e-ei' itwe*
x>EPA
United States
Environmental Protection
Agency
Industrial Environmental Research EPA-600/7-79-223
Laboratory September 1979
Research Triangle Park NC 27711
Heat Generation of
Spent Bed Materials
from Atmospheric
Fluidized-bed
Combustion of Coal
Interagency
Energy/Environment
R&D Program Report
-------
RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
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vironmental technology. Elimination of traditional grouping was consciously
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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 INTERAGENCY ENERGY-ENVIRONMENT
RESEARCH AND DEVELOPMENT series. Reports in this series result from the
effort funded under the 17-agency Federal Energy/Environment Research and
Development Program. These studies relate to EPA's mission to protect the public
health and welfare from adverse effects of pollutants associated with energy sys-
tems. The goal of the Program is to assure the rapid development of domestic
energy supplies in an environmentally-compatible manner by providing the nec-
essary environmental data and control technology. Investigations include analy-
ses of the transport of energy-related pollutants and their health and ecological
effects; assessments of, and development of, control technologies for energy
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This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
-------
EPA-600/7-79-223
September 1979
Heat Generation of Spent Bed Materials from
Atmospheric Fluidized-bed
Combustion of Coal
by
Rhyne H. Kim
EPA, Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
Program Element No. INE825
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Washington, DC 20460
-------
Abstract
The hydration process of the spent bed material of the atmospheric
fluidized-bed combustor, with a calcium-to-sulfur ratio of 3, was investi-
gated for its maximum temperature, rate of temperature rise, and the con-
trollability of the temperature rise with various quantities of water. Tap
water was supplied through a rainfall simulating device. For the volume
ratio of the spent bed material to water larger than 1.2, the temperature
of the spent bed malarial rose to 77°C (170°F); at ratios less than 1.2, the
maximum temperature of the material was 132°C (270°F). Rates of tempera-
ture rise in the uncontrolled hydration process were higher than those of
the controlled hydration processes. The hydration process expanded the
volume of the spent bed material faster than that caused by moisture in the
atmosphere when the spent bed material was exposed to the ambient atmosphere,
n
-------
TABLE OF CONTENTS
ABSTRACT
LIST OF TABLES
LIST OF FIGURES
INTRODUCTION
PURPOSE
CONCLUSIONS
RECOMMENDATIONS
DESIGN OF APPARATUS
PROCEDURE
FBCR SAMPLES
RESULTS AND DISCUSSION
REFERENCES
APPENDICES:
I. FLOW RATE HISTORIES
II. RUN DATA AND TYPICAL RECORDER RESULTS
III. PRECIPITATION AND EVAPO
RANSPIRATION AT
MORGANTOWN, WEST VIRGINIA
IV. MEMORANDUM FROM R. H. KIM TO P. P. TURNER,
DTD APRIL 19, 1978
Page
11
iv
v
1
3
4
4
6
23
24
24
36
37
45
59
61
m
-------
LIST OF TABLES
Table Title Page
1 Fluidized Bed Combustor/SATR Conditions 26
2 T , t at Three Positions 27
3 The Maximum Temperature, Flow Rate, Time 29
for T , etc. for Each Run
II-l Temperature History for Run No. 1 46
11-2 Temperature History for Run No. 2 47
11-3 Temperature History for Run No. 3 48
11-4 Temperature History for Run No. 4 49
11-5 Temperature History for Run No. 5 50
11-6 Temperature History for Run No. 6 51
11-7 Temperature History for Run No. 7 52
11-8 Temperature History for Run No. 8 53
11-9 Temperature History for Run No. 9 54
11-10 Temperature History for Run No. 10 55
11-11 Temperature History for Run No. 11 56
IV
-------
LIST OF FIGURES
Figure Title Page
1 Top View and Cross Section AA of Water Holder 7
2 Short Square Column 9
3 Short Column and Its Operating System 10
4 Temperature History of Run No. 1 12
5 Temperature History of Run No. 2 13
6 Temperature History of Run No. 3 14
7 Temperature History of Run No. 4 15
8 Temperature History of Run No. 5 16
9 Temperature History of Run No. 6 17
10 Temperature History of Run No. 7 18
11 Temperature History of Run No. 8 19
12 Temperature History of Run No. 9 20
13 Temperature History of Run No. 10 21
14 Temperature History of Run No. 11 22
15 Dimensionless Temperature History at the 31
Initial Contact of Water with FBCR
16 Dimensionless Temperature History at 32
Thermocouple Position 2
17 Dimensionless Temperature History at 33
Thermocouple Position 3
1-1 Flow Rate History and Its Average for Run No. 1 38
1-2 Flow Rate History and Its Average for Run No. 2 38
1-3 Flow Rate History and Its Average for Run No. 3 39
1-4 Flow Rate History and Its Average for Run No. 4 39
1-5 Flow Rate History and Its Average for Run No. 5 40
1-6 Flow Rate History and Its Average for Run No. 6 41
1-7 Flow Rate History and Its Average for Run No. 7 42
1-8 Flow Rate History and Its Average for Run No. 8 43
1-9 Flow Rate History and Its Average for Run No. 9 43
1-10 Flow Rate History and Its Average for Run No. 10 44
II-l A Typical Result from a Recorder at the Initial 57
Contact of Water for FBCR (Thermocouple 1)
11-2 A Typical Result from a Recorder at 58
Thermocouple Positions 2 and 3
-------
Introduction
A fluidized-bed combustor is a furnace in which pulverized coal and
limestone are mixed with air and burned in a fluid-like consistency at
atmospheric conditions. Calcined limestone captures sulfur dioxide in the
furnace. Since the operating temperature of the furnace is only about
850°C (1562°F), atmospheric nitrogen is not fixed. The nitrogen oxides pro-
duced are from the nitrogen content of the coal only; thus the amount of
nitrogen oxides produced are less than in conventional combustion. Particu-
lates can be controlled by a properly designed baghouse. Recent studies
have shown that the atmospheric fluidized-bed combustor (AFBC) would meet
1 2
the current and recently modified new source performance standards. The
AFBC would then be competitive with a furnace having a flue gas desulfuri-
zation device.
Solid residues exhausted from the bed would be in significant quantity
3
since the AFBC would be used increasingly by industry and utilities.
Carry-over would increase considerably and hydration of quicklime may take
place whether in temporary storage or in a landfill for permanent disposal
4
of the solid bed material and carry-over. Hern et al. reported that the
solid bed residues have 27-38% of active Ca component. The hydration of
5
quicklime is violent and releases a significant amount of heat. An initial
contact of the fluidized-bed combustor residues (FBCR) with water through a
rainfall or runoff would create an unexpected change in the storage or in
the landfill unless the FBCR is exposed to air for a long time, since the
unused quicklime in the FBCR would undergo hydration, releasing heat and
changing the structure of the components in the residues.
-------
Stone and Sun have studied characteristics of the hydration process
of the unused quicklime, and have found that the reaction of quicklime is
a function of the solid residue to water ratio. They recognized the heat
generation of quicklime as a future problem in storage or in the landfill
operation when it is exposed to atmospheric moisture.
-------
Purpose
The purpose of this study was to determine: (1) if there is a way to
control a temperature rise due to the hydration process, and (2) if the
method of constant head or constant flux for the hydraulic diffusion coeffi-
o
cient is applicable to the transient unsaturated solid with moisture. In
previous studies, the FBCR was contacted with water at a certain ratio of
solid to water by weight or any arbitrary ratio in a container. The present
experimental study simulates rainfall so that water drops penetrate the FBCR
in a short column.
-------
Conclusions
Short columns and a water holder for simulating rainfall were designed to
measure rates of temperature rise as water dropped to the fluidized-bed com-
bustor residue (FBCR) through the water holder holes. Simulation of rain-
fall appeared to be 5.08-10.16 cm (2-4 in.), equivalent to precipitation
during the summer months. The flow rates were all very rapid, even when fine
filter paper was used* Smaller holes in the base plate of the water holder,
as originally planned, aright have been more successful In controlling-flow
rate.
The maximon -tEmperature of the FBCR, as it was hydrated, was about 132°C
C27Q°F) at a itepth of 10.16 on (4 in.) and deeper from the surface of the
FBCR. The quantity of water needed to control the FBCR below 77°C 07D*F)
in the hydration process was 1500 tart3 for 1800 cm3 of the FBCR,
The rates of temperature rise seemed to be of two types: a slow rate
for controlling the FBCR to 77°C (170°F), and a fast rate for uncontrolled
hydration processes. At either rate, the volume of the FBCR expanded.
Recommendations
*<
1. Improvement of the water holder. The holes in the base plate of
the water holder were 0.1588 cm (1/16-in.) in diameter. It is now
recommended that 0.0794 cm (1/32-in.) in diameter holes be used,
so flow rates can be better controlled using the level adjuster of
the water holder.
-------
2. A wide range of flow rates is recommended, using a number of base
plates with different size holes. The base plate should be bolted
against a gasket on the side plates.
3. The column for controlling temperature rise should be scaled up
by keeping the volume ratio of rainfall to the FBCR constant
(approximately 8/9).
4. Longer time duration (more than 3 hours) for a volume expansion
should be tried for complete expansion.
5. The thermal diffusivity of the FBCR having various moisture contents
is recommended for a measurement. By doing so, a numerical solution
for a temperature distribution (while the hydraulic diffusion takes
place) is possible.
6. Chemical composition of the FBCR before and after hydration is
recommended for a further study, using X-ray defraction or a
scanning electronmicroscope.
-------
Design of Apparatus
Recently, the activity of FBCR has been studied experimentally. Water
was poured in a glass or plastic container containing FBCR * . In usual
landfills or storage of FBCR, initial contact between the FBCR and water is
through infiltration of rainfall. Atmospheric moisture affects the FBCR very
slowly; the hydration process may generate hardly any heat; however, it may
change the chemical structure of the unused calcined lime and calcium
sulfate, thus increasing volume of the FBCR. Simulation of rainfall on the
FBCR in a container is more "natural* than pouring water on the FBCR in the
container. The rainfall simulation apparatus consisted of a water holder,
a short square column, and other apparatus.
1. Water holder (see Figure 1). Once rain starts penetrating through
the FBCR, the water flow is one dimensional in an almost vertical plane. The
penetration of water is observed through a 15.24 x 15.24 cm (6 x 6 in.) base
and 30.48 cm (12 in.) high column. An even distribution of water flow is
sought from the water holder. The water holder base is a square piece of
Plexiglas: 20.3 cm (8 in.) on a side and 1.27 cm (1/2-in.) thick. Thirty-
six holes (0.16 cm OD, 1/16-in.) are drilled so that each hole covers a
2.54 cm2 (1 in.2) area when water passes through the holes through the base
of the water holder. On one side near the base, is a 0.64 cm (1/4-in.) OD
Plexiglas tube. The height adjustment of the tube above the base determines
the constant head of water in the holder, giving a steady flow rate. The
side plates are glued to the base with epoxy resin.
-------
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' TOP VIEW
r
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v\\\\i N\\ ik\\M! \V
\\V;\\\\\l;k\\\V
A
WATER LEVEL ADJUSTER
/
UNIT EQUIVALENTS
in. cm
1/8 0.318
3/8 0.953
1 2.54
11/2 3.81
5 12.70
it || 1
SECTION AA 'A" units are 'ncnes)
Figure 1. Water holder (not to scale).
-------
2. Short square column (see Figure 2). The original short square
column was Plexiglas with inside dimensions of 15.24 x 15.24 x 30.48 cm
(6 x 6 x 12 in.). Each pair of edges is glued together with epoxy which
would retain its strength up to 310°C (500°F). The edges are fastened addi-
tionally by bolts at 5.08 cm (2 in.) intervals. An opening in the base has
a Swage!ok fitting for a connecting tube.
On one side of the plates, starting 5.08 cm (2 in.) from the base plate,
are six Swagelok adapters for the thermocouples and a U-tube manometer.
Properly adjusting the Swagelok nuts prevents the column from losing water.
Results from several initial experiments indicated that the highest tempera-
ture rise is above the molding temperature range of Plexiglas. The midsec-
tion square cross-section column was slightly deformed after a few hydration
experiments. A stainless steel column was prepared to avoid this deformation.
The cylindrical stainless steel container (shown in the inset of Figure 3)
is 16.5 cm (6-1/2 in.) in diameter and 15.87 cm (7-5/8 in.) high; it had four
thermocouple adapters, one above the other. The adapters are 5.08 cm (2 in.)
apart; the bottom one is 2.54 cm (1 in.) above the base.
In order to simulate rainfall on the FBCR placed in a column, the water
holder was put aside until steady flow was established using a peristaltic
pump and slowly moving the turning arm which supports the water holder with a
holder base. See Figure 3.
8
-------
1/8 PIPE THREAD
(a) TOP
12
UNIT EQUIVALENTS
in.
V2
2
6
12
cm
1.27
5.08
15.24
30.48
(All units are in inches)
(b) FRONT
Figure 2. Short square column (not to scale).
-------
S.S. COLUMN
RECORDER
RECORDER
TURNING ARM
HOLDER ROD
WATER HOLDER
HOLDER BASE
WATER LEVEL ADJUSTER
SINK
Figure 3. Short column and its operating system.
10
-------
The initial experiments indicated that 36 holes of the water holder provide
excessive flow rates when they are compared with an average rainfall of the
g
West Virginia area. . Several filter paper types were used to cover the
holes. It turned out that the longer term use of filter paper yielded greater
flow rates; flow rates with filter paper were proportional to time. A few
plots of flow rates vs. time were made. Within the limit of applications,
flow rates changed linearly with time. See Figures 4-14. Flow rates were
also controlled by covering 20 outer holes. The quantity of water for each
experiment was determined by the average flow rate from the flow rate vs time
diagram. Accuracies of the flow rates are estimated to be +5 percent.
3. Other apparatus. Other apparatus used in the experiments include:
a. Angus Temperature Recorder with K-type thermocouples.
b. Cole-Palmer Two-Pen Recorder with 1 mv attenuator capability.
c. K-type thermocouples with OMEGA-CJ reference junction
compensators. Time constant of the thermocouple is on
the order of 1 second. Accuracy of the thermocouple
is in the range of -17 to -15°C (2-5°F).
d. Electronic scale (to four decimal places).
11
-------
*
I
O THERMOCOUPLE NO. 1
Q THERMOCOUPLE NO. 2
THERMOCOUPLE NO. 3
0.8 —
0.7
10
90
100
Figure 4. Temperature history of run No. 1.
-------
CO
O THERMOCOUPLE NO. 1
D THERMOCOUPLE NO. 2
A THERMOCOUPLE NO. 3
0.8
0.7
10
90
100
Figure 5. Temperature history of run No. 2.
-------
O THERMOCOUPLE NO. 1
Q THERMOCOUPLE NO. 2
THERMOCOUPLE NO. 3
40 50
TIME, minutes
90 100
Figure 6. Temperature history of run No. 3.
-------
1.00
0.95
E
en
0.90
0.85
Q THERMOCOUPLE NO. 2
A THERMOCOUPLE NO. 3
NOTE: THERMOCOUPLE NO. 1 SHOWED
NO CHANGE FROM AMBIENT.
I
20
40
60
80
100 120
TIME, minutes
140
160
180
200
220
Figure 7. Temperature history of run No. 4.
-------
THERMOCOUPLE NO. 1
THERMOCOUPLE NO. 2
A THERMOCOUPLE NO. 3
90
100
Figure 8. Temperature history of run No. 5.
-------
1.0
0.9
0.8 -
0.7
10
20 30
40
50
TIME, minutes
60
O THERMOCOUPLE NO. 1
n THERMOCOUPLE NO. 2
A THERMOCOUPLE NO. 3
70
80
90 100
Figure 9. Temperature history of run No. 6.
-------
1.0
0.9
00
0.8
0.7
O THERMOCOUPLE NO. 1
Q THERMOCOUPLE NO. 2
A THERMOCOUPLE NO. 3
J.
_L
10
20
30
40
50 60
TIME, minutes
70
80
90
100
110
Figure 10. Temperature history of run No. 7.
-------
1.0
0.9
0.8
0.7
O
O THERMOCOUPLE NO. 1
Q THERMOCOUPLE NO. 2
THERMOCOUPLE NO. 3
10
20
30
40
50
TIME, minutes
60
70
80
90
100
Figure 11. Temperature history of run No. 8.
-------
1.0
0.9
to
o
0.8
0.7
D THERMOCOUPLE NO. 2
A THERMOCOUPLE NO. 3
NOTE: THERMOCOUPLE NO. 1 SHOWED
NO CHANGE FROM AMBIENT.
10
20
30
40
50
TIME, minutes
60
70
80
90
100
Figure 12. Temperature history of run No. 9.
-------
1.0
0.9
to
0.8
0.7
O THERMOCOUPLE NO. 1
O THERMOCOUPLE NO. 2
A THERMOCOUPLE NO. 3
I
I
I
10 20 30 40 50 60 70 80
TIME, minutes
90
100
110
120
130
140
Figure 13. Temperature history of run No. 10.
-------
to
1.0
0.9
0.8
0.7
10
20
O THERMOCOUPLE NO. 1
D THERMOCOUPLE NO. 2
A THERMOCOUPLE NO. 3
THERMOCOUPLE NO. 4
30
40
50
TIME minutes
60
70
80
90
100
Figure 14. Temperature history of run No. 11 (in Plexiglas column).
-------
Procedure
1. Place thermocouples at locations provided with adapters.
Note: Thermocouple No. 1 is at the surface. Below
it are thermocouples No. 2 and 3, respectively.
Thermocouple No. 3 is 10.2 cm (4 in.) or 2.54 cm
(1 in.) from the base of the square (Plexiglas)
or cylindrical (steel) column, respectively.
2. Measure the volume of the fluidized-bed combustor residue (FBCR)
with a beaker.
3. Fill the column with the FBCR and measure the height of the FBCR.
4. Keeping the water holder away from the column, turn on the water,
switch on the peristaltic pump, and wait until water reaches the predetermined
level adjusted by the drain tube of the water holder.
5. Measure the flow rate of the water holder (using a stopwatch and a
graduated cylinder) and record the time at which reading was made.
6. Start the recorder at 1 cm/min. and swing the water holder to a
position above the column, keeping water drops away from the edges of the
column to avoid channeling.
7. Push the water holder set away from the column to stop the water
supply after a predetermined duration.
Note: Temperature histories at thermocouples No. 1, 2,
and 3 are recorded automatically.
23
-------
8. When the temperature at thermocouple No. 3 reaches 77°C (170°F),
stop the recorders, measure the height change of the FBCR, and clean up the
hydrated FBCR from the column.
9. Water can be re-supplied after the temperature gets to the plateau
at the maximum to observe the rate of cooling as water is supplied.
10. Turn off water.
FBCR Samples
Three samples were tested. The first sample was obtained under non-steady
state conditions of the Sampling and Analytical Test Rig: repeatability of
the hydration processes was impossible to establish. The other two samples
were obtained under steady state operation. Table 1 illustrates the combustor
conditions for the various runs. Note that calcium/sulfur (Ca/S) ratios for
the samples are 3 and 3.3 for the second and third samples, respectively.
Results and Discussion
Tables II-l through 11-11 are temperature histories of all experiments in
tabular form. A typical run is also shown in Appendix II. The maximum tem-
perature, T , and the time, tm, at which Tm occurred at each thermocouple are
listed in Table 2. Maximum temperatures are in the range of 22°-130°C
(72°-266°F). It is seen from Table 2 that maximum temperature took place at
24
-------
thermocouples 2 and 3 at almost the same time and somewhat later at thermo-
couple 1. The maximum temperature at thermocouple 1 is generally lower than
those at thermocouples 2 and 3, since the initial contact of water with the
FBCR is made at thermocouple 1; heat generated is taken away with water flow
faster than heat at thermocouples 2 and 3. Table 3 lists, for each run, the
volume of the FBCR, total volume of water, the volume ratio of FBCR to water,
the maximum temperature, the time at which the maximum temperature occurs,
water holding capacity, t duration, the percent volume change, and resupply
of water or not. The reason for the resupply of water is to observe how fast
cooling takes place in the FBCR after the temperatures at thermocouples 2 and 3
level off at T .
m
25
-------
Table 1
FLUIDIZED BED COMBUSTOR/SATR CONDITIONS
Coal type
Sorbent type
Air velocity, m/sec (ft/sec)
Bed temperature, °C (°F)
Excess Air, %
Ca/S ratio
Bed height, m (in.)
Bed area, m2 (in.2)
Total air flow
m3/min (scfm)
Coal feed rate,
kg/hr (Ib/hr)
Sorbent feed rate
kg/hr (Ib/hr)
Sample I
Arkwright 1/4 x 50
Greer limestone 8 x 20
1.37 (4.5)
868 (1595)
22
3
0.76 (30)
0.21 (325)
4.56 (161)
21.79 (48)
6.81 (15)
Sample II
Arkwright 1/4 x 50
Greer 1imestone 8 x 20
1.37 (4.5)
871 (1600)
22
3.3
0.76 (30)
0.21 (325)
4.56 (161)
28.6 (63)
9.08 (20)
26
-------
Table 2
Tm AND tm AT THREE POSITIONS
Run No.
la
2a
3a
4ab
5a
6
7
8
9b
loa
lia
Thermocouple Locations
1
T °r (°f\
'm» ^ v r;
100 (212)
100 (212)
62 (143)
96 (205)
99 (210)
48 (118)
22 (72)
99 (210)
22 (72)
tm, min.
27
33
54
45
21
95
0
46
0
2
T °C (°E\
'rn> "" \ N
123 (254)
119 (247)
118 (245)
66 (151)
119 (246)
105 (221)
74 (166)
46 (114)
129 (264)
130 (266)
43 (109)
tm, min.
27
28
53
207
40
18
87
11
15
45
21
3
T °(] (°p)
124 (256)
122 (252)
111 (231)
57 (135)
124 (255)
117 (243)
76 (168)
98 (208)
125 (257)
129 (264)
58 (137)
tm, rnin
27
33
53
207
40
18
75
9
17
46
30
Notes: a) Using Sample I of Table 1; Sample II was used in the other four runs.
b) No change from ambient.
27
-------
Figures 4-14 show temperature histories with normalization of the tempera-
tures with respect to the maximum temperature for each run. All runs except the
one covered by Figure 14 were made in the stainless steel column; the run of
Figure 14 was made in the Plexiglas column. Observations from these Figures
4-14 and Tables 1-3 follow:
1. Controllability of temperature increase of the FBCR. A purpose of
this experiment was to determine a technique to control temperature increase
due to the lime hydration process as it contacts water. The control tech-
nique is to keep the temperature of the FBCR below 77°C (170°F), above
which the lysimeter material, Plexiglas, will be deformed. Run No. 4
supplied 18,972 ml of water for a 63-minute period; this resulted in a maximum
temperature of 66°C (151°F), occurring 207.3 minutes after the experiment was
started. The experiments by Sun confirm these results: the
volume ratio of the FBCR to water is less than or equal to 1. Note that,
regardless of mixing the FBCR and water, the temperature rise can probably
be controlled if the ratio of the FBCR to water by volume is near or less
than 1.
As the FBCR/water ratio increases beyond 1.2, heat generation in the hydra-
tion processes becomes spontaneous, with maximum temperatures reaching
about 127°C (260°F), which is higher than the saturation temperature of 1
atmosphere. See Table 3. The maximum temperature at the surface of the
FBCR is in the range of 48°-100°C (118°-212°F), except for runs No. 8 and
No. 11 which did not get above ambient.
28
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Table 3
THE MAXIMUM TEMPERATURE, FLOW RATE, TIME FOR t
m»
ETC. FOR EACH RUN
Run No.
1
2
3
4
5
6
7
8
9
10
11
FBCR
(ml)
2250
1800
1800
1800
2250
1800
1800
1800
1350
1800
1750
Water
(ml)
559.8
197.1
182
18972
2754.2
254
1500
2608.5
107.1
219.2
3650.4
FBCR/Water T
(ml /ml) (T)
4.02
9.12
9.89
0.95
0.818
7.086
1.2
0.69
12.6
8.21
0.479
256
252
245
151
255
243
168
208
264
266
137
(min)
27
33
52.8
207.3
40
18
75
9
15
45
30
WHCa
2.285
2.285
2.285
2.285
2.285
2.3784
2.3784
2.3784
2.3784
2.285
2.285
t duration Volume
(min) change (%)
6
3
14
63
47
8
24
47
3
4
78
--
61.2%
48.2
No change
—
38.3
21.8
—
33.9
No change
Resupply of
water
Provided
11
Not provided
It
aWater holding capacity = weight of FBCR/weight of water.
Density of sample I = 1.160 gm/cm ; Density of sample II = 1.287 gm/cm .
-------
The FBCR at thermocouples 2 and 3 would maintain a temperature above
77°C (170°C) at least for more than an hour as it undergoes the hydration
process, implying that the Plexiglas column would be deformed seriously
toward the base of the column. Results of resupplying water after the tem-
perature reaches the maximum temperature plateau are to accelerate cooling
of the FBCR so that 1 hour period above 77°C (170°F) can be shortened to
20-30 minutes. (See Figures 4, 5, 9, and 11.) However, resupplying water
after temperature reaches the maximum plateau is not a satisfactory control
method for temperature increases.
Q
Taking the monthly average rainfall of the West Virginia area, the amount
of water for controlling the temperature below 77°C (170°F) corresponds to
a 4-month net flux for 1800 ml FBCR.* Therefore, changes in pH of runoff
or leachates would be significant in the entire hydration process; pH in
the initial stage of hydration would change drastically.
2. Heat generation. Figure 15 presents a normalized temperature history
at thermocouple No. 1 based on all of the runs. Using the maximum temperature,
T , from each run and the time, tm, at which Tm occurred, temperatures and
times are normalized and their dimensionless temperature histories are
plotted. In a similar manner, Figures 16 and 17 are normalized to yield
dimensionless temperature histories at thermocouples 2 and 3, respectively.
Figures 15 and 16 indicate two distinctive types of temperature histories:
one for experiments in which complete temperature control to 77°C (170°F)
was possible; the other in which hydration takes place with an insufficient
amount of water for temperature control. However, thermocouple No. 3
*See Appendix III
OU
-------
1.0
0.9
o
*
o
0.8 ~
0.7
1 1 1 1
r..
D •
[
* ^D °8V^DA^
L ^
K ^^ ^
1 1 1 1 1
0 0.1 0.2 0.3 0.4
I I I I I
O RUN NO. 1 • RUN NO. 7
D RUN NO. 2 • RUN NO. 8
A RUN NO. 3 A RUN NO. 9
0 RUN NO. 4 + RUN NO. 10
O RUN NO. 5 • RUN NO. 11 r
V RUN NO. 6 C
. . .-,
D
. •
•° • '°1
O
^ A
11 O V A A
V A
V
<
1 1 1 1 1
0.5 0.6 0.7 0.8 0.9 1.
t/tm (min./min.)
Figure 15. Dimensionless temperature history at the initial contact of water with FBCR.
-------
1.0
• 1 1
1
o
D
e
o
V
— i—
RUN
RUN
RUN
RUN
RUN
RUN
NO.
NO.
NO.
NO.
NO.
NO.
1
2
3
4
5
6
~l
• RUN
• RUN
A RUN
* RUN
• RUN
1
NO.
NO.
NO.
NO.
NO.
7
8
9
10
11
i ' n D ' A-N^
0«A 1
^
• • * A^^^^
• • A
0™
« m
O A * • ^
0.9
O
£
o
[S3
0.8
0.7
0.1
D
D
0
D
O
0
i
0 4
0
A
A
o
A
O
O
o o
O
i
O
A
A
0.2 0.3 0.4 0.5
t/tm (min./min.)
0.6
0.7
0.8
O
0.9
•-
o
.
1.0
Figure 16. Dimensionless temperature history at thermocouple position 2.
-------
1-°| 1 1 1— I I I I I u ul •„ • 0^ o
I * • ^ D .
D
00 £ 0 A A
CO -t V ^
H
•
1 • • D * A
0.8 F- O
^ A A
t\ "7
o o n u
7 ° D fc ° o
A A
D AQ A A OA °
A A
I I l I l I I I I
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.
t/tm (min./min.)
Figure 17. Dimensionless temperature history at thermocouple position 3.
-------
gives no indication of the two types of histories. (See Figure 17.) The first
type appears to be curve with a slower slope than the second, indicating that
generated heat is quickly dissipated through the infiltrating water. However,
in a deeper location, the rate of heat generation exceeds its dissipation rate,
yielding a higher temperature.
Thermal gradients in the FBCR may cause water to move from warm to cool
areas in both the liquid and vapor phases, and the rate of transfer may be
greater than can be predicted with Pick's law and the diffusion coefficient
for water vapor into air. Several investigations have been published on
1113
two-phase heat and mass transfer from stationary sources. However, no
work has been reported on two-phase heat and mass transfer from a mobile
heat source.
In this description of flow behavior, hydraulic diffusion is coupled
with thermal diffusion. The device used does not seem to furnish proper
data for transient hydraulic diffusion. Until the FBCR is fully saturated,
the permeability coefficient of the FBCR cannot be obtained. Once the FBCR
is fully saturated with water at a given temperature, the permeability
o
coefficient can be observed. This is a condition in which heat is not
generated: heat is transferred at a steady state so that thermal gradients
are fixed through the layer of the FBCR.
34
-------
3. Changes in chemical characteristics. As the hydration process takes
place, quicklime and calcium sulfate absorb water and become components which
are chemically different from the original components. Test duration for heat
14
generation was in the range of 2.5 to 3 hours. Mehta reports that the
hydration can be extended to 6 hours and that volume expansion occurs as in
commercial cement. This suggests that the 2.5 to 3 hour test may not be
long enough to observe the FBCR volume expansion.
The main concern of the experimental investigation was to find a tempera-
ture control technique. However, the FBCR volume expansion may crack the
FBCR and eventually lead to channeling FBCR landfills. The channeling may
cause leachate infiltration, accelerating ground water contamination.
Further investigation of the volume expansion phenomenon is desirable.
35
-------
References
1. Newby, R. A., et al., "Assessment of the Impact of S02, NOX and Particulate
Emission Standards on Fluidized-Bed Combustion System Design and Energy
Cost," M78-68, Proc. of the Fifth International Conference on Fluidized
Bed Combustion, Vol. II, pp. 875-90, The Mitre Corp., December 1978.
2. Reese, J.T., "Utility Boiler Design/Cost Comparison: Fluidized-bed Com-
bustion Versus Flue Gas Desulfurization," EPA-600/7-77-126 (NTIS
No. PB 280 751), November 1977.
3. Badin, E. J., "Utilization of By Products Ash from Fluidized Bed Combustion
of Coal," MTR-7339, Rev. 1, Metrek/Mitre, September 1976.
4. Hern, I. R., et al., "Characterization of Fluidized Bed Combustion Waste,
Composition and Variability as They Relate to Disposal on Agri-
cultural Lands," M78-68, Proc. of the Fifth International Conference
on Fluidized Bed Combustion, Vol. II, pp. 833-39, The Mitre Corp.,
December 1978.
5. Boynton, B. S., Chemistry and Technology and Lime and Limestone. Inter-
science, New York, 1966.
6. Stone, R., and R. L. Kahle, "Environmental Assessment of Solid Residues
from Fluidized-Bed Fuel Processing: Final Report," EPA-600/7-78-107
(NTIS No. PB 282 940), June 1978.
7. Sun, C. C., C. H. Peterson, and D. L. Keairns, "Environmental Impact of
the Disposal of Processed and Unprocessed FBC Bed Material and
Carry-Over," M78-68, Proc. of the Fifth International Conference
on Fluidized Bed Combustion, Vol. II, pp. 846-73, The Mitre Corp.,
December 1978.
8. Standard Method of Test for Permeability of Granular Soils (Constant
Head) ASTM D2434, 1977 Annual Book of ASTM Standards.
9. Friel, E. A., et al., "Water Resources of the Monongahela River Basin,
West Virginia," U.S. Geological Survey, 1967.
10. Gary, J.W., "Water Flux in Moist Soil: Thermal Versus Suction Gradients,"
J. of Soil Science, Vol. 100, No. 3, pp. 168-175, 1965.
11. Slegal, D. L., and L. R. Davis, "Transient Heat and Mass Transfer in
Soils in the Vicinity of Heated Porous Pipes," J. of Heat Transfer,
Vol. 9, pp. 541-46, November 1977.
12. Danckwertz, P. V., "Absorption by Simultaneous Diffusion and Chemical
Reactions," Trans, of the Faraday Soc.. Vol. 26, pp. 300-304, 1956.
13. Carslow and Jaeger, Conduction of Heat in Solids, Oxford Press, p. 395,
1947.
14. Mehta, P. K., "Effect of Lime on Hydration of Pastes Containing Gypsum
and Calcium Aluminates or Calcium Sulfoaluminate," J. of the
American Ceramic Soc.. Vol. 55, No. 6, pp. 315-319, 1973.
36
-------
APPENDIX I
FLOW RATE HISTORIES
Flow rate histories and average flow rates for each run are shown in
Figures 1-1 through 1-10, following.
For periods of testing, average flow rates are linear in most runs
as shown by the arrows intersecting the "y" axes. Their averages are used
to compute the total quantity of flow supplied to the FBCR.
37
-------
c
'E
<
£T
110
100 -
12:00 12:30 13:00 13:30 14:00
TIME, Hrrmin.
Figure 1-1 Flow rate history and its average for run No. 1.
<
CC
100
90
80
70
66 ml/mm.
10:00
11:00
TIME, Hrmin.
12:00
Figure 1-2. Flow rate history and its average for run No. 2.
38
-------
<
cc
30
c
£
I 2°
§
10
13 ml/min.
0
10:00
11:00
12:00
TIME, Hrmin.
Figure 1-3. Flow rate history and its average for run No. 3.
15:00 15:30 16:00
TIME, Hrmin.
Figure 1-4. Flow rate history and
its average for run No. 5.
13:00
39
-------
100
1
LU"
I-
<
cc
O
WATER SUPPLY DURATION
10:00
11:00
12:00 12:30
TIME, Hr:min.
Figure I-5. Flow rate history and its average for run No. 6.
40
-------
100
WATER SUPPLY DURATION
10 -
8:00
TIME. Hrmin.
Figure I-6. Flow rate history and its average for run No. 7.
11:00
41
-------
100
c
E
EC
o
WATER SUPPLY
DURATION
10 —
2:00
3:00
— 47min. >
TIME, Hr.min.
4:00
Figure 1-7. Flow rate history and its average for run No. 8.
42
-------
. 40
c
£
<
cc
30
20
I r
35.7 ml/min.
I
.WATER SUPPLY DURATION
8:00 8:30 9:00
TIME, Hr:min.
9:30
Figure 1-8. Flow rate history and its average
for run No. 9.
WATER SUPPLY DURATION
9:00 9:30 10:00
TIME, Hr:min.
Figure I-9. Flow rate history and
its average for run No. 10.
43
-------
90
WATER SUPPLY
DURATION
2:00 2:30 3:00 3:30 4:00
TIME, Hr:min.
Figure 1-10. Flow rate history and jts average for run
No. 11.
44
-------
APPENDIX II
RUN DATA AND TYPICAL RECORDER RESULTS
Tables II-l through 11-11, following, are temperature histories for
all runs.
Figure II-l, following, represents a recording from an Angus Recorder,
at a chart speed of 0.5 in./min (1.27 cm/min.). The temperature scale
appears on the graph. The temperature history is for thermocouple No. 1
(at the surface).
Figure II-2, following, shows temperature histories for thermocouples
No. 2 (heavier line) and 3 in the FBCR. The reference for the trace for
thermocouple No. 2 is the base of the graph. That for No. 3 is 1 in.
(2.54 cm) above the base. At a chart speed of 1 cm/min, 1 in. (2.54 cm)
represents 1 mv.
45
-------
TABLE II-l. TEMPERATURE HISTORY FOR RUN NO. 1
Time
(min.)
0
2
2.2
4
5
10
15
20
25
26
26.3
27
28
29
30
31
32
33
34
40
42
52
55
60
65
70
No. 1
74
74
75 '
85
95
113
120
212
212
210
205
190
175
100
88
77
Thermocouple
No. 2
75
75
77
80
82
94
113
139
200
223
249
252
254
252
252
252
252
249
244
219
146
139
127
125
119
114
No. 3
77
77
95
104
104
101
125
156
223
245
254
256
255
254
253
253
253
252
247
237
201
193
182
176
166
157
46
-------
TABLE 11-2. TEMPERATURE HISTORY FOR RUN NO. 2
Time
(min.)
0
3
6.4
7
7.7
10
11
12
15
20
23
25
28
28.4
29
29.3
30.5
33
34.3
37
38
39
40
41
42
43
44
45
46
50
No. 1
72
67
83
100
155
212
211
210
70
63
63
63
63
Thermocouple
No. 2
73
73
73
87
91
91
85
87
97
116
149
221
247
247
247
238
232
. 204
148
121
108
102
99
91
82
58
No. 3
77
77
89
91
88
95
98
102
114
139
146
245
250
251
252
248
243
234
222
199
195
186
178
157
135
73
47
-------
Table 11-3. TEMPERATURE HISTORY FOR RUN NO. 3
Time
(min.)
0
4
5
6
13
16
17
18
25
30
35
40
41
45
46
46.4
46.8
47
48
50
51
52
52.8
53
54
55
56
57
58
59
60
61
66
71
75
80
83
90
95
100
No. 1
71
71
71
71
71
71
75
77
115
135
140
143
142
136
133
125
120
118
83
71
71
71
71
Thermocouple
No. 2
73
73
72
71
68
69
70
71
99
112
124
140
160
169
173
208
209
211
225
239
244
245
245
242
240
236
232
230
225
222
217
205
192
183
174
166
140
138
131
No. 3
73
73
73
72
72
72
73
74
85
89
98
99
108
110
113
125
126
129
152
211
227
231
231
229
227
225
214
211
205
202
197
179
161
148
137
130
115
107
104
48
-------
Table I1-4. TEMPERATURE HISTORY FOR RUN NO. 4
Time Thermocouple
(min.) No. 1 No. 2 No. 3
0 64 64 66
70 64 63
85 68 73
100 77 80
115 85 88
130 95 95
145 106 104
160 111 112
175 126 117
190 137 124
205 150 132
207.3 151 135
210, 151 133
49
-------
Table 11-5. TEMPERATURE HISTORY FOR RUN NO. 5
Time
(min.)
0
5
13
20
22
24
32
36
37
39
39.5
40
42
44
45
47
48
50
51
55
57
57.6
60
65
67
70
72
85
90
95
100
No. 1
74
74
74
74
74
74
74 .
74
74
74
74
74
78
200
205
195
185
167
165
165
165
164
98
73
73
73
73
Thermocouple
No. 2
76
77
87
94
96
104
121
134
143
169
246
245
245
245
242
239
234
231
231
229
226
198
188
123
98
83
74
No. 3
76
77
79
82
90
112
160
197
217
228
251
255
253
250
248
247
242
240
240
238
231
222
216
174
145
119
101
50
-------
Table 11-6. TEMPERATURE HISTORY FOR RUN NO. 6
Time
(mln.)
0
1
4
5
5.3
6
8
11
13
14
17
18
20
21
30
36
37
38
38.4
39
40
41
42
44
47
50
No. 1
72
70
65
63
63
62
62
75
81
90
117
133
205
210
175
168
158
155
150
90
72
63
60
60
60
Thermocouple
No. 2
73
73
73
73
73
82
97
114
130
145
208
221
221
221
199
188
185
185
185
167
134
108
96
88
73
62
No. 3
73
73
75
114
126
145
183
180
206
214
238
243
240
238
218
208
203
203
202
195
182
171
165
140
108
80
51
-------
Table II-7. TEMPERATURE HISTORY FOR RUN NO. 7
Time
(min.)
0
3
6
7
8
19
22
24
26
27
30
40
51
60
70
75
80
81
88
89
95
96
97
98
99
100
106
No. 1
75
70
65
63
60
60
58
58
63
63
68
77
90
100
105
107
110
no
116
116
118
118
116
105
92
80
65
Thermocouple
No. 2
75
85
105
104
104
67
64
65
67
69
78
107
109
141
153
158
163
166
166
166
160
158
156
143
129
117
66
No. 3
73
77
108
108
108
83
79
77
77
78
93
126
145
159
167
168
168
165
163
162
158
157
156
152
149
142
72
52
-------
Table 11-8. TEMPERATURE HISTORY FOR RUN NO. 8
Time
(min.)
0
1
2
6
8
9
10
11
13
15
17
19
20
22
30
40
42
44
46
48
53
60
70
80
84
88
No. 1
72
72
72
70
68
68
65
62
62
62
62
62
58
58
58
58
58
58
58
58
63
65
70
75
75
75
Thermocouple
No. 2
74
94
103
103
103
103
no
114
114
111
106
106
102
997
76
55
52
52
50
50
56
64
73
78
80
82
No. 3
77
77
77
82
179
208
199
193
187
186
189
194
179
154
99
71
67
66
67
67
68
78
85
88
90
90
53
-------
Table 11-9. TEMPERATURE HISTORY FOR RUN NO. 9
Time
(min.)
0
1
2
3
4
10
11
14
15
17
20
30
40
50
60
70
80
82
Thermocouple
No. 1 No. 2
77
84
90
93
97
195
211
241
264
263
254
217
198
174
167
157
154
147
No. 3
77
79
93
99
106
201
212
245
250
257
251
222
205
190
179
171
163
162
54
-------
Table 11-10. TEMPERATURE HISTORY FOR RUN NO. 10
Time
(min.)
0
1
4
5
10
18
30
40
43.5
45
46
48
60
70
80
90
100
120
130
140
No. 1
72
65
65
62
65
75
88
115
130
140
210
208
174
152
141
128
124
110
106
103
Thermocouple
No. 2
73
66
61
63
75
91
121
175
235
266
262
261
231
213
198
186
176
158
149
143
No. 3
73
73
73
73
79
93
127
186
238
240
264
264
252
238
226
214
202
181
172
164
55
-------
Table 11-11. TEMPERATURE HISTORY FOR RUN NO. 11
Time
(min.)
0
14
20
21
22
24
25
26
27
29
30
31
33
39
40
42
45
50
55
60
66
71
78
88
No. 1
72
72
72
72
72
71
65
65
63
61
60
60
60
59
59
59
59
58
58
58
58
58
58
58
Thermocoupl
No. 2
72
72
72
72
72
72
72
72
77
72
72
72
72
72
71
70
69
63
62
62
62
62
60
58
e
No. 3
76
74
104
109
108
101
96
95
93
88
84
84
79
71
71
68
68
68
68
64
62
62
64
69
No. 4
82
82
73
73
83
103
113
117
122
134
137
134
137
121
119
113
112
115
112
98
79
73
78
77
56
-------
SAM
0 5 10
1
'
il j.
0 5 10
15 20 25 30 35
BAM
•
7AM
III
X tO° CENTIGRADE !
i i
i 6AM l'ii
'• ' i ' •
t I !
!
1 f ' ' ,' ' 1 i
'• : 5AM 1 i i
! ! ; ''
i
i ' ' i ; ' '
4AM
f t i 'i
: i ; ' ' X 10° CENTIGRADE !
, , | , i • j ! ! ; ;
| i ( 3 AM
1
1
; ' i
2AM
T
t
1AM
Illl
X 10° CENTIGRADE
Mill
Hill
MIDT
15 20 25 30 35
11 HW
40 45
' I !
r j i ;
1
;
i
I
i
i ! ,
j j
' ;
I
i j '
\
i 1 ^ i
| , ;
; i
i i
;
i
t* M ' ^
j
I t i
'
' ;
40 45
JL
Figure U-1. A typical result from a recorder at the initial contact of water for FBCR
(Thermocouple No. 1).
57
-------
9.0
8.0
7.0
6.0
> 5.0
4.0
3.0
2.0
1.0
0
g.o
8.0
7.0
6.0
5.0
4.0
3.0
ZO
1.0
0
LI
3334
rr
NOTE: The mV scales are displaced by
one unit to completely separate the curves.
J II
I
2.2 4 5
10
15
Time, min.
20
II I II I I
NOTE: The mV scales are displaced by
one unit to completely separate the curves.
I I I
I
40
50 52 55
Time, mm.
60
I I I I I I I I
8.0
7.0
6.0
5.0
4.0 3
<
3.0
2.0
1.0
2526 28 30 32
8.0
7.0
6.0
5.0
4.0 3
3.0
2.0
1.0
0
65
70
j K, 11~?' A tyP'03' result from a recorder at thermocouple positions No. 2 (bottom curve)
and No. 3 (top curve).
58
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APPENDIX III
PRECIPITATION AND EVAPOTRANSPIRATION AT
MORGANTOWN, WEST VIRGINIA
The curves and table on the next page are based on Reference 9. Compu-
tation of evapotranspiratlon is based on monthly rainfall. Annual evapo-
transpiration was 18.01 in. Annual precipitation was 40 in. Neglecting the
runoff, the net flux is the difference between the precipitation and evapo-
transpiration (e.g., 40 - 18.01 = 21.99 in.). Average flux for a month is
21.99/12 = 1.832 in./month.
In the test stand, water passes to the FBCR through the water holder.
2
The area of the 16 holes in the water holder is 16 in • If 1500 ml of water
passes through the 16 holes, the test is the equivalent of 14.54 cm of rain,
falling in an average of 3.12 months. Therefore, 1500 ml of water (corre-
sponding to a net flux of about 4 months) is needed to control temperature
rise for 1800 ml of FBCR below 170°F.
59
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o
O
CL.
V)
<
cc
I
LLJ
O
m
CC
Q.
6.0
5.0
EE 4.o
3.0
2.0
1.0
I
I
I
^PRECIPITATION AT
BUCKHANNON
-EVAPOTRANSPIRATION AT
MORGANTOWN
\
\
•»
I
_L
I
I
I
JAN
FEB MAR APR MAY JUNE JULY AUG SEP OCT NOV DEC
Month
Precipitation3
E vapotranspi rati on
aAdjusted precipitation at Morgantown = (55 ) x Precipitation at Buckhannon
blf (precipitation - evapotranspirationKO, net flux = 0.00
Net Flux
JAN
FEB
MAR
APR
MAY
JUNE
JULY
AUG
SEPT
OCT
NOV
DEC
3.7 in.
3.17
3.96
3.30
3.96
4.75
4.93
4.22
2.99
2.82
2.73
3.26
0.01 in.
0.06
0.61
1.93
3.49
4.84
5.52
4.93
3.46
2.06
0.68
0.05
3.69 in.
3.11
3.35
1.37
0.47
0.00b
0.00b
0.00b
0.00b
0.76
2.05
3.21
TOTAL 18.01 in.
60
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APPENDIX IV
MEMORANDUM: TEMPERAURE RISE RATE MEASUREMENT
j UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
INDUSTRIAL ENVIRONMENTAL RESEARCH LABORATORY
t>. t
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Measurements of Rates of Temperature Rise
Objective: The purpose of the measurements is twofold. The first is to
observe the maximum temperature and .the rates of the rises in
temperature of the Fluidized Bed Combustion/Sampling and
Analytic Test Rig Residues when water is added to the residues.
The second is to find a way of controlling the rates of the
temperature rises, i.e., the rates of hydration of the high
lime in the residues.
Apparatus: 6" x 6" x I1 Plexiglas column with five probe locations for
thermocouples and pressure taps along the height of the side
wall of the column (see sketch), a strip chart recorder, four
thermocouples (ISA Type K), a peristaltic pump, a thermometer,
several kinds of tubing and fittings and a vacuum pump.
Procedure: The procedure described below may be changed after some experi-
ments, but it is envisioned to follow the procedure illustrated
below.
1. Place coarse sand of 1/2" thickness at the bottom of
the column, the FBC/SATR residues of 9-1/2", then coarse
sand of 1/2" thickness on the top of the column. Obtain
the solid samples from the bottom residues of SATR. The
dry weight of the residues is to be measured before placing
the residues in the column. Also determine the water
holding capacity. The compaction of the residues is a
loosened compaction, placing from the edges toward the
center and keeping the thermocouple junction at the
center of the cross-section of the column as it is filled
with the residues.
2. The first four probe locations from the top are to be
used for thermocouples.
3. Distilled water will be poured in the coarse sand layer
to a height of 1/4" water initially.
4. Observe the maximum temperature from the recorder. Depending
upon the maximum temperature, either a falling head method
with increased water height or a sprinkle device will be
used. The maximum temperature on which one method depends
is the temperature at which Plexiglas is deformed (160°F).
The sprinkle device may be a perforated spiral tubing con-
nected to a pump. The pump will have a capability to
control flow rates.
5. If the observed maximum temperature is below the tempera-
ture of deformation, add 1/4" water to the coarse sand
layer until water infiltrates through the residue thickness.
62
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6. Measure the permeability of the residue in that condition.
7. When water is infiltrating, observe the movement of heat
generation with proper thermocouples.
8. Check if flow is channeling.
9. Repeat steps 5 through 8 with increased water height.
10. If the observed maximum temperature is above the tempera-
ture of deformation, the perforated spiral tubing should
be used to sprinkle water from the top of the column
at a calibrated flow rate. Go through steps 7, 8, 9,
with different flow rates.
11. Mix the bottom residues with flyash in a production ratio
of SATR and repeat the above procedures.
12. The conditions of the FBC/SATR, solid feed rates and other
operating parameters should be representative of usual
AFBC conditions when the grab sample is taken.
Results: It is expected to observe the following results:
1. The maximum temperature of the residues with supply of
water as the high lime undergoes the hydration process.
2. The rates of the temperature rise (heat generation).
3. Permeability at unsaturated conditions.
4. Permeability at saturated conditions.
5. A method of controlling the hydration process, or a recom-
mendation of slaking lime, then column operations.
Benefits:
1. Better understanding the characteristics of the AFBC/SATR
residues and AFBC residues.
2. Saving expenses and time from future column operations with
the AFBC residues.
Duration: Approximately 6-8 weeks.
Note: This experiment and the particulate control experiment will
be coordinated to use time effectively.
63
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PLEXIGLAS SQUARE COLUMN SKETCH
12
THERMOCOUPLE LEAD
WIRE HOLES
(All units are in inches)
64
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-600/7-79-223
2.
3. RECIPIENT'S ACCESSION- NO.
4. TITLE AND SUBTITLE
Heat Generation of Spent Bed Materials from Atmos-
pheric Fluidized-bed Combustion of Coal
5. REPORT DATE
September 1979
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Rhyne H. Kim
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
10. PROGRAM ELEMENT NO.
See Block 12.
INE825
11. CONTRACT/GRANT NO.
NA (Inhouse)
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Final; 1/78 - 4/79
14. SPONSORING AGENCY CODE
EPA/600/13
15.SUPPLEMENTARY NOTES Author Kim was on loan to EPA from the College of Engineering,
University of North Carolina at Charlotte, Charlotte, NC 28223. Contact either Kim
or lERL-RTP's P.P. Turner. Mail Drop 61. 919/541-2825.
16. ABSTRACT
The report describes an experimental investigation of the hydration process
of spent bed material (with a calcium/sulfur ratio of 3) from an atmospheric fluidized
bed combustor for maximum temperature, rate of temperature rise, and controlla-
bility of temperature rise with various amounts of water. Tap water was supplied
through a rainfall simulating device. For the volume ration of the spent bed material
to water larger than 1.2, the temperature of the spent bed material rose to 77 C; at
ratios less than 1.2, the maximum temperature of the material was 132 C. Rates
of temperature rise in the uncontrolled hydration process were higher than those in
the controlled processes. The hydration process expanded the volume of the spent
bed material faster than by moisture in the atmosphere when the material was
exposed to the ambient atmosphere.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. cos AT I Field/Group
Pollution Hydration
Coal Temperature Con-
Combustion trol
Fluidized Bed Processing
Beds
Heat Flux
Pollution Control
Stationary Sources
Spent Bed Materials
Heat Generation
13B
21D
21B
13H
07A,13I
20M
07D
14B
3. DISTRIBUTION STATEMENT
Release to Public
19. SECURITY CLASS (ThisReport)
Unclassified
21. NO. OF PAGES
70
20. SECURITY CLASS (Thispage)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
65
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