale. Molybdenum also
appears to be present at elevated levels in four wing salt bush grown in USBM
shale, at least at the Parachute Creek site. Fluorine levels in wheatgrass do
not show a strong trend for the retorted shale media compared to native soils.
The data for arsenic are not adequate to establish a trend, since a true
profile of native soil was not used as a control. Selenium data were not
available at the time of this writing. Samples of vegetation were taken from
both north.and south facing slopes, and the results show no obvious trends
within the accuracy and reproducibility of the analyses.
These studies suggest that available boron in retorted shales may exceed
the threshold of toxicity for sensitive plants, and that certain fluora may accumu-
late levels of molybdenum toxic to herbivors. For instance, many common fruit
trees exhibit symptoms of boron toxicity at 2 ppm levels (dry folige basis).
Domestic livestock begin to show symptoms of molybdenosis or, a diet of vegetation
containing 15-20 ppm Mo (low copper levels and high sulfate sulfur levels are
also involved in molybdenosis).
42
-------
Table 19. Trace Element Levels in Vegetation Grown on Retorted Shales (41)
(ppm dry weight plant material basis)
co
.
Location/Growth Medium
Parachute Creek
Natural soils
TOSCO II retorted shale
USBM retorted shale
Anvil Points
Natural soils
TOSCO II retorted shale
USBM retorted shale
Boron
25
100
H-93
19-115
200
40-70
Western Wheatgrass
Fluoride Arsenic
2 0.12*
3 0.2
3.5 0.3
2.4
5
4
Molybdenum
0.8
3
3
3
5
4
Four Wing Salt Bush
Molybdenum
6
7
27
3
2
6
*Natural soil (12") over TOSCO II retorted shale, similar levels found in wheatgrass grown on
24" natural soil ever USBM retorted shale
-------
4.4 CRUDE SHALE OIL
Crude shale oil may be directly used as fuel or refined into
other fuel or hydrocarbon products. During combustion, trace elements
contained in shale oil will appear as atmospheric emissions or will be
retained in combustion or pollution control equipment. During
refining of upgrading, trace elements will generally be captured by scrubber
solutions, filter media, distillation residues, or catalysts.
4.4.1 Combustion
Trace e)er,ient sampling of analyses of shale oil and its combustion
products have been performed during tests in an electric utility boiler system(23)
The material balance results from these tests shown in Table 18 suggest that for
several elements, large fractions of input quantities are either retained in the
boiler system or exit to the atmosphere in gaseous form. A wet lime scrubber is
used in the flue gas system to collect SO-, and 30% or more of the Se, Pb, As
B, F and total particulate matter is removed from the flue gas by the
scrubber.
Two elements (Zn and Se) appear to have been picked up in the boiler,
since levels in flue gases exceed the quantities measured in the input oil.
V, Mn, Mi and Sb appear to have been picked up during the scrubbing process,
perhaps from the lime reagent. The data indicate that all input Hg exits in the
effluent flue gas (within analytical uncertainty), while other elements are
either retained in ash or deposits within the boiler system, or leave as
gaseous components of effluent flue gases. The latter is not the favored
explanation since unaccounted for fractions of elements which are not known to
form volatile compounds at combustion temperatuees (e.g., Ca, Mg, Al, Ti, Ba, Be)
are similar to fractions for elements which might be expected to form volatile
compounds (e.g., Cd, Sb, Ni, Cr, Zn, Zr). If trare elements are deposited in
the boiler system, they may eventually exit in flue gas particulate matter when
deposits break up, or as residues from boiler tube and furnace cleaning
operations.
44
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Table 20. Trace Element Mass Balance During Combustion of
Crude Shale 011 (23)
Element
Be
Hg
Cd
Sb
Se
N1
Pb
As
Cr
B
Zn
V
Mn
F
Ba
T1
Al
Mg
Ca
1
ppm In
Shale 011
< .02
0.16
0.2
0.5
0.008
2.4
0.5
10
1.2
7
.08
5
4
13
21
36
36
14
12
Percent of Element
Found In Flue
Gas Partlculate
5
105**
6
2
1600
16
78
32
< 1.5
4
270
5
2
3
13
17
4
13
7
Percent of Element
Found In Scrubber Percent of Input
Gas Partlculate Not Accounted For
4 96
.110** i 0
4 ; . 94
5 ,95
600 ! * '
20 80
28 22
21 ' 68
<1.5 98
0.6 96
210 *
8 92
16 84
0.05 97
13 87
0.1 83
< 2 96
13 87
4 93
* Se and Zn appear to have been picked up 1n the boiler during these tests.
**Hg was collected as a gold amalgum rather than as particulate matter.
45
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4.4.2 Upgrading and Refining
On site upgrading or refining of crude shale oil planned for the first
generation of commercial operations consists of 1) filtration for solids removal,
2) distillation and coking, and/or 3) catalytic hydrogeneration of whole
shale oil or its fractions. Filtration (e.g., dicitomateous earth) will
generally remove insoluble inorganic materials and the trace element
components of such materials. As was discussed previously, however, only
a portion of the trace element levels in shale oil can be attributed to the
presence of raw or retorted shale fines.
In the distillation of shale oil, most minor elements tend to concen-
trate in the higher boiling fractions and in shale coke. Table 18 presents
data for the As, Ni, V, and Fe contents of TOSCO II and Paraho Direct
Mode shale oil fractions. Although the fraction analyses for Paraho oil are
not entirely consistent with whole oil analyses, the data show the trend
tov/ard higher levels of Ni, V, and Fe in higher boiling fractions. In
contrast, arsenic is apparently distributed throughout the boiling range.
In a commercial operation, elements such as Ni, V, Fe will tend to
concentrate along with shale fines in coke. Assuming that about 10% of
whole shale oil becomes coke during upgrading, a typical shale coke analysis
might be approximated by multiplying the values for non-volatile elements in
Table 7 for crude shale oil by ten. Volatile elements (As and probably Se,
Hg, and Sb) are likely to be found in lower boiling fractions at levels in the
same range as 1n whole shale oil.
Hydrotreating of shale oil for sulfur and nitrogen removal is typically
performed over nickel or cobalt molybdate catalyst supported on alumina.
Many metallic and heavy elements are known to decrease the activity of these
and similar catalysts. The levels of most elements which are encountered
in shale oils are generally similar to or less than those for many petroleum
crudes. Further, techniques have been developed in the petroleum industry to
avoid excessive catalyst deterioration due to the presence of certain trace
elements. The relatively high- arsenic levels in shale oils have necessitated
steps for its removal to maintain bulk catalytic activity during hydrotreating
operations. The steps generally employ a selective absorbant for As (and other
trace elements) or a portion of the catalyst bed itself as the removal media.
The contaminated media would be periodically removed for disposal or
reprocessing.
46
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Table 19. As, Ni, V, and Fe Distribution in Shale Oil
Distillation Fractions (27,25) (ppm by weight)
Boiling Range
IBP - 200°C
200°- 480°C
400°C +
Whole Shale Oil
TOSCO II
As
10
52
38
40
Shale 011/fcl
Paraho Paraho
As Ni
1.9
0.3
1.5
20 2.5
ement
Paraho
V
<.02
<.02
0.1
0.37
Paraho
Fe
7
8
36
71
47
-------
For Ni - Mo catalyst on alumina, 7% by weight of As would be the
approximate cutoff point for replacement, since at greater percentages As
begins to appear in the hydrotreated product. Spent catalyst would also
contain around 10% carbon, 8% sulfur and small quantities of other shale
derived elements (Sb, Se, and transition metals) (27,39). The chemical
form(s) of arsenic on spent catalyst is not known, although AS2S3 or elemental
As are likely candidates.
Spent catalyst would generally be disposed of with other solid wastes
in a commercial oil shale operation until sufficient quantities of such
materials could justify shipping to a preprocessor. In recent years, prices
for metals such as Ni, Co, and Mo have increased to the point where reclaimation
firms can offer attractive terms to refiners for spent catalysts (40). However,
contaminants such as arsenic in spent catalysts from shale operations may pre-
sent technical, economic, or waste disposal problems for reclaimers. Thus,
direct disposal with other wastes is the likely fate of these materials, at
least during the early stages of oil shale development. The quantities
requiring disposal is small relative to the quantities of retorted shale and
catalyst materials may be placed in steel drums for landfill, disposal as is a
common practice with spent petroleum catalysts, or mixed with retorted shale
and spread over a larger area in a disposal pile. At this time there is little
information to indicate the chemical stability or potential for mobility of
catalyst metals (Ni, Co, Mo) and trace element contaminants (As, Se, Hg)
disposed in either concentrated or dispersed form with retorted shale.
48
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REFERENCES
1. Matzick, A., et al., "Development of the Bureau of Mines Gas-Combustion
Oil Shale Retorting Process," U.S. Bureau of Mines Bulletin No. 635, 1966.
2. Desborough, G.A., "Pitman, J.K., and Huffman, C., "Concentration and
Mineralogical Residence of Elements in Rich Oil Shales of the Green River
Formation, Piceance Creek Basin, Colorado, and- the Uinta Basin, Utah --
A Preliminary Report," U.S. Geological Survey Open File Report 74-77, 1974.
3. Smith, J.W., "Ultimate Composition of Organic Matter in Green River Oil
Shale," U.S. Bureau of Mines Report of Investigation 5725, 1961.
4. Smith, J.W., and Stanfield.K.E., "Oil Yields and Properties of Green River
Oil Shales in the Uinta Basin, Utah," 13th Annual Field Conference,
Intermountain Association of Petroleum Geologists, p 213, 1964.
5. Brobst, D.A., and Tucker, J.D., "X-Ray Mineralogy of the Piceance Creek
Member, Green .River Formation, in the Northern Piceance Creek Basin,
Colorado," U.S. Geological Survey Prof. Paper 803, 1973.
6. Schramm, L.W., "Shale Oil, "Mineral Facts and Problems," 1970 Edition, U.S.
Bureau of Mines, Bull. 650, p 183, 1970.
7. Smith, J.W., "Theoritical Relationship Between Density and Oil Yield for
Oil Shales," U.S. Bureau of Mines Report of Investigation No. 7248, 1969.
8. Dyni, J.R., "Stratigraphy and Nahcolite Resources of the Saline Facies of
the Green River Formation in Northwestern Colorado," Rocky Mountain Association
of Geologists - 1974 Guidebook, p 111, 1974.
9. Robb, W.A., and Smith, J.W., "Mineral Profile of Oil Shales in Colorado
Corehole No. 1, Piceance Creek Basin, Colorado," ibid 15, p 91, 1974.
10. Unpublished data by James D. Vine, John R. Donnell, and John R. Dyni, of the
U.S. Geological Survey, Provided by John R. Donnell to TRW, March 1977.
11. Poulson, R.E., et al., "Minor Elements in Oil Shale and Oil Shale Products,"
presented at the NBS/EPA Workshop on Standard Reference Materials for Oil-
Shale Environmental Concerns, Gaithersburg . Md. November 1975.
12. Rio Blanco Oil Shale Project, 230 samples of fresh shale from lease T^act
C-a, 1975.
13. C-b Shale Oil Project, 140 samples of fresh shale from lease Tract C-b,
1975.
14. Fruchter, J.S., et al., "High Precision Trace Element and Organic Constituent
Analysis of Oil Shale and Solvent-Refined Coal Materials," ACS Symposium on
Analytical Chemistry of Tar Sands and Oil Shale, New Orleans, La.,
March 20-25, 1977.
15. Fox, J.P., et al., "Water Conservation with In-Situ Oil Shale Development,"
University of California, Berkeley, Quarterly Report to ERDA; December 1,
1976 to February 28, 1977.
49
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16. Fox, J.P., et al., "The Partitioning of As, Cd, Cu, Hg, Pb, and Zn During
Simulated In-Situ Oil Shale Retorting," presented at the 10th Oil Shale
Symposium, Colorado School of Mines, Golden, Colorado, April 21-22, 1977.
17. Analyses of raw oil shale from Anvil Points Colorado mine by TRW, Inc.,
November 1976.
18. Analyses by Denver Research Institute (DRI) of retorted shales produced by
the Paraho Retort at Anvil Points, Colorado, September 1976.
19. Taylor, S.R., "Abundance of Chemical Elements in the Continental Crust: A
New Table," Geochemica et Cosmoschimica Acta, Vol. 28, p 1273-1287, 1974.
20. Ringrose, C.D., et. al., "Soil Chemistry in the Piceance Creek Basin,"
unpublished work conducted by the Department of Chemistry and Geochemistry,
Colorado School of Mines, in conjunction with the U.S. Geological Survey,
Paper provided by John R. Donnell of the U.S.G.S.
21. Cook, E.W., "Elemental Abundances in Green River Oil Shale," Chemical
Geology, Vol. 11, p 321, 1973.
22. Rio Blanco Oil Shale Project, "Detailed Development Plan for Tract C-a,"
Vol. 2, March 1976.
23. Data from tests with Paraho Shale Gil (Paraho Development Corp.,
private communication).
24. U.S. Pat. No. 3523073.
25. Bartick, H., et al., "Final Report on the Production and Refining of Crude
Shale Oils Into Military Fuels," Applied Systems Corporation, August 1975.
26. Analyses performed by TRW and DRI on samples obtained at the Paraho Facility
at Anvil Points, Colorado, March 1976.
27. Burger, E.D., "Prerefining of Shale Oil," American Chemical Society Symposium
on Refining of synthetic crudes, Chicago, 111., August 24-29, 1975.
28. Filby, R.H., et al, "Newtron Activation Methods for Trace Elements in Crude
Oils," in The Role of Trace Metals in Petroleum, Ann Arbor, Sci Pub. Inc.,
1975.
29. Von Lehmden. D., et al., "Determination of Trace Elements in Coal, Fly Ash,
Fuel Oil, and Gasoline - A Preliminary Comparison of Selected Analytical
Techniques," Anal Chem, Vol 46, No. 2, p 239-245, February 1974.
30. Harak, A.E., et al., "Oil Shale Retorting In A 150-Ton Batch-Type Pilot
Plant," U.S. Bureau of Mines Report of Investigations No. 7995, 1974.
31. Jackson, L.P., et al., "Characteristics and Possible Roles of Various Waters
Significant to In-Situ Oil Shale Processing," Proceedings of the Environmental
Oil Shale Symposium, Colorado School of Mines, Golden, Colorado, Vo 70, No. 4
October 1975.
50
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32. Metcalf and Eddy Engineers, "Water Pollution Potential from Surface
Disposal of Processed Oil Shale from the TOSCO II Process," A Report
to the Colony Development Operation, October 1975.
33. Federal Register, Vol. 40, No. 248, Wednesday, December 24, 1975.
34. Southern California Coastal Hater Research Project, Annual Report for the
Year Ended June 1976, El Segundo, California.
35. Model Wastewater Discharge Ordinance, Industrial ^iaste CO-TV,.1V.et. California
Water Pollution Control Association, April 1974.
36. Wildeman, T.R., "Mass Balance Studies on Oil Shale Retorting," Progress
Report June 1, 1976 - May 31, 1977 to ERDA, Colorado School of Mines,
Golden, Colorado.
37. Parker, H.W., et al., "Simulated Ground Water Leaching of In-Situ Retorted
or Burned Oil Shale," American Chemical Society Symposium on Oil Shale,
Tar Sands, and Related Materials, Vol. 21, No. 6., San Francisco, Calif.
August 29-September 3, 1976.
38. Runnells, D.D., et al., "Release, Transport, arid Fate of Some Potential
Pollutants," Progress Report June 1, 1976 - May 31, 1977 to ERDA, University
of Colorado, Fort Collins.
39. Colony Development Operation, "Draft Environmental Impact Analysis for A
Shale Complex at Parachute Creek, Colorado, Part 1," 1974.
40. Millensifer, T.A., "Recycling Spent Catalyst Becomes Attractive as Metal
Prices Rise," Oil and Gas Journal. March 28, 1977
41. McFadden, R.E., "Availability of As, Se, B, Mo and F to Plants Growing on
Revegetated Spent Shales of Western Colorado During 1976," Progress Report to
ERDA, Colorado State University, May, 1976.
42. Harbert, H.P., and Berg, W.A., "Vegetative Stabilization of Spent Oil Shale,"
Colorado State University Environmental Research Center, Technical Report
No. 4, Fort Collins, Colorado, 1974.
51
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA 908/4-78-003
2.
3. RECIPIENT'S ACCESSION-NO.
4. TITLE AND SUBTITLE
Trace Elements Associated wi
And Its Processing
h Oil Shale
5. REPORT DATE
May 1977
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
TRW/DRI
8. PERFORMING ORGANIZATION REPORT NO,
9. PERFORMING ORGANIZATION NAME AND ADDRESS
TRW DRI
Los Angeles, Calif. Denver, Colo
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-02-1881
12. SPONSORING AGENCY NAME AND ADDRESS
EPA
IERL-Cincinnat1
Cincinnati, Ohio 45268
13. TYPE OF REPORT AND PERIOD COVERED
Final 1975-1977
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
Contact Mr. Tom Powers
Mr. Terry Thoem
16. ABSTRACT
This report includes a summary of existing trace element
composition data for shale and its products, an evaluation of
these data and related studies to estimate the distribution of
trace elements among shale products during oil shale processing,
and predictions of the disposition and ultimate fate of trace
elements after waste disposal or product use. Wide ranges in
trace element concentration reflect natural geographic and
vertical profile variations in shale.
7.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Group
Oil Shale
Trace elements
Oil Shale
8. DISTRIBUTION STATEMENT
Release unlimited
19. SECURITY CLASS (ThisReport)
Tine.! assified
21. NO. OF PAGES
20. SECURITY CLASS (Thispage)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
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