REDCo ENVIRONMENTAL
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RNAL
COST EQUATIONS
FOR INDUSTRIAL
BOILERS
by
PEDCo Environmental, Inc.
11499 Chester Road
Cincinnati, Ohio 45246
CONTRACT NO. 68-02-3074
Assignment 17 (PN 3400-Q)
Project Officer
John Pratapas
Economic Analysis Branch
U.S. ENVIRONMENTAL PROTECTION AGENCY
RESEARCH TRIANGLE PARK, NORTH CAROLINA 27711
January 1980
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CONTENTS
Page
1. Introduction 1-1
2. Cost Equations 2-1
3. Documentation of Annual Labor Requirements 3-1
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1.0 INTRODUCTION
The purpose of this task was to modify certain bases used
to develop costs and subsequent equations in previous tasks and
to prepare revised costs and cost equations. After the comple-
tion of background work for the U.S. .Environmental Protection
Agency (EPA) in support of New Source Performance Standards for
industrial boilers, PEDCo Environmental, Inc., has developed a
computerized data base system for estimating industrial boiler
costs. This system, known as the Boiler Costing System (BCS),
was developed under a contract with the Department of Energy
(DOE). Boiler costs submitted during the course of the indus-
trial boiler work for EPA have been compared with those obtained
by the use of the BCS, and the original equations developed for
EPA have been revised where appropriate to reflect the BCS
costs. The equations have also been revised to allow for vari-
ous installation scenarios» (in addition to the original single-
boiler, greenfield-installation concept) and to enable esti-
mation of costs for installation of multiple packaged oil-fired
boilers instead of a single, large, field-erected unit.
Section 2 presents modified cost equations for six basic
types of boilers, cost equation modifiers for special installa-
tions, and multipliers for multiple packaged-boiler substi-
tution. Section 3 presents the basic assumptions used to
1-1
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estimate annual labor costs in the BCS program, which are com-
parable to those used in the development of the original costs
for EPA. Two cases are analyzed to delineate workers' activi-
ties and manpower requirements on a per-shift basis.
1-2
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SECTION 2
COST EQUATIONS
2.1 EQUATIONS
The simplified equations for estimating industrial boiler
costs are based on the PEDCo/DOE BCS program and previous work
«
for EPA*. Capital and annual cost equations have been developed
for various types of field-erected and packaged boilers that
fire coal or oil. Equations for all of the field-erected
boilers are based on the BCS program; equations for the packaged
units are based on information contained in the footnoted
report. Cost equations for packaged boilers cannot be developed
from the BCS program because it was not designed to estimate
costs for boilers with a heat input less than 100 x 106 Btu/h.
Capital and annual cost equations are based on an analysis
of the costs of several different sizes of a given boiler type.
Capital costs are divided into three components and a specific
equation has been developed for each component. The capital
cost components are equipment, installation, and indirect costs.
Annual cost equations were originally separated into variable
and nonvariable costs. Because these equations did not allow
for flexibility in labor and operating requirements, the have
* PEDCo Environmental, Inc. Capital and Operating Costs for
Industrial Boilers. Prepared under Contract 68-02-3074
Assignment 7) for U.S. Environmental Protection Agency,
Research Triangle Park, North Carolina. June 1979.
2-1
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been expanded to specify seven individual equations: utilities
and chemicals, ash disposal, direct labor, supervision, main-
tenance, replacement parts, and overhead.
2.2 SPECIAL CASE INSTALLATIONS
Tables 1 through 6 present equations for estimating the
cost of a single greenfield boiler installation, i.e., one in
which the boiler, boiler house, and all auxiliaries are com-
pletely new. The process plant that the new boiler will serve
has no influence on its cost. It should be noted that the
equations are structured on the basis of "best fit" to the
individual data points; therefore, they should not be used
beyond the range of the boiler size indicated.
In two special cases, cost equation modifiers have been
developed to permit cost estimating of field-erected boilers.
The first case (Case C) considers two identical, field-
erected, greenfield boiler installations being constructed
simultaneously, (i.e., a dual unit facility). This effects
capital cost savings through shared equipment, reduced instal-
lation costs, and less indirect costs. Annual operating costs
are likewise reduced because the utilities and manpower require-
ments are shared. Table 7 presents Case C multipliers for
field-erected coal-fired and residual oil-fired boilers. Appli-
cation of the appropriate modifier will enable calculation of
the approximate cost of a dual unit facility.
2-2
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TABLE 1. COST EQUATIONS FOR COAL-FIRED, PACKAGED, WATER-TUBE,
UNDERFEED-STOKER BOILERS
(15 x 106 to 60 x 106 Btu/h)
Capital costs: a'b
p - rjmpr*+-
Installation
T nrii y*of"t /"net c
Annual costs:3'
Utilities and
tiiemi ca i 3
nan disposal
UireCi laDur
Supervi sion
Mai ntenance
Replacement
parts
Overhead
fifi T3? n°*622 /*1»800\ 4 971:7 no-fiifl
53,219 Q°'6S (n'^°0) + 2882 Q0'7.96
dQ IfiR nft>fi*^ /ll.SOO.n. a?K
HU , 1OO y " t ,, J
CF r Q ^ -ll.SOOvn-Qx A ,ft..,
°-6°[CU^xlO-s)Q*3.690xlO^]( H 10"6
shifts x 2190
8760 * •*
*
.shifts x 2190v rq + 5.3 x 10§
1 8760 J L 99.29 - Q J
, shifts x 2190, rQ + 4.955 x 106 .
1 8760 ; L 99.23 - Q J
U7nt: v -ink r, - i a^a v ^nP^*s fiii^P-P^i • 002*
»• ' • H
0.3(direct labor) + 0.26(all labor and replacement parts)
a
Costs in June 1978 dollars.
Q - heat input rate, 106 Btu/h.
H = heating value of coal, Btu/lb.
CF = boiler capacity factor, decimal.
A = ash content of coal, %.
Does not include fuel costs.
2-3
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TABLE 2. COST EQUATIONS FOR COAL-FIRED, FIELD-ERECTED, WATER-TUBE,
SPREADER STOKER BOILERS
(75 x 106 to 250 x 106 Btu/h)
Capital cost:a'b
Equipment
Installation
Indirect costs
Annual cost:3'
Utilities and
chemicals
Ash disposal
Direct labor
Supervision
Maintenance
Replacement
parts
Overhead
f Q \/Hv"ft.as
"(7.5963 x 10~8 Q) + 4.7611 x uf5/vll,800'
/ Q ' \/H»-o.as
"(8.9174 x 10"8 Q) + 5.5891 x in"*'"11'800'
/ Q \f H » -n-as
v - - 'Ml ftflfl'
(1.2739 x 10 7 Q) + 7.9845 x 10 5 il»BUU
CF (29,303 + 719.8 Q)
CF [(547,320 + 66,038 In ^)(j|p)°'9754] (0.36)
fshifts x 2190 ,f«Q« D« 5 ... Q9>
8760 ;^£Ui,ot'o • a.jDo v )
.shifts x 2190 W13C OOQ,
C 8760 JUJo.JOo;
, shifts x 2190v.--07 Of). n «-. 0?v
50,000 + 1000 Q
0.3 (direct labor) + 0.26 (all labor and replacement parts)
Costs in June 1978 dollars.
Q = heat input, 106 Btu/h.
H ~ heating value of coal, Btu/lb.
CF = capacity factor, decimal.
A = ash content of coal, %.
Does not include fuel costs.
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TABLE 3. COST EQUATIONS FOR FIELD-ERECTED, WATER-TUBE
PULVERIZED COAL-FIRED BOILERS
(200 x 106 to 700 x 106 Btu/h)
Capital costs:a>b
Equipment
Installation
Indirect costs
.a,b
Annual costs:
Utilities and
chemicals
Ash disposal
Direct labor
Supervision
Maintenance
Replacement
parts
Overhead
[4,926,066 - 0.00337 H2]
1,547,622.7 + 6740.026 Q - 0.0024133 H2
1,257,434.72 + 6271.316 Q - 0.00185721 H2
CF (189,430 + 1476.7 Q)
CF[(-641.08
Q)
>985 . 20,636,709,
219°
K-ltl62.910 + 256,604 In Q)
(180,429 + 405.4 Q)
0.3 (direct labor) + 0.26(all labor and replacement parts)
Costs in June 1978 dollars.
b Q = heat input, 106 Btu/h.
H = heating value of coal, Btu/lb.
CF = capacity factor, decimal.
A = ash content of coal, %.
c Does not include fuel costs.
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TABLE 4. COST EQUATIONS FOR PACKAGED FIRE-TUBE BOILERS
(5 x 106 to 29 x 106 Btu/h)
Capital costs:3'
Equipment
Installation
Indirect costs
Residual
17,360 Qc
4324 Q +
2317 Q +
Fuel type
oil Distillate oil or natural
>• SS7
56177
29749 ,
15,981 QO'561
4261 Q + 56041
2256 Q + 28649
gas
Annual costs (all fuel types):3'
Utilities and
chemicals
Direct labor
Supervision
Maintenance
Replacement
parts
Overhead
CF
„*£ (580 Q
3900)
2190
} (105)30n)
2190
> -f Q>
(160° Q * 8000)' 1f
15
2190
(708.7 Q + 4424)
0.3 (direct labor) + 0.26 (all labor & replacement parts)
Costs in June 1978 dollars.
Q = heat input, 106 Btu/h.
CF = capacity factor, decimal.
Does not include fuel costs.
2-6
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TABLE 5. COST EQUATIONS FOR PACKAGED, WATER-TUBE BOILERS FIRING
(30 x 106 to 150 x 106 Btu/h)
.a,b
Capital costs:
Equipment
Installation
Indirect
Annual cost:3'
Utilities and
chemicals
Direct labor
Supervision
Maintenance
Replacement
parts
^
Overhead
OteMlktt 0
15,925 QO-77S
54,833 QO-364
16,561 g
°*
(202 Q + 24,262)
shifts x 2190
8760
) C-
Q2
-_]
(8.135 x 10 « Q - 1.585 x 10 2)
shifts x 2190.
8760
fl|M7,000 + 77,190)
7185
0.3 (direct labor) + 0.26 (all labor and replacement parts)
Costs in June 1978 dollars.
Q = heat input, 106 Btu/h.
CF = capacity factor, decimal.
Does not include fuel costs.
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TABLE 6. COST EQUATIONS FOR FIELD-ERECTED, WATER-TUBE BOILERS
FIRING RESIDUAL OIL/NATURAL GAS
(200 x 106 to 700 x 106 Btu/h)
Capital costs: a'b
Equipment
Installation
Indirect costs
3'
Annual costs:
Utilities and
chemicals
Direct labor
Supervision
Maintenance
Replacement
parts
Overhead.
1,024,258 + 8458 Q
579,895 + 5636 Q
515,189 + 4524 Q
CF (43,671.7 + 479.6 Q)
(173'197 * 734
shifts x 2190.
- 8760 - '
9,n
,250
3.094 x 107
<32'029 + 320'4
(50,000 + 250 Q)
0.3 (direct^ labor) + 0.26 (all labor and replacement parts)
Costs in June 1978 dollars.
Q = heat input, 106 Btu/h.
CF = capacity factor, decimal.
Does not include fuel costs.
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TABLE 7. CASE C MULTIPLIERS FOR DETERMINING THE COST OF A DUAL-UNIT
FACILITY FOR FIELD-ERECTED COAL-FIRED AND RESIDUAL OIL-FIRED BOILERS3
Cost equation
Multiplier
Coal-fired boilers:
Equipment and installation
Indirect costs
Utilities, chemicals, and ash disposal
All labor, replacement parts, and overhead
Residual oil-fired boilers:
Equipment and installation
Indirect costs
Utilities and chemicals
All labor, replacement parts, and overhead
0.874
0.628
0.848
0.767
0.934
0.672
0.845
0.799
a The estimated cost for one of these boilers is determined by modifying
the cost equations for a single boiler.
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The other special case (Case E)considers the installation
of a single new field-erected boiler at an existing steam plant.
Existing auxiliary equipment, fuel handling and storage systems,
buildings, and waste treatment systems can often be shared or
modified to permit use by an additional new boiler. Installa-
tion and indirect costs are also less than for a single-unit
greenfield installation. Reduced annual operating requirements
result from the use of a common manpower pool. Equipment and
system sharing reduces the cost of replacement parts. Table 8
presents Case E multipliers for field-erected coal-fired and
residual oil-fired boilers. The approximate capital and annual
operating costs for installation of a boiler at an existing
facility can be determined.
2.3 MULTIPLE PACKAGED WATER-TUBE BOILERS THAT FIRE RESIDUAL OIL/
NATURAL GAS
PEDCo investigated the cost of installing multiple pack-
aged, water-tube boilers that fire residual oil/natural gas
instead of a single field-erected unit. Multipliers were devel-
oped to estimate the cost of multiple packaged residual oil/
natural gas boilers, based on the cost of one unit and the
i
number of units required to equal the capacity of one field-
erected unit. Determination of the annual costs for the multiple-
packaged-unit installation entails the use of the same equations
as those used to calculate the annual costs of a field-erected
unit of equivalent capacity. The Case C and Case E multipliers
applicable to field-erected annual costs also apply to multiple
packaged water-tube boilers that fire residual oil/natural gas.
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TABLE 8. CASE E MULTIPLIERS FOR DETERMINING THE COST OF A NEW FIELD-ERECTED
COAL-FIRED OR OIL-FIRED BOILER BEING ADDED TO AN EXISTING STEAM PLANT
Cost equation
Multiplier
Coal-fired boilers:
Equipment and installation
Indirect costs
Utilities, chemicals, and ash disposal
All labor, replacement parts, and overhead
Residual oil-fired boilers:
Equipment and installation
Indirect costs
Utilities and chemicals
All labor, replacement parts, and overhead
0.835
0.602
1
0.539
0.937
0.674
1
0.536
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The following multipliers are used to estimate the costs of
multiple packaged residual oil/gas boilers to replace one equiva-
lent capacity field-erected, residual oil/gas boiler. The
capital cost multipliers are applied to the cost of a single
package unit.
Equipment and installation cost multiplier:
M! = 0.76n + 0.263, where
Mj = multiplier for equipment and installation
equations
n = number of packaged units
Indirect cost multiplier:
M2 = 0.551n + 0.181, where
M2 = multiplier for indirect costs
n = number of packaged units
Based on the equations shown above, Table 9 shows an example
case of cost calculations for the installation of multiple
packaged boilers to replace a single field-erected boiler.
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TABLE 9. CAPITAL COSTS OF INSTALLING MULTIPLE PACKAGED
OIL-FIRED UNITS INSTEAD OF A SINGLE FIELD-ERECTED UNIT*
One packaged unit
(100 x 106 Btu/h)
Equipment $ 565,000
Installation 293,100
Subtotal 858,100
Indirect
costs 278,700
Total $1,136,800
four packaged units
[4 x (100 x 106 Btu/h)]
Mj = 3.303 $1,866,200
Mj = 3.303 968,100
2,834,300
M2 = 2.385 664,700
$3,499,000
per unit $ 874,800
One field-erected unit
(400 x 106 Btu/h)
$4,407,500
2,834,300
7,241,800
2,324,800
$9,566,600
Four 100 x 106 Btu/h packaged boilers instead of one 400 x 106 Btu
field-erected boiler.
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SECTION 3
DOCUMENTATION OF ANNUAL LABOR REQUIREMENTS
The labor requirements reflected in the cost equations for
field-erected boilers (Section 2) are based on the PEDCo/DOE BCS
program, whereas manpower requirements for packaged boilers
reflect information contained in PEDCo.'.s June 1979 report (foot-
noted in Section 2).
Modern power plant design practice mandates the use of
high-efficiency boilers, burners, heat exchangers, and any
justifiable heat reclaim systems. Included are such items as
economizers, blow-down heat exchangers, low excess-air controls,
combustion and flue gas monitors, special high-efficiency bur-
ners, larger condensate return systems, and increased insul-
ation. All of these require direct and maintenance labor for
their continued, reliable operation.
The operation and maintenance (O&M) costs developed by
PEDCo are based largely on the practices observed during plant
inspections of utility plants and more than 50 major fuel
burning installations (MFBI's) across the nation. During these
inspections we frequently discussed operating and maintenance
costs with plant supervisors. Visual inspections of the general
condition of the facility (boiler, auxiliaries and control
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equipment) indicated a generally poor maintenance level on
existing MFBI equipment. Among the items noted were inoperable
or marginally operable equipment, steam and condensate leaks,
deteriorated insulation, instrumentation that was obviously out
of calibration, as high as 150 percent excessive air levels,
uninsulated steam and condensate lines, condensate being sent
directly to the drain, and so on.
Some plants, however, were exemplary in their operational
and maintenance procedures, and costs at these plants serve as
the basis for PEDCo O&M costs. We believe that a new boiler
plant today would be better maintained and operated than most of
the existing plants. The economic importance of efficient
operation and scheduled maintenance cannot be overstated con-
sidering the price of fuel and the increasing regulatory pres,-
sures for clean operation. Although this basis for O&M costing
may represent only the top 10 percent of existing boiler facili-
ties, it would certainly be in error to base costs on the low or
even the average O&M costs documented by many facilities today.
Table 10 lists the annual manpower requirements developed
by PEDCo for the six basic boiler types at various capacities.
»
Requirements are based on operating 24 hours per day, 7 days per
week. The labor force is established on an annual average and
is not discounted for a unit's capacity factor. If the boiler
is shut down for extended periods or on weekends and personnel
can be reassigned to other jobs, the labor force can, of course,
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TABLE 10. ANNUAL MANPOWER REQUIREMENTS FOR SELECTED
BOILER SIZES BY TYPE
Heat input, 106 Btu/h
Direct labor
Supervision
Maintenance
Heat input, 106 Btu/h
Direct labor
Supervision
Maintenance
Heat input, 106 Btu/h
Direct labor
Supervision
Maintenance
Heat input, 106 Btu/h
Direct labor
Supervision
Maintenance
Heat input, 106 Btu/h
Direct labor
Supervision
Maintenance
Heat input, 106 Btu/h
Direct labor
Supervision
Maintenance
Field-erected oil /gas units
200
12
3
3
400
18
4
5
500
20
4
6
600
23
4
7
700
26
4
8
Field-erected stoker units
75
9
4
3
100
10
4
4
150
13
4
4
200
17
4
6
250
20
4
8
Field-erected pulverized coal units
200
18
4
6
400
27
6
12
500
31
6
16
600
36
6
16
700
40
6
16
Packaged stoker units
15 30
5 6
2 2
2 2
60
7
4
4
Packaged oil /gas units
30
4
2
1
60
4
2
2
100
6
2
2
150
8
2
2
Packaged firetube oil/gas units
5
4
.5
15
4
2
1
29
4
2
1
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be adjusted accordingly. If, however, the load factor is low
simply because the boiler is not fired at capacity, the manpower
requirements are not reduced.
It must be emphasized that the labor requirements reflect a
new boiler in a single-unit powerhouse. If a boiler were being
installed into an existing powerhouse, the labor requirements
could be significantly reduced. Previous analysis of costs for
such an installation (Case E) reveals that the assumed labor
force of the existing powerplant could be utilized (to some
extent) to operate and maintain the new boiler. The analysis
showed that such usage of labor would mean that the requirement
for an incremental labor force (for the new boiler) would be
about half that for a new boiler in an individual powerhouse.
The per shift breakdowns of job functions for this Case E
scenario become essentially half the allotments described pre-
viously.
A breakdown of the different duties performed by the labor
force is included to support the labor requirements developed by
PEDCo. Two cases are examined in detail: a field-erected,
pulverized-coal-fired (PC) boiler with a heat input capacity of
400 x 10s Btu/h, and a field-erected, spreader stoker boiler
with a heat input capacity of 200 x 106 Btu/h.
The PC boiler would require labor for the coal thawing/
unloading operations, coal pile/reclaim operations, pulverizers/
feeders, the boiler itself (operators, feedwater treatment
system, and steam/condensate return systems), bottom ash/fly ash
systems, and other auxiliary items.
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On an average per-shift basis, 6.75 men are involved in the
direct labor functions of the PC unit. Two and three-fourths
men per shift are assigned to the coal unloading, reclaim, and
in-plant storage activities. These areas include the thawing
operation, coal pile movement and reclaim, and monitoring of the
movement of coal into the bunkers by conveyors. They may also
have to monitor the feeders and pulverizer operation. Two men
per shift are assigned to boiler operation, which includes
altering boiler fuel and air feed rates at required load levels,
•' <
operating the burner and pulverizer, steam temperature/pressure,
. i
sequencing soot blowers, logging boiler operations, and per-
forming other associated functions. Two men are assigned to the
operation of the ash handling system. They must periodically
monitor the removal of bottom ash to the silo storage, as well
as the clinker breaker, pneumatic system/ and silo dust sup-
pression systems. They also must perform such auxiliary func-
tions such as monitoring feedwater treatment, deaerator, conden-
sate, and makeup water operations.
It is somewhat inaccurate to "assign" these laborers to any
given jobs. The coal feed and ash handling system manpower may
rotate duties or incorporate their efforts to solve any given
operational problem in this area at any given time.
On a PC boiler with a capacity of 400 x 106 Btu/h, for
example, the per-shift breakdown for four shifts may be more
realistically shown below:
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Shift
1
2
3
4 (swing)
Coal handling
5
2
2
2
Boiler crew
2
2
2
2
Ash/Auxiliary
2
2
2
2
This manpower arrangement accounts for unloading the coal during
the first shift. This breakdown is again an annual average
configuration; coal is not usually unloaded daily (once a week
is more likely). On larger PC units (e.g., 700 x 106 Btu/h) the
coal unloading operations will most probably require more man-
power usage on the first two shifts to, handle the coal quanti-
ties of the boiler.
The direct labor manpower requirements for a field-erected,
spreader stoker boiler with a capacity of 200 x 106 Btu/h are
functionally similar to those for the pulverized coal-fired
boiler just discussed, except that the manpower level is re-
duced to one coal handler, one boiler operator, and two and
one-fourth ash handler/auxiliary system operators. In this
per-shift breakdown two men will probably be required for cer-
tain coal handling functions (for safety reasons), and the
assignment of specific duties becomes more difficult to iden-
tify. The operation of the stoker .itself takes the place (to
some extent) of pulverizer operation in the previous example.
Supervision and maintenance labor for the two cases are as
follows:
Supervisors
Mai ntenance
Field-erectd PC stoker
(400 x 106 Btu/h)
6
12
Field-erected stoker
(200 x 106 Btu/h)
4
6
3-6
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On an average per-shift basis, this amounts to 1.5 supervisors
for the PC unit and 1 for the spreader stoker boiler. At least
one person is required per shift to be in responsible charge of
operations at coal-fired units. An average of 1.5 supervisors
per shift is used for all of the large PC units, realistically
representing two supervisors each for the first and second
shifts and one each on the third and fourth shifts.
Maintenance labor is that labor which is utilized to pro-
vide reliable, safe operation of the boiler, coal handling, and
other auxiliary systems. It is assumed that a high level of
maintenance will be performed during scheduled boiler outages.
The average annual maintenance manpower requirements listed in
Table 10 reflect these occasionally high maintenance levels.
On an annual per-shift basis realistic utilization of
maintenance labor would be concentrated into the first two
shifts. For example, in a PC unit with a capacity of 400 x 106
Btu/h the breakdown would be 4, 4, 2, and 2 for the four shifts,
respectively, which would allow the required coal handling
system maintenance and most of the scheduled maintenance to be
conducted during daylight hours. This approach also allows for
procurement of parts during normal business hours, and makes
available a concentration of maintenance labor during the first
shift, concurrent with coal handling operations (which typically
include high-maintenance items).
In summary, the PEDCo estimates include a labor schedule
with sufficient manpower to perform more than a minimal level of
3-7
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maintenance. The application of this schedule in many existing
plants would significantly reduce operating problems and thereby
increase productivity and profitability. Also worthy of serious
consideration is the conservation of energy to be realized.
Although increased routine maintenance and modern boiler opera-
ting practices, such as flue gas and combustion monitoring,
increase manpower requirements above typical historic levels,
such practices also promote efficient fuel usage. This is in
addition to the energy saving subsystems and components incor-
porated in the new boiler designs.
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