AP42 Section: 11.

6 Portland Cement Manufacturing

Title: Review of Proposed revision to AP-42 Section 8.6 (11.6, 5th edition)
Portland Cement

MRI

September 1980
Note: This material is related to a section in AP42, Compilation of Air Pollutant Emission Factors, Volume I
Stationary Point and Area Sources. AP42 is located on the EPA web site at www.epa.gov/ttn/chief/ap42/

The file name refers to the file number, the AP42 chapter and then the section. The file name
"rel01_c01s02.pdf" would mean the file relates to AP42 chapter 1 section 2. The document may be out of
date and related to a previous version of the section. The document has been saved for archival and
historical purposes. The primary source should always be checked. If current related information is
available, it will be posted on the AP42 webpage with the current version of the section.
 ,,r~o SF?,
AUG 1 0 1993
3
3 "$ UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
RESEARCH TRIANGLE PARK. NC 2771 1

OFFICE OF
AIR OUALITY PLANNING
AND STANDARDS

Mr. Robert W. Crolius

Vice President
DRAFT
American Portland Cement Alliance
1212 New York Avenue, N.W., Suite 500
Washington, D.C. 20005
Dear Mr. Crolius:
As you know, the Emission Inventory Branch of the
U. S. Environmental Protection Agency (EPA) is in the process of
updating the document Compilation of Air Pollutant Emission
Factors, Volume I: Stationary Point and Area Sources (known more
commonly as AP-42). As part of this process, we are now seeking
comments on the draft sections that are to be included in this
update of AP-42.
Chapter eight of AP-42 addresses the mineral products
industry and is one of the chapters being updated. Enclosed is a
copy of the draft Section 8.6, Portland Cement Manufacturing, and
the corresponding background report for the section. We would
appreciate it if you would distribute copies of the enclosed
draft AP-42 section and background report among your members for
review and send us your comments. Unfortunately, we are on a
very tight schedule, and it is important that we have all
comments by September 30, 1993 if we are to include a revised
Section 8.6 in the fifth edition of AP-42, which is scheduled for
publication this fall.
We appreciate the assistance provided by your organization
in compiling data for the 1991 revision to AP-42 Section 8.6, and
we look forward to your assistance in reviewing the enclosed
draft A P - 4 2 section. In preparing the enclosed background report
and draft AP-42 section on portland cement manufacturing, a
number of iBsues were raised that could not be resolved with the
information on hand. The following paragraphs describe the more
important of these issues. In order to make the fullest use of
the test data and other information available to us for this
revision, several assumptions were made about how the data should
be interpreted. We would appreciate your input on the validity
of these assumptions and on other information you can provide to
improve the draft AP-42 section.
 With few exceptions, the emission factors presented in AP-42
are based upon results from validated tests or other emission
evaluations that are similar to EPA reference test methods, and
revisions to the emission factors presented in AP-42 sections
must be supported with documented test results. At a minimum,
each emission factor in AP-42 is defined in terms of a unique
combination of emission source, pollutant, and air pollution
control device. As you can see from the enclosed background
report, approximately 80 emission test reports were reviewed in
the process of developing the revised draft AP-42 section on
portland cement manufacturing, and many of the emission factors
presented in the draft AP-42 section are based on several
emission tests. We are reasonably confident that the emission
factors based on several tests (ten or more) are representative
of the portland cement manufacturing industry. However, due to
the sparsity of data, the majority of the emission factors in the
enclosed draft AP-42 section are based on no more than five
emission tests. For many of these emission factors, we have no
reason to suspect that the data are not representative. However,
in a number of cases of emission factors based on a small number
of tests, there are inconsistencies in the data that cannot be
rectified using only the data presented in the individual tests
reports. In such cases, we would like your assistance in
identifying the likely reasons for these inconsistencies. If you
believe that some of the test data used in developing emission
factors for the draft AP-42 section should be excluded, we
request that you provide the engineering basis for excluding the
test results in question.
An example of apparent inconsistencies in test data is the
emission factor for SO2 emissions from long dry process kilns.
An average emission factor of 6.9 kilograms per megagram of
clinker produced (kg/Mg) (14 pounds per ton Ilb/tonl) was
developed from the data on long dry process kilns. (In the
current AP-42 section, the emission factor for SO emissions from
long dry process kilns is 3.5 kg/Mg [7.0 lb/tonl.f The revised
emission factor is based on the results of five emission tests.
The data in each of two of the tests (both conducted in 1977 on
two kilns at the same facility) resulted emission factors of 14
kg/Mg (28 lb/ton). The SO2 emission factors developed from the
other three tests averaged 2.1 kg/Mg (4.2 lb/ton), which is more
comparable to the SO2 emission factor for long dry process kilns
in the current AP-42 section and is likely a more representative
value. However, using only the information included in the test
reports, there is no basis by which we can exclude the 1977 test
data or average the results with the other test data in a more
appropriate fashion. Please suggest alternative methods for
handling these data that you feel would improve the estimate.
The C02 emission factors for the different types of kilns
are another example of inconsistencies between the data and
expected results. As energy efficiency increases, the C02
emission factor would be expected to decrease. However, the
emission factors for long, dry process kilns, dry preheater
process kilns, and dry preheater/precalciner process kilns are
essentially equal. Are these results reasonable based on your
understanding of the relative energy requirements of these
processes?
The issue of estimating SO2 emissions from portland cement
kilns also has been the subject of controversy for several years.
Our understanding is that the magnitude of SO2 emissions from
portland cement kilns is primarily a function of the sulfur
content of the fuel used to fire the kiln, the sulfur content of
the raw material, which varies enormously, and other operating
conditions. We would like your assistance in identifying how we
can evaluate material and process parameters to develop a more
reliable method for estimating SO2 emissions from portland cement
kilns. Please note that several of the emission test reports
reviewed for this revision to AP-42 included fuel sulfur
contents, as indicated in the background report. However, none
of the reports provided a chemical analysis of the raw materials,
and very little information is included on operating parameters
during the emission tests.
As is the case in previous versions of AP-42 Section 8.6,
the enclosed draft section presents kiln emission factors on the
basis of mass of pollutant emitted per mass of clinker produced.
However, many of the test reports reviewed provided process rates
on the basis of raw material feed only. In order to convert the
process rates from a feed to a production basis, the reports that
provided both feed and production rates were used to develop
conversion factors of 1.7 (feed to production) for wet,
preheater, and precalciner process kilns and 1.6 (feed to
production) for long dry process kilns. If your knowledge of the
industry indicates that these conversion factors are inaccurate,
we would appreciate your input on how we should convert raw
material feed rates to clinker production rates.
In the enclosed draft AP-42 section, emission factors for
criteria pollutants are provided for each of the four types of
pyroprocesses (wet, long dry, dry preheater, and dry preheater/
precalciner) for which data were available. However, because of
the sparsity of data and the relative consistency of emission
rates among different types of pyroprocesses, we developed the
emission factors for emissions of metals and organics by
combining the emission data on all types of kilns. We would
appreciate hearing your comments on the efficacy of this approach
to combining (or not combining) data on different pyroprocess
types. Any information'you could provide on which pollutants (or
groups of pollutants) are likely to be unaffected by type of
pyroprocess would be helpful; combining data from tests on
different pyroprocess types would increase our data base and
thereby improve the emission factors in AP-42.
 A final' issue that we would like to highlight concerns the
effects of fuel type on emission characteristics. In the
enclosed draft AP-42 section, we have not differentiated emi.ssion
factors by fuel type. The primary reason for disregarding fuel
type is that the majority of the tests documented were conducted
on coal-fired kilns, and the data on emissions from kilns fired
.with other fuel types (other than waste derived fuels) were
sparse and generally dated. As for waste derived fuels, the
available data indicate that emissions of metals and organic
pollutants from kilns fired with waste derived fuels are
comparable to emissions from kilns fired with conventional fuels
(coal, oil, and gas). However, until we can research this matter
further, we have decided not to include emission data from kilns
fired with waste fuels. Please comment on the need to provide
kiln emission factors by fuel type and your understanding of the
effects that different fuels types may have on emission
characteristics.
We appreciate your cooperation and look forward to receiving
your comments. If you have any questions, I can be reached by
telephone at (919) 541-5407 or by fax at (919) 541-0684.
Sincerely,

Ronald E. Myers
Emission Factors and Methodologies Section
Emission Inventory Branch
2 Enclosures
cc: Mr. Walter L. Greer
Mr. Mallory S. May

OAQPS/TSD/EIB:RMyers, rm 455B, 4201 Bldg., 541-5407, MD-14

(MRI/RMarinshaw/LKaufman/677-0249/08/06/93)
I !
 Review of Proposed Revision to AP-42,
Section 8.6, Portland Cement

Final Report

For U.S. Environmental Protection Agency

Office of Air Quality Planning and Standards

Contract No. 68-02-4395

Work Assignment No. 49
MRI Project No. 8987-49

September 30,1990

i MIDWEST RESEARCH INSTITUTE 425 Volker Boulevard, Kansas City, MO 64110-2299 (816) 753-7600
 Review of Proposed Revision to AP-42,
Section 8.6, Portland Cement

Final Report
by
Fred J. Bergman

For U.S. Environmental Protection Agency

Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711

Attn: Mr. Dennis R. Shipman

Contract No. 68-02-4395

Work Assignment No. 49
MRI Project No. 8987-49

September 30,1990

MIDWEST RESEARCH INSTITUTE 425 Volker Boulevard, Kansas City, MO 64110-2299 (816) 753-7600
 PREFACE

This report was prepared by Midwest Research. I n s t i t u t e (MRI) f o r the

Environmental Protection Agency's (EPA0s) O f f i c e o f A i r Q u a l i t y Planning and
Standards under EPA Contract No. 68-02-4395, Work Assignment No. 9.
M r . Dennis R. Shipman was the Project O f f i c e r f o r t h i s review. The work was
performed i n MRI's A i r Q u a l i t y Assessment Section. The author o f the r e p o r t
was Mr. Fred Bergman. Mr. John Kinsey provided technical support and review.

Approved f o r :

Engineering and Environmental

Technology Department

September 30. 1990

 SECTION 1

INTRODUCTION

The C r i t e r i a Emissions Section o f the Monitoring and Reports Branch (MRB)

has r e s p o n s i b i l i t y f o r developing and maintaining the document Compilation of
A i r Pollutant Emissions Factors. AP-42, which i s a basic source o f emission
f a c t o r s used i n preparation o f State Implementation Plans (SIPS), review o f
Prevention o f S i g n i f i c a n t Deterioration (PSD) applications, New Source Review
Permit Applications, and other Federal, State, and local assessments o f a i r
p o l l u t i o n sources.

This r e p o r t presents a review o f a proposed r e v i s i o n f o r Section 8.6 o f

AP-42. The proposed r e v i s i o n was prepared by a consultant o f the Portland
Cement Association. The review covered (1) evaluation o f the appropriateness
o f the emission data used, (3) evalua-
(2) evaluation o f the data treatment.
t i o n o f the background document. (4) review o f the emission factor r a t i n g , and
(5) a review o f the section text.
 SECTION 2

EMISSION DATA EVALUATION

2.1 REVIEW OF INDIVIDUAL DATA SETS

The r e p o r t on t e s t i n g a t t h e Cal MetICoulton P l a n t d i d n o t c o n t a i n

c a l i b r a t i o n data t o support t h e continuous emission monitors (CEMs) r e s u l t s .
The statement made t h a t t h e CEMs were granted c e r t i f i c a t i o n by t h e D i s t r i c t
Engineers was i n s u f f i c i e n t t o j u s t i f y an A r a t i n g f o r t h e r e p o r t . The r e s u l t s
were, therefore, lowered t o a B r a t i n g .

The Gilford-HillIRiverside plant report contained a number of

deficiencies. The coal a n a l y s i s was reported t o be done by t h e K j e l d a h l
Method. T h i s method c o n s i s t s o f t h r e e parts: digestion, d i s t i l l a t i o n ( t o
remove i n t e r f e r e n c e s ) , and measurement ( t i t r a t i o n ) . The t e s t i n g o r g a n i z a t i o n
performed t h e d i g e s t i o n and then used instrumental methods f o r analysis
without the d i s t i l l a t i o n . The r e p o r t s t a t e d t h e presence o f i n t e r f e r e n c e s
degraded t h e r e s u l t s . The r e s u l t s o f t h e n i t r o g e n a n a l y s i s i s questionable.

A l s o a t t h e G i l f o r d - H i l l / R i v e r s i d e p l a n t , t h e r e was no c e r t i f i c a t i o n s o f
t h e CEMs, t h e main f l o w c a l c u l a t i o n s were i n e r r o r , and t h e NO, method used
was nonstandard. An i n t e g r a t e d bag (Mylar) sample was c o l l e c t e d f o r l a t e r
analysis. (Note t h a t losses o f NO, i n Mylar have been documented and
published.) There were a l s o no h o l d i n g times provided on t h e bag samples and
no sample s t a b i l i t y (decay r a t e ) i n f o r m a t i o n provided.

Finally, the G i l f o r d - H i l l t e s t report i d e n t i f i e d cyclonic f l o w a t the

t e s t l o c a t i o n , and t h e t e s t o r g a n i z a t i o n e i t h e r took no c o r r e c t i o n a c t i o n o r
d i d n o t r e p o r t t h e a c t i o n taken. Moisture i n t h e stack was a l s o n o t measured
i n t h e same t i m e frame as t h e NO, sampling occurred. I n addition, t h e r e p o r t
s t a t e d i n "Discussion o f t h e Test Program' t h a t a l l data were c o l l e c t e d d u r i n g
upset conditions. Because o f t h e above f a c t o r s , t h e r a t i n g o f t h e t e s t was
lowered from A t o 0.

The Lafarge Corp./Alpena, Michigan and t h e Lehigh Plant/Waco, Texas

retained B ratings. We a l s o agreed w i t h t h e d e c i s i o n t o omit t h e Oklahoma
Cement/Pryor data.

The Southwest (SW)/Black Mountain, C a l i f o r n i a r e p o r t r e t a i n e d a B r a t i n g

f o r t h e October 9, 1980, t e s t . The o t h e r two t e s t s r e t a i n e d a B r a t i n g f o r
NO, measurements, b u t t h e SO, data were reduced t o a D r a t i n g . This r e d u c t i o n
was based. on observations t h a t t h e method employed f o r SO, probably measured
t o t a l sulfates.

The t e s t r e s u l t s from G i l f o r d H i l l / T X were reviewed. We agreed w i t h t h e

d e c i s i o n t o e l i m i n a t e t h e G i l f o r d H i l l / T X t e s t data.

Data from Lehigh/Camenton r e t a i n e d a B r a t i n g . However, Lonestar, Miami,

F l o r i d a was reduced from an A t o a B r a t i n g . T h i s r e d u c t i o n was made because
t h e r e p o r t consisted o f d a t a only.

The Lonestar/New Orleans t e s t s performed on November 11 and November 13,

1981, were given a C r a t i n g because they d i d n o t use standard procedures. The
t e s t s performed i n May o f 1982 and March o f 1984 were reduced from B t o C
ratings. T h i s r e d u c t i o n was made because t h e method employed f o r SO, was
nonstandard.

The Southwestern/Victorvi1le test performed on August 5, 1980, was

reduced from a B r a t i n g t o a C. T h i s r e d u c t i o n was made because t h e NO,
sample was c o l l e c t e d i n a Tedlar bag f o r l a t e r a n a l y s i s (nonstandard) and t h e
SO, was c o l l e c t e d i n a nonstandard and i n c o r r e c t t r a i n . The SW t e s t performed
on October 9, 1980, was reduced from a B t o a C f o r t h e same reason.

The Ashgrove/Durkee and the Calaveres/Bedding t e s t s r e t a i n e d t h e i r B

ratings.
 The Lehigh/Buda, Texas p l a n t r e p o r t was reduced from a B t o a C r a t i n g
because t h e r e p o r t contained no supporting data, and no even t h e methods used.

The Lonestar/Maryneal, Texas r e p o r t was n o t reviewed (could n o t be

located) and t h e SW/Fairborn t e s t remained r a t e d B.

The SW F l o r i d a Mining and t h e SW/Kosmosdale were reduced from a B t o a C

rating. The r e d u c t i o n waF made because t h e r e p o r t s contained o n l y d a t a w i t h
no supporting information.

The SW/Odessa values f o r NO, remained r a t e d A b u t t h e SO, data were

reduced t o a C r a t i n g . The r e d u c t i o n was made because t h e SO, t r a i n varied
from t h e EPA method making t h e r e s u l t s questionable.

The Cal Mat/Majave t e s t remained 8, as d i d t h e Lonestar/Davenport data.

The SO, data from t h e Marquqtte/Cape Girardeau and Lonestar/Cap Girardeau

1,
both remained r a t e d B. I .

SW/Leamington remained an A but t h e S W / V i c t o r v i l l e t e s t s conducted i n

1985 and 1987 were reduced from an A t o a 0. The r e d u c t i o n was made because
t h e CEMs were n o t c e r t i f i e d a t t h i s source. The t e s t o r g a n i z a t i o n c a l c u l a t e d
an F f a c t o r using CEM data which i s s p e c i f i c a l l y forbidden (only Orsat i s
acceptable). I n addition, t h e probe washings were evaporated on a h o t
plate.
- &mv4OK
Also i n the =stated t h e CO
analyzer was ~ 0 , - c o r r h dd i d n o t c o r r e c t f o r t h e water i n t e r f e r e n c e .
The CO d a t a should be obtained on a d r y gas stream not one provided by a
p r e c o n d i t i o n e r operating a t 70°F. I n a d d i t i o n , i f the c o r r e c t i o n made on t h e
CO d a t a by c a l c u l a t i o n were acceptable, how does t h e t e s t o r g a n i z a t i o n e x p l a i n
d r i f t s o f 275 ppm and e r r o r s o f 100% when t h e system was spanned a t 200 ppm?
A f i n a l problem was t h e r e p o r t ' s conclusion t h a t the NO, values were v a l i d
because they were checked using EPA Method 20, when Method 7 should have been
used. The same problems were observed i n a l l o f t h e t e s t s performed d u r i n g
t h i s ' r e p o r t e d t e s t period.
2.2 REVIEW OF THE DATA TREATMENT REPORT

The main t h r u s t o f t h e Data Treatment Report was t h e use o f a s t a t i s t i c a l

e v a l u a t i o n o f t h e data. T h i s approach was employed p a r t i a l l y t o overcome t h e
v a r i a b i l i t y o f t h e data. However, i t was our f i n d i n g t h a t much o f t h e v a r i -
a b i l i t y was e l i m i n a t e d d u r i n g t h e above d a t a reassessment. The NOx d a t a o f A
and B r a t i n g s v a r i e d from 2.31 t o 6.70 lb/ton. This compares t o t h e previous
values o f 1.68 t o 17.5 lb/ton. I n t h e case of 50,. the n e w e v a l u a t i o n ranged - --

from 0.32 t o 7.25 l b / t o n where t h e previous values were 0.03 t o 18 l b / t o n . As

can be seen, t h e d a t a v a r i a b i l i t y was diminished by the new r a t i n g s discussed
i n Section 2.2.

2.3 REVIEW OF THE BACKGROUND DOCUMENT

There seems t o be a problem w i t h i n t h e treatment o f s u l f u r o x i d e i n t h e

Background Document. It was our understanding t h a t t h e emission f a c t o r was t o
be developed f o r s u l f u r d i o x i d e (SO,) n o t SO.,
However, most references i n
t h e Background Document and t h e Proposed Section Revision uses t h e summary
term s u l f u r oxides (SO,). T h i s term includes s u l f u r dioxide, s u l f u r t r i o x i d e ,
and s u l f a t e s . I n f a c t , o n l y Section 1.4.2 i n t h e Background Document uses t h e
term 50,. I n a d d i t i o n . Reference 3 o f t h e Background Document uses t h e term
SOx b u t t h e t e s t r e f e r s t o these data as SO,. References 7, 11, 22. and 23
r e f e r t o SO, i n t h e i r t i t l e s and references 14, 17, 27, 29, and 3 1 r e f e r t o
SO2. I n r e a l i t y , t h e term used i n various t i t l e s seldom represents t h e form
measured d u r i n g t h e t e s t s .

EPA Method 6 and CEMs are t h e c o r r e c t way t o measure SO,. Method 8

measures SO, p l u s s u l f u r i c a c i d m i s t s ( t h e form o f SO, found i n a gas stream
c o n t a i n i n g moisture). To o b t a i n t o t a l SOx would r e q u i r e t h e use o f a Method 8
t r a i n p l u s a s u l f a t e determination on t h e p a r t i c u l a t e catch. I n addition, t h e
determination o f so-called SO, using a CEM, as i s reported i n many o f t h e
documents, i s n o t p o s s i b l e since the c o n d i t i o n i n g system used would remove any
So3.

The reference documents and the background were, therefore, reviewed w i t h

these f a c t s i n mind. Much o f t h e s u l f u r oxide data was lowered t o e i t h e r a C
o r a D r a t i n g because i t d i d n o t represent SO, concentrations. I t i s , there-
fore, recommended t h a t a l l references t o SOx i n both t h e Background Document
and t h e proposed Section 8.5 o f AP-42 be changed t o SO,.

We a r e i n agreement t o t h e exclusions o f data from Oklahoma Cement/Pryor

and G i l f o r d - H i l l s No. 3 k i l n described i n the Background Document Sec-
t i o n 1.4.2. I n a d d i t i o n we excluded d a t a from G i l f o r d - H i l l Riverside, t h e SO,
data from SW Back Mountain, and t h e SW V i c t o r v i l l e k i l n No: 2 data. Explana-
t i o n f o r these exclusions were provided i n Section 2.1.

The proposed values i n Section 1.5 o f t h e Background Document should be

changed t o r e f l e c t t h e change i n d a t a r e s u l t i n g from t h i s review.

Table 1 c o n t a i n s a l l A and B r a t e d emission f a c t o r s d e r i v e d from t h e

experimental data.

TABLE 1. A AND B EMISSION FACTORS FOR PORTLAND CEMENT KILNS

Reference Ref ere;ce

K i l n type SO, l b / t o n NQ.~ NOx 1b/tons No.

Dry process

- - 5.17
- ~ - ~

8
-
- - -
5.16 9
Average 7.0 Average 5.7
Wet process 4.51 20 5.23 15
Preheater - - 5.78 32
- - -
5.64 33
- - Average 5.5
Precalciner 0.77 36 2.81 36
1.00 36 3.43 36
1.45.. 4.49 36
... 0.32 $3 8.62 39
-
1.25 38 -
Average 11.0, Average 4.8
\
'- - <*I
a see Table 1 o f Appendix f o r referen& nu
I ,
 Because o f t h e s c a r c i t y o f data r a t e d A and 8, C r a t e d d a t a were used t o
develop emission f a c t o r s f o r SO, and NO, f o r wet process k i l n s and a SO,
f a c t o r f o r preheaters. The i n d i v i d u a l C r a t e d values and t h e i r averages a r e
presented i n Table 2.

TABLE 2. C RATED EMISSION FACTORS FOR WET PROCESS CEMENT KILNS

AND PREHEATER KILNS

Reference Reference
K i l n type SO, l b / t o n NO.^ NO, lb/tons NO.^

Wet process 2.76

18.08
4.54
0.40
1.93
4.70
1.76
6.12
5.32
14.20
0.39
0.48
0.99
8.02
2.71
3.60
8.80
15.90
5.40
13.70 -
-
Average 6.0 Average 8.2

Preheaters 0.85 25
1.59 26
2.04 29
0.07 31
0.09 32
-
0.01 82
Average 0.8
-- - -

a see Table 1 o f Appendix f o r reference numbering.

 Based on the above data we propose t h a t the emission f a c t o r s g i v e n i n
Table 3 be used i n place o f those provided i n the document reviewed.

TABLE 3. PROPOSED EMISSION FACTORS

SO, l b / t o n NO l b / t o n
K i 1n type (kg/Mg) Rating (fig/~g) Rating

Dry process 7.0 (2.9) B 5.7 (2.4) B

Wet process 6.9 (2.5) C 8.2 (3.4) C
Preheater 0.8 (0.3) C 5.5 (2.3) B
Precalciner 1.0 (0.4) 8 4.8 (1.7) B
 SECTION 3

AP-42 SECTION

The t e x t o f t h e proposed AP-42 s e c t i o n has been reviewed and r e v i s e d t o

t h a t shown i n t h e f o l l o w i n g pages. A number o f e d i t o r i a l changes have been
included. The f i g u r e numbers have a l s o been changed t o match t h e t e x t and t h e
discussion o f a l t e r n a t e f u e l s was changed t o e l i m i n a t e t h e imp1 i c a t i o n t h a t
k i l n s are operated on 100% a l t e r n a t e f u e l s . To our knowledge k i l n s are n o t
been operated on 100% waste.

Table 1, Emission Factors f o r Cement Manufacturing f o r P a r t i c u l a t e , NOx,

and SOx (Appendix), does n o t provide u n i t s f o r t h e proposed numbers. Compari-
sons w i t h t h e u n i t s i n Table I 1 1 o f t h e Methodology Development Document
implies t h a t the u n i t o f l b / t o n i s correct. The term SO, i n t h e t a b l e heading
should a l s o be changed t o 50,.

The values f o r p a r t i c u l a t e s given i n Table I 1 1 do n o t agree w i t h t h e

values c u r r e n t l y contained i n Table 8.6-1 o f AP-42. There was no d i s c u s s i o n
I n t h e documents reviewed t o e x p l a i n t h e d i f f e r e n t numbers. It i s , therefore,
proposed t h a t t h e p a r t i c u l a t e l e v e l s provided i n t h e e x i s t i n g Table 8.6-1 be
r e t a i n e d w i t h t h e NO, and SO, values changed t o r e f l e c t t h e new data.
8.6 PORTLAND CEMENT MANUFACTURING

8.6.1 Process Description

Most of t h e h y d r a u l i c cement i n t h e United S t a t e s i s p o r t l a n d cement.

P o r t l a n d cement, a c e m e n t i t i o u s , c r y s t a l l i n e compound composed o f m e t a l l i c
o x i d e s , i s produced by a p y r o p r o c e s s i n a r o t a r y k i l n from raw m a t e r i a l s ,
e.g., l i m e s t o n e , s h a l e , c l a y and sand, c o n t a i n i n g c a l c i u m c a r b o n a t e and
aluminum, i r o n , and s i l i c o n o x i d e s . The s t e p s o f t h i s p r o c e s s a r e shown i n
F i g u r e 1. T h i s m a n u f a c t u r i n g p r o c e s s may be c o n v e n i e n t l y d i v i d e d i n t o f i v e
s t a g e s c o r r e l a t e d w i t h l o c a t i o n and t e m p e r a t u r e of t h e m a t e r i a l s i n t h e r o t a r y
kiln:

1. E v a p o r a t i o n of uncombined w a t e r from raw m a t e r i a l s o c c u r s a s

m a t e r i a l t e m p e r a t u r e i n c r e a s e s t o 212-F.
, 2. A s t h e m a t e r i a l t e m p e r a t u r e i n c r e a s e s from 212-F t o a p p r o x i m a t e l y
800aF, d e h y d r a t i o n and p r e c a l c i n a t i o n o c c u r .
3. Between 800° and 1650°F, c a l c i n a t i o n o c c u r s i n which c a r b o n d i o x i d e
i s l i b e r a t e d from t h e c a r b o n a t e s .
4. Following c a l c i n a t i o n , s i n t e r i n g o f t h e o x i d e s o c c u r s a t tempera-
t u r e s up t o 2750°F i n t h e b u r n i n g zone of t h e r o t a r y k i l n .
5. Following s i n t e r i n g , cement c l i n k e r i s produced a s t h e t e m p e r a t u r e
of t h e m a t e r i a l d e c r e a s e s from 2750" t o 2500°F.

The raw m a t e r i a l mix e n t e r s t h e k i l n a t t h e e l e v a t e d end ( F i g u r e 8.6-11,

and t h e b u r n e r i s a t t h e o p p o s i t e end. The raw m a t e r i a l s a r e t h e n changed
i n t o c e m e n t i t i o u s o x i d e s o f m e t a l s by a c o u n t e r c u r r e n t , heat-exchange pro-
c e s s . The m a t e r i a l s a r e c o n t i n u o u s l y and s l o w l y moved t o t h e lower end by t h e
r o t a r y movement o f t h e k i l n . The f u e l burned i n t h e k i l n i s n a t u r a l g a s , o i l ,
o r c o a l . S i n c e 1974, many cement p l a n t s have c o n v e r t e d t o c o a l b u t r e c e n t l y
supplemental f u e l s such a s waste s o l v e n t s , chipped rubber, shredded municipal
g a r b a g e , and coke have been used.

T h e r e a r e t h r e e v a r i a t i o n s i n t h e cement m a n u f a c t u r i n g p r o c e s s , i.e.,
w e t , d r y , and d r y p r e h e a t e r / p r e c a l c i n e r p r o c e s s e s . These p r o c e s s e s a r e essen-
t i a l l y i d e n t i c a l r e l a t i v e t o t h e manufacture o f cement from raw m a t e r i a l s .
However, t h e t y p e of p r o c e s s d o e s change t h e equipment d e s i g n , t h e method of
o p e r a t i o n , and t h e consumption o f f u e l . F u e l combustion i s d i f f e r e n t between
w e t and d r y p r o c e s s e s and t h e p r e h e a t e r l p r e c a l c i n e r p r o c e s s . In t h e former,
a l l f u e l combustion o c c u r s i n t h e k i l n . I n t h e l a t t e r , some f u e l combustion
occurs i n a precalcining o r c a l c i n i n g v e s s e l before the m a t e r i a l s e n t e r t h e
k i l n ( F i g u r e 8.6-2). G e n e r a l l y s p e a k i n g , t h e l e n g t h o f t h e r o t a r y k i l n and
t h e consumption of f u e l d e c r e a s e a s t h e m a n u f a c t u r i n g p r o c e s s changes from wet
t o d r y t o p r e h e a t e r l p r e c a l c i n e r equipment f o r t h e same mix d e s i g n o f raw mate-
r i a l s . However, t h e r e l a t i o n s h i p i s n o t l i n e a r . The B t u l t o n s i g n i f i c a n t l y
d e c r e a s e s a s p l a n t c o n f i g u r a t i o n changes from wet t o d r y t o e r e h e a t e r /
precalciner.

Mineral P r o d u c t s I n d u s t r y
 Figures 8.6-1. Conventional kiln.

Figure 8 . 6 - 2 . Preheaterlprecalciner.

M I S S I O N FACTORS
8.6.2 Emissions and Controls

P a r t i c u l a t e m a t t e r , NO, and S O 2 , CO and C02, are t h e primary emissions i n

t h e manufacture o f portland cement. But, emissions may a l s o include minute
m a t e r i a l s form t h e f u e l and raw m a t e r i a l s .

Sources o f dust a t cement plants include ( 1 ) quarrying and c r u s h i n g ,

( 2 ) raw material s t o r a g e , ( 3 ) grinding and blending ( d r y process o n l y ) ,
(4) c l i n k e r production, ( 5 ) f i n i s h grinding, and ' ( 6 ) packaging ( s e e F i g -
ure 8.6-3). The l a r g e s t source o f emissions w i t h i n cement plants i s t h e k i l n
operation, which has t h r e e u n i t s : t h e feed system, t h e f u e l - f i r i n g system,
and t h e clinker-cooling and handling system. The most d e s i r a b l e method o f
disposing o f t h e c o l l e c t e d dust i s i n j e c t i o n i n t o t h e burning zone o f t h e k i l n
and production o f c l i n k e r s from t h e d u s t . I f t h e a l k a l i content o f t h e raw
m a t e r i a l s i s too h i g h , however, some o f t h e dust i s discarded or leached
b e f o r e returning t o t h e k i l n . In many i n s t a n c e s , t h e maximum allowable cement
a l k a l i content o f 0.6 percent ( c a l c u l a t e d as sodium o x i d e ) r e s t r i c t s t h e
amount o f dust t h a t can be recycled. Additional sources o f dust emissions are
raw material storage p i l e s , conveyors, storage s i l o s , and loading/unloading
facilities.

The complications o f k i l n burning and t h e large volumes o f m a t e r i a l s

handled have led t o t h e adoption o f m n y control systems f o r dust c o l l e c t i o n .
Depending upon t h e emission, t h e temperature o f t h e e f f l u e n t s i n t h e plant i n
q u e s t i o n , and t h e p a r t i c u l a t e emission standards i n the c o w u n i t y , t h e cement
i n d u s t r y generally uses mechanical c o l l e c t o r s , e l e c t r i c a l p r e c i p i t a t o r s ,
f a b r i c f i l t e r (baghouse) c o l l e c t o r s , or combinations o f t h e s e devices t o
control emissions.

Oxides o f nitrogen ( N O x ) are generated during the f u e l combustion by

o x i d a t i o n o f chemically bound nitrogen i n t h e f u e l and by thermal f i x a t i o n o f
n i t r o g e n i n t h e combustion a i r . As the flame temperature i n c r e a s e s , t h e
amount o f thermally generated NOY i n c r e a s e s , and t h e amount o f NOx generated
from f u e l increases as t h e q u a n t i t y o f n i t r o g e n i n the f u e l increases. In t h e
cement manufacturing process, t h e r e are two combustion zones i n which NO, may
be generated, i.e., t h e burning zone o f t h e k i l n and t h e burning zone o f a
precalcining v e s s e l (Figure 1 ) . Also, t h e t y p e o f f u e l burned w i l l a f f e c t t h e
q u a n t i t y and t y p e o f NO generated. Natural gas combustion w i t h a high flame
temperature and low f u e f nitrogen may generate a d i f f e r e n t q u a n t i t y o f NOx
than o i l or c o a l , which have higher f u e l nitrogen but lower flame
temperatures.

The f u e l s vary i n t h e cement manufacturing process. Generally, natural

gas i s used only i n t h e k i l n , while coal and o i l are used i n t h e k i l n and
precalcining v e s s e l . T h e r e f o r e , t h e generation and emission o f NOx are
r e l a t e d t o t h e t y p e o f f u e l burned and t o t h e e x t e n t t h a t f u e l a f f e c t s t h e
flame temperature and contains chemically bound nitrogen.

P r e s e n t l y , t h e r e are data t o support only two t y p e s o f reduction o f NO,

i n t h e cement i n d u s t r y . F i r s t , f o r conventional wet and dry-process k i l n s ,
NO, emissions are reduced by f u e l conversion w i t h coal producing t h e l e a s t
amount o f NO,. With new c o n s t r u c t i o n , t h e data are not yet c l e a r . Some
p r e h e a t e r / p r e c a l c i n e r systems have low emissions; others have high emissions.

Mineral Products Industry 8.6-3

 \
----. 2
TO

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rlru...c*n.
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CIWHll S I A C I L I - I I C U I Y I N O S117.1.
7- k..Inr k. I V O U C I A N D ilrND1HC

1. Quarrying and blending of raw materials. \,

\ "07 c...~ ;O
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f

0". MIIYla U I D CIO",., "A*

*LC*OI*C YLO. Y*TE"I.L ,TO".CI.

2. Proportioning and fine grinding of raw materials.

J
f 3
FOUR.STAGS
SUS.C*SIO* "L"U.L"
10, w.
a". .10.1....",
t a n ,I"

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4
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Ur".,,." -8- I
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.
i*! DUST 1OrAT11G KILN NMran
.I* COOLl" SLI*"."
,7O".CK
3. Kiln system. Preheating, burning, cooling and clinker storage.
J
f .fm CSYLYI 3

rooeo L! D"I*OIYC ",LL

DUL* S T O I I U lUL" lULI .OX ,.Cx.CI*a ,"UCI
TlUC" 011 C** ".,C*,"'

4. Finish grinding and shipping.

J
Figure 8.6-3. S t e p s i n t h e manufacture o f portland cement by dry p r o c e s s
u s i n g preheater.

8.6-4 MISSION FACTORS

 There i s not a s i n g l e type o f preheaterlprecalciner system used i n t h e
cement i n d u s t r y , instead t h e r e are a t l e a s t t e n d i f f e r e n t systems. Each sys-
tem appears t o have unique emissions properties. However, i t does appear t h a t
f o r a s i n g l e system, o i l i n the c a l c i n e r produces l e s s NO, than coal. The No,
emissions from t h e preheateriprecalciner appear t o be r e l a t e d t o t h e i r design.
Some have very low emissions and o t h e r s have emissions i n a mid-range o f some
conventional or wet processes. At t h e present t i m e , t h e r e are i n s u f f i c i e n t
data t o choose a N S P system t o minimize NO, emissions.

S u l f u r dioxide may be generated from t h e s u l f u r compounds i n t h e raw

m a t e r i a l s , as well as from combustion o f f u e l . The s u l f u r content o f both raw
m a t e r i a l s and f u e l s w i l l vary from plant t o plant and w i t h geographic loca-
t i o n . The a l k a l i n e nature o f t h e cement, however, provides f o r d i r e c t absorp-
t i o n o f SO2 i n t o t h e product. I f a baghouse t h a t allows t h e S O 2 t o come i n
contact w i t h t h e cement dust i s used, t h e overall control inherent i n t h e
process i s approximately 7 5 percent or greater o f t h e a v a i l a b l e s u l f u r i n raw
m a t e r i a l s and f u e l . Control, o f course, w i l l vary according t o t h e a l k a l i and
s u l f u r content o f t h e raw materials and f u e l .

The CO emissions are associated w i t h t h e e f f i c i e n c y o f t h e combustion

process, and t h e C02 i s generally a r e l e a s e o f 33 percent o f t h e weight o f t h e
limestone i n t h e calcining process. C u r r e n t l y , there are no methods a v a i l a b l e
f o r reducing CO or C02 except process control f o r CO and reduction o f
production f o r C02.

8.6.3 Emissions Factors

Table 8.6-1 through 8.6-4 g i v e emission f a c t o r s f o r cement manufacturing,

including f a c t o r s based on p a r t i c l e s i z e . S i z e d i s t r i b u t i o n s f o r p a r t i c u l a t e
emissions from controlled and uncontrolled k i l n s and c l i n k e r coolers are a l s o
shown i n Figures 8.6-4 and 8.6-5.

Mineral Products Industry

 TABLE 8.6-1. UNCONTROLLED EMISSION FACTORS FOR CEMENT HANUFACTURING~--COAL COMBUSTION
Emission Factor Rating: E

b
Particulate Sulfur dioxide Nitrogen oxide Lead
Process kglMg lb/ton kg/@ lb/ton kg& lblton kg& lblton

Dry process kiln 128 256 3.Sc 2.9' 5.7C 0.06 0.12
dryer d 48 96 - -7.0' - - 0.02 0.04

g Wet process kiln 120 240 3.0~ 6.0e 4.1e

H
rn
dryer d 16 32 - - - -8.2e 0.05
0.01
0.10
0.02
V)
H
o
2
Clunker cooler f 4.6 9.2 - - - - - -
9
g Prehester kiln - - 0.4~ 0.8~ 2.8' 5.Sc - -
8
a Precalciner kiln - - 0.5' l.OC 2.4' 4.8' - -
Y)

'~eferences 1-2. Expressed in terms of units of clinker produced, assuming 5% gypsum in finished
cement. Includes fuel combustion emissions, which should not be calculated separately. Dash indi-
cates no data.
bEmission Factor Rating: B
'Emission Factor Rating: B per Reference 13.
* ~ x ~ r e s s e in
d terms of units of cement produced.
e ~ m i s s i o nFactor Rating: C per Reference 13.
f~eference8. Emission Factor Rating: D.
 TABLE 8.6-2. CONTROLLED PARTICULATE EMISSION FACTORS FOR
CEMENT MANUFACTURINGa

Type Control Particulate Emission

0f technology kg 1Mg lblton Factor
source clinker clinker Rating

Wet process k i l n Baghous e 0.57 1.1 C

ESP 0.39 0.78 C

Dry process k i l n . Multiclone 130b 260b D

Multicyclone
+ ESP 0.34 0.68 C
Baghouse 0.16 0.32 B

Clinker c o o l e r Gravel bed

filter 0.16 0.32 C
ESP 0.048 0.096 D
Baghous e 0.010 0.020 C

Primary l i m e s t o n e
crusherC Baghouse 0.00051 0.0010 D

Primary l i m e s t o n e
screenC Baghouse 0.00011 0.00022 D

Secondary l i m e s t o n e
s c r e e n and c r u s h e r C Baghouse 0.00016 0.00032 D

Conveyor t r a n s f e r c Baghous e 0.000020 0.000040 D

Raw m i l l stern^^^ Baghouse 0.034 0.068 D

F i n i s h m i l l systeme Baghouse 0.017 0.034 C

aReference 8. Expressed a s kg particulate1Mg ( l b p a r t i c u l a t e l t o n ) of c l i n k e r

produced, except a s noted. ESP = e l e c t r o s t a t i c p r e c i p i t a t o r .
b ~ a s e don a s i n g l e t e s t of a dry process k i l n f i r e d with a combination of
coke and n a t u r a l g a s . Not g e n e r a l l y a p p l i c a b l e t o a broad c r o s s s e c t i o n
of t h e cement i n d u s t r y .
CExpressed a s mass of p o l l u t a n t / m a s s of raw m a t e r i a l processed.
d ~ n c l u d e sm i l l , a i r s e p a r a t o r and weigh f e e d e r .
eIncludes m i l l , a i r s e p a r a t o r ( s ) and one o r more m a t e r i a l t r a n s f e r o p e r a t i o n s .
Expressed i n terms of u n i t s of cement produced.

Mineral Products I n d u s t r y
 TABLE 8.6-3. SIZE SPECIFIC PARTICULATE EMISSION FACTORS FOR CEMENT K I L N S ~

EMISSION FACTOR RATING: D

Partlele Cuul.tIve oa.8 1 < s t a r e d .l=rb Curul.tlve n.la.lan f a c t o r ( .t.ced alzcc

a1.e
( ) uncontrolled U ~ Y wet Ba8hou.r Uneorlrrollrd ~ r proeeas
y u c r procesa naghouse
uet Dry pcocee. procc.. wet Dry Yet O ~ Y wlih ulrh wet DCY
Pr0~c.e procea. klln rlrh klln rlrh p r o c e m prueema Procea. Precess mulllcloned ESP
klln kiln m u l t ~ e ~ o n c ~ ESP LII~ kiln 4 / ~ gl b l r a n &/ng ~blton kg/% IblronkglHg Ib/ron

101.1 mame mnlmalon f a c t o r 120e 7.40' 120' 256- llof 260f 0.3sf 0.781 0.57~ l.lf 0.16~ 0.31f

all.t.rance
b4.rc-d~-lc
8. ESP -
dluorer.
electro.tatlc preelplcaror. - W nor .u.ll.bls.
Percentage. rounded t o two e l g o l f l c a n l flgures.
-
Da.h no data.

Cbpr*..ed a. v n l l r e l g h r o f p.rtlcul.te/unir r s l g h l o f clinker produced. aawmlng 5 1

'ypaur I n f l n l a h e d c-cnt. Pounded t o t w o . I g n l f l c a n t figure..
db..ed on a .Ingle t e a t . and should b e used w i t h caurlon.
* I r a T a b l o 0.6-1.
l?r- r a b l e 8.6-2.
 TABLE 8 . 6 - 4 . SIZE SPECIFIC EMISSION FACTORS FOR
CLINKER COOLERSa

EMISSION FACTOR RATING: E

I particle Cumulative mass Z Cumulative emission f a c t o r

sizeb < stated sizec < stated sized
Uncontrolled Gravel bed f i l t e r Uncontrolled Gravel bed f i l t e r

I
J
Tocal mass emission f a c t o r

aReference 8 .
b ~ e r o d y n a m i cd i a m e t e r
CRounded t o two s i g n i f i c a n c f i g u r e s .
weight of p o l l u t a n t l u n i t weight of c l i n k e r
produced. Rounded t o two s i g n i f i c a n t f i g u r e s .
eProm Tab1 e 8.6- 1.
prom Table 8 . 6 - 2 .

Mineral Products I n d u s t r y
 -- I 1 I I 1 1 1 1 I I I I l l
--
114
-- -

-
---
-- ---
- -
- -
- @ -
---
--

Wet Process Kiln with ESP

Dry Process Kiln with Boghouse

0.1 0.01
1 .o 10 100
Aerodynamic Particle Diometer ( p m A )

Figure 8 . 6 - 4 . S i z e s p e c i f i c emission f a c t o r s f o r cement k i l n s .

MISSION FACTORS
 I

Uncontrolled Coolers
Coolers with Gravel Bed Filter

Aerodynamic Particle Diameter ( p m A )

Figure 8.6-5. S i z e s p e c i f i c emission factors for clinker c o o l e r s .

Mineral Products Industry

 REFERENCES

1. K r e i c h e l t , T.E., et a l . , Atmospheric Emissions from t h e Manufacture o f

P o r t l a n d Cement, 999-AP-17, U.S. Environmental P r o t e c t i o n Agency,
C i n c i n n a t i , OH, 1967.

2. Background I n f o r m a t i o n f o r Proposed New Source Performance S t a n d a r d s :

P o r t l a n d Cement P l a n t s , APTD-0711, U.S. Environmental P r o t e c t i o n Agency,
R e s e a r c h T r i a n g l e P a r k , NC. August 1971.

3. A S t u d y o f t h e Cement I n d u s t r y i n t h e S t a t e o f M i s s o u r i . Resources
R e s e a r c h I n c . , Reston, VA, December 1967.

5. S t a n d a r d s o f Performance f o r New S t a t i o n a r y Sources. 36 FR 28476,

December 1971.

6. P a r t i c u l a t e P o l l u t a n t System Study. EPA C o n t r a c t No. CPA-22-69-104,

Midwest R e s e a r c h I n s t i t u t e , Kansas C i t y , MO, May 1971.

7. R e s t r i c t i o n o f Emissions from P o r t l a n d Cement Works. VDI Richtlinien.

D u s s e l d o r f , West Germany, F e b r u a r y 1967.

8. Kinsey, J.S., Lime and Cement I n d u s t r y -

Source C a t e g o r y R e p o r t , Vol. 11,
EPA C o n t r a c t No. 68-02-3891, Midwest Research I n s t i t u t e , Kansas C i t y , MO,
August 1 4 , 1986.

9. May, M.S., NO, G e n e r a t i o n , Emission and C o n t r o l from Cement K i l n s i n t h e

U n i t e d S t a t e s . I n : P r o c e e d i n g s of t h e 1982 J o i n t Symposium on
S t a t i o n a r y Combustion NO, C o n t r o l . P r e p a r e d by E l e c t r i c Power R e s e a r c h
I n s t i t u t e , P a l o A l t o , CA.

10. May, M.S., J . M . Croom, R. MacMann, J.C. P h i l l i p s , and G.L. Young,

N i t r o g e n Oxide Emissions from Cement K i l n Exhaust Gases by P r o c e s s
M o d i f i c a t i o n . In: P r o c e e d i n g s o f t h e 1987 J o i n t Symposium on S t a t i o n a r y
Combustion NO, C o n t r o l . Prepared by E l e c t r i c Power R e s e a r c h I n s t i t u t e ,
P a l o A1to;CA.

11. Croom, J., M. May, G. Young, C. P h i l l i p s , and R. MacMann, NO, F o r m u l a t i o n

i n a Cement K i l n : Regression A n a l y s i s . In: P r o c e e d i n g s o f t h e 1987
-
J o i n t Symposium on S t a t i o n a r y Combustion NO, C o n t r o l . P r e p a r e d by
~ l e c t r i cPower Research ~ n s t i t u t e ,P a l o ~ l t g ,CA.

12. Methodology f o r Development o f SO,/NO, Emission F a c t o r , PSM

I n t e r n a t i o n a l , I n c . , D a l l a s , TX, J u l y 26, 1990.

8.6-12 EMISSION FACTORS

13. Bergman, F . , Review o f Proposed R e v i s i o n t o AP-42 S e c t i o n 8 . 6 , Portland
Cement Manufacturing, EPA Contract No. 68-02-4395, Midwest Research
I n s t i t u t e , Kansas C i t y , M0, September 30, 1990.

Mineral Products Industry

 APPENDIX

METHODOLOGY FOR DEVELOPMENT OF SO,/NO, EMISSION FACTORS

PREPARED- BY PSM INTERNATIONAL, INC.
METHODOLOGY FOR DEVELOPMENT
OF SOJNO, EMISSION FACTORS

by
PSM International, Inc.
703 McKinney Ave. Suite 430-436
Dallas,TX 75202

26 July 1990
This study and report have been preparedon the behalfof, and
for the exclusive use ofthe Environmental Protection Agency
and the Portland Cementhsxiation. Thin report and its h d s
may be used for the purpose for which it w i prepared: The
revision of the Emission Faaora for Air Pollutant Emissions
fmm themrtland Cement M a n u f a c t u ~ n k s n This
. mmrt
andim tidings shall not in wholeorparc;beused by any p&y
in wholear in part,forany otherpurpose, without priorwritten
consent O~PSM.No wananty, expressed or implied. is made.
-PSM Int&national, Znc. Draft Subject to Change

METHODOLOGY FOR DEVELOPMENT

1
OF SOx/NOxEMISSION FACTORS
1.0 INTRODUCTION
This report provides the methodology for development of the emission factors for SO, and NO, a s
urovidedinrevisionsofAP42 Section8.6by PSMInternational, Inc. Thisincludesrationaleforcement
kiln subdivision, criteria for rating and selecting data, and emission factor estimation. Emissions
I
were standardized to pounds (and kilograms) of emission species per ton (and metric tons) of clinker
produced l b f l or (kgshfl').
1.I EMISSION FACTORS ESTIMATION
1.1.1 DISTRIBUTIONAL ANOMALIES OF EMISSION FAmORS
Distributional anomalies of SO, and NO, data made estimation of emission factors difficult and
uncertain. Figure 1 shows the distribution in class intervals of all facility data for SO=andNO, data.
NO, (18 estimates from 25 facilities) exhibits an even distribution with five observations each in
intervals 2 - 4 , 4 - 6, and 6 - 8 lbfl and three observations greater than 8 l b f l . No transformation
appliesto an even distribution to normalize its variation; the arithmeticmean or average adequately
estimates its central tendency. All of the data reviewed is shown in Table I.
The distribution of SO, emissions for the facilities (22 estimates from 25 facilities) did not fit any
reasonable distribution. While i t resembles a Poisson or hypergeometric distribution, i t fits neither
of these well; therefore, no transformation couldbe applied to normalize S0,dataeither. Plotsofdata
for each facility by process type failed to reveal any more information regarding distribution (Figures
2.3.4, and 5).
1.12 ESTIMATION OF EMISSION FACTORS
Application of normal statistics to either of the data distributions discussed above would result in
an overestimation of the variance (dispersion aboutthe distribution's central tendency). Consequently,
application of the standard approach to calculation of the upper 95% coFdence limit (one-tailed)
would have resulted in an emission factor higher than it should be. However, premise of the 95%
confidencelimitwas accepted asabasisfor developmentofan alternativeapproach toemission factor
estimation.
By definition, the 95% confidence limit identifies 5% of legitimate observations a s lying outside the
acceptable range about the mean. In the case of the SO, and NO, data in Table I (the same data as
are plotted in Figures 2,3,4, and 51, application of the above premise would result in approximately
one each observation of SOxand NO, being identified as higher than its emission factor. By trial and
error, i t was determined that the arithmetic mean plus one standard deviation was a good first
approximation to application of the 95% confidence interval premise. ForNO,, one of eighteen facility
estimates was identified as higher than its process emission factor (Table 11). For NO, , t h e mean
plus one standard deviation estimate worked satisfactorily.
For S O , the mean plus one standard deviation did not work as well; three of twenty-two facility
estimates were identified as higher than their respective process emission factors (Table I). Rom
Table I, one estimate from wet process clearly exceeds its emission factor while one each estimate
for preheater and precalciners exceed each of their relatively low emission fadors (1.5 and 1.6 lbsl
T,respectively). For these two processes with theirrelatively low SO,emissions, theUmeanplusonen
approach is too restrictive. Adding a second standard deviation to the meansfor these two processes
results in emission factors which do not exclude any of the facility estimates for preheaten and
precalciners. Therefore for SO,, applying the approach of the "mean plus one" to dry and wet
processes and the "mean plus two" to preheater and precalciner processes, results in emission factors
identify only one facility estimateabove the proposed emission factor. While cumbersome, the
application of these two criteria for estimating SOx emission factors meets the premise of the 95%
confidence limit satisfactorily.

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1 2 3 4 5
Number of Obsewations
Figure 1: Distribution of all observations of SOzand NO=

p-
1 NOx

2 3 4
Number of Facilities

Figure 2: Dry process emissions of SO*and NO*

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1'1 NOx

1 I 5

Number of Facilities

Figure 3: Wet process emissions of SO=and NO=

3 4 5 6

Number of Facilities

Figure 4: Preheater emissww of SOzand NO*

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2 3 4

Number of Facilities

Figure 5: Precakiner emissions for SO=and NOz

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TABLE 11
Draft Subject t o Change

1
SO, AND NO, EMISSION FACTOR CALCULATION
Process SOxlbm NO, Ibs/T Emission Factors lbsf'
sox NOx
Dry Process 6.65
0.18 7.8 Both "mean plus one"
6.72 4.25
7.25 6.16
0.4 5.89 7.5 7.4
Mean 3.64 6.15
St Dev 2.132 2.015
CV 106 % 21 %

Wet Process 2.76

4.51
18.08
2.29 Both 'mean plus one"
6.32
2.52
9.48 12.3 11.2
Mean 6.57 7.71
St Dev 5.693 3.494
CV 87 % 45 %

Preheater
0.85 SO="mean plus two"
1.59 NO, "mean plus onen
0.03
2.04
0.07
0.09
0.01
Mean 0.67
St Dev 0.846
CV 127 %

Precalciner 1.71 2.38

0.32
1.25 SO, "mean plus two"
8.62 NOx "mean plus one"
0.06 6.13
Mean 0.84 5.71
St Dev 0.775- 3.141 2.4 8.9
cv 93 % 55 %
St Dev = Standard Deviation
CV = Coefficient of variation; the standard deviation divided by the mean a s a %.

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International, Inc. Draft Subject t o Change

I 1.3 RATIONAL FOR KILN SUBDIVISION

13.1 KILNFUEL
1
Prior to large price increases in fuel cost (mid 1970s and early 1980s) natural gas and oil were often
usedasfuelforcement kilns. Butpriceincreases innatural gas and oil quickly resultedin the cement
industry converting almost exclusively to coal. When the Portland Cement Association polled the
cement industry for source test data for the emission factor update, submissions from approximately
70 source tests since 1977 were preponderantly from kilns fueled with coal; one was from an oil fired
kiln while two kilns were co-fueled with coal and waste derivedfuel. Therefore, testsfmm coal fueled
kilns only were used for estimation of emission factors herein.
13.2 KILN PROCESS CLASSIFICATION
Kilns were divided by manufacturingprocessbecausesuch classification generally reflects a division
by amount offuel used i.e., preheater and precalciner less than long dry and all less than wet process.
Emission oMOXare generally linearly correlated with fuel consumption (combustion N0,ratherthan
fuel or feed NOJ, while sulfur in SOxis often derived from fuel rather than feed. So classification by
a surrogate for fuel consumption is logical.
Further subdivision by dust control devices was not possible due to the small number ofkilnsin each
original classification (by manufacturing process). Initial classification by dust control devices
insteadof manufacturingprocess wouldnotbeappropriate, as this wouldhave resultedin combining
manufacturingprocessesunderdust control devicesthereby loosingthenatural classification by fuel
consumption.
1.4 CRITERIA FOR RATING AND SELECTING DATA
1.4.1 CRITERIA F O R GRADING KILN DATA

I Criteria for grading kiln data were derived in part from EPA's Technical Rocedures for Developing
AP-42 Emission Factors and Preparing AP-42. EPA's grading criteria were:
A Tests performed by a sound methodology and reported in enough detail for adequate
I
validation.
B. These tests are not necessarily EPA reference method tests, although such reference
methods are certainly to be used as a guide.
C. Tests that are based on an untested or new methodology or thatlack asignificant amount
of background d a t a
D. Tests that are based on a generally unacceptable method but may provide an order of
magnitude value for the source.
The only exclusion criteria relevant to data submission were:
(1) Fuel other than coal used during the test.
(2) Test series averages reported in units that cannot be converted to the selected reported
units.
EPA recommended combining data of Grades A and B if there were not sufficient tests of Grade A
to estimate emission factors; this recommendation was followed. Most source tests were Grade B
which were combined with Grade A data for estimates of emission factors (See Table I).
While not specified as an exclusion criteria, widely varying replicate measurements were suggested
as a basis for giving data a lower grade. Here, tests from the same kiln were excluded if replicates
within the same test varied by more than 100% unless emissions were very low (average less than
2.0 l b o ) and it tests within the same year varied by more than 500% unless information concerning
a change in either fuel or raw fuel could explain the variation.

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1.4.2 KILN DATA MCLUSIONS

Data from two kilns were excluded from use in estimates of emission factors (Table I). Data from
Oklahoma Cement in Pryor (Reference 6) was excluded as SO, emissions varied by more than 100%
within the same test. Data from Gifford-Hill's #3 kiln a t Midlothian (Reference 20)were excluded.
NO, replicates in 1978varied by more than 100%. and repeated tests in 1985for SO, varied by more
than 500% for which there was no reasonable hypothesis.
All other data in Table I were employed in estimates of emission factors. Comments to the data
provide information regarding specific use of source test data.
1.5 PROPOSED CEMENT KILN SOJNO, EMISSION FACTORS (COAL FUEL
ONLY)
Based on the data available and the criteria discussed in this document Table I11 is the paoposed
emission factors.
Table III
Proposed Emission Factors
Kiln Type SOxlbslr (kgs/MT) NO* lbdr ( k g m )
Long Dry
Wet Process
Preheater
Precalciner

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DATA REFERENCES
1
The references of the sources of data and comments regarding the data are supplied below.
L DRY PROCESS
1. CalMat Colton #s 13;1 e t t e r h m D a v i d Cahn to Frank Noonan, EPA, NC, re: AP-42
Factorsfor GaseousEmissionsfrom PortlandCementKilns, June2,1987;attached: data
for Feb., Mar., April, 1987.
2. Gifford-Hill, Riverside (Crestmore); Gerald L. Young and John Croom, Technical
report on the demonstration of the feasibility of NOx emissions reduction a t Riverside
Cement Company, Crestmore Plant", January 13, 1986.
3. Gifford-Hill, Riverside (Crestmore); JC memo: 'Crestmore SOX data reduction,
Daily Averages from continuous monitor", no date.
4. LaFarge, Alpena; Clayton Environmental Consultants, Inc., Tmission study of the
Cement Kiln 20 Baghouse Collector a t Alpena Plant, Great Lakes Division LaFarge
Corporation, Alpena, Michigan," proj.# 22105.00, March 8,1989; and "EmissionTesting
of Dust Collectors on Kiln I a t Lafarge Corporation, Paulding, Ohio," proj.# 23857.00.
5. Lehigh, Waco; Mullins Environmental Testing, Inc., "Source emissions survey Or
Lehigh Portland Cement Co., Waco, Texas," File No. 83-69; August, 1983.
6. Oklahoma Cement, Pryor, Mullins Environmental Testing, Inc., 'Source Emissions
Survey of Oklahoma Cement Company Kiln Number3 Stack, Pryor, Oklahoma," File No.
80-38.
.., March.
- 1980.
--- .--,
--.
-~

7. SW, Black Mt.; Truesdail Labs., Inc., "Report: Sampling and Analysis for sulfur oxides
(SOX),nitrogen oxides RJOx) and carbon monoxide (CO)in Kiln exhausts", ( V i c t o ~ l l e
#5 & #8; lack Mt. #I); December 5,1980. (SW Victorville, WET, repeated as 21. below)
8. SW, Black Mt.; letter from James Morgester, Air Resources Board, State of California,
to Douglas MacIver, Southwestern Portland Cement Company, August 29, 1984.
Following 3 reports attached:
9. SW, Black Mt; 'Summary of Source Test Results," July 25,1984. :
10. SW,BlackMt.; letter from G.W. 0gletoT.F. Knisley, July 20,1984,Re:NOxTest - June
13, 1984. Attached report "Kiln exhaust a t Black Mountain: SOX,NOx, CO emissions"
July 12, 1984.
11. SW, Black Mt.; 'Baghouse Exhaust a t Black Mountain Kiln #1, Sulfur Oxides and
Nitrogen oxides," August 10, 1984.
11. WET PROCESS
12. Alpha, Cementon, NY;Walter Hinkley, Energy & Resource Recovery Corp., 'Baseline
and solvent fuels stack emissions test." Januarv 25-26.1982.
13. Lehigh, Cementon; RL. Baker, KVB,~nc.,'~implia&e ~ e sResults, t Particulate and
Sulfur Oxide Emissions, Cementon Kiln, prepared for Lehigh Portland Cement Co.,
Cementon, NY,"November 8-9,1984.
14. Lehigh, Waco;TenerxCorp., "Lehigh Portlandcement Co. White Kiln CokeConversion
(TACB permit no. C-9399) Emission Compliance Report (NOX, S02, particulates),"
December 18,1985.
15. L S Florida, Mia& (Pemsuco); letter from Albert Townsend, LoneStar Florida1
P e n n s u c o to Bill Arlington, S o u t h Florida Environmental Services, Inc.;
attached, 'Compliance stack test, LS Florida1 Pennsuco, Inc. Report 3 8 7 3 Kiln No. 3",
July 15, 1981. ,
16. LS,New Orleans; Mullins Environmental Testing Co., Inc., "Source Emissions Survey
of Lone Star Industries, Inc., New Orleans, Louisiana," File No. 81-107, November 10-
13, 1981.
17. LS, New Orleans; Entropy Environmentalists, Inc., "Stationary Source Sampling
Report, Lone Star Industries, Inc., New Orleans, Louisiana, Particulate and Sulfur
Dioxide Emissions Compliance Testing, Kiln #I & #2 Precipitators Outlet Stacks," May
20-21,25, 1982.

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18. LS, New Orleans; Entropy Environmentalists, Inc., "~tationarySource Sampling

1
Report, Lone Star Industries, Inc.. New Orleans, Louisiana. Pollutant Emissions
Experimental Testing, Kiln #I & #2 Stacks," May 20-21,25-26, 1982.
19. LS, New Orleans; Mullins EnvironmentalTesting Co., Inc., "Source Emissions Survey
of Lone Star Industries, Inc., Kiln Number I Stack, New Orleans, Louisiana," File No.
84-39, March, 1984.
20. Gifford-Hill, Midlothian, TX; letter from Don Sinkular to QA, Inc. Dec. 18,1989.
21. St. Marys Peerless Cement, Detroit, MI; letter from Gerald Young to John Croom.
Dec. 13, 1989.
22. SWVictorville;Truesdail Labs., Inc., "Report: Sampling and Analysisfor sulfur oxides
(SOX),nitrogen oxides WOx) and carbon monoxide (CO) in Kiln exhausts", ( V i c t o ~ l l e
#5 & #8; Black Mt. #I); December 5,1980.
23. SW Victorville; letter from Douglas MacIver, Southwestern Portland Cement Co., to
Walter Mook, Air Pollution Control, CA, re: NOx, SOXand CO concentrations on Kilns
No.'s 6 , 7 and 9, August 22,1980. (Attached report, Truesdail Laboratories, August 20,
1980)(see ref #7 above).
m. PREHEATER
24. Ashgrove, Durkee; letter from Richard Cwke, Ash Grove Cement West, Inc. to Frank
Noonan, EPA, NC, May 13,1987; attached 1)&&-"Cement reports issue," July,
1980; and 2)Horizon Engineering, "NOx Emission Test Report, Ashgrove Cement West,
Inc., Durkee, Oregon Cement Plant," September 15,1985.
25. Calaveras, Redding, CA; letter from Stan Cramer, Calaveras Cement Co. to Frank
Noonan, EPA, NC, re: A€-4'2 Factors for Gaseous Emissions from Portland Cement
Plants, May 13,1987.
26. Lehigh,Buda,TX;MullinsEnvironmentalTesting Co., Inc.."SourceEmissionsSunrey
ofTexas Cement Company, Buda, Texas," File ~ o r 8 6 - 4 8June, , July, 1986.
27. LS Davenport, CA; L.A Johnson, Chemecology Corporation, "Field Data Source Test,
prepared for Lonestar Industries, Davenport, CA, regarding Particulate, NOx and SO,
Emissions," May 13, 1982.
28. LS Maryneal, TX; letter from Billy Mullins, Mullins Environmental Testing Co., Inc.
to Roy Blankenship, Lone Star Industries, Inc., July 29, 1980; attached report: Source
Emissions Survey, June 20, 1980.
29. SW Fairborn, OH, Franklin Meadows, Pollution Control Science, Inc., "Determination
of particulate and sulfur dioxide emissions from the kiln and alkali baghouse stacks,
Southwestern Portland Cement Company, Fairborn, Ohio,: June 10.12.1986.
30. SW; letter from Doug MacIver, Southwestern Portland Cement Co. to John Croom,
October 23,1989; attached reports, 29,30,31:
31. SW Florida Mining #2;letterfromMattStone, FloridaMining8zMaterialsto MacIver,

32.
.
re: Source Test Emissions., Se~tember 19. 1989:,r e ~ o r on
~ ~ ~ o s m o s d a l e , m ' ~ o u r csummary,
r .
t NOX S02.
---
e ~ e s t Kosmos, Louisville Kiln," June 6-8,1989.
33. SW Odessa,TX;"Summary ofsource emissions surveys, Southwestern Portland Cement
Co., Odessa. Texas Plant -kiln #2 Stack," ~ebruary,-19.83.
34. SW Odessa,TX; letter from John Mummert, Southwestern Portland Cement Co. to Bill
Stewart,Texas Air Control Board, re: Compliance test submittal for construction permit
No. C-8411, April 14, 1983; attached report: Mullins Environmental Testing Co., Inc.,
"Source Emissions Survey of Southwestern Portland Cement Company Kiln number 2
stack, Odessa, Texas," File No. 83-09, February, 1983.
I v. PRECALCINER
35. Ash Grove. Learnington, UT;letter from Stephen Sheridan, Ash Grove Cement West,
Inc. to John Croom, re: NOx testing at Leamington, Utah plant, January 15, 1980;
'attached report.

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CalMat, Mojave, CA; letter from David Cahn, CalMat Co. to John Croom, rc: CEM
emissions data summaries, Colton plant, December 18,1989;attached report: Vernon
1
McKnight, Pape & Steiner Environmental Services,"MojavePlant(Kiln, Clinker Cooler,
and Crusher Baghouses) Annual Compliance Test," May 15,16and 17,1989.
Marquette, Cape Girardeau; Performance Testing & Consultants, Inc., "Source
Emissions ComplianceTest Report on the Kiln Stack, Marquette Cement Manufacturing
Company, Cape Girardeau, Missouri," February, 1982.
LS,Cape G i d e a u ; B.W. Doyle and RL. Baker, KVB, "Assessment of sulfur levels,
Cape Girardeau, MO, prepared for Lone Star Industries," January, 1984.
SW Leamington; letter from Douglas MacIver of Southwestern Portland Cement Co.
to BrentBradford,UtahAirConservationCommittee, re: Leamington Cement Kiln, July
13,1984;attached report: YorkResearch Consultants, "Plant performance test program
on the kiln and alkali bypass stacks a t the Southwestern Cement Leamington, Utah
Plant," June 21,1984.
SW Victorville 12;Pape & Steiner Environmental Services, "Performance Guarantee
Testing a t Southwestern Portland Cement, February 5 through 8,1985".
SW Victorville #2; Pape & Steiner Environmental Services, 'Compliance Testing a t
Southwestern Portland Cement, March 18 through 21,1985".
SW Victorville #2;Pape & SteinerEnvironmentalSe~ces,"EmissionTests on Quarry
Plant #2 Kiln, February 24,1987".
SWVictorville #2;Pape & Steiner Environmental Services, 'EmissionTests on#2 Kiln
Baghouse, March 32 and April 1,1987".

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