United States
Environmental
Protection Agency
Industrial
Environmental
Research Laboratory-RTF
Combustion
Research
Branch
                                           EPA-600/8-77-O19
                                           December 1977

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Power
steelma
Big recipn
engines use
generate power
furnaces.
ustnal processes  like
 etining.  Gas turbines.
 :ernal combustion
 mp natural gas and
 /ommercial  and home
All of these ar^^^^pry sources of
pollution.  Thafl  j^Es noticeable  to
most of us as«           sources  of
pollution  as thJPHIind trucks we  see
on the street^vQ^M^.  But stationary
   rces are a major cause of every one
    e  six air pollutants identified by  the
    ronmental Protection Agency (EPA)
 s having  "potentiaf for wide-spread
adverse effects on human health
and welfare."
And  we are.  At the Industrial Environ-
mental Research Laboratory (IERL) in
Research  Triangle Park, North Carolina  -
part  of EPA's Office of Research and
Development -- a coordinated series of
programs  is under way to find the most
effective and economical ways of  con-
trolling pollution  from stationary sources.
                        33.7397
                                                                     PHOTOCHEMICAL
                                                                     OXIDANTS (SMOG)
                                                                     ARE NOT EMITTED
                                                                     DIRECTLY INTO
                                                                     THE AIR, BUT ARE
                                                                     PRODUCED BY THE
                                                                     REACTION OF
                                                                     NITROGEN OXIDES
                                                                     AND HYDRO-
                                                                     CARBONS IN THE
                                                                     ATMOSPHERE.
Like  other branches  of IERL-RTP, CRB
supports EPA's Office of Air Quality
Planning and Standards by supplying  the
technical information for setting realistic,
attainable standards  for pollutant emissions
from stationary sources.

But CRB's job doesn't  stop there.  By
finding cost-effective ways of controlling
pollution, CRB is helping utilities and
industries meet national air quality stan-
dards so that our air will be fit to breathe -
now  and in  the coming decades.  And  by
finding more efficient ways of burning fuel -
particularly coal -- CRB is making an
important contribution to conserving our
nation's supplies of fossil  fuels.

It's a big job.  There are  over 20,000
major stationary sources of pollution in  the
United States.  And  more are being built
every year to  satisfy our country's demand
for electricity and industrial products.  But
it's a job that  must be done  if we are to
have the kind of life we want for ourselves
and  our children.  And  it's a job that  can
be done --  with support from all of us
      ESTIMATED ANNUAL AIR POLLUTION FROM STATIONARY SOURCES - MILLIONS OF TONS
Much of this pollution -- especially
nitrogen  oxides, sulfur oxides, and par-
ticulates --  comes from  fossil fuel
combustion  - -  the burning of coal,  oil, and
natural gas.  Because of the growing
shortage of  oil  and natural gas,  more and
more power plants and  industries are
switching to coal,  a much dirtier fuel that
produces more of every  major pollutant.
This means that pollution from stationary
sources  will get worse in the coming
decades unless we do something about it
now.
                          Within IERL-RTP, the Combustion Re-
                          search Branch (CRB)  is playing a vital
                          part in this effort to improve the  quality of
                          our air in economically feasible ways.  The
                          focus of CRB's  programs is  on reducing
                          emissions of nitrogen  oxides, one of  the
                          most harmful  pollutants produced by
                          stationary combustion  sources.

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Today, almost 24 million tons of nitric
oxide and nitrogen dioxide (NOX) are
emitted  into our  atmosphere every year
from man-made sources.  About 55 percent
comes from stationary  sources  --  mainly
boilers,  furnaces, reciprocating internal
combustion  engines, and gas turbines.
Most of the remaining  45 percent is
emitted  m the exhaust  of highway vehicles.
Most NOX  is emitted from combustion
sources as nitric oxide (NO).  Once in the
atmosphere, much of this nitric oxide
converts to nitrogen  dioxide (NO2) -
pollutant with very dangerous effects on
human health
High concentrations of nitrogen dioxide
have been  fatal to miners, firemen, and
other workers.  Even at levels as low as  1
part in  1  million, nitrogen dioxide is  known
to be a cause of  respiratory diseases like
bronchitis and pneumonia --  especially in
children and older people.  Recent studies
have also linked low concentrations of
NOX with ozone depletion and high-nitrate
rains.   What's  more, NOX is one of  the
main components of photochemical smog
that ruins visibility in our cities and  irritates
the eyes and lungs of  millions of people
every year.

 In 1971, EPA  set a National  Ambient Air
Quality Standard for nitrogen  dioxide of 5
parts per hundred  million (100 micrograms
per cubic meter of air), annual average.
People exposed to concentrations of  N02
above  this  level run a  serious risk of
adverse  health effects.  Yet in the last few
years,  average annual  concentrations of
 NO2 have  exceeded the National Ambient
Air Quality Standard in  several of our
largest cities,  including  Los Angeles,
Chicago, Denver, New York,  and Salt Lake
City.
What's more,  unless more effective control
techniques are applied  nationwide, NOX
emissions are predicted to go even  higher
in the  next two decades.

One reason is that controlling NOX
emissions from mobile  sources has  proved
 to be more difficult than anyone antici-
 pated.  In  1970, a national emissions
 standard of 04 gram per mile for NOX
 from highway vehicles  was  planned to go
 into effect  by 1976  But the technology
 needed to meet this standard has turned
 out to be expensive, and it  lowers
 efficiency so that  most cars  get fewer
 miles per gallon
To conserve gasoline, EPA relaxed
the NOX emissions  standard for  mobile
sources to 2.0 grams per  mile for the
present.  And  Congress has agreed
that  a standard of 1.0 gram per  mile is  a
reasonable goal until at least 1983.  All of
this  means that more NOX will be emitted
from  highway
vehicles than
originally
expected.
                                                                                     ESTIMATED INCREASE IN ANNUAL NO, EMISSIONS FROM
                                                                                     STATIONARY AND MOBILE SOURCES WITHOUT MORE
                                                                                     EFFECTIVE NOX CONTROLS — MILLIONS OF TONS
 MOBILE
 SOURCES
STATIONARY
SOURCES
 At the same time, the number of power
 plants and industrial combustion sources
 in the United  States is projected to
 increase substantially between  now and
 the year 2000.  Most of  these new units
 will burn coal -- and hundreds of existing
 sources may  be forced to switch to coal
 as oil and natural gas supplies dwindle.
 As a result, NOX emissions from stationary
 sources could jump to 70 percent of the
 total  from  man-made sources by 1985.

 The  conclusion is clear:  NOX emissions
 from  stationary  sources  are going to have
 to be reduced substantially to keep  our air
 clean in the 1980's and beyond.

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To develop the technology we  need to
control NOx,IERL-RTP's Combustion Re-
search Branch is attacking NOX pollution
where it starts -- in the combustion
process itself.

Research  has  shown that NOX emissions
from combustion can be reduced by as
much as 75 percent by "combustion
modification" (lowering  the combustion
temperature, limiting the amount of  oxygen
available, and  regulating the  way the fuel
and air mix).   Combustion  modification
reduces the amount of NOX  that forms as
fuel burns.  This makes it an economical
and effective way to control  NOX com-
pared to  other techniques.

To find workable combustion modification
techniques for stationary sources. CRB
begins with fundamental research into the
basic chemical and aerodynamic mech-
anisms involved  in combustion.  This
research  is helping us  understand the
factors that cause NOX to form, and how
to control  NOX without  increasing emis-
sions of other  pollutants.

Along with fundamental research, CRB
also  sponsors  advanced research into new
low-NOx  designs for combustion equip-
ment, alternate fuels, and advanced
combustion concepts.   The ideas being
generated in this  research will  make it
possible to reduce pollution dramatically
and burn coal  and other fuels more
efficiently  10 to 20 years from  now.

The second major component of CRB's
program is pilot-scale  testing  Here, a
wide variety of combustion modification
techniques has been tried out under
controlled conditions in the laboratory.
The goal is to reduce NOX  without
causing operating problems, shortening
equipment life, or increasing emissions of
other pollutants.  Any technique that
passes the hurdle of pilot-scale testing
must also make  it possible  to burn fuel as
efficiently as -- or more efficiently than -
today's equipment.
                                PROGRAM OVERVIEW
programs are conducted in-house at IERL-
RTP laboratories  Others are being carried
out through contracts with  private com-
panies, grants  to universities, and coop-
erative agreements with the recently
formed Department of Energy (formerly the
Field demonstrations  are the last -- and in
many ways the most important -- leg  of
CRB's  NOX control program.  This  is
where techniques that look promising in
the laboratory  are evaluated on full-scale
equipment to make sure they can do the
job under actual working conditions.
During these demonstrations, emissions of
NOX and other pollutants,  as well as fuel
economy, are  carefully measured.  Any
adverse effects on equipment or operation
are also  noted.  The result is reliable
control technology that equipment manu-
facturers and users  can count on.

In all, CRB has  underway  more than 30
separate programs to develop  effective
and economical  ways of controlling NOX
They cover all the major types of
stationary sources in the United States,
from small home furnaces to utility boilers
that stand 10  stories high.   Some of these
   DEMONSTRATED7COST-EFFECTIVE
  COMBUSTION CONTROL TECHNOLOGY

 Federal Energy Administration and the
 Energy Research and Development
 Administration}.

CRB also  cooperates with owners and
manufacturers of combustion equipment
Most CRB programs are planned with
input from the combustion equipment
industry.  And CRB regularly tests
prototype equipment for  industry to deter-
mine the effectiveness of new designs in
reducing emissions of NOX and other
pollutants.

It's a systematic,  step-by-step approach  to
a complicated technical  problem  And it's
working.

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       47,8

These  giant boilers are  used by utilities
and industries to produce steam for  power
generation, manufacturing, and  dozens of
other industrial processes.  The largest  of
them can produce over 10 million  pounds
of steam an hour -- or over a  million
kilowatts of electricity -- more  than
enough energy to  supply a city of half a
million  people

Without controls, a  single coal-fired boiler
may emit up to 120 tons of NOX into the
atmosphere daily.  An estimated 6 million
tons of NOX are emitted every  year  from
utility and large industrial boilers in the
United  States  — almost half  of the NOX
from all stationary  sources combined.

Unfortunately,  unless emissions standards
for coal-fired boilers are tightened. NOX
emissions from utility and large industrial
boilers will almost  certainly increase.  The
present standard for large coal-fired  boilers
is 0.7 pound of NOX for every  1 million
Btu's of heat produced  — compared to 0.3
pound  of  NOX for  oil-fired boilers and 0.2
pound  for gas-fired units.  Because  more
and more utility and industrial boilers will
be burning coal in the years ahead,  NOX
emissions from these sources could swell
to 200 percent or  more above  today's
levels

All this points up the need for  a much
more stringent emissions standard for large
coal-fired boilers in the years ahead  But
before  a tighter standard can be enforced,
better  control  techniques are needed -
techniques that can reduce NOX without
corroding equipment or causing operating
problems.
That's why improving existing  control
techniques -- and developing new control
techniques -- for coal-fired utility and
industrial boilers is CRB's highest priority.

To improve current combustion modifica-
tion techniques,  CRB is conducting field
demonstrations of full-scale coal-fired
boilers with the cooperation of boiler
manufacturers  These tests have already
shown that properly  applied combustion
modification techniques can reduce  NOX
emissions by 40 percent to a level well
below the current emissions standard
Although long-term  tests are needed to
determine the effects of these techniques
on boiler performance, this is  a significant
step toward making  coal an environ-
mentally safe fuel for our  country to burn

Equally  important for the decades  ahead
are CRB's  pilot-scale tests of advanced
combustion modification techniques  for
coal-fired boilers   As part of  this program.
                                            new burner designs are  being developed
                                            that can cut NOX emissions from coal-
                                            fired boilers by as  much as 60 to 70
                                            percent.  This reduction  can be achieved
                                            without wasting fuel, damaging equipment,
                                            or increasing pollutants like carbon par-
                                            ticulates,  carbon  monoxide, or organics.  If
                                            all goes according to schedule,  these new
                                            low-NOX  burners will be demonstrated  in
                                            full-scale  boilers  by 1980  The  results of
                                            these  tests will help manufacturers of
                                            these  huge boilers build effective NOX
                                            controls into their equipment at  the factory,
                                            where it  can be  done economically.
Along with  better combustion modification
techniques to meet today's needs, NOX
controls are also needed for  the new fuels
that may be used  in the 1980's and
1990's — coal-oil  slurries, low-Btu gas
from coal, and waste fuels.  CRB's
research will help  ensure that these new
energy-saving technologies do not create
more  problems than they solve.

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Small industrial, commercial, and resi-
dential systems are those that generate up
to 100,000  pounds of steam per hour -
or up to 10,000 kilowatts of electricity,
They  are used in dozens of  industrial
processes,  and  they  produce steam or hot
water for many  commercial operations.  In
our homes, they're the boilers and
furnaces that supply  steam or hot air for
space heating.

By itself, no single small industrial,
commercial, or residential system produces
much of the total amount of NOX that
pollutes our atmosphere.  But  since there
are literally millions of these systems in
businesses and homes  in the  United
States, together they are a major source
of NOX pollution.  Today, these systems
emit more than a quarter of the NOX from
stationary  sources every year  - - over
4 million tons annually.
                                           EPA's Office of Air Quality Planning and
                                           Standards is developing  New Source
                                           Performance Standards for small industrial,
                                           commercial, and residential systems. To
                                           help  set these standards, CRB is mea-
                                           suring emissions from many different kinds
                                           of boilers and  furnaces all across the
                                           country.
At the same time, so that  businesses  and
homeowners  will be able to meet the  new
standards, CRB is exploring ways of
reducing  NOX emissions without increasing
fuel consumption.  Modifying existing small
industrial, commercial, or residential sys-
tems already in operation  is usually not as
cost-effective as incorporating  NOX con-
trols into  new  designs.   So the  main aim
of CRB's work is to spell out guidelines for
designing new equipment.

Pilot-scale tests and field demonstrations
on residual-oil-fired package boilers have
already shown that NOX emissions can be
reduced by as much as 50 percent with
new burner and boiler designs.   In
addition, tests on  both gas- and oil-fired
boilers have demonstrated  that  combustion
modification techniques  are also very
effective in preventing NOX from forming.
                                          Within the next few years, this new
                                          technology will be available  for boiler
                                          manufacturers to draw on in designing
                                          Iow-N0x equipment to replace older units
                                          now in the field.

                                          In related programs, CRB is working to cut
                                          NOX  emissions from stoker  coal-fired
                                          boilers.  Emissions from  different types of
                                          coal  have been measured, and CRB is
                                          now evaluating the operating problems
                                          involved  in switching  from eastern high-
                                          sulfur bituminous coal to western low-
                                          sulfur coal.
Also being  developed is a new residential
oil furnace  that burns fuel much more
efficiently and  reduces NOX  emissions  by
more than  70  percent compared to
furnaces now  in use.  It uses an
advanced burner and carefully matched
firebox to cut  both NOX and particulate
emissions.  A  preproduction  model has
been constructed and is  ready to be
tested  under normal  working conditions
in the  field.

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                                            Ox     : — ,„._.
Stationary engines include both large
reciprocating internal combustion  (1C)
engines and gas turbines.  Most of these
engines are used to pump  gas and oil
through pipelines or as  standby electrical
generators for factories, power stations,
hospitals,  and  other places where  depend-
able power is  essential.  Thousands of
these engines are in use today across the
country.  And  even though  they burn
relatively clean fuels like natural gas and
distillate oils, they produce 2-1/2  million
tons of NOX every year - -  almost 20
percent of the total from stationary
sources.
CRB's program for gas turbines is focusing
on advanced controls  like changing  the
method of fuel/air mixing and the
configuration of the combustor.  The goal
is to reduce NOx emissions by 75 percent
for clean fuels like natural gas and light
oils, as well as for dirtier fuels like heavy
oils.   Pilot-scale  tests are being performed
                                            on 12 new gas turbine combustor designs
                                            with built-in dry NOX control techniques.
                                            Based on  these tests, full-scale models of
                                            the two  most effective combustors will be
                                            built and tested in  the field  The  end
                                            result will  be guidelines  for designing
                                            industrial and utility gas  turbines with  lower
                                            emissions  of NOX.  carbon monoxide, and
                                            hydrocarbons.
                                            CRB  is also investigating ways  to reduce
                                            NOX emissions from large-bore recipro-
                                            cating 1C engines.   Both new and retrofit
                                            designs  for diesel and spark-fired engines
                                           are being studied.  The aim  of the
                                           program is to find ways of redesigning  the
                                           engine  chamber so that NOX emissions
                                           will be  substantially lowered  without
                                           increasing emissions  of carbon monoxide,
                                           hydrocarbons, or carbon particulates.  As
                                           with gas turbines,  the results of these
                                           studies  will be used to design new, more
                                           efficient 1C engines that emit less NOX
                                           and other pollutants.

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Cement kilns, woodbark boilers, open-
hearth furnaces, and oil-refining process
heaters are all  examples of industrial
process combustion.  These sources emit
nearly 400,000  tons of NOX into our air
every year - - or about 3 percent  of the
annual total NOX emissions.   This is a
small percentage compared to utility and
industrial boilers or  stationary engines.
                feSlLVstti1*  ,»>  >
                            * r    .  •
                            rl   "^r
Nevertheless, NOX pollution from industrial
process combustion is a serious problem
in some areas of the country where iron
and steel works, oil refineries, or other
heavy industries are concentrated.  For
this reason, NOX from industrial process
combustion is  one  of the targets of CRB's
program.
                                           As yet. no nationwide New Source
                                           Performance Standards  have been set for
                                           industrial  process combustion  -- mainly
                                           because of the thousands of different
                                           types of equipment that fall  into this
                                           category.  CRB, however, has recently
                                           taken an  important  first  step by measuring
                                           emissions  of NOX and other pollutants
                                           from all major industrial process com-
                                           bustion sources, including the iron and
                                           steel, cement, aluminum, and  petroleum-
                                           refining industries.

                                           In some of these industries, afterburners
                                           are used to destroy pollutants --  espe-
                                           cially organic compounds -- formed in the
                                           combustion process.  However, recent
                                           research  has shown that afterburners
                                           sometimes actually create NOX as they
                                           destroy other kinds of pollutants.  In a
                                           program begun in 1977, CRB  is analyzing
                                           afterburner combustion  systems as  a first
                                           step toward developing  standards for
                                           controlling NOX without creating new
                                           environmental problems.

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CRB's programs in fundamental research
focus on the  two main  factors  in the
formation of NOX:  combustion chemistry
and combustion  aerodynamics.  Work in
the chemistry of combustion is answering
basic questions about the chemical reac-
tions that occur  when fuels burn, and how
temperature, fuel, and air affect these
reactions.  At the same time, research in
the aerodynamics of  combustion is exam-
ining the physical conditions in the flame
zone, and how different  ways of mixing
fuel and air alter these  conditions.
Although the primary purpose of these
studies is to increase knowledge of how
NOX is formed and  destroyed, CRB is also
exploring how combustion  chemistry and
aerodynamics affect other  pollutants,
including sulfur oxides,  hydrocarbons,
carbon monoxide, and organics   This
research is essential in understanding how
to  control NOx without  increasing emis-
sions  of other pollutants.

Thanks to fundamental  research, we  have
a much better understanding today of how
fuels burn, and of the intricate ways in
which the formation of  one pollutant
affects others  This understanding  is
already helping solve the practical prob-
lems of modifying the combustion  process
to  reduce NOX and  other pollutants.  By
knowing  more about how the combustion
process works, CRB has been able to
improve combustion modification tech-
niques and design  new, more efficient low-
NOx burners   Research into the basic
mechanisms of combustion will  continue to
play an essential part in controlling NOX
and other pollutants.

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As the need for more efficient ways to
produce energy continues to  grow, both
government agencies  and private industry
are developing  new technologies for
combustion processes.  CRB's advanced
combustion research programs ask basic
questions  about these new ideas at the
very beginning  of development.   Will  NOX
or other pollutants be formed in  the new
process?   Can  those  pollutants be
Controlled  economically?  How will controls
affect the  process7  Will it still operate
efficiently? Can it still be adapted to burn
different kinds of fuels?
                                          Answers to questions like these begin with
                                          theoretical studies.  Computer simulations,
                                          mathematical models, and good, hard
                                          thought identify problems with proposed
                                          new technologies, and suggest avenues
                                          that may  lead to  solutions.

                                          When  initial studies like these show that  a
                                          new idea  has promise, a second stage of
                                          research  begins.   In this stage, laboratory-
                                          scale experiments are conducted to  help
                                          researchers learn more about the basic
                                          principles of the  new technology.  CRB
                                          recently completed a laboratory-scale test
                                           of methanol (methyl alcohol) as a potential
                                           low-NOx fuel for small boilers and
                                           residential  furnaces.  Laboratory-scale
                                           investigations of combined-cycle com-
                                           bustion techniques and gas derived  from
                                           coal are now underway.
The results of these laboratory-scale
experiments pave the  way for the next
stage of advanced combustion research:
pilot-scale studies.  CRB's catalytic  com-
bustion program is in  this  important  stage
of development.   Materials like platinum,
palladium, and cobalt  oxide are being
tested in a pilot-scale facility for their
potential as combustion catalysts.  By
making it possible to burn fuel much more
efficiently at lower combustion temper-
atures, catalysts can reduce emissions of
NOX, carbon monoxide and  hydrocarbons
to very low  levels.  CRB's pilot-scale tests
have already found one catalyst that cuts
NO* emissions from a variety of fuels by
up  to 98 percent.

Decades from now, much of the energy
for  homes, businesses, and  industries may
come from new technologies like catalytic
combustion  --  techniques that are only
ideas today.  CRB's work in advanced
combustion  research  is helping to make
these ideas reality.

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Most  of CRB's programs zero in on very
specific pollution  problems for specific
kinds of combustion equipment.  But the
environmental assessment  is different.  It's
a program designed to put CRB's work  in
perspective by considering the larger
environmental and economic questions
raised in controlling pollutants from  sta-
tionary combustion  sources.

One goal  of this environmental assessment
is to evaluate the impact that controlling
NOX from stationary sources will have on
our environment, our economy, and our
supplies of energy.  What price will we
have  to pay to reduce NOX by 25  per-
cent?  By 50  percent?  By 75 percent?
How will  emission of other pollutants like
particulates, carbon monoxide, or hydro-
carbons be affected9 What level of
control can be achieved  without  causing
operating  difficulties and  wasting fuel?
Considering all the  ramifications, what is
the optimum level of control for each
major type of  equipment9

To get these answers, CRB is sifting
through a tremendous amount of informa-
tion on stationary sources,  pollutants,
controls techniques, and  environmental
effects.  In cases where  information is
lacking, field tests are being conducted to
gather data.

A second goal of the environmental
assessment is to  establish  the combination
of control  techniques that will  work  best in
each  of the nation's Air  Quality Control
Regions.   CRB is conducting systematic
analyses  of all factors that affect NOX
pollution in each of these  regions -- such
as population, the number and kinds of
stationary  and mobile sources, fuels
burned, wind and weather patterns,  and
topography.  These analyses  will help
each Air Quality Control Region set up a
realistic, workable strategy for controlling
emissions  of NOX and other pollutants
from sources under its jurisdiction.

CRB's  environmental assessment program
is an in-depth, 3-year study.  When it's
completed in 1979,  our country will  be in
a much better position to make intelligent
choices about controlling NOX in the
decades ahead.

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CRB's work is generating a tremendous
amount of new information on better ways
to  control  NOX  and other pollutants. To
share this information as widely as
possible,  CRB has an active technology
transfer program.  Its purpose is to bring
ideas and technical  information  to owners
and manufacturers of stationary source
combustion equipment,  as well as
thousands of  people in  related industries,
government, and universities.

The field  demonstration stage of CRB's
research  and development program is  one
part of this technology transfer program.
These demonstrations are carried out  in
factories  and  power plants in many
different parts of the country with the
cooperation of owners,  operators, and
equipment manufacturers.  They provide
an excellent opportunity for people in  the
field to get hands-on experience with  new
technology as it is being developed.

Along with field demonstrations, CRB also
sponsors  symposiums on stationary source
combustion.  Representatives from govern-
ment agencies, industry, and  universities
come together  to exchange  ideas and
discuss the problems of controlling NOX
and  other pollutants.  Papers are pre-
sented about current research sponsored
by CRB,  and about  the government's
strategy for regulating pollutant  emissions
These papers are published in the
proceedings of each symposium, and  are
available to the public.
Final reports on CRB's research pro-
grams --as well  as guidelines for design
and operation of combustion equipment -
get wide distribution through lERL-RTP's
Technical nformation  Service and the
National  Technical Information Service.  In
addition,  the results of these programs are
regularly presented at meetings of profes-
sional societies, such  as ASME, APCA, and
AlChE.
CRB also sponsors a  technical information
bulletin entitled  "NOX  Control  Review."
Published four times a year, the Review  is
one more part of  CRB's effort to spread
knowledge of the latest developments in
NOX control technology.  It now reaches
more  than 2000 readers in government
and industry.
                               .**  4

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CRB has already taken some important
steps toward making our air cleaner and
healthier to  breathe. Major accomplish-
ments  over  the last 2 years include:
• Combustion modification techniques  for
  coal-fired utility and  large industrial
  boilers that  reduce NOX emissions by
  40 to 50  percent with no adverse side
  effects.
• Pilot-scale tests of advanced pulverized
  coal burners for utility and  large
  industrial  boilers that lower NOX emis-
  sions by 70 to 80 percent.
• A residual oil  burner for small industrial
  boilers that  cuts NOX emissions by 65
  to 70 percent from heavy oils with high
  nitrogen content.
• An oil-fired home furnace that reduces
  NOX emissions by 70 percent without
  increasing carbon monoxide, hydro-
  carbons, or  smoke.
• Field tests proving that NOx emissions
  from small industrial  boilers can be
  lowered significantly  by  combustion
  modification techniques  and by firing
  methanol  instead of natural  gas or
  heavy  oils.
• Pilot-scale tests of an advanced
  catalytic combustion  system capable of
  reducing emissions of NOX. carbon
  monoxide, and hydrocarbons by as
  much as  95 percent.
A  great deal has been accomplished -
but there's still a great deal left to do.
Over the next 5 years, CRB will be
working to  achieve  three main goals.  One
of  these  is to  demonstrate  that the new
low-NOx pulverized  coal  burners now
being pilot-tested will  perform satisfactorily
on full-scale utility and industrial boilers.
This work is a critical part  of reducing
NOx pollution  in our air.  Large coal-fired
boilers already emit over 30 percent of all
IMOX from stationary sources.
And this figure could  jump  to over 50 per-
cent by the year 2000 without better
controls.  New low-NOx  burners should
make it possible to  cut NOx emissions
from coal-fired boilers by 60 to
70  percent.
Another of CRB's goals for the next  few
years is to significantly improve NOX
control techniques for small industrial and
commercial boilers and furnaces.  These
units emit only  7  percent of the  NOX from
stationary sources today.  But with
switching  from  oil and  natural gas to  coal,
this percentage is expected to skyrocket in
the next  10 to  20 years. To save time
and money, combustion modification tech-
niques already  developed and tested  for
large utility boilers will  be adapted to
smaller equipment, especially  stoker  coal-
fired boilers.
                                               ^**

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CRB's  third goal between  now and  1983 is
to demonstrate the  long-range effective-
ness of combustion modification tech-
niques by performance tests of a year or
more on coal-fired utility and large
industrial boilers in the field.  These tests
should show  us how to burn  coal more
cleanly and efficiently,  without increasing
operating problems  such  as corrosion,
fouling, and slagging.  As a result, many
coal-fired boilers that might have to  be
phased out for lack of adequate  NOX
controls may be  kept in  operation.  And
oil-fired boilers may be switched  to coal
without causing additional pollution
problems.
All three of these programs will play an
essential part in our country's switch from
oil and  natural  gas  to coal.  Unless we
have the technology to control  NOX and
other  pollutants to safe levels, energy
independence can only come at the cost
of a more polluted atmosphere.  With
CRB's help, we will be able to  take
advantage of our nation's supplies of
coal -- and keep our air clean and
healthy in the years ahead.
                                                                                      Prepared by Aerotherm  Division of
                                                                                      Acurex Corporation under EPA contract.
                                                                                      Photos courtesy of Aerotherm Division of
                                                                                      Acurex Corporation; Energy and  Environ-
                                                                                      mental Research Corporation; Pratt  and
                                                                                      Whitney Aircraft Group; Exxon Research and
                                                                                      Engineering Company; International  Flame
                                                                                      Research Foundation;  KVB, Inc.; Rocketdyne
                                                                                      Division of  Rockwell  International; U.S.
                                                                                      Environmental Protection Agency; and
                                                                                      Delaval Turbine Inc.

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