United States
Environmental Protection
Agency
Office of
Reseach and
Development
Industrial Environmental Research
Laboratory
Research Triangle P.~'k. North Carolina 27711
EPA-600/7-77-013
February 1977
            EPA AND ERDA
            HIGH-TEMPERATURE/
            HIGH-PRESSURE PARTICULATE
            CONTROL PROGRAMS
             Interagency
             Energy-Environment
             Research and Development
             Program Report

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                       RESEARCH REPORTING  SERIES
Research reports of the Office of Research and Development, U.S.
Environmental Protection Agency,  have  been grouped into seven series.
These seven broad categories were established to facilitate further
development and application of environmental technology.  Elimination
of traditional grouping was consciously  planned to foster technology
transfer and a maximum interface  in related fields.  The seven 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

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 systems.  The goal of the Program
is to assure the rapid development of  domestic energy supplies in an
environmentally—compatible manner by  providing the necessary
environmental data and control technology.  Investigations include
analyses of the transport of energy-related pollutants and their health
and ecological effects; assessments of,  and development of, control
technologies for energy systems;  and integrated assessments of a wide
range of energy-related environmental  issues.

                            REVIEW NOTICE

This report has been reviewed by the  participating Federal
Agencies, and approved for publication. Approval does not
signify that the contents necessarily reflect the views and
policies of the Government, nor  does  mention of trade names
or commercial products constitute endorsement or recommen-
dation for use.
This document is available to the public  through  the National Technical
Information Service, Springfield, Virginia   22161.

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                                     EPA-600/7-77-013

                                     February 1977
              EPA  AND  ERDA

HIGH-TEMPERATURE/HIGH-PRESSURE

 PARTICULATE  CONTROL  PROGRAMS
                      by

   R.A. Kennedy, H.  Dhillon, and J.B. Truett

             The Mitre Corporation
                Metrek Division
            McLean, Virginia 22101
        Contract No.  68-01-3539, Task 4
          Program Element No.  EHE623
     EPA Project Officer: Dennis C. Drehmel

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

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

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                                   FOREWORD


     The U.S. Environmental Protection Agency (EPA) and the U.S. Energy Research
and Development Administration (ERDA) are engaged in research and development on
methods for removal of particulate matter from gases at elevated temperature and
pressure.   Success in this endeavor is important for reasons of health and ecology,
for protection of process equipment, and for energy conversion efficiency.  Some
of the advanced energy processes have excellent environmental potential.  Development
of these processes is especially dependent on solution of the particulate problem.
This document, describing the related EPA and ERDA programs, is part of the effort
to affect interagency coordination in. the continuing development work.
                                       iii

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                                   ABSTRACT
     This report describes and compares  current  projects  sponsored  by .the U.S.
Environmental Protection Agency  (EPA) and  the .U.S.  Energy Research  and  Develop-
ment Administration  (ERDA), relating  to  the  control of  particulate  matter in
fuel gas streams at  high temperatures (1000  to 2000 F)  and high  pressures
(5 atmospheres and greater).

     The purpose of  the description is to  document  each project  indicating the
sponsor, contractor, funding, project officer,1 duration,  milestones,  and  to
provide a narrative  statement of objectives  and  the -technology involved.   Project
descriptions are intended  to provide  a basis for identifying  any overlap  or dupli-
cation and to indicate .areas which are not addressed by either Agency.  Description
of these projects was obtained from documentation provided by the two Agencies
and from discussions with Agency contractor  representatives.

     The project descriptions and the discussion of possible  overlap  or omissions
which follow is organized  to consider particulate control in  the three  categories
of:  (1) particulate characterization and  aerosol mechanics,,  ,(2) instrumentation
and measurement, and (3) control technology  development.   Conclusions and recom-
mendations are reached .regarding the  questions of overlap and omissions,  and the
general subject ,of interagency -coordination.  Introductory material reflects the
respective roles of  EPA .and ERDA and  the rationale  and  options relating to parti-
culate control through hot ;gas cleanup at  .elevated  pressure.

     The overall .effort for control of •particulate  matter at  high temperatures
and pressure includes four proj-ects sponsored by ERDA and eight  projects  sponsored
by EPA.

     Comparison of the EPA and .ERDA .activities for  possible overlap and omissions
is summarized in the '.conclusions .which indicate  that there is little  evidence of
any 'overlap 
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                                   CONTENTS

Disclaimer	.......	ii
Foreword		••'	iii
Abstract	iv
Tables	.-..'.	-	vi
     1.  Introduction	    1
     2.  Conclusions	11
     3.  Recommendations	14
     4.  ERDA Projects	.;  .  .		15
     5.  EPA Projects	  .	31
     6.  Comparison of ERDA and EPA Programs	48


References and Bibliography •	   51

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                                    TABLES







Number                                                                      Page




  1    Typical Turbine Specifications	,	10




  2    ERDA High Temperature/Pressure Projects 	    16 •




  3    EPA High Temperature/Pressure Projects 	   32
                                         VI

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                                   SECTION 1




                                 INTRODUCTION







     The U.S. Environmental Protection Agency (EPA) and the U.S. Energy Research




and Development Administration (ERDA) are both engaged in research and development




on methods for removing particulate matter from fuel and combustion gas streams




at nigh temperatures ( 1000 to 2000 F) and pressures ( 5 atmospheres and higher).




However, the primary orientation of the two agencies' programs differ significantly.




     EPA's principal interests are to insure that human health and the environ-




ment are adequately protected from the adverse effects of particulate emissions,




and that technological methods are available for controlling such emissions to




acceptable levels.  From EPA's standpoint, such control technology does not




necessarily have to operate at conditions of high temperature and pressure (HTP),




although HTP operation may be more efficient and more economical.




     One of ERDA's principal interests in particulate removal from hot pressurized




gases relates to the capability of using such gases (produced by gasification or




combustion of coal and other solid fuels) to drive turbines and other equipment




without introducing the large thermal inefficiencies attendant to cooling and




depressurizing the gas for particulate removal at ambient temperatures prior to




combustion.  If the particulate-laden gas stream enters a gas turbine without




particulate removal, the resultant decrease in turbine blade life would probably




adversely affect the economics of operation.  Another of ERDA's primary interests




is insuring that the exhaust gas from the turbine and other combustion processes




meets emission standards for particulate matter.

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1.1  EPA Involvement in HTP Particulate Removal




     EPA's work on HTP particulate removal is part of its R&D program for :parti-




culate control.  The overall program includes assessment of the effects of pollu-




tants on human health and welfare; development of technological measures for




controlling the release of environmental pollutants; and monitoring and controlling




of the release of particulate matter into the environment.  Since a major portion




of man-made particulate pollutants are associated with energy conversion and




utilization facilities, EPA has focused its attention mainly on steam/electric




power plants '(among the various stationary sources of atmospheric pollutants)




and on the automobile (among mobile sources).   The present report 'deals only with




stationary sources.




     The current emission standards for fuel combustion facilities are. expressed




as pounds of particulate matter per million Btu of heat input.  The current




emission limit from new stationary sources is 0.1 pound of particulate matter




per million Btu of thermal energy released by combustion processes.  The ambient




air standard is imposed in terms of the concentration of "total suspended parti-




culate" per cubic meter of air.  Although the size distribution of the particulate




is not reflected in these standards, the health and environmental effects of




particulate pollutants are related to the size distribution as' well as the chemical




composition of the particulate.     Very fine particles can by-pass: the body's




respiratory filters and may produce adverse health effects by penetrating deep




into the lungs.  Small particles (0.1  to ly in size) also reduce the atmospheric




visibility.  In view of these characteristics of small particles, EPA is considering




the establishment of standards for fine particulate emissions and ambient concen-




tration.

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     Earlier EPA work has demonstrated that particulate removal to meet existing




emission standards for combustion processes can be accomplished by application




of available equipment to exhaust gases under the moderate temperatures and




pressures at the stack (end-of-system cleanup).  EPA recognizes, however, that




particulate removal can be performed, partially if not totally, within the energy




conversion system, and that within-system cleanup may be accomplished with greater




efficiency and less expense than end-of-system cleanup.  Such within-system parti-




culate removal may be performed with the gas stream at high temperature and




pressure, or at high pressure and reduced temperature.  One objective of EPA's




Particulate Control Program is to identify effective combinations of these three




approaches to particulate control:  removal at HTP, removal at high pressure and




low/moderate temperatures, and removal at the moderate end-of-system temperatures




and pressures.




     The requirements of improved thermal efficiency and equipment protection




have caused ERDA to concentrate on the monitoring and control of particulate at




high temperatures and pressures.  The success of these efforts can be expected to




reduce the requirements of control technology at the exhaust end of the gas turbines.




At this time, cyclones, electrostatic precipitators, and fabric filters are being




used effectively for removing particulate from gas streams at low to moderate




temperatures and pressures.  However, the control equipment has to handle very




large volumes of gases at reduced temperatures and pressures.  This consideration




is a major incentive for EPA's efforts in the area of HTP particulate control




technology.  In addition, the use of HTP clean-up systems would eliminate the

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problems of recovery of specific cor.-.pounds that could be combusted in the process




to form non-parti'culate pollutants.  These compounds include tars and oils




(high sulfur), ammonia, hydrocarbons, phenols, etc.




     EPA's interest in particulate pollutants is motivated by the undesirable




effects of particulate matter on the environment-  However, EPA recognizes that




any steps taken to reduce the concentration of particulate in fuel gas streams




within the fuel processing and utilization cycles will result in the minimization




of the cleanup effort needed at the point of release into the atmosphere.  The




interrelation between in-process cleanup and end-of-system cleanup forms the




basis for coordination between the particulate control activities of EPA and




ERDA.




1.2  ERDA's: Involvement in HTP Particulate Removal




     A major element in ERDA's mission is to enhance the utilization of domestic




fuel resources.  Toward' this end', ERDA has undertaken extensive programs for




producing synthetic fuel gases through the utilization of gasifiers and power




generation by fluidized bed combustors.  Innovative advanced power systems (combined




gas-steam turbine cycles, etc.) are being developed for efficient utilization of




these systems.  It is very desirable to maintain the pressure and temperature of




the fuel or combustion gas stream at high levels (pressures up to 1000 psig and




temperature upto 2000 F).  Despite significant improvements iri the' synthetic gas




production' process,- it is probable that the synthetic fuel gas from most of the




production processes will contain some suspended particles of various sizes.




     The equipment utilizing this fuel or combustion gas at high temperature and pres-




sure is generally a gas turbine.  Excessive concentrations of particulate tend to

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damage the blades of the turbine through erosion, corrosion and deposition.   The




efficiency of the turbine could decrease as a result of this damage.   Although




the size range, concentration, and velocity of particles that cause turbine




damage have not been established conclusively, particles larger than 2 microns (y)




in size appear to be more harmful than smaller particles.




     It is possible to clean up the fuel gas stream adequately at moderate




temperature and pressure by using the existing control technology for low




temperature/pressure operation.  Lowering the temperature and pressure of the




fuel gas stream lowers the thermal efficiency of the system.  Moreover, the




volume of gas increases when the pressure is decreased.  Therefore, the require-




ments of high termal efficiency, gas turbine protection, and the possibility




of cleaning a smaller volume of gas make it very attractive to employ control




technology that operates efficiently at high temperature and pressure.




1.3  Presentation and Categorization of EPA and ERDA Activities




     The objective of this report is to review the ongoing and planned activities




of EPA and ERDA pertaining to HTP particulate control, and to determine any overlaps




between these activities.  Since EPA and ERDA are operating relatively independently,




it is entirely possible that there may be some problem areas which are not addressed




by either Agency.  A number of such instances are identified in this report.




     Recognizing the potential benefits of high temperature/pressure particulate




clean-up, each Agency has undertaken RD&D efforts in this area.  ERDA's activities

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are generally ancillary to its efforts- deal-ing with  the  development  of  gas-if-ier.s'




and f-luid-lzed1 bed> combustors'.  EPA has initiated a- few maj.or  efforts concentrating




exclusively on the development and demonstration of  high temperature/pressure




particulate clean-up technology.




     The overall program for R&D in the high temperature/pressure  particulate




clean-up covers three major sub-areas.  These are:




     (1)  Particulate characterization and aerosol mechanics  (physical  and




          chemical properties, particle collection mechanisms);




     (2)  Measurement and instrumentation  (for observing mass and  volume concen-




          tration,, particle size distribution, and particle velocity)' for high




          temperature/pressure operation; and




     (3)  Control technology (particulate removal devices) for operation in




          high temperature/pressure gas streams.




     The ERDA and EPA activities are discussed in terms  of these categories in




Sections 4.0 and 5.0 of this report.  The rationale  for  the selection of. these




three activity categories is presented' in the subsections immediately following.




     1.3.1  Particulate' Characterization'.and Aerosol .Mechanics




     A- comprehensive' knowledge of the physical and chemical characteristics of




particul'ate at high temperature and- pressures is essential for developing




effective measurement instruments and particulate removal equipment  under these




conditions.




     Since ERDA's major incentive for the control of particulate at  HTP is




associated' with the: protection of equipment receiving, the- part"icle-l'oaded; gas




streams, the1 maj'or emphasis in ERDA programs is placed on the prevention of

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damage to turbines and other equipment by particulate matter.  Nevertheless,




the need for protecting the environment is also germane because of present




or future standards for particulate emissions.  It is possible that stringent




New Source Performance Standards may be established for the emissions of fine




particulate.  Some of these particulates may be the result of reactions in the




turbine which produce secondary particulate.  In addition, the constituents of




the fine particulate (too small to be considered harmful to turbines) may include




hazardous materials such as lead, mercury and arsenic.




     The preceding remarks highlight the need for comprehensive characterization




of the particulate content of fuel gas streams at high temperature and pressure.




This characterization will involve statements concerning the particle size distri-




bution, the chemical content of particles and the identification of gaseous com-




ponents which can be expected to transform into secondary particulate either in




the turbine, in the heat recovery and exhaust system, or after the exhaust gases




are released to the atmosphere.




     Characterization of the aerosol will provide an indication of the magnitude




of the HTP particulate problem in terms of (1) the potential damage to the power




generation equipment through erosion, corrosion, and deposition; and (2) the




expected impact on air quality of the particulate emissions from the power




generation system, and the resultant effect on human health, the ecology, and




esthetics.  A detailed knowledge of the magnitude and the nature of the HTP




particulate control problem can be significant in the development of an




effective control strategy for preventing equipment damage and evironmental




quality deterioration while maintaining high energy conversion efficiency.

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     In the ^context of effectiveness of control  technology,  it  is  important  to




study the mechanics of particulate behavior under conditions involving  high




temperatures and -pressures.  Physical properties such as resistivity  of particles,




and phenomena involving thermal ionization and reentrainment need  to -be more




completely understood in order to optimize the utilization of the  .particulate




control technologies.




     The need for characterization of particulate at high temperatu-r.e and  pressure




did not arise.-until particulate control under these conditions  became a 'necessity




on account of advanced power systems.  EPA has already undertaken  significant




efforts dealing with measurement instrumentation and control technology develop-




ment for particulate at HTP.  However, the activities pertaining to the charac-




terization .of particulate under these conditions have not gained momentum.




     1.3.2  Measurement and Instrumentation




     In the development of .direct combustion systems involving -gas turbines,  it




is important to undertake -real-time monitoring and analysis  of  the particles  in




the f-uel gas stream to -record the mass loading (or volumetric loading)  and the




size distribution of the particles entering the gas turbine  at .high temperature




and pressure.  An evaluation of -the performance of HTP .particulate cont-rol-tech-




nology also requires a reasonably accurate measurement of the -par-t-ioulate  loading




and size distribution ;at the inlet and .outlet of the control equipment.




     In the vicinity of the turbine inlet, pressures as high as 500 psi and




temperatures ranging from 1000 F to 2000 F can be encountered.  In such severe




conditions, 'mechanical devices such as hot wire anemometers  either fail quickly

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or become inaccurate vrith the passage of time.  Instruments utilizing mechanical




sampling techniques perturb the volume being monitored, and affect accuracy of




measurement.




     The measurement methods used for collection of fractional efficiency data




are based on various procedures including inertial impaction, optical counting,




condensation nuclei counting and diffusion batteries.  Because of the severe




conditions associated with high temperature/pressure particulate control equipment,




techniques other than the optical counters are not very effective in measuring




equipment efficiency.




     1.3.3  Control Technology




     Although no specific standards have been set for allowable particulate loadings




for gases used for driving gas turbines, it is generally agreed that the lifetine




and performance efficiency of gas turbines can be increased by reducing the parti-




culate content of the gas stream (particulate larger than 2y are considered more




harmful than smaller particles).  As an example, some typical particulate loading




specifications are listed in Table 1.  Electrostatic precipitators (ESP), scrubbers,




and fabric filters have been successfully used for removing particulate from exhaust




gases at moderate levels of temperature and pressure, but not under HTP conditions.




Lowering the temperature and pressure of the turbine inlet gas stream for the purpose




of facilitating particle removal by using proven techniques would result in a large




loss of energy.  Therefore, it is highly desirable that the particulate removal be




carried out at high temperatures and pressures in order to maintain high thermal




efficiency of the fuel conversion processes (coal gasifiers,FBC, etc.).

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                   TABLE 1.  TYPICAL TURBINE SPECIFICATIONS
     Turbine Manufacturer
        Particulate Loading
        (Maximum Allowable)
  United Aircraft"3


  Westinghouse


  General Electric
  (for aircraft-type turbines)

  Brown Bovari


  ERDA*



  (*See PON FE-7,  Section 4.3)
0.8 pound/10  scf low Btu fuel gas
(or ~12 ppm)

0.03 percent (in fuel oil)
(or 300 ppm by weight)

30 ppm by weight in fuel gas
(10 micron maximum)

1-2 ppm by weight (in gases entering
turbine)

0.75 grains/scf (or-2.6 ppm by weight)
in 0-2P- range

0.001 grains/scf (or~ppb by weight)
in 2-6|JL range
     The increased prospective utilization of combined gas/steam turbine/electrical

generating systems, coal gasification and synthetic gaseous fuels has intensified

EPA's interest in HTP particulate removal technology.  The economic and operational

incentives for the utilization of HTP particulate removal technology (e.g.,

improved fuel utilization efficiency, combustion of some harmful compounds1, and

the need to handle a smaller volume of gaseous products make HTP particulate

removal appear attractive for EPA.

     Specific ERDA projects are described in Section A and EPA projects in Section 5.
                                      10

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                                      SECTION 2

                                     CONCLUSIONS


1.   Fo overlaps.

    There does not appear to be any significant overlap or duplication of the

    EPA and ERDA programs.  The relatively small size of the ERDA program provides

    little opportunity for duplication, in itself.

2.   Significant gaps exist.

    The combined EPA and ERDA effort on particulate control at elevated temperatures

    and pressure is not large (Average combined expenditures are less than $2

    million per year for contract effort).  Gaps or omissions in the combined

    activities are most evident in the characterization of particulates and the

    study of aerosol mechanics, both of which might be considered to be fundamental

    to the development of a strong information base for control technology.

3.   Both Agencies have a common interest in solving the overall problem of
    particulate control

    EPA's role in the control of particulate centers on potential harmful effects

    of the emissions while ERDA's orientation is directed at the protection of

    equipment employed in advanced energy systems and in increasing system efficiency.

    However, each Agency has a substantial stake in the other's main purview of

    responsibility.  The successful development of advanced energy systems will have

    an important bearing on future energy-related emissions.  In a similar manner,

    the health and ecological effects of these advanced systems must be environ-

    mentally acceptable if they are to be implemented.  Each Agency has an interest

    in the solution of the particulate problems that fall within the primary responsi-

    bility of the other.

                                          11

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    If any of these problems remain unsolved, there will be no advanced system




    nor will, the expected benefits in health, ecology, or energy self-sufficiency




    be realized.




4.  Increased interagency coordination is needed.




    The interagency interest in the particulate control problem will require




    continued coordination in these programs.  If the small size of the ERDA




    activities can be attributed to their recent inception, it may be expected




    to grow in the future.  New developments in the field of advanced energy




    systems may also stimulate this growth.  Increase in the attention given'




    to the particulate problem will require a corresponding need for increased




    coordination if programs1 are: to be efficiently planned without duplication




    and1 without serious omissions and if maximum use is to be made of the




    resulting technical data.




5.  Equipment protection requirements can be exped.itiously established.




    Determination of health and ecological effects may required substantial




    lead times due to the need for observations' covering long spans' of life.




    Equipment requirements, however,, may be ascertained more expedi'tiously.




    Determination of these equipment requirements would set a bottom limit




    which would narrow the field of consideration and allow concentration of




    effects study resources-^




6..  HTP parti'cu'lat-e cleanup.'not essential for meeting emission standards.




    Particulate' cleanup of hot pressurized gases is not an absolute environ-




    mental requirement.  Removal of offending materials at any point prior to




    discharge will satisfy environmental considerations.  Early cycle cleanup
                                         12

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    may be more efficient because of reduced volume and  may allow energy




    extraction which would not be practical otherwise.   Environmental  interest




    in the point of cleanup is a function of the efficiency of particulate




    removal,  along with whatever energy penalties may be avoided.   EPA's




    interest  in the hot pressurized cleanup technology is based upon the




    assumptions that advanced energy systems have a good potential for environ-




    mental advantages and that these systems will require early cycle  cleanup




    to avoid  unacceptable energy penalties or equipment  damage.




7.   ERDA does not have centralized programs for particulate control RD&D.




    Unlike EPA, ERDA's research and development activities are not organized




    around particular pollutants or pollutant control technologies. Consequently,




    there is  no centralization of responsibilities within ERDA for the control




    of particulates at high temperatures.  Unless a focal point is established




    and functioning at ERDA,  program coordination will require contact with a




    number of ERDA research and development offices.
                                       13

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                                      SECTION 3




                                   RECOMMENDATIONS






1.   Increase interagency coordination.




    Both EPA and ERDA will probably continue to pursue programs in particuTate




    control.  With growth of developments in advanced energy systems, the s'ize




    of this activity may increase from its present level.   Efficient planning




    of these programs will require close cooperation and coordination.




2.   Focus responsibilities for coordination.




    Due to the organizational structure of ERDA and the more immediate interest




    of EPA -in health and ecological effects, EPA may well be the more logical




    organization 'to take the lead and initiative in establishing necessary




    channels for coordination.




3.   Coordinate1future program plans.




    Interagency coordination in particulate control need not be limited to after-




    the-fact disclosures of program activities or the exchange of data.  Joint




    planning of future activities could include discussions and recommendations




    for assignments of particular developments.  Projects aimed toward filling




    identified gaps should receive priority attention.




4.   Facilitate technology transfer between agencies.




    In addition to the interagency coordination of activities discussed above,




    technology transfer should not be neglected.  Specific or special provisions




    for accomplishing this transfer is appropriate to any coordination discussions




    which are held.

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                                      SECTION A




                                    ERDA PROJECTS






     ERDA has five specific projects identified as addressing the subject of HTP




particulate characterization, measurement, or control.   These are identified in




Table 2 and summarized in the following sub-sections.   Specific projects are




described in a consistent format, insofar as possible from available information.




     In addition to these five specific projects, it should be noted that there are




many other ERDA programs associated with development of energy systems.   These programs




may include requirements for hot gas cleanup incident to operation of experimental




equipment.  The program descriptions which follow are those primarily devoted to




particulate control research and development.




4.1  Characterization and Aerosol Mechanics




     Of the many ERDA programs devoted to the primary objective of developing advanced




energy systems, several include particulate characterization tasks.  While these




programs have other primary objectives, the characterization activity is pertinent




to HTP particulate control.  This portion of the applicable programs is  briefly




described below.




     •  At Argonne National Laboratories some studies pertaining to chemical charac-




        terization of particulate in the combustion gases generated by a coal fired,




        pressurized FBC are being undertaken.  This characterization work is done




        incident to the evaluation of the effects of operating variables in the bench




        scale plant on response variables in the flue gas, including particulates.




        Particulates are collected from two series cyclone separators, a sintered




        steel filter and a final bag filter.
                                        15

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              TABLE 2.  ERDA HIGH TEMPERATURE/PRESSURE PROJECTS
Title
Contractor
                                                          Funding
                                                           ($K)
Milestones
1.  Particulate Analysis
    Instrumentation

2.  Particulate Measurement
    in FBC Systems

3.  Centrifuge Gas Cleanup
    System

4.  ESP Development and
    Test

5.  Moving Bed, Granular-
    Bed Filter
                        Leeds & Korthrup           75

                        Spectron Development
                        Laboratories               17

                        Mechanical Tech-
                        nology, Inc.              151
                        Not Awarded

                        Combustion Power
                        Company
                                 1/77  Completion
                                12/76  Completion
                                 5/77  Completion

                                 1/77  Contractor
                                 Selection Expected

                                 12/77 Complete Phase I

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        Chemical characterization is oriented toward collecting data relating to study




        of additive entrainment under various operating conditions.




     •  The Exxon Research and Engineering Company is collecting characterization




        data in conjunction with its Miniplant (FBC) work.   This characterization




        work has commenced within the last twelve months and has not yet been compiled




        in any of the papers describing Miniplant operation.  The data available to




        date is limited and reported only in the monthly reports submitted to the




        ERDA Fossil Energy Division sponsoring the FBC development.




     •  Work at the ERDA Morgantown Research Center includes atmospheric FBC develop-




        ment.  Particular attention is devoted to the combustion of  residual mining




        wastes not suitable for firing in conventional systems.  Various pulverized




        coals are also being tested.  Chemical characterization data is being developed




        in conjunction with the FBC operation.  This characterization is not intended




        exclusively to determine the character of the process off-gases, as the particle




        composition is also indicate of operating conditions such as combustion  effi-




        ciencies.




     •  At the ERDA Grand Forks Research Center,  data on particle resistivity




        is being acquired as a part of ESP operation studies.  Particle characteristics




        are also being studied within the Fluidized Bed Combustion Wet Scrubber Program.




4.2  Measurement and Instrumentation




     Recognizing the potential of measurement devices employing optical properties,




ERDA is currently undertaking two activities in this program area.  These projects




are described below.
                                        17

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PROJECT TITLE:  PARTICIPATE ANALYSIS INSTRUMENTATION FOR FLUIDIZED-BED
                COMBUSTION SYSTEMS

Contract Number:  E(9A9-18)-2412

Contractor:  Leeds and Northrup Company
             North Wales, Pennsylvania

Total Funding:  $106,200

Period of Performance:  May 1976 to May 1977

Sponsoring Division:  Office of Fossil Energy, ERDA

Project .Officer:  Mr. John Geffken

Purpose:  To examine the feasibility of monitoring equipment to evaluate

particle characterization in gas streams at high temperatures and pressures.

Objectives:

(1)  Adapt an existing measurement technique (low angle forward optical

     scattering) to the harsh fluidized bed combustion environment;

(2)  Calibrate and test the instrumentation at the Argonne National

     Laboratory's pressurized fluidized-bed combustion unit, followed by

     demonstration of the unit on the Curtis Wright small gas turbine unit;

     and

(3)  Evaluate the performance for potential commercial application.

Description of Technology:  This instrument utilizes a Leeds and Northrup

low-angle forward scattering technique instrument package for simultaneous

measurement of particle size and velocity.  This device will be directly

interfaced with a data sorter (mini-processor) to provide on-line  statistical

information, which can be used in a real-time mode or  stored for later  inter-

pretation.

                                         18

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     The measuring device will be developed to operate at temperatures in

the range 1,500 - 2,000 F, and pressures up to 10 atmospheres.  This package

is a potentially useful analytical tool for fluidized-bed combustion research

as an accurate on-line monitoring device for determining the efficiency of

particle filtering systems essential for the commercial deployment of PFBC

systems using gas turbine cycles.  In the program, special attention would

be focused on the quality and cleanliness of viewing windows under high

pressure, high temperature, high particle loads,  and a highly turbulent

gas stream.

Activities:   This project involves the performance of the following six

tasks during the period of performance.

Task 1:   Application Analysis and Instrument Optimization

Task 2:   Instrument Design and Manuals

Task 3:   Fabrication and Assembly

Task 4:   Check Out and Test

Task 5:   Installation and Training Support

Task 6:   Data Evaluation


PROJECT TITLE:  PARTICLE MEASUREMENT IN FLUIDIZED-BED COMBUSTION SYSTEMS

Contract Number:  E(49-18)-2413

Contractor:   Spectron Development Laboratories, Inc.,
             Costa Mesa, Calif.

Total Funding:  $17,219

Period of Performance:  April 1976 - December 1976

Sponsoring Division:  Office of Fossil Energy,  ERDA
                                  19

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Project Officer:  Mr. John Geffken


Purpose:  To examine the feasibility of an advanced diagnostic technique to make


particle  field measurements in fluidized bed combustion systems.


Objectives:


(1)  Test the capability of a Spectron Development Laboratories Particle Morphokine-


     tometer (PM) to obtain particle size and velocity measurements in the output


     train of a FBC at Argonne National Laboratories;


(2)  Determine operational limitations in terms of particle loading in the flow,


     light scattering outside the sample volume, and environmental limitations


     including window contamination, window  flange creep, and window deformation


     due to high temperature and pressure; and


(3)  Analyze acquired data by comparing particle size distribution and mass


     estimates with other available sampling techniques, and .estimated instrument


     sensitivity to variations in particle content.


Description of Technology;  The particle morphokinetometer involves the


mixing of two equally intense coherent light beams at an angle.  The inter-

                                             4          •            •
ference of the two beams produces a set of well defined equally spaced


interference  fringes.  The light scattered by a particle traversing the


fringe set is modulated according to the size and position of the particle.


The particle size is determined by the ratio of the amplitudes of the


modulated scattered intensity to the average scattered intensity.  The


signal time period is a measure of the particle velocity.
                                   20

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     Activities:  This project has the following milestones:

       -  design and installation of windows and flanges on the output train

          of a FBC at Argonne National Lab (ANL) (completed in October 1976)

       -  instrument operation for both cold and hot FBC flows for four weeks

          at ANL by SDL and ANL personnel (completed November 1976)

       -  report summarizing data and instrument evaluation by ANL and SDL

          personnel (due December 1976)

4.3  Control Technology

     The major projects in ERDA's high temperature/high pressure particulate

control technology effort are described below:

     PROJECT TITLE:  STUDY OF CENTRIFUGE GAS CLEAN-UP AND SEPARATION SYSTEM

     Contract Number:  E(49-18)-2428

     Contractor:  Mechanical Technology, Inc.
                  Latham, New York

     Total' Funding  $151,000

     Period of Performance:  May 1976 to May 1977

     Sponsoring Division;  Materials & Power Generation, ERDA

     Project Officer:  Mr. W. Fedarko

     Purpose:  To examine the feasibility of centrifuge systems for gas particu-

     late clean-up and gas constituent separation in coal conversion processes,

     with special emphasis on HTP operation of  centrifuges.

     Objectives:

     (1)  Determine the effectiveness and process economic advantages of centrifuges

          (alone or in combination with cyclones) for removal of particulates from

          the gas stream generated by coal combustion or coal conversion processes.
                                        21

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(2)  To evaluate the effectiveness and process economics of the centrifuges




     for separation of gas constituents is also an objective of this project.




(3)  To study the technical performances of centrifuges as a function of




     various operating conditions (flow rates, degree of purity, pressure,




     temperature, etc.) up to pressures of 1,000 psig, temperatures of




     1500 F, and flow rates as high as 200,000 scfm.




Description of Technology;  In this process, centrifuges will be utilized




for separating particulate from the low-Btu gas stream produced by a




gasifier.  In equipment to be tested, a centrifuge is combined  with




a cyclone for separating fluids of different specific gravities or for




separating suspended particles from a gas stream, by utilizing the centri-




fugal force generated by the rotary motion.




     The substitution of centrifuges for other methods of removing particu- .




late from high- and low-Btu gases should result in better separation factors,




thereby producing fuels of higher purity at lower costs.  Centrifuges are




more compact and require less energy than present particulate removal




facilities.  If the upper temperature and pressure limits and particulate




removal efficiencies are acceptable for the process clean-up, the centri-




fuge systems could offer an effective and economical alternative for HTP




particulate clean-up.




Activities:  In this project the following activities and time schedules




are planned:




(1)  Determine centrifuge capabilities in terms of flow rates, clean-up




     efficiency and reliability at high temperatures and pressures (to be




     completed in early 1977).




                                   22

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(2)  Scudy the process economics, including the initial and operating costs,




involved in employing centrifuges for particulate removal and separation of




gases at HTP (to be completed by (May 1977).




(3)  Study the effect of centrifuge  size, velocity, diameter, length,




     casing design, materials, method of suspension, drive, controls, and




     number of stages (series and parallel) on the technical performance




     and economy of centrifuge systems (to be complete in May 1977).




(4)  Prepare optimized conceptual designs of appropriate centrifuge systems,




     giving engineering details, expected performance, power requirements




     and estimated costs (to be completed by May 23, 1977).







PROJECT TITLE:   GRANULAR BED FILTER DEVELOPMENT




Contract Number:   EF-77-C-01-2579




Contractor:  Combustion Power Company




Total Funding:   $928,306




Period of Performance:  January 1977 - December 1977




Sponsoring Division:  Office of Fossil Energy, ERDA




Project Officer:   Mr.  John Geffken




Purpose:  The purpose of the first phase of this contract is to determine the




scientific and engineering principles upon which granular bed filteration




operates.  In particular, the granular bed filtration process will be analyzed




theoretically and evaluated.
                                   23

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Objectives:




(1)  To determine the scientific and engineering principles upon which granular




     bed filtration operates.




(2)  To predict the effects and inter-relationships of Granular Bed Filter  (GBF)




     design var-iables.




(3)  To predict the filtration performances of the GBF from a given set of design




     variables.




Description of Technology:  Combustion Power Company, Inc., was awarded a contract




to perform an intensive program to determine the scientific and engineering




principles upon which granular bed filtration operates.  The first phase of the




program will develop the theoretical analysis of the moving bed granular bed




filtration process and perform verification testing at ambient temperature.




Specifically, work will be performed on cold testing and mathematical modeling.




The cold flow facility will be designed with the provision for subsequent hot




flow testing.  If successful, the program will continue with & series of hot




mode tests, and construction and operation of a process development unit scale




MB-GBF to show its commercial applicability.  Subsequent phase (e.g. hot flow




tests) will be scheduled to insure that the GBF program continues on a timely




basis.  Hot gas cleanup is necessary for commercial application of pressurized




•fluidized bed combustion, GBF is one of the most viable contending systems.




Application -is also seen in coal conversion plants.
                                   24

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Activities:  This project involves the performance of the following seven tasks

during the period of performance.

Task 1.1  Theoretical Analysis of Granular Bed Filtration Process

Task 1.2  Calibration of Particle Sampling Equipment

Task 1.3  Dust Loading and Sampling Calibration Test Set-Up

Task 1.4  Cold-Flow Model Design

Task 1.5  Cold-Flow Model Test Set-Up

Task 1.6  Cold-Flow Model Tests for Design Variables

Task 2    Front Face Cleaning


PROJECT TITLE:  ELECTROSTATIC PRECIPITATORS DEVELOPMENT AND TEST OPERATIONS
                DEMONSTRATIONS  (PROGRAM OPPORTUNITY NOTICE)

Contract Number:  PON FE-7

Contractor:  Not yet selected

Total Funding:  Undetermined

Period of Performance:   Contractor selection  expected by January 1977.
                         No other details available at this time.

Sponsoring Division:  MERC (ERDA)

Project Officers:   Mr.  Charles Grua,  Mr.  Corell Shale

Purpose:  To develop and demonstrate by test operations, electrostatic

precipitators for particulate removal from gaseous fuels produced from

coals at temperatures in the range 1000 F to 1800 F and at pressures

ranging from one atmosphere to 450 psl.
                                    25

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Objectives:




(1)  To demonstrate by test operations an improved electrostatic precipitator




     capable of high temperature operation with acceptable collection efficiency.




(2)  To enhance the utilization of low-Btu gas as a substitute for natural




     gas by extending the state-of-the-art of purification methods., and




     to improve the efficiency of gas turbine or combined cycle power ^plants




     through the removal of particulates from low-Btu gas at high temperatures




     and pressures.




(3)  To demonstrate that improved ESPs can attain particulate removal effi-




     ciencies of 99.5 percent to 99.9 percent, and clean low-Btu gas such




     that it contains less than 0.75 gr/scf of particulate in 0-2 micron




     range, and less than 0.001 gr/scf in the 2-5 micron range.




Description of Technology:  The particulate loading specification for gas




turbines require a high removal efficiency for particulate in the size range




of 2p and larger.  . Electrostatic precipitators which operate very effectively




at moderate temperatures and pressures can be expected to be utilized success-




fully at high temperatures and pressures provided the desirable properties




of the .collection equipment and particulate can be maintained under these




severe conditions.  The ESPs have a low pressure drop, high efficiency for




small particulate, and possess the ability to handle both gases and vapors




for high volume flow.  The collected particulate can be removed easily..




     The steps in the electrostatic precipitation of particulate are:




       -  place a charge on the particle to be collected
                                    26

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-  attract the particle to the collector which has opposite charge,




-  neutralize the charge at the collector and remove the collected particle.




     At high temperatures, the particle resistivity may be low enough to




cause excessive reentrainment.  Also, the particulate may generate thermionic




emissions, thereby diminishing the charge on the particles, and a resultant




drop in collection efficiency may occur.  The material used for electrodes may




not be able to withstand the severe conditions...This may result in misalign-




ment of electrodes, non-uniform charging, and failure of the electrode material.




     If the problems listed above can be tested through the use of superior




design, improved material, and better operation procedure, ESPs may turn




out to be as effective at high temperatures and pressures as they are at




moderate levels of temperatures and pressure.




Activities:  This program will include the following activities (milestones




not, yet scheduled):




(1)  One or more improved versions of electrostatic precipitators will be




     tested in conjunction with a coal gasifier.




(2)  The precipitator design and characteristics will be improved until




     it is capable of displaying adequate particulate.removal efficiency




     at high temperatures (up to 1800 F) and high pressures (up to 450 psi).




(3)  The demonstration of the capabilities of an improved ESP 'for HTP




     particulate removal will be carried out in conjunction with a gasifier.




     This gasifier may either be owned by the contractor or be provided




     by the Morgantown Energy Research Center of ERDA.
                                    27

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PROJECT'TITLE:  WESTINGHOUSE SHOCK TUBE  (INACTIVE)




     The project described -below  is not  currently active and  consequently




not properly considered as a part of  the ERDA program.  Mention  is made




•here as a matter of convenience in the belief that it will be.of interest  to




.the reader.  The work completed, and  that which may be initiated in the  future,




could provide a significant contribution in establishing particulate require-




ments for turbine operation.




     The :project, recently completed  by  Westinghouse, was sponsored by the




ERDA Division of iFossil Energy under  contract E(49-18)-1514.  The work was




associated with Advanced Coal Gasification for Electric Power Generation




conducted July, .1975 through June, 1976.  This low^Btu gasification project




was done in conjunction with the Public  Service Company of Indiana.




     The Westinghouse'particulate study  objective was to define  the parti-




culate tolerance of turbine blades necessary for development  of  equipment




to be used in the low-Btu gasification process.




     Determination of particulate .tolerance is accomplished in an erosion




prediction 'process using-a combination of mathematical models and experi-




mental data.  A unique feature of the -technique concerns the  use of a shock




tube to produce .experimental data for the erosion and deposition-models..




The 'Shock 'tube provides for acceleration of measured amounts  of 'particulate




along with IDop.p'ler laser measurement  at  the point of impingement on the




test blades,  adjustable to various impact angles.




     The shock tube ^experimentation was  restricted to low temperature gas




streams.  However, the operators believe that heating the shock  tube may
                                   28

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     be controlled to produce an aerosol suitable for examination of gas streams




     in the 2000 F range.  While proprietary development is reported as continuing,




     the technique remains a possible condidate for future joint development.




4.4  General Comments on ERDA Programs in the HTP Particulate Removal




     ERDA's work in the area of HTP particulate control is oriented primarily




toward prevention of the damage that might be caused to the turbine by the parti-




culate which are allowed to enter the turbine.  Consequently, the measurement




techniques and particulate removal mechanism being developed, tested, and demon-




strated by ERDA are designed to address the particulate fraction which falls in




the 2p and larger size category, although it is recognized that the lower end




of the size range of particles that might damage turbine equipment is not yet




firmly established.  While it is entirely possible that some pollutants in the




vapor form might also cause damage to the turbine, the current efforts are




directed mainly at particulate control as a means for minimizing the erosion,




corrosion and deposition problems in gas turbines.




     The ERDA program does not currently include a substantial effort for charac-




terization of particulate matter found in the gas streams entering the gas turbine,




in terms of its chemical and physical properties.  However, an increase in character-




ization work is planned on completion of construction of those pilot plants which will




produce hot gas streams.  This characterization will be done as part of the operational




experimentation.




     In the area of measurement instrumentation, ERDA has two projects in progress.




These activities are aimed at the development, testing, and demonstration of




measuring devices using optical scattering techniques for in-situ installation.




Coupled with on-line data processors, these devices are capable of yielding





                                       29

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simultaneous measurements of particle size distribution, concentration and




velocity.  In terms of operating ranges, these devices cover temperatures up




to 2000 F and pressures up to 10 atmosphere.  The temperature parameter is




adequate for most anticipated uses, but the pressure range may be inadequate,




because ERDA is about to start testing and demonstrating particulate control




equipment at pressures as high as 1,000 psig.  Therefore, it would be desirable




to extend the pressure limit on the operation of these measuring devices.




     ERDA is currently engaged in testing and demonstrating the capabilities




of centrifuges and ESPs for particulate removal at high temperatures and




pressures.  In the absence of well-accepted specifications for allowable parti-




culate loading and size distribution for gas turbines, it is difficult to select




the most effective techniques for particulate removal at high temperatures and




pressures.  A knowledge of these specifications will also give some indication




concerning the impact of turbine exhaust gases on the ambient air (in terms of




particulate concentration).
                                        30

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                                    SECTION 5

                                  EPA PROJECTS


     EPA currently has eight active projects that address the control of particu-

late matter at HTP conditions.  These are identified in Table 3 and are summarized

in the following subsections.  It is noted that seven of the eight ongoing projects

are components of EPA's Particulate Control Program; the other is part of the

Fluidized Bed Combustion Program and is identified as such.

5.1  Characterization and Aerosol Mechanics

     In the past, EPA's major interest in the characteristics of particulate

matter has centered on the effects of such material on the environment and human

health.  Emphasis has consequently been placed on the characteristics of particles

in ambient air.  One study on the mechanics of aerosols at high temperature and

pressure was recently completed (August 1976) (Reference 2).  At present, EPA has

no active projects on particulate characterization at HTP conditions.

5.2  Measurement and Instrumentation

     EPA funded one project on measuring particulate parameters at HTP conditions

during FY 1976.  The original specifications of this project were as follows:
                                                          r

     PROJECT TITLE;  MEASUREMENT FOR HIGH TEMPERATURE/HIGH PRESSURE PROCESSES

     Contractor:  Acurex/Aerotherm Division

     Total Funding:  $ 90,000 (FY 76)
                     $120,000 (FY 77)
                     $ 70,000 (FY 78)
                     $ 25,000 (FY 79)
                     $ 25,000 (FY 80)

     Period of Performance:  October 1975 to October 1978
                                        31

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                                  TABLE 3.  EPA HIGH TEMPERATURE/PRESSURE PROJECTS
OJ
N3

Title
1. HTP Measurement
2. Hot ESP
3. HTP Filtration
4. Ceramic Filter
Materials
5. New Concept for HTP
Collection (Dry Scrubber)
6. Assessment of Granular Bed
Filter Technology
7. Granular Bed Filter
8. Collection Mechanisms
(Aerosol Mechanics)
Contractor
Aerotherm
Acurex
Cottrell
Environmental
Sciences
Aerotherm
Acurex
Westinghouse
Air Pollution
Technology
Air Pollution
Technology
Exxon
Research
Air Pollution
Technology
Funding ($K)
90 ;(FY-76)
120 '(FY-7?)
70 (FY-78)
25 '(FY-79)
25 (FY-80)
137 XFY-75)
284 (FY-76)
593 (FY-76)
240 (FY-75)
431 (FY-76)
140 (FY-76)
150 (FY-76)
300 (FY-77)
50 (FY-75)
300 (FY-76)

10/75
9/78
4/76
1/77
1/78
4/79
8/76
9/77
3/76
7/77
10/78
8/76
9/77
8/76
9/77
7/77
7/78
Phase
1/77
Phase
2/78
Milestones
Measure/Develop
Final Report
Define Stable T&P
Demonstrate Feasibility
Complete Pilot Scale
Complete Demo
Primary Evaluation
Verification
Demonstrate Feasibility
Complete Pilot test
Complete Demo
Primary Evaluation
Verification
Primary Evaluation
Verification
Complete System Study
Complete Demo
1 - Completed
Final Report
2 - Underway
Final Report

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Sponsoring Division:  Particulate Technology Branch, IERL-RTP, EPA




Project Officer:  Mr. William R. Kuykendal




Purpose:  This project is being conducted for the purpose of evaluation,




development, field testing and application research of high temperature,




high pressure measurement techniques necessary for HTP particulate control




technology development.




Objective:  The first technical objective of this project is to develop




measurement instrumentation needed for measuring the mass loading, size




distribution and velocity of particulate in gas streams at high temperatures




and pressures.




     The second objective is to develop measurement support for the evaluation




of particulate control technology being developed by IERL.




Description of Technology:  The technical approach being followed in this




project is similar to that adopted for the Method 5 particulate train.  This




train consists of a water jacketed probe which collects the sample and directs




it into a cyclone.  The cyclone is followed by an impactor, a filter, and an




impinger (for condensible products).  The outlet from the impinger is con-




nected to a pump which delivers the dried sample to a dry gas meter.




     In the first phase, technology development will concentrate on the




testing and demonstration of a short-term measurement system for particulate




and gaseous concentration.  The second phase will involve a three year




effort aimed at the development of an optimized measurement system for




particulate at HTP.




Activities:  The activities in the two phases of this program are described




below.





                                     33

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     Phase I

     Develop an acceptable measurement system 'for the measurement of pa-r-ticifiate-

     and gaseous concentration/composition data at high temperatures and  pres-

     sures (due for completion in October 1976).

     Phase II

     Develop an optimized system for the measurement of particulate and gaseous

     concentration/composition data at high temperatures and pressures  (due 'for

     completion :by October 1978).

5.3  Control Technology

     In fulfilling its responsibility to develop and demonstrate ;particulate

control technology, EPA is currently conducting the following projects 'that

address the control of particulate matter in HTP gas streams'.


     PROJECT TITLE:  DEVELOP HIGH TEMPERATURE AND PRESSURE ELECTROSTATIC
                     PRECIPITATOR .(ESP) '

     Contractor:  .Research Cottrell

     Total -Funding:  $137.,000 (FY 1975)
                     $284 ,.000 (FY 1976)

     Period of Performance:  April 1976 .to April 1979

     Sponsoring Division;  Particulate Technology Branch, lERL-RTP,, EPA

     Project Officer:  Mr. Leslie E. Sparks

     Purpose:  The purpose of this project is to determine the suitability of

     electrostatic precipitators for particulate cleanup at high temperatures

     and .pressures.

     Objectives:  There are two phases of this project, with the following.

     objectives:


                                       34

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Phase I




(1)  To define the temperature-pressure regions in which stable electro-




     static precipitator operation is possible.




(2)  To determine the temperature/pressure conditions in advanced energy




     processes, both for synthetic fuels and combustors.




Phase II




If there is sufficient overlap between the system (advanced energy pro-




cesses, synthetic fuels) requirements and ESP operating conditions, the




objective of this phase will be to develop high temperature/pressure ESP's.




Description of Technology:  EPA's major interest is focused on fine particu-




late removal, and there have been some doubts about the effectiveness of




ESP's in removing fine particles from the gas stream.  In the case of these




small particles, the main particle charging mechanism, "field charging"




makes up for the lack of diffusion charging in the case of particles which




are smaller than 1/2 micron.  Under moderate operating conditions (pressure




and temperature), the ESP's display minimum collection efficiency for




particles in the size range 0.1 to 1.0 microns.




Activities:  The activities involved in this project include the following:




(1)  Determine corona characteristics at temperature up to 2000 F, and




     pressures up to 500 psi in combustion gas and fuel gas environment.




     In particular, determine the impact of high temperature on particle




     resistivity, thermal ionization, re-entrainment and critical pressure.




(2)  Identify the temperature/pressure limits for stable ESP operation, by




     conducting batch operation of a single tube pilot precipitator.






                                          35

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(3)  Develop and operate a multiple prototype module in continuous operation
     mode.
PROJECT TITLE;  THE DEVELOPMENT OF HIGH TEMPERATURE. HIGH PRESSURE^PARTICLE
                CONTROL BY FILTRATION

Contractor;  Acurex Corporation/Aerotherm Division

Total Funding:  $593,000

Period of Performance:  August 1976 to August 1978

Sponsoring Division;  Particulate Technology Branch, IERL-RTP, EPA

Project Officer:  Dr. D. C. Drehmel

Purpose:  The purpose 'of this project is to support the development of

filtration as a technique for removing particulate from the high temperature/

pressure gas stream generated by gasifiers and combustion (pressurized FBC).

Objectives:  The following are the major objectives of this project.

(1)  To develop filtration procedures for ensuring that tihe gas turbines

     using ;gases generated by gasifiers and pressurized FBCs are protected

     from 'the suspended particles in these fuel gases.

(2)  To determine the •suitability of the filtration concept as an effective

     means for controlling suspended particulate at high temperatures and

     pressures.

(3)  To develop a'pilot scale HTP filtration device.

(4)  To carry-out an economic analysis of full scale filtration systems.

Description' of 'Technology;  Filtration is one of the most reliable techniques

for removing 'suspended particles from gaseous streams.  However, the severe

conditions represented by high temperatures and pressures require care'ful
                                    36

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consideration in the selection of materials and designs for filters to be




used in this environment.




     The most promising candidates for filter material are ceramics (silica,




alumina, zirconia,  etc.). which can be woven or felted into a gas filter.




Abrasion in weaves can be reduced by high temperature coatings and novel




weaving techniques.




Activities:  This project will be conducted in two phases.  The activities




in each phase are listed below.




Phase I - Preliminary Evaluation




(1)  Carry out theoretical studies concerning filter operations under high




     temperature and pressure conditions.




(2)  Select and obtain test materials for filters; design, fabricate and




     construct test apparatus.




(3)  Conduct experiments and collect data.




(4)  Analyze data and carry out an economic analysis of filtration as a




     means for HTP particulate control.




(5)  Conduct bench scale testing of the selected filtration system.




Phase II - Verification




(1)  Plan experiments for verifying the results yielded by Phase I.




(2)  Conduct experiments, collect data, analyze data and generate results




     pertaining to the validity of the indications yielded by the preliminary




     evaluation.
                                         37

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PROJECT TITLE;  DEVELOP CERAMIC FILTER




Contractor:  Westinghouse




Total Funding:  $240,000 (FY 1975)




Period of Performance;  March 1976 to October 1976




Sponsoring Division;  Particle Technology Branch, IERL-RTP, EPA




Project Officer:  Dr. D. C. Drehmel




Purpose:  To determine the suitability of ceramic filters as a means for




removing particles from combustion and fuel gases for the purpose of pro-




tecting gas turbines and the environment.




Objective;  The overall objective of this project is to develop and demon-




strate ceramic filters for removal of particulate matter from gas streams




at high temperatures and pressures.




     In the first .phase of this project, the objective is to demonstrate




the feasibility of using such filters under severe conditions represented




by high temperatures (up to 2000 F) and pressures (up to an undetermined




level).




Description of .Technology;   Cyclones (or centrifuge), scrubbers, ESPs and




fabric filters are the four particulate removal techniques in use at this




time.  Various design, material and .operational problems have resulted in




the first three techniques being relatively less successful in cleaning




HTP gases.  Fabric ,and bed filters have consistently shown acceptable levels




of performancejeven under extreme conditions.  Because,.of the [Severe opera-




ting environment, the selection of .a durable material for filters has been




a prime objective of researchers dealing the HTP control technology.





                                         38

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     Westinghouse has tested a ceramic filter developed by Horizons Inc.




The results have been satisfactory, in terms of collection efficiency,




operating reliability, and durability of the equipment.  Contrary to




original expectations, the pressure drop in the ceramic filter was not




very high.  Initial indications are that it would be feasible to use




ceramic filters for removing particulate from gases at high temperatures




and pressures.




Activities:




(1)  Demonstrate the feasibility of using ceramic filters for particle




     removal from gaseous streams at high temperatures and pressures




     (already completed).




(2)  Completed pilot tests involving the use of ceramic filters for




     removing particles from HTP gases (due March 1977).




(3)  Conduct a demonstration of a particulate clean-up system using ceramic




   '  filters (due for completion in October 1978).






PROJECT TITLE;  NEW CONCEPT FOR HTP COLLECTION  (DRY SCRUBBER)




Contractor:  Air Pollution Technology (APT) Inc.




Total Funding:  $431,000




Period of Performance:  August 1976 to August 1978




Sponsoring Division:  Particulate Technology Branch, IERL-RTP, EPA




Project Officer:  Dr. D. C. Drehmel




Purpose:  To develop an innovative technique for controlling fine particulate




at high 'temperature and pressure.
                                    39

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Objective:




(1)  To conduct theoretical and experimental studies aimed at the development




     of a new concept for fine particulate control at high temperature and




     pressure.




Description of the Technology;  The technology to be examined is a "dry




scrubbing system" for controlling fine particulate matter in a gas stream.




The system provides for contacting the fine particle-laden gas to be cleaned,




with large (diameter of 100^ or more) collector particles.  The collectors




(large particles) are introduced in a contactor unit consisting of a venturi




like device allowing injection of the collectors in the venturi throat.  Agglo-




meration of the fine and large particles will allow removal in a subsequent




separator designed for high efficiency removal of large particles.  A gravity




settler and virtual impactor are to be evaluated for the separation step.  The




system will be examined at the bench and pilot scales.   Regeneration and recycle




of the collector particles is planned as part of the system but is to be




evaluated independently of the bench and pilot demonstrations.  These demon-




strations will be operated at high temperature and low pressure in the expec-




tation that the impaction mechanism is not specifically dependent on pressure.




Collector particles to be used will include ash particles, large agglomerates




of fine particles, and metal beads.




Activities




     The technical objectives of the project will be completed in two phases:
                                  40

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Phase I:  Preliminary Evaluation of the Dry Scrubbing Concept




1.  Theoretical calculations of the mechanism of fine particle collection through




    use of relatively large particles (8/76 - 11/76);




2.  Bench scale experiments to evaluate the concept (8/76 - 3/77);




3.  Economic analysis based upon the theoretical calculations and bench




    scale experiments (2/77 - 4/77);




4.  Investigation of the energy and cost relationship as a function of temperature




    and pressure (3/77 - 5/77);






Phase II:  Verification of Fine Particle Collection




1.  Formulation of a verification test plan (5/77 - 8/77);




2.  Design of a 500 SCFM Model (6/77 - 12/77);




3.  Test of the 500 SCFM Model (12/77 - 6/77); and




4.  Economic analysis of dry scrubber operation based on data obtained in test




    of the Model (6/77 - 8/77).






PROJECT TITLE:  ASSESSMENT OF GRANULAR BED FILTER TECHNOLOGY




Contractor:  Air Pollution Technology (APT) Inc.




Total Funding:  $140,000




Period of Performance:  September 1976 to June 1978




Sponsoring Division:  Particulate Technology Branch, IERL-RTP, EPA




Project Officer:  Dr. D. C. Drehmel




Purpose:  To evaluate the existing granular bed filter systems for assessing




the suitability of this technology for particulate control at high tempera-




ture and pressure.
                                   41

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Objective:  The objectives of this project are:




(1)  To evaluate the status of  the current granular bed filter technology...




(2)  To assess the adequacy of  granular bed filters for meeting the parti-




     culate clean-up requirements of various advanced energy systems.




Description of Technology:  In  order to maintain high thermal efficiency




and protect the turbines  in advanced power systems, it is necessary to




remove the particulate from the gaseous fuel stream at high temperatures




and pressures.  Along with ESPs, fabric filters, and centrifuges, granular




bed filters offer the potential of effective and reliable service under these




conditions.




     Under other EPA projects,  there is performance data concerning existing




granular bed filters (including the Rexnord filter)•  These data indicate




relatively poor performance in  removing fine particles (1M- in size).  The




Combustion Power Company  (CPC)  granular bed filter not available for test




at this time.




     The assessment of the performance of various existing granular bed




filter systems will lead  to the development of engineering models and




design equations for predicting filter performance.  These systems will be




designed for operations at pressures up to 15 atmospheres and temperatures




up to 1100 C.




Activities;  This project is being conducted in two phases.  The following




activities are scheduled:




Phase I




Study the literature pertaining to empirical and theoretical information




concerning granular bed filters. (Due to be completed by September 1977).





                                   42

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Phase II

Carry out field sampling, and conduct detailed costs at two granular bed

filter installations selected as a result of Phase I study.  Determine the

effectiveness and characteristics of these two systems.  Prepare a final

report by June 1978.


PROJECT TITLE:  PARTICULATE CONTROL IN PRESSURIZED FBC-GRANULAR BED FILTER
                APPLICATIONS

Contractor:  Exxon  Research and Engineering Company

Total Funding:  $150,000 (FY 76)
                $300,000 (FY 77)

Period of Performance:  December 1976 to December 1978

Sponsoring Division:  IERL, RTF, EPA

Project Officer:  D. B.  Henschel

Purpose:  To design, develop and demonstrate a granular bed filter for

particulate clean-up of combustion gases produced by a pressurized,

fluidized coal combustion bed.

Objectives:  The major objectives of this project are:

(1)  To establish operational feasibility of granular bed filters under

     pressurized FBC operating conditions.

(2)  To optimize the performance, and measure the long-term effects asso-

     ciated with an expandable sand type granular bed filters.

(3)  To demonstrate the ability of granular bed filters to meet EPA

     emissions standards by cleaning fuel and combustion gases at high

     temperatures and pressures.
                                  A3

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Description of Technology:  In a pressurized FBC, the combustion gases are at




pressures up to 10 atmospheres and temperatures up to 1600 F.  The particulate




in the combustion gases must be removed before the gases go into a gas tur-




bine.  The system being developed by Exxon involves two stages of cyclones




followed by a Ducon granular bed filter between the FBC and the gas turbine




inlet.  Particles retained by the granular bed filter are periodically




removed by "blowing back" with compressed air.




Activities:




(1)  The installation of a Ducon bed filter is scheduled for completion by




     December 1976.




(2)  The filter will be checked out during the period December 1976 to




     May 1977.




(3)  The filter operation will be carried out over a 15 month period




     (May 1977 to August 1978).  During this time period, efforts will be




     made to measure the performance of the Ducon granular bed filter and




     optimize its particulate removal efficiency.  Maintenance of high removal;




     efficiency over an extended period of time will be an objective during this




     period.  The extension of equipment life will also be a target.




(4)  Starting in March 1977, an alternate HTP particulate removal system will




     be selected, designed and installed.  The checking out and operation




     of this device will be completed by December 1978.

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PROJECT TITLE:  EFFECTS OF HTP ON PARTICLE COLLECTION MECHANISMS




Contractor:  Air Pollution Technology (APT) Inc.




Total Funding:  $350,000




Period of Performance:  December 1975 to November 1977




Sponsoring Division:  Particulate Technology Branch, IERL-RTP, EPA




Project Officer:  Dr. D. C. Drehmel




Purpose:  To conduct theoretical studies of aerosol mechanics at HTP




followed by laboratory experimentation.




Objectives:  The objectives of this project are followed in two phases:




Phase 1




To determine the effects of temperature, pressure and particle diameter of




aerosols on various particle collection mechanisms, and to identify useful




collection mechanisms through theoretical studies.




Phase 2




To conduct laboratory scale experimentation to fill the gaps and reduce




the uncertainties identified in the theoretical study results produced in




Phase 1.




Description of Technology;  This project does not concern a particular or




specific technology in the sense that would apply to development of instru-




mentation or a collection or removal device.




     The project is intended to develop analytical techniques for studying




the high temperature and pressure aerosol mechanics which will in turn pro-




vide the data necessary for development of particulate control technologies.




These gas mechanics are imperfectly understood with the uncertainties







                                    45

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     representing a significant gap  in  the  capability to develop associated1




     measurement and control devices.




     Activities:




     (1)  Phase 1 has been completed'with a Final  Report scheduled in January'b/f:-(i9'7,7!.




     (2)  Phase 2 is underway with completion  scheduled  for November o'f I977 and; a'




          Final Report in February of 1978.




5.4  General Comments' on EPA Programs in the HTP Particulate Control Area




     Although EFA's interest in HTP  particulate control  is related only indirectly




to the development of .advanced energy systems  using  gasification or fluid'ized bed's,




the Agency has a strong interest  in  the development  of HTP particulate control




technology because of the potential  environmental  impact of the emi'ssiciris from ga's-




turbines and other energy conversion equipment.  EPA's major concern is to ensures




that adequate control systems are available at the time  needed  for applicatiioVi to-




new energy conversion technology.




     EPA considers it highly desirable  to have specifications for allowable




particle concentration and- size distribution- for gas turbines.   Such' specifica-




tions would make it possible for  EPA'1 and ERDA  to determine the  extent of commona-




lity that exists between ttieir respective requirements for HTP  particulate control




systems.  For instance,, the requirements for gas cleanliness for turbine- pro"t-ec-




tion are believed to depend on turbine  design'  arid  may be less: stringent than"1 for'




environmental protection.  Even if the  turbine specifications for total particul'ate




loading are more stringent than that for environmental protection, the emissions':
                                          46

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from turbines may include a high proportion of small particles (<2p) and the environ-




mental impact of these emissions may be disproportionately serious (relative to




total emissions).




     An attractive feature of high temperature/high pressure particulate cleanup




is the smaller volume of exhaust gases prior to combustion.   However, the severe




environment at the turbine inlet may result in low collection efficiency and




equipment reliability.  Therefore, a detailed cost benefit study should be performed




to evaluate the economics of HTP particulate clean-up as compared with particulate




removal under moderate conditions.




     EPA's current efforts in the area of HTP particulate control technology




development are principally concerned with filters, electrostatic precipitators,




and granular beds.  Cyclones and centrifuges are not being addressed by any of EPA's




ongoing projects.

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                                      SECTION 6




                         COMPARISON OF ERDA AND EPA PROGRAMS






     The preceding sections describing the Agencies' high temperature and pressure




particulate control activities are organized into the categories: of:




     -  Characterization and Aerosol Mechanics,




        Measurement and Instrumentation, and




     -  Control Technology




This same organization is employed in this1 comparison which is directed1 toward!




identification of any overlaps or duplication among the projects1 and discussion'.




of the gaps or omissions.  As will be noted, little if any overlap is1 detected,




while a comprehensive program coverage is yet to be achieved.




6.1  Characterization and Aerosol Mechanics




     6.1.1  Overlaps




     While EPA has recently completed one study of HTP aerosol mechanics and1 has




another currently under way,, neither Agency is; currently pursuing programs' for'




characterizing particulate matter in terms of chemical composition or size distri-




bution.  ERDA's work in this area is confined to whatever is- done incident to1,,




or as a part of, development work in advanced energy processes.  Thfsr report is




not inclusive of all such ancillary work which may have- produced characterization




data, or will in the future..  In the absence of specific characterization programs,




there is no evidence of overlaps except as! may or may not occur casually in the




advanced energy systems- research, development, and demonstration.
                                         48

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     6.1.2  Gaps

     Since EPA has a single current project on aerosol mechanics, and neither

EPA nor ERDA have current characterization projects, gaps in this area include

all necessary characterization and study of aerosol mechanics which has

not been completed.  Without attempting to enumerate all the potential gaps,
                                                     I
characterization of the hot gas streams from all promising gasification and

pressurized fluid bed combustion processes would seem to be likely candidates.

This would include data on physical and chemical characteristics of particu-

late matter and on aerosol mechanics up to 2000 F and 1000 psig; and for the

various fuels used by the advanced energy processes.

6.2  Measurement and Instrumentation

     6.2.1  Overlaps

     The EPA program does not include instrumentation test or evaluation which is

in any way similar to the two ERDA sponsored devices under investigation.   There

is no evidence of overlap or duplication.

     6.2.1  Gaps

     The collective instrumentation programs of EPA and ERDA includes only the

three devices described.   It seems probable that there are many more devices and

measurement techniques worthy of evaluation.   More specifically, two of the three

devices mentioned are designed for pressures up to ten atmospheres.   The need for

measurement of hot gas streams to 1000 psig will be required.
                                         49

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6.3  Contrpl; Technolog-ies.;




     6;. 3; li  Over-laps-,




     B,ot-h-. EPA\ and; ERDA; have; psriOj;ec.tss fore the; development- of"" hot: ESE"s'..  Noi ot-Ker,:




areas..,of. pptent-ial: duplication-, haye; been--, identiff±ed;!..




     Two.-, separate, programs  in the:-dieyelopmenb off electrostatic: precipitator.s?




do not  necessarilyv constitute, an- overlaps even- ifi the; devices^ are.' ihtendedi toi




operatef.on :.s-imi-larr hp.tt. gas;; str.eams.i, proyid.edj the;, pr.ecipitator,: mechanics^ or.'




technologyvdif f err significantly..  The. ERDA1^ program- is- in> the; procurement, stage,,




not - underr contract", ( and-j inf prmatlpn- regarding- detaiis--! off operation" iss not*:




ayailable,..  Cpnsequ,ently-j t whateyerj duplication -may exists between-- the?, two > pro?-




grams.,cannotrbe,»assessed^ at; thlsc




     6i3.2;;




     SeyenfOf f;thesprograms5jrepprted..-;h'ereiri-imay;'be« included; in-, the?general! cate=-




gory. of; control j.technolpgy|:deyelppment';, Th'e^ technologies?; inc'ludecelec-trostatlc"




pr.ecipitatprs,  _t granularrbed.jfilters5. ceramicf-materia-lsr,. aadry;.- scrubber- andr; a^




centrifuge... Gapsyin.nthisadeyelppmenti:and-ievaluation : includesthoseftpossible-;-




devices,jnptfbeing-cpnsidered.^anddthe,-:limitinggcharacteristicsMof; the^hbtigas'1




streamsiS;tp^wh.ich?vthef-.deyices2mighttbeaappliedri.  Penddrig?.;the<':suecesssaeh;Leved:i'*inr.




the. deyelppment; which ^issunderwayv. it fdoes.::nott appear ^ obvious;; that ^ any v specif icf.




areas ?ar,eebeingoneglected«attthisstime; . Theeeff6rt-and;-;attention;;beinggaccorded;s




the jprpblems <-p|5cpntrpl [technplpgy-/probablyyexceedsstheplevel I of f additipnal),wor-kt'




needed  in.cha;racter4-zatipn,i ^nstrument-ation}- .andcinj.'establishinggtheerequirements'*




fpr protect ion-of.; human ;.health,. ,the,--ecology-, ,^and 'equipment: which!:wi'll,';reeeiv.e*the--




hot gas .streams .-






                                           50

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                             REFERENCES AND BIBLIOGRAPHY
 1.  Dhillon, H. and H. Mahar.  Alternate Control Strategies for Fine Particles.
     The MITRE Corporation, METREK Division, (M76-76), August 1976.

 2.  Rao, A. K., M. P. Schrag, and L. j. Shannon.  Particulate Removal From Gas
     Streams at High Temperature/High Pressure.  Midwest Research Institute.
     EPA-600/2-75-020, August 1975.

 3.  Fulton, R. W. and S. Youngblood.  Survey of High Temperature Clean-Up Tech-
     nology for Low Btu Fuel Gas Processes.  Aerotherm Report 75-134, January 1975.

 4.  Perkin, H. C.  Air Pollution.  McGraw Hill and Co., 1974.

 5.  Whitby, K. T. and B. Cantrell.  Atmospheric Aerosols - Characteristics and
     Measuremental Sensing and Assessment.  Las Vegas, Nevada, September 1975.

 6.  Waggoner, ;A. P. and R. J. Charlson.  Aerosol Characteristics and Visibility.
     Final Report, EPA Grant // R-800-665, 1975.

 7.  Altshuller, A. P.  Principal Species in Atmospheric Fine Particulate Matter.
     Minutes of Meeting, EPA Air Pollution Chemistry and Physics Committee,
     Alexandria, Va., 1975.

 8.  Altshuller,, A. P.  Characteristics of the Chemical Composition of the Fine
     Particulate Fraction in the Atmosphere (Draft).  U.S. Environmental Protec-
     tion Agency* Research Triangle Park, N.C.

 9.  Hiddy, G. M.  Characterization of Aerosols in California, (ACHEX)...  Final
     Report to Air Resources Board, State of California, Vol. I-IV, 1974.

10.  Abbott, J. H. and D. C. Drehmel.  Control of Fine Particulate Emissions
     from Stationary Sources.  U.S. Environmental Protection Agency, IERL-RTP,
     Chemical Engineering Progress, December 1976, p. 47.
                                           51

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                                TECHNICAL REPORT DATA
                          (Please read Instructions on the reverse before completing)
1. REPORT NO.
 EPA-600/7-77-013
                                                      3. RECIPIENT'S ACCESSION-NO.
4. TITLE AND SUBTITLE
 EPA and ERDA High-Temperature/High-Pressure
    Particulate Control Programs
            5. REPORT DATE
             February 1977
            6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
                                                      8. PERFORMING ORGANIZATION REPORT NO.
 R.A. Kennedy, H. Dhillon, andJ.B. Truett
9. PERFORMING ORGANIZATION NAME AND ADDRESS
 The Mitre Corporation
 Metrek Division
 McLean, Virginia 22101
                                                      10. PROGRAM ELEMENT NO.
                                                       EHE623
            11. CONTRACT/GRANT NO.

             68-01-3539, Task 4
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;  6-11/76	
            14. SPONSORING AGENCY CODE
             EPA/600/13
is.SUPPLEMENTARY NOTES j.ERL_RTp project officer for this report is D. C. Drehmel, Mail
 Drop 61, S1S/54S-8411 Ext 2925.
16. ABSTRACT
          The report describes and compares current projects sponsored by EPA
 and the U.S.  Energy Research and Development Administration (ERDA), relating to
 the  control of particulate matter in fuel gas streams at high temperatures  (1000 to
 200'J F) and high pressures (5 atm and greater).  The descriptions document each
 project (indicating the sponsor, contractor, funding, project officer, duration,  and
 milestones) and provide a narrative  statement of objectives and technology involved.
 Project descriptions provide bases for identifying overlap or duplication, and indi-
 cate areas  not addressed by either Agency.  Descriptions were obtained from docu-
 mentation provided by the two Agencies and from discussions with Agency  contractor
 representatives.  Comparison of EPA and ERDA activities for possible overlap  and
 omissions is  summarized in the conclusions which indicate that there is little evidence
 of any overlap or duplication.  Since the composite effort of both Agencies is not
 large, some important areas of interest are not addressed.  No projects are dedicated
 exclusively to characterization and study of aerosol mechanics; however, one such
 EPA-sponsored study was completed recently. Some characterization work is done at
 ERDA, incident to advanced energy systems development. Development of instrumen-
 tation is limited and does not extend to the expected 1000-psig operating range.
17.
                             KEY WORDS AND DOCUMENT ANALYSIS
                DESCRIPTORS
                                          b.IDENTIFIERS/OPEN ENDED TERMS
                                                                   c. COSATI Field/Group
 Air Pollution
 Fuels
 Gases
 Particles
Air Pollution Control
Stationary Sources
Particulate Control
High Temperature
High Pressure
Fuel Gas Streams
13B
2 ID
07D
13. DISTRIBUTION STATEMENT

 Unlimited
19. SECURITY CLASS /This Report)
Unclassified
21. NO. OF PAGES

    52
                                          20. SECURITY CLASS (Thispage}
                                          Unclassified
                                                                   22. PRICE
EPA Form 2220-1 (9-73)

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