United States
Environmental Protection
Agency
Air and Energy Engineering
Research Laboratory
Research Triangle Park NC 27711
Research and Development
EPA-600/S9-84-025C Mar. 1985
£EPA Project Summary
Fourth Symposium on the
Transfer and Utilization of
Particulate Control Technology:
Volume III. Economics,
Mechanical Collectors, Coal
Characteristics, Inhalable
Particulates, Advanced
Energy and Novel Devices
F. P. Venditti, J. A. Armstrong, and M. D. Durham
Summarized herein is Volume III of
three volumes of proceedings of the
Fourth Symposium on the Transfer and
Utilization of Paniculate Control Tech-
nology held in Houston, Texas. October
11-15,1982. Volume III papersdiscuss
theoretical and applied aspects of
paniculate control technologies other
than fabric filtration and ESPs.
Volumes I and II are described in two
separate project summaries.
This Project Summary was developed
by EPA's Air and Energy Engineering
Research Laboratory, Research Triangle
Park, NC, to announce key findings of
the research project that is fully docu-
mented in a separate report of the same
title (see Project Report ordering in-
formation at back).
Introduction
The papers in these three volumes of
proceedings were presented at the Fourth
Symposium on the Transfer and Utiliza-
tion of Particulate Control Technology in
Houston, Texas, October 11-15, 1982,
sponsored by the Particulate Technology
Branch of the Air and Energy Engineering
Research Laboratory of EPA at Research
Triangle Park, NC.
The symposium brought together re-
searchers, manufacturers, users, govern-
ment agencies, educators, and students
to discuss new technology and provided
an effective means for the transfer of this
technology out of the laboratories and
into the hands of the users.
The two major particle control tech-
nologies—fabric filters and electrostatic
precipitators (ESPs)—were the primary
concern of the symposium. These tech-
nologies were discussed from perspectives
of economics, new technical advance-
ments in science and engineering, fun-
daments, and applications. Several papers
dealt with the interaction of sulfur dioxide
control and paniculate control. Additional
topic areas included mechanical collec-
tors, coal characterization, inhalable
paniculate matter, novel devices, and
advanced energy applications for panicu-
late control.
The symposium was conducted as a
series of parallel sessions, each containing
four to six related papers. The sessions
were scheduled to avoid conflict due to
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simultaneous sessions dealing with the
same topic. Each series of related sessions
represented a thread of technology. These
parallel threads, extending over the total
period ofthe symposium, provided a highly
integrated approach to the total subject of
particulate control technology, with
strands of specialized technologies. These
strands of specialized technologies, or
perspectives, provided the basis for the
division of the papers into three volumes,
each volume containing a set of related
session topics so as to provide easy access
to a unified technology area.
Volume III Papers
Volume III, summarized here, is a
collection of papers describing a variety of
aspects of particulate control including
economics, mechanical collectors, coal
characteristics, inhalable particulate mat-
ter, advanced energy applications, and
novel devices. Economic comparisons of
the costs of particulate control devices are
made in a series of papers. A section on
mechanical collectors describes theoreti-
cal and applied aspects of cyclones and
mist eliminators. The effect of coal char-
acteristics on the design and operation of
particulate control devices is also dis-
cussed. Several papers deal with a wide
variety of topics relating to inhalable
particulate matter including emission
factors, measurement techniques, source
emissions and fugitive emissions. The
application of particulate control devices
to nonconventional temperature and pres-
sure conditions is described in a section
on advanced energy applications. Most of
these papers deal with hot gas cleanup in
pressurized fluidized bed combustor gas
streams. Novel particulate control tech-
nologies are described in the final section.
Keynote Address
Particulate Control
Technology and Where
It is Going
K. E. Yeager
Electric Power Research Institute
This keynote address underscores the
key role of particulate control technology
in any practical strategy for reducing the
emissions associated with coal utilization.
Its importance results from the long-
standing and successful cooperative ef-
forts among user, supplier, and govern-
ment to achieve control methods which
are as reliable, simple and low cost as
possible. Opportunities are discussed for
capitalizing on this established and ac-
cepted base to solve the current and
emerging set of air pollution issues facing
the utility industry.
Second A - Economic
Comparisons
A Comparison of a Baghouse vs.
ESP's With and Without
Conditioning for Low Sulfur
Coal Applications
William H. Cole
Gibbs & Hill. Inc.
The new source emission standard of
0.03 lbs/106 Btu for electric utilities
suggests that the selection of particulate
removal equipment will increasingly favor
the baghouse as compared to conventional
ESP's for low sulfur coal applications. This
paper investigates a third alternative of a
relatively small ESP used in conjunction
with SOagas conditioning for newgener-
ating units, which typically require effici-
ency levels of 99.70 percent or higher.
The three alternatives are compared for a
500 MW unit burning low sulfur western
coal. Emphasis is placed on the compar-
able economics of investment, and present
worth of annual costs including fixed
charges, incremental energy, bag replace-
ment, sulfur feed stock, and maintenance.
Cost sensitivity is illustrated for assumed
escalation rates from zero to 10 percent. A
preliminary review indicates that ESP's in
conjunction with gas conditioning offer an
attractive alternative to a conventionally
sized ESP or baghouse, and may restore
the dominance of ESP's in equipment
selection.
Application of the Bubble
Concept to Fuel Burning
Sources at a Naval
Industrial Complex
Charles Thompson
Atlantic Division
Naval Facilities Engineering Command
Utilities, Energy and Environmental
Division
The Norfolk Naval Shipyard, Portsmouth,
Virginia, consists of a large Industrial
Ship Repair Complex. There are over 50
gas- and oil-fired industrial size boilers
located in the Shipyard. These boilers
serve such diversified functions as gen-
erating power, space heating, hot water,
and process steam and ship system
testing. Eight of these boilers exceed
Virginia's particulate emission limits by
as much as 90 percent. Engineering
studies outlined methods to achieve
compliance with Air Pollution Control
Equipment at a total cost of $9 million. A
change in the Virginia regulations for
particulate emissions from Fuel Burning
Equipment in 1979 allowed a Bubble
policy to be applied. This change allowed
a combination of Bubble concept and
control equipment techniques to be used.
The cost savings in applying this tech-
nique was approximately $6 million.
Discussed are the problems and proce-
dures in formulating an acceptable Bubble
concept policy and control program to
allow compliance for the boiler plants.
Section B - Mechanical
Collectors
Cyclone Performance:
A Comparison of Theory with
Experiments
John A. Dirgo
David Leith
Harvard School of Public Health
Department of Environmental
Health Sciences
This paper describes the results of tests
conducted on a Stairmand high-efficiency
cyclone. The cyclone was pilot plant scale
with a design airflow of 0.14 m3/s(300
cfm). Collection efficiency and pressure
drop were measured over a range of air
flows at ambient temperature and pres-
sure. An oil mist was used as a test
aerosol because it consists of spherical
drops of uniform density, which are
unlikely to bounce or re-entrain after
striking the cyclone wall. At each air flow,
a fractional efficiency curve (collection
efficiency vs. particle diameter) was de-
termined. Each experimental curve was
compared with fractional efficiency curves
generated by several cyclone efficiency
models. A comparison of this type is more
valid than one based on cyclone cut
diameter (the particle size collected with
50 percent efficiency). This work repre-
sents the initial phase of a study of
optimized cyclone design.
High Flow Cyclone Development
W. B. Giles
Mechanical Systems and Technology
Laboratory, Corporate Research and
Development, General Electric Company
Investigative studies of an atypical
cyclone configuration, designed for high
flow capacity, were performed, focusing
particularly on the design aspects of inlet
flow and dust disengagement. The results
indicate that a performance equal to or
superior to conventional design can be
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achieved with a net savings in cyclone
size and cost.
The design is characterized as a reverse
flow cyclone with both a large inlet and a
large outlet, plus increased engagement
length between the cyclone body and the
exhaust duct. Both of these features are
seen as means to suppress large scale
inlet turbulence. In addition, reduced
penetration is found by locating a vortex
shield in the base of the cyclone. The net
result indicates an approximate two-to-
one diameter reduction, relative to current
art, for equal flow capability and a slight
pressure loss penalty.
Cyclone Scaling Experiments
W. B. Giles
Mechanical Systems and Technology
Laboratory. Corporate Research and
Development, General Electric Company
A series of geometrically similar cy-
clones of conventional, high-efficiency
design was tested to assess the normally
accepted perception that cyclones act as
an inertia! collection device and therefore
can be scaled from model to prototype
size by an inertia! separative parameter.
These tests were conducted for three
different cyclone sizes of 4,12, and 36 in.
diameter over a range of inlet velocity and
at atmospheric pressure.
In using test dusts which had been
shown to have a low propensity for
triboelectric charging, good correlation
was observed.
Tests were also conducted using a test
dust which has been found to have a high
propensity for triboelectric charging. The
data does not correlate, has very high
efficiency, and is characterized by rela-
tively constant overall efficiency versus
cyclone flow. The latter behavior is noted
in several literature sources.
The critical user is, therefore, cautioned
in the acceptance of data unless, as a
minimum, the fractional efficiency can be
shown to correlate with the inertia!
separative parameter over a range in
velocity.
Test Methods and Evaluation of
Mist Eliminator Carryover
Vladimir Boscak
Atef Demian
General Electric Environmental
Services. Inc.
A test program was carried out at
GEESI's R&D pilot plant to determine
mist eliminator efficiency, carryover load
and droplet size distribution from a verti-
cal flow mist eliminator. The modified
EPA Method 5 was used to determine
efficiency and carryover load. The carry-
over load when the scrubber was operated
under standard operating conditions but
without mist eliminator washing was 28
to 60 mg/Nm3D (0.012 to 0.024 gr/
SCFD). When the bottom of the mist
eliminator was washed, the carryover
load above the washed section was 70 to
160 mg/N m^D (0.029 to 0.066 gr/SCFD).
Mist eliminator efficiency was greater
than 99%. A droplet photography tech-
nique was used to determine carryover
aerosol size distribution. The average
aerosol size measured above the mist
eliminator was about 100 to 200 microns.
Mist eliminator inlet size distribution
averages about 140 microns. The carry-
over is probably caused by re-entrainment
from the mist eliminator blades.
Section C - Coal Characterization
Filtration Characteristics of
Fly Ashes from Various
Coal Producing Regions
John A. Dirgo
Marc A. Grant
Richard Dennis
GCA/Technology Division
Louis S. Hovis
Air and Energy Engineering Research
Laboratory
Environmental Protection Agency
The filterability of fly ashes emitted by
coal burning power stations is described,
including that of several ashes generated
by low sulfur western coal combustion
that are best controlled by fabric filtration.
Chemical and mineralogical analyses of
the coals were examined to determine
possible relationships between coal and
ash properties and filtration behavior.
Both fly ash size and coal ash content
correlated strongly with the fly ash specif-
ic resistance coefficient K2. Weaker, but
discernible, correlations were shown for
electrical charge behavior and method of
coal firing. Coal sulfur content and ash
fusion properties and chemical structures
originally expected to influence particle
size showed no clear-cut effects on
filtration characteristics.
This paper has been reviewed in ac-
cordance with the U.S. Environmental
Protection Agency's peer and administra-
tive review policies and approved for
presentation and publication.
Fly Ash from Texas Lignite and
Western Subbituminous Coal:
A Comparative Characterization
D. Richard Sears
Steven A. Benson
Donald P. McCollor
Stanley J. Miller
U.S. Department of Energy
Grand Forks Energy Technology Center
As examples, we use two Jackson
group lignites from Atascosa and Fayette
Counties, Texas, and a Green River
Region subbituminous coal from Routt
County, Colorado.
The composition of individual fly ash
particles was determined using scanning
electron microscopy and electron micro-
probe, with support from x-ray diffraction
of bulk ash. Using particle sample popula-
tions large enough to permit statistical
treatment, we describe the relationship
of composition to particle size and the
correlation between elemental concen-
trations, as well as particle size and
composition distributions. Correlations
are displayed as data maps which show
the complete range of observed variation
among these parameters, emphasizing
the importance of coal variability.
We next use this data to produce a
population distribution of ash particle
resistivities calculated with Bickelaupt's
model. The relationship between calcu-
lated resistivity and particle size is also
displayed, and the results are compared
with measured values.
Use of Fuel Databanks for the
Effective Design of Steam
Generators and A QC Equipment
N. W. Frisch*
T. P. Dorchak
Affiliated Energy & Environmental
Technologies, Inc.
Information concerning coal properties
and their variability is critical to the proper
design of steam generators and associ-
ated gas cleaning equipment (precipita-
tors, FGD and, to a lesser degree, fabric
filters). For situations in which a fuel
source is well defined, a databank of
hundreds of coal and ash analyses may
be used to assess the variability of the
fuel and to develop critical sizing and
design parameters.
This paper discusses a comprehensive
computer approach which examines fuel
databank information and generates de-
sign parameters for a set of operating
conditions. Fuel parameters related to
*N. W. Frisch is with N.W. Frisch Associates, Inc., in
Kingston, New Jersey.
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boiler design and operation, including
fusion temperatures, 1250, fouling and
slagging indices, etc., may be entered or
generated for statistical analysis and
presentation. Uncontrolled and corrected
emission levels of particulate and SO2, as
well as acid dew point temperatures are
developed.
In the case of ESP's, the program can
indicate collection area requirements for
any type of emission rate (mass, concen-
tration or opacity basis). Gas conditioning
and pulse energization options are in-
cluded. Both statistical and a wide range
of graphical outputs provide the user with
desired guidance; a typical plot would be
a mine map with fuel or ESP parameters
overlaid.
Section D - Inhalable
Particulate Matter
Development of Inhalable
Particulate (IP) Emission Factors
Dale L Harmon
Air and Energy Engineering Research
Laboratory
Environmental Protection Agency
At the request of EPA's Office of Air
Quality Planning and Standards (OAQPS),
ORD is conducting a study characterizing
inhalable particle (IP) emissions from
various sources for the development of
emission factors.
Three contracts were awarded in
September 1979 to conduct source char-
acterizations for IP from major sources.
The testing phase for these contracts is
near completion, and individual reports
on the major sources which will include
the IP emission factors are being pre-
pared. The IP emission factors are based
on existing particle size data and the IP
source characterization tests. This paper
gives an overview of the EPA program to
develop IP emission factors.
This paper has been reviewed in ac-
cordance with the U.S. Environmental
Protection Agency's peer and administra-
tive review policies and approved for
presentation and publication.
Inhalable Particulate Matter
Research Completed by
GCA/Technology Division
Stephen Gronberg
Senior Environmental Scientist
GCA/Technology Division
GCA/Technology Division has com-
pleted literature surveys and stack tests
in order to develop reliable size-specific
particulate emission factors. The majority
of work concerned the iron and steel,
ferroalloy and iron foundry industries.
Particulate emission rates and particle
size distribution were measured at eight
facilities. Typically, tests were conducted
before and after a control device and only
in-stack techniques were used. The re-
sults of these tests and information from
other test programs have been reviewed,
ranked, and included in a Source Category
Report for each industry. The Source
Category Reports provide an updated
section of AP-42 "A Compilation of
Emission Factors" and present back-
ground information on industry trends,
engineering specifics and control devices.
This paper has been reviewed in ac-
cordance with the U.S. Environmental
Protection Agency's peer and administra-
tive review policies and approved for
presentation and publication.
Results of Testing for Inhalable
Particulate Matter at
Midwest Research Institute
H. Kendall Wilcox
FredJ. Bergman
John Scott Kinsey
Tom Cuscino
Midwest Research Institute
Source test data collected by Midwest
Research Institute for emissions of inhal-
able particulate matter have been pre-
sented in this paper for a variety of
industrial categories. Test results for two
cement plants (one wet process and one
dry process), one lime plant, and one
asphalt paving plant are available. Results
have been presented in terms of the AP-
42 format for the relative size fractions of
both controlled and uncontrolled emis-
sions from these processes. Such test
results should be of interest to control
device manufacturers as well as those
who may need to be involved in the
development of State Implementation
Plans for inhalable particulate matter.
This paper has been reviewed in ac-
cordance with the U.S. Environmental
Protection Agency's peer and administra-
tive review policies and approved for
presentation and publication.
Inhalable Particulate Emission
Factors Test Programs
Jim Davison
Acurex Corporation
The Energy & Environmental Division
of Acurex Corporation was contracted by
the Air and Energy Engineering Research
Laboratory (AEERL) of the U.S. Environ-
mental Protection Agency (EPA) to obtain
uncontrolled/controlled emissions data
from various stationary sources of air
pollution. The emission factors derived
from this data will assist in the deter-
mination of the need to set a national
ambient air quality standard for inhalable
particulate matter.
An extensive series of particulate mass
and particle size distribution tests were
conducted at several major sources,
including Kaiser Steel (hot metal desul-
furization and BOF), and Kennecott
Minerals (matte and slab tapping).
This paper presents a review of each
process, test equipment and procedures,
and test results expressed as emission
factors relative to process operations, and
as a percent of the particulate emissions
less than a selected micron size.
This paper has been reviewed in ac-
cordance with the U.S. Environmental
Protection Agency's peer and administra-
tive review policies and approved for
presentation and publication.
Characterization of Particulate
Emission Factors for Industrial
Paved and Unpaved Roads
Chatten Cowherd, Jr.
J. Patrick Reider
Phillip J. Englehart
Midwest Research Institute
This paper presents the results of an
expanded measurement program to char-
acterize uncontrolled particulate emis-
sions generated by traffic entrainment of
surface particulate matter from industrial
paved and unpaved roads. The emission
sampling procedure used in this program
provided emission factors for the follow-
ing particle size ranges: <15 //m, <1 O/OTI,
and <2.5 yum aerodynamic diameter.
Testing was performed at sites that were
representative of significant paved and
unpaved road emission sources within
the following industrial categories: crush-
ed stone and gravel processing; primary
nonferrous smelting; and asphalt and
concrete batching. Measured emissions
in each particle size range were correlated
with road and traffic parameters as a
preliminary step to the development of
predictive emission factor equations for
industrial paved and unpaved roads.
Previously collected field test data for
integrated iron and steel plants and
surface coal mines were also integrated
into the industrial road emission factor
data bases.
This paper has been reviewed in ac-
cordance with the U.S. Environmental
Protection Agency's peer and administra- i
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five review policies and approved for
presentation and publication.
Condensible Emissions
Measurements in the
Inhalablo Particulate Program
Ashley D, Williamson
Joseph D. McCain
Southern Research Institute
In order to meet the EPA's inhalable
participate program goal of obtaining
measurements of condensible matter in
process streams, a Stack Dilution Samp-
ling System was designed at Southern
Research Institute under EPA contract.
The principal component of the system is
a cylindrical dilution chamber in which
flue gas is mixed with filtered air and the
resulting aerosol-laden mixture analyzed.
As the sample is cooled by dilution,
condensible vapors form particles under
conditions similar to those which occur in
actual plumes. Field measurements have
been performed at a continuous drum mix
asphalt plant, two kraft recovery boilers, a
coke quenching tower, and an oil-fired
package boiler. Data from these tests
show that significant fractions of the total
emissions at some sources consist of
condensible vapors.
This paper has been reviewed in ac-
cordance with the U.S. Environmental
Protection Agency's peer and administra-
tive review policies and approved for
presentation and publication.
Section E - Advanced Energy
Applications
Gas Cleaning and Energy
Recovery for Pressurized
Fluid/zed Bed Combustion
Albert Brinkmann
Gottfried Bischoff GmbH & Co.
Peter Kutemeyer
Bischoff Environmental Systems
In an effort to reduce the consumption
of oil and natural gas the search for a new
technology, capable of utilizing low grade
fuels, as well as more fully extracting
available energy from high grade coal, led
to development of fluidized bed combus-
tion (FBC).
The advantages of FBC are:
A. Lower and more uniform combustion
temperatures, resulting in lower gen-
eration of NO,.
B. Acceptably low S02 emissions by
addition of limestone, thus elimina-
ting expensive desulfurization equip-
ment.
C. Smaller heat exchangers, and thus
smaller boilers, due to higher heat
transfer coefficients.
D. Use of low grade fuels.
The first operational FBC systems used
in Germany operated at atmospheric
pressure. These classic FBC plants re-
quired a relatively low capital investment
and presented no development problems
during installation or operation.
Demonstration of the
Feasibility of a Magnetically
Stabilized Bed for the
Removal of Particulate and
Alkali
L P. Golan
J. L. Goodwin
E. S. Matulevicius
Exxon Research and Engineering
Company
This Department of Energy sponsored
program is experimental in nature con-
centrating on evaluating the key factors
necessary for demonstrating the feasibil-
ity of this concept, viz., the ability of the
magnetic material to survive the PFBC
environment, and paniculate removal
efficiency operating at PFBC conditions.
The magnetic bed material evaluation
phase has been completed. The results of
the materials evaluation phase indicate
that coated cobalt particles are suitable
for this application. The particles have
been found to possess good oxidation and
attrition resistance while maintaining
magnetic properties at the elevated tem-
peratures. After 1000 hours of exposure
to FBC flue gas no mechanical failure of
the coating has been detected while
sample magnetization was reduced only
10-20%.
The test phase of the program has been
completed. The ficst phase of testing
determined filter media flow rates at
various field strengths. This was followed
by a series of tests to determine the gas
side pressure gradients at combinations
of filter media flow and field strength. The
final sequence of tests operated the filter
in the semi-continuous mode. While
these runs are still being analyzed, initial
data appears promising.
Test Results of a High
Temperature, High Pressure
Electrostatic Precipitator
D. Rugg
G. Rinard
J. Armstrong
T. Yamamoto
M. Durham
Denver Research Institute
University of Denver
The electrostatic precipitator (ESP) is
being considered as a final gas cleanup
device for pressurized fluidized bed com-
bustion (PFBC) combined cycle power
plants. In order to investigate the practical
feasibility of ESP's applied to high tem-
perature, high pressure (HTHP) gas
streams, a pilot scale unit has been
developed. This unit has been operated
over a spectrum of gas temperatures,
pressures, and dust loadings, which can
be encountered in PFBC systems.
The electrical characteristics of a wire
electrode and two electrodes designed by
Research-Cottrell are reported. Flyash
from the Curtiss-Wright PFBC was redis-
persed in the unit for these tests. The test
results are being used to quantify the
performance of HTHP ESP's and should
also provide needed information for other
PFBC gas cleanup devices which employ
electrostatic augmentation.
Coal-Ash Deposition in a
High Temperature Cyclone
K. C. Tsao
University of Wisconsin-Milwaukee
A. Rehmat
D. M. Mason
Institute of Gas Technology
Experimental evidence indicated that
the increase of paniculate removal effici-
ency in a high temperature agglomerating
cyclone is hampered by the formation of
cyclone wall deposits. The cyclone collec-
tion efficiency has been observed in a
laboratory hot cyclone to meet the desig-
nated performance when the temperature
of the dust laden gas is increased to near
its coal-ash fusion temperature. Factors
that are affecting the wall deposition
process are examined and estimation of
the relative importance of the operating
parameters are presented. A simple math-
ematical model for the wall deposition
mechanism is tentatively proposed. Ex-
perimental results on the occurrence or
absence of wall deposits will be dis-
cussed.
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Dust Filtration Using Ceramic
Fiber Filter Media—
A State-of-the-Art Summary
R. Chang
J. Sawyer
W, Kuby
M. Shackleton
Energy & Environmental Division
Acurex Corporation
0. J. Tassicker
S. Drenker
Electric Power Research Institute
Filter media suitable for use at temper-
atures of >1,000°F, employing ceramic
fibers in their construction, have been
under development for several years.
These filter media are intended for appli-
cation in the development of energy
production processes such as pressurized
fluidized bed combustion (PFBC), but will
also be suitable for many diverse indus-
trial processes. Ceramic media develop-:
ment work to date has shown significant
progress toward achievement of a com-
mercially viable high temperature filter.
Tests have shown that at high tempera-
ture, fine particles can be collected effici-
ently and pressure drop can be controlled
using pulse cleaning. Accelerated dura-
bility tests produce promise for long filter
life. More work is needed in durability
testing to detect application related prob-
lems and build the data base needed to
move this important product development
to commercialization.
High Temperature and Pressure
Paniculate Filters for
Fluid-Bed Combustion
D. F. Ciliberti
T. E. Lippert
Westinghouse Research and
Development Center
0. J. Tassicker
S. Drenker
Electric Power Research Institute
The only technological barrier to the
commercialization of Pressurized Fluid-
Bed Combustion (PFBC) is the efficient
removal of particulates at high tempera-
ture and pressure. The Electric Power
Research Institute has sponsored work at
the Westinghouse Research and Develop-
ment Center to investigate several filtra-
tion devices for this application. This
effort has included high pressure and
temperature pilot-scale testing of multi-
element ceramic bag filters of both the
woven and felted type. The current pro-
gram also includes screening testing of
high alloy sintered metal and tubular
porous ceramic filter candles at tempera-
tures in the range of 800-900°C and at
pressures of 11 atm. Subsequent to these
tests long duration life testing of a single
woven ceramic bag will be carried out to
optimize bag life with respect to cleaning
regimen.
Moving-Bed Ceramic Filter for
High-Efficiency Paniculate and
Alkali Vapor Removal at
High Temperature and Pressure
D. Stelman
A. L. Kohl
C. A. Trilling
Energy Systems Group
Rockwell International Corporation
A moving-bed ceramic filter for high-
temperature cleanup is described. The
concept employs a high-efficiency ceram-
ic filter that is cleaned continuously by
the slow downward motion of a thin layer
of granular material. Laboratory tests
have been conducted with a variety of
dusts carried in gas at temperatures up to
1500°F and at atmospheric pressure. The
observed particle removal efficiency from
a 1500°F gas containing 1 grain/scf of
1.6 micron median diameter particles
was found to exceed 99.96%. The pres-
sure drop across the filter was only 3.5 in.
of water at a gas velocity of 13 ft/min. It
remained essentially constant as a result
of the continuous removal of the filter
cake from the face of the ceramic filter by
the slowly moving granular bed. In addi-
tion to particle removal, the filter offers
the potential for alkali vapor removal
through the use of reactive getters in the
moving bed material.
Testing and Verification of
Granular Bed Filters for
Removal of Particulates and
Alkalis
T. £. Lippert
D. F. Ciliberti
R. 0. O'Rourke
Westinghouse Electric Corporation
The work described has been f u nded by
the Department of Energy (DOE) under
Contract DE-AC21-80ET17093.
The Granular Shallow Bed Filter (GBF)
is proposed as a device to clean particu-
lates from Pressurized Fluidized Bed
Combustion (PFBC) gas streams. The GBF
is a device in which the dust-laden gas
passes through a shallow granular bed,
depositing the particulate matter on the
surface of the granular media. The bed
medium is cleaned by a reverse flush that
gently fluidizes the bed and elutriates the
collected particulate matter from the
system. Described herein are analyses
and data that reflect on the GBF concept
as it would apply to a PFBC and prelimi-
nary results of testing done on a six-
element subpilot-scale GBF unit.
Results of systems analysis have shown
an overall economic incentive for the GBF
in PFBC compared to all-cyclone gas
cleanup. Based on this analysis, perfor-
mance goals for the GBF have been
identified. A six-element, 24-bed, sub-
pilot-scale GBF has been built and tested
at both ambient and simulated PFBC
conditions. Ambient flow tests were used
as a basis to characterize the backflush
system and evaluate candidate bed media.
At simulated PFBC conditions, the test
unit has been operated over 170 hours
(cumulative), through475 cleaning cycles
in three test phases. Test variables have
included bed media, filter flow face
velocity, backflush conditions, and dust
loading.
Baghouse Operation in
Georgetown University
Coal-Fired, Fluidized-Bed Boiler
Plant, Washington, D.C.
Victor Buck
Pope, Evans and Robbins, Inc.
David Suhre
Georgetown University
Since 1979, Georgetown University
has operated the nation's first commercial
sized, coal-fired, fluidized-bed boiler plant
for over 10,000 hours, utilizing a bag-
house for particulate emissions control.
In plant startup, the bags are first coated
with limestone dust by operating the
forced draft and induced draft fans to
fluidize the bed. This is followed by firing
of No. 2 fuel oil to preheat the boiler and
the limestone bed. Upon achieving 100
psig boiler steam pressure, coal is intro-
duced into the preheated bed and ignited
by the oil burner to initiate boiler opera-
tion.
The baghouse has proven to be an
efficient particulate collector. However,
excessive pressure drop across the bag-
house has proven to be an ongoing
problem. Various baghouse modifications
have been implemented and different
bags tested. This paper presents the
results of this operation.
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Section F - Novel Devices
Particle Capture
Mechanisms on Single
Fibers in the Presence of
Electrostatic Fields
M. B. Ranade
F.-L Chen
D. S. Ensor
Research Triangle Institute
L. S. Hovis
Air and Energy Engineering Research
Laboratory
Environmental Protection Agency
Fabric filtration, although simple me-
chanically, is a complex phenomenon. As
part of an effort to isolate the mechanisms
significant in fabric filtration, simple
experiments have been devised to evalu-
ate the effects of electrostatic fields on
particle capture. A series of experiments,
with charged and neutral particles with
various applied fields, were conducted to
determine the location of deposits on the
fibers. In particular, the location of the
attachment of the aerosol, with respect to
the direction of flow, was found to be
strongly dependent on the applied field.
The implications of these data, compari-
son to theory, and implications when
applied to fabric filtration are described.
This paper has been reviewed in ac-
cordance with the U.S. Environmental
Protection Agency's peer and administra-
tive review policies and approved for
presentation and publication.
Pilot Demonstration of
Paniculate Removal Using a
Charged Filter Bed
Paul H. Sorenson
Air Correction Division, UOP, Inc.
The concept of fine particulate collec-
tion in a gas stream using a highly porous,
charged fiber bed was first developed at
Battelle Pacific Northwest Laboratories
while studying the collection process by
charged spray drops. Laboratory testing
by Battelle using highly resistive, charged
submicron aerosols showed that extreme-
ly high collection efficiencies were possi-
ble by this process. Air Correction
Division, UOP, Inc., has undertaken a
program to develop the concept under
field scale conditions. A transportable
4000 cf m pilot plant was constructed and
installed on a slipstream of a lignite-fired
utility boiler at the outlet of an existing
precipitator. The collection efficiency of
the bed was monitored as a function of
bed face velocity, gas temperature, and
particle charge levels. This paper reports
the results of the program.
Pilot Demonstration of Magnetic
Filtration with Continuous
Media Regeneration
Carroll E. Ball
David W. Coy
Research Triangle Institute
A mobile pilot plant with a nominal flow
capacity of 3,060 mVhr (1,800 cfm) was
designed and built to evaluate the use of
high gradient magnetic filtration (HGMF)
for particulate emission control on an
electric arc furnace (EAF). A five-month
test program was conducted at George-
town Steel Corporation's plant in
Georgetown, South Carolina, to test the
performance of the HGMF. A 500-hour
long-term test was scheduled and later
changed in order to perform additional
characterization studies.
The pilot-plant collection efficiency was
less than expected for the stainless steel
wool matrix packed to a density of 1.5
percent by volume. The matrix was then
changed to an expanded metal, packed to
a density of 3.5 percent by volume, which
resulted in much lower pressure drop
measurements, but even lower collection
efficiencies. The expanded metal matrix
was then packed to a density of 6.0
percent by volume, which gave higher
collection efficiencies than the steel wool
and a slightly lower pressure drop.
During the field test operations, there
were no significant problems with the
HGMF mobile pilot-plant equipment.
The report describes the design and
construction of the continuous HGMF
mobile pilot plant, as well as some of the
background work in high gradient mag-
netic filtration done at RTI. The field start-
up and performance characterization of
the mobile pilot plant are discussed in
detail. The experimental data and data
analysis are given, as well as an economic
evaluation and comparison of the HGMF
with other particulate control devices.
This paper has been reviewed in ac-
cordance with the U.S. Environmental
Protection Agency's peer and administra-
tive review policies and approved for
presentation and publication.
Section G - Plenary Session
Novel Particulate Control
Technology
Senichi Masuda
Department of Electrical Engineering
Faculty of Engineering
University of Tokyo
A review of pulse energization and
precharging is attempted in view of their
inherently great potentials for particulate
control and the current controversies
around these two technologies. They may
provide three major advantages when
properly designed and applied. These are
"energy-saving," "back corona correction
for high resistivity dusts," and "perfor-
mance enhancement for medium resis-
tivity dusts." The physical backgrounds of
these technologies are examined with
special attention to the technical potential
nanosecond pulses. Different designs and
operation modes of these technologies
are discussed in consideration of various
application areas and dust resistivity
levels, with an intention to provide a
guide-line for correct use of these tech-
nologies.
U. S. GOVERNMENT PRINTINGOFFICE:1985/559 111/10803
-------
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Denver. CO 80210
Dale L. Harmon is the EPA Project Officer (see below).
The complete report, entitled "Fourth Symposium on the Transfer and Utilization
of Particulate Control Technology: Volume III. Economics, Mechanical Col-
lectors, Coal Characteristics, Inhalable Particulates. Advanced Energy and
Novel Devices," (Order No. PB 85-161 917/AS; Cost: $23.50. Set of three
volumes PB 85-161 883/AS;Cost: $95.50, subject to change) will be available
only from:
National Technical Information Service
5285 Port Royal Road
Springfield. VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
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U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
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Agency
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