EPA-600/2-77-206
October 1977
Environmental Protection Technology Series
           PILOT  PLANT  STUDY OF CONVERSION
                  OF COAL  TO  LOW SULFUR FUEL
                              Industrial Environmental Research Laboratory
                                    Office of Research and Development
                                   U.S. Environmental Protection Agency
                              Research Triangle Park. North Carolina 27711

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                    RESEARCH REPORTING SERIES
Research reports of the Off ice of Research and Development, U.S. Environmental Protec-
tion Agency, have been grouped into nine series. These nine broad categories were
established to  facilitate further development and application of environmental tech-
nology. Elimination of traditional grouping was consciously planned to foster technology
transfer and a maximum interface in related fields. The nine series are:

          1. Environmental Health Effects Research
          2. Environmental Protection Technology
          3. Ecological Research
          4. Environmental Monitoring
          5. Socioeconomic Environmental Studies
          6. Scientific and Technical Assessment Reports (STAR)
          7. Interagency Energy-Environment Research and Development
          8. "Special" Reports
          9. Miscellaneous Reports

This report has been assigned to the ENVIRONMENTAL PROTECTION TECHNOLOGY
series. This series describes research performed to develop and demonstrate instrumen-
tation, equipment, and methodology to repair or prevent environmental degradation from
point and non-point sources of pollution. This work provides the new or improved tech-
nology required for the control and treatment of pollution sources to meet environmental
quality standards.
                             REVIEW NOTICE
This report has been reviewed by the participating Federal Agencies, and approved for
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policies of the Government, nor does mention of trade names or commercial products
constitute endorsement or recommendation for use.

This document is available to the public through the National Technical Information
Service, Springfield, Virginia 22161.

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                                             EPA-600/2-77-206
                                                  October 1977
PILOT  PLANT STUDY OF CONVERSION
    OF  COAL TO  LOW  SULFUR  FUEL
                            by

                  Donald K. Fleming and Robert D. Smith

                      Institute of Gas Technology
                      3424 South State Street
                      Chicago, Illinois 60616
                      Contract No. 68-02-1366
                       ROAP No. 21AFJ-040
                     Program Element No. 1AB013
                   EPA Project Officer: Lloyd Lorenzi, Jr.

                Industrial Environmental Research Laboratory
                  Office of Energy, Minerals, and Industry
                   Research Triangle Park, N.C. 27711
                         Prepared for

                U.S. ENVIRONMENTAL PROTECTION AGENCY
                  Office of Research and Development
                      Washington, D.C. 20460

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                                 DISCLAIMER


     This report has been reviewed by the Industrial Environmental Research
Laboratory, U.S. Environmental Protection Agency,  and approved for publication.
Approval does not signify that the contents necessarily reflect the views and
policies of the U.S. Environmental Protection Agency, nor does mention of
trade names or commercial products constitute endorsement or recommendation
for use.

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                              EXECUTIVE SUMMARY


     The purpose of this program is to develop, on a bench and pilot scale,
the operating conditions for the key step in the IGT process to desulfurize
coal by thermal and chemical treatment.  This process, to date, uses the
"sulfur-getter" concept.  A sulfur-getter is defined as a material that has
a greater chemical affinity for sulfur than the coal has.  Lime has been
selected as the sulfur-getter for this program.

     The program reported here was divided into two phases.  In Phase I, the
problem was directly attacked on a pilot-unit scale.  The results of this work
indicated that the program should be redirected (Phase II) to smaller-scale
test apparatus so that more basic data could be obtained for eventual scale-up
to pilot scale.

     In the initial project phase, a coal-lime mixture was experimentally
treated at atmospheric pressure with a reducing gas in a heated, fluidized-bed
reactor.  This reactor could treat up to 200 Ib/hr* of mixture to temperatures
of 1200°F.  The coal used in the in:
seam and contained about 3% sulfur.
of 1200°F.  The coal used in the initial tests was from the Illinois No.  6
     Work in the initial program phase resulted in the discovery that less
sulfur was removed than expected at these conditions.  Two factors were
believed responsible:

1.   The coal heat-up rate in the fluidized bed was nearly instantaneous,
     which appeared to cause organic sulfur fixation.

2.   The coal showed signs of weathering; therefore, the total sulfur content
     was not readily available for hydrogen treatment.

     At this point, the program was redirected (Phase II) to the operation of
smaller-scale test units that featured controlled heat-up rates.  The smaller-
scale units also permitted an increased number of tests over a broader range
of conditions, with savings in time and manpower.  Coal samples from several
mines throughout the country were obtained for tests in this equipment.

     A coal-lime mixture was treated with hydrogen, in batch-type reactors,
to temperatures of 1500°F.  Heat-up rate, terminal temperature, residence
time, and particle size were the variables tested.
* English units are commonly used in this document in areas of engineering
  development; SI units are used in more basic research areas.  Refer  to
  Conversion Table page xi.
                                     iii

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     Preliminary tests eliminated the Western coals (i.e., subbituminous and
lignite) because the sulfur content of the raw coal was low and not readily
amenable to treatment.  Also, the preliminary tests indicated that the coals
from the Midwestern and Eastern United States required pretreatment to prevent
caking during hydrotreating.  This is accomplished by heating the fluidized
coal at atmospheric pressure to 750°F in the presence of oxygen.

     On the basis of the preliminary tests with several coals and the relative
abundance of the types of coal, a coal from the Western Kentucky No. 9 seam
was chosen for complete characterization.  This coal is from the Illinois
basin and contains over 3% sulfur.  Tests were run covering a wide range of
the parameters listed.  These tests prove that acceptable sulfur levels were
attained at treatment temperatures of 1500°F.  The higher temperatures result
in significant tar removal and some gasification of the coal.  These effects
necessitate further research into quantity, chemical makeup, and handling of
gas' and liquid streams.

     The testing resulted in the discovery that treatment with lime does not
capture all the sulfur that is released from the coal.  A more thorough
examination of the effectiveness and benefits of lime is required in future
work.

     A conceptual process design, based on laboratory and bench-scale data, is
presented.  That process will produce a solid fuel that can be burned directly
in conformance with Federal EPA New Source Performance Standards (NSPS).
                                     iv

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                              TABLE OF CONTENTS
 Executive  Summary                                                     iii
 List of Figures                                                        vi
 List of Tables                                                       viii
 Conversion Factors                                                     xi
 Symbols                                                               xii
 Obj ective                                                               1
 Introduction                                                            2
 Materials                                                               3
     Coal                                                               3
     Acceptor                                                           3
     Mixture                                                           10
 Thermodynamic Study                                                    11
 Equipment                                                              29
     Pilot Unit                                                        29
     Batch Reactor                                                     29
     Thermobalance                                                     29
     Modified Batch Reactor                                            38
 Laboratory Procedures                                                  42
 Test Runs  — Start of Phase I                                           45
     Batch Reactor                                                     45
     Pilot-Unit Tests                                                  45
     Test  Results - Batch Unit                                         46
     Test  Results — Pilot Unit                                         52
     Analysis of Test Results                                          61
     Conclusions                                                       61
 Kinetic Studies of Outside Data                                        63
 Program Redirection — End of Phase I, Start of Phase II                70
 Selection  of Coal for Extensive Study                                  74
     Thermobalance Tests — Western Kentucky No. 9                      80
     Thermobalance Tests — Pittsburgh Seam, West Virginia              94
     Batch Reactor Tests — Western Kentucky No. 9                     112
     Batch Reactor Tests — Pittsburgh Seam, West Virginia             115
     Gas Sample Analysis                                              127
           Batch Reactor                                               127
           Pilot Reactor Runs                                          127
           Modified Batch Reactor                                      127
           Conclusions                                                 136
Process Concept                                                       137
Future Work                                                           139
     Necessity for Lime                                               139
     Other Coals                                                      139
     Pilot Unit                                                       139
     Overall Concept Design                                           139
References Cited                                                      140

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                               LIST OF FIGURES

Number                                                                   Page
   1      Fluidization Characteristics of Illinois No.  6 Coal,
            —10 Mesh	     6
   2      Fluidization Characteristics of Tymochtee Limestone .....     7
   3      Fluidization Curve for Mixed Coal-Limestone (25% +14
            Mesh Limestone and 75% —10 Mesh Coal)	     9
   4      Thermodynamic Equilibrium in Coal-Getter Process for
            FeS + CaO and FeS + H_ Reactions	    10
   5      Thermodynamic Equilibrium in Coal-Getter Process for
            H-S + CaO Reactions	    11
   6      Thermodynamic Equilibrium in Coal-Getter Process for
            FeS + CaCO- Reaction	    12
   7      Thermodynamic Equilibrium in Coal-Getter Process for
            CaCO, and CaS + H»0 Reactions	    13
   8      CaS-CaO-C02-H20 System  	    27
   9      CaO-CaS-C02 System  	 .    28
  10      Reactor Flow Sheet	    30
  11      Distribution Plate Detail 	    31
  12      Distributor. Plate	    32
  13      Distributor Nozzles 	    33
  14      Flow of H» in Distributor Nozzle	    34
  15      Distributor Plate Nozzle Pressure Drop Versus Reactor
            Gas Velocity	    35
  16      Treated Coal Receiver	    36
  17      Batch Coal Desulfurization Equipment  	    37
  18      Flow Diagram of Thermobalance System	    39
  19      Modified Batch Reactor  	    40
  20      Modified Batch Reactor Flow System  	    41
  21      Laboratory Procedure for the New Analytical Method  	    44
  22      Percent Pyritic Sulfur in Treated Coal  	    62
  23      Percent Total and Organic Sulfur in Treated Coal  	   62
                                     vi

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                        LIST OF FIGURES (Continued)

Number                                                                   Page
  24      Removal of Pyritic Sulfur	    64
  25      Removal of Nonfixed Organic Sulfur  	    64
  26      Fixation of Available Organic Sulfur as a Function of
            Temperature and Lime Content	    65
  27      Fixation of Organic Sulfur With Excess CaO Present  	    65
  28      Fixation of Organic Sulfur With Insufficient CaO Present  . .    66
  29      Coal Sulfur Fractions Heated Without Lime in the
            Presence of Hydrogen  	    68
  30      Coal Sulfur Fractions Heated With High Lime Additions
            in the Presence of Hydrogen	    69
  31      Thermobalance Char-Sulfur Content at 5 F/min Heating
            Rate	  102
  32      Thermobalance Char-Sulfur Content at 10° and 20°F/min
            Heating Rates 	  103
  33      Batch Reactor Char-Sulfur Content 	  123
  34      Flow Sheet for Proposed Process	  138
                                     vii

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                               LIST OF TABLES
Number
   1      Raw Coal Analysis ......................     4
   2      Sulfur in Coal by Type  ...................     5
   3      Limestone Analysis  .....................     8
   4      Case I (0.3 mole CaS, 1 mole CaO, 3 moles H20)  .......    18
   5      Case II (0.3 mole CaS, 3 moles H-O, 3 moles C02, 1 mole CaO).    19
   6      Case III (1 mole CaO, 0.3 mole CaS, 3 moles CO,)  ......    21
   7      Case IV (0.3 mole CaS, 1 mole CaO, 3 moles S02) .......    23
   8      Case V (0.3 mole CaS, 1 mole CaO, 1 mole 02)  ........    26
   9      Float Portion of Batch Tests  ................    47
  10      Sink Portion of Batch Tests .................    49
  11      Batch Test Run 20 ......................    51
  12      Batch Test Gas Sample Analysis  ...............    51
  13      Pilot-Unit Run Conditions ..................    53
  14      Size Analyses of Pilot-Unit Test 2  .............    54
  15      Sample Analyses for Run 3 (N2, 600°F, Without Lime) .....    55
  16      Sample Analyses for Run 4 (N2, 800°F, Without Lime) .....    55
  17      Pilot-Unit Run 5 (NZ, 825°F)  ................    56
  18      Pilot-Unit Run 6 (N2 and H2> 850°F, 50 Ib/hr Coal) ......    56
  19      Time-Temperature Matrix for Pilot-Unit Runs .........   57
  20      Pilot-Unit Run 7 (H2, 1000°F, 50 Ib/hr Mix) .........   58
  21      Pilot-Unit Run 7, Further Detail   ..............   58
  22      Pilot-Unit Run 8A (H2> 900°F, 50 Ib/hr Mix) .........   59
  23      Pilot-Unit Run 8B (H , 750°F, 50 Ib/hr Mix) .........   59
  24      Pilot-Unit Runs 9A and 9B (H2, 950°F, 50 Ib/hr Mix) .....   60
  25      Pilot-Unit Run 9C (H2, 800°F, 50 Ib/hr Mix) .........   60
  26      Basic Data — Thermobalance Runs ...............   71
  27      Thermobalance Runs — Reduced Data  .  .............   72
  28      Thermobalance Run Data (Illinois No. 6 Coal)   ........   75
                                    viii

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                         LIST OF TABLES (Continued)






Number                                                                   Page
29
30
31
32

33

34

35

36

37

38

39

40

41

42

43
44
45

46

47

48

49

Thermobalance Run Data — Various Coals 	
Thermobalance Run Data (Western Kentucky No. 9) 	
Thermobalance Run Data (Pretreated Western Kentucky No. 9) .
Thermobalance Run Data (Pretreated Western Kentucky No. 9
Coal, 900°F) 	
Thermobalance Run Data (Pretreated Western Kentucky No. 9
Coal, 1500°F) 	
Thermobalance Run Data (Pretreated Western Kentucky No. 9,
1500°F, 30 min) 	
Thermobalance Run Data (Pretreated Western Kentucky No. 9,
1500°F, 0 min) 	
Thermobalance Run Data (Pretreated Western Kentucky No. 9,
10°F/min, 1500°F) 	
Thermobalance Run Data (Pretreated Western Kentucky No. 9,
20°F/min, 1500°F) 	
Thermobalance Run Data (Pretreated Western Kentucky No. 9,
1300°F) 	
Thermobalance Run Data (Pretreated Western Kentucky No. 9,
1600°F) 	
Thermobalance Run Data (Pretreated Pittsburgh Seam, W. Va.,
1500°F, 0 min) 	
Thermobalance Run Data (Double Pretreated Pittsburgh Seam,
W. Va., 1500°F) 	
Thermobalance Run Data (Pretreated Pittsburgh Seam, W. Va.,
1500°F, 0 min) 	
Thermobalance Run Data (Pretreated Pittsburgh Seam, W. Va.).
Batch Reactor Run Data (Western Kentucky No. 9) 	
Batch Reactor Run Data (Pretreated Western Kentucky No. 9,
900°F) 	
Batch Reactor Run Data (Pretreated Western Kentucky No. 9,
1500°F) 	
Batch Reactor Run Data (Pretreated Western Kentucky No. 9,
1300°F) 	
Batch Reactor Run Data (Pretreated Western Kentucky No. 9,
10° and 20°F/min) 	
Batch Reactor Run Data (Pretreated Western Kentucky No. 9
Rapid Heatup) 	
76
81
85

86

87

90

92

95

96

99

101

105

106

109
110
113

114

116

118

120

122
                                     ix

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                         LIST OF TABLES (Continued)


Number                                                                   Page

  50      Batch Reactor Run Data (Pretreated Pittsburgh Seam,
            W. Va.)	    124
  51      Batch Reactor Gas Analysis — Illinois No. 6 Coal	    128

  52      Pilot Reactor Gas Analysis — Illinois No. 6 Coal	    129

  53      Modified Batch Reactor Gas Analysis (800°F) — Pretreated
            Western Kentucky No. 9 Coal	    130

  54      Modified Batch Reactor Gas Analysis (1200°F) — Pretreated
            Western Kentucky No. 9 Coal	    131

  55      Modified Batch Reactor Off-Gas Analysis (1500°F) -
            Pretreated Western Kentucky No. 9 Coal	    132

  56      Modified Batch Reactor Off-Gas (800°F) — Pretreated
            Pittsburgh Seam (W. Va.) Coal	    133

  57      Modified Batch Reactor Off-Gas (1200°F) - Pretreated
            Pittsburgh Seam (W. Va.) Coal	    134

  58      Modified Batch Reactor Off-Gas (1500°F) - Pretreated
            Pittsburgh Seam (W. Va.) Coal	    135

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                             CONVERSION FACTORS
Non SI Units
atmosphere
Btu
Btu/lb
cal
°C
°F
°F/min
foot
inch
in H20
in H20/ft
pound
psi(a)
SCF/hr
               Operation
         x  101325
         x  1055.87
         x  2327.794888
         x  4.19002
         +  273.15
         (5/9)(TF + 459.67)
         x  .0092592
         x  0.3048
         x  0.0254
         x  249.082
         x  2988.98
         x  0.45359237
         x  6894.7572
         x  0.000007865790722
SI Unit
 N/m2
   J
 J/kg
   J
   K
   K
  K/s
   m
   m
 N/m2
 N/m3
  kg
 N/m2
 m3/s
Mesh
An Empirical Measure of Particle Size:
U.S.
Mesh
10
12
14
20
30
40
60
80
100
Opening Size
mm
2.00
1.68
1.41
0.84
0.59
0.42
0.25
0.177
0.149
                                     xi

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                         SYMBOLS


Symbol             Meaning

  Cp               Heat capacity

  K                Equilibrium constant (when not preceded
                   by a numeral)

  N                Solution normality
                          xii

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                                  OBJECTIVE
     The objective of the program is to determine experimentally, on a bench-
and pilot-unit scale, the operating conditions for the key step in the IGT
process to desulfurize coal by thermal and chemical means.  The current NSPS
for solid fossil-fuel combustion has largely been observed by switching to
low-sulfur fuels.  Achieving the goals of this program will increase the
supply of low-sulfur fuels.

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                                INTRODUCTION


     Researchers at the Institute of Gas Technology (IGT) have conceived a
process for the removal of sulfur from coal by thermal and chemical means.
A patent has been granted on this process and assigned to IGT.  The objective
of the current work in this program has been to develop the key step of that
process.

     The process incorporates low-pressure treatment of the coal in a reducing
atmosphere, forming hydrogen sulfide (H2S).  The equilibrium partial pressure
of H2S over coal is not high, even at elevated temperatures.  In this process,
therefore, a "sulfur-acceptor" ("sulfur-getter") is added to the coal-
reductant system.  The sulfur-getter is defined here as a material that has a
greater chemical affinity for sulfur than coal has, thus overcoming the
equilibrium limitations.  One example of a sulfur-getter is lime.  Hydrogen
sulfide has a much lower equilibrium partial pressure over lime than it has
over coal; therefore, the reducing gas will react with the sulfur in the coal,
forming EUS.  The H«S, however, will react almost immediately with the lime.
In this system, the sulfur is transferred from the coal to the lime with an
H~S intermediate.

     The first step in the overall chemical reaction is to release the sulfur
from the coal as H«S.  However, the sulfur in the coal is not a distinct
chemical species, but exists in many forms that react with hydrogen at
varying temperatures.  The H^S can also back-react with the coal, forming
stable coal-sulfur complexes.  The program is designed to test the removal of
sulfur from the coal at varying temperatures, to determine the severity of
treatment required for manufacturing an environmentally satisfactory solid-
fuel product.  The sulfur-getter was included in the system to enhance the
sulfur-removal rate and minimize the back-reaction.

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                                  MATERIALS
COAL

     The coals used in the project, their proximate and ultimate analyses,
and sulfur-by-type analyses are presented in Tables 1 and 2.  Two coals from
the Illinois No.  6 seam are listed.  The first of the Illinois coals was
originally used in the project because it was readily available.  However,
this coal was severely weathered, and sulfur removal proved difficult.  The
second  coal sample was therefore obtained for additional testing.  These coals
provided a wide range of  sulfur content.  Their rank ranged from the low-sulfur
Western coals to  the higher-sulfur-bearing Midwestern and Eastern coals.

     Fluidization characteristics were evaluated on a sample of Illinois No. 6
coal scalped at —10 mesh.  These fluidization tests were made in a 1.5-inch-
diameter Lucite apparatus, utilizing air at ambient temperatures.  The
resulting fluidization curve  is shown in Figure 1.  The apparent minimum
fluidization velocity of  0.03 ft/s is lower than expected and is probably
caused  by the wide range  of particle sizes.  The velocity required for sus-
pending the larger particles  was about 1 ft/s, but they do not greatly
influence the pressure drop across the bed or the apparent minimum fluidization
velocity.  Better fluidization and mixing were expected in the pilot unit
because of the distribution-plate design and the continuous flow of material.

     In the second phase  of the program, after extensive screening by small-
scale thermobalance tests of  all the coals listed, Western Kentucky No. 9
coal was selected as a good sample for complete testing.  Later, a coal from
West Virginia was also examined.  Most Western coals could be eliminated from
testing because their initial sulfur content was low; also, the high oxygen
content of the Western coals  was attacked by the reductant, causing process
inefficiency.  Preliminary treatment was discovered to be necessary to prevent
agglomeration of  the selected coals at the operating conditions of the
proposed system.  The pretreatment conditions were determined for these coals,
as discussed starting on  page 80.

ACCEPTOR

     Limestone (CaCO~) was the original acceptor considered for this program.
The laboratory analysis of Tymochtee limestone, obtained from Huntsville,
Ohio,  is presented in Table 3.  This material was relatively coarse, and
fluidization characteristics  (Figure 2) of both —14 and +14 mesh were evaluated.
The —14 mesh exhibited characteristics similar to the —10 mesh coal, but at
slightly higher velocities.   The +14 mesh material could not be fluidized  at
gas velocities less than 1 ft/s.

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                                         TABLE  1.   RAW COAL ANALYSIS
 Proximate Analysis

     Moisture

     Volatile Matter

     Ash

     Fixed Carbon

         Total

 Ultimate Analysis, (Dry)

     Ash

     Carbon

     Hydrogen

     Sulfur

     Oxygen

     Nitrogen

        Total
111.
No. 6*

3.72
36.1
9.8
50.38
100.00
10.20
69.32
4.76
2.62
11.89
1.21
W. Ky.
No. 9

5.9
33.4
14.8
45.9
100.0
15.68
67.47
4.66
4.06
6.75
1.38
Ind.
No. 5

9.0
34.5
11.9
44.6
100.0
13.10
68.60
4.63
3.92
8.32
1.43
Pittsburgh Mont. N. D.
Seam Subbituminous Lignite
Pa.

wt
1.5
27.6
30.8
40.1
100.0
31.29
56.67
3.81
1.45
5.63
1.15
W. Va.

7.7
33.8
10.8
47.7
100.0
10.91
73.43
4.89
3.01
6.45
1.31

17.6
35.7
3.6
43.1
100.0
4.38
72.42
5.01
0.84
16.36
0.99

24.5
32.0
6.3
37.2
100.0
8.30
64.67
4.17
0.64
21.22
1.00
111.
No. 6 t

5.8
24.8
35.7
33.7
100.0
37.88
49.08
3.38
1.20
7.31
1.15
100.00
100.00
100.00
100.00
100.00
100.00
100.00
100.00
* Weathered coal.
t New sample.

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                                           TABLE 2.  SULFUR IN COAL BY TYPE
Ul
111.
No. 6*

0.00
0.32
0.89
1.79
W. Ky.
No. 9

0.00
0.07
2.30
0.97
Ind.
No. 5

0.07
0.00
2.02
1.24
Pittsburgh
Seam
Pa. W. Va.
i- 07
Wt 7o
0.04 0.05
0.00 0.00
1.08 1.49
0.26 1.37
Mont. Sub-
bituminous

0.00
0.00
0.29
0.37
N.D.
Lignite
0.04
0.00
0.21
0.28
111.
No. 6t

0.00
0.00
1.14
0.04
      Sulfur, By Type

          Sulfide

          Sulfate

          Pyritic

          Organic

              Total              3.00      3.34      3.33      1.38      2.91      0.66      0.53      1.18
      Note:  The total sulfur presented here does not agree with the values presented in Table 1.   The analysis
             of sulfur-by-type uses different laboratory procedures that are more accurate.  Therefore, the total
             sulfur values from this table were used for data analysis.


      * Weathered coal.
      t New sample.

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   20
*.  10
•*—
•v

O  8
 CM

I



c  6
          *

O      O
0.007   0.01

   0.008
                      0.02
                                                                                                DD
0.04   0.06 0.08 0.1          0.2



            AIR VELOCITY,  ft/s
                                                0.4    0.6   0.8  1.0
2.0
                                                                                                A-102-924
                 Figure 1.  Fluidization characteristics of Illinois No. 6 coal, —10  mesh.

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                                            AP/L, in. H20/ft
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                       TABLE 3.  LIMESTONE ANALYSIS

          Proximate Analysis, wt %

             Moisture                                        3-3

          Ultimate Analysis, wt %
             CaO                                            30.5

             MgO  .                                         18-6
             C02                                            42.93
             s                                               0,26

             Acid  Insoluble                                   -7.7

          Screens,  %  retained on
               10                                            29.5

               14                                            16.0

               20                                            16.8

               30                                             6,9

               40                                             5.4

               60                                             5-8 .

               80                                             3.3

              100                                             1.5

              200                                             4.8

              325                                             3.1

              Pan                                             6.9

          Bulk Density, Ib/cu ft                              106.0

          True Density, g/ml at 25°C                           2.717
     The original process concept suggested that a coarse-sized limestone and
finer coal would be desirable because this type of mixture would provide easier
separation after treatment.  A mixture of 3 parts —10 mesh coal and 1 part
+14 mesh limestone was fluldized, with the results shown in Figure 3.  Nearly
quantitative segregation occurred in this test, indicating that separation
was feasible, but that co-fluidization, required for the pilot unit, was poor.
A smaller size consist was required for the limestone.  As a result, ease of
separation was sacrificed for the better mixing required in the pilot unit,
and other separation techniques would require evaluation.

     Later thermodynamic studies indicated that quicklime (CaO) would be a
better acceptor than limestone, because lower temperatures and energy inputs
are theoretically required for both the initial desulfurization reaction and

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VO
                    0.01
                                                                          O
                                                                          D     A O
                                                               D
                                                               O
                                      S
                                                                                  D a a
                                                                                      A
                                                                                             \
                                                                A
                                                                ko
                                                                                               \6
                                                                   S

                                                                  Oi^
0.02
0.04   0.06 0.08 O.I        0.2
             AIR VELOCITY,  ft/s
0.4
0.6   0.8   I
                                                                                                A-II2-998
                                  Figure  3.   Fluidization curve for mixed coal-limestone
                                      (25% +14 mesh limestone and  75% —10 mesh coal).

-------
the acceptor regeneration.   The program was therefore redirected to use quick-
lime as the acceptor.  Since limestone and quicklime are physically similar,
smaller particle lime must be used for adequate mixing.

MIXTURE

     In the first tests, a mixture of 4 parts coal and 1 part lime by weight
was used for the feed.  This ratio was chosen to provide several (approximately
4 to 5) times the stoichiometric lime-sulfur requirement.  Laboratory results
from the first test runs indicated that the lime had hydrated and carbonated
from the coal moisture and handling.  The ratio was changed to 2 parts coal
and 1 part lime for subsequent tests to allow sufficient lime for these experi-
mental side effects and still have excess lime for desulfurization.

     The size consist chosen for the two constituents was based on the
fluidization tests discussed above.  Coal was screened at —104-80 mesh and the
lime at —20+60 mesh.  The fines were removed to prevent excess dust loading
of the exit gas system.
                                     10

-------
                             THERMODYNAMIC STUDY
     A thermodynamlc study of the C-H-S-0-Ca-Fe system was made to a) indicate
the theoretical limitations of the possible reactions, b) aid in selecting
sulfur-getter material and getter/coal ratio, and c) provide an input for the
later kinetic studies.

     Graphs showing the log of the equilibrium constant, K, as a function of
temperature for various system reactions are shown in Figures 4 to 7.  The
data for these graphs were calculated independently by two individuals using
different data sources and calculation techniques.  The results agreed closely
and differed only because of variations of material properties given in
different references.  The accuracy of the calculations is determined by com-
parison of the calculated equilibrium constant with literature values.

     Equilibrium data are not available for the coal-sulfur system as it exists
naturally.  Sulfur exists in coal in many forms (pyrite, sulfide, sulfate,
organic), and the organic coal-sulfur chemistry is complex.

     However, the literature indicates that much of the organic sulfur in the
coal is eliminated more readily than the pyritic sulfur.  An even more
difficult sulfur-removal problem is the final decomposition of the ferrous
sulfide that is formed when iron pyrite is desulfurized.  The decomposition
of the ferrous sulfide, therefore, was selected as the basis for the thermo-
dynamic study.

     Figure 4 presents the free energy calculation for the reaction —

                             FeS + H2 *4 Fe + H2S

This calculated graph agrees well with the experimental data obtained by
Rosenquist (3).  His data, over the range of 932° to 1410°F, may be represented
by-

                                  PH S
                                          "
                                               + 0.179


where T is the temperature expressed as °F.  However, significant variations
in the value of the calculated equilibrium constants can occur, depending on
the literature source for the thermodynamic constants of FeS.  For example,
Rosenquist determined a AF for the formation of FeS at 298 K as -22,700 cal/
g-mol.  Other published values are —

                   Kubaschewski and Evans (2)     —24,500
                   Rossini, et al. (4)            —23,200
                   Clark Q.)                      -24,311
                                      11

-------
          400      600      800      1000——__I200     1400     1600     1800
                                                               A-II2-I05E
Figure  4.   Thermodynamic equilibrium in coal-getter process
            for FeS + CaO and FeS + H- reactions.

-------
 8
26

24

22

20

 18

 16

 14

 12

 10

 8

 6

 4

 2

 0

 -2

 -4
              200
400
600
800     1000
    T,°F
                                                        1200
1400
1600
1800
                                                                           A-II2-I05T
Figure 5.  Thermodynamic  equilibrium in coal-getter process for H-S + CaO reactions.

-------
                                                                                 1800
                                                                             A-II2-I054
Figure 6.   Thermodynamic equilibrium in coal-getter process  for FeS + CaC03 reaction.

-------
                                                                                     1800
                                                                                A-112 -1055
Figure 7.   Thermodynamic equilibrium  in  coal-getter process for CaCO., and  CaS  + H?0 reactions.

-------
 These differences alone can cause log K to vary by 0.5 at 900°F.   In addition,
 heat capacity (C-) data differ from various sources,  and this effect can cause
 additional changes of 0.6 in the value of log K.

      Another thermodynamic problem is the differing choice of standard states
 for sulfur in the literature.   Care must be exercised in the thermodynamic
 calculations of sulfur compounds because of this problem.

      The graph (Figure 4) for the hydrotreatment of FeS indicates that the
 equilibrium partial pressure of H2S is very low, even at elevated temperatures.
 The equilibrium constant, K, for the reaction is equivalent to the ratio of
 the partial pressure of H2S to H-.   Even at elevated  temperatures, the equili-
 brium constant is less than about 10; therefore, the equilibrium partial
 pressure of H0S is low.  Excessive hydrogen recycle rates would be required to
 completely desulfurize even small quantities of pyritic coal if the hydrotreating
 process alone were employed.

      The sulfur-getter concept was based on the results presented in the
 previous paragraph.  The coal could not be economically desulfurized by
 hydrogen alone.  However, if a "sulfur-getter" — a material with a greater
 thermodynamic affinity for sulfur — were introduced into the system, the back
 pressure of the H~S would be reduced and the iron would desulfurize.  Lime-
 stone is an example of this getter:
                           He _i_ PaPH  3^ Pa Q -4- H C\ 4- PPi
                          n O ~ OdVlWrt f^- V^CLO I  flnVJ ~ V^\J«

 As graphed in Figure 7, the reaction should proceed to the right at tempera-
 tures in excess of 800°F.  However, when the generation of H_S is included —

                              FeS + H2 £ H2S + Fe

 gives
 and
                    FeS + H2 + CaC03 <± H20 + C02 + CaS + Fe
                 FeS + H2 + 2CaC03 £ Ca(OH>2 + CaS + Fe + 2CO
 log K values of —2.6 and —6.4 result at 1000°F and are lower at reduced
 temperatures (Figure 6) .

      Reactions  with Ca(OH)2  are more favorable, but those with quicklime —
and
                        FeS  + H2  + CaO «* CaS + HO + Fe
                      FeS + H2  + 2CaO ** Ca(OH>2 + CaS + Fe
are both favorable  in  the  temperature range to be studied (Figure 4).  The
second reaction  is  favored at  temperatures lower than 875°F, indicating that
the required lime addition is  double that expected for simple conversion  to
CaS.  Quicklime  is  therefore a better acceptor than limestone, so quicklime
was used in the  test program.
                                     16

-------
     Regeneration of the CaS was also studied.  Several cases were analyzed
thermodynamically and are shown in Tables 4 through 8 and Figures 8 and 9.

     Case I is regeneration of the CaO and CaS solid mixture with HO.  At
temperatures of 300 to 500 K, all the CaO is converted to Ca(OH)2.  Conversion
of CaS to Ca(OH)2 decreases with the increased temperature.  Table 4 shows the
equilibrium composition of the !CaO:0.3CaS:3H20 system.  At 300 K (80°F) the
operation must be in a vacuum if the water is to remain in the vapor phase;
the maximum total pressure at which water can be in the gaseous phase is 0.5320
psia.  Only 30% of the CaS is converted to Ca(OH)2 at this condition.  Com-
plete CaS conversion to Ca(OH>2 is possible at these temperatures if the oper-
ation is done at higher pressure.  For complete reaction at 212°F, the pressure
should be 15.95 psia, and at 440°F the pressure required is 2584 psia.

     Case II treats the CaO-CaS mix with both H~0 and C02.  In this system,
all the CaO goes to CaC03 between 700 and 1110 K.  At 1300 K, the partial
pressure of C02 must be above 5.0505 atmospheres, to prevent the decomposition
of the CaCOg.  The conversion of CaS decreases with the temperature.  The CO +
S2 formation does not start until the temperature reaches 1100 K.  At 1300 K
the reaction —

                        CaS + C02 -4 CaO + CO + 1/2S

is more favorable, and the conversion of CaS is increased.  The results are
shown in Table 5 and Figure 8.

     Case III, treatment of the CaO and CaS with C0_ only, results in con-
version of all the CaO to CaCO- between 700 and 1100 K.  The conversion of
CaS to CaCOo decreases as the temperature increases from 700 to 1100 K.  The
presence of CO and S2 is not possible in the resulting gaseous phase up to
1100 K.  However, at 1300 K, the reaction —

                        CaS + C02 -> CaO + 1/2S2 + CO

takes place, with the decomposition of CaS to CO and 1/2S2.  This increases
the relative conversion of CaS as the temperature increases from 1100 to
1300 K.  Figure 9 and Table 6 tabulate the data.

     Cases IV and V, treatment with 0- and S02, respectively, were not desirable
because of the formation of CaSO, .  These results are shown in Tables 7 and 8.
Considering these studies, the most favorable one is the first, i.e., regener-
ation with H20 only, because Ca(OH)2 requires lower heat and temperature to
regenerate to CaO than the CaCO» does.
                                      17

-------
                                       TABLE  4.   CASE 1(0.3 MOLE  CaS,  1  MOLE  CaO, 3 MOLES H00)
oo
Temperature
Reaction K Values
   CaO + HZO - Ca(OH)z
   CaS + 2HzO - Ca(OH)j + H2S
Pressure, psia
Composition, mole
   Solid Phase
     Ca(OH)j
     CaS
Liquid Phase
   H20
Gas Phase
   HZO,  mole
   H20,  %
   H2S, mole
   HZS, %
CaS Conversion, %
                                             300 K (80 T)
373 K (212T)
500 K (440 T)


J4.7
1.3
--
1.38929
0.01071
3.452
3.00
96.554
100.00
Very large
1.469
0.5320*
1.092
0.208
--
1.816
95.18
0.092
4.82
30.7
1.
0.
14.7
1.Z8559
0.01441
--
1.4288
83.34
0.28559
16.66
95.20
0016 X 104
23982
15.95* 147.0
1 . 30 1 . 30
—
..
1 . 40 1 . 40
82.35 82.35
0.30 0.30
17.65 17.65
100.00 100.00


14.7
1.00295
0.29705
--
1.9941
99.85
0.00295
0.15
0.98
8.03 X
1.48 X
147
1.0592
0.2408
--
1.8816
96.95
0.0592
3.05
19.73
10J
io-3
1470
1.20745
0.09255
--
1.5851
88.43
0.20745
11.57
69.15


2584
1.3
--
--
1.4
82.35
0.3
17.65
100.00
           Pressure at which all water can remain in vapor phase.
           Pressure above which all CaS can be converted into Ca(OH)2.
                                                                                                                      B-103-1600

-------
                  TABLE 5.   CASE

Temperature
Reaction K Values
   CaO + CO2 -* CaCO3
   CaS + 2CO2 - CaCO3 + COS
   CaS + 2CO2 - CaCO3 + CO + 1/2 S2
   CaS + 2CO2 - CaCO3 + CO + 1 /8 S8
   CaS + H2O + CO2 - CaCO3  + H2S
   CaS + H2O -* CaO + H2S
   CaS + CO2 - CaO + CO + 1 /2 S2
 Pressure, atm
 Composition, mole
   Solid Phase
      CaCO3
      CaO
      CaS
   Gas Phase,  mole
      CO2
      COS
      H2S

      H20
      CO
   Gas Phase,  %
      CO2
      COS
      H2S

      H20
      CO
 CaS Conversion, %
II  (0.3 MOLE CaS, 3  MOLES  H20, 3 MOLES C02> 1 MOLE CaO)

   700  K (800°F)    	900 K (1160°F)	_  .	1100 K (1520°F)
1.
4.
9.
5.

1.













10 X 105
90 X 10"3
80 X 10-6
86 X 10"5
1.3214
64 X 10~5
»
1.3
--
1.7
--
0.3
2.7
36.17

6.38
57.45
100.00

.107.24
3.015 X 10-4
1.982 X 10-5
1. 763 X 10"5
2. 161 X ID"2
2.015 X 10'4
1 10 100
1.02574 1.225834 1.3
0.27426 0.074166
1.97402 1.77321 1.700
0.00024 0.003014 0.0080
0.0255 0.22282 0.2920
2.9745 2.77718 2.7080
39.6847 37.1258 36.1088
0.0048 0.0631 0.1699
0.5126 4.6652 6.2022
59.7979 58.1459 57.191
8.582 75.278 100.00

. 3.020
5.6 X 10~5
3.336 X 10-
1. 563 X 10-
1.748 X 10-
9.96 X 10"*
1 10
1.002148 1.02112
0.297852 0.27888
1.997804 1.97843
0.000048 0.00045
0.002100 0.2067
2.9979 2.97933
39.9732 39.7364
0.0010 0.0090
0.0420 0.4152
59.9838 59.8394
0.716 7.040



5
5
3

100
1.18835
0.11165
1.8078
0.00385
0.18450
2.8155
37. 5713
0.0800
3.8344
58. 5143
62.783
B-103-1601

-------
TABLE 5.   CASE  II (0.3  MOLE  CaS, 3 MOLES H20, 3 MOLES C02>  1 MOLE CaO)  (Continued)
        Temperature
        Reaction K Values
          CaO + CO2 - CaCO3
          CaS + ECOZ - CaCOj + COS
          CaS + 2COZ - CaCOj +• CO•+ 1/2 Sz
          CaS + 2C02 - CaCOj -I- CO + 1 /8 S8
          CaS + HZO + COZ - CaCO3 + HZS
          CaS + H2O - CaO + H2S
          CaS + CO2 - CaO +• CO + 1 /2 Sz
        Pressure, atm
        Composition, mole
          Solid Phase
             CaCO3
             CaO
             CaS
          Gas Phase, mole
             COZ
             COS
             H2S
             Sz
             HZO
             CO
          Gas-Phase, %
             COZ
             COS
             HZS
             Si
             HZO
             CO
        CaS Conversion, %
        1300 K (1880°_F)
          1.98 X 10'1
          4.357 X 10-5
          1.165X 10-*
          1.2406-X 10-6
          7.664 X lO'4
          7.36 X 10-3
          1.1181 X 10-3
                  10
48.9388
49.5102
                100
—
1.073074
0.0226926
2.948845
0.021919
0.025578
2.978081
0.051155
--
1.045474
0.254526
2.976445
0.021919
0.011778
2.978081
0.023555
1.104462

0.195538
1.876596
0.08552
0.009471
2.914480
0.018942
38.2588
0.3638
0.4245
49.4240
0.8489
0.3646
0.1959
49. 5374
0.3918
1.7435
0.1931
59.4184
0.3862
 24.358
 15.158
 34.821
                                                                   B-103-1601

-------
Temperature
TABLE  6.   CASE  III (1 MOLE  CaO, 0.3 MOLE CaS, 3 MOLES C02>

                           700 K  (800°F)                 	900 K (1160T)
Reaction K Value
   CaO + COE - CaCO3
   CaS + 2CO2 - CaCO3 + COS
   CaS + 2CO2 -• CaCO3 + CO + 1 /2S2
   CO + 1/2  S2 -COS
Pressure, atm
Composition
   Solid Phase, mole
     CaCO3
     CaS
     CaO
   Gas Phase, mole
     C02
     COS
     CO
     S2
   Gas Phase, %
     COZ
     COS
     CO
     sz
CaS Conversion, %
Minimum Pressure for 100%
Conversion of CaS, atm




1
1.009714
0.290286
1.980572
0.009714
99.5119
0.4881
3.Z38

1.13 X 105
4.927 X 10'3
9.786 X 10"6
503.6
10 100
1.086016 1.30
0.213984
1.827968 . 1.4
0.086016 0.3
95.5059 82.3529
4.4941 17.6471
28.672 100.00
52.81
107.24
3.0155 X 10--
1.982 X 10"5
15.212
1 10
1.0006 1.01192
0.2994 0.28808
1.9988 1.976164
0.0006 0.011918
99.9700 99.4005
0.0300 0.5995
0.200 3.973
»100

^


100
1.055350
0.24465
1.88930
0.05535
97.1537
2.8463
18.45

                                                                            B-103-1602

-------
                          TABLE 6.   CASE  III  (1 MOLE CaO,  0.3 MOLE CaS,  3 MOLES C00)  (Continued)
             Temperature
1100  K (1520°F)
1300  K (1880°F'
fo
Reaction K Value
CaO + COZ - CaCO3
CaS + ZCO2 - CaCO3 + COS
CaS + 2CO2 - CaCO3 + CO + 1/2S2
CO + 1/2 S, - COS
&
Pressure, atm
Composition
Solid Phase, mole
CaCO3
CaS
CaO
Gas Phase, mole
coz
COS
CO
sz
Gas Phase, %
C02
COS
CO
sz
CaS Conversion, %
Minimum Pressure for 100%

3.049
5.626 X 10-5
3. 3356 X 10~5

1.6867
1 10


1.000113 1.001123
0.299774 0.298877


1.999774 1.997754
0.000113 0.001123



99.9943 99.9438
0.0057 0.0562


0.038 0.370
»>100

o.m
4.357 X :.0"5
1.165 X ,0-4

0.374
100 1 10


1.011066 1.0126
0.288934 0.2595 0.2874
1.0405

1.977868 2.9595 1.9*75
0.011066
0.0405 0.01Z6
0.0202 0.0063

99.4436 97.9902 99.0E80
0.5564
1.3410 0.6473
0.6688 0.3237
3.689 13.5 4.20
»»ioo






100


1.0058
0.2942


1.9884

0.0058
0.0029

99. 5644

0.2904
0.1452
1.93

              Conversion of CaS, atm
                                                                                                        B-103-1602

-------
                                TABLE 7.  CASE IV
OJ
                Temperature
Reaction K Values
   CaO + SO2 - CaSO3
   CaS +2SO2^ CaSO4 + S2
   CaS + 2SO2 -* CaSO4 + 1
   CaS + 2SO2 - CaSO4 + 1
   CaS + 2SO2 -• CaSO4 + 1
   CaS +3/2 SOZ - CaSO3
   CaS + 3/2 SO2 -* CaSO4
   CaS +3/2 SO2 -* CaSO3
   CaS +3/2 SO2
   CaO +3/2 SO2
   CaS + 1/2 SO2
 Pressure, atm
                                  CaSO3
                                  CaSO4
                                  CaO +
12 S4
/3 S6
/4S8
+ 3/4 S2
+ 3/8 S4
+ 1/4 S6
+ 3/16 S8
+ 1/4 S2
3/4 S2
                 Composition
                    Solid Phase, mole
                      CaO
                      CaS
                      CaSO4
                    Gas Phase, mole*
                      S2
                       S02
                 CaS Conversion, %
                                   (0.3 MOLE CaS,  1 MOLE CaO, 3 MOLES  S02>
                                                      900 K (1160°F)
                                          1.3

                                     0.320266 (24.2640)
                                     0.057574 (4.3614)
                                     0.040295 (3.0528)
                                     0.001787 (0.1354)
                                      .0.9000 (68.1859)
                                          100
                    Values in parentheses indicate percent.
  2. 533 X 10-*
       64.021
      60.4395
      90.4383
      55. 5027
 8. 5918 X 10-1
 7.6865 X lO"1
10.3993 X 10'1
 7.2106 X 10'1
   2.99 X 10s
   0.003395
       10
                                       1.3

                                  0.089127 (7.6395)
                                   0.05054 (4.3394)
                                  0.111436 (9.5517)
                                  0.015574 (1.3349)
                                    0.9000 (77.1435)
                                       100
                                                                                                   100
                           1.3

                      0.019105 (1.729)
                      0.024518 (2.219)
                      0.122436 (11.082)
                      0.038739 (3.5061)
                        0.9000 (81.463)
                           100

                           B-103-1603

-------
                           TABLE 7.
                      CASE IV (0.3 MOLE CaS,  1 MOLE CaO, 3 MOLES S02)  (Continued)
N>
JS
                Temperature
                Reaction K Values
                  CaO + SO2 - CaSO3
                  CaS +2SO2- CaSO4 + S2
                  CaS + 2SO2 - CaSO4 + 1 /2 S4
                  CaS + 2SO2 - CaSO4 + 1 /3 S6
                  CaS + 2SO2 - CaSO4 + 1 /4 S8
                  CaS +3/2 SO2 - CaSO3 + 3/4 S2
                  CaS -t- 3/2 SOZ -* CaSO4 + 3/8 S4
                  CaS +3/2 SO2 - CaSO3 + 1 /4 S6
                  CaS +3/2 SO2 -* CaSO3 + 3/16 S8
                                                  1100 K (1520°F)
   CaO +3/2 SO2
   CaS + 1/2 SOZ
Pressure, atm
                                 CaSO4 + 1 /4 S2
                                 CaO + 3/4 S2
               Composition
                  Solid Phase, mole
                     CaO
                     CaS
                     CaSO4
                  Gas Phase, mole*
                     S2
                     S4
                     S6
                     S8
                     S02
               CaS Conversion, %
                                      0.0225
                                      1.2775

                                     0.27505 (22.4893)
                                    0.002925 (0.2392)
                                     0.00005 (0.0041)

                                      0.9450 (77.2674)
                                         100
               "*  Values in parentheses indicate percent.
15.28316
 0.36134
 0.07903
 0.05384
 0.02627
 0.04526
0.014477
0.010855
0.006337
   122.0
 0.00296
      10
                                                                                              100
     1.3

  0.2440 (20.8418)
 0.02425 (2.0714)
0.002475 (0.2114)

    0.90 (76.8754)
     100
   1.3

0.1110 (10.1742)
 0.051 (4.6746)
 0.029 (2.6581)

  0.90 (82.4931)
   100

     B -10 3 -1 60 3

-------
NJ
Ui
                          TABLE 7.
                    Temperatur e
                CASE IV  (0.3  MOLE CaS, I MOLE  CaO,  3 MOLES S02>  (Continued)
Reaction K "Values
   CaO + SO2 - CaSO3
   CaS +2SO2- CaSO4 -I- S2
   CaS + 2SO2 - CaSO4 + 1 /2 S4
   CaS + 2SO2 -> CaSO4 * 1 /3 S6
   CaS + 2SO2 - CaSO4 + 1/4 S8
   CaS + 3/2 SO2 - CaSO3 + 3/4 S2
   CaS + 3/2 SO2 - CaSO4 + 3/8 S4
   CaS +3/2 SO2 -» CaSO3 + 1/4 S6
   CaS + 3/2 SO2 - CaSO3 + 3/16 S8
   CaO + 3/2 SO2 -> CaSO4 + 1 /4 S2
   CaS + 1 /2 SO2 - CaO + 3/4  S2
 Pressure,  atm
 Composition
   Solid Phase, mole
      CaO
      CaS
      CaSO4
   Gas Phase, mole*
      S2
                                                            0.30
                                                             1.0
                                                    1300 K (1800°F)
 0.52234
0.027907
0.002486
0.000931
0.000398
 0.01666
0.002717
 0.00130
0.000688
 0.87496
0.03189
   10
  0.3
  1.0
                                                                                           100
                                                                                           1.3
                                                           0.25(14.2857) 0.25(13.2857)   0.55(37.9310)
                          SO2
                     CaS Conversion,  %
                                        1.5(85.7143)   1.5(85.7143)    0.9(62.0690)
                                        0.0            0.0             100.0
                       Values in parentheses indicate percent.
                                                             B-103-1603

-------
                               TABLE 8.   CASE V (0.3 MOLE CaS, 1 MOLE CaO, 1 MOLE 0  )

   Temperature                     700  K (800°F)      900  K(1160°F)   1100  K(1520°F)   1300  K(1880°F)
   Reaction K Values
      CaS 4- 2O2 -* CaSO4             e51-82              e36'2             e26-31              e19'91
      CaS + 1/2O2 - CaO+ 1/2S2     4.45X106          1.35X105         1.44X104        7.425X103
      CaS -I- 3/202 - CaS03           e38-6o              e"'73             e18'72              e14'32
   Pressure, atm                1    10    100    1    10    100    1    10     100     1     10    100
   Composition
      Solid Phase,  mole
                                	 0.225	   	0.225	    	 0.
10                               	   i.oo	   	  i.oo	    	  i.oo
                                	0.075 	   	0.075	   	 0.075	    	 0.075	
        CaSO3
     Gas Phase, mole
        O2                      	  0	   	  0	   	   0	   	 0 	

   Conclusion:  The only reaction of importance is CaS + 2O2 -» CaSO4.                               A-u-129

-------
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-------
                                                          COS IN THE GAS PHASE,%
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-------
                                   EQUIPMENT
 PILOT  UNIT
      An existing pilot-development unit was renovated  for  use  in  the project.
 The  unit is 10 inches in diameter and about 15 feet  tall.  A 6-inch pipe,
 6  feet  in length,  was used as an inside overflow tube,  so  that the fluidized-
 bed  section is 6 feet in height.  The bottom was redesigned  with  a distributor
 plate that has nonweep nozzles.   Figures 10 through  16  show  the reactor config-
 uration and design in addition to nozzle operating characteristics.

      Material is screw-fed into  the bottom of the reactor  by a variable speed
 drive.   Fluidizing gas (usually  hydrogen)  is introduced below  the distribution
 plate,  flows up through the nozzles,  and fluidizes the  material in the bed.
 When the material reaches the 6-foot  level, it overflows the center pipe and
 falls into one of the receivers, as determined by the position of the diverter
 valve on the overflow line.

      The bed is heated by external electric heaters.  Six  heating zones are
 controlled by, temperature controllers.   The gas flows out  the  top of the
 reactor,  through a cyclone,  a scrubber, and a knockout  drum, and  then out the
 stack.   After the first runs, the cyclone was removed because  tars were con-
 densing in the unit.   The dust loading was small and could be  handled by the
 wet  scrubber.

 BATCH REACTOR

      To gather background data while  the pilot unit was being  renovated, a
 batch reactor was set up.   A flow diagram is shown in Figure 17.  The reactor
 (shown  schematically  in Figure 17) is a 1-1/2 inch stainless-steel pipe with
 a  sintered disk plate for fluidization.  The reactor sits  in a fluidized,
 heated  sand bed.   Preheated air  fluidizes the sand.  Nitrogen  or hydrogen was
 used to fluidize the  material charged to the reactor, with a rotameter for
 flow indication.   A bubbler was  used  to condense tars and  to trap solid parti-
 cles  before the gas was exhausted.

 THERMOBALANCE

      The  thermobalance is  a laboratory device that continuously measures the
weight  of  a sample as it is  being exposed to a controlled  environment of
temperature, pressure,  and surrounding gas composition.  It  has a heated zone
into which the sample can  be lowered  and then heated with  a  controlled time-
temperature profile.   If desired,  rapid heat-up can be  effected by preheating
the unit  to the desired temperature and then lowering the  basket  into the hot
zone.  Gas  flow is large relative to  the coal sample size  so that large changes
                                      29

-------
                                  WATER
             CYCLONE
           (Later Removed
            From System)
              \
  HEATERS
DISTRIBUTION
PLATE
    AIR —flB»
                i
                 VENTURI
                 SCRUBBER
FINES
                                  TAR'
                                  AND
                               WATER
    TREATED
       COAL
        REC
                          -OVERFLOW
                             FEED
                             HOPPER
        SCREW
        FEEDER
                           INSIDE
                           SLEEVE
                          DIVERTER

                          VALVE
  TREATED
  COAL
  REC
                       TO
                      STACK
                                      A7707I723
           Figure 10.  Reactor flow sheet.
                        30

-------
                              .SLEEVE 6-in.
l/8-in.PIPI
NIPPLE!
E
S



— •»

-1

• —

h

^x
r


L
N
f]
^

\
h
-


II
^ —



^^fc__ j

1
f
\
^^
x
_
, —
^^
x^
PIPE
REACTOR SHELL
NOMINAL 10-in.
<*^~ SCHEDULE 60
PIPE
	 	 .._ cetrn CPDIT\A/ H'
rttU bLKLW ȣ_
T 	 |_ STANDARD 10-in.,
1 1 1 U--^i50-psi FLANGE
I ^Xl/4-in. DISTRIBUTION
PLATE
mm
A- 14 -45
Figure 11.   Distribution plate detail.
                31

-------
             2m-
THREE HOLES FOR
      l/4-in. PIPE
COUPLING WELDED
              IN
     l/4-in. PIPE COUPLING
  AT 3 HOLES, WELDED ON
                                               TWELVE I-in. HOLES
                                               EQUALLY SPACED

                                                   6 HOLES EQUALLY SPACED,
                                                   DRILLED TO PASS 1/8-in.
                                                   NOMINAL PIPE, DRILL
                                                   SIZE 7/16-in.
                                                        COLLAR 5-3/4in. OD
                                                        x I in. TALL x l/4-in. THICK
                                                     -3-15/32 in.
                                                    ALL CONSTRUCTION
                                                    304 STAINLESS
                                                    JT
                                                    T
                                                        l/4-in.
l/8-in. HALF COUPLING
AT 6 HOLES, WELDED ON
                                                             D-14-48
                    Figure 12.   Distributor plate.
                                   32

-------
      10-GAUGE
PLATE WELDED
       TO PIPE
                                     3/4-in. 304 STAINLESS-
                                     STEEL PIPE
                                     SCHEDULE 80
                                  2-1/16 in. HOLES
                               — l/8-in, HALF-COUPLING
                                      A-14-49
                Figure 13.  Distributor nozzles.
                             33

-------
o>
X
   O.Ol
   O.lO h
      0.10
    1.0

FLOW,  SCF/min
                                                             10
                                                    A-II2-999
         Figure 14.   Flow of H~ in distributor nozzle.
                               34

-------
                    O.I
                     0.4
0.6  0.8  1.0           2



    VELOCITY,  ft/s



                     A-II2-IOOO
Figure 15.  Distributor plate nozzle pressure drop versus reactor  gas velocity.
                                       35

-------
12 in.
J_
           FRONT VIEW
                                MATERIAL
                                  304 SS [EXCEPT AS NOTED]

                                3- in. NIPPLES
                                  TWO 3-in.SCH 40 NIP'S, I END  N.P.T.;
                                  ONE WITH  1/4 -in. HALF-COUPLING

                                VALVE
                                  HILLS-McCANNA TOP ENTRY 300 psi
                                  SCREWED END, GRAPHITE SEAT,
                                  3-in. BALL VALVE

                                LIFTING PLATE
                                  2 in. x 2 in. x 3/8 in. ft. WITH l/2-in.
                                  HOLE O.C. IN-LINE (VERTICALLY)
                                  WITH  LEG [MILD STEEL]

                                HEADS
                                  TWO 20-in. 0 O.I5-in.-THICK  DISH HEADS
                                  WITH  FLANGES WELDED ON }
                                  ONE WITH l/2-in. HALF-COUPLING

                                RINGS
                                  THREE l/2-in.<|> BAR
SHELL
  20-in.
                                         SCH 5 PIPE, 30 in. LONG
FLANGES
  ONE 3-in.,l50-psi R.F. BLIND FLANGE
  ONE 3-in.,l50-psi SLIP-ON FLANGE
  TWO 6-in.,l50-psi SLIP-ON FLANGE
   WITH BOLTS WELDED AS STUDS;
  ONE 6-in.,l50-psi R.F. BLIND FLANGE
  ONE 6-in,l50-psi R.F. FLANGE WITH
   HOLE FOR 3-in. PIPE

LEGS
  THREE 2 in. x 2 in. x 1/4 in. ANGLE AND
  3-3/4 in. x 4-5/8 in. x 1/4 in. THICK BASEPLATE
  FOR WHEELS WITH  FOUR 3/8-in.$ HOLES
  2-3/4 in. x 3-5/8 in. O.C. (MOUNT LEGS
  120° APART) [MILD STEEL]

WHEELS
  THREE 5Hn.0 SWIVEL CASTERS WITH
  BRAKES

SHACKLE
  3/8-in. SCREW PIN ANCHOR SHACKLE
  [FORGED STEEL]

                        0-14-47
                 Figure  16.   Treated  coal receiver.
                                 36

-------
  N
              -CXJ
             CONTROL
                VALVE
            SHUTOFF
            VALVES
AIR
                 ROTAMETER'
                         T/C
    AIR
PREHEATER
5
A
?
8
                                  FLUID-
                                   IZED
                                  SAND
                                 4T/C
                                                           TO
                                                           FUME
                                                           ELIMI-
                                                           NATOR
                                                  WET
                                                  TEST
                                                  METER
                                             BUBBLER
                                         24 pt
                                          TR
                                                       A-II2-IOOI
         Figure 17.  Batch coal desulfurization equipment.
                              37

-------
in coal composition are associated with very little change in gas qualities.
A flow sheet for the thermobalance test station is shown in Figure 18.

MODIFIED BATCH REACTOR

     The batch reactor used in the first phase of the program was not as
flexible in operation as desired.   For this reason, a new reactor and heating
unit was constructed.

     A diagram of the new type of  reactor is presented in Figure 19.  With
this type of reactor, material charging and discharging was simplified.  The
external heater was designed so that the elements heat the reactor directly.
The elimination of the sand bed reduced the system mass; heat-up was faster
and internal reactor temperatures  were easier to control.  A flow sheet for
the new system is presented in Figure 20.
                                    38

-------
                                                                                       GAS
                                                                                    SAMPLING
                   H2
N2
                                                                                    THERMO-
                                                                                    BALANCE
OJ
vo
                               VENT
                                                     GAS
                                                   SAMPLING
                                          COOLING
                                           H20
                                                                     GAS
                                                                     COOLER
                                                                                             A75I229I8
                                  Figure  18.   Flow diagram of thermobalance system.

-------

l-l/2-in. PIPE
CAPS




•
















































1








•H^
•^^V




i








^^m
^•H




i








^^^•fl




h








^^^^^^^•VHHIPV
••^^•••••••••I^MI
\
\
\
\


1 1

}



\
1


^•••••••••1
•H^M^^MM



i
	 1 1




—



-« 	
NOTE


TUC
                       THERMOCOUPLES
                         l-l/2-in. UNION
                         l-l/2-in SEAMLESS
                              PIPE
                         DISTRIBUTION
                           PLATE
                     NOTE: ALL CONSTRUCTION
                          316 SS
                     THERMOCOUPLE
                                 A-73-1048
Figure 19.  Modified batch reactor.
              40

-------
AIR-

N2-

H2 -
-OO-
-txj-
•OO-
 HIGH AND
 LOW FLOW
ROTAMETERS
                            	f
                                3T/C
            3T/C
     TEMPERATURE
       RECORDER
                     IT/C
                  TEMP.
                  CONT.
                                       SCR
                              I IT/C
                            TEMP.
                            CONT.
                              II
                         220-V POWER
                              II
                             SCR
                                                                 'GAS
                                                                 > SAMPLE
                        0
                        N
                        E
                         I
                        I I

                        Zl

                        8j

                        2!
                                                    EXHAUST
                                                                         WATER
                                                                         QUENCH
                                                                          A75I229I7
                  Figure 20.  Modified batch reactor flow system.

-------
                            LABORATORY PROCEDURES


      Initially,  samples were analyzed by standard ASTM methods.  The coal-
 lime mixture was separated by a float-sink process in carbon tetrachloride,
 and each  fraction was analyzed.

      Total  sulfur was determined by combusting the sample with a flux of
 magnesium oxide  and  sodium carbonate (Eschka reagent).  The S02 generated was
 collected by the flux and, after dissolution, was precipitated as barium
 sulfate.  The  total  sulfur content was then determined gravimetrically.  A
 second sample  was used to determine the sulfur by types.  It was treated with
 HC1, and  the H2S evolved was precipitated as cadmium sulfide.  This I^S is
 assumed to  correspond to the sulfide content of the sample.  The liquid from
 the HC1 treatment contained dissolved sulfate, which was precipitated with
 barium.   The pyritic sulfur was not attacked by HC1 in the first leach, but
 all the nonpyritic iron was removed.  To determine the pyrite content, the
 sulfur was  digested  with concentrated nitric acid for 4 hours and the iron
 content determined titrametrically.  In the standard technique, this iron is
 assumed to  correspond to the pyrite content of the sample.  The organic sulfur
 content was then determined by subtracting the sum of the other sulfur types
 from the  previously  determined total.

      This analytical procedure is a lengthy process and is subject to sampling
 errors.   Several other sources of error were also found:

 a.    The  float-sink  separation in carbon tetrachloride caused iron pyrite
      and  iron  sulfide (properly associated with the coal) to partially
      distribute  in the lime fraction.

 b.    Treated residue samples cannot be ground without significant loss of
      calcium sulfide (caused by hydrolysis with atmospheric moisture).

 c.    Analyses  of lime-pyrite mixtures resulted in apparently low pyritic
      sulfur determinations.  Possibly the nitric acid digestion was
      insufficient for complete removal of this material.

 d.    Calcium sulfate formation from lime in the residue was possible  during
      the  combustion  for total sulfur analysis.  Any calcium sulfate formed
      would not be dissolved in the standard water dissolution of the  flux.

 These  factors and others suggest that the standard ASTM procedures should be
modified  for this work.

     Development of  a new analytical procedure was undertaken, with  emphasis
on several improvements.   Among these were quicker analysis, use of  one sample
for all work,  and reproducibility.  The following procedure resulted.
                                     42

-------
     About 4 to 5 grams of the unground sample is treated in a flask with 6N
HC1.  The l^S evolved flows through three cadmium carbonate traps and is pre-
cipitated as cadmium sulfide.  This is further treated with HC1 and iodine.
Sulfide (S=) is determined titrametrically.

     The treated residue is filtered, giving a filtrate containing sulfate
(S0^~), nonpyritic iron, and calcium  (Ca"*"1").  The residue is air-dried, ground
in a diamonite mortar, and reextracted under reflux with 6N HC1.  This second
extraction removes additional small amounts of the S0.= and nonpyritic iron.
The two filtrates are combined and analyzed.  The iron is precipitated from
the solution as ferric hydroxide, then dissolved and analyzed colorimetrically.
The filtrate, containing S0^=, is acidified, boiled, and barium sulfate pre-
cipitated by the addition of barium chloride.  The precipitate is filtered,
dried, and weighed.  This gives a measure of the acid-soluble sulfate.  The
filtrate is also analyzed for Ca"*""1" by atomic absorption.

     After the second HC1 extraction, the residue is air dried, intimately
mixed with Eschka reagent, and fired  at 800°C for several hours.  The result-
ing mixture contains S0»~ from pyritic and  organic sulfur; this sulfate is
readily extracted in hot water.  The  iron originally present as pyrite appears
as  iron oxide  (Fe^O.,). _The Eschka-water mixture is filtered to separate a
solution containing SO/" from the MgO-Fe_0- residue.  The filtrate is acidified
and boiled; then barium chloride is added to precipitate the S0,=.  Digestion
followed by filtration and drying gives a measure of both pyritic plus organic
sulfur.  Pyritic sulfur is calculated from  the iron in the Eschka residue.
Organic sulfur is determined by the difference of [organic plus pyritic sulfur]
minus pyritic sulfur, as calculated by the  iron analysis.

     Several chemicals were tested by this  procedure.  Reagent-grade zinc
sulfide gave 96% to 98% recovery of theoretical S~.  Technical-grade calcium
sulfide, specified as 80% to 85% CaS, gave  80% recovery of S=, which is good
agreement.  A sample of pure iron pyrite was analyzed.  Ninety-nine percent
of the theoretical iron and 96.4% of  the theoretical sulfur were obtained.
Technical-grade iron sulfide gave 93.7% of  the theoretical sulfide.  NBS-
certified coal (3.02±0.008% sulfur) gave 99.55% of theoretical sulfur by
Eschka.

     Figure 21 presents the revised analytical procedure, which was used to
analyze samples from later tests.
                                     43

-------
                                                       Coal/Lime Sample
                                                           (ung round)
                                                   6N HC1
        HZS GAS
                                                         I HC1 extract |
                                           II
                                        Residue
                                     Air-dry, grind
                                    Reextract in HC1
        I I
     Residue
Pyrites, Organic S
                                                                                                Collect in CdClz,
                                                                                                Na2CO,, and HC1.
                                                                                                Analyze by iodimetry.
 Soluble SO4 ,  Fe,
                                                                                                    Br2,  boil
                                                               I
                                                     Soluble SO4~, Fe, Ca4
r

Air -dry
MgO-Na2CO3 fusion
H2O leaching
1


n i
Residue
Fe203, MgO
Silicates
1
d
LHC
1 1
Silicates

Tl
iLl
1
Fe+++
Leachings
S04=
a) Br2,
HC1, boil
b) Adjust pH
c) BaCl2

II
A i T, BaSO4
Analyze by *
Colorimetric (measure

method
(measure of

pyritic S

,
1
Waste
, solutior
of
pyritic +
organic S)



II
Fe(OH)3
(additional
Br2, boil
NH4OH
|

1 ..
SO4 , Ca4"1"

nonpyritic Fe)
| HC1 |

Analyze by

Adjust pH
Bad;,
	 1, _ ,.,,
i e(C
(nonpyr
[»
)ti)3 £>U4 , ^
£° * e) Adjust
5l| BaCl2
| 1
1

Fe Solution BaSO4
a
PH|

1
^_f
Ca
Analyze by (measure_of Analyze
/-• 1 «^^ A » O -1C, Cf\ "~\ V - —A.— i —
Coloriixietric o 
-------
                         TEST RUNS - START OF PHASE  I
 BATCH REACTOR

      As  previously noted,  the batch reactor  was  used  to  gather preliminary
 data concerning the process while the pilot  unit was  being renovated for use
 in this  program.   A 100-gram charge was  used in  all the  preliminary batch
 tests.   The first  tests used a mix of 4  parts coal to 1  part lime by weight.
 The coal used in these tests was  the initial coal from the Illinois No. 6 seam.
 This ratio corresponds to  about 400% of  the  stoichiometric lime requirement
 if the coal contains 4% sulfur.  Laboratory  analysis  indicated that the lime
 was hydrating (from coal moisture) and carbonating before it could react with
 HpS to give CaS.   Therefore, the  ratio was changed to 2  parts coal and 1 part
 lime for Run 14 and all subsequent tests.  In one test,  iron pyrite and
 calcium  oxide were used as a mixture to  prove the acceptor concept without
 interference from  other coal-related effects.

      In  running a  test, 100 grams of material was charged to the reactor,
 which was then lowered into the fluidized sand bed.   All heaters were turned
 on, and  the reactor was brought to the desired temperature with nitrogen
 fluidizing the sample.  When the  reactor temperature  was reached, hydrogen
 was introduced for a specified time (1/2 hour, 1 hour).  For base-line com-
 parisons, similar  runs were made  using only  nitrogen.  The temperature ranged
 from 600° to 1000°F in 100°F increments.

      After the specified time at  temperature,  the reactor was removed from
 the sand bed.  If  hydrogen had been used in  the  test,  the system was purged
 with nitrogen.  When the reactor  was cool, it was opened, and the sample was
 removed  and submitted to the laboratory  for  analysis.

 PILOT-UNIT TESTS

      Pilot-unit tests were started when  the  modification of the pilot unit was
 completed.   Coal alone was used in the first six tests to determine its oper-
 ating and fluidization characteristics.  After these  tests, a 2 to 1 mixture
 of coal  and lime in the selected  screen  size was used for feed.  The initial
 Illinois No.  6 coal was used in these tests.

      Feed material was mixed and  charged to  the  feed  hopper before the run
was  started.   The  heaters  were turned on, and the controllers were set for the
tun  temperature.   The gas  flow was set to meet the required bed velocity for
fluidization.   The feed screw was turned on  and  the speed adjusted to provide
the  coal  feed rate selected.  The diverter valve, at  the reactor discharge,
was  set  so  that discharged material went into the waste-material receiver.
After the reactor  bed was  filled  and the system  was in steady-state operation,
the diverter  gate  was switched, so that  the  discharged material went to the
second receiver to ensure  a good  sample.

                                      45

-------
      When enough  sample was obtained, the diverter gate was switched back  to
 the waste-material receiver.  If the desired run was complete,  the unit was
 purged with nitrogen and  shut down.  If other conditions were to be checked,
 the controls were changed and the receiver with the good sample exchanged  for
 an empty.  When the new conditions were met and the system was  at steady-state,
 the diverter was  again switched to obtain a sample at the new conditions.
 Several points  can be checked with this technique, and only one heat-up and
 one cleanout are  necessary.  Feed rate and final temperatures were the primary
 parameters varied for the pilot tests.  Samples from all tests  were submitted
 to the analytical laboratory.

 TEST RESULTS -  BATCH UNIT

      Batch tests  were run with the feed types presented above except for Run 20,
 in which FeS2 and CaO were used to test the getter concept.  The test results
 and conditions  are listed in Tables 9 through 12.  The missing  run numbers
 correspond to tests that  were terminated early because of operational problems
 such as off-gas plugs, burned out heater elements, and controller malfunction.

      Table 9 shows the data for the float (treated coal) portions of these
 tests.  The results are presented in ascending temperatures for comparison
 purposes.  Base runs were made with nitrogen to determine the effects of only
 heat on sulfur  removal.   In each set, the hydrogen shows better removal than
 nitrogen except at 700°F.  No tests, however, show enough sulfur removal to
 yield an acceptable product, even at 1000°F and a ratio of 2 parts coal to
 1 part lime.  Problems with material separation prevented complete analysis of
 Runs 18 and 19.

      Data for the sink portions of the tests are shown in Table 10.  The high
 sulfide content of the separated sink fraction shows that pyrite reduction is
 being made.   The  sulfate  content is caused by heavier, mineral  elements of the
 coal reporting  to the sink when separated.  Part of the coal fraction  (or  coal
 tars adsorbed in  the lime) also shows up in the sink portion, as evidenced by
 the carbon values.

      Batch test Run 20 (Table 11) was made with FeS, instead of coal to
 determine the reduction of pyrite to sulfide-type sulfur.  The  results show
 that most of  the  FeS2 was converted by FeS and CaS, as evidenced by the sulfide
 content and by  the increase in nonpyritic iron in the treated sample.  Some
 sulfur was lost during grinding; this was mostly caused by reaction of CaS
 with atmospheric  water vapor, as can be determined by examining the results  of
 the ground and unground samples.

      Table 12 lists the analysis of gas samples taken during some batch test
 runs.   Because only grab  samples could be taken from a continuously-variable,
 batch  situation,  the analyses are not definitive, but give a representation of
 the  distribution  of the gas species.  Evolution of H2S is increased at higher
 temperatures.  The longer-chain molecules containing sulfur are derived  from
 the  thermal decomposition of the coal, as are the carbon-bearing  gases in the
mass spectrometer analysis.
                                      46

-------
TABLE 9.  FLOAT PORTION OF BATCH TESTS
Run No.
Temp, °F
Duration, min
Treatment Gas
Sample
Lab. Ident. No.
Sample Weight, g
Separated Fraction
Weight recovered, g
Proximate Analysis, wt $
Moisture
Ash
Volatile Matter
Fixed Carbon
Ultimate Analysis, wt %
Ash (total dry)
Acid Insoluble
Calcium
Carbon
Hydrogen
Sulfur
Sulfide
Sulfate
Pyritic
Organic
Oxygen (by difference)
Nitrogen
Carbon Dioxide
S as SO2

Raw
Coal




4.5-5.2
10.4-11.0
34. 7-35.4
49. 1-49. 7

10.88-11. 60


6. 71-68.4
4. 66-4. 70
3.05-3.23




11.76-12. 14
1.23-1.25

6. 10-6.46
Heating Value, (S free),Btu/lb 12276
SO2/106 Btu
Type Mix (original)

Ratio by Weight

5.12






10 X 80 M.H.
Coal Lime
20907




3.
9.!
36.
51.

10.


69.
4.
2.

0.
0.
1.
11.
1.

5.




72 0.0
3 89.8
1
38

20 89.81
1.90
66.41
32 0.55
72 1.25
62 0.08

47
64
51
89 7.64
21 0.01
0.66
24
12481
4.




20




1
600
30
H2
Reac
Prod
20654
39.54
Float
30.13

0.9
7.6
34. 7
56.8

7.66


72.2
4.76
1.87
0.0
0.07
0.42
1.38
12.36
1.15

3.74
12920
2.89
Coal/
Lime
4/1

5
600
30
N2
Reac
Prod
20657
46.7
Float
36.06

1.2
8.6
35.8
54. 4

8. 72


71.4
4. 72
2. 49
tr
0. 12
0.46
1.91
11. 50
1.17

4.98
12783
3. 90
Coal/
Lime
4/1

2
700
30
H2
Reac
Prod
20655
49.19
Float
32.01

0. 4
8.2
33.1
58.3

8.20


72. 5
4. 59
2.26
0.02
0. 11
0.24
1.89
11. 18
1.29

4. 52
12875
3.51
Coal/
Lime
4/1

9
700
30
N2
Reac
Prod
20679
56.00
Float
46.7

3.07
9.9



10.21
49.96
9. 75
70. 56
4.84
2.09

0. 14
0. 59
1.36
10.86
1.20
0.24
4.18
12723
3.29
Coal/
Lime
4/1

3
800
30
H2
Reac
Prod
20656
43.36
Float
33.00

0. 7
9.4
24.9
65.0

9. 43


74.0
4. 14
1.90
0.07
0.07
0. 14
1.12
9.27
1.26

3.80
12860
2.95
Coal/
Lime
4/1

10
800
30
N2
Reac
Prod
20680
56. 55
Float
46.2

0. 9
8. 7



8.83
67.7

73. 42
3.99
2.32
0.02
0.07
0. 52
1.71
9.69
1.35
0.40
4. 64
12699
3.65
Coal/
Lime
4/1

14
800
30
H2
Reac
Prod
21156
60. 50
Float
33.85

0.3
9.0
20.2
70. 5

9.03
66.39
5.30
74.94
3. 60
1.99
0. 10
0. 10
0.14
1.65
8.78
1. 44
0.22
3.98
12718
3.13
Coal/
Lime
2/1
B-14-113

-------
                                   TABLE 9.   FLOAT  PORTION OF BATCH TESTS (Continued)
oo
Run No.
Temp, °F
Duration, min
Treatment Gas
Sample
Lab. Ident. No.
Sample Weight, g
Separated Fraction
Weight recovered, g
Proximate Analysis, wt ^
Moisture
Ash
Volatile Matter
Fixed Carbon
Ultimate Analysis, wt %
Ash (total dry)
Acid Insoluble
Calcium
Carbon
Hydrogen
Sulfur
Sulfide
Sulfate
Pyritic
Organic
Oxygen (by difference)
Nitrogen
Carbon Dioxide
S as SO2
Heating Value, (S free),Btu/lb
SO2/106 Btu
Type Mix (original)
Ratio by Weight
12
800
60
N2
Reac
Prod
20736
57. 3
Float
47. 6

0.7
8.4



8.46
65.3

73.50
4.23
2.31
0.01
0. 10
0. 57
1.63
9.84
1.37
0.29
4.62
12834
3.60
Coal/
Lime
4/1
16
1000
30
H2
Reac
Prod
21429
54. 7
Float
30. 6

0. 8
11.4
15.4
72.8

11.47


75.22
3.00
1.67
0. 11
0.08
0.06
1.42
6.65
1.32
0. 67
3.34
12450
2. 68
Coal/
Lime
2/1
18
900
30
H2
Reac
Prod
21743

Float


1.4
9. 1
21.9
67.6

9. 18


74.95
3.88


0.11
0. 22


1.35




Coal/
Lirne
2/1
19
900
30
H2
Reac
Prod
21745

Float


1.2
13.8
13. 7
71.3

14.01


74.24
2.69






1.03




Pretreated
Coal/ Lime
2/1
B-14-113

-------
                                                   TABLE  10.   SINK PORTION  OF  BATCH TESTS
vo
Run No.
Temp, *F
Duration,min
Treatment Gas
Lab Ident. No.
Sample Weight, g         M. H.  Lime
Separated Fraction
Weight Recovered, g
Proximate Analysis, wt 4
     Moisture                 0.0
     Ash                     89.81
Ultimate Analysis, wt £
     Ash (total dry)           89.81
         Acid Insoluble        1,90
         Calcium             66.41
     Carbon                   0.55
     Hydrogen                 1.25
     Sulfur                    0.08
         Sulfide
         SuUate
         Pyritic
         Organic
     Oxygen (by difference)     7. 64
     Nitrogen                 0.01
     Carbon Dioxide           0. 66
     Type Mix (original)

     Ratio by Weight
1
600
30
Hj
20654
39.54
Sink
4.16
0.2




2.52

0.59
0.22
0.31
0.05
0.01



Coal/
Lime
4/1
5
600
30
NZ
20657
46.7
Sink
8.50





3.4
2.49
0.68
0. 16
0.14
0.06
0.32

0. 5

Coal/
Lime
4/1
2
700
30
Hz
20655
49.19
Sink
8.07
0.1




8.49
2.18
1.62
0.27
0.50
0.42
0.43



Coal/
Lime
4/1
9
700
30
Nz
20679
WHVHMHV^V
56.00
• Sink
8.64
0.39
75.36
75.66
4.44
45.5
3.58
2.31
1.42
0.15
0.43
0.46
0.38
14.89
0.06
2.07
Coal/
Lime
4/1
3
800
30
Hz
20656
43.36
Sink
8.44
0.1




12.4
1.96
1.19
0.39
0.48
0.33
0.0

0.2

Coal/
Lime
4/1
10
800
30
NZ
20680
56.55
Sink
10.35
0.3
73.3
73.49
9.00

10.65
1.86
2.70
0.15
0.59
1.96
0.0
8.47
0.18
2.65
Coal/
Lime
4/1
14
800
30
HZ
21156
^^v^^M^*^
60.50
Sink
26.65
0.0
85.3
85.3
3.91
62.4
5.80
0.68
2.03
1.01
0.92
0.09
0.01
2.30
0.10
3.79
Coal/
Lime
2/1
                                                                                                                   B. 14-112

-------
                                            TABLE 10.   SINK PORTION OF BATCH TESTS  (Continued)
Ui
o
Run No.
Temp, °F
Duration,min
Treatment Gas
Lab Ident. No.
Sample Weight, g
Separated Fraction
Weight Recovered, g
Proximate Analysis, wt *
    Moisture
    Ash
Ultimate Analysis, wt $
    Ash (total dry)
        Acid  Insoluble
        Calcium
    Carbon
    Hydrogen
    Sulfur
        Sulfide
        Sulfate
        Pyritic
        Organic
    Oxygen (by difference)
    Nitrogen
    Carbon Dioxide
    Type Mix (original)

    Ratio by Weight
12
800
60
N2
20736
57. 3
Sink
9.7
0.22
71.4
71. 54
12. 74
12.14
1.79
2.90
0.35
0.76
1.73
0.06
8.41
0. 23
2.99
Coal/
Lime
4/1

16
1000
30
H2
21430
54.7
Sink
24. 1
0. 5
82.9
83. 32

1. 60
1.14
0.99
0.30
0. 55
0.09
0.05
10.65
0.06
2.24
Coal/
Lime
2/1

18
900
30
H2
21774

Sink

0.0
86.0
86.07

6.95
1.36






0.09

Coal/
Lime
2/1

19
900
30
H2
21746

Sink

0.0
93.0
93.2

3. 54
0.43






0.01

Pretreated
Coal/Lime
2/1
B-14-112

-------
                  TABLE 11.   BATCH TEST  RUN 20
                              Feed  Unground  Ground
                                            Reactor Material
Lab Ident.No.
Separated Fraction
Proximate Analysis,
    Moisture
    Volatile Matter
    Ash
Ultimate  Analysis, wt
    Ash (Dry)
    Carbon
    Hydrogen
    Sulfur
         Sulfides
         Pyrite s
    Oxygen
    Nitrogen
    Carbon Dioxide
Iron (Nonpyritic)
21227
Total
0.0
0.0
81. 72
81.72
0.0
0.1
6. 78
0.05
5.28
10.77
0.01
0.62
0.65

21227
Total
0.0

89.5
89. 56
0.26
0. 12
5.23
5.17
0.46
4.34
0.05
0.44
4.88

2122?
Total
0.0

85.83
85.83
0.05
0.07
5.06
4.34
0.16
8.43
0.02
0.54
5.13

21327
Sink
0.3

87.6
87.75
0.05
0.10
4.18
3.22
0.17
7.36
0.01
0.55
4.18

21227
Float
0.2

84.0
84.22
0.18
0.37
3.04
2.15
0.06
11.38
0.01
0.80
3.04
A-14-130
         TABLE 12.   BATCH  TEST GAS  SAMPLE  ANALYSIS
    Run No.
    Temperature,  °F
    Chromatograph,  ppm, vol
        Hydrogen  Sulfj.de
        Carbonyl Sulfide
        Ethyl Mercaptan
        Dimethyl Disulfide
        t^Amyl Mercaptan
        Methylethyl  Disulfide
        Methyl Mercaptan
        Thiophene
        Cf, or Higher
    Mass  Spectrometer, mol $
        Nitrogen
        Oxygen
        Hydrogen
        Argon
        Carbon Dioxide
        Methane
        Ethane
        Propane
        n- Butane
        Ethylene
        Propylene
 14
 800
25.3
 6.8
67.6
 0.3
 18
 900
19
900
         0.02
         0.13
         0.03
         0.01
         0.02
         0.01
         0.01
         0.16
20
900
15.0
0.7
11.9
0.3
0.2
1. 1
--
--
	
15.2
1.9
6.3
0. 7
10. 5
--
1.3
2.4
28.5
18.6
0. 5
2.2
0.4
1.0
--
--
0.7
__
63.0
0.9
3.4
--
--
--
--
--
__
        16.3    16.7    24.0
83.5    83.1    76.0
                 0.04
                                                           A-14-131
                                  51

-------
 TEST RESULTS - PILOT UNIT

      The pilot-unit run conditions are listed in Table 13.  The first  six
 tests were made with coal  (no lime) to check the fluidization, gas rates,
 devolatilization,  and general operation at design conditions.  It was  found
 that the coal  should be screened at —10+80 mesh.  The maximum top size was
 selected to promote good fluidization, and the bottom size was selected  to
 minimize the fines in the  exhaust system.  The gas velocity required was about
 3.0 ft/s for satisfactory  mixing and operation.  Data from these runs  and the
 time-temperature matrix are presented in Tables 14 through 25.

      For Runs  7 through 14, the feed mixture was 2 parts coal (—10+80  mesh) to
 1 part lime  (—20+60 mesh).  In Run 15 the same weight ratio was used,  but the
 feed material  size was all —80 mesh screen.  Hydrogen was the fluidizing gas
 in all tests except No. 14; in this test, an attempt was made to add steam
 to the unit.   This attempt was unsuccessful because the wet steam caused a
 large pressure drop across the distributor plates and the run was aborted.
 No further attempts to use steam were made because a change in the reactor con-
 figuration would be necessary.

      In Runs 7 through 9C, material was fed to the unit at 50 Ib/hr resulting
 in a reactor residence time of about 1 hour.  The bed temperatures tested
 ranged from 750° to 1000°F in 50°F increments.  The feed rate was 100  Ib/hr in
 Runs 10 and 11, and the temperatures were 1000° and 900°F.  Runs 12A and 13
 were made at 25 Ib/hr and  1100° and 900°F.  Run 12B was at 200 Ib/hr and 900°F.
 The final run  with the fine material was made at 60 Ib/hr and 900°F.   The time-
 temperature matrix for the pilot-unit runs is presented in Table 19.   Lab
 analyses for Runs  7 through 9C are shown in Tables 20 through 25.

      Run 7 (Tables 20 and  21) illustrates the reduction of the pyritic sulfur
 in the coal at 1000°F.  Sulfide-type sulfur has increased, evidence that the
 FeS2 is being  converted to FeS and CaS is being formed.  In the float-sink
 separation, much of the sulfide-type sulfur is reporting to the sink portion.
 Some of the coal,  or possibly tars absorbed by the lime, is in the sink  fraction,
 causing the high carbon content.  Also, some lime stayed with the float, as
 shown by the higher ash content of the float material as compared with the
 original coal.

      Table 22  shows the analysis for Run 8A.  This run is similar to Run 7 but
 the  temperature was 100°F  lower.  The results are much the same for both runs;
 although the pyritic sulfur has been attacked, the organic sulfur content has
 not  changed appreciably, therefore, the overall sulfur content is still  high.

      Run 8B (Table 23) was made at still a lower temperature, 750°F.   The
 sulfur  reduction was even  less than in the previous runs.  Pyritic  sulfur was
not  reduced as much as in  the other tests so more sulfur remains  in  the
 treated material.

     Pilot runs 9A and 9B  (Table 24) were made at 950° and 850°F, respectively.
These data also show pyrite-sulfur reduction but the organic  sulfur  content of
the  coal is relatively unchanged.  Again, this causes residual  sulfur values
that are higher than the desired values.
                                      52

-------
                    TABLE  13.  PILOT-UNIT RUN CONDITIONS
Run No.  Feed Rate Tb/hr  Temperature, "F     Gas
Material
1
2
3
4
5
6
7
8A
8B
9A
9B
9C
10
11
12A
12B
13
14
15
33
63.5
33. 6
66.7
77.0
50.0
50.0
50.0
50.0
50.0
50.0
50.0
100.0
100.0
25.0
200.0
25.0
50.0
60.0
Ambient
Ambient
600
800
825
850
1000
900
750
950
850
800
1000
900
1100
900
900
900
900
N2 Raw coal
N2 10 X 80 mesh Coal
N2
N2
N2
H2 \
i 10 X
HZ t,20X
H2
H2
H2
H2
H2
H2
H2
H2
H2
H2
H2 '



80 mesh Coal
60 mesh Lime











I Steam 1 —80 mesh Coal
                                                         80 mesh Lime
                                    53

-------
                                            TABLE 14.   SIZE  ANALYSES  OF  PILOT-UNIT TEST  2
Sample
Description


Lab  Ident  No.
Size Consist.
 wt °» retained
 on stated size
   10
   14
   20
   30
   40
   60
   80
  100
  ZOO
  325
  Pan
   Feed I
   Initial
drum of feed
   20883
     2.1
     7.5
    41.3
    18.2
    12.3
    11.7
     4.3
     2.0
     0.4
     0.1
     0.1
   Feed II
   Final
drum of feed
                  20884
    1.1
    3.4
   24.2
   17.6
   16.1
   21.2
   10:4
    4.9
    1.0
    0.0
    0.1

5
1 1 treated coal
,-eiver (bottom)
to 1/1 hr ~>
20HHO
0.5
2.0
18.3
13.6
14.1
20.1
10.4
4.3
5.9
4.0
6.8

^

/3 to 1-1/3 hr
20888
0.7
2.7
22.6
15.5
15.3
10.3
P. 9
3.4
4.5
2.0
3.1
Sample No.
5

-1-1/3 to
2 hr
20887
0.5
2.0
18.1
16.1
16.6
'.4.1
10.9
5.0
4.5
1.3
0.9

2

~2 to
2-2/3 hr
Z0886
0.4
1.2
15.5
14.5
16.2
26.6
13.0
6.0
4.7
1.2
0.7

1
Final treate
in receiv«
~2 2/3 to 3-
20685
0.2
1.0
19.1
20.9
19.2
23.8
8.7
3.9
2.5
0.5
0.2
   Reactor
Reactor » esidue
 at end of test
                                                                                                                  20891
      0.5
      7.6
     61.5
     19.7
      7.6
      2.3
      0.3
      0.2
      0.1
      0.1
      0.1

-------
TABLE 15.   SAMPLE  ANALYSES  FOR RUN 3  (N?, 600  F, WITHOUT LIME)
    Sample                      Feed        Reactor

    Lab Ident  No.               Z0907         20894

    ANALYSIS:

       Proximate, wt %

          Moisture                3.72          0.7
          Volatiles               36.1           32.8
          Ash                     9.8           13.1
          Fixed Carbon           51.38          53.4

       Ultimate, wt %

          Ash (dry)               10.20          13.20
          Carbon                 69.32          68.20
          Hydrogen                4.76          4.36
          Sulfur                   2.62          2.55
          Oxygen                 11.89          10.59
          Nitrogen                1.21          1.10
          Carbon Dioxide          --           	

       Bulk Density.lb/cu ft       48.9           51.3

       Screen,% retained on

           10                     0.0           1.3
           14                     0.6           3.1
           20                    16.4           26.5
           30                    14.6           18.1
           40                    17.0           16.7
           60                    26.4           20.7
           80                    15.5           8.5
          100                     7.1           3.3
          200                     2.1           1.6
          325                     0.1           0.1
          Pan                     0.2           0.1
                        Receiver

                          20893
                           0.7
                          31.2
                          11.0
                          57.1
                          11.03
                          70.3
                           4.26
                           2.64
                          10.58
                           1.19
                           39.3
                          5.2
                         31.7
                         20.0
                         43.1
                         21.14
                         58.20
                          3.67
                          3.39
                         12.66
                          0.94
                                     26.8
0.9
1.7
20.6
18.4
19.8
23.8
8.7
3.0
2.4
0.5
0.2
0.0
0.3
0.3
0.3
0.0
0.3
0.3
0.3
8.3
17.6
72.3
                                                                   A-14-118
TABLE 16.   SAMPLE ANALYSES  FOR RUN 4 (N0,  800°F,  WITHOUT LIME)
     Sample

     Lab Ident No.

     ANALYSIS:

        Proximate,wt %

           Moisture
           Volatiles
           Ash
           Fixed Carbon
Feed
20907
 3.72
36.1
 9.8
51.38
Reactor
 20925
  0.4
 20.1
 17.8
 61.7
           Discharge
Receiver     Tube
  20926
   0.00
  23.1
  14.8
  62.1
                                      20924
 0.6
19.4
 8.7
71.3
        Ultimate, wt /°

           Ash (dry)               10.20          17.89
           Carbon                 69.32          67.35
           Hydrogen                4.76           3.43
           Sulfur                   2.62           2.47
           Oxygen                 11.89           7.60
           Nitrogen                 1.21           1.26
           Carbon Dioxide

        Bulk Density,lb/cu ft       48.9           36.21

        Screen, % retained on
            10                      0.0            2.2
            14                      0.6            8.2
            20                     16.4           40.8
            30                     14.6           21.1
            40                     17.0           13.6
            60                     26.4           10.0
            80                     15.5            2.5
           100                      7.1            0.8
           200                      2.1            0.5
           325                      0.1            0.2
           Pan                      0.2            0.1

                                        55
                            14.81
                            69.60
                             3.79
                             2.39
                             8.14
                             1.27
                           34.4
                           8.77
                          76.12
                           3.58
                           1.77
                           8.27
                           1.49
                                      27.0
1.5
1.8
14.5
17.0
20.7
26.6
10.7
4.1
2.7
0.3
0.1
10.3
9.6
23.4
14.1
13.7
15.8
6.4
2.8
2.6
0.7
0.6
                                                                     A-14-119

-------
              TABLE 17.   PILOT-UNIT  RUN  5  (N0,  825°F)
     ANALYSIS
       Proximate, wt %
          Moisture
          Volatile
          Ash
          Fixed Carbon

       Ultimate, wt %
          Ash (dry)
          Carbon
          Hydrogen
          Sulfur
          Oxygen
          Nitrogen
                         Coal Feed
              3.72
             36.1
              9.8
             51.38
             10.20
             69.32
               .76
               .62
 4.
 2.
11.89
 1.21
          Sulfur/Carbon Ratio 0.0378

        Bulk Density, Ib/cu ft  48. 9
        Screens,
            10
            14
            20
            30
            40
            60
            80
           100
           200
           325
           Pan
                  retained on
              0.0
              0.6
             16.4
             14.6
             17.0
             26.4
             15.5
              7. 1
              2.1
              0.1
              0.2
Reactor
Material
0.5
16.3
13.8
69.4
13.86
72.82
3. 12
2.15
6.63
1.42
0.0295
33.6
0.4
2.8
26.2
20.3
18.2
19.3
7.3
3.0
1.9
0.3
0.3
Coal Receiver
Top Middle Bottom
0.4
22.3
13.6
63.7
13.70
70.49
3.79
2.29
8.48
1.25
0.0325
32.3
3.9
3.1
15.8
13.9
16.5
24.4
12.4
5.5
3.9
0.3
0.3
0.8
19.5
12.5
67.2
12.61
72.61
3.23
1.86
8.29
1.40
0.0258
23.5
1. 1
7.0
33.7
22.2
16.5
13.2
4.0
1.3
0.6
0.2
0.2
0.7
13.4
14.0
71.9
14. 13
75. 10
2.60
2.22
4.96
0.99
0.0296
21.8
6.8
9.4
22.2
16.2
15.2
16.4
7.0
2.8
2.6
0.8
0.6
                                                            A-14-120

TABLE 18.   PILOT-UNIT RUN 6  (N?  AND  H2,  850°F,  50  Ib/hr  COAL)
                           Feed Coal
                          N2
                         Treated
                                                   Treated
                                                              Reactor
    ANALYSIS
Proximate, wt %
Moisture
Volatile
Ash
Fixed Carbon

3.72
36. 1
9.8
51.38

0.5
21.2
14.9
63.4

0.3
18.5
11.5
69.7

0.7
19.3
18.7
61.3
      Ultimate, wt
         Ash (dry)
         Carbon
         Hydrogen
         Sulfur
         Oxygen
         Nitrogen
             10.20
             69.32
              4.76
              2.62
             11.89
              1.21
15.00
69.20
3.31
2.38
8.81
1.30
11.56
73.24
3.42
1.73
8.56
1.49
18.84
66.24
3.06
2.63
7.74
1.31
      Bulk Density,  Ib/cu ft  48.9
      Screens,
         10
         14
         20
         30
         40
         60
         80
       100
       200
       325
       Pan
% retained on
              0.0
              0.6
             16.4
             14.6
             17.0
             26.4
             15. 5
              7. 1
              2. 1
              0. 1
              0.2
                          36.6
              4.0
              1.0
              6.6
              9.3
             15.6
             30.4
             17.6
              8.6
              6.0
              0.6
              0.3
                                                    24.3
 2.8
 6.4
31.8
21.0
16.6
13.7
 4.2
 1.6
 1.5
 0.3
 0. 1
                                                               33.4
 9.1
 7.4
35.7
17.9
12.3
 9.7
 3.0
 1.3
 1.8
 0.8
 1.0
                                    56
                                                             A-14-121

-------
                               TABLE 19.   TIME-TEMPERATURE MATRIX FOR PILOT-UNIT RUNS






                Feed Rate, Ib/hr      	Temperature,  F
Ui
(Residence Time,
min)
25 (120)
50 (60)
100 (30)
200 (15)
750 800 850 900 950
13
8 B 9C 6, 9B 8 A 9A
11
12B
1000

7
10

1100
12A




-------
   TABLE 20.   PILOT-UNIT RUN 7 (H2,  1000°F,  50 Ib/hr MIX)
                                      Receiver
                       Feed	
                       Coal   Tr->    Middle     Bottom    Reactor
ANALYSIS

  Proximate, wt %
    Moisture
    Volatile
    Ash
    Fixed Carbon

  Ultimate, wt %
    Ash (dry)
    Carbon
    Hydrogen
    Sulfur
    Oxygen
    Nitrogen
             3.9    0.0
            37.4   10.1
             9.6   65.9
            49.1   24.0
             9.98
            69.14
             4.46
             3.33
            11.91
             1. 18
65.93
25.63
 1.16
 2. 17
 4.66
 0.45
         0.0
        11.4
        51.3
        37.3
51.31
38.90
 1.63
 2.12
 5.33
 0.71
            0.0
           11.7
           46.7
           41.6
46.77
43. 10
 1.75
 2.70
 4.88
 0.80
           0.0
          10.1
          64.4
          25.5
64.41
27. 13
 1.30
 2.44
 4.25
 0.47
  Bulk Density,  Ib/cu ft 49.3   47.3
  Screens,
    10
    14
    20
    30
    40
    60
    80
   100
   200
   325
   Pan
% retained on
             0.1
             0.6
            14.5
            14.0
            16.0
            26.6
            16.2
             7.9
             3.6
             0.2
             0.3
 0.2
 0.7
 5.1
 7.6
18.2
31. 1
15.4
 6.8
10.2
 3.4
 1.3
                           30.9
 1.7
 9. 1
22.0
14.9
18.5
20.2
 6.5
 2.7
 3.0
 0.9
 0.5
                   29.4
 2.0
13.6
28.1
14.0
15.5
16.2
 4.6
 1.8
 2.8
 0.9
 0.5
                     39.7
 1. 1
 7.6
21.4
12.
22.
23.
,7
 1
,5
 6.0
 1.8
 2.0
 1.0
 0.8
                                                      A-14-122
         TABLE  21.   PILOT-UNIT  RUN  7,  FURTHER  DETAIL
                                         Coal Receiver Top
 Proximate Analysis,  wt %
       Moisture
       Volatile
       Ash
       Fixed Carbon

 Ultimate Analysis, wt %
       Ash (dry)
       Carbon
       Hydrogen
       Sulfur (total)
           Sulfide
           Sulfate
           Pyritic
           Organic
       Oxyg en
       Nitrogen
       COa

 Nonpyritic Iron
                                Total
                      0.0
                     10. 1
                     65.9
                     24.0


                     65.93
                     24.96
                      1. 16
                      1.89
                      0.83
                      0. 17
                      0.06
                      0.83
                      3. 17
                      0.45
                      2.44

                      0.87
                                               Float
                 0.40
                 14.80
                 ,r, 4
                2L.46
                65.63
                 2.77
                 1.83
                 0.22
                 0. 17
                 0. 10
                 1.34
                   . 12
                 i  18
                 I  01

                 i  03
                        Sink


                        0.00

                       77.7
                       77.76
                       11.76
                        0.91
                        1.88
                        1.09
                        0.20
                        0.07
                        0.52
                        4.04
                        0. 17
                        3.48

                        0.78

                   A-14-123
                                 58

-------
TABLE  22.   PILOT-UNIT RUN  8A  (H.
    Proximate Analysis, wt %
         Moisture
         Volatile
         Ash
         Fixed Carbon

    Ultimate  Analysis, wt %
         Ash ( dry)
         Carbon
         Hydrogen
         Sulfur  (total)
             Sulfide
             Sulfate
             Pyritic
             Organic
         Oxygen
         Nitrogen
         CO2
    Bulk Density,  lb/cu ft


    Screens, %  Retained on
         10
         14
         20
         30
         40
         60
         80
         100
         200
         325
        Pan
                              Reactor
                              Material
 0.0
22.2
Z8.4
49.4


28.41
54.60
 3.23
 2. 18
10.57
 1.01


41.3
 0.1
 1.5
31. 3
18.5
17.2
19.8
 6.3
 2.4
 2.2
 0.4
 0. 3
             900°F,  50 Ib/hr MIX)
                    Coal Receiver
Total Float
0.0
11.5
66.6
31.9
66.63
22.86
1.32
1.80 1.92
0.84 0.03
0.26 0.09
0.12 0.21
0.58 1.59
5.97
0.43
2.72
52. 1
0. 1
0.5
3.7
6.4
21. 1
40.7
15. 1
5. 2
5. 2
1. 3
0.7
Sink







1.70
0.85
0. 16
0. 11
0. 58















                                                             A-14-125
TABLE 23.   PILOT-UNIT  RUN 8B  (H2,  750 F,  50  Ib/hr MIX)

                                               Coal Receiver
    Proximate Analysis, wt °
          Moisture
          Volatile
          Ash
          Fixed  Carbon

    Ultimate Analysis, wt %
          Ash (dry)
          Carbon
          Hydrogen
          Sulfur (total)
              Sulfide
              Sulfate
              Pyritic
              Organic
          Oxygen
          Nitrogen
          CO2
    Bulk Density, lb/cu ft
     Screens,
          10
          14
          20
          30
          40
          60
          80
         100
         200
         325
         Pan
             % retained on
Total Float
0.0
19.7
47.8
32.5
47.81
36.56
2.35
2.08 2.11
0.64 0.05
0. 24 0. 15
0. 20 0. 34
1.00 1.57
8.55
0.66
1.99
54.4
0.0
0.1
2.6
4.6
13.9
36.6
19.5
9.3
9.6
2.3
1.5
Sink







2.05
1. 31
0.31
0.24
0. 19















                                                           A-14-126
                                   59

-------
TABLE 24.  PILOT-UNIT RUNS 9A AND 9B (H2> 950° AND 850°F, 50 Ib/hr MIX)
Run 9A

Proximate Analysis, wt %
Moisture
Volatile
Ash
Fixed Carbon
Ultimate Analysis, wt %
Ash (dry)
Carbon
Hydrogen
Sulfur (total)
Sulfide
Sulfate
Pyritic
Organic
Oxygen
Nitrogen
C02
Bulk Density, Ib/cu ft
Screens, % retained on
10
14
20
30
40
60
80
100
200
325
Pan
Total

0.0
10.6
68.5
20.9

68.49
23.93
1.29
1.91
1.00
0. 28
0.08
0.55
1.03
0.43
2.92
50.9

0.5
0. 3
1.4
4.0
18.9
44. 1
17.6
5.9
5.4
1.4
0.5
Float

0.9
15.7
16.8
66.6

17.00
67.44
2.83
1.95
0. 14
0. 20
0. 15
1,46
8.56
1.26
0.96













Sink Total

0.00 0.0
12. 1
81.00 60.7
27.2

81.04 60.73
6.45 28.95
0.80 1.55
1.80 1.58
1. 22
0. 27
0. 10
0. 21
6.29 4.69
0. 11 0.48
3.51 2.02
43.9

0. 3
0.9
3.8
8.4
25. 5
39.8
13.0
4.2
3. 1
0.6
0.4
Run 9B
Float Sink

1. 1
18.6
14.7
65.6

14.91
68. 16
3.20
1.92
0. 16
0. 15
0. 19
1.42
9.38
1. 17
1.26














0.00

84.5


84.49
4.39
0.90
1.31
0.79
0.33
0. 11
0.08
5.65
0.08
3. 18













A-14-124
TABLE 25. PILOT-UNIT

Proximate Analysis, wt ^
Moisture
Volatile
Ash
Fixed Carbon
Ultimate Analysis, wt ^
Ash (dry)
Carbon
Hydrogen
Sulfur (total)
Oxygen
Nitrogen
C02
Bulk Density, Ib/cuft
Screens, % retained on
10
14
20
30
40
60
80
100
200
325
Pan
RUN 9C



























/TT
\nirj J
Total

0.0
17.3
44.4
38.3

44.44
41.01
2.29
2.09
7.23
0. 68
2.26
45.3

0.1
0.2
0.8
3.6
15.8
39.0
20.8
8.8
8.5
1.6
0.8
800°F, 50
Float

1.0
21.6
10.6
66.8

10.74
72.22
3.69
1.98
9.31
1.39
0.67













Ib/hr
Sink

0.0
..
83.6
__

83.61
4.88
0. 58
2.18
4.78
0.09
3.88












A t A 11
MIX)


























i *
                                   60

-------
     Run 9C (Table 25) at 800°F resulted  in performance similar to the pre-
vious runs.

ANALYSIS OF TEST RESULTS

     Figures 22 and 23 present the pyritic sulfur and organic sulfur contents
of the samples at different  temperatures.  Both batch and pilot-unit tests
caused the pyritic sulfur content to  decrease as the temperature increased.
However, in these tests the  organic sulfur was not reduced enough to achieve
the final content desired.   Because the rate of organic sulfur removal was not
faster than the devolatilization rate, the fraction of organic sulfur in the
remaining treated coal was nearly constant.

CONCLUSIONS

     Data from both the batch and pilot units indicated that, although some
sulfur was being removed and the getter concept was viable,  the degree of
sulfur removal was insufficient.  Sulfur  reduction to values below 1% is
necessary for the treated product to  meet the Federal standards for S02
emission.

     After a review of kinetic data  (next section), it was decided to redirect
the program to acquire more  basic data on smaller-scale equipment.
                                       61

-------


3?
— ^ *»
L£. 1
=> <
i O
— * {J
W Q
LJ
0 H
|S
IP
Q_ ~
Z



0.5
0.45
0.40^
0.35

0.30

0.25
0.20
0.15

0.10

0.05
n

P O PILOT TESTS
L A BATCH TESTS
_ _

—

A
0 °
A A 0

0
A
bi
till
     600
700
                           800         900
                           TEMPERATURE, °F
                                                     1000
                                               MOO
                                                             A-63-809
       Figure  22.  Percent pyritic sulfur in treated coal.
2.0
 1.5

0.5
                             1
                   O PILOT TEST TOTAL  SULFUR
                   • BATCH TEST TOTAL SULFUR
                   A PILOT TEST ORGANIC SULFUR
                   A BATCH TEST ORGANIC SULFUR
                         I             i
600
               700
 800          900
TEMPERATURE,  °F
                                    1000
1100
                                                           A-63-810
   Figure 23.   Percent  total  and  organic  sulfur  in  treated  coal.
                                62

-------
                        KINETIC STUDIES OF OUTSIDE DATA


     The  studies of Vestal and Johnston (1969)  (6) indicate  that much of the
 organic sulfur should be removed prior to pyrite decomposition.  They confirm
 the work  of  Snow (1932) (5) that slow heat-up rates provide  better  sulfur
 release than fast heat-up.  They also indicate that sulfur can be fixed into
 the carbon lattice in a reverse reaction.  The configuration of the fluidized-
 bed reactor  employed in this program caused rapid (about  100°-500°F/s) heat-up
 from ambient to bed temperatures.  These factors suggested that greater sulfur
 removals  might be possible if the reactor configuration permitted slow heat-up
 and inhibited back-reaction.  Therefore, a kinetic analysis  of the  data of
 Vestal and Johnston was made to determine potential sulfur removal  made possible
 by this technique.

     A short computer program was prepared to study the expected reactor
 operation based on the kinetic parameters reported by Vestal and Johnston (6) .
 For the first studies, the assumption was made that these kinetics  applied to
 the rapid heat-up in the pilot-unit, fluidized-bed reactor.   A completely back-
 mixed reactor (a theoretically perfect fluidized bed) was assumed for the
 reactions; hydrogen and coal feed rates were similar to those used  in the pilot-
 unit program.   Temperature, residence time, and lime-to-coal ratio  were the
 major parameters varied in this calculational program.  Figures 24  through
 28 illustrate the results.

     Figure  24 shows the expected amount of pyritic sulfur remaining as a
 function  of  temperature and reaction time.   Because the calculations assumed
 that there can be no back-reaction with hydrogen sulfide  to  remanufacture iron
 pyrite, pyrite removal should be independent of lime content.  Significant
 pyrite removal should be achieved at 900° to 950°F with sufficient  reaction
 time.  These results confirm the ability to decompose pyrite in the pilot unit.

     Figure  25 presents the expected removal of nonfixed  organic sulfur as a
 function  of  temperature and reaction time.   This graph assumes no back-reaction
 of sulfur.   It illustrates that the amount  of available organic sulfur remain-
 ing in the coal will be quite low at 850°F  and  a 30- to 60-minute reaction
 time.  The kinetics  do provide a mechanism for  fixation of the available
 sulfur by a  reaction of the coal char with  H2S.  Figure 26 illustrates this
 effect.   With  large  lime additions,  the amount  of sulfur  fixation is negligible.
 This can  be  seen by  comparing the data in Figure 25 (5-minute reaction time)
with the  largest lime addition of Figure 26.  As lime addition is decreased,
a significant  portion of the previously available sulfur  becomes fixed into
 the coal.   Figure 27 illustrates sulfur fixation at various  reaction times
with stoichiometric  excess-lime-addition rates, and Figure 28 illustrates the
fixation  with  insufficient lime content.
                                      63

-------
 1.0
REACTION
 TIME.mln'
                    800               900

                       TEMPERATURE,"F
      1000

  A-63-947
       Figure 24.  Removal of pyritic  sulfur.
0.0
 700                 800                 900                1000

                        TEMPERATURE,°F                A-63-948

    Figure 25.  Removal of nonfixed  organic sulfur.
                          64

-------
                        800               900
                           TEMPERATURE, °F
    1000

A-63-949
Figure  26.   Fixation of available organic sulfur as a function
             of temperature and lime content.
                         800               900

                             TEMPERATURE,°F
        1000

    A-63-950
Figure 27.   Fixation of organic sulfur with excess CaO present,
                                65

-------
       1.0
      o.s
  "
       0.4
  oo
  
-------
     These graphs assume that the kinetic parameters reported by Vestal and
Johnston (6) are applicable for the fast heat-up rate and isothermal bed
characteristics of our pilot-unit reactor.  The work in the initial program
phase has confirmed their high fraction of pyritic sulfur removal, but the
organic sulfur removal does not agree.  Either the high heat-up rates fixed
the organic sulfur and thus the kinetics did not apply, or the primary coal
sample had a high percentage of previously fixed organic sulfur.

     The calculational program was modified and evaluated for slow heat-up
rates as opposed to the fast rates calculated above for fluidized-bed studies.
Figures 29 and 30 present the mole fractions of the various sulfur constituents
of the coal as the coal is heated in the presence of hydrogen at a rate of
9°F/min.  In Figure 29, representing coal treatment without lime, one type of
available organic sulfur is significantly removed at a temperature of 750°F;
another, at 870 F.  The hydrogen sulfide concentration of the gas at these
temperatures is several thousand parts per million; therefore, some sulfur is
being refixed into the coal.

     The pyrites do not show significant decomposition at 900°F, confirming
the observations made in this preliminary thermobalance work (discussed in the
next section).  Similarly, the iron sulfide formation is not yet high.

     In Figure 30 the system was recalculated with large lime additions.
Decomposition of the available organic sulfurs and pyrites must, of course, be
similar to that in Figure 29 because no mechanism is given for back-reactions.
Hydrogen sulfide concentration decreases because of the calcium sulfide
formation.  Consequently, the formation of fixed sulfur in the coal is reduced.
The fixed sulfur appears to be decreasing at higher temperatures even before
the iron sulfide is significantly decomposed.

     The relative temperatures of fixed sulfur and iron sulfide decomposition
shown in Figure 30 appear to contradict the original data in the Vestal and
Johnston report (6) .  This may be due to the effect of lime on the decomposition
of fixed sulfur or may be caused by the high sensitivity of the kinetic rate
expressions to temperature.  A slight error in the calculation of the decom-
position rate or the initial presentation of the kinetic-rate data will have a
significant effect on the resultant figures.
                                      67

-------
                                       LIME-FREE
     10-2
     10-3
  S 10-4
  o
  E
 (T
 I-

 UJ
 O


 I
ID'5
    IO'6
    10-7
       400       500      600       700       800

                            TEMPERATURE, °F
                                                   900
1000
                                                          A-73-1050
Figure 29-  Coal sulfur fractions heated without lime in the presence  of
            hydrogen.
                                  68

-------
  c
  o
  S  10"* -
 o
 E
 Z
 LU
 O
 Z
 o
 o
                            HIGH LIME ADDITION
       400       500      600       700      800

                              TEMPERATURE, °F
900
1000
                                                         A-73-IO5I
Figure 30.  Coal sulfur fractions heated with high lime additions in

            the presence of hydrogen.
                                  69

-------
            PROGRAM REDIRECTION - END  OF PHASE  I, START OF PHASE II


      Considering the results  from batch tests, pilot tests, and the kinetic
 studies,  a change in the program was  desirable.  Two basic factors could have
 caused the discrepancy between the  initial  sulfur removal results and that
 reported  by other investigators:

 1.    The  primary coal sample,  chosen  for availability and substantial cost
      saving,  was highly weathered.  This weathering may have fixed some
      of the sulfur into the carbon  lattice  of  the coal, making removal
      difficult.

 2.    The  configuration of the  pilot-unit reactor, with nearly instantaneous
      heat-up,  may cause sulfur fixation.

 Consequently,  the program was  redirected to evaluate these effects.

      A thermobalance was used  for initial testing.  One was available for pre-
 liminary  testwork with the initial  coal sample.  These tests were run with the
 thermobalance at a 10°F/min heat-up rate to 900°F and 10 SCF/hr hydrogen flow.
 In  each test,  1.8 grams of solid  material was  charged and the feed was screened
 to  —10+20 mesh,  a size governed by  the mechanical requirements of the equipment.

      The  first test was operated  with coal  only, to obtain reference data on
 devolatilization and desulfurization  of the coal in a hydrogen atmosphere.
 The second test  used the standard coal-to-lime weight ratio of 2:1.  However,
 the coal  and  lime contact was  not good because there was no movement or mixing
 as  in a fluidized-bed system.  The  third test  was operated with a coal-to-lime
 ratio of  1:2  to  increase the  contact  of the coal with the lime particles.

      Laboratory  analyses of the  samples are presented in Tables 26 and 27.
 The total sulfur contents of  the  three feed samples were essentially identical,
 from 3.03% to  3.12%,  when based  on  coal weight.  This is a slightly higher
 percentage of  sulfur than was  shown in other tests, but the percentage may be
 consistent with  the screen size  fraction used  (the larger particles appear  to
 contain a greater fraction of  sulfur).

      In the first test the devolatilization was 25% and sulfur reduction was
 45%  of  the original sulfur in  the coal.  Thirty-five percent  of the organic
 sulfur  was removed,  and 53% of the  pyritic  sulfur decomposed.

      The  total sulfur  loss to  the gases decreased as lime was added,  indicating
 sulfur  recovery  by  the lime.   In  Test 3, for example, nearly  all  of  the  sulfur
 in the  coal was  recovered in the  lime-coal  residue.  Also, because of  volatile
 sorption  into  the lime pore structure, the  devolatilization  losses in Tests 2
and 3 were only  about  21% of the  original coal weight.  In Test  2,  the
                                      70

-------
Test No.

Coal/Lime Ratio

Sample

Lab Ident. No.

Sulfur Composition, wt %
   Sulfide
   Sulfate
   Pyritic
   Organic
      Total
Weight, g
   Initial Sample
   Treated Sample
Weight Loss, %
TABLE 26.   BASIC DATA - THERMOBALANCE RUNS

           CTB-1                 CTB-2
         No lime

     Feed      Residue
     21910
21911
                  2:1

           Feed      Residue
21917
21918
0.00
0.36
1.06
1.69
3.11
0.05
0.10
0.66
1.47
2.28
1 .8440
1.3839
24.95
0.00
0.27
0.90
0.85
2.02
0.21
0.22
0.50
0.70
T~58~
1.9668
1.6881
14.17
                                       CTB-3
                              1:2

                       Feed     Residue
21932
21933
0.00
0.15
0.41
0.48
1.04
0.16
0.19
0 36
0.31
1.02
2.1070
1.9585
7.05
                                                                                       A-14-127

-------
                                 TABLE 27.  THERMOBALANCE RUNS - REDUCED DATA
Test No.
CTB-?
CTB-2
CTB-3
Stream
Feed
Weight Loss,
fraction of coal
Residue
24.95
Sulfur Weight,
based on 100 -Ib
Sulfide
Sulfate
Pyritic
Organic
Total
coal
0.0
0.36
1.06
1.69
3.11
feed, Ib
0.038
0.075
0.49
1.10
1.71

Sulfur
Removal,
%
—
79.2
53.3
34.7
45.0
Feed

Sulfur
based
coal
0.0
0.405
1.35
1.27
3.03
Residue
21.25
Weight,
on 100 -Ib
feed, ib
0.27
0.28
0.64
0.97
2.16

Sulfur
Removal,
%
--
30.0
53.3
24.0
28.7
Feed

Sulfur
based
coal
0.0
0.45
1.23
1.44
3.12
Residue
21.15
Weight,
on 100 -Ib
feed, Ib
0.45
0.529
1.00
0.86
2.84

Sulfur
Removal,
%
--
(17.7)
26.2
40.0
8.9
                                                                                              A-14-128

-------
percentage of pyrite reduction was  similar  to  that  of Test 1, but more organic
sulfur remained in the residue.   This might also  be attributed to the sorption
of volatile matter.  Test  3, however, showed improved organic-sulfur removal
and decreased pyritic removal.

     Significant  sulfur  removal  was achieved in these tests, as evidenced by
the 45% reduction in Test  1  and  the calcium sulfide manufactured in the other
two tests.  However, when  devolatilization  of  the coal  is considered, the net
sulfur content of the treated  coal  calculates  to  about  2%.  Removal of pyritic
sulfur is not so  great as  in the pilot-unit tests because the sample was not
maintained at the high temperature  for  an extended  time.
                                       73

-------
                     SELECTION  OF  COAL  FOR EXTENSIVE STUDY


      The promising results  from the  three tests discussed above indicated that
 further thermobalance work  was justified.  Another unit was rebuilt for
 application in this work because  the one used for the initial test was not
 available for extensive use.

      The first runs in the  rebuilt unit were made with the original, weathered
 Illinois No.  6 coal on hand.   Four tests were made for unit shakedown and to
 establish operating procedures.   Table 28 presents the data from the laboratory
 analyses for Runs  TB-5 to TB-10.  These were all made with a 2:1 coal-lime
 mixture, heated at 5°F/min  to  terminal temperatures of 700° to 1000°F.  All
 tests were made with hydrogen  except Run TB-5, which was made with nitrogen.
 A comparison of TB-5 with TB-8 shows the benefits of hydrogen usage at 900°F.
 The data indicate  that as the  temperature increased to 900 F the sulfur
 decreased.

      Examination of the reduced data,  calculated on a basis of 150 pounds of
 feed, (100 pounds  of coal,  50  pounds of lime) shows formation of calcium
 sulfide.  The calcium sulfide  formation is proved because the amount of sulfur
 as sulfide is greater than  the amount  that would appear as ferrous sulfide
 from pyrite decomposition.  Also, there is less sulfur in the residue than in
 the feed,  indicating a loss (probably  as H^S) from the system, possibly because
 of relatively poor contact  with lime and hydrogen sulfide.  In the tests after
 TB-10,  when lime was used,  the ratio was changed to a 1:2 coal-lime mixture  to
 improve the contact.

      The next test series,  TB-11  to  TB-21, shown in Table 29, was performed  on
 several new coal samples to select one sample for exhaustive testing.  All the
 tests were  run with the new 1:2 coal-lime mixture and were hydrogen-treated.
 They were  heated at 5°F/min to 900°F,  except TB-18  (800°F) and TB-20  (1450°F).
 Tests TB-19 and TB-20 were  not held  at the terminal temperatures, while the
 rest were held at  the terminal temperature for 30 minutes.

      Laboratory data and the values  calculated in Table 29 were used  for
 selection of  the coal for further testing.  Two lower rank coals, Montana  sub-
 bituminous  and North Dakota lignite, were excluded because their  initial  sulfur
 content  was too low to respond to treatment.  Similarly, the samples  of
 Pittsburgh  seam (Pennsylvania  mine)  and Illinois No. 6 were  sufficiently  low
 in  original sulfur content  that they would require less intense  thermal  expo-
 sure for sufficient sulfur  release.  Of the three coal samples remaining,  the
Western  Kentucky No.  9 (an  abundant  Midwestern type) had the highest  sulfur
 content  and the highest after  treatment, indicating that this  coal  would
require  the most extreme treatment conditions.  These conditions, when deter-
mined, should  be sufficient for the  other coal materials available  for initial
                                      74

-------
                                           TABLE 28.   THERMOBALANCE  RUN DATA  (ILLINOIS  NO.
Ui
Run No.
Coal Type
Heating Rate, ° F/min
Terminal Temperature, °
Holding Time, min
Lab Analysis, wt %
   HjO
   Volatile Matter
   Sulfur, wt %, as
      Sulfide
      Sulfate
      Pyritlc
      Organic
         Total
 Weight, g
    Initial
    Treated
 Weight Loss, %
    Of Total Weight
    Of Coal Weight
 Reduced Data
    (100 Ib Coal in Feed)
    Weight,  Ib
    Sulfur Weight, Ib,  as
       Sulfide
       Sulfate
       Pyritic
       Organic
          Total
 Sulfur Content, wt %, as
    Sulfide
    Sulfate
    Pyritic
    Organic
       Total

 * Weathered coal.
                                           Coal
                                            0.00
                                            0. 32
                                            0.89
                                            1.79
                                            3.00
                                          100.00

                                            0.00
                                            0. 32
                                            0.89
                                            1.79
                                            3.00

                                            0.00
                                            0. 32
                                            0.89
                                                   Feed mixture
 0.00
 0.21
 0.60
 1. 20
 2.01
150.00

  0.00
  0. 32
  0. 89
  1.79
  3.00

  0.00
  0. 32
  0. 89
                                            3.00
                                                        3. 00
                                                                        TB-5

                                                                          5
                                                                         900
                                                                          0
                                                                      Residue
  0.06
  0.08
  0. 73
  1. 09
  1.96

4.6162
4.0075

 13. 18
 19. 78
130. 23

  0.08
  0. 10
  0. 95
  1.42
  2. 55
  1. 18
  1.77
  2. 95
                                TB-6
                              	  Illinois No. 6*
                                  5
                                 700
                                  0
                               Residue
  0. 05
  0. 12
  0.41
  1.09
  1.67

4. 5115
4. 3042

  4.59
  6.89
143. 12

  0.07
  0.17
  0. 59
  1.56
  2.39
  0.63
  1.68
  2. 31
SOIS NO.
TB-7

5
800
0
Residue
0.30
0. 10
0. 27
Q. 98
1.65
4. 2482
3.7937
10.70
16.08
133.95
0.40
0.13
0.36
1.31
2. 20
0.43
1. 56
1. 99

6 COAL)
TB-8

5
900
0
Residue
0. 50
0. 10
0. 16
0.82 '
1.58
4. 3311
3.6153
16.53
24.79
125.21
0.63
0.13
0. 20
1.03
1.99
0. 27
1.37
1.64

TB-9

5
1000
0
Residue
0.72
0.07
0.20
0.81
1.80
4.1620
3.4312
17.56
26.34
123.66
0.89
0.09
0.25
1.00
2.23
0.34
1. 36
1.70

TB-10

5
800
0
Residue
0.34
0.10
0. 20
0.97
1.61
4. 2689
3. 9038
8.55
12.83
137.18
0.47
0.14
0.27
1.33
2.21
0. 31
1.53
1.84
B75123042

-------
                                             TABLE  29.    THERMOBALANCE  RUN DATA - VARIOUS COALS
ON
Run No.
Coat Type
Heating Rate, "F/min
Terminal Temperature,
Holding Time,  min

Lab Analysis, wt %
   H20
   Volatile Matter
   Sulfur, wt %, as
      Sulfide
      Sutfate
      Pyritic
      Organic
         Total

Weight, g
   Initial
   Treated
Weight Loss, %
   Of Total Weight
   Of Coal Weight
                 Reduced Data
                    (100 Ib Coal Originally)
                    Weight, Ib                  100.00
                    Sulfur Weight, Ib, as
                      Sulfide
                      Sulfate
                      Pyritic
                      Organic
                         Total
TB-11
W.



Coal
5. 9
33.4
0.00
0.07
2. 30
0.97
3. 34
Kentucky
5
900
30
Mixture


0.00
0.02
0.77
0.32
1. 11
No. 9



Residue


0. 54
0.04
0. 11
0. 38
1.07
                                                                                         TB-12
                                                                                                                          TB-13
                                                          5.0333
                                       300.00
 4.4302

11.98
35.95
                                                  264.06
                                                                               Coal
                                                                               9To~
                                                                              34. 5

                                                                               0.00
                                                                               0.07
                                                                               2.02
                                                                               1. 24
                                                                               3. 33
                                                            100.00
                                                                                      Indiana No.  5
                                                                                             5
                                                                                          900
                                                                                            30

                                                                                        Mixture
                      0. 00
                       .02
                                                                                          4.0500
                                                                       300.00
                                                                                                    Residue
 0.21
 0. 16
 0. 16
 0.29
 0.82
 3. 5607

12.08
36.2-1
                                                                                  263.76
                                                Pittsburgh Seam (Pa.
 Coal
 lT5~~
27.6

 0.00
 0.04
 1.08
 0.26
 1. 38
                                                                                              100.00
                                                       900
                                                        30

                                                      Mixture
                                                                                                                           4.3800
                                                                                                         300. 00
                                                                                                                                      Residue
0. 11
0.0-1
0. 14
0.06
0. 35
                        3.9937

                        8. 82
                       26.46
                                                                                                                    273. 54
0.00
0.07
2.30
0.97
3. 34
0.00
0.07
2. 30
0.97
3. 34
1.43
0. 11
0.29
1.00
2.83
0.00
0.07
2.02
1.24
3. 33
0. 00
D.07
2.02
1.24
3. 33
0. 55
0. 42
0. 42
0.76
2. 15
0.00
0.04
1.08
0.26
I. 38
0. 00
0.04
1.08
0.26
1. 38
0. 30
0. 11
0. 38
0. 16
0.95
                   Sulfur Content, wt %,  as
                      Sulfide
                      Sulfate
                      Pyritic
                      Organic
                         Total

                   Wt % Original Sulfur Removed
                      From Feed
0.00
0.07
2. 30
0.97
3. 34
0.00
0.02
0.77
0. 32
1.11


0.45
1. 56
2.01
0.00
0.07
2.02
1.24
3. 33
0.00
0.02
0.67
0.41
1. 10


0. 65
1. 19
1.84
0.00
0.04
1.08
0. 26
1.38
0.00
0.01
0. 36
0.0')
0.46


0. 52
0,22
0.74
                                                   61.4
                                                                                    64.6
                                                                   60.9

                                                               B75123044a

-------
              TABLE  29.   THERMOBALANCE  RUN DATA -  VARIOUS COALS  (Continued)
                                         TB-14
Heating Rate, °F/min
Terminal Temperature,  °F
Holding Time, min

Lab Analysis, wt %
   H2O
   Volatile Matter
   Sulfur, wt %, as
      Sulfide
      Sulfate
      Pyritic
      Organic
        Total

Weight, g
   Initial
   Treated
Weight Loss, %
   Of Total Weight
   Of Coal Weight

Reduced Data
   (100 Ib Coal Originally)
   Weight, Ib
   Sulfur Weight, Ib, as
      Sulfide
      Sulfate
      Pyritic
      Organic
        Total

   Sulfur Content, wt %,  as
      Sulfide
      Sulfate
      Pyritic
      Organic
        Total

   Wt % Original Sulfur Removed
      From  Feed
Pittsburgh Seam (W. Va. )
5
900
30
Coal
7.7
33.8
0.00
0.05
1.49
1. 37
2.91


100. 00
0.00
0.05
1 . 49
1. 37
2.91
0.00
0. 05
1.49
1. 37
2.91
Mixture

0.00
0.02
0. 50
0. 46
0. 98
4. 5220

300. 00
0. 00
0. 05
1.49
1. 37
2.91
0.00
0.02
0. 50
0.46
0.9B
Residue

0. 10
0.06
0. 11
0.33
0. 60
3.9811
11.98
35.96
264.04
0.26
0. 16
0.29
0.87
1. 58
0.45
1. 35
1.80

TB-15

Montana Subbituminous
5
900

Coal
1771T
35.7
0.00
0.00
0.29
0. 37
0766




100.00
0.00
0.00
0.29
0. 37
0. 66
0.00
0.00
0.29
0. 37
0. 66
30
Mixture


0.00
0.00
0. 10
0. 12
0.22
4.2117



300. 00
0.00
0.00
0.29
0. 37
0766
0.00
0.00
0. 10
0. 12
0.22

Residue


0.02
0.04
0. 10
0.06
0772

3. 5817
14.96
44.88
255. 12
0.05
0. 10
0.26
0. 15
0.56


0.47
0.27
0.74

TB-16
Illinois No.
S
900

Coal
24.5
32.0
0.00
0.04
0.21
0.28
0. 53




100.00
0.00
0.04
0.21
0.28
0. 53
0.00
0.04
0.21
0.28
0.53
30
Mixture


0.00
0.01
0.07
0.09
0. 17
4.7967



300.00
0.00
0.04
0.21
0.28
0. 53
0.00
0.01
0.07
0.09
0. 17

6

Residue


0.01
0.08
0. 16
0.00
0.25

4.0177
16.24
48.72
251.28
0.02
0.20
0.40
0.00
0.62


0.78
0.00
0.78
60. 1
                             37.9
       24. 5


B75123044a

-------
                              TABLE  29.    THERMOBALANCE  RUN  DATA - VARIOUS  COALS  (Continued)
oo
Run No.
Coal Type
Heating Rate,  °F/min
Terminal Temperature,
Holding Time, min

Lab Analysis,  wt %
   H2O
   Volatile Matter
   Sulfur, wt %, as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total

Weight, g
   Initial
   Treated
Weight Loss, %
   Of Total Weight
   Of Coal Weight
               Reduced Data
                  (100 Ib Coal Originally)
                  Weight, Ib
                  Sulfur Weight, Ib, as
                     Sulfide                   0.00
                     Sulfate                   0.07
                     Pyritic                   2.30
                     Organic                  0.97
                       Total                  3. 34

                  Sulfur Content,  wt %,  as
                     Sulfide                   0.00
                     Sulfate                   0.07
                     Pyritic                   2. 30
                     Organic                  0.97
                       Total                  3. 34

                  Wt % Original Sulfur Removed
                     From Feed
TB-17
W.


Coal
5.9
33.4
0.00
0.07
2. 30
0.97
3. 34
Kentucky
5
800
30
Mixture


0.00
0.02
0.77
0. 32
No. 9


Residue


0.57
0.06
0. 57
0. 30
1. 50
                                                        4.0215
                             100.00    300.00
                                         0.00
                                         0.07
                                         2. 30
                                         0.97
                                         3. 34
                                         0.00
                                         0.02
                                         0.77
                                         0. 32
                                         1.11
 3.7017

 7.95
23. 85
                                                 276. 15
 a
 v*
 00
 a
 p


Coal
5.
24.
0.
0.
1.
0.
1.




100.
0.
0.
1.
0.
K
0.
0.
1.
0.
1.
8
8
00
00
14
04
18




00
00
00
14
04
18
00
00
14
04
18
TB
-18
Illinois No. 6
5
900
30
Mixture


0.
0.
0.
0.
0.
4.



300.
0.
0.
1.
0.
l-
0.
0.
0.
0.
0.


00
00
38
01
39
9714



00
00
00
14
04
18
00
00
38
01
39


Residue


0.
0.
0.

-------
   TABLE  29.    THERMOBALANCE  RUN  DATA- VARIOUS  COALS (Continued)
Ron No.
Coal Type
Heating Rate, T/tnin
Terminal Temperature, °F
Holding Time, min

Lab Analysis, wt %
   HZO
   Volatile Matter
   Sulfur, wt %, as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total

Weight,  g
   Initial
   Treated
Weight Loss, %
   Of Total Weight
   Of Coal Weight

 Reduced Data
   (100 Ib Coal Originally)
   Weight,  Ib
   Sulfur Weight, Ib,  as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total

    Sulfur Content, wt %. as
      Sulfide
      Sulfate
       Pyritic
       Organic
         Total

    Wt % Original Sulfur Removed
       From Feed

w,

Coal
5.9
33.4
0.00
0.07
2.30
0.97
3. 34





100.00
0.00
0.07
I. 30
0.97
3; 34
0.00
0.07
2.30
0.97
3.34

TB-20
. Kentucky
5
1450
30
Mixture


0.00
0.02
0.72
0. 30
1.04
4. 6539




321.03
0.00
0.07
2. 30
0.97
3. 34
0.00
0.02
0.72
0.30
1.04


No. 9

Residue


0. 87
0.02
0. 16
0.21
1.26

3.9515

15.09
48.45
272. 59
2. 37
0.05
0.43
0. 57
3.42


0. 83
1. 11
1.94
70. 1

TB-21

Illinois No. 6
5
900

Coal
6. 6
28.5
0.00
0.00
0.81
0.24
1.05





100.00
0.00
0.00
0.81
0.24
1.05
0.00
0.00
0.81
0.24
1.05

30
Mixture


0.00
0.00
0.27
0.08
OT35
4.8698

t


300.00
0.00
0.00
0.81
0.24
1.05
0.00
0.00
0.27
0.08
0.35


Residue


0.05
0.04
0.14
0.09
OT32

4.4626

8.36
25.08
174.92
0. 14
0.11
0.38
0.25
0.88


0.51
0.33
0.84
40.00
B75123044b

-------
 evaluation.  Therefore, the Western Kentucky No. 9 coal was selected for
 extensive  study  in this program.


 THERMOBALANCE  TESTS - WESTERN KENTUCKY NO. 9

      Five  runs,  TB-22 to TB-26, were made with crushed and screened (—20+80
 mesh) Western  Kentucky No. 9 coal.  This coal was mixed with lime for three
 tests;  Runs TB-24 and TB-26 used coal only.  The heat-up rate was 5°F/min to
 a  terminal temperature of 800°F for Run TB-22 and 900°F for the others.  All
 tests included holding the sample for 30 minutes at the terminal temperatures.

     Data  and  calculations for these five runs are in Table 30.  The sulfur
 removal ranged from 44% to 63% in these tests; however, the fraction of sulfur
 remaining  in the treated coal was still too great to meet the requirements of
 direct  combustion of  the product.  The lowest sulfur content was 1.73%,
 exceeding  the  limits.  More severe treatment was necessary.

     Two important facts were established in these tests.  First^ the sulfide
 content of the residues was much lower in the lime-free tests than in the tests
 with lime.  This proves that calcium sulfide forms, but not so fast as the
 sulfur  is  released from the coal, as shown by an imbalance in total sulfur.

     Second, the residue was caked in the sample basket and had to be broken
 up for  removal and analysis.  Poor solids-gas contact results from the caking
 and the reactions are inhibited; sulfur removal should be enhanced if the coal
 is noncaking.

     A  pretreatment step is required, for some coals, to prevent caking at the
 thermobalance  conditions.  The caking is caused by the tendency of the coal to
 become  fluid at  elevated temperatures.  When partially fluid, the coal parti-
 cles stick together.  The coal can be pretreated by heating to a certain
 temperature, usually  750  to 800°F, in an atmosphere of air until a small
 quantity of oxygen has been consumed.  Under these conditions, the "volatile
 matter" content  of the coal is reduced and the coal no longer becomes  fluid at
 the test temperature.  Also, the coal particles form a skin, probably  coke or
 char, that can be evaluated microscopically.  This skin also inhibits  caking.
 A  batch reactor  (modified) was used to pretreat coals for the test work.

     Western Kentucky No. 9 coal is relatively easy to pretreat.  The  caking
 tendencies can be destroyed by heating the coal, fluidized with air at atmo-
 spheric pressure, to 750 F, reacting 1 SCF of oxygen per pound of coal.  This
 coal can also  be pretreated using inert nitrogen treatment at  750°F for  30
minutes.  Associated with the pretreatment is a weight loss of 15% total (11%
 to  12%  on a dry  basis), including coal fines lost overhead.  Volatile  matter
 content is reduced from 33% to 35% in the coal to 27% to 28% in the pretreated
coal.    Its bulk  density also decreases from about 50 Ib/cu ft  to approximately
35 Ib/cu ft,  because the particles tend to "puff."  Other coals are pretreated
in a similar manner but may require more air, longer exposure  time, or higher
temperatures.
                                      80

-------
TABLE 30.  THERMOBALANCE RUN DATA (WESTERN KENTUCKY NO. 9)
Run No.
Coal Type
Heating Rate, °F/min
Terminal Temperature, °F
Holding Time, min
Lab Analysis, wt %
HZ0
Volatile Matter
Sulfur, wt %, as
Sulfide
Sulfate
Pyritic
Organic
Total
Weight, g
Initial
Treated
Weight Loss, <#>
Of Total Weight
Of Coal Weight
Reduced Data
(100 lb Coal Originally)
Weight, lb
Sulfur Weight, lb, as
Sulfide
Sulfate
Pyritic
Of panic
\_/ 1. gmxLv^
Total
Sulfur Content, wt % , as
Sulfide
Sulfate
Pyritic
Organic
Total

W.



Coal
5.9
33.4

0.00
0. 07
2. 30
0. 97
3. 34










0. 00
0. 07
2. 30
0. 97
3. 34

0.00
0. 07
2. 30
0. 97
3. 34
TB-22
Ky. No.
5
800
30
Feed



0. 00
0.02
0.77
0. 32
1. 11

4. 5805






300. 00

0. 00
0. 07
2. 30
0. 97
3. 34

0.00
0.02
0.77
0.32

1. 11

9



Residue



0. 30
0.07
0. 34
0. 34
1.05


4. 1764

8.82
26.48


273. 52

0. 82
0. 19
0. 93
0. 93
2.87



1. 26
1. 26

2. 52
Wt % Original Sulfur Removed

From Coal

From Feed
*No lime.










44. 3

44. 3


                                                      TB-23
W.



Coal
5.9
33.4
0.00
0.07
2. 30
0. 97
3. 34





0. 00
0. 07
2. 30
0. 97
3.34
0.00
0.07
2. 30
0. 97
3.34


Ky. No.
5
900
30
Feed


0.00
0.02
0.77
0. 32
1. 11
4. 5869



300. 00
0.00
0. 07
2. 30
0. 97
3. 34
0.00
0. 02
0.77
0. 32
1. 11


9



Residue


0. 59
0. 05
0. 32
0. 30
1. 26

4. 1125
10. 34
31. 02
268. 98
1.59
0.13
0.86
0.81
3. 39


1,25
1. 17
2.42
50.0
50.0
                                                            B75123043
                              81

-------
TABLE 30.   THERMOBALANCE RUN DATA (WESTERN KENTUCKY NO.  9)  (Continued)
                                  W. Ky. No.  9
                                        5
                                       900
                                       30
                                 Coal    Residue
                                  5.9
                                 33.4
 Run No.                               TB-24*
 Coal Type
 Heating Rate, °F/min
 Terminal Temperature, °F
 Holding Time,  min
 Lab Analysis, wt %
    H20
    Volatile Matter
    Sulfur, wt %,  as
       Sulfide                      0.00       0.72
       Sulfate                      0. 07       0. 05
       Pyritic                     2. 30       0.64
       Organic                     Q. 97       1. 09
          Total                     3. 34       2. 50
 Weight, g
    Initial                        4. 2304
    Treated                                  3. 0028
 Weight Loss, %
    Of Total Weight                            29. 02
    Of Coal Weight                            29.02
 Reduced Data
    (100 Ib Coal Originally)
    Weight, Ib                   100.00       70.98
    Sulfur Weight, Ib,  as
      Sulfide                       0. 00       0. 51
      Sulfate                       0. 07       0. 04
      Pyritic                      2. 30       0.45
      Organic                     0. 97       0. 77
         Total                     3.34       1.77
    Sulfur Content, wt  % , as
      Sulfide                       0. 00
      Sulfate                       0. 07
      Pyritic                       2. 30       0. 64
      Organic                     Q. 97        1. 09
         Total                     3.34        1.73
    Wt <£ Original Sulfur Removed
      From Coal                               63.5
      From Feed                               63.5
*No lime.
                                                                TB-25
W



Coal
5.9
33.4
0. 00
0.07
2. 30
0. 97
3.34





0.00
0.07
2.30
0. 97
3.34
0. 00
0.07
2.30
0. 97
3.34


. Ky. No.
5
900
30
Feed


0.00
0. 02
0.77
0. 32
1. 11
4. 5726



300. 00
0.00
0.07
2.30
0. 97
3. 34
0.00
0.02
0.77
0. 32
1.11


9



Residue


0.36
0.04
0. 18
0. 37
0.95

4.0582
11. 25
33. 74
266. 26
0. 96
0.11
0.48
0.99
2. 54


0.72
1.49
2. 21
56.0
56.0
                                                                       B75123043
                                       82

-------
TABLE 30.   THERMOBALANCE RUN DATA (WESTERN  KENTUCKY NO.  9) (Continued)
                 Run No.
                 Coal Type
                 Heating Rate,  ° F/min
                 Terminal Temperature, °F
                 Holding Time, min
                 Lab Analysis, wt %
                    H20
                    Volatile Matter
                    Sulfur, wt % ,  as
                       Sulfide
                       Sulfate
                       Pyritic
                       Organic
                          Total
                 Weight, g
                    Initial
                    Treated
                 Weight Loss, %
                    Of Total Weight
                    Of Coal Weight
                 Reduced Data
                    (100 Ib Coal Originally)
                    Weight,  Ib
                    Sulfur Weight, Ib,  as
                       Sulfide
                       Sulfate
                       Pyritic
                       Organic
                         Total
                    Sulfur Content, wt %,  as
                       Sulfide
                       Sulfate
                       Pyritic
                       Organic
                         Total
                    Wt "Ir Original Sulfur Removed
                       From Coal
                       From Feed
                *No lime.
      TB-26*
   W. Ky. No. 9
        5
       900
        30
  Coal    Residue
5.9
33.4
0.00
0.07
2. 30
0. 97
3.34


0.73
0.00
0.75
1.03
2.51
3.8131
100.00
2.7383

 28.19
 28.19


 71.81
0.00
0.07
2.30
0. 97
3.34
0.00
0.07
2.30
0.97
3.34
0.52
0.00
0.54
0.74
1.80


0.75
1.03
1.78
             61.7
             61.7
           B75123043
                                            83

-------
      A quantity of the Western Kentucky No.  9 coal was  pretreated  as described.
 The pretreated coal was then screened to —20+40 mesh for use in the thermo-
 balance and batch reactor tests.   All subsequent calculations for  the tables
 sire based on a coal-lime feed that is made by taking an initial 100 pounds  of
 wet coal, pretreating it, and mixing the pretreated coal with lime (—60+80
 mesh) in a 1:2 coal/lime ratio.

      Results from a series of tests using pretreated coal are shown in Table 31.
 Sulfur removals of 65% to 90% were attained.   The first two  runs,  TB-27 and
 TB-28, were heated at 5°F/min to  900°F terminal temperature  and held for 30
 minutes.  Test TB-28 was run without lime.   A reduction of pyritic sulfur was
 achieved with the formation of sulfide.  Much more sulfide was made in the  test
 with the lime than in the no-lime case.  The organic sulfur  reduction in these
 two tests, however, is about equal to the weight loss.   The  lower  organic
 sulfur content in the residue from in the test with coal (no lime) may be due
 to sulfur-bearing oils and tars that are absorbed by the lime in the mixed-feed
 tests.  These tests still yield a coal residue that is  too high in sulfur.

      Runs TB-30 and TB-31, also presented in Table 31,  were  heated to 1500°F
 at 5°F/min with no holding.  As expected, weight losses were much  higher at
 these temperatures.  The residue  from Test TB-30 has a  lower sulfur content
 than most of the earlier runs; however, it is difficult to allocate the sulfur
 to the coal and lime when the residue is analyzed totally.   Therefore, Test
 TB-31 was made at the same condition and the residue was separated by the float-
 sink method described earlier. The two fractions were  then  analyzed.  The
 removal of sulfur and redistribution of the  total original sulfur  is nearly the
 same for Tests TB-30 and TB-31.  The total amount of sulfur  remaining after
 treatment (per 100 pounds of initial coal) is 1.84 pounds for Test TB-30 and
 1.83 pounds for Test TB-31.  The  distribution of the sulfur  by types is also
 similar.  Assuming that the sulfide and sulfate remaining in the treated coal
 can be washed or mechanically separated, the coal residue contains only 0.66%
 total sulfur.  This is an acceptable value depending upon the heating value of
 the coal residue.

      For additional comparisons,  three more  tests, shown in  Table  32, were  run
 at a terminal temperature of 900°F and held  for 30 minutes.   The residue was
 separated by the float-sink method or screened at 50 mesh into +50 and —50
 fractions.   The sulfur data from  the different separation techniques scattered
 widely;  however,  all sulfur contents were above the acceptable limits.  The
 conclusion,  at this point, is that 900°F is  not severe  enough treatment to
 effectively remove sulfur.

      Table 33 lists the results and calculations from runs made at a heating
 rate of  5°F/min to a terminal temperature of 1500°F with no  holding time.  All
 tests show good sulfur removal with a range  of 0.52% to 0.81% total sulfur  in
 the  coal residue  (float or +50 mesh).   Total weight loss (pretreatment and
 hydrogen treatment)  is about 50%.   Some of the loss is  from  the moisture content
 of the raw coal,  and some losses  will be recoverable as useful tars, oils,  and
 gases from the process.

      Two  of  the runs,  TB-53 and TB-54,  were  made without lime.  The residues
were  separated by the  two methods as indicated in Table 33.   This  was done to
                                      84

-------
00
Oi
                                   TABLE  31.   THERMOBALANCE  RUN DATA (PRETREATED  WESTERN  KENTUCKY  NO.  9)
Run No.
Coal Type
Heating Rate, °F/min
Terminal Temp, °F
Holding Time, min
Lab Analysis, wt %
   H20
   Volatile Matter
   Sulfur, wt %, as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total
   Weight, g
      Initial             1
      Treated
   Weight LOBS, %
      Qt Total Weight
      Of Coal Weight
 Reduced Data
    (100  Ib Original Coal)
    Weight, Ib            1
    Sulfur Weight,  Ib, as
       Sulfide
       Sulfate
       Pyritic
       Organic
          Total
    Sulfur Content, wt %, as
       Sulfide
       Sulfate
       Pyritic
       Organic
          Total
    Wt %,  Original Sulfur
       Removed From Feed
       Removed From Coal

   No lime.
                                                                TB-27
                                                        Pretreated W. Ky.  No. 9
                                                                  5
                                                                 900
                                                                 30
                                                                                       TB-28*
                                                                                                            TB-30
                                                                                                                                       TB-31
            Pretreated W. Ky. No. 9  Pretreated W. Ky. No. 9
                     5                      5
                    900                   1500
                     30                     0
                                     Pretreated W. Ky. No. 9
                                              5
                                             1500
                                              0
Coal Pretreated Coal
5. 9
33.4
0.00
0.07
2. 30
0.97
3.34
0.8
24.4
0. 14
0. 18
1.40
1.34
3.06
Feed


0.05
0.06
0.47
0.45
1.03
Residue


0. 38
0.06
0.16
0.40
1.00
Feed


0. 14
0.18
1.40
1.34
3.06
Residue


0.68
0.14
0.49
1.13
Z.44 '
Feed


0.05
0.06
0.47
0.45
1.03
Residue


0.46
0.00
0.13
0.21
0.80
Feed


0.05
0.06
0.47
0.45
1.03
Float


0.08
'0.00
0.54
0.12
0.74
Sink


0.63
0.03
0.10
0.07
0.83
                                                         4.8760
                                                                               3. 1496
                                   4.5381
                                                          256.62
4. 5595

  6.49
 19.47
239. 96
                                                                                85.54
2. 7452

 12.70
 12.70
 74.67
256.62
4.0333

 11. 12
 33.37


228.08
0.00
0.07
2. 30
0. 97
3. 34
0.00
0.07
2.30
0.97
3.34



0.12
0. 15
1.20
1. 15
2.62


1.40
1.34
2.74

29.6

0.12
0.15
1.20
1. 15
2.62
0.05
0.06
0.47
0.45
1.03



0.91
0.14
0.38
0.96
2.39


0. 55
1.39
1.94
48. 9
59.9

0.12
0.15
1.20
1.15
2.62


1.40
1.34
2.74

29.6

0.51
0.10
0.37
0.84
1.82


0.49
1.13
1.62
53.8
63.8

0.12
0.15
1.20
1.15
2.62
0.05
0.06
0.47
0.45
1.03



1.05
0.00
0.30
0.49
1.84


0.53
0.86
1.39
69.8
76.3

0.12
0.15
1.20
1.15
2.62
0.05
0.06
0.47
0.45
1.03



0.04
0.00
0.30
0.07
0.41


0.54
0.12
0.66
85.9
88.9
B75123026
1.08
0.05
0.17
0.12
1.42
•








-------
                       TABLE  32.    THERMOBALANCE  RUN DATA  (PRETREATED  WESTERN  KENTUCKY  NO.  9  COAL,  900°F)
oo
Run No.
Coal
Heating Rate, ° F/min
Terminal Temperature, ° F
Holding Time, min
Lab Analysis, wt %
H2O
Volatile Matter
Sulfur, wt %, as
Sulfide
Sulfate
Pyrittc
Organic
Total
Weight, g
Initial
Treated
Weight Loss, %
Of Total Weight
Of Coal Weight
Reduced Data
(100 Ib Coal in Feed)
Weight, Ib
Sulfur Weight, Ib, as
Sulfide
Sulfate
Pyritic
Organic
Total
Sulfur Content, wt % , as
Sulfide
Sulfate
Pyrittc
Organic
Total
Pretreatment
W.



Coal
5. 9
33.4

0. 00
0. 07
2. 30
0. 97
3. 34

100. 00






100. 00

0. 00
0. 07
Z. 30
0. 97
3. 34

0. 00
0. 07
2. 30
0. 97
3. 34
Ky. No. 9

750

Pretreated Cr^l
1. 8
32. 3

0. 13
0. 19
2.87
1^29
4. 48


85. 54

14.46
14.46


85. 54

0. 11
0. 16
2.45
1. 10
3.82



2.87
1.29
4. 16
                                                                         TB-34
                                                                                                 TB-42
                                                                  Pretreated W. Ky.  No.  9   Pretreated W. Ky. No. 9
                                                                           5                        5
                                                                           900                     900
                                                                           30                      30
                                                                   Feed    Float    Sink   Feed     +50     —50
                                                                   0. 04
                                                                   0. 06
                                                                   0. 96
                                                                   0. 43
                                                                   1.49

                                                                 4. 2716
                                                                   0. 11
                                                                   0. 16
                                                                   2.45
                                                                   1. 10
                                                                   3.82
                                        	TB-33	
                                        Pretreated W. Ky.  No.  9
                                                  5
                                                 900
                                                 30
                                        Feed     +50      -50
  0. 07    0. 33    0.04
  0.00    0.07    0.06
  0. 50    0. 29    0. 96
  1. 04    0. 17    0.43
  1.61    0.86    1.49
                1.22    0.27    0.04
                0.01    0.04    0.06
                0.64    0. 00    0. 96
                1. 36    0. 21    0.43
                3.23    0.52    1.49
                                0.86
                                0.05
                                1.00
                                0. 92
                                2.83
                                 0.22
                                 0.04
                                 0.11
                                 0.09
                                 0.46
                                                                                        4. 5483
                                      4. 1169
0.9279  2.9854

      7. 94
     23.81
              1.1509  2.9930

                   7.94
                  23.83
                              1.0293   2.7387

                                    7.82
                                   23.47
                                                                 256.62   56.02  180.22 256.62    65.61  170.63  256.62   64.62   171.93
              Wt % Original Sulfur Removed
                 From Feed
  0.04
  0.00
  0. 28
  0. 58
  0. 90
  0. 50
  1.04
  1. 54

  56.6
0. 59
0.13
0. 52
0. 31
1. 55
0. 11
0.16
2.45
1.10
3. 82
0. 80
0.01
0.42
0.89
2. 12
                0.64
                1. 36
                2.00

                43.7
0.46
0.07
0.00
0. 36
0.89
0. 11
0.16
2.45
1.10
3.82
0. 56
0.03
0.65
0. 59
1.83
                                1.00
                                0.92
                                1.92

                                45. 9
0. 38
0.07
0.19
0.15
0.79
                                B75123046

-------
                      TABLE  33.   THERMOBALANCE RUN  DATA  (PRETREATED WESTERN KENTUCKY NO.  9 COAL,  1500°F)
oo
Run No.
Coal Type
Heating Rate, °F/min
Terminal Temperature,
Holding Time, min

Lab Analysis, wt %
   H20
   Volatile Matter
   Sulfur, wt %, as
      Sdlfide
      Sulfate
      Pyritic
      Organic
        Total

Weight, g
   Initial
   Treated
Weight Loss, %
   Of Total Weight
   Of Coal Weight
                                          Pretreatment
                                                                    TB-35
                                                                                                   TB-45
                                                                                                                                   TB-52
W.  Kentucky No. 9  Pretreated W.  Kentucky No. 9
                                5
       750                    1500
                                0
       Pretreated
Coal     Coal      Feed     +50      - 50
                                                                                         Pretreated W. Kentucky No. 9
                                                                                                       5
                                                                                                    1500
                                                                                                       0
                                                                                                            Pretreated W. Kentucky No.
                                                                                                                          5
                                                                                                                       1500
                                                                                                                          0
                                                                                          Feed
                                                                                                     Float
                                                                                                               Sink
                                                                                                                          Feed
                                                                                                                                    Float
                                                                                                                                             Sink
5.9
33.4
0.0
0.07
2.30
0.97
3.34
1.8
32.3
0.13
0.19
2.87
1.29
4.48


0.04
0.06
0.96
0.43
1.49


0.00
0.02
0.28
0.39
0.69


0.88
0.08
0.15
0.24
1.35


0.04
0.06
0.96
0.43
1.49


0.05
0.01
0.31
0.51
0.88


0.83
0.13
0.11
0.31
1.38


0.04
0.06
0.96
0.43
1.49


0.13
0.00
0.05
0.69
0.87'


1.14
0.09
0.01
0. 10
1.34
                                      100.00
        85. 54

        14.46
        14.46
                                                           4.4377
                                                                                          4.4377
                                                                    0.9085
                                                                               2.9429
                                                                                                    0.8339
                                                                                                               3.2445
                                                                                                             4. 3962
    12.82
    38.45
                                                                                                          12.54
                                                                                                          37.60
                                                                                                                       0.7817   2.9114

                                                                                                                            12.89
                                                                                                                            38.68
Reduced Data
(100 Ib Coal Originally)
Weight, Ib
Sulfur Weight, Ib, as
Sulfide
Sulfate
Pyritic
Organic
Total
100.00
0.00
0.07
2.30
0.97
3.34
85.54
0.11
0. 16
2.45
1.10
3782
256.62
0.11
0.16
2.45
1.10
3.82
52.77
0.00
0.01
0.15
0.21
6737
170.95
1.50
0.14
0.26
0.41
2. 31
256. 62
0. 11
0. 16
2.45
1. 10
3. 82
46.42
0.02
0.01
0. 14
0.24
0.41
180.59
1.50
0.23
0.20
0.56
2.49
256.62
0. 11
0. 16
Z.45
1.10
3.82
47. 32
0.06
0.00
0.02
0.33
074T
176.22
2.01
0. 16
0.02
0.18
2. 37
Sulfur Content, wt%, as
   Sulfide                   0.00
   Sulfate                   0.07
   Pyritic                  2. 30
   Organic                  0.97
     Total                 3.34

Wt % Original Sulfur Removed
   From Feed
          2.87
          1.29
          47T6-
0.28
0. 39
0. 67
                                                                   81. 1
                                                                                                    0.31
                                                                                                    0.51
                                                                                                    0.82
                                                                                                   76.9
                                                                                                                          0.05
                                                                                                                          0.69
                                                                                                                          0.74
                                                                                                                                   90.8
                                                                                                                                       D75123027a

-------
               TABLE  33.    THERMOBALANCE  RUN DATA  (PRETREATED  WESTERN KENTUCKY NO.  9 COAL, 1500°F)  (Continued)
oo
oo
 Run No.
 Coal Type
 Heating Rate,  "F/min
 Terminal Temperature, °F
 Holding Time, rnin

 Lab Analysis,  wt %
   H20
   Volatile Matter
   Sulfur, wt %, as
      Sulfide
      Sulfate
      Pyritic
      Organic
        Total

Weight,  g
   Initial
   Treated
Weight Loss, %
   Of Total Weight
   Of Coal Weight

Reduced Data
   (100 Ib  Coal Originally)
   Weight, Ib
   Sulfur Weight,  Ib,  as
     Sulfide
     Sulfate
     Pyritic
     Organic
        Total

   Sulfur Content, wt%, as
     Sulfide
     Sulfate
     Pyritic
     Organic
       Total

  Wt % Original Sulfur Removed
     From Feed
      *No lime.
                                                TB-53*
                                      Pretreated W. Kentucky No. 9
                                                    5
                                                 1500
                                                    0
                                                                             TB-54*
                                       Feed
                                       4.7038
                                      85.54
                  Pretreated W. Kentucky No. 9
                                5
                              1500
                                0
                                                                                                             TB-57
         Pretreated W. Kentucky No. 9
                       5
                    1500
                       0
                                                                                                                                         TB-58
                 Pretreated W. Kentucky No. 9
                              5
                            1500
                              0
                                                  50
                                                         - 50
                                                                   Feed
                                                                               Float
                                                                                         Sink
                                                                                                    Feed
                                                                                                              Float
                                                                                                                       Sink
                                                                                                                                Feed
                                                                                                                                         Float
                                                                                                                                                  Sink
0.13
0.19
2.87
1.29
4.48
0.44
0.00
0.34
0. 19
0.97
2.00
0.00
0. 18
1.22
3.40
0.13
0.19
2.87
1.29
4.48
0.15
0.00
0.45
0.07
0.67
2.13
0.02
0.10
0.36
2.61
0.04
0.06
0.96
0.43
1.49
0.06
0.02
0.00
0.81
0.89
0.24
0.40
0.06
0.43
1.13
0.04
0.06
0.96
0.43
1.49
0.14
0.00
0.45
0.36
0.95
0.67
0.14
0.01
0.38
1.20
2.611    0.2407


     38.29
                                                                   2.8771
                                                                                                    4. 6800
                                                                               1.4686
0.2936
                                                                                    38.75
                  4.9088
0.1428   3.8901            0.8846   3.5508

    13.83                       13.64
                                               48.41
                                                         4.38
                                                                  85.54
                             43.66
                                                                                         8.73
                                                                                                  256.62
                     7.92   215.78   256.62
                          44.20   177.42
0.11
0. 16
2.45
«. 10
3.82
0.21
0.00
0. 17
0.09
0~47
0.09
0.00
0.01
0.05
oTTs
0.11
0.16
2.45
1.10
3.82
0.06
0.00
0.20
0.03
0.29
0.19
0.00
0.01
0.03
0.23
0.11
0.16
2.45
1.10
3.82
0.01
0.00
0.00
0.06
0.07
0.52
0.86
0.13
0.93
2.44
0.11
0.16
2.45
1.10
3.82
0.06
0.00
0.20
0.16
0.42
0.19
0.25
0.02
0.67
1.13
                                                0.34
                                                0. 19
                                                0753
                                               93.2
                                                              0.00
                                                              0.81
                                                              WTST
                                                                              94.0
                                                0.45
                                                0.36
                                                0.81
                                                                                        78.8


                                                                                    D75123027b

-------
determine the amount of  treated material that would report to the lime
portion  (sink or —50 mesh)  in the tests using mixed feed.   In TB-53,  8.3%
of the treated coal material remaining was -50 mesh, while 16.7%  in'lB-54
was in the sink portion.  The treated material splits are  assumed to  occur in
this way in the tests with  lime.  Also, the -50 and sink fractions have much
higher sulfide and organic-type sulfur percentages than the +50 or float
portions.  This effect could be used in further sulfur reduction.

     Run TB-57 was made  with the pretreated material ground to -80 mesh and
then mixed, treated, and separated.   A disproportionately  large portion of the
treated material went to the sink portion of the separated material,  making
conclusions difficult.

     The other runs  (TB-35,  TB-45,  TB-52, and TB-58) were  made with the usual
coal-lime mix.  They were screen- or float-separated as shown.  Higher weight
loss is experienced in the  float-sink technique than in the screen separation,
as illustrated by Runs TB-53 and TB-54.  Assuming that the sulf ide and sulf ate
can be removed by chemical  or mechanical means, the coal-fraction  sulfur con-
tent of these runs ranges from 0.52% to 0.82%.   Heating values of  8,667 to
13,667 Btu/lb of treated material would give S02 emissions of  1.20 lb/106 Btu
for these tests.  Heating values from the early batch tests (Table 9) are
12,699 to 12,920 Btu/lb.  If similar values are assumed for this material,
only the higher sulfur content material would exceed the allowable limits.

     The next set of runs,  shown in Table 34, are those heated to  1500°F at
5°F/min and then held for 30 minutes at the final temperature.  In Runs TB-61
and TB-63, nitrogen was  used for initial preheat to 700°F  and hydrogen to the
end of the run.  Runs TB-62  and TB-63,  made with —80 mesh  pretreated  coal, have
poor coal-fraction recovery.   All tests show a lower total sulfur  content,
ranging from 0.36% to 0.75%,  indicating that the holding time  is beneficial.
S0? emission again depends upon the heating value of the recovered coal portion,
but is in the proper range.

     Table 35 presents runs  that were heated at 5°F/min to 1500°F, with no
holding time, but had various feed or operational changes.   Runs TB-59 and
TB-60 were made with —80 mesh pretreated coal only.   These tests  exhibit a
good final sulfur content (0.50% to  0.55%)  indicating that the lime may not be
imperative at elevated temperatures.   The float-sink technique was used to
determine how the finely ground material would  separate.   Losses to the sink
fraction may cause a reevaluation of  separation techniques when using lime.

     Run TB-64 was made  with the usual  size coal and mixture, but  was heated
to 700°F with nitrogen and then with hydrogen the remainder of the time to the
terminal temperature of  1500°F.   The sulfur content of the product is in the
higher end of the range  and  the separation was  poor,  indicating 1) this treat-
ment is not beneficial,  and  2)  some  sulfur reacts with the hydrogen at lower
temperatures.

     The pretreated coal  feed for Run TB-65 was subjected  to a 1:7 HNO^ solu-
tion for 1 hour under reflux.   These conditions are similar to the ASTH method
for FeS, extraction.  Afterward the  coal was washed,  filtered, dried, ground
to -20+40 mesh,  and mixed with lime  in  the usual ratio for the test.  The


                                       89

-------
        TABLE  34.   THESMOBALANCE  RUN DATA  (PRETREATED WESTERN KENTUCKY NO.  9,  1500°F,  30 min)
                           100.00
Run No.
Coal Type
Heating Rate,  °F/min
Terminal Temperature,  °]
Holding Time,  min

Lab Analysis, wt %
   H2O
   Volatile Matter
   Sulfur, wt %,  as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total

Weight, g
   Initial
   Treated
Weight Loss, %
   Of Total Weight
   Of Coal Weight

Reduced Data
   (100 Ib Coal Originally)
   Weight,  Ib
   Sulfur Weight
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total  -
Sulfur Content, wt %, as
   Sulfide                    0.00
   Sulfate                    0.07
   Pyritic                    2. 30
   Organic                   0.97
     Total                   3.34

Wt % Original Sulfur Removed
   From Feed
                              Pretreatment
                             W. Kentucky No. 9
                           100.00
                                   750
          	TB-36	
          Pretreated W. Kentucky No. 9
                         5
                      1500
                        30
                                             TB-37
Coal
•3J4
0.00
0.07
2.30
0.97
3.34
Pretreated
Coal
1.8
32.3
0.13
0.19
2.87
1.29
4.48
Feed
0.04
0.06
0,96
0.43
1.49
Float
0.00
0.06
0.49
0.26
0.81
Sink
0.95
0.05
0.04
0. 32,
T736
                                      85.54

                                      14.46
                                      14.46
85.54
            4.6108
                      0.8837
                       3.2341
                            13.30
                            39.30
256.62
47.45
174.74
0.00
0.07
2.30
0.97
3.34
0.11
0. 16
2.45
1.10
3.82
0.11
0. 16
2.45
1. 10
3.82
0.00
0.03
0.23
0. 13
0.39
1.66
0.09
0.07
0. 56
2. 38
                                                               0.49
                                                               0.26
                                                               0.75
                                                              78.9
                                  Pretreated W. Kentucky No. 9
                                                 5
                                              1500
                                                30
                                                                                   Feed
                                   4.7242
256.62

  0. 11
  0. 16
  2.45
  1.10
  3.82
                                                        Float
                                                         Sink
0.04
0.06
0.96
0.43
1.49
0.04
0.01
0.23
0.32
0.60
0.99
0.06
0.08
0.23
1.36
                                   0.9266
                                    3.1288
                                                     14.48
                                                     43.44
60.14

 0.02
 0.01
 0. 12
 0.16
 0.31
169.32

  1.68
  0.10
  0.14
  0.39
  2.31
                                                                                                84.5
                                                                                                          D75123031

-------
      TABLE  34.  THERMOBALANCE RUN DATA (PRETREATED WESTERN KENTUCKY NO. 9,  1500°F, 30  min) (Continued)
Run No.
Coal Type
Heating Rate,  °F/min
Terminal Temperature,  °F
Holding Time, min

Lab Analysis, wt %
   H2O
   Volatile Matter
   Sulfur, wt %, as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total

Weight, g
   Initial
   Treated
Weight Loss,  %
   Of Total Weight
   Of Coal Weight

Reduced Data
   (100 Ib Coal Originally)
   Weight, Ib
   Sulfur Weight
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total  .

   Sulfur Content, wt %, as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total

   Wt % Original Sulfur Removed
      From Feed

   *"—80 mesh pretreated coal.
           TB-61
                             TB-62*
                                                 TB-63*
Pretreated W. Kentucky No. 9  Pretreated W. Kentucky No. 9
               5                             5
            1500                          1500
              30                            30
  Feed
  1.49
  4.6874
256.62
                                                Pretreated W. Kentucky No.  9
                                                               5
                                                            1500
                                                              30
 Float
Sink
Feed
Float
Sink
                                                              Feed
                                                            Float
                    Sink
0.04
0.06
0.96
0.43
0.32
0.01
[0. 51}
0.80
0.11
{0. 46}
0.04
0.06
0.96
0.43
0.10
0.00
0.36
0.00
0.78
0. 12
0. 13
0.40
0.04
0.06
0.96
0.43
0.23
0.05
0.00
0.71
0.64
0.14
0. 11
0.40
 0.84
1.37
1.49
                    4.9800
0.46
1.43
             0.9437    3.0926

                  13.89
                  35.49
51.66    169.31    256.62
                              0.1563   4.0783

                                   14.97
                                   44.90
                   8.05    210.15
1.49
                                                              4.8231
0.99
1.29
                                                            256.62
0. 11
0. 16
2.45
1. 10
0.17
0.01
{0.26}
1.35
0. 19
{0.78}
0.11
0. 16
2.45
1. 10
0.01
0.00
0.03
0.00
1.64
0.25
0.27
0.84
0. 11
0.16
2.45
1. 10
0.02
0.00
0.00
0.05
1.36
0.30
0.23
0.85
                                3.82
                              0.04
                             3.00
                                                              3.82
            {0. 51}
             oTsT


            93.2
                             99.2
                                                           0.00
                                                           0.71
                                                           0.71
                                                                      98.7

                                                                       D75123031

-------
               TABLE 35.  THERMOBALANCE RUN DATA (PRETREATED  WESTERN KENTUCKY NO.
      Run No.
      Coal Type
      Heating Rate, °F/min
      Terminal Temperature,
      Holding Time,  min

      Lab Analysis, wt %
         H2O
         Volatile Matter
         Sulfur, wt %, as
            Sulfide
            Sulfate
            Pyritic
            Organic
               Total
  Pretreatment     	TB-59*	
W. Kentucky No. 9  Pretreated W.  Kentucky No.  9
                                   5
       750                     1500
                                   0
       Pretreated
 Coal     Coal       Feed      Float       Sink      Feed
                                                                                  9,  1500 F, 0 min)

                                                                                               TB-60*
                                                                                    Pretreated W. Kentucky No. 9
                                                                                                  5
                                                                                               1500
                                                                                                  0
5.9
33.4
0.00
0.07
2. 30
0.97
3.34
1.8
32.3
0. 13
0.19
2.87
1.29
4.48


0. 13
0. 19
2.87
1.29
4.48


0. 19
0.00
0.30
0.24
0.73


0. 54
0.00
0.26
0.28
1.08


0. 13
0.19
2.87
1.29
4.48
                                                                                                Float
                                                                                                0.14
                                                                                                0.00
                                                                                                0.27
                                                                                                0.25
                                                                                                076"6
                                                                   Sink
vo
Weight, g
   Inttial                      100.00
   Treated
Weight Loss,  %
   Of Total Weight
   Of Coal Weight

Reduced Data
   (100  Ib Coal Originally)
   Weight, Ib                 100.00
   Sulfur Weight,  Ib, as
      Sulfide
      Sulfate
      Pyritic
      Organic
        Total
         Sulfur Content, wt %, as
            Sulfide
            Sulfate
            Pyritic
            Organic
              Total

         Wt % Original Sulfur Removed
            From Feed
85.54

14.46
14.46
                                               85.54
                                          2.87
                                          1.29
                                                         4.0071
          85. 54
                                                                     1. 4447
                               30.84
                                           1.004
                                                                          38.88
                      0.30
                      0.24
                      5754
                                                             95. 8
21.44
                                           3.9726
85.54
0.00
0.07
2.30
0.97
3.34
0.11
0.16
2.45
1. 10
3.82
0.11
0.16
2.45
1. 10
3.82
0.06
0.00
0.09
0.07
0.22
0. 12
0.00
0.05
0.06
0.23
0.11
0. 16
2.45
1.10
3.82
                        1.9371
                        0.4812
41.88

 0.06
 0.00
 0.11
 0.10
 0.27
                                                                  0.27
                                                                  0.25
                                                                  0.52
                                                       94.5
                                                                        38.87
10.41

 0.09
 0.03
 0.00
 0.05
 0.17
         *No lime.

-------
              TABLE 35.   THERMOBALANCE RUN DATA (PRETREATED WESTERN KENTUCKY NO. 9,  1500°F, 0  min) (Continued)
vD
CO
    Run No.
    Coal Type
    Heating Rate, °F/min
    Terminal Temperature,
    Holding Time, min
                                          TB-64
                           TB-65
                              TB-66
                               Pretreated W. Kentucky No.  9
                                              5
                                           1500
                                              0
                                      0.11
                                      0. 16
                                      2.45
                                      1.10
                                      3.82
                Pretreated W. Kentucky No.
                               5
                            1500
                               0
                   Pretreated W. Kentucky No. 9
                                  5
                               1500
                                  0
Lab Analysis, wt %              Feed       Float      Sink
   H20
   Volatile Matter
   Sulfur, wt %,  as
      Sulfide                    O.Q4
      Sulfate                    0.06
      Pyritic                    0.96
      Organic                   0. 43
         Total                    1.49

Weight,  g
   Initial                        4.8239
   Treated
Weight Loss, %
   Of Total Weight
   Of Coal Weight

 Reduced Data
   (100  Ib Coal Originally)
   Weight, Ib                  256.62
   Sulfur Weight, Ib, as
      Sulfide
      Sulfate
      Pyritic
      Organic                   	        	
         Total                   3.82        0.34     2.04

    Sulfur  Content,  wt %, as
      Sulfide
      Sulfate
      Pyritic
      Organic
          Total

    Wt  % Original Sulfur Remove
       From Feed                            92. 7
                                                                     Feed
                            Float
          Sink
                      Feed
                    Float
                    Sink
0. 16
0.00
0.37
0.38
0.91
0. 53
0. 16
0.01
0.40
1. 10
0.01
0.02
0. 34
0.52
0.89
0.08
0.00
0.35
0.21
0.64 '
0.21
0.11
0.05
0.20
0. 57
0.00
0.01
0.37
0.65
1.03
0.34
0.03
0.73
0.23
1.33
0.60
0.09
0. 13
0.43
1.25
0.7019    3.4910

      13.08
      39.24
                                                 37.34    185.71
                                                                     4.4535
                 256.62
 0.5656   3.8879

      13.36
      40.08
28.24   194.10
                                                  4.4777
         300.00
                     0.0414    3.8316

                           13.50
                           40.50
          2.78   256.72
0.06
0.00
0. 14
0. 14
0.98
0.30
0.02
0.74
0.03
0.05
0. 87
1.33
0.02
0.00
0. 10
0.06
0.41
0.21
0. 10
0. 39
0.00
0.01
0.37
0. 65
0.01
0.00
0.02
0.01
1.54
0.23
0.33
1. 10
                   2.28
 0. 18
                                                                               0.35
                                                                               0.21
                                                                               0756"
                                                                              95. 8
1. 11
1.03
                                                           0.04
                                                           0.73
                                                           0.23
                                                           0.96
                                                                                                            97.1
                                         3.20
                                                                                                                   D75123032

-------
 treatment  reduced  the  pyritic  sulfur by over 50% and the total sulfur to 2.69%.
 After hydrogen treatment,  the  residue contained 0.56% pyritic plus organic
 .sulfur,  similar to other tests.  Therefore, preremoval of pyrite by standard
 washing  techniques is  not  beneficial.

      For Run TB-66,  the raw coal was treated with IN Fe2(SO^>3 (similar to the
 Meyers Process) for 11 hours and then crushed to —80 mesh and mixed with lime.
 The results are not conclusive because of the small amount of float material
 recovered.   The float  material did not have sulfur values as low as previous
 tests indicating (preliminarily) that utilization of the Meyers Process is not
 beneficial as a modification of this process.  However, the Fe^^O,)^ treatment
 did prevent the agglomeration  of the coal and may prove to be a substitute for
 air pretreatment.

      Table 36 lists tests  heated at 10°F/min to 1500°F, with one test being
 held for 30 minutes.   Weight losses and separation values are consistent with
 other tests at this temperature.  Residue sulfur contents are slightly higher
 with this  heat-up  rate, compared with tests at the slower heating rate  (5°F/
 min). The increased coal  residence time associated with the slower rate may
 have caused the improved sulfur removal.  Table 37 presents data at a heat-up
 rate of  20°F/min:   One test was held for 15 minutes, another was held for 30
 minutes, and the rest  had  no holding time.  Weight loss is as expected but the
 sulfur content is  higher at 0.70% to 0.95%.

      A series of tests, Table  38, was heated at 5°F/min to 1300°F; one test
 was held for 30 minutes.   The  results show slightly less weight loss, but the
 sulfur content is  higher at 0.89% to 1.14%.  Because this range is too high,
 it  was concluded that  1300°F is not an adequate treatment temperature.

      One test,  TB-41 (Table 39), was heated at 20°F/min to 1600°F and held for
 30  minutes.   All of  the parameters — weight loss, recovery, and final sulfur
 content  —  are no better than similar tests at 1500°F; therefore, it appears
 that no  benefit is achieved from higher temperature.

      The data on final sulfur  content from all tests are presented in Figures
 31  and 32.   Figure 31  presents those tests heated at 5 F/min.  Sulfur content
 definitely  decreases as the temperature increases to 1500°F.  No definite
 effect is discernible  to prove the value of residence time at the  final
 temperature.

      The tests  at  higher heat-up rates, 10° and 20°F/min, presented  in  Figure
 32,  also exhibit a decrease in sulfur content but the decrease is  not  so great
 as  in the tests at 5°F/min heat-up rate.  Holding the test runs  at the  terminal
 temperature  long enough to make the run times equal may depress  this  line to
 the  level of  the tests on  Figure 31.

 THERMOBALANCE TESTS -  PITTSBURGH SEAM, WEST VIRGINIA

     When the Western  Kentucky No. 9 coal test series was  concluded,  a second
 coal was selected  for  a group  of tests that would be definitive  but not as
 exhaustive.   Pittsburgh seam coal from a West Virginia mine  was  selected as an
Eastern  coal  with  a high-sulfur content.
                                     94

-------
               TABLE  36.   THERMOBALANCE  RUN DATA  (PRETREATED WESTERN  KENTUCKY NO.  9,  10°F/min,  1500 F)
vo
Ui
Run No.
Coal Type
Heating Rate, ° F/min
Terminal Temperature, ° F
Holding Time, min
Lab Analysis, wt %
   H2O
   Volatile Matter
   Sulfur, wt %, as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total
 Weight, g
   Initial
   Treated
 Weight Loss, %
   Of Total Weight
   Of Coal Weight
 Reduced Data
   (100 Ib Coal Originally)
   Weight,  Ib
   Sulfur Weight, Ib, as
       Sulfide
       Sulfate
       Pyritic
       Organic
         Total
    Sulfur Content, wt %, a
       Sulfide
       Sulfate
       Pyritic
       Organic
          Total
    Wt % Original Sulfur Removed
       From Feed
Pretreatment
W.
Coal
5.9
33.4
0.00
0. 07
2. 30
0. 97
3. 34
100. 00



100. 00
0.00
0. 07
2. 30
0. 97
3. 34
0. 00
0. 07
2. 30
0. 97
3. 34
Ky. No. 9
750
Pretreated Coal
1.8
32. 3
0. 13
0. 19
2. 87
1.29
4.48

85. 54
14.46
14.46
85. 54
0. 11
0. 16
2.45
1. 10
3.82


2. 87
1.29
4.16
                                                                      TB-44
TB-51
                                                                                                                        TB-46
Pretreated W. Ky. No. 9
10
1500
0
Feed Float Sink
0.04 0.11 0.84
0.06 0.01 0.06
0. 96 0. 75 0. 11
0.43 0.22 0.19
1.49 1.09 1.20
4. 5669
0.8950 3.1362
12. 56
37.68
256.62 48.51 175.88
0. 11 0.05 1.48
0.16 0.00 0.11
2.45 0.36 0.19
1.10 0.11 0.33
3.82 0.52 2.11
0.75
0.22
0. 97
72.7
Pretreated W. Ky. No. 9
10
1500
0
Feed Float Sink
0.04 0.24 1.04
0.06 0.00 0.09
0.96 0.03 0.00
0.43 0.77 0.17
1.49 1.04 1.30
4.4300
0.9141 3.0170
12.63
37. 90
256.62 52.13 172.08
0.11 0.12 1.79
0.16 0.00 0.15
2.45 0.02 0.00
1.10 0.40 0.29
3.82 0.54 2.23
0.03
0.77
0.80
89.0
Pretreated W. Ky. No. 9
10
1500
30
Feed Float
0.04 0.11
0.06 0.00
0.96 0.76
0.43 0.02
1.49 0.89
4.4200
0.7773
11.
34.
256.62 47.67
0.11 0.05
0.16 0.00
2. 45 0. 36
1.10 0.01
3.82 0.42
0.76
0.02
0.78
78.0


Sink
1.09
0.06
0.11
0. 14
1.40

3.0131
35
05
180. 83
1.97
0. 11
0. 20
0.25
2. 53




B75123075

-------
                TABLE 37.
                   THERMOBALANCE RUN DATA  (PRETREATED WESTERN KENTUCKY NO.  9, 20°F/min, 1500°F)
          Run No.
          Coal Type
          Heating Rate, °F/min
          Terminal Temperature,
          Holding Time, min

          Lab Analysis, wt %
            H;,0
            Volatile Matter
            Sulfur,  wt %, as
               Sulfide
               Sulfate
               Pyritic
               Organic
                  Total
                                  Pretreatment
                                                             TB-43
                                                     TB-47
W. Kentucky No. 9 Pretreated W. Kentucky No. 9
20
750 1500
0

Coal
5.9
33.4
0.00
0.07
2. 30
0.97
3.34
Pretreated
Coal
1.8
32.3
0.13
0.19
2.87
1.29
4.48

Feed


0.04
0.06
0.96
0.43
1.49

Float


0.27
0.00
0.84
0.04
1. 15

Sink


0.81
0.08
0.20
0.24
1. 33
                                                                                   Pretreated W. Kentucky No. 9
                                                                                                20
                                                                                              1500
                                                                                                 0
                                                                                    Feed
                                                      Float
                                             Sink
0.04
0.06
0.96
0.43
1.49
'iQ.28
0.04
0.36
0.54
1.22
0.80
0.14
0.09
0.25
1.28
vo
Weight, g
   Initial                      100.00
   Treated
Weight Loss,  %
   Of Total Weight
   Of Coal Weight

Reduced Data
   (100  Ib Coal Originally)
   Weight, Ib                 100.00
   Sulfur Weight, Ib,  as
      Sulfide
      Sulfate
      Pyritic
      Organic
        Total

   Sulfur Content, wt%, as
      Sulfide                    0.00
      Sulfate                    0.07
      Pyritic                    2. 30
      Organic                   0.97
        Total                   3.34

   Wt % Original Sulfur Removed
      From Feed
85.54

14.46
14.46
                                                  85.54
                                                             4.5063
         256.62
                                                                       0.9437
            3.0073
                                                                            12.59
                                                                            37.77
53. 58
                                                                       0.84
                                                                       0.04
                                                                       0.88
                                                                      75.2
170.73
0.00
0.07
2.30
0.97
3.34
0.11
0.16
2.45
1.10
3.82
0.11
0.16
2.45
1.10
3.82
0. 14
0.00
0.45
0.02
576T
1.38
0. 14
0.34
0.41
2.27
                                            4.0954
256.62
                         0.8857
54.39
                                                                  2.7766
                                       12.37
                                       37.12
                                                       0.36
                                                       0.54
                                                       0.90
                                                                                                        74.6
170.49
0.11
0.16
2.45
1.10
3.82
0.15
0.02
0.20
0.29
0. 66
1.36
0.24
0.15
0.43
2.18

-------
        TABLE 37.   THERMOBALANCE RUN  DATA  (PRETREATED WESTERN KENTUCKY NO.
VO
-J
Run No.
Coal Type
Heating Rate,  °F/min
Terminal Temperature, °F
Holding Time, min

Lab Analysis, wt %
   HZO
   Volatile Matter
   Sulfur, wt %,  as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total

Weight, g
   Initial
   Treated
Weight Loss,  %
   Of Total Weight
   Of Coal Weight

 Reduced Data
   (100 Ib Coal Originally)
   Weight,  Ib
   Sulfur Weight, Ib, as
       Sulfide
       Sulfate
       Pyritic
       Organic
         Total

    Sulfur Content, wt%, as
       Sulfide
       Sulfate
       Pyritic
       Organic
         Total

    Wt % Original Sulfur Removed
       From Feed
                                                             TB-50
                                                  Pretreated W. Kentucky No. 9
                                                                20
                                                              1500
                                                                15
                                                     Feed
                                                     0.04
                                                     0.06
                                                     0.96
                                                     0.43
                                                     1.49
                                                     4.1714
                                                   256.62
 Float
 0.36
 0.06
 0.40
 0.47
 1.29
Sink
0.96
0.14
0.02
0.22
1.34
 0.9013   2.7903

      11.95
      35.86
62.62   194.00
0.11
0.16
2.45
1. 10
3782
0.23
0.04
0.25
0.29
oTsT
1.86
0.27
0.04
0.43
2760
                                                               0. 40
                                                               0.47
                                                               0.87
                                                               85.9
                       9,  20°F/min, 1500°F)  (Continued)


                        	TB-56	
                        Pretreated W. Kentucky No.  9
                                      20
                                    1500
                                       0
                                                                                         Feed
0.04
0.06
0.96
0.43
1.49
                          3.7436
              256.62
                                    Float    Sink
0.25
0.00
0.04
0.72
1.01
0. 30
0.08
0.00
0. 32
0.70
                                                                                                  0.9515
                                   2.3225
                                                                                                       12.78
                                                                                                       38.33
        65.05
       158.77
0.11
0. 16
2.45
1. 10
3.82
0. 16
0.00
0.03
0.47
0756
0.47
0. 13
0.00
0.51
T7TT
                                  86.91

-------
         TABLE 37.   THERMOBALANCE RUN DATA  (PRETREATED WESTERN KENTUCKY  NO. 9,  20°F/min,  1500°F)  (Continued)
VO
00
Run No.
Coal Type
Heating Rate, "F/min
Terminal Temperature,  °F
Holding Time,  min

Lab Analysis, wt %
   H20
   Volatile Matter
   Sulfur, wt %,  as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total

Weight, g
   Initial
   Treated
Weight Loss, %
   Of Total Weight
   Of Coal Weight

Reduced Data
   (100 Ib Coal Originally)
   Weight, Ib
   Sulfur Weight, Ib,  as
      Sulfide
      Sulfate
      Pyritic
      Organic
        Total

   Sulfur Content, wt%, as
     Sulfide
     Sulfate
     Pyritic
     Organic
        Total

   Wt % Original Sulfur Removed
     From Feed
                                                                TB-55
                             TB-40
                                                     Pretreated W. Kentucky No.  9   Pretreated W.  Kentucky No.  9
                                                                   20                            20
                                                                 1500                          1500
                                                                    0                             0
                                                        Feed
                                                        4.5487
                                                      256.62
 Float
  Sink
Feed
Float
Sink
0.04
0.06
0.96
0.43
1.49
0.22
0.00
0. 56
0.39
1. 17
0.69
0.07
0.00
0.33
1.09
0.04
0.06
0.96
0.43
1.49
0. 34
0.00
0.33
0.37
1.04
1. 18
0.05
0.03
0.28
1.54
                    4.5438
 0.7746    2.4618

     10.30
     30.89
55. 11
175.18   256.62
                     1.0533    3.0353

                          13.27
                          39.81
         57.34   165.23
0. 11
0. 16
2.45
1. 10
3.82
0. 12
0.00
0.31
0.21
0.64
1.18
0.12
0.00
0.56
1.86
0.11
0. 16
2.45
1. 10
3.82
0. 19
0.00
0. 19
0.22
0.60
1.95
0.08
0.05
0.46
2.54
                                                                  0.56
                                                                  0. 39
                                                                  0.95
                                                                 86. 4
                              0.33
                              0. 37
                              0.70
                             80. 3
                                                                                                     D75123021

-------
                           TABLE 38.   THERMOBALANCE RUN DATA (PRETREATED WESTERN KENTUCKY  NO.  9,  1300 F)
v£>
                                                      W. Kentucky No. 9
                                                             750
                                                      Coal  Pretreated Coal
Run No.                          Pretreatment
Coal
Heating Rate, °F/min
Terminal Temperature, ° I
Holding Time, min
Lab Analysis, wt %
   H20
   Volatile Matter
   Sulfur, wt %,  as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total
 Weight, g
   Initial                   100.00
   Treated
 Weight Loss, %
   Of Total Weight
   Of Coal Weight
 Reduced Data
   (100 Ib Coal in Feed)
    Weight, Ib               100. 00
    Sulfur Weight, Ib, as
       Sulfide
       Sulfate
       Pyritic
       Organic
          Total
 Sulfur Content, wt %, as
 s  Sulfide
    Sulfate
    Pyritic
    Organic
       Total
  Wt % Original Sulfur Removed
    From Feed
                                                                                       TB-39
                                                                                                                TB-38
Pretreated W. Ky. No.  9
          5
        1300
          0
 Feed    +50     -50
                                         Pretreated W. Ky.  No. 9
                                                    5
                                                  1300
                                                    0
                                          Feed    Float    Sink
5.9
33.4
0. 00
0. 07
2. 30
0. 97
3. 34
1
. 8









32. 3
0.
0.
2.
1.
4.
13
19
87
29
48
0.
0.
0.
0.
1.
04
06
96
43
49
0. 30
0.00
0. 53
0.47
1.30
0.
0.
0.
0.
1.
69
10
00
47
26
0.
0.
0.
0.
1.
04
06
96
43
49
0. 00
0. 00
0. 88
0. 24
1. 12
0.62
0. 08
0.02
0.42
1. 14
85. 54

14.46
14.46
                                                                85. 54
4.4626                    4.6853
        0. 9832  2. 9246

             11.68
             35. 03


256.62   57.02  169.63     256.62
                                  0.9805  3.2105

                                       12. 19
                                       36.56


                                   52.72  172.62
0.00
0. 07
2. 30
0. 97
3. 34
0. 00
0. 07
2. 30
0. 97
3. 34
0.
0.
2.
1.
3.


2.

4.
11
16
45
10
82


87
12
16
0.
0.
2.
1.
3.





11
16
45
10
82





0.17
0. 00
0. 30
0. 27
0.74


0. 53
0.47
1. 00
1.
0.
0.
0.
2.





17
17
00
80
14





0.
0.
2.
1.
3.





11
16
45
10
82





0.00
0. 00
0.46
0. 13
0. 59


0. 88
0.24
1. 12
1.07
0. 14
0.03
0. 73
1.97





                                                                                         71.8
                                   68.5

-------
                  TABLE  38.   THERMOBALANCE RUN DATA  (PRETREATED  WESTERN  KENTUCKY NO.  9,  1300°F)  (Continued)
O
O
 Run No.
 Coal
 Heating Rate, ° F/min
 Terminal Temperature, ° F
 Holding Time, min
 Lab Analysis, wt %
    H2O
    Volatile Matter
    Sulfur, wt %,  as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total
 Weight, g
    Initial
    Treated
 Weight Loss, %
    Of Total Weight
    Of Coal Weight
 Reduced Data
    (100 Ib Coal in Feed)
    Weight, Ib
    Sulfur Weight, Ib, as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total
 Sulfur Content, wt %, as
s   Sulfide
    Sulfate
    Pyritic
                                                                         TB-48
                                                                                                   TB-49
                                       Total
                                  Wt % Original Sulfur Removed
                                     From Feed
Pretreated W. Ky. No. 9
5
1300
0
Feed Float Sink
0.04 0.20 0.91
0.06 0.00 0.05
0.96 0.56 0.13
0.43 0.33 0.12
1.49 1.09 1.21
4. 3008
0.8317 2.9358
12. 30
36. 91
256.62 49.69 175.36
0.11 0.10 1.60
0.16 0.00 0.09
2.45 0.28 0.23
1.10 0.16 0.21
3.82 0.54 2.13
0. 56
0.33
0.89
88. 5
Pretreated W. Ky.



Feed
0.04
0.06
0. 96
0.43
1.49
4. 1520



256.62
0.11
0.16
Z. 45
1.10
3.82




5
1300
30
Float
0.24
0.00
0. 56
0. 58
1.38

0. 8177
11.
35.
50. 37
0. 12
0.00
0. 28
0. 29
0.69
0.56
0.58
1.14
85.1
No. 9



Sink
0.61
0.12
0.06
0.31
1.10

2. 8498
98
95

- 1.07
0.21
0.11
0. 54
1.93




B75123074

-------
TABLE  39.  THERMOBALANGE RUN DATA  (PRETREATED WESTERN  KENTUCKY NO.  9, 1600°F)
    Run No.
    Coal Type

    Heating Rate, °F/min
    Terminal Temperature, °:
    Holding Time, min
    Lab Analysis,  wt %
       H2O
       Volatile Matter
       Sulfur, wt %, as
          Sulfide
          Sulfate
          Pyritic
          Organic
             Total
    Weight,  g
       Initial
        Treated
    Weight Loss, %
       Of Total Weight
       Of Coal Weight
    Reduced Data
       (100 Ib Coal Originally)  100. 00
       Weight, Ib
       Sulfur Weight, Ib,  as
          Sulfide
          Sulfate
          Pyritic
          Organic
             Total
       Sulfur Content,  wt %, as
          Sulfide
          Sulfate
          Pyritic
          Organic
             Total
       Wt % Original Sulfur Removed
          From Feed
Pretreatment
TB-41
Western Kentucky No. 9

7min

Coal
5.9
33.4
0.00
0. 07
2. 30
0. 97
3. 34
100. 00


100. 00
0.00
0. 07
2. 30
0. 97
3.34
s
0. 00
0.07
2. 30
0. 97
3.34

750

Pretreated Coal
1.8
32. 3
0. 13
0. 19
2. 87
1.29
4.48
85. 54
14.46
14.46
85. 54
0. 11
0. 16
2.45
1. 10
3.82

2.87
1.29
4. 16
Pretreated
Western Kentucky No. 9
20
1600
30
Feed Float


0.04 0.37
0.06 0.00
0.96 0.11
0.43 0.54
1.49 1.02
3.6476
0.6887
14
43
256.62 48.00
0.11 0.18
0. 16 0. 00
2.45 0.05
1.10 0.26
3.82 0.49

0.11
0. 54
0.65



Sink

,
1.38
0.03
0.02
0.18
1.61
2.4628
.40
.19
171.67
2.37
0.05
0.03
0.31
2.76


                              81.7
                                     A75123022
                                         101

-------
    UJ
    cr
    u.
       6.0
       5.0
       4.0
       3.0
       2.0
        1.0
A  FLOAT, NO HOLD
V  FLOAT, 30-MIN. HOLD
D +50, NO HOLD

O +50, 30-MIN. HOLD

O  PRETREATED COAL
          600     800     1000     1200    1400
                           TEMPERATURE, F°
                  1600
                                                A75I22920
1800
Figure 31.  Thermobalance char-sulfur content at 5  F/min heating rate.

-------
UJ
H-

O
O

CC
ID
   5.0
   4.0
    3.0
2.0
    1.0
      0
O
D
V
O
                        I
                       FLOAT,20°F/min,30-min HOLD
                       FLOAT, IO°F/m in, 30-min HOLD
                       FLOAT, 20°F/min , NO HOLD
                       PRETREATED COAL
                             I
                 I
I
      600     800    1000     1200    1400

                         TEMPERATURE, °F
                                           1600     I8OO
                                                    A7707I722
  Figure 32.  Thermobalance char-sulfur content at 10  and 20 F/min

             heating rates.

-------
      A quantity  of  the  coal was pretreated in the same way as the Western
 Kentucky No.  9.   Results  of the pretreatment and Run TB-67 are presented in
 Table 40.   Weight losses  are  in the range expected  (10% to 15%).  The sulfur
 content of  the treated  coal was also low, comparable to the treated Midwestern
 coal.  However,  the feedstock was not pretreated adequately (compared with the
 Western Kentucky coal treated at the same condition) and the sample caked in
 the thermobalance test.   Therefore, the sulfur content is not indicative of
 values that might be experienced if the coal were properly pretreated.

      The pretreated material  was subjected to a second air treatment, and
 thermobalance runs  were made.  The second pretreatment reduced the volatile
 content, but  the coal still caked in all thermobalance tests.  These data
 indicate that this  sample of  Pittsburgh seam coal is more agglomerating than
 the Western Kentucky coal.

      Runs TB-68  to  TB-70,  in  Table 41, were made with the double pretreated
 coal.  All  these tests  were heated at 5°F/min to 1500°F.  Run TB-69 had a 30-
 minute holding time and nitrogen was used for the initial heat-up to 700°F
 and then hydrogen to the  run's end at 1500°F.  The  coal used for Run TB-70 was
 ground to —80 mesh  before mixing.  Sulfur reduction is good in Runs TB-68 and
 TB-69 despite the caking.  The low recovery and high-sulfur content of the
 residue in  Run TB-70 make obtaining the fine material unfeasible with these
 operating conditions.

      A new  sample of raw  coal was screened and severely pretreated.  The coal
 was heated  to 750°F with  air  and held at this temperature for 1 hour.  Weight
 loss, including  moisture,  was over 18%.  The volatile matter content was re-
 duced to about 25%  in the final material.  This degree of pretreatment was
 sufficient  because  the  treated coal did not cake in subsequent testing.

      Thermobalance  test Runs  TB-71 and TB-75, Table 42, were made with this
 pretreated  coal.  Both were heated at 5°F/min to 1500°F with no holding.  Run
 TB-71 was mixed  with lime in  the usual ratio; TB-75 used coal only.  This coal,
 however,  does not separate into float-sink portions as readily as the Western
 Kentucky No.  9;  more of the coal goes into the sink portion.  The sulfur con-
 tent  of the treated coal  has  been reduced near to the levels expected at these
 conditions  based on past  experience with Western Kentucky coal.

      The pretreatment for the above tests was severe.  To determine  if less
 treatment would  have sufficed, some coal was pretreated at less severe con-
 ditions — shorter time  at  750 F.

      The pretreated material  was then used for Runs TB-72 to TB-74,  presented
 in  Table 43.  Runs  TB-73  and  TB-74 were heated at 5°F/min to 1500°F  with no
 holding.  Run TB-73 was mixed with lime, while TB-74 was coal only.   Both
 residues showed  slight agglomeration, making the separation difficult.  The
 sulfur  was  significantly  reduced in both tests.  Apparently, the  lime is
 desirable because Run TB-74 shows a higher sulfur content; these  results may,
however, be masked  by poorer  separation.

      In Run TB-72,  a rapid heat-up procedure was used.  The reactor  was heated
to 1500°F and the basket was  lowered into the heated zone.  A large  temperature


                                     104

-------
        TABLE 40.   THERMOBALANCE RUN  DATA (PRETREATED PITTSBURGH
                      SEAM, W. VA.,  1500°F,  0 min)
Run No.
                             Pretreatment
                                                       TB-67
Coal Type Pittsburgh Seam, W. Va. Pretreated Pittsburgh
Heating Rate, °F/min
Terminal Temperature, °F
Holding Time, min
Lab Analysis, wt °'o
H2O
Volatile Matter
Sulfur, wt °~o, as
Sulfide
Sulfate
Pyritic
Organic
Total
Weight, g
Initial
Treated
Weight Loss, <%
Of Total Weight
Of Coal Weight
Reduced Data
(100 Ib Coal in Feed)
Weight, Ib
Sulfur Weight, Ib, as
Sulfide
Sulfate
Pyritic
Organic
Total
Sulfur Content, wt #>, as
Sulfide
Sulfate
Pyritic
Organic
Total



Coal
7. 7
33. 8

0. 00
0. 05
1. 4Q
1. ?7
2. 91
100. 00


100. 00
0. 00
0. 05
1.49
1 37
2. 91

0. 00
0. 05
1.49
1. 37
2.91
Wt <, Original Sulfur Removed
From Feed
Wt "a Original Sulfur Removed
From Original Coal

750

Pretreated Coal Feed
1. 2
•»3. 0

0. OP 0.03
0. 10 0. 03
1.24 0.41
1.42 0.47
2.85 0.94
4. 7900
85.64
14. 36
14. 36

85.64 256.92
0.08 0.08
0.08 0.08
1.05 1.05
1.20 1.20
2.41 2.41


1.24
1.42
2.66
22.68
5
1500
0
Float
--
--

0. 29
0. 06
0. 02
0.45
0. 82
1.2970
13.
41.

69. 57
0. 20
0.04
0.01
0. 31
0. 56


0.02
0.45
0.47
86.7
89.0
1
Seam, W. Va.



Sink
--
--

0.42
0. 12
0. 00
0. 16
0.70
2.8236
97
92

151.46
0.64
0.18
0.00
0.24
1.06



5-114-2072
                                   105

-------
      TABLE 41.   THERMOBALANCE RUN DATA  (DOUBLE PRETREATED  PITTSBURGH
                             SEAM, W.  VA.,  1500°F)
Run No.
Coal Type
Heating Rate, °F/min
Terminal Temperature, °F
Holding Time, min
Lab Analysis, wt %
   H2O
   Volatile Matter
   Sulfur, wt fo,  as
      Sulfide
      Sulfate
      Pyritic
      Organic
        Total
Weight, g
   Initial
   Treated
Weight Loss, %
   Of Total Weight
   Of Coal Weight
Reduced Data
   (100 Ib Coal in Feed)
   Weight, Ib
   Sulfur Wt,  Ib, as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total
Sulfur Content, wt %,  as
   Sulfide
   Sulfate
   Pyritic
   Organic
      Total
Wt ^o Original Sulfur Removed
   From Feed
Wt % Original Sulfur Removed
   From Original Coal

 *—80 mesh.
  Double Pretreatment
                            TB-68
Pittsburgh Seam,  W. Va.
          750
   Coal  Pretreated Coal
 100. 00
83. 92
              Pretreated Pittsburgh Seam, W. Va.
                              5
                             1500
                              0
                   Feed     Float      Sink
7.7
33.8
0.
0.
1.
1.
2.
00
05
49
37
91
1
. 1

--

--

--
32.0
0.
0.
1.
1.
3.
10
12
37
41
00
0.
0.
0.
0.
1.
03
04
46
47
00
0.
0.
0.
0.
0.
21
04
02
53
80
0.
0.
0.
0.
0.
42
07
01
09
59
                               5.0814
                                         1.2166
                                      3.1563
                                                t3. 94
                                                41. 83
251.76
60. 28
156. 38
0.00
0. 05
1.49
1.37
2.91
0.00
0.05
1.49
1.37
2.91


0. 08
0. 10
1. 15
1.18
2. 51
0. 10
0.12
1.37
1.41
3.00


0.08 0.13
0.10 0.02
1.15 0.01
1.18 0.32
2.51 0.48


0.02
0.53
0.55
86.9
88.7
0.66
0.11
0.02
0.14
0. 92







                                         106

-------
TABLE 41.   THEKMOBALANCE RUN DATA  (DOUBLE PRETREATED PITTSBURGH
                   SEAM,  W. VA., 150Q°F)  (Continued)
       Run No.
       Coal Type
       Heating Rate, ?F/min
       Terminal Temperature,  °F
       Holding Time, rnin
       Lab Analysis, wt  %
          H20
          Volatile Matter
          Sulfur, wt %, as
            Sulfide
            Sulfate
            Pyritic
            Organic
               Total
       Weight, g
          Initial
          Treated
       Weight Loss, %
          Of Total Weight
          Of Coal Weight
       Reduced Data
          (100 Ib Coal in Feed)
          Weight, Ib
          Sulfur Wt, Ib,  as
             Sulfide
             Sulfate
             Pyritic
             Organic
                Total
       Sulfur Content, wt %, as
          Sulfide
          Sulfate
          Pyritic
          Organic
              Total
        Wt ^  Original  Sulfur Removed
           From Feed
        Wt %  Original  Sulfur Removed
           From Original Coal

        *—80 mesh.
           TB-69
•Pretreated Pittsburgh Seam.  W. Va.
               5
              1500
               30
     Feed     Float       Sink
0.03
0.04
0.46
0.47
1.00
0.30
0.00
0.02
0. 52
0.84
0.60
0.03
0.00
0.16
0. 79
   4.9956
   251. 76

     0.08
     0.10
     1.15
     1.18
     2.51
            0.9817
         3.3146
                   14.00 .
                   42.00
50.49

 0. 15
 0.00
 0.01
 0.26
 0.42
              0.02
              0. 52
              0.54

              89.3
              90.7
170.46

  1.02
  0.05
  0.00
  0.27
  1.34
                                        107

-------
TABLE 41.   THERMOBALANCE  RUN  DATA  (DOUBLE PRETREATED PITTSBURGH
                SEAM,  W.  VA.,  1500°F)  (Continued)
      Run No.                         	TB-70	
      Coal Type
      Heating Rate, ?F/min
      Terminal Temperature,  °F
      Holding Time, min
      Lab Analysis, wt  %
         H2O
         Volatile Matter
         Sulfur^ wt %, as
            Sulfide
            Sulfate
            Pyritic
            Organic
              Total
      Weight, g
         Initial
         Treated
      Weight  Loss, %
         Of Total Weight
         Of Coal Weight
      Reduced Data
         (100 Ib Coal in  Feed)
         Weight,  Ib
         Sulfur Wt, Ib, as
            Sulfide
            Sulfate
            Pyritic
            Organic
              Total
      Sulfur Content,  wt %,  as
         Sulfide
         Sulfate
         Pyritic
         Organic
            Total
      Wt °fo Original Sulfur Removed
         From Feed
      Wt % Original Sulfur Removed
         From Original Coal

      #—80 mesh.
Pretreated Pittsburgh Searn^ W. Va. *
                  5
                 1510
                   0
     Feed
     0.03
     0.04
     0.46
     0.47
     1.10

   4.7065
   251.76

     0.08
     0.10
     1.15
     1..18
     2. 51
                 Float
  0.00
  0. 28
  0.03
  1.40
  1.71
           Sink
0.36
0.08
0.01
0.30
0.75
0.1079   3.8968

       14. 91
       44.73


  5.77   245.99
  0.00
  0.02
  0.00
  0.08
  0.10
                 0.03
                 1.40
                 1.43
0.88
0.20
0.02
0.74
1.84
                  96.8
                  97. 3
                       B-114-2071
                                     108

-------
TABLE  42.   THERMOBALANCE  RUN DATA  (PRETREATED PITTSBURGH SEAM, W.  VA.,  1500 F,  0  min)
Run No.
Coal Type
Heating Rate, ?F/rmn
Terminal Temperature, °F
Holding Time, min
Lab Analysis, wt "<,
H20
Volatile Matter
Sulfur, wt %, as
Sulfide
Sulfate
Pyritic
Organic
Total
Weight, g
Initial
Treated
Weight Loss, °t.
Of Total Weight
Of Coal Weight
Reduced Data
(100 Ib Coal in Feed)
Weight, Ib
Sulfur Weight, Ib, as
Sulfide
Sulfate
Pyritic
Organic
Total
Sulfur Content, wt.%, as
Sulfide
Sulfate
Pyritic
Organic
Total
Wt "t Original Sulfur Removed
From Feed
Wt % Original Sulfur Removed
From Original Coal
*No lime.
Pretreatment
Pittsburgh seam.W. Va.

750

Coal Pretreated Coal
7.7 1.0
33. 8 24. 8

0.00 0.16
0.05 0.46
1.49 0.95
1.37 '.66
2.91 3.23

100.00
81.81

18. 19
18. 19


100.00 81.81

0.00 0.13
0.05 0.38
1.49 0.78
1.37 1.36
2.91 2.65

--
--
0. 95
1.66
2.61

26.46
26.46

                                                	TB-71	
                                                 Pretreated Pittsburgh seam,W. Va.
                                                               5
                                                              1500
                                                               0
                                                Feed         Float           Sink
                                                0.05
                                                0. 15
                                                0. 32
                                                0. 55
                                                1.07

                                              5. 0400
                                               245.43

                                                0. 13
                                                0. 38
                                                0.78
                                                1.36
                                                2.65
 0. Z3
 0.00
 0.01
 0.65
 0.89
                                                            0.6271
30. 54

 0.07
 0.00
 0.00
 0. 20
 0. 27
                                                              0.01
                                                              0.65
                                                              0.66

                                                             92.45

                                                             93. 13
  0.46
  0. 10
  0.01
  0. 27
  0.84
             3.7766
                                                                   12.63-
                                                                   37.89 •
  0.85
  0. 18
  0.02
  0. 50
  1. 55
                       	TB-75*	
                       Pretreated Pittsburgh Seam,  W. Va.
                                      5
                                    1500
                                      0
                       Feed         Float         Sink
 0. 16
 0.46
 0.95
 1.66
 3.23

 2.7784
183.89   81.81
0. 13
0.38
0.78
1.36
2.65
  0.57
  0.04
  0.03
  0.72
  1.36
42.83

 0.24
 0.02
 0.01
 0.31
 0.58
                                  0.03
                                  0.72
                                  0.75

                                 87.92
                                 89.00
  3.73
  0.07
  0.04
  0.46
  4.30
                                                                                                      27.49
16.48

 0.61
 0.01
 0.01
 0.08
 0.71
                                                                                                         B75123017

-------
TABLE 43.  THERMOBALANCE RUN DATA (PRETREATED PITTSBURGH SEAM, W. VA.)
 1XU.11 1NO.
                              Pre treatment
                                                           TB-7Z
Coal Type Pittsburgh Seam, W. Va. Pretreated Pittsburgh Seam, W. Va.
Heating Rate, °F/min
Terminal Temperature, °F
Holding Time, min
Lab Analysis, wt °'a Coal
H20 7.7
Volatile Matter 33. 8
Sulfur, wt ",, as
Sulfide 0.00
Sulfate 0.05
Pyritic 1 . 49
Organic 1.37
Total 2.91
Weight, g
Initial 100.00
Treated
Weight Loss, »*»
Of Total Weight
Of Coal Weight
Reduced Data
(100 Ib Coal in Feed)
Weight, Ib 100. 00
Sulfur Weight, Ib, as
Sulfide 0.00
Sulfate o.05
Pyritic j 49
Organic j. 37
Total 2.91
Sulfur Content, wt ""a, as
Sulfide
Sulfate
Pyritic
Organic
Total
Wt "", Original Sulfur Removed
From Feed
Wt "i Original Sulfur Removed
From Original Coal

750

Pretreated Coal Feed
0. 6
31. 6

0.04 0.01
0.10 0.03
1.27 0.42
1. 56 0. 52
2.97 0.98

4. 5112
88. 80

11. 20
11.20


88.80 266.40

0.04 0.04
0.09 0.09
1.13 1.13
1.39 1.39
2.65 2.65



1.27
1. 56
2. 83

13.40
13.40
Rapid
1500
60
Float Sink



0.62 0.65
0.00 0.00
0.01
0. 35 0. 18
0.84


3. 8209

15. 30
45.90


9.10 216.54

0.06 1.41
0.00 0.00
0.02
0.03 0.39
1.8E








  No lime.
                                 110

-------
TABLE  43.   THERMOBALANCE  RUN DATA  (PRETREATED PITTSBURGH SEAM,  W.  VA.)  (Continued)
     1VU11 1NU.
     Coal Type
     Heating Rate.  °F/min
     Terminal Temperature, °F
     Holding Time, min
     Lab Analysis, wt °'a
       H20
       Volatile Matter
       Sulfur, wt ",,  as
          Sulfide
          Sulfate
          Pyritic
          Organic
             Total
     Weight,  g
       Initial
       Treated
     Weight Loss, "<,
       Of Total Weight
       Of Coal Weight
     Reduced Data
       (100 Ib Coal in Feed)
       Weight,  Ib
       Sulfur Weight, Ib, as
          Sulfide
          Sulfate
          Pyritic
          Organic
             Total
     Sulfur Content, wt #,, as
       Sulfide
       Sulfate
       Pyritic
       Organic
          Total
     Wt "*, Original Sulfur Remove'!
       From Feed
     Wt <*o Original Sulfur Removed
       From Original Coal
     No lime.
                                                   TB-73
                                                                                        TB-74
 Pretreated Pittsburgh Seam, W. Va.
                 5
               1500
                 0
 Feed         Float         Sink
  4.7455
266. 40
Pretreated Pittsburgh Seam, W. Va,
              5
             1500
              0
Feed         Float        Sink
0.01
0.03
0.42
0. 52
0.98
0. 32
0.02
0. 00
0. 51
0. 85
0. 48
0.05
0.01
0.09
0. 63
0.04
0. 10
1.27
1.56
Z.97
0. 15
0.01
0.03
0. 89
1.08
0. 80
0.06
0.06
0.70
1.62
                                       3. 5142
                    4. 0378

                      14.91
                      44.74
              80.48
                           146.20
                                      88. 80
                0.00
                0.51
                0.51

               84. 53
               85.91
                                                          2.3601
                     32.84
                                                   32. 81
                                                                26.83
0.04
0.09
1. 13
1 39
2.65
0.26
0.02
0.00
0.41
0.69
0.70
0.07
0.01
0. 13
0.91
0.04
0.09
1. 13
1. 39
2.65
0.05
0.00
0.01
0.29
0. 35
0.21
0.02
0.02
0. 19
0.44
              0.03
              0.89
              0.92

             88.68
             89.68
                                                                                           B75020186
                                                       111

-------
 gradient  was  imposed and a rapid heat-up was achieved.  The sample was left
 for 1 hour  and  then removed.  These conditions proved to be too rapid in
 heat-up and the sample was badly agglomerated.  Complete analysis of the data
 was impossible.

      Satisfactory  sulfur content can be achieved by treatment of this coal;
 however,  not  enough data have been obtained to draw definitive conclusions as
 to sulfur removal.  Pretreatment must be with longer residence and/or more
 air than  with the  Midwestern coals, resulting in higher weight loss in
 pretreatment.

      The  degree, or severity, of pretreatment differs for each coal.  Some coals
 require only  slight pretreatment and have relatively low weight loss.  Others
 require more  treatment and have higher weight loss.

      The  Western Kentucky No. 9 coal could be pretreated at 750°F with 1 SCF
 02/lb of  coal being consumed in 30 minutes.  This is representative of the
 conditions  necessary for pretreatment of coals from the Illinois Basin and
 results in  about 10% weight loss.  Coals such as the Pittsburgh seam require
 750°F temperature  with 2 SCF 02/lb of coal and from 30 minutes to 1 hour
 residence time.  Weight loss for this treatment is usually 15% or more.

      Each seam  or  mine may have its own characteristics such that pretreatment
 conditions  are  different for each.

 BATCH REACTOR TESTS - WESTERN KENTUCKY NO. 9

      The  modified  batch reactor described earlier was used to test the desul-
 furization  concept in a fluidized-bed reactor.  Information was taken from
 thermobalance runs to aid in establishing operating conditions for the unit.
 The fluidized-bed  arrangement was expected to enhance gas-particle contact
 and increase  sulfur removal.  The feed coal, whether pretreated or not, was
 screened  to —20+40 mesh and, when mixed, was 2 parts coal to 1 part lime of
—60+80 mesh.

      The  first  tests in the batch reactor were with nonpretreated Western
Kentucky  No.  9  coal.  Table 44 lists the results of these tests.  The heating
rate  was  5°F/min to 900°F, except Run BR-74-3 was heated to 1350°F.  All tests
were  held at  their terminal temperatures for 30 minutes.  A high hydrogen  rate
was used  to simulate the gas flow conditions used in the pilot-unit.  This
flow  was  too  high  for the smaller unit, and excessive bed elutriation resulted.
Some  sulfur reduction in the residue took place, but this may be the result  of
concentrating the  lime portion by flushing out the higher-sulfur-bearing coal
fraction.

      Later  batch reactor runs were made with pretreated Western Kentucky No. 9
coal.   To reduce entrainment losses, the hydrogen flow rate was reduced to
yield a bed velocity of 0.35 ft/s at 900°F and 0.5 ft/s at 1500°F.

     Runs BR-74-4 and BR-74-5, in Table 45, were made with the usual mixture
of feedstock materials.  Both tests were heated to 900°F at 5°F/min and held
                                     112

-------
               TABLE  44.   BATCH  REACTOR RUN  DATA  (WESTERN KENTUCKY  NO. 9)
Run No.
Coal Type
Heating Rate,  °F/min
Terminal Temperature,  '
Holding Time,  min

Lab Analysis, wt %
   H2O
   Volatile Matter
   Sulfur, wt %,  as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total

Weight,  g
   Initial
   Treated
Weight Loss, %
   Of Total Weight
   Of Coal Weight

 Reduced Data
   (100  Ib Coal in Feed)
   Weight,  Ib
   Sulfur Weight, Ib, as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total

    Sulfur Content,  wt %, as
      Sulfide
      Sulfate
      Pyritic
       Organic
         Total
Coal
W.Ky. No. 9
Coal
5.9
33.4
0.00
0.07
2.30
0.97
3.34
BR-74-1
W. Kentucky No. 9
5
900
30
Feed Residue
0.00 0.77
0.07 0.11
2.30 1.69
0.97 1.04
3.34 3.61
                                      BR-74-2
                                                  BR-74-3
100.00
100.00

  0.00
  0.07
  2.30
  0.97
  3.34
  0.00
  0.07
  Z. 30
  0.97
  3.34
200.00
                    158.00

                     21.00
                     21.00
100.00    79.00
  0.00
  0.07
  2.30
  0. 97
  3. 34
  0.00
  0. 07
  2. 30
  0.97
  3. 34
0.61
0.09
1. 34
0. 82
2. 86
1.69
1.04
2.73
                                 W. Kentucky No. 9
                                         5
                                       900
                                        30

                                   Feed   Residue
                                            0. 40
                                            0.04
                                            0. 16
                                            0. 16
                                            0.76
                               167.00

                                16.50
                                49. 50
           300.00    250.50
                       0.00
                       0.02
                       0.77
                       0.32
                       1. 11
           200.00
0.00
0.07
2.30
0.97
3. 34
0.00
0.07
2. 30
0.97
3.34
1.00
0. 10
0.40
0. 40
1.90
0.79
0.79
1.58
                                             W. Kentucky No. 9
                                                      5
                                                   1350
                                                     30
                                              Feed
                                   0.00
                                   0.02
                                   0.77
                                   0.32
                                   1.11
                    200.00
300.00

  0,00
  0. 07
  2. 30
  0.97
  3. 34
  0.00
  0. 07
  2. 30
  0.97
  3. 34
                                            Residue
                                 0. 17
                                 0.04
                                 0.08
                                 0.13
                                 0. 42
110.00

 45.00




165.00

  0.28
  0. 07
  0. 13
  0.21
  0. 69
    Wt % Original Sulfur Removed
       From Feed
       From Original Coal
                     35.3
                     35.3
                               76.0
                               76.0
                                                                                             A75123024

-------
             TABLE 45.  BATCH REACTOR  RUN DATA  (PRETREATED WESTERN KENTUCKY  NO.  9, 900°F)
Run No.
Coal Type
Heating Rate, °F/min
Terminal Temperature,
Holding Time,  min

Lab Analysis, wt %
   H2O
   Volatile Matter
   Sulfur, wt %,  as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total
Weight, g
   Initial                      100.00
   Treated
Weight Loss,  %
   Of Total Weight
   Of Coal Weight

Reduced Data
   (100 Ib Coal in Feed)
   Weight, Ib                 100.00
   Sulfur Weight,  Ib,  as
      Sulfide
      Sulfate
      Pyritic
      Organic
        Total
   Sulfur Content, wt %, as
      Sulfide
      Sulfate
      Pyritic
      Organic
        Total

   Wt % Original Sulfur Removed
       From Feed
Pretreatment
          BR-74-4
                                                       BR-74-5
W. Kentucky No. 9 Pretreated W. Kentucky No. 9 Pretreated W. Kentucky No. 9
5 5
750 900 900
30 30
Pretreated
Coal Coal Feed +50 - 50 Feed Residue
5.9
33.4
0.00
0.07
2.30
0.97
3.34
1. »
3Z.3
0.13
0.19
2.87
1.29
4.48


0.04
0.06
0.96
0.43
1.49


0.80
0.07
0.36
1.06
2.29


0.49
0.03
0.19
0.03
0.74


0.13
0. 19
2.87
1.29
4.48


0.86
0.06
0.49
1.17
2.58
      85.54

      14.46
      14.46
      85.54
                150.00
                                 100.00
           38.00
           97.00
                 10.00
                 30.00
256,62
65.01
165.95
0.00
0.07
2.30
0.97
3.34
0.11
0.16
2.45
1.10
3.82
0. 11
0. 16
2,45
1.10
3.82
0.52
0.05
0.23
0.69
1.49
0.81
0.05
0.32
0.05
1.23
0.00
0.07
2.30
0.97
3.34


2.87
1.29
4.16
0. 11
0.16
2.45
1.10
3.82


0.36
1.06
1.42
85.54

 0.11
 0.16
 2.45
 1.10
 3.82
                                                   0.11
                                                   0.16
                                                   2.45
                                                   1.10
                                                   3.82
                           75.9
                        85.00

                        15.00
                        15.00
72.71

 0.63
 0.04
 0.36
 0.85
 1.88
                                              0.49
                                              1.17
                                              1.66
                                             68.3

                                        A75123023

-------
 for  30 minutes at the terminal temperature.  Sulfur reduction was similar to
 the  thermobalance tests at these conditions.
 i-H         ^ P^8Sf tS run* hfted at 5°F/mln to 1500°F, with only Run BR-74-10
 being  held 30 minutes at the final temperature.  The treated samples from Runs
 BR-74-9  and BR-74-10 were riffled into two parts, and then each part was
 screened or float-sink separated.  The treated coal fractions show sulfur levels
 slightly higher than those from the thermobalance tests at this temperature
 Weight losses from the batch reactor runs are higher, but the increased loss
 was  probably caused by fluidization losses.

     A lower terminal temperature, 1300°F, was used in Runs BR-74-8 and BR-74-
 11,  shown in Table 47.  Both tests were heated at 5°F/min, and Run BR-74-11
 was  held for 30 minutes at 1300°F.  High material losses made the results from
 Run  BR-74-8 inconclusive; however, Run BR-74-11 shows the percentage sulfur
 removal  in the higher end of the range of values experienced in the 1500°F
 tests.

   Q  Table 48 lists data for Runs BR-74-12 and BR-74-13, heated to 1500°F at
 10  and  20°F/min.   No holding time was used in either test.  The sulfur values
 are  comparable to  the batch reactor tests heated at 5°F/min with no holding,
 but  are  still higher than the thermobalance tests at the same condition.
 Further  sulfur reduction may be possible by holding at the terminal temperature
 after  using the higher heat-up rates.

     Two runs, BR-74-18 and BR-74-19 (coal only), were exposed to a rapid heat-
 up to  1500°F,  with Run BR-74-19 being held for 30 minutes (Table 49).   The
 rapid  heat-up is accomplished by turning full power to the heaters until the
 target temperature is reached.  A rate of 65° to 70°F/min is possible by this
 procedure.   Weight losses are lower than those usually found at 1500°F  because
 of the shorter reaction time.  Run BR-74-19 has the highest weight loss and
 lowest sulfur content as expected.  Although the sulfur reduction has not been
 reduced  to levels  usually associated with these temperatures at lower heating
 rates, the data are promising.  Run BR-74-19, held at 1500°F for 30 minutes,
 shows  considerably lower sulfur content than Run BR-74-18.  This indicates that
 rapid  heat-up with much longer holding times may be as beneficial as lower
 heat -up  rates.

     The results of the batch reactor tests using pretreated Western Kentucky
 No. 9  coal are presented graphically in Figure 33.   Total sulfur has been
 reduced  significantly from the pretreated coal to the hydrogen-treated  coal.
 Removal  of  sulfide and sulfate further depress the curve.   The differences
 between  1300°  and  1500°F are less than in the thermobalance tests and are
 probably due to better contact between gas and particles.   Comparing Figure 33
 with Figure 31,  the overall sulfur level at 1500°F treatment is not as  satis-
 factory  in  the batch reactor tests.   Perhaps the much higher relative hydrogen
 flows  in the thermobalance tend to release the "fixed" organic sulfur.

 BATCH REACTOR  TESTS - PITTSBURGH SEAM, WEST VIRGINIA

     Four runs,  BR-74-14 to BR-74-17,  shown in Table 50, were made with
Pittsburgh  seam coal.   Caking was evident in all of these tests, indicating


                                      115

-------
              TABLE  46.   BATCH  REACTOR RUN  DATA (PRETREATED WESTERN KENTUCKY NO.  9, 1500 F)
Run No.
Coal Type
Heating Rate, "F/min
Terminal Temperature,
Holding Time,  min

Lab Analysis, wt %
   HZO
   Volatile Matter
   Sulfur, wt %, as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total
Weight, g
   Initial                      150.00
   Treated
Weight Loss %
   Of Total Weight
   Of Coal Weight

Reduced Data
   (100  Ib Coal Originally)
   Weight, Ib                 100.00
   Sulfur Weight,  Ib, as
      Sulfide
      Sulfate
      Pyritic
      Organic
        Total

   Sulfur Content, wt %,  as
      Sulfide
      Sulfate
      Pyritic
      Organic
        Total

   Wt % Original Sulfur Removed
      From Feed
   Pretreatment
W. Kentucky No.  9

       750
                   BR-74-6
  3.34
  0.00
  0.07
  2.30
  0^97
  3.34
         Pretreated W. Kentucky No. 9

                     1500
                        0
                                         BR-74-7
                                Pretreated W. Kentucky No. 9
                                              5
                                           1500
                                              0
Pretreated
Coal Coal
5.9
33.4
0.00
0.07
2. 30
0.97
3.34
1.8
32.3
0.13
0.19
2.87
1.29
4.48
Feed
0.04
0.06
0.96
0.43
1.49
+ 50
0.22
0.03
0.40
0.04
0.69
- 50
0.88
0.09
0. 14
0.04
1.15
Feed
0.04
0.06
0.96
0.43
1.49
Float
0.09
0.00
0.68
0.14
0.91
Sink
0.77
0.19
0.02
0.38
1.36
           85.54

           14.46
           14.46
           85.54
3.82
                    150.00
                    27. 50
                    96.00
                                          150.00
                         17.67
                         53.00
         256.62
         47.05
         164.20
          256.62
3.82
0.32
                     0.40
                     0^04
                     0.44
                               94. 5
1.89
3.82
                                 22:04
                                 96,86
                                                 20.73
                                                 62.20
          37.71
         165.71
0.00
0.07
2.30
0.97
0.11
0.16
2.45
1.10
0.11
0.16
2.45
1.10
0. 10
0.01
0. 19
0.02
1.44
0. 15
0.23
0.07
0.11
0. 16
2.45
1.10
0.03
0.00
0.26
0.05
0.75
0.18
0.02
0.37
0.34
                                            0.68
                                            0.14
                                            0.82
                                                      91.88
1.32

-------
     TABLE 46.  BATCH REACTOR RUN  DATA (PRETREATED WESTERN KENTUCKY NO.  9,  1500°F)  (Continued)
                         Feed
                          1.49
                        150.00
Run No.
Coal Type
Heating Rate, "F/min
Terminal Temperature,  "I
Holding Time,  min

Lab Analysis, wt %
   H2O
   Volatile Matter
   Sulfur, wt %,  as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total

Weight,  g
   Initial
   Treated
Weight Loss  %
   Of Total Weight
   Of Coal Weight

Reduced Data
   (100  Ib Coal Originally)
   Weight, Ib
   Sulfur Weight,  Ib, as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total

   Sulfur Content,  wt %,  as
      Sulfide
      Sulfate
      Pyritic
      Organic
         Total
Wt «!» Original Sulfur Removed
   From Feed
                        Z56. 62
                                           BR-74-9
                                  Pretreated W. Kentucky No. 9
                                                5
                                             1500
                                                0
                                                                                              BR-74-10
                                                 Pretreated W. Kentucky No.  9
                                                               5
                                                            1500
                                                              30
Float
Sink
50
- 50
Feed
Float
                               Sink
                                                + 50
 0.91
1.44
                                                        0.92
                              '1.74
                   1.49
                                                                           150.00
                     0.83
                    1.47
                                                0.83
f 	
••-11. -1 -1 	 •
93.99 . ,
                                                                                                     14.73
47.44    128.78
                                                       38.56    137.66
                                       256.62
                                       51.39   167.38
                                     0.31
                                     0.48
                                     0.79
                                        90.0
                     0.51
                     0.20
                     0.71
                                                           92.7
                                       0. 52
                                       0. 15
                                       0.67
                                                 90. 80
                                                                                - 50
0.04
0.06
0.96
0.43
0. 12
0.00
0.31
0.48
0.74
0. 19
0.05
0.46
0.20
0.01
0.51
0.20
1.18
0.10
0.05
0.41
0.04
0.06
0.96
0.43
0.14
0.02
0. 52
0. 15
1.02
0. 12
0.02
0.31
0.21
0.00
0.39
0.23
1. 34
0.09
0.02
0. 31
                              1.76
                                              59.25    159.52
0. 11
0.16
2.45
1.10
3.82
0.06
0.00
0. 15
0.23
0.44
0.95
0.24
0.06
0. 59
1. 84
0.08
0.00
0.20
0.08
0.36
1.62
0. 14
0.07
0.56
2.39
0. 11
0. 16
2.45
1. 10
3.82
0.07
0. 01
0.27
0.08
'.43
1.71
0.20
0.03
0. 52
2.46
0. 12
0.00
0.23
0. 14
0.49
2. 14
0. 14
0.03
0.49
2. 80
                                               0. 39
                                               0.23
                                               OT6T
                                                                    90. 31

                                                                        D75123030

-------
                  TABLE 47.   BATCH REACTOR RUN  DATA  (PRETREATED WESTERN KENTUCKY  NO. 9,  1300°F)
00
  Pretreatment
W. Kentucky No. 9

      750
P retreated
Coal
33.' 4
0.00
0.07
2.30
0.97
3.34
Coal

0.13
0. 19
2.87
1.29
4.48
Feed

0.04
0.06
0.96
0.43
1.49
+ 50

0. 18
0.01
0. 34
0. 51
1.04
- 50

1.01
0.10
0.00
0.42
1.53
               Run No.
               Coal Type
               Heating Rate, °F/min
               Terminal Temperature,
               Holding Time, min

               Lab Analysis, wt %
                 H20
                 Volatile Matter
                 Sulfur,  wt %, as
                    Sulfide
                    Sulfate
                    Pyritic
                    Organic
                       Total
Weight, g
   Initial                      100.00              150.00
   Treated                               85.54
Weight Loss,  %
   Of Total Weight                       14.46          «-
   Of Coal Weight                        14.46          <-

Reduced Data
   (100 Ib Coal Originally)
   Weight, Ib                 100.00     85.54     256.62
   Sulfur Weight, Ib,  as
      Sulfide
      Sulfate
      Pyritic
      Organic                   	     	       	
        Total                  3. 34     3.82       3.82

   Sulfur Content, wt %, as
      Sulfide                    0.00                0.11
      Sulfate                    0.07                0.16
      Pyritic                    2.30     2.87       2.45
      Organic                   0.97     1.29       1.10
        Total                  3.34     4.16       3.82

   Wt % Original Sulfur Removed
      From Feed
          BR-74-8
Pretreated W. Kentucky No.  9
               5
            1300
               0
                                                       Float
                                                                           43.39
                                                                            0.45
                                                                            0.34
                                                                            0.51
                                                                            0.85
                                                                           90. 3
                                                                                            -33.00-
                                                                                            -99.00
                                         128.53
0.00
0.07
2.30
0.97
0.11
0.16
2.45
1.10
0.11
0.16
2.45
1.10
0.08
0.00
0.15
0.22
1.30
0.13
0.00
0.54
                      42.47
                                           1.97
                                  Sink
                                                                  0.73
                                                                  0.08
                                                                  0.04
                                                                  0.39
                                                                  1.24
129.46
                                                      88.5

-------
TABLE 47.   BATCH REACTOR RUN DATA (PRETREATED WESTERN KENTUCKY  NO. 9,
                                     1300°F)
                                 (Continued)
          Run No.
          Coal Type
          Heating Rate, °F/min
          Terminal Temperature, °F
          Holding Time, min

           Lab Analysis, wt %
              H2O
              Volatile Matter
              Sulfur, wt %, as
                Sulfide
                Sulfate
                Pyritic
                Organic
                   Total

           Weight, g
              Initial
              Treated
           Weight Loss, %
              Of Total Weight
              Of Coal Weight

           Reduced Data
              (100 Ib Coal Originally)
              Weight, Ib
              Sulfur Weight, Ib,  as
                 Sulfide
                 Sulfate
                 Pyritic
                 Organic
                    Total

              Sulfur Content, wt %, as
                 Sulfide
                 Sulfate
                  Pyritic
                  Organic
                    Total

               Wt % Original Sulfur Removed
                  From Feed
                       BR-74-11
  Feed
150.00
256.62

  0.11
  0.16
  2.45
  1.10
  3.82
  0.11
  0.16
  2.45
  1.10
  3.82
             Pretreated W. Kentucky No.  9
                            5
                         1300
                           30
 + 50
52.00
 0.44
 0.33
 0.77
             89.5
  - 50
 Float
168.02
48.80
           0.62
           0.25
           0.87
                     89.0
Sink
0.23
0.02
0.44
0.33
1.02
0.94
0.13
0.04
0.52
1763
0.12
0.02
0.62
0.25
1.01
0.64
0.23
0.04
0.50
1.41
t 	
42.78
-">
                              171.22
0.12
0.01
0.23
0.17
0.53
1.58
0.22
0.07
0.87
2.74
0.06
0.01
0.30
0.12
0.49
1.10
0.39
0.07
0.86
2.42
                                                                                    B75123029

-------
                TABLE  48.  BATCH REACTOR RUN DATA (PRETREATED WESTERN KENTUCKY NO.  9,  10° and  20°F/min)
S3
o
            Run No.
            Coal Type
            Heating Rate,  °F/min
            Terminal Temperature,
            Holding Time,  min

            Lab Analysis,  wt %
               H2O
               Volatile Matter
               Sulfur, wt %, as
                 Sulfide
                 Sulfate
                 Pyritic
                 Organic
                    Total
Weight, g
   Initial                       100.00
   Treated
Weight Loss,  %
   Of Total Weight
   Of Coal Weight

Reduced Data
   (100 Ib Coal Originally)
   Weight, Ib                  100.00
   Sulfur Weight,  Ib, as
      Sulfide
      Sulfate
      Pyritic
      Organic
        Total

   Sulfur Content, wt %,  as
      Sulfide                    0.00
      Sulfate                    0.07
      Pyritic                    2. 30
      Organic                   0.97
        Total                   3. 34

   Wt % Original Sulfur Removed
      From Feed
   Pretreatment
W. Kentucky No. 9

      750
                                BR-74-12
                      Pretreated W. Kentucky No. 9
                                   10
                                 1500
                                 -   0
Pretreated
Coal
5.9
33.4
0.00
0.07
2.30
0.97
3. 34
Coal
1.8
32.3
0.15
0.19
2.87
1.29
4.48
Feed


0.04
0.06
0.96
0.43
1.49
+ 50


0.23
0.01
0.43
0.32
0.99
- 50


1.06
0.04
0.01
0.34
1.45
Float


0. 11
0.03
0.40
0.31
0.85
Sink


0. 54
0.21
0.05
0.49
1.29
85.54

14.46
14.46
                                                     85.54
                                                               150.00
                                                                                           •18.47
                                                                                           •55.42
256.62
                     59.78
                                        149.44
45.61
                                                                          88.2
                                                                                                  0.40
                                                                                                  0.31
                                                                                                  0.71
                                            91.6
163.61
0.00
0.07
2. 30
0.97
3. 34
0. 11
0. 16
2.45
1. 10
3.82
0.11
0. 16
2.45
1. 10
3. 82
0. 14
0.01
0.26
0. 19
0. 60
1.58
0.06
0.01
0. 51
2.16
0.05
0.01
0. 18
0. 14
0.38
0.88
0.34
0.08
0.80
2. 10

-------
TABLE  48.
BATCH  REACTOR  RUN DATA  (PRETREATED WESTERN  KENTUCKY NO.  9, 10°  and 20°F/min) (Continued)
        Run No.
        Coal Type
        Heating Rate,  °F/min
        Terminal Temperature,  °F
        Holding Time,  min

        Lab Analysis, wt %
           H2O
           Volatile Matter
           Sulfur, wt %, as
              Sulfide
              Sulfate
              Pyritic
              Organic
                 Total

        Weight,  g
           Initial
           Treated
        Weight Loss,  %
           Of Total Weight
           Of Coal Weight

        Reduced Data
           (100  Ib Coal Originally)
           Weight,  Ib
           Sulfur Weight,  Ib, as
              Sulfide
              Sulfate
              Pyritic
              Organic
                 Total
                                                      BR-74-13
                                 Feed
                                 0.04
                                 0.06
                                 0.96
                                 0.43
                                 1.49
                               150.00
                               256.62

                                 0. 11
                                 0.16
                                 2.45
                                 1. 10
                                 3.82
                                            Pretreated W. Kentucky No.  9
                                                         20
                                                      1500
                                                         0
 + 50
 0.23
 0.01
 0.06
 0.79
 1.09
57.24
  - 50
Float
                                                            -17.33-
                                                            •52.09-
212.14
                     43.06
Sink
0.86
0. 17
0.00
0.23
1.26
0. 14
0.02
0.05
0.75
0.96
0.37
0. 15
0.00
0.38
0.90
         169.08
0.13
0.01
0.03
0.45
0.62
1.82
0.36
0.00
0.49
2. 67
0.06
0.01
0.02
0.32
0.41
0.63
0.25
0.00
0.64
1.52
            Sulfur Content,  wt %, as
               Sulfide
               Sulfate
               Pyritic
               Organic
                 Total

            Wt % Original Sulfur Removed
               From Feed
                                             0.06
                                             0.79
                                             0.85
                                            87.43
                      0.05
                      0.75
                      0.80
                     91.1
                                                                                    B75123028

-------
 TABLE 49.   BATCH REACTOR  RUN  DATA  (PRETREATED WESTERN  KENTUCKY NO. 9  RAPID HEATUP)
Run No.
Coal Type
Heating, Rate, ?F/min
Terminal Temperature, °F
Holding Time, min
Lab Analysis, wt %
H2O
Volatile Matter
Sulfur, wt %, as
Sulfide
Sulfate
Pyritic
Organic
Total
Weight, g
Initial
Treated
Weight Loss, %
Of Total Weight
Of Coal Weight
Reduced Data
(100 Ib Coal in Feed)
Weight, Ib
Sulfur Weight, Ib, as
Sulfide
Sulfate
Pyritic
Organic
Total
Sulfur Content, wt %, as
Sulfide
Sulfate
Pyritic
Organic
Total
Wt *><, Original Sulfur Removed
Pretreatment
W.



Coal
5.9
33.4

0.00
0.07
2. 30
0.97
3.34

100.00






100.00

0.00
0.07
2. 30
0.97
3.34







Ky. No. 9



Pretreated Coal
1. 8
32.3

0. 13
0. 19
2.87
1.29
4.48


85.54

14.46
14.46


85.54

0. 11
0. 16
2.45
1. 10
3.82



2.87
1.29
4.16

                                                       	BR-74-18	
                                                       Pretreated W. Ky. No. 9
                                                               Rapid
                                                               1500
                                                                 0
                                                       Feed             Residue
                                                       0. 13
                                                       0. 19
                                                       2. 87
                                                       1.29
                                                       4.48

                                                     150.00
                                                      85.54

                                                       0. 11
                                                       0. 16
                                                       2.45
                                                       I. 10
                                                       3.82
From Feed
  0.98
  0.06
  0. 19
  1.47
  2.70
105.00

 30.00
 30.00


 59. 88

  0.58
  0.04
  0. 11
  0. 88
  1.61
                                                                           0. 19
                                                                           1.47
                                                                           1.66

                                                                          76.96
                         BR-74-19	
                  Pretreated W. Ky. No.  9
                         Rapid
                         1500
                          30
                  Feed             Residue
  0. 13
  0. 19
  2. 87
  1.29
  4.48

150.00
 85.54

  0. 11
  0. 16
  2.45
  1. 10
  3. 82
 1.41
 0.03
 0.06
 1.06
 2.56
93.00

38.00
38.00


53.03

 0.75
 0.02
 0.03
 0.56
 1.36
                                    0.06
                                    1.06
                                    1. 12

                                   84.55

                               B75020188
 No lime.

-------
to
                         5.0
                         4.0
                         3.0
5  2.0
                          1.0
                                         O RAPID HEAT-UP
                                         A FLOAT
                                         D +50
                                         V PRETREATED COAL
                           ^\ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^JL^^^^^^^^^j^^^j^^^^^^^^^^^^
                           600     800     1000     1200     1400     1600     1800

                                             TEMPERATURE, °F
                                                                             A75I229I9
                                Figure 33.  Batch reactor  char-sulfur content.

-------
                 TABLE 50.   BATCH  REACTOR RUN DATA  (PRETREATED PITTSBURGH SEAM, W. VA.)
Run No.
Coal Type
Heating Rate,  °F/min
Terminal Temperature,  °F
Holding Time,  min
Lab Analysis,  wt %
    H20
    Volatile Matter
    Sulfur, wt %, as
        Sulfide
        Sulfate
        Pyritic
        Organic
            Total
Weight, g
    Initial
    Treated
Weight Loss, %
    Of Total Weight
    Of Coal Weight
Reduced Data
    (100 Ib Coal in Feed)
    Weight, Ib
    Sulfur Wt,  Ib, as
        Sulfide
        Sulfate
        Pyritic
        Organic
            Total
Sulfur Content, wt %,  as
    Sulfide
    Sulfate
    Pyritic
    Organic
        Total               2.91
Wt % Original  Sulfur Removed
  From Feed
Wt % Original  Sulfur Removed
  From Original Coal
Pretreatment
Pittsburgh seam, W. Va
750
Coal Pretreated Coal
7.7
33.8
0.00
0.05
1.49
1.37
2.91
100.00

100.00
0.00
0.05
1.49
1.37
2.91
0.00
0.05
1.49
1.37
1.2
33.0
0.09
0.10
1.24
1.42
2.85
85.64
14.36
14.36
85.64
0.08
0.08
1.05
1.20
2.41
1.24
1.42
      BR-74-14
       2.66
      22.68
                        Pretreated Pittsburgh seam,  W.  Va.
                                        5
                                      1500
                                        0
                        Feed     +50     -50    Float    Sink
0.03
0.03
0.41
0.47
0.94
150.00






256.92
0.08
0.08
1.05
1.20
2.41


0.38
0.06
0.02
0.41
0.87







97.93
0.37
0.06
0.02
0.40
0.85
0.02
0.41
0.61
0.11
0.02
0.06
0.80

126.60 -
15.60 -
46.80 -
118.91
0.73
0.13
0.02
0.07
0.95


0.29
0.00
0.00
0.73
1.02







52.63
0.15
0.00
0.00
0.38
0.53
0.00
0.73
0.58
0.09
0.04
0.38
1.09







164.21
0.95
0.15
0.07
0.62
1.79


 0.43

82.57

85.57
 0.73

84.23

86.94

-------
               TABLE 50.   BATCH REACTOR RUN DATA (PRETREATED PITTSBURGH SEAM, W. VA.) (Continued)
ui
Run No.
Coal Type
Heating Rate, °F/min
Terminal Temperature,  °F
Holding Time, min
Lab Analysis, wt %           Feed
    H2°
    Volatile Matter
    Sulfur, wt  %, as
        Sulfide             0.03
        Sulfate             0.03
        Pyritic             0.41
        Organic             0.47
             Total           0.94
 Weight,  g
     Initial               150.00
     Treated               	
 Weight Loss, %
     Of Total Weight       	
     Of Coal Weight        	
 Reduced Data
      (100 Ib Coal in Feed)
     Weight, Ib
      Sulfur Wt, Ib, as
          Sulfide             0.08
          Sulfate             0.08
          Pyritic             1.05
          Organic             1.20
             Total           2.41
  Sulfur Content, wt %, as
      Sulfide
      Sulfate
      Pyritic
      Organic
          Total
  Wt % Original  Sulfur  Removed
    From Feed
  Wt % Original  Sulfur  Removed
    From Original  Coal
                                              BR-74-15
                                                         BR-74-16
                                 Pretreated Pittsburgh
                                                  5
                                                1500
                                                 30
                                         +50
0.38
0.04
0.01
0.40
0.83
256.92   90.50
0.34
0.04
0.01
0.36
0.75
                                        0.01
                                        0.40
                                        0.41
                                        84.65
                                        87.28
                        seam, W. Va.
                         Float   Sink
0.71
0.07
0.01
0.17
0.96
1 ?fi fifi
i A fin
J_O . UU
AR nn
125.31
0.89
0.09
0.01
0.21
1.20





0.19
0.13
0.02
0.50
0.84



42.38
0.08
0.06
0.01
0.21
0.36
0.02
0.50
0.52
90.87
92.44
0.59
0.09
0.01
0.23
0.92



173.43
1.02
0.16
0.02
0.40
1.60





                                    Pretreated Pittsburgh seam, W. Va.
                                                    5
                                                  1500
                                                    0
                                  Feed     +50     —50    Float   Sink
                                                                          0.03
                                                                          0.03
                                                                          0.41
                                                                          0.47
                                                                          0.94
                                                                          0.08
                                                                          0.08
                                                                          1.05
                                                                          1.20
                                                                          2.41
                                                   0.23
                                                   0.05
                                                   0.01
                                                   0.66
                                                   0.95
                                                                        256.92   97.79
                                                   0.22
                                                   0.05
                                                   0.01
                                                   0.65
                                                   0.93
                                                   0.01
                                                   0.66
                                                   0.67

                                                  72.60

                                                  77.32
0.48
0.04
0.01
0.32
0.85
120.30 -
19.8 -
59.4 -
108.26
0.52
0.04
0.01
0.35
0.92





0.19
0.02
0.00
0.84
1.05






56.78
0.11
0.01
0.00
0.48
0.60
0.00
0.84
0.84
80.08
83.51
0.44
0.10
0.01
0.37
0.92






149.27
0.66
0.15
0.01
0.55
1.37






-------
        TABLE 50.  BATCH REACTOR RUN DATA (PRETREATED PITTSBURGH SEAM, W. VA.)  (Continued)
Run No.
Coal Type
Heating Rate, °F/min
Terminal Temperature, °F
Holding Time, min
Lab Analysis, wt%
    HO
    Volatile Matter
    Sulfur, wt %, as
        Sulfide
        Sulfate
        Pyritic
        Organic
            Total
Weight, g
    Initial
    Treated
Weight Loss, %
    Of Total Weight
    Of Coal Weight
Reduced Data
    (100 Ib Coal in Feed)
    Weight, Ib
    Sulfur Wt, Ib, as
        Sulfide
        Sulfate
        Pyritic
        Organic
            Total
Sulfur Content, wt %, as
    Sulfide
    Sulfate
    Pyritic
    Organic
        Total
Wt % Original Sulfur Removed
  From Feed
Wt % Original Sulfur Removed
  From Original Coal

*No lime in this test.
             BR-74-17*
Pretreated Pittsburgh seam, W. Va.
                   5
                 1500
                   0
   Feed                 Treated  Coal
   0.09
   0.10
   1.24
   1.42
   2.85

 150.00
  85.64

   0.08
   0.08
   1.05
   1.20
   2.41
 0.72
 0.05
 0.09
 1.05
 1.91
                          103.00

                           31.33
                           31.33
58.81

 0.42
 0.03
 0.05
 0.62
 1.12
                            0.09
                            1.05
                            1.14

                           72.20

                           76.98

-------
the coal had not  been fully pretreated.  Screen separation showed more +50
material recovered than initially charged.  Lime has evidently been trapped
by the caked coal particles and increased the weight of the +50 fraction
Because of  this dilution with lime, the coal fraction appears to have a lower
percentage  of  sulfur.   The float portions of the first three tests show low
sulfur but, again, this may be due to incomplete separation.   Run BR-74-17
was made with  coal only and, although the coal was badly caked,  sulfur was
still reduced  to  1.14% in the final residue calculation.  With the proper
pretreatment,  avoiding caking, it is expected that the sulfur can be reduced
to levels comparable to Western Kentucky No. 9 coal.

GAS SAMPLE  ANALYSIS

Batch Reactor

     Analyses  for batch reactor off-gas, on an air-free basis, are shown in
Table 51.   These  data were taken from grab samples collected  during the peak
temperature period of the run.  While not identical to the gas concentrations
expected from  a continuous operation, the species and distribution should be
generally indicative of the off-gas to be obtained from a continuous unit.
The t^S is  derived from reaction with coal sulfur, while the  longer-chain
molecules can  be  attributed to devolatilization.

Pilot Reactor  Runs

     Pilot  reactor off-gas sample analyses are shown in Table 52.  All of these
runs were made at temperatures of 1200°F or lower.  The gases containing sulfur
are quite varied  and many are devolatilization products only, caused by the
lower operating temperature.  No H^S was detected in any of the  samples and
sulfur balances could not be made for these runs.   Hydrogen sulfide is assumed
to be lost  to  adsorption by the reactor and sample container or  to condensation
between sampling  and analysis.

Modified Batch Reactor

     Gas sample analyses for the modified batch reactor are shown  in Tables
53 through  58.  Tables 53 through 55 are for pretreated Western  Kentucky No. 9
coal and Tables 56 through 58 are for pretreated  Pittsburgh seam,  West
Virginia coal.  For these data, grab samples were collected while  the reactor
was being heated;  samples were taken when possible at temperatures of 800 ,
1200°, and  1500°F.

     Table  53  lists off-gas constituents at a reactor temperature  of 800°F.
The ea<9  as exoected,  is mostly hydrogen with some carbon species  from the
S£l?  No sulfur  compounds were detected in the gas samples for  the first four
tests.  The reason for this effect is unknown;  perhaps the Ime  was effectively
removing the sulfur-containing gases at the time  the sample was  taken.  The
runs in which  sulfur was detected show several species, but no H2S.

     In Table  54,  the  analyses are shown for samples taken at  1200°F.  These
show generally higher  values for the carbon species.   However, the amounts of
                                      127

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                            TABLE 51.  BATCH REACTOR GAS ANALYSIS - ILLINOIS NO. 6 COAL
              No.                                 14         16        18        19        20
         Mass Spectrometer Analysis,
           mol %
              Nitrogen                         10.85        5.3      16.3      16.7      24.0
              Carbon Monoxide                              0. 1                          0. 04
              Carbon Dioxide                                        0. 02
              Hydrogen                         88.75       94.3      83.5      83.1      76.0
              Methane                                       0.1      0.13      0.16
              Ethane                                                0. 03
              Propane                                               0.01
              n- Butane                                              0. 02
£             Ethyl ene                                               0.01
oo
              Propylene                                             0.01
              Toluene                                      0. 14
              Argon                             0. 40       0. 06
         Chroma tograph Analysis, ppm
              Hydrogen Sulfide                   15.0                15.2      18.6      63.0
              Carbonyl Sulfide                    0.7                 1.9       0.5       0.9
              Methyl Mercaptan                                       1. 3
              Ethyl Mercaptan                   11.9        2.2       6.3       2.2       3.4
              Thiophene                                              2. 4       0. 7
              Dimethyl Disulfide                  0.3                 0. 7       0.4
             t^Amyl Mercaptan                                     10. 5       1.0
             Methylethyl Disulfide                1.1                28.5
              C6 to C8 Sulfides

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                           TABLE  52.   PILOT REACTOR GAS ANALYSIS - ILLINOIS NO.  6  COAL

    Run No.                      VII     VIII A   VIII B    IX A    IX B    IX C       X      XI      XII A    XII B
    Mass Spectrometer
     Analysis, mol %
       Nitrogen
       Carbon Monoxide
       Carbon Dioxide
       Hydrogen
       Methane
       Ethane
M      > Cz
to
vO
     Chromatograph Analysis,
      ppm
        Carbonyl Sulfide
        Ethyl Mercaptan
        n-Propyl Mercaptan
        Thiophene
        Dimethyl Disulfide
        Methylethyl Disulfide
        Diethyl Disulfide
        C5H12S
        ^6^148
        > C6H14S
1.65 1.95
1.77 1.61
0.16 0.03
93.85 95.40
1.77 0.59
0.19 0.05
0.61 0.37










1.72 3.13
1.60 2.19
0.03 0.17
94.72 91.06
1.11 2.51
0.17 0.27
0.65 0.67
1. 1
0.4

4. 5
1.6
1.1
1. 5
13.8
14.6
6.5
2. 53
2.07
0.03
93. 55
1. 27
0. 14
0.41
2.7
2.6
1. 1
10.7
2.1
1.2
5.2
38.9
67. 5
62.7
1.03
1.84
0.01
95.52
1.15
0.09
0. 36
2.5
2.6
1. 2
9.0
4.6
4.5
6.4
34.8
67.7
114.4
1.3
2. 5
0.09
91.5
4.0
0. 21
0.40
1.5
0.9
0.4
9.3
0.3
0.3
2.6
28. 1
41.7
81.4
1. 5
1.8
0.03
93.4
2.2
0.29
0.78
3.6
4.7
1.6
17.7
8. 7
2.7

43. 9
28. 7
8. 1
1.81 2.09
2.17 2.56
0.34 0.03
92.40 9L29
2.65 2.79
0.18 0.41
0.45 0.83











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     TABLE 53.   MODIFIED BATCH REACTOR GAS ANALYSIS (800°F) - PRETREATED WESTERN KENTUCKY NO. 9 COAL

Run. No.
Mass Spectrometer Analysis, mol %
   Nitrogen
   Carbon Monoxide
   Carbon Dioxide
   Hydrogen
   Methane
   Ethane

Chromatograph Analysis, ppm
   Carbonyl Sulfide
   Carbon Bisulfide
   Dimethyl Sulfide
   Thiophene
   Dimethyl Disulfide
                                      BR-74-7   BR-74-8   BR-74-9   BR-74-11   BR-74-12   BR-74-13
0. 5


99.0
0.4
0. 1
*







0.9 1.0 0.1
0.1 0.1 0.1
0.3
99.8 99.0 98.5 99.6
0.1 0. 1 0.1 0.2

* * *
1.0
3. 5

1.6
53.0
4.6
4. 5



99.9
0.1


1.6
0.9
1.6
2.8
2.2
11.9
8.9
"No sulfur detected.

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   TABLE 54.  MODIFIED BATCH REACTOR GAS ANALYSIS  (1200°F) - PRETREATED WESTERN KENTUCKY NO.  9 COAL
Run No.

Mass Spectrometer Analysis, mol %
   Nitrogen
   Carbon Monoxide
   Carbon Dioxide
   Hydrogen
   Methane

Chromatograph Analysis, ppm
   Carbonyl Sulfide
   Carbon Bisulfide
   Thiophene
                                          BR-74-7
BR-74-8
BR-74-11
BR-74-13
2.0
0.1
0.6
96.8
0.5

1.0
1.0

0.3 1.6
0.2 0.2
0.4
98.7 97.4
0.8 0.4
*
2.0
0.2
0.4
1.3
0.6
0.2
97. 2
0.7

1.6
0.4

No sulfur detected.

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                        TABLE 55.   MODIFIED BATCH REACTOR OFF-GAS  ANALYSIS (1500°F) -
                                   PRETREATED WESTERN KENTUCKY NO.  9  COAL
              Run No.                                    BR-74-7             BR-74-13

              Mass Spectrometer Analysis, mol %
                 Nitrogen                                  0. 7                   0. 3
                 Carbon Monoxide                          0. 2                   0. 3
                 Carbon Dioxide                            0. 1
                 Hydrogen                                  98. 5                  98.6
,_,                Methane                                   0. 5                   0.8
NJ
              Chromatograph Analysis, ppm
                 Carbonyl Sulfide                           0. 5                   1.9
                 Carbon Disulfide                          0.7                   0.7

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                           TABLE 56.  MODIFIED  BATCH REACTOR OFF-GAS (800 F) -
                                PRETREATED PITTSBURGH SEAM (W. VA.) COAL
OJ
u>
Run No.

Mass Spectrometer Analysis,  mol
   Nitrogen
   Carbon Monoxide
   Carbon Dioxide
   Hydrogen
   Methane

 Chromatograph Analysis, ppm
    Carbonyl Sulfide
    Carbon Bisulfide
    Thiophene
                                                      BR-74-14
 3.0

 0.3
96.6
 0.1
 1.0
 1.8
             BR-74-15
                                                                       1.6
             BR-74-16
                                                                       1,3
                                                                       1.0
                                                                                     0.4
                                                                                    99.5
 0. 5
97.8
 0. 1           0. 1
               660
                95
                12
               100

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              TABLE 57.  MODIFIED BATCH REACTOR OFF-GAS (1200°F)
                    PRETREATED PITTSBURGH SEAM (W. VA.) COAL
Run No.                                  BR-74-14     BR-74-15     BR-74-16

Mass Spectrometer Analysis, mol %
   Nitrogen                                0.8            2.4
   Carbon Monoxide                                                    0. 3
   Hydrogen                              99. 0           97. 2           99.4
   Methane                                0. 2            0.4            0.3

Chromatograph Analysis, ppm                             *             *
   Carbon Bisulfide                        0.6
     sulfur detected.

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             TABLE 58.  MODIFIED BATCH REACTOR OFF-GAS (1500°F) -
                   PRETREATED PITTSBURGH SEAM (W. VA.) COAL

                                                                       BR-74-15
Run No.                                  BR-74-14      BR-74-15   (15 min into holding)

Mass Spectrometer Analysis, mol %
   Nitrogen                                2.6            0.4              1.4
   Carbon Monoxide                                      0.5              0.4
   Carbon Dioxide                         0. 3                             0. 1
   Hydrogen                              96. 9           98. 7             97. 9
   Methane                                0.2            0.4              0.2

 Chromatograph Analysis, ppm
    Carbonyl Sulfide                        0. 7            0. 5              2. 3
    Carbon Disulfide                                      1.5              0. 9
    Thiophene                                                              3. 8
    C5H12S                                                0.8              1.8

-------
 sulfur gases are lower than in the same tests at 800°F.  This effect may be
 due  to reduced devolatilization at the higher temperature.

     Analyses of gas samples at 1500 F are shown in Table 55.  These are only
 slightly different than the 1200°F analyses and show very low sulfur content.

     Table 56 shows analyses for off-gases at 800°F of the pretreated
 Pittsburgh seam, West Virginia coal.  All analyses are typical except the
 sulfur types in BR-74-16.  This test shows much higher values than any other
 tests and the results are unexplained.

     Analyses of gases at 1200°F are shown in Table 57.  Only a small amount
 of sulfur was detected in BR-74-14 and none was detected in the other two
 samples.

     Table 58 shows analyses for gases at 1500°F.  Once again, there are few
 sulfur-bearing gases and they are low in value.

     The sampling and analysis of sulfur-bearing gases was inadequate for
 these tests.  While balances can be made for the other coal constituents, it
 was  not possible to make a sulfur balance for any of the runs.  This is
 possibly caused by the reactivity of some of the species with their environment.
 The  cooling of the sample between sampling and analysis may also be part of
 the  problem.  Future work must take these effects into account; a more complete
 analysis is required.

 CONCLUSIONS

     A pretreatment step is required for coals of the Midwestern and Eastern
 seams.  This prevents agglomeration and caking in subsequent treatment for
 sulfur removal.  The pretreatment also seems of benefit in removing sulfur.

     Analysis of the hydrodesulfurization test results shows that with proper
 conditions of time, temperature, heating rate, etc., a substantial sulfur
 reduction is achieved.  This is true for all the coals tested to date.  Some
 coals require more severe conditions because of their original sulfur content
 or the seam location.

     Use of lime as an acceptor may not be as beneficial as originally antici-
pated.   While runs made with lime show less sulfur in the coal residue, there
 is also less residue recovered and some carbon loss to the lime fraction.

     Gas analysis shows some heating value is available from the hydrocarbons
present.

     Further work is required before conclusively determining conditions  for
treatment of each coal, its final sulfur content, or the characteristics  of
the gaseous or any other stream from the process.
                                     136

-------
                                PROCESS CONCEPT


     A process concept  flow sheet,  incorporating the results from the thermo-
balance and batch reactor  runs  for  the Western Kentucky No. 9 coal, is presented
in Figure 34.  Streams  not characterized have not yet been studied in the
program.  The data presented on Figure 34 are tentative; they are taken from an
analysis of thermobalance  and batch reactor tests that generate only small
samples and are batch-type,  not continuous as the process would be.  The pilot
unit, with a continuous feed and discharge system, will generate larger samples
and better material and energy  balances.

     The process, as  it is now  conceived, yields a solid fuel meeting Federal
EPA standards for direct combustion (1.2 Ib S02/million Btu).  The fuel con-
tains 50% by weight of  the input coal and 60% of the original carbon.  Heat
energy would be available  from  gas, tars, and oils generated both in the pre-
treater and hydrotreater.   Carbon and hydrocarbon values in the lime would be
used as a heat source for  regeneration.   Elemental sulfur would be a by-product.
                                       137

-------
u>
00
GASES
Ib
H20 114.7
C 70.1
H 25.4
S 9.5 PRETREATEO
0 270.5 COAL
N 1000. 1 |b
|H20 14.1
ASH 296.0
C 1199.0
H 62.2


GASES
Ib
HaO 14,1
C 305.7
H 382.2
S 15.9
0 104.7
N 9.9
COa 23.3
S bb.B
0 IZ2.2
PRETREATER N 25.2 ,™D™^
SIZED COAL 750°F
Ib
H?0 118.0
ASH 296.0 I
C 1269 1 T L
H 876 1 ">
S 76.3 AIR ASH 3207-2
0 127.0 15 i- I3D
N 26-° H20^01 £ 442|
0 265.7 0 Z72 8
N 999.3 N 0.4
C02 23.6
BASIS: 1 TON W. KENTUCKY COAL
(As Received)
linn«F MIXED RESIDUE

i
r
L
Ib
^— ^— fltn ^sm ^
C 881.9
H 24.6
S 53.9
0 207.7
N 15.6
C02 113.9
t
MAKEUP
LIME
1 |
HYDRO-
ZATION

SEPARATION

LIME
REGENERATION



	 ^- CONDENSER

TREATED COAL
Ib
ASH 206.4
C 762.1
H 13.6
0 .1
N 11.3 .

SPENT LIME
Ib sin
ASH 3296.8 REM(
C 119.8
H 11.0
S 4B.4 	
0 206.6
N 4.3
CO 113.9 '
_^ GAS
CONVERSION
i
COOLING
TOWER
r
*
SEPARATOR

TARS
AND
OILS
™ — ^ SULFUR
BY-PRODUCT
GAS
H2
MAKEUP HYDROGEN — ^ ^GENERATION
                                                                                              B-74-II48
                               Figure 34.  Flow sheet for proposed process.

-------
                                  FUTURE WORK
NECESSITY  FOR LIME
     One of  the  primary objectives to consider is the necessity of using lime.
Some data  indicate that the use of lime is not imperative;  the process could
be simplified  if the lime were eliminated.  Problems have been experienced
with coal-lime separations, loss of carbon values to the lime, and capture of
lime by the  coal.   These problems were not unexpected in the original plan for
the process, but the effect is more pronounced than desirable.

     Elimination of the lime would reduce the complexity of the process.  The
reactors could be made smaller, and gas usage would decrease because less
material would be handled.  Larger off-gas treatment facilities would be
necessary  to handle the increased sulfur in the off-gas.  Studies must be made
to determine which operating approach is economically and operationally superior.

OTHER COALS

     Tests using other,  typical sulfur-bearing coals should be made in the
thermobalance  and  batch reactors.   The results will be compared with results
already obtained.   The relative value of heating rates and holding times will
be evaluated.

PILOT UNIT

     Tests should  be made on the 10-inch unit used previously.  The larger
scale operation  and increased material generated are necessary for determining
details to complete the process flow sheet.   In particular, the determination
and distribution of sulfur types in the off-gas during continuous operation is
needed, so that  treatment facilities can be designed.

     If a heating  rate must be imposed on the particle (other than the rapid
heat-up in the fluidized-bed arrangement), the 10-inch unit will require
modification.  Further work is needed in the thermobalance  and batch reactors
to determine the optimum heat-up rate.

OVERALL CONCEPT  DESIGN

     When test work is completed,  data would be used to generate an overall
conceptual design  for the process.   This would include energy and material
balances,  economic  studies,  and all of the treatment steps  to produce a  low
sulfur fuel from coal.
                                      139

-------
                              REFERENCES CITED
1.   Clark, S. P., Jr., Ed., Handbook of Physical Constants.  New York:
     Geological Society of America, 1966.

2.   Kubaschewski, 0.  and Evans, E., Metallurgical Thermochemistry.
     London:  Butterworth-Springer, 1951.

3.   Rosenquist, T., "A Thermodynamic Study of the Iron, Cobalt, and
     Nickel Sulphides,"  J. Iron Steel Inst. (London) 176, 37-57 (1954)
     January.

4.   Rossini,  F. D. et al., Selected Values of Chemical Thermodynamic
     Properties.  Washington, B.C.:  U.S. Government Printing Office,
     1952.

5.   Snow, R.  D., "Conversion of Coal Sulfur to Volatile Sulfur Compounds
     During Carbonization in Streams of Gas,"  Ind. Eng. Chem. 24, 903-9
     (1932) August.

6.   Vestal, M. L. and Johnston, W. H., "Desulfurization Kinetics of Ten
     Bituminous Coals,"  Report No. SRIC 69-10.  Baltimore:  Scientific
     Research  Instruments Corp., 1969-
                                    140

-------
                                TECHNICAL REPORT DATA
                          (Please read law-act ions on the reverse before completing)
 JPA^600/^-77-206
,.TITLE AND SUBTITLE
Pilot Plant Study of Conversion of Coal to Low Sulfur
   Fuel
                                                       6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)              ~         —	—

Donald K. Fleming and Robert D. Smith
^PERFORMING ORGANIZATION NAME AND ADDRESS
Institute of Gas Technology
3424 South State Street
Chicago, Illinois  60616
12. SPONSORING AGENCY NAME AND ADDRESS     "
EPA, Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
                                                       3. RECIPIENT'S ACCESSION NO.
                                                       5. REPORT DATE
                                                        October 1977
                                                       8. PERFORMING ORGANIZATION REPORT NO



                                                       To. PROGRAM ELEMENT NO.

                                                       1AB013; ROAP 21AFJ-040
                                                       11. CONTRACT/GRANT NO.

                                                       68-02-1366
                                                       13. TYPE OF REPORT AND PERIOD COVERED
                                                       Final: 6/73-3/75
                                                       14. SPONSORING AGENCY CODE
                                                        EPA/600/13
15. SUPPLEMENTARY NOTES jERL-RTP project officer Lloyd Lorenzi Jr. is no longer with
EPA. For details contact Lewis D. Tamny, Mail Drop 61, 919/541-2709.
16. ABSTRACT
         The report gives results of a program to develop, on bench and pilot scales,
operating conditions for the key step in the IGT process to desulfurize coal by thermal
and chemical treatment.  This process, to date, uses the 'sulfur-getter' concept.  (A
sulfur-getter is a material that has a greater chemical affinity for sulfur than coal
has.) Lime was the sulfur-getter for this program. In Phase I,  a coal/lime mixture
was experimentally treated at atmospheric pressure with a reducing gas in a heated,
fluidized bed reactor, which could treat up to 200 Ib/hr of mixture to 1200 F.  The
coal was Illinois No. 6, containing about 3% sulfur. Initial work resulted in the dis-
covery that less sulfur was removed than expected. Two factors were believed res-
ponsible: the coal heat-up rate in the fluidized bed was nearly instantaneous, which
appeared to cause organic sulfur fixation; and the coal showed signs of weathering
(therefore, the total sulfur content was not readily available for hydrogen treatment).
Phase n redirected the program to the operation of smaller scale units featuring:
controlled  heat-up rates, an increased number of tests over a broader range of
conditions  (with savings in time  and  manpower), and coal samples from several U.S.
mines A coal/lime mixture was treated with hydrogen, in batch reactors, to 1500 F.
Tests indicated that lime treatment does not  capture all sulfur released from the coal.
                             KEY WORDS AND DOCUMENT ANALYSIS
                DESCRIPTORS
Air Pollution
Coal
Conversion
Desulfurization
-alcium Oxides
Fluidizing
3. DISTRIBUTION STATEMENT
Unlimited
                                          b.lDCNTIFIERS/OPEN ENDED TERMS
                                          Air Pollution Control
                                          Stationary Sources
                                          IGT Process
                                          Thermal Treatment
                                          Chemical Treatment
                                                   CLASS (TliisReport)
                                          Unclassified
                                          20 srxfuHITY CLASS (This page)
                                          Unclassified
                                                                   c.  COSATI (-kid/Group
13B
08G,21D
14B
07A,07D
07B
13H
21. NO. OP PAGFS
 153
                                                                   22. PFilCE
 Form 2220-1 {9-73J
                                      141

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                             MINISTERIO DE  MINAS Y  PETROI-EOS




              ilNISTlTUTO  NACIONAL. DE INVESTIGACIONES GEOL-OGICO-MINERAS



                                       INGEOMINAS
                         CERTIFICADO  DE PAZ  Y SAUVO
L-os  Suscri-f-os  funcionarlos  del  InstH-uto  Naclonal  de Inves-Hgaciones  Geologlco-Mineras







CERTIFICAN  :   que






quien  se ausen+a  del  Ins-M + u fo   por






                       19
con feoha
                                            no deja asuntos pendienl-es  por  concepto  de
Rondos  reclbldos,  legal izacion  de  cuen + as  y elementos  a  cargo, en sus  res-
pec*t-ivas  dependencies.
DEPENDENCIA

-------