P.1 

OAR Box 1851 

Prepped by Keeia Richards 

Document Number: 

40) ll-A-14 

Docket Number: 

A-90-19 

Printed 11/19/2008 11:19:52 AM Sheet 40 of 41 
P.2 

A-90-19 

ll-A-14 

FPA AIR DOCKET 

Population and Characteristics of 

Industrial/Commercial Boilers in the U.S. 

by 

T. Devitt, P. Spaite, and L Gibbs 

PEDCo Environmental, Inc. 

11499 Chester Road 

Cincinnati, Ohio 45246 

Contract No. 68-02-2603 

Task No. 19 

Program Element No. EHE624A 

M'A I'I<P|IM:I OHic.ni Chiiilnu J dMillyiiim 

Industrial Environmental Research Laboratory 

Office of Energy, Minerals, and Industry 

Research Triangle Park, NC 27711 

Prepared for 

U.S. ENVIRONMENTAL PROTECTION AGENCY 

Office of Research and Development 

Washington, DC- 20460 
P.3 

1 

This report was furnished to the U.S. Environmental 

Protection Agency by PEDCo Environmental, Inc., Cincinnati, 

Ohio, in fulfillment of Contract No. 68-02-2603, Assignment 

No. 19. The contents of this report are reproduced herein as 

received from the contractor. The opinions, findings, and 

conclusions expressed are those of the author and not necessarily those of the Environmental Protection Agency. 

i i 
CONTENTS 

P.4 

Figures 

Tables 

Acknowledgement 

Executive Summary 

1. Introduction 

References 

2. the Industrial/Commercial Boiler Population and 

'Fuel Consumption 

2.1 Boiler Classification 

2.2 Present Boiler Population 

2.3 Fuel Consumption 

2.4 Growth Projections for Industrial/Commercial 

Boiler Population 

References 

3. Atmospheric Emissions 

3.1 Emission Factors 

3.2 Current Levels of Uncontrolled Emissions 

3.3 Emission Projections to 2000 

References 

4. Representative New Boilers and Characteristics 

4.1 Typical Industrial Boilers 

4.2 Boiler Characteristics 

References 

5. Basis for Cost Evaluations 

5.1 Cost Elements 

5.2 Cost Estimating Format 

5.3 Unit Cost Recommendations 

References 

Page 

vii 

viii 

xiii 

xiv 

1 

5 

6 

8 

29 

37 

51 

52 

52 

69 

76 

87 

88 

88 

91 

111 

112 

113 

118 

123 

125 
P.5 

SECTION 2 

THE INDUSTRIAL/COMMERCIAL BOILER POPULATION AND FUEL CONSUMPTION 

The population of industrial/commercial boilers consists of 

many different types of units, which use various fuels and 

methods of heat transfer. The following subsections present the 

categories of classification for industrial/commercial boilers, 

the population of each category, tho fuels consumed in each 

category, and the projections of growth of fuel consumption by 

the boiler population through the year 2000. 

2.1 BOILER CLASSIFICATION 

Boilers can be and have been classified in a number of ways, 

using such bases of categorization as boiler type, fuel use, and 

method of manufacture. Two main factors were considered in 

selecting the parameters of classification for this study. 

First, consideration was given to whether variation in the parameter was likely to produce a significant change in air emissions. The second consideration asks whether the parameter had 

been regarded as an important variable in collecting and storing 

the data needed to construct boiler population estimates. The 

final list of parameters was developed from analysis of past work 

and reflects comments of reviewers who are associated with boiler 

manufacturing organizations and know what data are available. 

The basic boiler classifications appear in Table 2-1. As 

the table shows, units were categorized by construction method 

and heat transfer configuration, then by firing mechanism and 

fuel. Descriptions of the various types of boilers shown in 

Table 2-1 are presented in Appendix A. 

Each type of industrial/commercial boiler was further 

subcategorized by heat transfer mechanism, type of use, and size, 

using the following classification scheme. 

6 
P.6 

TABLE 2-1. CATEGORIES OF INDUSTRIAL/COMMERCIAL BOILERS 

Field-erected/Water-tube 

Pulverized coal 

Spreader-stoker 

Overfeed-stoker coal 

Underfeed-stoker coal 

Residual oil 

Distillate oil 

Natural gas 

Package Boilers/Water-tube 

Pulverized coal 

Spreader-stoker coal 

Overfeed-stoker coal 

Underfeed-stoker coal 

Residual coal 

Distillate oil 

Natural gas 

Package/Fire-tube 

Coal/Horizontal Return Tubular (HRT) 

Coal/Firebox 

Coal/Scotch 

Coal/Other 

Residual oil/Horizontal Return Tubular (HRT) 

Residual oil/Fi::ebox 

Residual oil/Scotch 

Residual oil/Other 

Distillate oil/Horizontal Return Tubular (HRT) 

Distillate oil/Firebox 

Distillate oil/Scotch 

Distillate oil/Other 

Natural gas/Horizontal Return Tubular (HRT) 

Natural gas/Firebox 

Natural gas/Scotch 

Natural gas/Other 

Package/Cast Iron 

Coal 

Residual oil 

Distillate oil 

Natural Gas 
P.7 

Heat transfer medium: 

Supercritical steam 

High-pressure steam 

Low-pressure steam 

Hot water 

Use: 

Commercial/institutional space heating 

Industrial space heating 

Industrial process heat 

Size: 

MW thermal (Btu/h) 

Equal to or under 0.1 

Over 0.1 - 0.4 

Over 0.4 - 2.9 

Over 2.9 - 7.3 

Over 7.3 - 14.7 

Over 14.7 - 29.3 

Over 29.3 - 73.3 

Over 73.3 - 146.5 

Over 146.5 - 439.5 

Over 4 39.5 

(Equal to or under 0.4 x 106) 

(over 0.4 x 106 - 1.5 x 106) 

(over 1.5 x 106 - 10 x 106) 

(over 10 x 106 - 25 x 106) 

(over 25 x 10& - 50 x 106) 

(over 50 x 106 - 100 x 106) 

(over 100 x 10^ - 250 x 106) 

(over 250 x 106 - 500 x 106) 

(over 500 x 10^ - 1500 x 10^). 

(over 1500 x 106) 

Possible combinations of the classifications used in this 

study are illustrated in Figure 2-1. 

During the course of the study, many rearrangements of the 

data were used to compare the relative significance of various 

categories, with regard to such factors as total capacity, fuel 

consumption, and emissions. The next section describes the 

boiler population according to the final classifications selected. 

2.2 PRESENT BOILER POPULATION 

Estimates of the number and capacity of present industrial/ 

commercial boilers are derived from combining data in studies by 

Battelle (Locklin et al., 1974; Putnam et al., 1975) and Walden 

(Ehrenfeld et al., 1971) with sales records of the American Boiler 

Manufacturers Association (ABMA) and the Hydronics Institute 

(HI) . 

The total number of boilers categorized by fuel type, size, 

type of use, heat transfer configuration, and method of construction 

8 
P.8 

PULVERIZED 

WATEHyii 

FIELD-ERECTED 

•PACKAGE 

COAL 

RESIDUAL OIL 

DISTILLATE OI 

NATURAL GAS 

STOKER 

L 

SPREADER 

OVERFEED 

UNDERFEED 

FIRE-TUBE f " 

PACKAGE 

COAL 

RESIDUAL OIL 

DISTILLATE OIL 

NATURAL GAS 

HORIZONTAL RETURN TUBULAR 

SCOTCH 

FIREBOX 

OTHER 

COAL 

PACKAGE 

CAST IRON 

RESIDUAL OIL 

DISTILLATE OIL 

NATURAL GAS 

Figure 2-1. Possible combinations of characteristics 

associated with U.S. industrial/commercial boilers. 
P9^ 

(i.e., package versus field-erected) are discussed in the following subsections. The methods used to develop the estimates are 

explained in Appendix B. Data sheets for all boiler types and 

subcategories are presented in Appendix C. 

The total number and capacity of industrial/commercial 

boilers according to fuel used are shown in Table 2-2. The 

various fuels are burned in boilers that differ widely in size, 

use (e.g., space heating and electric generation), and type of 

hardware (e.g., fire-tube, water-tube, and cast iron). In order 

to focus on these differences, it is necessary to examine various 

subcategories. The nonutility boilers being considered can be 

separated into two broad sectors, commercial and industrial. 

Commercial boilers are generally the smaller of the two, and are 

used primarily for space heating in commercial and institutional 

buildings. Industrial boilers are used to generate process 

steam, space heating, and electricity. The distribution between 

the two sectors is shown in Table 2-3. 

TABLE 2-2. SUMMARY OF THE TOTAL BOILER POPULATION BY FUEL USED 

Fuel 

Coal 

Residual oil 

Distillate oil 

Natural gas 

Number of boi 

214,400 

389,104 

244,206 

954,350 

lers 

Total 

MW thermal 

239,110 

358,570 

127,040 

588,590 

capacity,3 

(106 Btu/h) 

(815,830) 

(1,223,800) 

(433,600) 

(2,008,800) 

Throughout this section totals for capacity do not always agree 

because figures are rounded. 

TABLE 2-3. DISTRIBUTION OF NONUTILITY BOILERS BY SECTOR 

Sector 

Commercial 

Industrial 

Number of boilers 

1,295,130 

506,930 

Total 

MW thermal 

402,780 

910,480 

capacity, 

(106 Btu/h) 

(1,374,690) 

(3,107,440) 

10 
P.10 

the size of a boiler can directly relate to the 

auantity of pollutants discharged and the feasibility and 

;^c of control, it is necessary to distribute the total economics 

, .iai/commercial population by size. Table 2-4 presents industr-1-

0 

a display. As shown in this table, 1,094,000 MW thermal 

733 800 x 106 Btu/h), or 83 percent of the industrial/com-

;al boiler capacity, is comprised of units whose size is less mercioJ73 25 MW thermal (250 x 10° Btu/h), the lower limit for the 

existing New Source Performance Standards for boilers. 

TABLE 2-4. DISTRIBUTION OF COMMERCIAL/INDUSTRIAL BOILERS BY SIZE 

Size, 

MW thermal (106 Btu/h)' 

Equal to or under 0.1 

(equal to or under 0.4) 

Over 0.1 to 0.4 

(over 0.4 to 1.5) 

Over 0.4 to 2.9 

(over 1.5 to 10) 

Over 2.9 to 7.3 

(over 10 to 25) 

Over 7.3 to 14.7 

(over 25 to 50) 

Over 14.7 to 29.3 

(over 50 to 100) 

Over 29.3 to 7 3.3 

(over 100 to 250) 

Over 73.3 to 146.5 

(over 250 to 500) 

Over 146.5 to 439.5 

(over 500 to 1500) 

Over 439.5 (over 1500) 

Number of 

boilers 

Total capacity, 

MW thermal (10^ Btu/h) 

970,980 

568,415 

208,659 

25,081 

16KJ83. 

1,018 

253 

65 

69,180 

143,820 

240,270 

126,770 

178,350 

147,380 

185,160 

98,280 

56,080 

68,050 

(236,100) 

(490,700) 

(820,000) 

(432,600) 

(608j.700) 

(503,000) 

(632,000) 

(335,400) 

(191,400) 

(232,200) 

11 
A basic and important way to classify boilers is according 

to heat transfer configuration, i.e., water-tube, fire-tube, and 

cast iron. In water-tube boilers, the water being heated flows 

through tubes and the hot gases circulate outside of the tubes. 

In fire-tube boilers, the opposite is true. In cast iron boilers, 

the gas is also contained inside the tubes that are surrounded by 

the water being heated, but the units are constructed of cast iron 

rather than steel. Classification by type is important because 

water-tube boilers are generally much larger than fire-tube or 

cast iron boilers. The potential emissions are different for the 

various types of boilers. 

Tables 2-5 through 2-7 provide the distributions for the 

three types of boilers according to the size range and fuel used. 

It will be noted that Table 2-5 provides a subcategorization forcoal-fired units according to firing mechanism. In Tables 2-8 

through 2-13, these distributions are presented individually for 

the commercial sector and the industrial sector. 

Table 2-14 summarizes the results and clearly indicates that 

water-tube boilers represent over half the total capacity. 

Furthermore, the average size of water-tube boilers exceeds that 

of fire-tube boilers by more than 10 times. 

In summary, the derived data indicate the following characteristics of the boiler population: 

° Natural gas is the predominant fuel, accounting for 4 5 

percent of the capacity. 

0 Ranking of the other fuels by capacity is residual oil 

at 27 percent, coal at 18 percent, and distillate oil 

at 10 percent. 

0 Distribution of the industrial/commercial boiler population is 69 percent of the capacity in industrial 

applications and 31 percent in commercial applications. 

0 Forty percent of the industrial/commercial boiler 

capacity is in the range of 1 to 73 MW thermal. Seventeen percent of the capacity is above 73 MW thermal, 

and 44 percent is below 7 MW thermal. 

12 
TABLE 2-5. DISTRIBUTION OF U.S. WATER-TUBE BOILERS 

BY CAPACITY AND FUEL TYPE 

u> 

ra. 1 

MlMaSat of onlto 

tota l capacity. MM 

tkaimal <I0« •»«/»» 

Mtaakar of wil l 

Total capacity. MM 

tharaal 110* ato/ M 

waaarlaoo-atoaoi coal 

Mariaa! of ualt a 

SotAl rapacity . MM 

tharaal (10* Otu/a.) 

Oaatfaoa-atoaat coal 

MMMOJOK of ualt a 

Total capacity. "•» 

tharaal UO* ata/b.) 

•aolaual oi l 

Kao n of ualt a 

•aaa l capacity. MM 

tharaal (10* Ma/k l 

Olatlllat a oi l 

Muafear of ualt a 

Total capacity. I9t 

tharaal IIO * Mto/kl 

Natural aa* 

MufUaar of aalt a 

Total capacity. MM 

tharaal 110* Otu/hl 

Total al l foal * 

Muasac of ualt a 

Total capacity. MP 

tharaal 1100 Otu/al 

0 J to 0.4 

10.4 to 1.1) 

0 

• 

111 

ISO 

IS00I 

10 

10 

1.171 

410 

11.4001 

1.010 

l.OI O 

O.SOOI 

1.414 

oso 

11.0001 

7.071 

1.410 

10.1101 

0.4 to 1. * 

I I S to 101 

0 

101 

ISO 

1100) 

010 

1.410 

14,0001 

114 

too 

14001 

1.1IS 

4.010 

II*.»00 l 

1.410 

1.440 

III.OOO) 

1.014 

4.010 

lit.000 1 

10.014 

•4.OSO 

ISI.000 I 

1.0 lo 7. 1 

110 to 1SI 

0 

; 141 

' 710 

; 12.4001 

1 •*' 

1.110 

1 111.0001 

Of 

440 

\ 11.1001 

1.111 

11.010 

144,4001 

410 

2.0*0 

110.1001 

1.111 

11.4)0 

141.1001 

4.Oi l 

11.000 

llll.100 1 

Capacity ranqa 

7.1 to 14.7 

111 to 101 

0 

i„T 

1.010 

110.0001 

1.100 I 

14.740 / 

117.10011 

1 I 

401 j 

4.410 

111.1001, 

1.011 

11.140 

11*2.0001 

014 

0.110 

111.0001 

4.001 

12.710 

1170,0001 

11.211 • 

141.400 < 

1404.7001 

14.7 to 11.1 

110 to 1001 

* 

141 

7.440 

121,4001 

•so 

20,000 

171.0001 

240 

1.170 

110.1001 

2.201 

47.110 

11*2.2001 

200 

4.110 

122.0001 

2.70S 

10.140 

1201.2001 

*.4« 0 

147.140 

1101.000) 

MM tharaal 110* Otu/h) 

l«. l to 71.1 

1100 to 110) 

4*1 

10.110 

170.00*1 

104 

11.1*0 

111.700) 

100 

7.110 

121.700) 

00 

1.700 

112,000) 

1.217 

11.120 

1102.00*1 

202 

0.010 

110,200) 

1.104 

40.100 

1217.1001 

4,14* 

1*1.140 

1*11.0001 

71.1 to 14*.1 

1110 to 1001 

101 

10.4*0 

141.000) 

01 

7.100 

111.(00) 

10 

1.4*0 

111.000) 

I t 

2,110 

10.0001 

100 

20.240 

I00.M0 I 

41 

4.210 

114.1001 

1 1 * 

12.*** 

(1)1.404) 

1.0)4 

40,100 

(1)1.400) 

114.1 to 411.1 

1100 to 1100) 

41 

11.** * 

147.7*4)1 

• 

2.14* 

(7.10*1 

1.110 

O.OOO) 

1 

7 1 * 

12.IM ) 

• 2 

11.0*0 

l«».40*1 

7 

1.12* 

11.1001 

101 

22.1*0 

177,100) 

211 

It.00 0 

11*1.4001 

1 

41*. 1 1 

II1001 

11 

7.710 

11*.4*0) 

1 

1,010 

14.1441 

1 

010 

11.1001 

1 

11.14*1 

0 

1.41 * 

11*.144) 

1 

470 

12.1001 

40 

10.4)0 

|171.*0() 

41 

40.010 

17)2,10*) 

Total . 

711 

**.4« * 

1207.1001 

1.700 

47.110 

1141.100) 

4.000 

11.I* * 

11*0.000) 

1.001 

II.*1 * 

141.0)01 

11.011 

111.410 

(711.700) 

0.000 

10.744 

1112.100) 

14,141 

104.440 

11.011.000) 

10.4*1 

747.4)0 

11.111.110) 
pTABLE 2-6. DISTRIBUTION OF U.S. FIRE-TUBE BOILERS 

BY CAPACITY AND FUEL TYPE 

Fuel 

Size range, MW thermal (10 ' ntu/h) 

0.1 to 0.4 

(0.4 to 1.5) 

0.4 to 2.9) 

(1.5 to 10) 

2.9 to 7.3 

(10 to 25) 

7.3 to 14.7 

(25 to 50) Totals 

Coal 

Number of units 

Total capacity, MW 

thermal (10& Btu/h) 

Residual oil 

Number of units 

Total capacity, MW 

thermal <10& Btu/h) 

Distillate oil 

Number of units 

Total capacity, MW 

thermal (106 ntu/h) 

Natural gas 

Number of units 

Total capacity, MW 

thermal (10° Btu/h) 

Total all fuels 

Number of units 

Total capacity, MW 

thermal (10& Btu/h) 

19,227 

5,630 

(19,200) 

46,267 

13,570 

(46,300) 

30,191 

8.850 

(30,200) 

83.483 

24,470 

(83,500) 

179,168 

52,520 

(179,200) 

5,210 

8,790 

(30,000) 

21,511 

34,630 

(118,200) 

14,089 

22,680 

(77,400) 

33,577 

54.620 

(186,400) 

74,387 

120.720 

(412,000) 

1,533 

7,8 00 

(26,800) 

5,072 

26,050 

(88,900) 

3,318 

17,050 

(58,200) 

8,345 

42,840 

(146,200) 

18,268 

93,790 

(320,100) 

358 

3.930 

(13,400) 

833 

9,140 

(31,200) 

543 

5,980 

(20,400) 

1,518 

16,700 

(57,000) 

3,252 

35,750 

(122,000) 

26,328 

26,200 

(89,400) 

73,683 

83,390 

(284,600) 

48,141 

54,560 

(186,200) 

126,923 

138,630 

(473,100) 

275,075 

302,780 

(1,033,300) 
UI 

TABLE 2-7. DISTRIBUTION OF U.S. CAST IRON BOILERS 

BY CAPACITY AND FUEL TYPE 

Fuel 

Coal 

Number of units 

MW thermal input 

(10$ Btu/h) 

Residual oil 

Number of units 

MW thermal input 

(106 Btu/h) 

Distillate oil 

Number of units 

MW thermal input 

(106 Btu/h) 

Natural gas 

Number of units 

MW thermal input 

(106 Btu/h) 

Total all fuel 

Number of units 

MW thermal input 

(106 Btu/h) 

Size 

<0.1 

(<0.4) 

113,287 

6,010 

(20,500) 

203,569 

15,030 

(51,300) 

127,833 

9,430 

(32,200) 

526,291 

38,710 

(132,100) 

970,980 

69,180 

(236,100) 

range, MW thermal (106 Btu/h) 

0.1 to 0.4 1 

(0.4 to 1.5) 

46,760 

12,310 

(42,000) 

71,614 

16,090 

(54,900) 

44,979 

10,080 

(34,400) 

218,819 

50,340 

(171,800) 

382,172 

88,820 

(303,100) 

0.4 to 2.9 1 

(1.5 to 10) 

19,782 

13,270 

145,300) 

24,285 

22,650 

(77,300) 

15,245 

14,210 

(48,500) 

64,026 

54,470 

(185,900) 

123,338 

104,600 

(357,000) 

Total 

179,829 

31,590 

(107,800) 

299,468 

53,770 

(183,500) 

188,057 

33,720 

(115,100) 

809,136 

143,520 

(489,800) 

1,476,490 

262,600 

(896,200) 
.J 

TABLE 2-8 . DISTRIBUTION OF U.S . WATER-TUBE COMMERCIAL BOILERS 

BY CAPACITY AND FUEL TYPE 

ON 

t+ir-i: — 

rua l 

Puluanaaa coal 

Phalli— of ualta 

tota l capacity. 074 

tharaa l II* * otu/k l 

apraaOag-otokor coal 

aaaa i o l ualt a 

Tota l capacity. MM 

tkarma 1 11*4 otu/k l 

Ua»arlood-atokar coal 

Muvihac of ualt a 

ta>tal capacity. 40) 

tharaa l II* * *jta/hl 

Ouarfuaa-atakai coal 

OasHMW of ualt a 

nata l capacity. •*• 

tharaa l 110* *tu/h l 

•>1MM | Oi l 

•UJMMM of ualta 

•Ma i capacity, m 

tharaal II* * ata/h) 

•latlllat a oi l 

*>•**>• of ualt a 

••ta l capacity, rot 

tharaa l II* * *tu/k l 

aatowal aaa 

OaOar of ualt a 

Dotal capacity. MM 

tharaa l II* * *tu/k l 

tota l al l fuala 

BXoaa*t of unit* 

tota l capacity. MM 

tkanaal 1104 atu/b) 

0.1 to 0.4 

10.4 to 1.11 

0 

• 

111 

101 

1)10) 

2* 

1 

12*1 

• 0 * 

14* 

14*01 

1111 

110 

110401 

• 01 

110 

110)0) 

111* 

1110 

117001 

0.4 to 19 

I I . 1 lo 101 

0 

17 

00 

11001 

110 

771 

12.4401 

41 

100 

1110) 

772 

1 . 140 

ll.ttO ) 

1.1*1 

1 . 1*0 

14.720) 

721 

* * 1 

I I . 1*01 

1. 100 

4.400 

111.1*01 

2 * lo 1.1 

110 lo I M 

0 

11 

240 

11*01 

241 

1.1*1 

14.070) 

11 

1*0 

11*01 

710 

1.100 

111.1401 

204 

420 

II.110 ) 

110 

1.440 

11.400) 

1.171 

7.111 

121.1*0) ' 

I j 

7. 1 to 14. I 

111 to SOI 

0 

144 

1.4 10 

11.1701 

421 

4.440 

11*.0201 

I I I 

1.240 

14.2101 

1.40* 

11.000 

111.1001 

102 

1.070 

110.4*0) 

111 

1.000 

110.7*0) 

1.411 

11.4)0 

1107.1*01 

fjrit y r.n-ie. 

14.> to 11. ) 

I'.O to 1001 

0 

SO 

1.241 

14.1201 

142 

J.M S 

112.0701 

42 

* l l 

11.1101 

111 

11.000 

140.1101 

107 

1.411 

10.240) 

200 

1,*1S 

I2r,120 ) 

1.100 

1S.»4S 

1*0.410) 

HW tht-t«*l () 

I V i l.. 71. ) 

1100 to 2S0I 

14 

411 

12.1001 

10 

1.241 

14.4101 

11 

410 

II.HO I 

1 

221 

17701 

140 

0.1) 0 

11*.1201 

12 

2.440 

10.4401 

141 

4.240 

111.1701 

4 I I 

l*.4SS 

147.1401 

0' otu/kl 

7 ) 1 to 144.S 

I2S0 to 1001 

4 

J 

400 

I1.0S0I 

> 

200 

l*S0l 

1 

1*0 

14401 

14 

1.400 

lli.*70 ) 

1* 

1.100 

IS.0*01 

17 

1.410 

112,1*0) 

104 

10.100 

1)4.100) 

144. ". to 4)4.S 

1100 to 1S00I 

0 

0 

0 

• 

* 

1 . 1*0 

14.7401 

) 

411 

11.24*1 

> 

1.1*0 

11.40*1 

I.*! * 

111.14*1 

41*. 1 

111001 

0 

0 

0 

0 

• 

• 

4 

l.** l 

17.1**l 

4 

1,41) 

117.1**) 

Total* 

1 * 

411 

12.1*01 

111 

1.110 

111.11*1 

1.724 

11.410 

117.4401 

170 

1.4)1 

(4.4441 

4.M l 

41.2*0 

1114.140) 

11.17* 

144.»4*> 

1.411 

11.12) 

(104.1001 

11.70* 

1**.)*) 

1)72.4**1 
TABLE 2-9. DISTRIBUTION OF U.S. WATER-TUBE INDUSTRIAL BOILERS 

BY CAPACITY AND FUEL TYPE 

0.1 to 0.4 

10.4 to I.I I 

to 2 4 

1 to 1*1 

2 . * to 7. ) 

I I * to 211 

Capacity tantia. MM tharpal UQ4 *tu/h ) 

1.1 to 14.7 

121 to SOI 

14.7 to 2* 1 

I S* to 1001 

11.1 to 71. 1 

110* to ISO) 

71.) to 144.1 144.1 lo 114.1 

1210 to 100) 1100 to 1100) 

414.1 

11100) 

PuluatlOQM coal 

•uaaor of ualt a 

tota l capacity . MM 

tharaa l III * ata/a ) 

•pcoaaar-ataaor coal 

•aahar of ualt a 

tota l capacity . MM 

tharaal II* * ato/ M 

—aarfaaa-otokac coal 

Murom of ualt a 

fata l capacity . MM 

tharaal II* * Bta/a l 

Ouocfoaa-atokat coal 

•uaaar of oalto 

fata l capacity . <•§ 

tharaa l <l«* ata/fc) 

aaalaual all 

of aalt a 

-

 e!l»- m 

tharaa l II* * Ma/h l 

hlatlllata all 

t a l capacity . MM 

a l lift* ata/a l 

fata l oi l fual a 

tota l capacity . MM 

tharaal 11*4 *tu/h l 

14* 

41 

111*1 

1 

11*1 

77* 

27* 

1*2*1 

1)7* 

4 M 

11*4* 1 

1)21 

1 4 * 

uaMl 

1*1* 

I 140 

M'.SOI 

44 

70 

12201 

410 

4 ) 1 

12.1**) 

II 

•• 

127*) 

2.44 ) 

1.470 

112.14*1 

1.771 

2.000 

11.00*1 

1.441 

l.*l l 

111.4401 

7.41 * 

10.410 

111. HOI 

0* 

410 

11.1101 

414 

2.011 

Il.tM l 

1 * 

2 ** 

1*4*1 

2,*2 I *.*!• 

112.***) 

411 

2,*4 * 

(4.47*) 

2.201 

10.4*0 

117.1001 

1.240 

11.421 

104.710) 

171 

4.200 

114.110) 

1.004 

11.0 70 

141.1(01 

10* 

1.1*0 

110.*7*| 

1.414 

10.140 

ID).410 ) 

4)2 

*.24 * 

121.11*1 

4.12 * 

4*.*I 0 

1140.1101 

10. 101. 

111.1 111 

I II4.4JDI 

201 

4.171 

121.0001 

730 

17,141 

ll*.*10) 

107 

4.411 

111.1*01 

1.414 

11.440 

1121.4101 

1*1 

4.1* 1 

11*.MSI 

l.ftl l 

11.4*1 

1101.000) 

1.4411 

iii.«r , 

1414.)»0I 

4 ) 1 

1*.** 1 

l*7.*00 l 

474 

20.2* 1 

14*.2*0) 

14* 

7.000 

174.140) 

01 

1.111 

112,1)0) 

1,01 * 

44.7*0 

(1)2.0001 

170 

4, 170 

121.7401 

1.441 

4 ) . 120 

1214.I 101 

..i:.. * 

1*1 

10.140 

141.0001 

74 

4.400 

111.1101 

11 

I.110 

1)0.4101 

14 

1.140 

17.1*0) 

1*1 

11.440 

1*4.(1*1 

IS 

2.SS0 

(1.7*0) 

>0 J 

2 4 . 140 

1100.2101 

oo.ftlo 

I ino.tom 

44 

11.440 

141,70*1 

* 

1.24* 

17.7001 

1 

1.110 

11.0001 

1 

110 

11.1001 

1 * 

11.I M 

(41.44*1 

4 

• 41 

I2.t** l 

*• 

21.01 * 

171.7MI 

217 

11.411 

I 174.0101 

I I 

7,710 

124.44*1 

1 

1.010 

I *. IM 1 

I 

* l * 

II.1M 1 

I 

42* 

I2.1M I 

II*.2*0 1 

I 

47* 

I2.1M I 

)« 

11.141 

ID) . 12*1 

41 

42.441 

JH.420 I 

40.0 " 

(70S.0001 

I . >ii 

4 1 . .'00 

1)4 >.»701 

1.014 

44. HO 

1111. 1401 

714 

11.0) 1 

(11.I'O I 

11.(7 1 

174. I 10 

1*01.1401 

4.40 * 

11.140 

((7 . HOI 

11.1)4 

271.11) 

1*1*. 120) 

17.444 

4 '*.H"> 

, : > v sto i 
TABLE 2-10. DISTRIBUTION OF U.S. COMMERCIAL 

FIRE-TUBE BOILERS BY CAPACITY AND FUEL TYPE 

oo 

Fuel 

Coal 

Number of units 

Total capacity, MM 

thermal (10* Btu/h) 

Residual oil 

Number of units 

Total capacity, HW 

the 1 (10* Btu/h) 

pistillate oil 

Number of units 

Total capacity, MW 

thermal (10* Btu/h) 

Natural gas 

Number of units 

Total capacity, MM 

then-al UO * Btu/h) 

Total all fuela 

4 • » 

Number of units 

Total capacity, MW 

thermal (10* Btu/h) 

Size range, MW thermal (10 Btu/h) 

0. 

(0. 

1 to 0.4 

4 to l.S) 

13,459 

3,940 

(13.S00) 

15,731 

4,610 

(15,700) 

16,001 

4,690 

(16.000) 

30,889 

9,050 

(30,900) 

76,080 

22,290 

(76,100) 

0.4 to 2.9 

(1.5 to 10) 

2,866 

4,830 

(16,500) 

5.163 

8,310 

(28.400) 

5.636 

9,070 

(31,000) 

6,715 

10.920 

(37.300) 

20,380 

33,130 

(113,200) 

2.9 to 7.3 

(10 to 25) 

567 

2,900 

(9,900) 

1.319 

6,770 

(23,100) 

1,029 

5,290 

(18.000) 

1,085 

5,570 

(19,000) 

4,000 

20,530 

(70,000) 

7.3 to 14.7 

(25 to 50) 

100 

1,100 

(3,800) 

233 

2,560 

(8,700) 

179 

1.970 

(6,700) 

167 

1,840 

(6,300) 

679 

7,470 

(25,500) 

Totals 

16,992 

12.770 

(43.700) 

22,446 

22,250 

(75.900) 

22.845 

21.020 

(71,700) 

38,856 

27,380 

(93.500) 

101.139 

83,420 

(284,800) 
TABL E 2-11 DISTRIBUTIO N OF U.S . INDUSTRIAL FIRE-TUBE BOILERS 

BY CAPACIT Y AND FUE L TYP E 

h-t 

Fuel 

Coal 

Number of units 

Total capacity, MW 

thermal (10* Btu/h) 

Residual oil 

Number of units 

Total capacity, MW 

thermal (10* Btu/h) 

Distillate oil 

Number of units 

Total capacity, MM 

thermal (106 Btu/h) 

Natural gas 

Number of units 

Total capacity, MW 

thermal (10* Btu/h) 

Total all fuels 

Number of units 

Total capacity. MW 

thermal (10* Btu/h) 

0.1 to 0.4 

(0.4 to 1.5) 

Size range, MW thermal (10 Btu/h) 

2 

5,768 

1,690 

(5,700) 

30.536 

8,960 

(30,600) 

14,190 

4,160 

(14,200) 

52,594 

15,420 

(52,600) 

103,088 

30,230 

(103.100) 

0.4 to 2.9 

(1.5 to 10) 

2,344 

3.960 

(13,500) 

16,348 

26,320 

(89,800) 

8.453 

13,610 

(46,400) 

26,862 

43,700 

(149,100) 

54,007 

87,590 

(298,800) 

.9 to 7.3 

(10 to 25) 

966 

4,950 

(16,900) 

3,753 

19,280 

(65,800) 

2,289 

11.760 

(40,200) 

7,260 

37,270 

(127,200) 

14,268 

73,2fi0 

(250,100) 

7.3 to 14.7 

(25 to 50) 

258 

2,830 

(9,600) 

600 

6,580 

(22,500) 

364 

4,010 

(13,700) 

1,351 

9,230 

(50,700) 

2,573 

28,280 

(96,500) 

Totals 

9,336 

13,430 

(45,700) 

51,237 

61,140 

(208,700) 

25.296 

33.540 

(114.500) 

88,067 

111,250 

(379,600) 

173,936 

219,360 

(748,500) 
Table 2-12. DISTRIBUTION OF U.S. COMMERCIAL/INSTITUTIONAL 

CAST IRON BOILERS BY CAPACITY AND FUEL TYPE 

~l 

ro 

o 

• 

Fuel 

Coal 

Number of units 

MW thermal input 

(106 Btu/h) 

Residual oil 

Number of units 

MW thermal input 

(10* Btu/h) 

Distillate oil 

Number of units 

MW thermal input 

(10* Btu/h) 

Natural gas 

Number ot* units 

MW thermal input 

(106 Btu/h) 

Total all fuel 

Number of units 

MW thermal input 

(106 Btu/h) 

Size 

<0.1 

(<0.4) 

90,630 

4,810 

(16,400) 

162,855 

12,010 

(41,000) 

102,266 

7,530 

(25,700) 

421,033 

30,970 

(105,700) 

776,784 

55,320 

(188,800) 

range, MW thermal (106 Btu/h) 

0.1 to 0.4 

(0.4 to 1.5) 

37,408 

9,840 

(33,600) 

57,291 

12,860 

(43,900) 

35,983 

8,090 

(27,600) 

175,055 

40,260 

(137,400) 

305,737 

71,050 

(242,500) 

0.4 to 2.9 

(1.5 to 10) 

15,826 

10,610 

(36,200) 

19,428 

18,140 

(61,900) 

12,196 

11,370 

(38,800) 

51,221 

43,570 

(148,700) 

98,671 

83,690 

(285,600) 

Total 

143,864 

25,260 

(86,200) 

239,574 

43,010 

(186,800) 

150,445 

26,990 

(92,100) 

647,309 

114,800 

(391,800) 

I 

1.181,192 

210,060 

(716,900) 
to 

TABLE 2-13. DISTRIBUTION OF U.S. INDUSTRIAL CAST IRON BOILKRS 

BY CAPACITY AND FUEL TYPE 

Fuel 

Coal 

Number of units 

Total capacity, MW 

thermal (106 Btu/h) 

Residual oil 

Number of units 

Total capacity, MW 

thermal (10*5 Btu/h) 

Distillate oil 

Number of units 

Total capacity, MW 

thermal (lO^ Btu/h) 

Natural gas 

Number of units 

Total capacity, MW 

thermal (10^ Btu/h) 

Total all fuels 

Number of units 

Total capacity, MW 

thermal (106 Btu/h) 

Size range, MW thermal (10 ntu/h) 

<0.1 

(<0.4) 

22,657 

1,200 

(4,100) 

40,714 

3,020 

(10,300) 

25,567 

1,880 

(6,400) 

105,258 

7,740 

(26,400) 

194,196 

13,840 

(47,200) 

0 . 1 t o 0. 4 

(0. 4 t o 1.5 ) 

9,35 2 

2,46 0 

(8,400 ) 

14,32 3 

3,22 0 

(11,000 ) 

8,99 6 

2,02 0 

(6,900 ) 

43,76 4 

10,08 0 

(34,400 ) 

76,43 5 

17,78 0 

(60,700 ) 

0 . 4 t o 2. 9 

(1. 5 t o 10) 

3,95 6 

2,67 0 

(9,100 ) 

4,85 7 

4,54 0 

(15,500 ) 

3,0 4 9 

2,840 

(9,700 ) 

12,80 5 

10,90 0 

(37,200 ) 

24,66 7 

20,95 0 

(71,500 ) 

35,96 5 

6 , 330 

(21,600 ) 

59,89 4 

10,78 0 

(36,800 ) 

37,61 2 

6,74 0 

(23,000 ) 

161,827 

28,720 

(98,000) 

295,298 

52,570 

(179,400) 
1 

P.21 

TABLE 2-14. BOILER POPULATION DISTRIBUTED BY 

HEAT-TRANSFER CONFIGURATION 

Heat transfer 

configuration Number of boilers 

Total capacity, 

MW thermal (106 Btu/h; 

Water-tube 

Fire-tube 

Cast iron 

50,495 

275,075 

1,476,490 

747,930 

302,780 

262,600 

(2,552,500) 

(1,033,300) 

(896,200) 

22 . 

_^a*J||i _ 
P.22 

Distribution of the industrial commercial boiler 

capacity by the three major types is 57 percent watertube, 23 percent fire-tube, and 20 percent cast iron. 

Given the significance of water-tube boilers, it is appro-

•.•.* to examine further details of the population. priate 

Based on sales data from the ABMA and HI, it was determined 

, t about 20 percent of the water-tube boiler capacity currently 

place is less than 7 years old. (The sales data from ABMA 

wer e available only for the past 7 years). About 25 percent of 

the current capacity of fire-tube and cast iron boilers is less 

than 10 years old. About 62 percent of industrial/commercial 

water-tube boiler capacity is field-erected. The rest are package units (i.e., fabricated in the shop and transported in one 

piece to the plant site). In contrast, all fire-tube and cast 

iron boilers are package units. Tables 2-15 and 2-16 provide a 

distribution of the water-tube boilers by size and fuel type for 

the field-erected and package units. Although there are three 

times as many package units, these only represent a third of the 

total capacity. 

The majority of the total water-tube boiler capacity is 

represented by boilers below 73.3 MW thermal (250 x 106 Btu/h), 

the present lower limit for units subject to NSPS. The distribution by size, (excerpted from Table 2-5) is: 

Size, Total capacity, 

MW thermal (10* Btu/h) MW thermal (1Q6 Btu/h) 

Equal to or under 7.3 

(equal to or under 25) 50,380 (171,800) 

Over 7.3 - 14.7 (over 25 - 50) 142,600 (486,700) 

Over 14.7 - 29.3 (over 50 - 100) 147,380 (503,000) 

Over 29.3 - 73.3 (over 100 - 250) 185,160 (632,000) 

Over 73.3 (over 250) 222,410 (759,000) 

Only 6.7 percent of the total water-tube capacity is below 

7.3 MW thermal (25 x 106 Btu/h). Water-tube units below 73.3 

MW thermal account for nearly 49 percent of the boilers not 

Presently covered by NSPS. 

23 
TABLE 2-15 . DISTRIBUTION OF U.S. FIELD-ERECTED WATER-TUBE BOILERS 

BY CAPACITY AND FUEL TYPE 

talaatlaaa ' coal 

aaaear of *M.I4a 

Vata l capacity . MM 

tharaa l (l» » ata/a t 

aawaa«ar-a4oaar oaal 

aaaaat of aait a 

Tot. I capacity , MM 

tharaa• Il lit (!•*• i tta/k l 

•aaatfaaa-atoaa r coal 

•uraa t of aatt o 

fata l capacity , 414 

tkaiaa l II* * ata/a l 

e—,fao4-atoaa « Si 

ro aaaaat of aalt a 

tota l caaacity . MM 

tharaa l IIP * Ma/k l 

i l al l 

aaaal aapaclty . MM 

taataa l (It * a t a/ a I 

»4»tlllat a al l 

•aaaa i of aalt a 

t l caaacity . MM 

araal lit * •ta/a l 

Matatal w t 

•t of Malta 

•ta/a l 

tota l caaacity . MM 

taaraa l II* * 

tota l al l foot* 

Mtaaaav of wall a 

tota l capacity . W 

taataa l Ila 4 ato/a t 

l'.»l>.city i^iKi*. MW iti-ra^l 1104 otu/hl 

(0.4 to I 

0.4 l o 1 4 

11.1 to 101 

1.4 Iti 1.1 

110 to I M 

41 

210 

(10»l 

1*1 

• 10 

(1.1001 

14 

110 

1400) 

• 1 * 

1.400 

tll.lM l 

1*1 

• t o 

11.0401 

140 

1.100 

tll.tOO ) 

2.041 

».4t 0 

111.4001 

7 .1 to II. 1 14.1 to 24.1 

U S to S0| ISO to 1001 

H I 

1.140 

(••••0 1 

I M 

S.*4 * 

(11.2401 

120 

1.120 

I4.SO0) 

1.401 

14.040 

1*4.4401 

114 

2.1(0 

(».»00l 

1.44 * 

IS.(2 0 

1*4.0001 

l.*10 

41.140 

1144.0001 

120 

1.410 

14.4001 

I I I 

1,410 

llS.SOOl 

( 1 

1.440 

(4.4001 

111 

14.440 

(S4.400I 

104 

2, 140 

••.••0 1 

» 1 * 

20,410 

111.1*01 

2. 14*' 

41,110 

1114.1001 

2*. I i n 11. 1 

1100 to 2*0) 

140 

I S. 140 

IS2.S00I 

17* 

14.100 

I4S.1001 

I IS 

S.4S0 

II*.100 1 

47 

2.14 0 

I*.1001 

411 :».*»• 

1114.440) 

1SI 

4.42 0 

122.4001 

1.14* 

42.110 

111*.100) 

1 . 14* 

II*.41.0 

1414.0001 

11. 1 to 144.S 144.S to 41*.S 

(241 to SOU (SO* to ISO*) 

1*0 

I I . 11* 

141,10*1 

12 

1.41 0 

124,100 ) 

17 

1.400 

(11,41*1 

IS 

2.24* 

(7.7**) 

2 ** 

21.»*» 

(*4.***l 

4* 

4.14* 

114,2*01 

111 

12.100 

(111.000) 

1,00* 

» !. IS * 

llll.*10 l 

11 

141 

2 

11 

1 

(1 

12 

11 

141 

1 

(S 

22 

411 

44 

1*1 

44 

.440 

.10*1 

* 

,240 

.1*0) 

S 

.11* 

,*B*I 

1 

110 

S44) 

42 

• •• 

444) 

1 

414 

104) 

141 

440 

111) 

241 

010 

4011 

4 14.4 

(ISOOI tol a la 

I I 

1,740 

I24.4M ) 

t 

l.*4 * 

I4.1M 1 

I 

• I * 

O.IM 1 

I 

4 2 * 

I1.1M I 

4.41 1 «!*.)•*) 

I 

4 7 * 

U.tao ) 

4 * 

S4.411 

1112, 

*S 

44.*S1 

12)2.2**) 

414 

44.4 10 

(144.100) 

741 

II.10 0 

(110.2001 

1.141 

14.440 

(I).100 1 

124 

4.770 

111.1001 

4.14 1 

124.040 

(424,100) 

774 

ll.*7 0 

144.1001 

4.14 7 

174.4)0 

(417.4001 

12.4) 1 

44..4S 0 

ll.414.ii>0> 
^•'**«***apw*mam*artaawi ll^)U^l"V"l»ll WVMt'.'l •»»*H4t2»»2M^^ 

TABLE 2-16. DISTRIBUTION OF U.S. PACKAGE WATER-TUBE BOILERS 

BY CAPACITY AND FUEL TYPE 

thciiul 1104 itu/hl 

u.l i.. 0.4 

10.4 lo I.SI 

0 4 >•> 2. 4 

I I S t o 101 

2. * to 1.1 

II* to 2SI 

1.1 to 14.1 

I IS to SOI 

14.7 to 2*.I 

IS* to 1*01 

2*. 1 to II. I 

1100 to 2S0I 

11.1 to I44.S 

I2S0 to 4001 

I44.S to 11* . S 

I S M to 1SMI 

41*.S 

11401) 

Pai»at.4aa coal 

aaaaac of oatt a 

fata l capacity. MM 

tharaal (11 * ata/ M 

apraaaat-atoaat coat 

ro 

•MPaat of aalt a 

fata l capacity. MM 

•harai l (I* * ata/h ) 

O.aifaoa'-atotat coal 

Baaaar a f aalt a 

fata l capacity. MM 

tharaal IIP * ata/h l 

•aalaaa l al l 

•aaa i aapaclty. MM 

tharaal II* * ata/a l 

lollllat a al l 

•aahas a f aalt a 

• I capacity. MM 

•raa l »»•* »ta/h | 

•atata l %am 

•aahar a t aalt a 

fata l aapaclty. MM 

tharaal IIP * ata/h l 

fata l al l foal a 

• ill l af aalt a 

fata l capacity. "*» 

al <!•* ata/a l 

S12 

I S * 

ISM I 

1 * 

1 * 

II* ) 

1111 

41* 

II4M I 

2*2* 

1*1 * 

(IS**) 

2414 

• 4* 

I1100I 

707S 

1440 

14 1141 

101 

I',* 

ISM I 

1.410 

14.40*1 

114 

141 

I4M) 

1.214 

4,110 

II*.S M 

2.444 

1.44* 

Ill.tM) 

1.414 

4.410 

114.IM ) 

10.411 

14.140 

141.1MI 

»» 

soo 

II.7M I 

44* 

2.24* 

I1.1M I 

41 

120 

11.111) 

1.412 

4.110 

I1I.IM I 

442 

2.0*0 

I1.1MI 

I.77 S 

1.14 1 

IM.1MI 

4.171 

21.120 

(71.M0) 

144 

4.0 70 

111.400) 

1.044 

11.72* 

I4*.*M > 

2*2 

1.110 

110.4**1 

I.M S 

II.SO* 

llll.OM ) 

440 

4.SI 0 

(22.10*1 

1.404 

14.1*0 

(11S.*MI 

*.24 l 

*t.*2 0 

(140.1001 

22 I 

4.010 

114.S*0) 

417 

11.110 

I4S.M0 I 

142 

1.4*0 

(II.M*) 

1.4 14 

11.110 

I10S.4M ) 

1*1 

4.11 * 

ll«.*0* l 

1,(14 

14.710 

1112.IM) 

4.44 S 

Li].:.... 

i n 

S, 110 

117.4*01 

124 

S. I«0 

II*.400 1 

44 

1.110 

10.4001 

2) 

140 

11.2001 

10* 

I I . 110 

I4S.400I 

41 

2,2 10 

(7,4001 

1*7 

17,400 

IS*.400) 

I .04 7 

(isllooo. 

I 

40 

(1001 

1 

40 

(100) 

I 

40 

I 1001 

I 

40 

llbOi 

2 

2*0 

11*0*1 

1 

40 

1)001 

1 

2*0 

110101 

Mil 

4 

111 

IS. 

141. 

1. 

10. 

1104. 

1 

(27 

11 

44 

(111 

7 

1* 

(41 

11 

107 

1)41 

11 

24) 

(144 

114 

220 

4001 

4IS 

0)0 

1001 

4 1* 

• 40 

200) 

471 

140 

110) 

SOO 

ISO 

4001 

211 

7*0 

SOO) 

414 

410 

1001 

411 

140 

1101 
P.25 

The capacity represented by boilers between 7.3 and 73.3 MW 

thermal (25 and 250 x 106 Btu/h) is large for both field-erected 

and package water-tube boilers. Approximately 93.5 percent of 

the capacity of package boilers is in this range. For fielderected boilers, the distribution is: 

Size, 

MW thermal (106 Btu/h) 

Equal to or under 7.2 (equal to or under 25) 

Over 7.2 - 73.2 (25 - 250) 

Over 73.2 (over 250) 

Total capacity, 

% 

2.1 

50.3 

47.6 

The distribution of capacity by fuel for all water-tube 

boilers (excerpted from Table 2-5) is: 

Fuel 

Total capacity, 

MW thermal (1Q6 Btu/h) 

Natural gas 

Residual oil 

Coal

 ; 

Distillate oil 

306,440 (1,045,900) 

221,410 (755,700) 

181,320 (618,600) 

38,760 (132,300) 

Water-tube boilers account for only 27 percent of the overall capacity of commercial units; the balance comes from firetube and cast iron boilers. 

In summary, the industrial/commercial water-tube boiler 

population has the following characteristics: 

° It represents the majority of total capacity. 

0 It represents the fewest boilers. 

0 The average boiler size is the largest of the 

three types. 

0 The majority of the total water-tube boiler capacity is 

field-erected. 

0 Most units are industrial rather than commercial. 

26 
?_6 presented the total estimated fire-tube capacity 

Tab±e 

d fuel. Only 11.8 percent of this capacity is provided 

siz e a..- 6 y

 " e large r than 7.3 MW thermal (25 x 10u Btu/h). 

w boil e r s 

y

 +- fire-tub e boilers have a capacit y between 0.4 and 7.3 

Host n i C -

mal (1*5

 anci ^ x ^ Btu/h). Water-tube units also i. for some capacity in the small size ranges; but for 

account iul , 

under 7.3 MW thermal (25 x 10 Btu/h), fire-tube units 

boil® 

sent five times as much capacity as water-tube boilers. 

boilers with different heat transfer configurations predominat •„a+-e p in different size ranges, 

Tables 2-10 and 2-11 presented the distribution of fire-tube 

city between commercial and industrial boilers. Approxitely 21 percent of the total commercial boiler capacity comes 

from fire-tube units. Most fire-tube boilers, however, are used 

by industry. 

The total capacity of cast iron boilers was presented by 

size and fuel in Table 2-7. All industrial/commercial units 

below 0.1 MW thermal (0.4 x 10 Btu/h) are cast iron. Above this 

size through 2.9 MW thermal (10 x 10 Btu/h), cast iron and firetube boilers overlap considerably. No cast iron units are larger 

than 2.9 MW thermal (10 x 10 Btu/h). 

Tables 2-12 and 2-13 presented estimates of cast iron 

boiler capacity in commercial and industrial applications. The 

tables show that 80 percent of all cast iron boiler capacity are 

used commercially. It should be noted that this ratio was based 

on estimates by Walden and could not be verified independently in 

this study. The same is true of the fire-tube and water-tube 

boiler distributions discussed previously. In all cases, the 

ratio of commercial to industrial capacity was assumed in this 

study to be independent of fuel. This assumption may have introduced errors in the industrial/commercial distribution but would 

not significantly affect the overall size and fuel distributions. 

The classification of total boiler population by type of 

industry is an important parameter. Sales data from ABMA for 

water-tube boilers sold during the period 1966 to 1977 are classified by the Standard Industrial Classification (SIC). Table 2-17 

27 
P.27 

TABLE 2-17 . DISTRIBUTION BY SIC OF WATER-TUBE BOILERS 

SOLD IN PERIOD 1965 THROUGH 1977 

t i c 

M 

IS 

20 

12 

21 

2* 

21 

21 

10 

)) 

J7 

It 

»> 

12 

M 

• J 

latuatry 

aonaanuf acta , i na 

Officii , •hopping 

cantara. aall a 

rood 

tiitil . aill i 

Loabar and aoed 

producta 

tapir, allia d 

product! 

CMiueili , *lli* 4 

proauctt 

Patrolaua rafinina , 

nlit M indultna i 

tubbar product* 

•naar y aatal 

Triniportitlo n 

Nucalltaoov l 

aanafactarln* 

tpirfiit * 

•aila r raavtl i 

•aaplttli . aMlca l 

aaatar*. Maa * 

•ahaal i aa* 

•alaaroltla * 

ruoi 

Coil 

Oil 

Cat 

t ut tota l 

Oil 

Ca. 

tub tota l 

Coal 

OH 

Gaa 

tub tota l 

Coal 

O i l 

Gat 

tut) toti l 

Coal 

Oil 

614 

tub tota l 

Coal 

OH 

6*4 

>u» tota l 

Coal 

Oil 

6*4 

tub toti l 

Coal 

Oil 

6* 1 

tub tota l 

Oil 

Caa 

tub tot* I 

Coal 

Oil 

Cat 

tub tota l 

Coal 

Oil 

6*1 

oak tota l 

Coal 

OH 

Gai 

tab tota l 

0*1 

tab t*t* l 

O i l 

6*1 

tab tau l 

Caal 

O il 

•44 

fta> tota l 

O M l 

O i l 

a** 

tab tota l 

torn 

Ho. ef boilir i 

24 

14* 

121 

1.20) 

2 

10 

12 

11 

140 

<<• 

4S4 

IS 

124 

244 

405 

) )) 

17 

7) 

14 

121 

114 

2S4 

41 

:os 

MO 

I I ) 

2 

14) 

21) 

) t t 

J) 

104 

1S7 

t 

14 

lie 

1SS 

24 

St 

11) 

2 1 ' 

.'t 

211 

4)4 

•74 

11 

11 

M 

I t 

1 1 * 

21 

I t l 

Tt) 

l.tt o 

-2 

1 4 

l - t 

• 74 

t.t4 0 

Capacity 

ha tharaal input 

(16* It./ M 

412 11,4441 

t.124 (10,1141 

12,1*4 144,0011 

22.200 (7S.74II 

2)4 (ISO) 

1*1 11.0001 

•27 11,100) 

1,114 (1,410) 

1.771 (».457i 

t.)4 4 I)l.tl2 l 

1).2) 2 (4S,l»»l 

5)1 11,UO, 

l.H J lt,S2tl 

1.412 11).441> 

t.)t 7 121,7**. 

I t (*0! 

ttS (1.»»«J 

St) (2.01): 

1.204 14,19*) 

1.1!) 14.7441 

2.111 11).ISO) 

l.tt l (11,147) 

t,)0 ) (21.7S1I 

2,)l t (11.Ill ) 

t,)) 4 tll.tti l 

lt.tt t (SO.01*1 

27.104 (t).lt) ! 

44 (ISO) 

4,)) 4 I21.42S) 

7.)* 4 (25.2111 

11.774 (47.011) 

1.012 13.451) 

1.74C 15.4721 

2.742 (4.4241 

I t t (5401 

1.0*4 ().4)0 1 

1.M 7 (10,47)1 

4,li t (14.7411 

1.272 14.1401 

1,44* (S.014I 

1 2,140 It.4141 

l.tl ) llt.ttt l 

1.0*7 (1.741) 

4.444 (11,*1») 

t.Sl t ()2.414) 

11,17* (S2.144I 

l i t 1440) 

l i t 1440) 

1,142 I),til l 

1.24) 17,724) 

1,414 111,4411 

111 Kit ) 

l.tS l It,11 1 I 

7.11 * (24.M7 ) 

1*.4*4 (It.Mi l 

M I ii.ta*) 

1.11 * 11*.1*4) 

«.** * (It,1*4 ) 

1*,M ) (14.414) 

Itt.tt t 14*7,*7tl 

Papcant 

by ind.atry 

14.2 

0.4 

t . l 

4.4 

0.1 

1.4 

11.7 

t . 4 

1 . * 

1.0 

1.1 

10.4 

• i l 

2 . 1 

1.1 

t . t 

tt. t 

28 
P.28 

bulation of the ABMA sales data by fuel type and SIC 

presenC5 th e nonmanufacturing sector (i.e., commercial/ 

.. Boilers 

coo

e

' ., ar e denoted with a SIC code of zero. 

critutionaD are 

in5 , j-,+-a indicate, the chemical, petroleum refinery, and 

A S the a°t o 

•es are the largest purchasers of new water-tube industr J.C 

nrf the chemical industry purchased twice the capacity of ilers,

 an a 

ther two industries. 

food 

bo 

the o 

2 3 . FUEL CONSUMPTION 

The major fuels consumed by industrial and commercial 

are- coal, residual oil, distillate oil, and natural gas. jailers «*iC 

the other fuels burned are wood wastes, liquified petroleum 

asDhalt, and kerosene. Since the four major fuels congaS; asp 

•tute the vast majority of all fuels burned (estimated at 

eater than 90%)/ and since the use of other fuels is sitecific ancj difficult to document, the consumption figures of 

onlv the four major fuels were compiled and analyzed. 

Figures for the consumption of fuel in industrial/commercial 

boilers were derived from statistical reports compiled by the 

Department of Energy. The procedure is fully described in 

Appendix D. 

The summary presented in Table 2-18 shows that gas is the 

most widely used boiler fuel, and that residual oil is burned in 

industrial/commercial boilers in greater quantities than coal. 

TABLE 2-18, ANNUAL FUEL CONSUMPTION BY INDUSTRIAL/ 

COMMERCIAL BOILERS 

Fuel type 

Gas 

Residual oil 

Distillate oil 

Coal 

Total 

Total energy, 1015 J (1012 Btu) 

6,734.5 (6,381.2) 

1,861.0. (1,762.3) 

1,192.9 (1,129.6) 

1,163.3 (1,101.6) 

10,951.7 (10,374.7) 

29 
TABLE 2-19. ESTIMATED FUEL CONSUMPTION BY 

INDUSTRIAL AND COMMERCIAL BOILERS, 197 5 

u> 

o 

Sector 

Industrial 

Coal 

Residual oil 

Distillate oil 

Natural gas 

Total 

Commercial 

Coal 

Residual oil 

Distillate oil 

Natural gas 

Total 

Consumption 

Quantity 

33,906 Gg (39,374 x 103 tons) 

19,881 x 103 m 3 (125,067 x 103 bbl) 

7281 x 103 m3 (45,799 x 103 bbl) 

112,237 x 106 m3 (3,963,635 x 106 ft3) 

4575 Gg (5,043 x 103 tons) 

24,657 x 103 m3 (155,103 x 103 bbl) 

23,521 x 103 m3 (147,959 x 103 bbl) 

64,233 x 106 m3 (2,268,128 x 106 ft3) 

Heat content, 

1 01 5 Joules (1012 Btu) 

1031.0 (976.5) 

830.8 (786.7) 

282.0 (267.0) 

4282.3 (4058.8 ) 

6426.1 (6089.0) 

132.1 (125.1) 

1030.2 (975.6) 

910.9 (862.6) 

2452.5 (2322.4) 

4525.7 (4285.7) 
P.30 

rther distribution into industrial and commercial sectors 

. . industrial boilers consume more fuel overall (a little 

tha»- *• 

*

nt"" fl percent of the total) but that commercial boilers do con-

°

V substantially to total consumption, and that they use a 

rable am0 unt of "dirty" fuel (i.e., coal and residual 

These data are presented in Table 2-19. 

The figures for consumption of major fuels were subdivided 

ndustrial consumption into quantities used for generation of 

tricity* process steam, and space heating. The distribution 

based upon end-use-fuel estimates obtained from the Departof Energy survey of Major Fuel Burning Installations (MFBI), 

cons 

oil) 

(DOE, 

197.5) . These end-use distributions were applied to the 

tal industrial fuel consumption figure, reported in the Mineral 

industry Surveys (Bureau of Mines, 1976 a, b, c) using the procedures described in Appendix D. The results are shown in Table 

2-20. 

TABLE 2-20. FUEL CONSUMPTION FOR INDUSTRIAL BOILERS 

=-" — 

Fuel 

Coal 

Residual oi l 

Distillat e oi l 

Natural ga s 

Tota l enerq 

Electri c 

generatio n 

257. 8 (244) 

108. 8 (102) 

38. 4 (36) 

475. 8 (451) 

880. 8 (833) 

15 12 

y , 10 1 D J (lO1^ 

Process _ 

steam 

618. 6 (586) 

606. 5 (574) 

90. 8 (86) 

3330. 6 (3157) 

4646. 5 (4403) 

Btu) 

Space 

hea t 

154. 6 (147) 

115. 5 (111) 

152. 8 (145) 

475. 8 (451) 

898. 7 (854) 

The MFBI data, however, are less than completely satisfactory. Only boilers having a capacity over 29 MW (100 x 10 

Btu/h) were included, and the number of boilers (3670) was 

limited. All the boilers in this size range are water-tube 

boilers, and the present study estimates that 5603 water-tube 

boilers have a capacity greater than 29 MW (100 x 10 Btu/h). 

Thus, the DOE survey accounted for only 65 percent of the estimated 

31 
P.31 

boiler population. In addition, the MFBI data contained obvious 

errors that in* validated some of the data and cast doubt on the 

validity of the remaining information. 

An attempt was made to verify the percent distributions for 

each usage by comparing the MFBI based finding with those reported by Stanford Research Institute (Stanford, 1970). The 

basis for the Stanford study differed in that it combined industrial process steam and space heat into one category, and that it 

reported a total for petroleum products. Table 2-21 presents the 

results of the comparison of the two different studies. 

TABLE 2-21. COMPARISON OF FUEL AND USE ESTIMATES 

Fuel 

Coal 

Oil 

Natural 

Gas 

Study 

Stanford study 

Present study 

Stanford study 

Present study 

Stanford study 

Present study 

Electric 

generation 

3.8% 

26.8% 

3.7% 

13.4% 

3.9% 

11.1% 

Process steam and 

space heat 

96.2% 

71.2% 

96.3% 

86.6% 

96.1% 

88.9% 

The fuel usage estimate for generation of electricity, 

derived from MFBI data, is consistently higher than the usage 

estimated by Stanford. The Stanford study does not state how the 

distribution between electric generation and other industrial 

uses was determined, but the similarity between values for different fuels suggests that a single factor was used for all 

fuels. 

Since the MFBI study focused on boilers over 29 MW (100 x 

10 Btu/h), and it is this boiler Capacity category that is 

likely to account for almost all of the electricity generation by 

industrial boilers, applying the MFBI fuel usage distribution to 

the total industrial fuel consumption creates an unrealistically 

high estimate for the percent of fuel being used to generate 

electricity. Adjusting these values to reflect fuel consumption 

by all types and sizes of industrial boilers should yield values 

32 
P.32 

en 10 and 15 percent of consumption of coal for the generation 

iectricity and 5 to 10 percent of consumption for gas and 

No further attempt was made at reconciling the differences 

a on the MFBI generated and Stanford values. There are jjetween 

reicient data to permit calculation of fuel consumption by insutLX 

si nf boiler (needed to determine actual enduse-fuel distribution) and further efforts to reconcile the values are not 

• t-ified in light of the limited utility of such findings. 

The estimates of fuel consumption and capacity permitted the 

offlputation of overall load factors. The results of this computation are shown in Table 2-22. 

TABLE 2-22. ESTIMATED LOAD FACTORS FOR INDUSTRIAL 

AND COMMERCIAL BOILERS BY FUEL 

industria l 

fuel 

Capacity , 

MW therma l 

(10 6 Btu/h ) 

Commercial 

fuel 

Coal 

Residual oi l 

Distillat e oi l 

Gas 

181,60 1 (619,800) 

248,464 (848,000) 

66,27 7 (226,200) 

433,40 6 (1,479,200 ) 

57,92 6 

110,78 3 

61,47 1 

(197,700) 

(378,100) 

(209,800) 

Consumption, 

1015 J 

(1012 Btu) 

1,031. 2 

830. 8 

282. 0 

4,282. 0 

(976.5 ) 

(786.7 ) 

(267.0 ) 

(4,058.8 ) 

Calculate d 

loa d 

facto r 

Total 

169,09 0 (577,100 ) 

1,329,01 9 (4,535,900 ) 

132. 1 (125.2 ) 

1,030. 2 (975.6). 

910. 9 (862.6) 

2,452. 5 (2,322.4 ) 

0.180 

0.106 

0.13 5 

0.31 3 

10,951. 7 (10,374.7 ) 

0.072 

0.29 5 

0.46 9 

0.45 9 

0.26 1 

The figures in some categories are low compared with previous 

estimates, and the weighted average of 26.1 percent is lower than 

the estimate of 35 percent from a previous boiler study (Ehrenfeld 

et al., 1971). Estimates from Battelle (Putnam et al., 1974) are 

in Table 2-23 with the comparable value from the present study. 

33 
P.33 

TABLE 2-23. COMPARISON OF BATTELLE AND PEDCO LOAD FACTORS 

Estimated load factors by fuel 

Pulverized coal and cyclone 

Other coal fired 

Residual oil 

Distillate oil 

Natural gas 

Commercial 

Battelle 

0.424 

0.305 

0.245 

0.206 

0.318 

PEDCo 

0.072 

0.295 

0.469 

0.459 

Industrial 

Battelle 

0.524 

0.426 

0.368 

0.330 

0.518 

PEDCo 

0.180 

0.106 

0.135 

0.313 

The Battelle estimates were derived from data contained in 

the EPA National Emissions Data System (NEDS). These data have 

known limitations (e.g., New York State is not included), and 

contain-some errors. Battelle reported, for example, that for 

some bbilers the reported capacity and fuel consumption produced 

a load: factor greater than 1.0. Thus the Battelle load factors, 

although generally considered as the best available, are not 

based on complete data; differences with them do not necessarily 

diminish the credibility of the data used to derive national 

average load factors for this study. 

Nevertheless the values derived in this study for industrial 

units appear low. This is probably because of assumptions concerning replacement rates. Based upon discussions with boiler 

manufacturers, it was assumed that 27 percent of the sales of 

water-tube and fire-tube boilers and 50 percent of the sales of 

cast iron boilers were replacements. These assumptions directly 

affect the total boiler capacity calculations (e.g., 27 percent 

of the new capacity additions for water-tube boilers replace 

existing units yielding a net increase in capacity of 73 percent 

of the sales). Furthermore, the assumptions do not factor in 

replacement of coal-fired units by new oil- and gas-fired capacity (i.e., if a new oil- or gas-fired unit is purchased to replace a coal-fired unit, no corresponding reduction in the coalfired capacity was incorporated in the study). The sales data 

34 
P.34 

-tube and fire-tube boilers were obtained from ABMA for 

enr water*"1- £° „y. i975, and the data on cast iron boilers were obtained 

1066 through i*'-" 

uvdronics Institute for 1965 through 1975. Sales of 

from

 tn e Hy 

f ed boilers were quite low for the period covered; hence, 

C umed retirement rate was also low. The average boiler age 

_ented in Table 2-24 suggest that the assumption led to data pre»<= 

overestimate *.^m^tes s of existing coal-fired boilers, since the percent 

capacity for coal-fired units is much lower than for other 

of new i- f 

fuelsOn the other hand, the figures may indicate that a substan-

• i number of boilers are on standby. The relatively low load 

etors for boilers firing residual oil may be explained in the 

manner, since sales of water-tube boilers (which are by far 

the largest class) were low in relation to the total number of 

water-tube boilers. The low load factor for boilers firing distillate oil in industrial service and the high load factor for 

those in commercial service suggest that some assumptions made 

about type of service may be invalid. The load factors for gas 

are not unreasonable, except that the factor for industrial 

service was expected to be higher than that for commercial 

service. The use of interruptible gas by industrial concerns may 

be a partial explanation, however, or the ratios presented by 

Battelle and used in this study for industrial versus commercial 

boilers (Putnam et al., 1974) may not be applicable to the present population of boilers. 

Additional work is required to resolve the replacement, 

retirement, and standby issues in order to generate better estimates of capacity; the required information could probably be 

obtained most effectively by canvassing the boiler manufacturers 

and contacting the ABMA. 

Although considerable effort was expended in this study to 

develop good estimates of capacity, the retirement and replacement issue could not be pursued further within the existing study 

constraints. Furthermore, the calculated load factors are not 

used directly in other parts of the study since emission estimates 

35-
P.35 

': f 

•Hi 

in 

il I 4 

If I 

TABLE 

Boiler type 

Water-tube 

Coal 

Residual oil 

•Distillate oil 

Natural gas 

Fire-tube 

Coal 

Residual oil 

Distillate oil 

Natural gas 

Cast iron 

Coal 

Residual oil 

Distillate oil 

Natural gas 

All boilers 

Coal 

Residual oil 

Distillate oil 

Natural gas 

: 2-24. 

170,400 

177,100 

33,000 

220,300 

26,200 

52,700 

34,300 

101,100 

30,500 

30,500 

19,600 

100,500 

227,100 

260,300 

86,900 

421,900 

COMPARISON OF BOILERS 

Boiler 

MW thermal 

Old 

(581,600) 

(604,400) 

(112,500) 

(752,000) 

(89,400) 

(179,800) 

(117,200) 

(345,100) 

(104,200) 

(104,100) 

(66,800) 

(343,000) 

(775,200) 

(888,300) 

(296,500) 

(1,440,100) 

BY AGE 

capacity, 

(106 Btu/h) 

Newa 

9,700 

43,400 

5,700 

86,100 

0 

30,700 

20,200 

37,500 

1,100 

23,300 

14,300 

43,000 

10,800 

97,400 

40,200 

166,600 

(33,100) 

(148,100) 

(19,400) 

(293,800) 

(0) 

(104,800) 

(69,000) 

(127,900) 

(3,600) 

(79,500) 

(48,700) 

(146,800) 

(36,700) 

(332,300) 

(137,100) 

(568,500) 

% New 

5.4 

19.7 

14.7 

28.1 

0 

36.8 

37.1 

27.0 

3.3 

43.3 

42.2 

30.0 

4.5 

27.2 

31.6 

28.3 

New represents capacity added between the years 1967 and 1977 

36 
P.36 

ed on fuel consumption statistics, and further analysis of 

of the past 10 years would not necessarily provide addi1 insight on current and future practice. 

GROWTH PROJECTIONS FOR INDUSTRIAL/COMMERCIAL BOILER. 

2 , 4

 POPULATION 

The major factors affecting the future growth of the indus-

. , /commercial boiler population are the economic growth of the 

tion, technological advancements in energy production and use, 

el use patterns, and energy and environmental regulatory 

trends. Although the projections contained in this section are 

based only on economic growth, the qualitative effect of the 

other factors will be discussed. 

In the industrialized states, State Implementation Plan 

(SIP) requirements for fossil-fuel-fired boilers include regulations governing emissions of particulate matter and sulfur 

dioxide (S02) from industrial boilers. A typical equation based 

on the Illinois SIP for allowable particulate emissions is: 

E = 5.18 Q-°'7 1 5 

where E is allowable particulate emissions in lb/10 Btu 

Q is heat input rate in 106 Btu/h. 

The allowable particulate emission rate ranges from 430 to 

43 ng/J (1.0 to 0.1 lb/106 Btu) as the heat input varies from 2.3 

to 73.25 MW thermal (10 to 250 x 106 Btu/h). 

Regulations governing SO2 emissions vary for each type of 

fuel. For coal firing, SO2 regulations vary from 86 to 2580 ng/J 

(0.2 to 6.0 lb/106 Btu). For fuel oil firing, the regulations 

(normally expressed as a limitation on the sulfur content in the 

fuel) are equivalent to 86 to 344 ng/J (0.2 to 0.8 lb/106 Btu). 

To date no Federal regulations have been promulgated for new 

boiler installations under 73.3 MW thermal (250 x 106 Btu/h) heat 

input, and manufacturers of industrial boilers have not yet had 

to deal extensively with emission limitation problems. The 

37