United States EPA-600 /8-84~016
Environmental Protection
Agency May 1984
v>EPA Research and
Development
COST AND PERFORMANCE MODELS
FOR ELECTROSTATICALLY
STIMULATED FABRIC FILTRATION
Prepared for
Office of Air Quality Planning and Standards
Prepared by
Industrial Environmental Research
Laboratory
Research Triangle Park NC 27711
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EPA-600/8-84-016
May 1984
COST AND PERFORMANCE MODELS
FOR ELECTROSTATICALLY
STIMULATED FABRIC FILTRATION
by
Andrew S. Viner and Bruce R. Locke
Research Triangle Institute
P.O. Box 12194
Research Triangle Park, North Carolina 27709
EPA Contract No. 68-02-3170
Task No. 76
EPA Project Officer: William B. Kuykendal
Particulate Technology Branch
Industrial Environmental Research Laboratory
Research Triangle Park, North Carolina 27711
U. S. Navy Project Officer:
Naval Surface Weapons
U.S. Navy
Dahlgren, Virginia 22448
Donald Rowe
Center
prepared for
U.S. Environmental Protection Agency
Office of Research and Development
Washington, D.C. 20460
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ABSTRACT
A survey of the literature on performance models for pulse-cleaned
fabric filters is presented. Each performance model is evaluated for its
ability to predict average pressure drop from pilot plant data. The best
model is chosen and used in conjunction with pressure drop reduction data
from an electrostatically stimulated fabric filter (ESFF) pilot plant to
produce a model of ESFF performance. The accuracy of the performance
models is limited by their primitive nature and the size of the pulse-jet
performance data base. For those cases where the baghouse, dust, and
fabric to be modeled are very similar to the pilot plant from which the
model was developed, the model should perform adequately for comparison
between ESFF and non-ESFF baghouses.
Published correlations relating equipment size and cost are used in a
model for predicting the capital and operating costs of conventional pulse-
jet baghouses. A comparison between predicted capital costs and independently
obtained estimates shows that the baghouse cost model is capable of ±20%
accuracy. A prototype design for ESFF hardware is developed and cost
quotes obtained from vendors are incorporated into a predictive equation
for ESFF costs. In view of the fact that there are no existing pulse-jet
ESFF baghouses, the prototype design is subject to revision. This lack of
certainty in the hardware design restricts the accuracy of ESFF cost predic-
tions to ±30. The cost model is best used in comparing cost estimates of
ESFF and non-ESFF pulse-jet baghouses and in comparisons of different sizes
of conventional pulse-jet baghouses.
The performance and cost models are incorporated into a computer
program for two different computers: the Tektronix series 4050 computers
and the TRS-80 Model I and III microcomputers. The program requires pulse-
jet design data as input and predicts average pressure drop, capital cost,
operating cost, and net present value. Complete program documentation is
also included.
11
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TABLE OF CONTENTS
Chapter Page
Abstract ii
Figures iv
Tables v
Abbreviations and Symbols vi
Acknowledgments ix
1 SUMMARY 1-1
1.1 Introduction 1-1
1.2 Conclusions 1-1
1.3 Recommendations 1-2
2 PERFORMANCE MODEL 2-1
3 ECONOMIC ANALYSIS AND MEASURES OF MERIT 3-1
3.1 Calculation of Savings/Investment Ratio 3-3
3.2 Calculation of Payback Period 3-4
3.3 Calculation of Net Present Value 3-5
4 PULSE-JET BAGHOUSE COST ESTIMATION 4-1
4.1 Introduction 4-1
4.2 Capital Equipment 4-8
4.3 ESFF Hardware 4-10
4.4 Operating and Maintenance Costs 4-14
4.5 Annual Capital Cost 4-18
4.6 Example Calculations 4-19
4.7 Accuracy of Capital Cost Predictions 4-24
5 COMPUTER PROGRAM 5-1
5.1 System Requirements 5-1
5.2 Background Information 5-2
5.3 Sample Session of PULSEJET Execution 5-4
6 REFERENCES 6-1
APPENDIX A: Conventional Pulse-Jet Models A-l
APPENDIX B: PULSEJET Program Listing B-l
APPENDIX C: Cost Estimates for Industrial Coal-Fired
Boiler Pulse-Jet Baghouse Systems C-l
111
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FIGURES
No.
2-1 Pressure drop versus cycle time for pulse-jet fabric
filters 2"3
2-2 PDR versus applied field for data from VanOsdell et al. . 2-7
4-1 Assumed ESFF prototype 4-11
5-1 Program flowchart 5-3
5-2 At the beginning of the PULSEJET program, a heading is
printed and then there is a pause while some variables
are initialized. The date is the first item requested.
It can be entered in any format. 5-5
5-3 The Main Menu of the PULSEJET program presents
the user with 8 options 5-6
5-4 A brief description of how to run the program
is printed on the screen when the operator
chooses the HELP option 5-8
5-5a Plant data menu showing default values for
each parameter (Tektronix version) 5-9
5-5b In the TRS-80 version of the program the plant
data menu is divided into two "pages" 5-10
5-6 A value is changed by specifying the corresponding
item number (1-21). The program prints the
current value and asks the user for the new value 5-11
5-7 Input menu for the PULSEJET performance model 5-13
5-8 The program will compute K2 based on AP and AP
(units of K2 are in. H20 ft min/lb). . T ... ma? . . . . 5-15
5-9 Input menu for baghouse design, operating,
and cost data 5-16
5-10 The PULSEJET program prints a list of capital
cost items, operating cost items, and net
present value for new baghouses 5-18
5-11 The printout for a retrofit cost analysis includes
the capital cost of ESFF hardware, the annual
savings in operating cost, the savings/investment
ratio, and the payback period 5-20
5-12 The cost adjustment factors can be changed to reflect the
complexity or simplicity of equipment installation .... 5-21
iv
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TABLES
No. Page
2-1 Performance Model 2-9
4-1 Estimation of Capital Costs 4-3
4-2 Cost Adjustment Factors 4-4
4-3 Annual Operating Expenses 4-7
4-4 ESFF Hardware Costs 4-15
4-5 Design and Operating Parameters for the Example
Calculations 4-20
4-6 Comparison Between Predicted Values and Vendor
Quotes 4-26
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ABBREVIATIONS AND SYMBOLS
ABBREVIATIONS
A. cross-sectional area of pulse-jet nozzle
J
A net cloth area for flow
n
A uniform annual payment
b cumulative uniform series factor
n
C- dust concentration at inlet to filter
i n
CTash annual cost of electricity for ash conveying
CT. capital cost of pulse-jet baghouse
CT capital cost of ash conveyor
CT, capital cost of inlet/outlet dampers
CT, t capital cost of ducting
CTf . unit cost of fabric
CTfan annual cost of electricity for induced draft fan
CTfms capital cost of fan, motor, and starter
CT-jns capital cost of baghouse insulation
CTkWh unit cost of electricity
CTm/m annual cost of maintenance, labor, and materials
CTg^ annual cost of operating labor
CTpond capital cost of ash pond
CTpulse annual cost of electricity for compressed air
CT annual cost of bag replacement
ESFF electrostatic stimulation of fabric filtration
f electric field applied to filter
VI
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ABBREVIATIONS AND SYMBOLS (continued)
ABBREVIATIONS
Fundamental Planning Analysis
I capital investment
K proportionality constant in Darcy's law
KI, K3, K4 constants used in the Leith and Ellenbecker model
K2 specific resistance coefficient based on P
K£ specific resistance coefficient based on P
L length of filter bed
LC length of ash conveyor
mlr maintenance labor rate
NPV net present value
n number of years over which annual payments are made
N number of bags in the baghouse
OHF fractional cost increment for overhead
olr operating labor rate
P pressure drop across filter
P effective residual pressure drop
P. pulse-air reservoir pressure
J
P_,v maximum pressure drop across filter
IIIclX
P actual residual pressure drop
P maximum static pressure
PDR pressure drop ratio
PR reverse pressure drop
AP . average pressure drop across filter
3 V G
Q flue gas flow rate
Vll
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ABBREVIATIONS AND SYMBOLS (continued)
ABBREVIATIONS
R
r
S
Se
Sr
SIR
SPV
t
T
TR
V
W
SYMBOLS
a
P
e
P
effective annual discount rate
fractional reduction in residual pressure drop
drag across filter
effective residual drag across filter
actual residual drag across filter
savings/investment ratio
present value of annual cost savings
time since cleaning of filter
temperature
transformer-recti fi er
air velocity
area! dust loading on filter
fraction of dust removed from filter during cleaning pulse
fraction of that dust removed from filter, a, during the
cleaning pulse that falls to hopper and is removed from
the system
fraction of inlet dust removed from system per cycle
bulk gas density
Vlll
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ACKNOWLEDGEMENTS
This project was funded by the U.S. Environmental Protec-
tion Agency and the U.S. Naval Surface Weapons Center through
an interagency agreement.
The authors would like to acknowledge the guidance and
assistance provided by the EPA Project Officer, Bill
Kuykendal, and by the U.S. Navy Project Officer, Don
Rowe.
IX
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CHAPTER 1
SUMMARY
1.1 INTRODUCTION
Electrostatic stimulation of fabric filtration (ESFF) is the technique
of applying an electric field to the surface of a fabric filter to enhance
the collection of particulate matter. An added benefit of ESFF is a reduc-
tion of the pressure drop across the filter. This technology has been
successfully demonstrated on a pilot scale pulse-jet fabric filter by
VanOsdell et al.1 They have shown from preliminary estimates that this
technology may also be economically feasible.1 This report documents a
computer program that can be used to evaluate the costs of both conventional
and electrically enhanced, pulse-jet, baghouse filters to aid in deciding
when to apply this new technology. The computer program contains modules
that will model the performance and the cost-estimating aspects for the
pulse-jet filter. Descriptions of these modules, a listing of the computer
program, and user documentation are included in this report.
Chapter 2 discusses the pulse-jet performance model including descrip-
tions of the ESFF data found by VanOsdell et al.x Current models available
in the literature for conventional pulse-jet filters are presented in
Appendix A. Chapter 3 details the economic measures of merit that are
applied both to new units and to old units that are retrofitted with new
equipment. Chapter 4 details the equations used to estimate the capital
and operating costs of pulse-jet baghouses with and without ESFF hardware.
The final chapter of the report gives instructions for using the computer
program (listed in Appendix B) to calculate the performance and costs.
1.2 CONCLUSIONS
Performance models for conventional as well as electrostatically
stimulated fabric filtration in pulse-jet cleaned fabric filters have not
been rigorously developed or tested. A simplified model based on user
input of key parameters for the conventional pulse-jet system and on key
1-1
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parameters from the ESFF study of VanOsdell et al.i has been developed in
order to give a rough prediction of the pulse-jet performance.
A model for predicting the capital and operating costs of pulse-jet
baghouses with and without ESFF enhancement has been developed. The model
predicts the cost of the major equipment items based on net cloth area and
gas flow rate. The installation costs and associated indirect costs are
calculated using Lang factors. Based on a comparison with independently
developed cost estimates, the model appears to be capable of predicting
capital costs with ±20 percent accuracy. Based on what is known about the
equipment design and operational requirements, it is expected that predic-
tions of ESFF hardware costs and operation and maintenance costs should
have an accuracy of ±30%.
1.3 RECOMMENDATIONS
Models such as those suggested in Appendix A for conventional
(i.e., non-ESFF) pulse-jet baghouses should be developed further.
The effects of cleaning characteristics, such as maximum static
pressure in the bag and the pressure rise time on baghouse pressure
drop, should be investigated. Further understanding of the
conventional pulse jet, especially with regard to residual dust
loading, should facilitate understanding of the ESFF effect.
Further investigation of the ESFF effect is needed. The effects
of different types of fly ash, fabrics, and variations in applied
voltage on baghouse pressure drop need to be investigated.
The accuracy of all capital and operating cost modeling equations
should be verified by comparison with costs from an operating
baghouse.
The assumed prototype for ESFF hardware needs further development.
When actual design data become available, the cost model should
be modified to reflect the updated design. When cost data from
an ESFF baghouse become available, the cost modeling equation
should be verified.
1-2
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CHAPTER 2
PERFORMANCE MODEL
Design of a pulse-jet fabric filter requires predicting the maximum
and average pressure drops for the filter and for the gas flow through the
entire system, and determining the maximum penetration of particles and
agglomerates through the filter. Prediction of the cost of a fabric filter
is usually more sensitive to the pressure drop calculations since the
collection efficiency is generally greater than 99 percent.2 3 Thus for
the performance model in this cost analysis only the pressure drop will be
considered.
The state of the theoretical and empirical models for predicting
pressure drops in conventional pulse-jet fabric filters is not well devel-
oped. The empirical models are limited to the conditions under which they
were developed. The theoretical, or quasitheoretical, models have not been
well tested for conditions other than those used by their authors; further-
more, they require some data for determining unknown constants. Thus it is
necessary to rely primarily on full-scale plant and pilot-plant experience
for designing new systems.
The approach currently used for modeling electrostatically enhanced
fabric filters requires knowledge of the conventional, nonenhanced filters
and of the effect of the electric field on the ratio of the pressure drop
of the ESFF to that of the conventional filter.1 3 4 Current ESFF research
has not led to other quantitative methods for predicting pressure drop
improvements due to ESFF. At present, the ESFF concept has not been tested
on a large scale (i.e., on the order of 3,000 m3/min). Of the pilot-plant
studies reported in the literature, that of VanOsdell et al.1 is the most
applicable for this study since the pilot unit was operated continuously
over long periods of time using a slip stream from an industrial boiler.
2-1
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Therefore, the pressure drop performance model used in this cost
analysis will rely on user experience for the conventional pulse-jet data
and on the operating experience of VanOsdell et al.l for the ESFF data.
This section describes the performance model and explains why this approach
was used.
Fabric filtration theory has been reviewed by Billings and Wilder.5
The major assumptions used for modeling fabric filters will be presented
briefly to describe the approach taken in the ESFF performance analysis.
Conventional fabric filtration theory is based on the Darcy's law
assumption that the pressure drop across a packed bed of solids is propor-
tional to the velocity and bed length for viscous flow at low Reynolds
numbers. One form of Darcy's law is thus
P = KVL (1)
where P = pressure drop across the bed
L = bed length or dust thickness
K = constant—dependent on bed structure and fluid properties
V = velocity.
For fabric filtration, the experimental data are usually gathered as
pressure drop versus time curves as shown in Figure 2-1. For fabric filters,
in contrast to deep bed filters or packed beds, the length of the bed
changes as the dust is deposited on the fabric surface; therefore, the
pressure drop must be related to the cake buildup on the fabric. It is
assumed that during a given unit of time a constant amount of dust is
deposited on the filter and that the structure of this dust deposit does
not change as more dust is deposited. Thus the surface loading W, mass/area,
increases linearly as the dust thickness increases. Thus from Equation 1
P = K2VW (2)
where W = C-n Vt; the loading on the filter, W, equals the inlet dust
concentration, C^ (mass/volume), that has entered in time, t, with velocity
V. K2 is the specific dust-fabric filter resistance coefficient.
However, the pressure drop across the filter is not strictly a linear
function of time and thus the effect of cleaning needs to be considered in
Equation 2. Figure 2-1 shows that a well-conditioned fabric operating at
2-2
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IV)
I
CO
max
AR
t(W0 = C,nVt)
Figure 2-1. Pressure drop versus cycle time for pulse-jet fabric filters.
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steady state has a residual pressure drop, Pf, caused by the dust that is
not cleaned from the fabric. The nonlinear behavior is not predicted by
Equation 2, and it is often assumed for fabric filters that the behavior
can be described in terms of an effective residual pressure drop, PQ, the
intercept of the curve of pressure as a function of time as shown in Figure
2-1. This equation is
p = P + K2VW . (3)
In order to remove the effect of face velocity, it is often useful to
define the drag as S = P/V. This gives
S = S + K2W . (4)
e
Billings5 notes that S is some function of $r (= Pr/V), the fabric, and
the dust type.
Thus, in order to design a conventional fabric filter for a given set
of inlet conditions, including inlet dust concentration, velocity, and
cycle time, either (1) P (S ) and K2 or (2) P (S ) and the nonlinear
behavior of P (S) with loading must be predicted. Current pulse-jet theories
will be discussed briefly in Appendix A to illustrate the problems with the
available correlations for predicting these parameters. Since there are no
good theories for predicting these parameters, the computer program will
require the input of values of these parameters.
To extend the conventional pulse-jet to the ESFF pulse-jet, one must
predict the change in these parameters with the applied field. Since there
are little data available to predict these effects, rough approximations
must be made based on the available data.
Experimental data from ESFF units are reported in terms of the pressure
drop ratio (PDR) defined as
PDR = (Pmax - VESFF/(Pmax ' ^conventional (5)
Where ?max is the maximum pressure (see Figure 2-1) that is reached in one
cycle of filtration. If PDR is known as a function of applied voltage and
2-4
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(pmax - Pr) conventional is known, then (P - pr)ESFF can be calculated.
To find (Pmax)ESFF the (Pr)ES(_F must be known.
Pilot plant experience indicates that P varies with time as the
r
fabric is conditioned during startup and in the final phase as the bag is
worn out. No attempt is made to account for this; steady state is assumed.
It is also expected that P and therefore P are functions of the cleaning
intensity. No attempt has been made in the literature to predict P as a
function of cleaning efficiency or other operating parameters, but Dennis
and Klemm6 and Dennis et al.7 attempt to predict P as a function of the
reservoir pressure of the cleaning pulse and several other operating parame-
ters. Their work was with coal fly ash filtered with wool and polyester
felts. It was tested on a very limited amount of data, and thus it is not
recommended until further experimental work confirms their findings.
VanOsdell et al. x found that ?r is significantly affected by the ESFF,
but they reported no clear trends or correlations with applied field voltage,
face velocity, or cleaning cycle duration because of scatter in their data
and limited parameter testing. They found an average reduction in residual
pressure drop of 0.42 with a standard deviation of 0.27 for a wide range of
operating conditions. The reduction in residual pressure drop is defined
as
r = (P conventional - P ESFF)/P conventional . (6)
For want of further information, the model for this program shall use a
reduction in residual pressure drop of 0.42 when comparing the ESFF to the
conventional pulse jet. Thus given r and (pr)convent1onal» then (Pr)ESFp
can be predicted from Equation 6 and thus (P )Cccc ^rom Equation 5 can be
mClX till"
found.
Dennis and Klemm6 and Dennis et al.7 assume that the K2 for pulse-jet
filters can be approximated by the K2 found for reverse air. For ideal
Darcy's filtration, K2 should depend only upon the dust cake structure and
not on the method of cleaning. However, pulse-jet filters may affect the
deposited dust in two ways that are different from the reverse-air filters.
First, pulse-jet filters use nonwoven fabrics and thus the dust deposited
within the fabric and the dust/fabric interface may be significantly dif-
ferent from the woven fabrics used in reverse air. The second difference
2-5
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arises from the dust that is redeposited on the filter after the cleaning
pulse is completed; this dust may have been agglomerated and its cake
structure thereby altered due to the forces of cleaning. Additionally,
even if the K2 from the reverse air could be used for pulse-jets, the K2
correlations that Dennis et al. propose are based on meager data and no
information is available for K2.
Dennis and Klemm6 found that K2 may be affected by the face velocity.
They found, based on meager data for coal fly ash, that they could adjust
K2 from one velocity to another by
(K2)2 = (K2)t (Vi/Vj,)1* (7)
This relationship was used in this analysis to compare the K2 for the
conventional at one velocity, with that at other velocities.
The K2 values found in the control unit of the VanOsdell et al.1 work
varied from 1.9 to 9.2 N-min/g-m.
Figure 2-2 gives a plot of the PDR versus the applied field data found
by VanOsdell et al.l These data were empirically fit to give
PDR = 0.77 exp(-.25f) 5>f>0.75 (8)
PDR = 1.0-.63f + .21f2 - .024f3 f < 0.75 (9)
where PDR = (P - P )CCCC/(P - P ) . . , (10)
r'ESFF v r'conventional ^ J
and f is the applied field in KV/cm. VanOsdell et al.1 show optimum PDR at
field voltages between 2.5 and 3.0 kV/cm. Operation at applied fields
greater than this would not result in much better performance. This work
is based on dust from an industrial coal boiler filtered with Teflon fabric
bags. PDR results were not affected by face velocity over the range (1.5
to 4.0 cm/s) studied at the pilot plant. PDR calculations for this cost
analysis program are based on these equations. The effect of glass woven
fabric was found to increase the PDR. The effect of other fabrics is not
known.
2-6
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ro
i
CC
Q
a.
Applied Field (kV/cm)
Figure 2-2. PDR versus applied field for data from VanOsdell et al.1
Smooth curve from Equations 9 to 11.
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Table 2-1 lists the input options provided in the program. If values
of S , S , and K, are available for the dust/fabric unit of interest, they
re z
should be used as a first choice. If a set of data on P vs. W is available,
Equation 3 will be used to calculate K2-
Thus, it is clear that not much is known or quantified about pulse-jet
filters and about ESFF applied to pulse-jet filters. Appendix A describes
the empirical and theoretical models for conventional pulse-jet filters
that are available in the literature to illustrate some of the parameters
and variables that need to be considered to further develop pulse-jet
models. However, before application of the models described in Appendix A
can be made, more information is needed to test them for different condi-
tions and to test the assumptions more rigorously. Therefore, because of
the lack of well-tested models, a simple approach based on conventional
fabric filtration theory and pilot-plant experimental data is applied in
this study. Table 2-1 summarizes the equations used in the computer program,
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TABLE 2-1. PERFORMANCE MODEL
Input:
Option #1— Pr(Sr) Pe(Se), C.n, t, V, K2, applied field
Option #2--Data set of P P (S ) PCS), C. t, V, applied field f;
ii € 6 t n
the program will calculate K2=(P -P )/((C. Vt)V)
iHoX 6 in
Pressure drop calculation:
(1) W = C.nVt
(2) (P ) conventional = S V + K2 VW
max e
(3) (Pr)ESFF = (Pr) conventional (1-r), r=0.42, Pr=Sr'V
(4) PDR = f (applied field), by Equations 8-10
<5) ESFF = Pr ESFF + "^^conventional ' Pr} X PDR
(6) P ESFF = ((P) ESFF + P ESFF)/2
Output:
ESFF» ^^' PDR'
2-9
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CHAPTER 3
ECONOMIC ANALYSIS AND MEASURES OF MERIT
It Is widely recognized that careful and systematic methods are neces-
sary for the proper evaluation and reporting of the economic feasibility of
a proposed project. Both the EPA and the Navy have published standard
methods8 9 for this type of analysis and both contain essentially the same
elements. They include:
1. Defining the objective
2. Generating alternatives
3. Formulating assumptions
4. Determining costs and benefits
5. Comparing costs and benefits and rank alternatives
6. Performing sensitivity analyses.9
These guidelines will be followed throughout the following discussion
of economic analysis, and the two methods8 9 will be compared and shown to
be essentially the same.
The objective of the pollution control system for this study is to
meet State and EPA requirements for particulate emissions from coal-fired
boilers. In the case of an existing pollution control device, the objective
may be to reduce emissions and/or to reduce operating costs.
The purpose of this report is to determine how well a new pulse-jet
baghouse or a pulse-jet baghouse retrofitted with ESFF hardware can meet
these objectives. By no means do these alternatives represent the only
available systems for particulate control; however, they are the only
systems to be considered here. It is up to the reader to identify and
evaluate the economic feasibility of other alternatives.
3-1
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The third step in an economic analysis is the formulation of assump-
tions. This step is similar to the Descriptive Segment and Specified
Parameters discussed by Uhl.8 It is assumed for the plant that the boiler
is of the pulverized-coal type and that the fly ash has properties similar
to the fly ash encountered by VanOsdell et al.1 at the Waynesboro plant and
in the laboratory. It is further assumed, with respect to economic factors,
that no lead time is required, regardless of baghouse size; the equipment
will be bought outright (i.e., there are no capital recovery costs); there
is a ready supply of civilian labor available for construction and operation
of the baghouse; no changes in plant working capital are required; there
are no existing assets that can be employed in or replaced by construction
of a new or retrofitted baghouse; the life of an existing baghouse is not
changed by retrofitting it with ESFF hardware; the fly ash collected in the
baghouse has no value; and finally, the terminal value of the baghouse or
retrofit hardware is offset exactly by the cost of removing the equipment.
Assumptions specific to the equipment used in the baghouse will be discussed
in Chapter 4.
A measure of merit describes the economic feasibility of a project.
For the purposes of the Navy, the evaluation of a baghouse falls under the
category of a Fundamental Planning Analysis (FPA). A project to retrofit a
baghouse with ESFF hardware to reduce its pressure drop and therefore lower
the operating costs requires a Type I FPA. The construction of a new
baghouse, either with or without ESFF, requires a Type II FPA. A Type I
FPA results in a value of the Savings/Investment Ratio (SIR), which is
similar to the Return on Investment indicator discussed by Uhl.8 Another
measure of merit that can be used to describe a Type I FPA is the payback
period. This quantity is also recognized by Uhl.8 Either of these measures
of merit (SIR or payback period) can be used to determine the economic
feasibility of a project under both Navy and EPA guidelines.
The measure of merit that characterizes a Type II FPA is the equiv-
alent uniform annual cost. For this study, the other particulate control
alternatives are unknown and therefore it may not always be possible to
calculate the equivalent annual cost. It is possible to calculate the Net
Present Value (NPV), which can then be used to determine the equivalent
3-2
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annual cost when alternatives are formulated. Therefore the NPV will be
the result of the Type II FPA reported by the computer program.
A rigorous evaluation of a project's measure of merit would incorporate
the effects of depreciation, tax credits, inflation, and other indirect
costs on the annual payment. The consideration of these factors is beyond
the scope of this project, though it is still desired to estimate the
appropriate measures of merit. Therefore, in the computer programs described
in Chapter 5, the reported measures of merit are based on the capital cost
and the operation and maintenance costs only. As such, the reported values
represent "before-tax" estimates of the measures of merit. For those who
wish to pursue a more rigorous evaluation of the measure of merit, the
capital cost and operation and maintenance costs are also reported.
In the following sections the three measures of merit—SIR, payback
period, and NPV—are described and example calculations are given.
3.1 CALCULATION OF SAVINGS/INVESTMENT RATIO
The Savings/Investment Ratio gives a direct measure of the "profita-
bility" of a proposed modification in current operations. Before the
savings gained by retrofitting a baghouse with ESFF are calculated, the
annual operating and maintenance (O&M) costs for the ESFF baghouse must be
computed. This amount is then subtracted from the current annual O&M costs
to determine the annual savings in current dollars. This difference must
be positive if ESFF is to offer any economic advantage over the status quo.
Before determining the economic benefit of an ESFF retrofit over the remain-
ing life of the baghouse, the cumulative savings must be computed by use of
the cumulative uniform series factor. This factor discounts the value of
money that is to be paid out in the future to the value at the present
time. This factor is calculated as:
h = exp(n-1n(l+R)) - 1
n ln(l+R)-exp(n-ln(l+R))
where
n = the number of years the annual payments are to be made
R = the effective annual discount rate.
3-3
-------
The present value of a series of uniform annual payments is then calculated
as:
SPV = A b (12)
where
A = the uniform annual payment.
P
The SIR is then computed as the ratio of the present value of the annual
savings to the investment cost of retrofitting the baghouse with ESFF
hardware.
For example, assume a retrofit project required one-time costs of
$50,000 and thereafter provided an annual savings of $7,000 over the remain-
ing 10 years in the life of the baghouse. The present value of the savings
that would be realized over the 10-year period is:
SPV = 7,000 - exp(10.1n(l+0.1)) - 1
1 n(l+0. 1) • exp(10 • 1 n(l+0. 1) )
=7,000 • 6.447
= $45,128 .
It has been assumed here that the effective annual discount rate (R) is
10 percent. The savings/investment ratio is thus
SIR = $45.128 _
SIR 50,000 ~ 0'902 '
This result indicates that in this case the retrofit project would not be
advantageous.
3.2 CALCULATION OF PAYBACK PERIOD
According to the Navy's "Economic Analysis Handbook,"9 the "discounted
payback occurs when the present value of accumulated savings equals the
present value of the investment." Mathematically this can be expressed as:
Payback period = - - - (13)
3-4
-------
where
I = the amount Invested
A = the uniform annual payment in current dollars
R = the effective annual discount rate.
Here it has been assumed that there is no lead time involved in realizing
the benefits of the ESFF retrofit.
The payback period can be used in an interesting way to evaluate the
example from the previous section. Using equation 13 the payback period
can be calculated as:
50,000
7'°°°>
= 12 years .
This result can be interpreted to mean that the investment in retrofit
equipment would break even after 12 years of operation and return a profit,
so to speak, after the 12th year.
3.3 CALCULATION OF NET PRESENT VALUE
The net present value is the sum of the present values of the annual
costs for each year of equipment life. It is assumed that the payment
schedule for capital and operating costs is on an annual basis and that the
project requires no lead time. If the annual cost is constant, as is
assumed here, the net present value of the annual payments can be calculated
from the cumulative uniform series factor defined in Section 3.1. The
capital cost must be added to the annual cost to determine the total NPV.
It has been assumed that there will be no capital recovery costs associated
with the purchase of the equipment. In other words, the equipment will be
purchased outright with no financing. As an example of an NPV calculation,
consider a plant which costs $100,000 to purchase and install and requires
$10,000 each year for operating and maintenance. The NPV of this plant for
N = 12 years is:
3-5
-------
NPV = $100,000 + $10,000 - exp<12.1n(l+0.1)> - 1
1n(l+0.1)•exp(12-1n(l+0.1))
= $100,000 + $10,000 • 7.149
= $171,490
where it has been assumed that R = 0.1. If it were necessary to finance
the equipment purchase, then the annual financing cost would have to be
included in the NPV.
Before any measures of merit can be calculated, it is necessary to
determine the capital and operating costs. In Section 4 the equations for
predicting the cost of pulse-jet baghouses, both with and without ESFF, are
described in detail. Equations for estimating annual operating and mainte-
nance costs are also described.
3-6
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CHAPTER 4
PULSE-JET BAGHOUSE COST ESTIMATION
4.1 INTRODUCTION
Each of the measures of merit discussed in the previous section requires
knowledge of the initial investment in equipment and the annual cost of
operating the equipment. The initial investment is the capital cost of the
project which includes the cost of purchasing and installing the baghouse
system. The annual cost consists of the yearly operating and maintenance
costs as well as the capital recovery costs. The estimation of these costs
is the subject of this section.
Neveril10 presents a complete method for estimating the capital and
operating costs for pulse-jet baghouses. His method is used here and will
be reviewed in detail in this section.
The capital cost of a large project is typically broken into two
categories: direct costs and indirect costs. The direct cost is further
divided into purchased equipment costs and installation costs as shown in
Table 4-1. For any project, the cost of the baghouse, ESFF hardware (if
necessary), auxiliary equipment, controls, taxes, and freight are included
within the purchased equipment cost subcategory. The installation cost
includes such items as foundations and supports, electrical work, piping,
etc., as needed for the baghouse installation. The indirect costs include
engineering, construction and field expenses, construction fee, startup,
performance testing, and contingencies. The sum of the direct and indirect
costs is the capital cost.
The estimation of the capital cost proceeds as follows:
1. The costs of the baghouse, insulation, ducting, fan, ash
conveyor, and ash pond are estimated or obtained from vendor
quotes.
2. The sum of these costs is multiplied by a set of factors to
include the costs of instrumentation and controls, taxes,
4-1
-------
and freight. The sum of these quantities is the purchased
equipment cost.
3. The installation cost is obtained by multiplying the pur-
chased equipment cost by a set of factors to account for the
various items required for installation.
4. The sum of the purchased equipment cost and the installation
costs is the direct cost.
5. The indirect cost is obtained by multiplying the purchased
equipment cost by a set of factors to account for the various
items in this category.
6. The sum of the direct and indirect costs is the capital cost
of the project. This procedure will be illustrated in an
example at the end of this section.
The cost factors listed in Table 4-1 for estimation of instrumentation,
freight, installation, and indirect costs are values for typical systems.
That is, the plant is assumed to be of moderate size and relatively easy to
get to; the site poses no difficulties—i.e., adequate room, no blasting
required; and the process is well established (this is not a good assumption
for an ESFF baghouse). Oftentimes these assumptions will be invalid and
the use of the factors in Table 4-1 would yield cost estimates that are too
high or too low. Consequently, it is often necessary to adjust these cost
factors. Neveril10 has presented guidelines for making the necessary
adjustments and these are presented in Table 4-2. The use of these adjust-
ment factors will be presented in the example at the end of this section.
Operating costs can be estimated based on the size of the baghouse
and/or the gas flow rate through the baghouse. These costs include oper-
ating labor and material, maintenance labor and material, overhead, property
tax, insurance, administration, and capital recovery cost as shown in Table
4-3. The labor and materials costs are estimated directly from the size of
the equipment, the labor rate, and the material costs. The overhead cost
is computed as a fraction of the sum of the operating and maintenance labor
and materials costs. The annual costs of property tax, insurance, and
administration are estimated as fractions of the capital cost. The capital
recovery cost is calculated from the capital cost, interest rate, and
expected life of the equipment.
4-2
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TABLE 4-1. ESTIMATION OF CAPITAL COSTS
Direct Costs Typical Cost Factor
Purchased Equipment Costs
Baghouse As per Equation 14
ESFF hardware As per Equation 25
Auxiliary equipment As per Equations 15-24
Instruments and controls 0.10
Taxes 0.03
Freight 0.03
Installation Costs
Foundation and supports 0.04
Erection and handling 0.50
Electrical 0.08
Piping 0.01
Insulation 0.07
Painting 0.02
Site preparation 0.01
Facilities and buildings 0.02
Indirect Costs
Engineering and supervision 0.10
Construction and field expenses 0.20
Construction fee 0.10
Startup 0.01
Performance test 0.01
Contingencies 0.03
Capital cost = direct costs + indirect costs
4-3
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TABLE 4-2. COST ADJUSTMENT FACTORS
Cost adjustment
A. Instrumentation
1. Simple, continuous manually operated 0.5 to 1.0
2. Intermittent operation, modulating flow with
emissions monitoring instrumentation 1.0 to 1.5
3. Hazardous operation with explosive gases and
safety backups 3
8. Freight
1. Major metropolitan areas in continental United States 0.2 to 1.0
2. Remote areas in continental United States 1.5
3. Alaska, Hawaii, and foreign countries 2
C. Handling and Erection
1. Assembly included in delivered cost with supports,
base, skids included. Small- to moderate-
size equipment 0.2 to 0.5
2. Equipment supplied in modules, compact area
site with ducts and piping less than 200 ft
in length. Moderate size system 1
3. Large system, scattered equipment with long
runs. Equipment requires fabrication at site
with extensive welding and erection 1 to 1.5
4. Retrofit of existing system; includes removal
of existing equipment and renovation of site.
Moderate to large system 2
0. Site Preparation
1. Within battery limits of existing plant;
includes minimum effort to clear, grub,
and level 0
2. Outside battery limits; extensive leveling
and removal of existing structures; includes
land survey and study 1
(continued)
4-4
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TABLE 4-2 (continued)
H.
3. Requires extensive excavation and land ballast
and leveling. May require dewatering and pilings
Facilities and Buildings
1. Outdoor units, utilities at site
2. Outdoor units with some weather enclosures.
Requires utilities brought to site, access
roads, fencing, and minimum lighting
3. Requires building with heating and cooling,
sanitation facilities, with shops and office.
May include railroad sidings, truck depot,
with parking area
Engineering and Supervision
1. Small capacity standard equipment, duplication
of typical system, turnkey quote
2. Custom equipment, automated controls
3. New process or prototype equipment, large
system
Construction and Field Expenses
1. Small capacity systems
2. Medium capacity systems
3. Large capacity systems
Construction Fee
1. Turnkey project, erection and installation
included in equipment cost
2. Single contractor for total installation
3. Multiple contractors with A&E firm's
supervision
Cost adjustment
2
0
0.5
1 to 2
.5
1
1.5
.5
(continued)
4-5
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TABLE 4-2 (continued)
Cost adjustment
I. Contingency
1. Firm process 1
2. Prototype or experimental process subject to change 3 to 5
3. Guarantee of efficiencies and operating speci-
fications requiring initial pilot tests,
deferment of payment until final certification
of EPA tests, penalty for failure to meet
completion date or efficiency 5 to 10
4-6
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TABLE 4-3. ANNUAL OPERATING EXPENSES
Direct Operating Costs
Operating labor
Operator
Supervisor
Operating material (bags)
Maintenance
Labor
Material
Utilities
Compressed air
Electricity
Indirect Operating Costs
Overhead
Property tax
Insurance
Administration
Capital recovery cost
As per Equation 26
As per Equation 26
As per Equation 28
As per Equation 27
As per Equation 27
As per Equation 29
As per Equations 30-32
80% of (operating
labor and material
maintenance)
1% of capital cost
1% of capital cost
2% of capital cost
As per Equation 33
plus
4-7
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In the subsections below, equations for estimating the capital cost of
a pulse-jet baghouse, ducting, ash removal system, fan, and ash pond will
be described. The ESFF hardware, if required, would be included with the
cost of these items in the purchased equipment cost but for the sake of
clarity the description of ESFF hardware costs will be described separately.
The estimation of operating and maintenance costs will also be described.
At the end of this section, a comprehensive example illustrating the use of
all of these factors will be presented.
4.2 CAPITAL EQUIPMENT
The cost of a carbon steel, shop-assembled, continuous-duty pulse-jet
baghouse can be estimated from the equation
CTb = 5,370 + 81.8 * An (14)
where
CT. = the cost of the baghouse
A = the net cloth area for flow in square meters.
Similarly, the cost of insulation for the baghouse is calculated as
CTins = 4'910 + 25'8 An • (15)
The cost for 15.2 m (50 ft) of 3/16-in ducting to the baghouse is
calculated based on flow rate (Q) by
CTduct = 15'2 * ("5-77 + 177 • 1.128 • 0.2562-0/5) (16)
where the flow rate has units of actual cubic meters per second. Inherent
in this equation is an assumed flow rate of 15.3 m/s (3,000 ft/min), which
is typical for flue gases. The costs of the inlet/outlet dampers are
estimated as
CTdamp = i'100 + 64'8'Q W>
and the cost of a backward curved fan capable of delivering a 50-cm (20-in)
H20 static pressure with motor and starter is estimated as
CTfms = 2,600 + 528.5-Q . (18)
4-8
-------
There are two elements to an ash disposal system: the conveyor to
move the ash and a pond in which to deposit it. The cost of an ash con-
veyor is proportional to the amount of ash to be moved and the length of
the conveyor. The amount of ash to be moved by the conveyor is propor-
tional to the gas flow rate. For flue gas flow rates less than 47.2 acms
(100,000 acfm) a 23-cm (9-in) diameter pipe is sufficient and the cost of
the conveyor is
CT = 632.5 + 216.5 • L (19)
con c
where L is the length of the conveyor. For larger gas flow rates, a 30-cm
(12-in) pipe size is recommended. The cost of a 30-cm (12-in) diameter
conveyor system is:
CTcon = 747'5 + 222'4 * Lc ' (20)
For the purposes of this study, a 305-m (1,000-ft) conveyor is assumed
sufficient to transfer the fly ash from the baghouse hoppers to the ash
pond.
It is assumed here that the fly ash collected in the baghouse has no
intrinsic value and must be disposed of in an ash pond. The cost of the
ash pond is dependent on its size, which is determined by the amount of ash
collected. This cost is also dependent on the presence or absence of a
flue gas desulfurization (FGD) unit in the pollution control system. If an
FGD system is included, a larger pond will be required for ash disposal;
however, because of a generous economy of scale, the unit cost will be
lower. Only the portion of the ash pond needed for disposal of the baghouse
fly ash is assigned to the control device for costing purposes. The amount
of ash collected is the product of the amount of ash generated times the
efficiency of the collector. The amount of fly ash generated in the boiler
is calculated by
fraction fly ash x boiler size
ash generated - CQal hgat va]ue x steam cycle efficiency
4-9
-------
where
fraction fly ash = fraction of ash in coal that leaves boiler in flue
gas,
boiler size = net generating capacity
coal heat value = unit energy per unit mass
steam cycle efficiency = thermodynamic efficiency of energy conversion.
The amount of ash generated is calculated assuming 100 percent capacity;
however, the pond size is calculated for the actual capacity:
_2
pond size = 8.267-10 x ash collected x capacity factor . (22)
This equation yields pond size (acre-foot) assuming a pond life of 30 years.
_2
The constant 8.267 x 10 acre-ft/kg/h is derived from data reported by
Ponder et al.12 The cost of the pond is calculated from the equation
actual pond cost = 13,648 x (pond size) . (23)
Equation 23 was derived from data in the report by Ponder et al.12 and
includes the cost of land, excavating, and diking. The constant 13,648 in
the equation is the cost (in dollars) of a pond with 1 acre-ft of volume.
Equation 23 does not include any charges for indirect costs or contingencies.
These costs are included in the equation:
total pond cost = actual pond cost x 1.395 x 1.2 (24)
where 1.395 is an indirect cost multiplier and the 1.2 is for a 20-percent
contingency. The cost for the ash pond is primarily labor, thus the indirect
multiplier in Equation 24 accounts for less overhead, freight, and insurance
than it would in other subsystems.
4.3 ESFF HARDWARE
The cost of hardware required to equip a new conventional pulse-jet
baghouse with ESFF or to retrofit an existing baghouse with ESFF is tne
same. A prototype baghouse was specified (see Figure 4-1) to determine
these costs. For the sake of simplicity, it was assumed that the baghouse
4-10
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Width = A/N feet
T
10ft
V
000
o o
o
o o o
o o
o
Square compartment
with N bags on
1-ft centers
O
O O
o o o
o o o o
o
o o
o o o
Length =-N feet
(a)
J, 'A, A, A* & A* .LA* A*
TTTVTTTT TT
r
(b)
Figure 4-1. Assumed ESFF prototype.
bus
4-11
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ft ft ft ft
R R R
ft ft ft ft ft ft ft ft ft ft/
ft i ft ft ft ft
TTTTTTTT TTT
I
r
(c)
TR Set Buses
Note: Each row of bags is connected to the TR set bus at the top
and bottom.
Figure 4-1 (continued).
4-12
-------
has only one large, square compartment. The bags in the prototype are
placed on 0.3-m (1-ft) centers (i.e., 0.3 m apart.) Therefore, if there
are N bags in the baghouse, the number of bags along any side of the compart-
ment is VN. Since the bags are spaced 0.3 m (1 ft) apart, the length of
the row of bags is 0.3 • «/N m (see Figure 4-la).
The amount of wire needed to connect each of the bag cages to the
transformer-rectifier set can be determined with the aid of Figure 4-lb.
It has been assumed that the buses that carry the current for each row of
bags are located 0.3 m above and below the row of bags. Thus, there must
be 0.3 m of wire to connect each bag to the upper bus and 0.3 m of wire to
connect each bag to the lower bus. The length of the bus is the same as
the length of the row, or VN m. Finally, each row of bag cages must be
connected to the TR-set. This connection is illustrated in Figure 4-lc.
The buses for each row of bags are connected to the TR-set buses by an
0.3 m length of wire at the end of the row. The TR-set buses extend the
length of the baghouse so they are 0.3 • VN m long. These TR-set buses are
connected to the TR-set by the lengths of wire indicated in the figure. In
summary, the amount of wire needed to connect a square baghouse with N bags
to a power supply is:
Connect each bag to upper bus (N bags) 0.3 • N m
Connect each bag to lower bus (N bags) 0.3 • N m
Length of upper bus for each row, N rows 0.3 • N m
Length of lower bus for each row, N rows 0.3 • N m
Connect upper bus for each row to TR-set bus 0.3 'VN m
Connect lower bus for each row to TR-set bus 0.3 -^N m
Connect upper TR-set bus to TR-set 0.3 m
Connect lower TR-set bus to TR-set 4.2 m
Total wire required for baghouse 4.5 + 0.3 (4N + 2>/N)m
Other hardware required for ESFF installation includes connectors for
coupling wires to buses (two per bag), clamps to hold the bus wires in
place (two per bag), and ceramic plug connectors to make connections to bag
cages. This hardware must be able to withstand the abrasive, high tempera-
ture, and occasionally acidic atmospheric within a baghouse. Likewise the
wire used inside the baghouse must be able to withstand these conditions
4-13
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with the added requirement that it be able to withstand the high voltages
(0-5 kV) that are within the operating range of ESFF. For these reasons,
18-gauge, Teflon®-coated silver-plated copper wire rated to withstand 10 kV
DC has been specified for the ESFF baghouse.
Operating experience has shown that a current density of 0.54 mA/m2
of fabric area represents the upper limit of operation for ESFF. Currents
higher than this can burn holes in the bag fabric. This current will be
used when specifying the number of power supplies required for the baghouse.
Because of the relatively low voltages required for ESFF as compared to an
electrostatic precipitator, a power supply with dry insulation can be used.
The TR set that is assumed for the prototype baghouse can supply a current
of 1 amp at 10 kV with a primary voltage of 480 V.
Cost quotes have been obtained for all of these items and they are
summarized in Table 4-4.
The cost of the ESFF hardware is the sum of the cost of the wire, the
connector hardware, and the power supply:
CESFF = N x $6.20 + $3.94 x [4.5 + 0.3 x (4N + 2VN) + (25)
$1,835 x {7.85 10"4 N}
The first term is the cost of the connector hardware, the second term is
the cost of the wire, and the last term is the cost of the power supply
based on a maximum current of 0.54 mA/m2 and a bag area of 1.46 m2 (6 in
diameter, 10 ft length). The braces around the last term in the equation
denote that an integer number of power supplies are required.
4.4 OPERATING AND MAINTENANCE COSTS
Operating costs include the cost of labor, materials, and energy to
operate the baghouse. Some of these costs are fixed (i.e., determined by
the size of the equipment) and some of the costs vary with the flow rate
through the baghouse. As an example of a fixed charge, the cost of operat-
ing labor is calculated from the following formula:
Cost of
Op. Labor = (8>760/8) x (1-5+2.4 x 10 4 x An) x 1.333 x 1.8 x olr (26)
4-14
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TABLE 4-4. ESFF HARDWARE COSTS
Ceramic plugs 2 per bag @ $2.00 ea = $4.00 per bag
Bus connectors 2 per bag @ $1.00 ea = $2.00 per bag
Wire clamps 2 per bag @ $0.10 ea = $0.20 per bag
Total connector hardware $6.20 per bag
Teflon _coated high voltage wire $3.94/m
rated to 10 kV DC
Transformer-rectifier set:
1 amp, 10 kV, dry insulation,
480 V primary voltage,
simple controls $1,835 ea
4-15
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where
A = net cloth area for flow in square meters, and
n
olr = operating labor rate ($/hr)
In this equation, the labor requirement is a minimum of 1.5 man-hours per
shift with an additional man-hour per shift required for each 4,180 m2
(45,000 ft2) of cloth area in the baghouse. The first term in the equation
is the number of shifts per year at 8,760 h/yr. The factor 1.333 includes
a surcharge of 15 percent for supervision of operating labor at a labor
rate 16 percent higher than the operator's rate (olr). The factor of 1.8
accounts for overhead.
Other fixed charges include the cost of maintenance labor and materials,
bag replacement, and overhead. The cost of maintenance labor and materials
is calculated as:
CT . = (8,760/8) • (1.5 + 2.4 • 10"7 • A ) • 0.5 • 2.0 • 1.8-mlr (27)
m im n
where the first two terms are the same as in the operating labor equation.
The 0.5 is used to indicate that the requirement of maintenance labor is
one-half that of operating labor. It is assumed that maintenance material
and labor costs will be equivalent, so the term 2.0 is used to account for
maintenance materials. The multiplier of 1.8 accounts for overhead and the
term mlr stands for maintenance labor rate which will generally be higher
than the operating labor rate.
Bag replacement cost is another item that varies with size of the
baghouse. This cost can be calculated from the equation
CTrep = d+OHF)-CTfab/bag life •
4.49-An°-835, A < 5,110 m2
1.75-An0'946, 5,11016,722 m2
(28)
where
CT = the cost of replacing the bags and cages
4-16
-------
= the unit cost of the fabric
OHF = a multiplier that accounts for overhead costs.
Implicit in this equation is the assumption that the replacement cost is
spread evenly over the life of the bags. If this assumption is not valid
(i.e., all bags are replaced in a single year), there will be a small error
in the measure of merit calculated below.
The cost of compressed air for the cleaning pulse of the pulse-jet
baghouse is also assumed to be independent of flow through the baghouse.
This annual cost is calculated as
CT
pulse
4.49-An°'835, An<5,110 m2
1.75-An°-946, 5,11016,722 m2
(29)
based on 25 ftVmin of air for each 1,000 ft2 of fabric, where CT.U. is the
KWn
cost of electricity per kilowatt hour.
The only other annual costs that are independent of flow rate through
the baghouse are the administration, taxes, and insurance costs. These
costs are assumed to be constant percentages of the turnkey cost of the
baghouse.
The only variable baghouse costs are associated with electricity for
fans and ash removal equipment. The annual cost of electricity for a fan
operating 8,760 h/yr at a motor efficiency of 90 percent and a fan efficiency
of 60 percent is
CTfms = 8,760 - 0.182 . Q - AP^ - CT^ (30)
where
Q = the flow rate in acms
AP = the average pressure drop across the baghouse in cm H20.
This cost can be modified further by the plant capacity factor. That is,
if a plant is only operating at 70 percent of capacity, the cost of electri-
4-17
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city for the fan will be 70 percent of the value calculated above. Similarly,
the cost of electricity for conveying fly ash is
(31)
where
._ = the concentration of fly ash at the inlet of the baghouse in
kg/m"
in ,._, 3
The electricity requirement for the ESFF cages is the product of the
applied field, the current, and the number of hours the unit is in operation.
Specifically,
ESFF power = Applied field • electrode spacing • bag area
(32)
current density 0 -,.-„
• o ' 8>76°
The constant 0.6 is the assumed efficiency of a.c. to d.c. conversion. The
current density used in this equation is the average operating current
density. Experience1 has shown that an operating current density of 0.27
mA/m2 is sufficient for ESFF.
The total annual operating and maintenance cost is the sum of the
operating labor; maintenance labor and material; bag replacement labor and
material; and electricity cost for the compressed air source, ID fan, ash
pumps, and ESFF hardware.
4.5 ANNUAL CAPITAL COST
When the Navy purchases equipment, it does not have to consider the
cost of financing that purchase, but for those who wish to use this model
for predicting the costs to public utilities or industrial organizations,
the financing cost must be included. The capital recovery factor is used
to determine the annual payment of principal and interest. This payment is
calculated according to the formula:
A = P _ (33)
4-18
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where
A = annual payment,
P = capital cost,
i = annual interest rate, and
N = life of the equipment.
The total annual cost can then be calculated as the annual payment for
capital equipment plus the annual operating and maintenance costs.
4.6 EXAMPLE CALCULATIONS
As an example of the application of the capital and O&M cost equations,
consider the following comparison between a conventional pulse-jet baghouse
and an ESFF pulse-jet baghouse. Both baghouses are designed to produce an
average pressure drop of 10 cm H20; but the conventional baghouse is designed
with an air-to-cloth ratio of 0.02 (m3/s)/m2 whereas the ESFF baghouse can
operate at 0.03 (ms/s)/m2. Other pertinent parameters are listed in Table 4-5
The capital and O&M costs will be computed along with the Net Present
Value and the Equivalent Uniform Annual Cost.
For the ESFF baghouse, the cost of the equipment can be determined
from Equations 14 through 25 based on a net cloth area of
. _ 200 ma/s _ , (.,.-, m2
An ~ 0.03 (mVs)/m* ' 6'667 m
and the number of bags in the ESFF baghouse is
N = 6,667 m2/1.46 mVbag = 4,566 bags .
CTfa = 5,370 + 81.8 x 6,667 = $ 550,731
CTEspF = 6.2 x 4,566 + 3.94 x (4.5 + 0.3 (4 x 4,566 + 2^47566))
+ 1,835 (7.85 x 10"4 x 4,566} = 57,415
CT. = 4,910 + 25.8 x 6,667 = 176,919
CT_, = 15.2 (-5.77 + 177 x 1.128 x 0.2562(200)'*) = 10,908
duct
4-19
-------
TABLE 4-5. DESIGN AND OPERATING PARAMETERS FOR THE
EXAMPLE CALCULATIONS
Flowrate
Inlet dust concentration
Operating labor rate
Maintenance labor rate
Material overhead fraction
Cost of fabric
Bag life
Unit cost of electricity
Average pressure drop
Applied field strength
Equipment life
Effective annual discount rate
200 m3/s
7 g/m3
$10.00/hr
$12.00/hr
10%
$4.65/m2
4 years
$0.06/kWh
10.0 cm H20
3.0 kV/cm
15 years
12.0%
4-20
-------
= 1,100 + 64.8 x 200 =
= 2,600 + 528.5 x 200 =
CTcon = 747'5 + 222'4 X 305 =
$ 14,060
108,300
68,580
rt _ O
Pond size = 8.267 x 10 acre-ft/kg/hr x 7 x 10 kg/m3 x 200 m3/s
x 3,600 s/hr
= 416.6 acre-ft
Pond cost = 13,648 (416.6)
Total
0.583
459.621
$1,446,534
The purchased equipment cost can be calculated using the factors listed in
Table 4-1.
Purchased Equipment Costs
Baghouse
ESFF hardware
Auxiliary equipment
Instruments and controls
Taxes
Freight
Purchased equipment cost
0.10 x 1,446,534 =
0.03 x 1,446,534 =
0.05 x 1,446,534 =
$ 550,731
57,415
838,388
144,653
43,396
72,327
$1,706,910
The installation costs and .indirect costs are also calculated using
the factors in Table 4-1 and based on purchased equipment cost.
Installation Costs
Foundations and supports
Erection and handling
Electrical
Piping
Insulation
Painting
Site preparation
Facilities and buildings
Total
Indirect Costs
Engineering and supervision
Construction and field expenses
Construction fee
Startup
Performance test
Contingencies
Total
0.04 x 1,706,910 = $ 68,276
0.50 x 1,706,910 = 853,455
0.08 x 1,706,910 = 136,553
0.01 x 1,706,910 = 17,069
0.07 x 1,706,910 = 119,484
0.02 x 1,706,910 = 34,138
0.01 x 1,706,910 = 17,069
0.02 x 1,706,910 = 34,138
$1,280,182
0.10 x 1,706,910
0.20 x 1,706,910
0.10 x 1,706,910
0.01 x 1,706,910
0.01 x 1,706,910
0.03 x 1,706,910
= $
170,691
341,382
170,691
17,069
17,069
51,207
$ 768,109
4-21
-------
Capital cost = $1,706,910 + $1,280,182 + $768,110 = $3,755,202
Thus the capital cost is $3.76 million.
In the calculation that led to the value of $3.76 million, it was
assumed that the process in question is well established. This assumption
is inappropriate for ESFF at this time. According to Table 4-2 the engineer-
ing and supervision cost and the allowance for contingencies should be
increased when the process is not well established. The engineering cost
should be tripled and the contingency allowance should be increased by a
factor between 3 and 5. The cost of the baghouse would thus be:
Purchased equipment cost $1,706,910
Installation cost $1,280,182
Indirect Costs
Engineering and supervision 3 x 0.10 x 1,706,910 = $ 512,073
Construction and field expenses 0.20 x 1,706,910 = 341,382
Construction fee 0.10 x 1,706,910 = 170,691
Startup 0.01 x 1,706,910 = 17,069
Performance test 0.01 x 1,706,910 = 17,069
Contingencies 5 x 0.03 x 1,706,910 = 256,036
Total $1,314,320
Capital cost = $1,706,910 + $1,280,182 + $1,314,321 = $4,301,413
This is the capital cost of the ESFF baghouse with the cost of inexperience
and uncertainty taken into account.
The cost of the conventional pulse-jet baghouse can be estimated based
on a net cloth area of:
and the number of bags is
N = 10,000 m2/1.46 mVbag = 6,850 bags.
The capital cost of the conventional baghouse can be calculated as
above, excluding the ESFF hardware costs and the "uncertainty" costs. The
resulting capital cost is $4.74 million. This cost is higher than the cost
of the ESFF pulse-jet baghouse because it is 50 percent larger.
4-22
-------
The annual operating and maintenance cost for the ESFF baghouse can be
calculated with equations 26 through 32.
~4
CToo lahnr = (8,760/8) x (1.5 + 2.4 x 10~ x 6,667) x 1.333 x 1.8
H x 10.0 = $81,468
CTmin = (8«760/8) x (1.5 + 2.4 x ifl"4 x 6,667) x 1.8 x 12.0 = $73,321
CTrep = (1 + o.l) x (4.65/4) x 1.75 (6,667)0'946 = $9,274
CTpulse = 66'74 x °-06 x 1'75 (6,667)0'946 = $29,041
CTfms = 8,760 x 0.182 x 200 x 10 x 0.06 =$191,318
CTash = 3.48 x 10s x 200 x 7 x 10~3 =$487,200
ESFF er = 3.0 x 2 x 6,667 (0.27/0.6) x 8,760 x 0.06/1,000 = $9.461
Total Direct Operating Costs 881,083
Indirect Operating Costs
Overhead = 0.8 x (81,468 + 73,321) =$123,831
Property tax (no property tax on Government property) 0
Insurance = 0.01 x (4.3 x 10s) = 43,000
Administration = 0.02 x (4.3 x io6) = 86,000
Capital recovery cost (no capital recovery costs _ 0
for Government purchases)
Total indirect operating costs =$252,831
Total annual operating costs = 881,083 + 252,831 = $1,133,914
The high cost of ash disposal in the above calculations is due to the high
inlet dust loading.
A similar analysis for a conventional pulse-jet baghouse, excluding
ESFF power costs, yields a Direct Operating Cost of $929,448 and an Indirect
Cost of $297,988. The Total Annual Operating Cost is thus $1.23 million.
The operating costs for the conventional baghouse are higher than the costs
for the ESFF baghouse because the operating labor costs and maintenance
labor and material costs are assumed proportional to the size of the baghouse
Thus, the size difference greatly outweighs the magnitude of the ESFF
power, so the ESFF operating costs are actually less than the conventional
operating costs.
4-23
-------
Now that the capital and operating costs have been estimated, the Net
Present Value can be calculated.
NPV = capital cost + annual O&M cost x cumulative uniform series
factor ESFF baghouse:
NPV . $4.3 x 10e + $1.13 x - 1n (l2) 0.12)
= $4.3 x 106 + $1.13 x 106 • 7.2118
= $12.45 x 106.
r • •• * 11 •* A i /» + /CUAP\ Net Present Value (NPV)
Equivalent Uniform Annual Cost (EUAC) = cumulative Uniform Series Factor
- $12.45 x 1Q6 _ 6
7.2118 ~ $1'73 10
Conventional Baghouse
NPV = $4.74 x 106 + $1.23 x 106 • 7.2118
= $13.61 x 10s
EUAC = -- = $1.89X106 .
Thus, in terms of the equivalent uniform annual cost, the conventional
baghouse costs $160,000/yr more than the ESFF baghouse. Based on the
design parameters listed in Table 4-5, the preceding analysis indicates
that an ESFF baghouse would be the best choice.
4.7 ACCURACY OF CAPITAL COST PREDICTIONS
All of the equations presented in Section 4.2 for predicting the cost
of equipment were developed from vendor quotes. One of the subtasks of
this contract was to develop an independent check of the accuracy of those
equations. Unfortunately, there is very little data published in the
literature on the cost of pulse-jet baghouses. As a result, ETS, Inc., of
Roanoke, Virginia, was hired as a consultant with the task of obtaining new
4-24
-------
vendor quotes for pulse-jet baghouses. The report from ETS is included in
Appendix C of this report.
Three different sizes of baghouses were priced: 26 acms, 85 acms, and
165 acms (55, 180, and 350 k acfm). The equipment includes the baghouse,
insulation for the baghouse, woven glass bags and cages, inlet and outlet
manifolds and dampers, hopper heaters, controls, and structural supports.
The baghouses were specified with air-to-cloth ratios of 0.02 m/s (4 ft/
min). With this information, equations 15, 16, 18, and 29 were used to
develop the costs in Table 4-6. The quotes obtained by ETS include the
cost of controls and structural supports for the baghouse. To account for
these costs, the factor in Table 4-1 for instrumentation and controls (10%)
was applied to the sum of the capital costs to get an estimate of the
purchased equipment cost. The cost of structural support was estimated
with the factor from Table 4-1 based on the purchased equipment cost. The
calculated cost is in terms of December 1977 dollars so the calculated
costs are multiplied by the ratio of the Chemical Engineering plant cost
indexes for 1977 and 1983 (310/204).
The agreement between the predicted values and the reported values is
surprising in view of the fact that they are both based on vendor quotes.
Typically such price quotes can vary by a factor of 2 between different
vendors. It should be noted that the cost modeling equations are based on
design standards that are at least 7 years old, so that changes since then
are not included in the costs reported in the table. It should also be
noted that this comparison does not include the price of ducting, ash
conveying systems, ash ponds, or installation. Also, at the time of this
writing there are no data available to validate the ESFF costs.
In summary, the equations for predicting the cost of the baghouse,
insulation, dampers, and fabric seem to be in good agreement with expected
values. The cost predictions of ESFF hardware, other auxiliary equipment,
and operating and maintenance costs have not been validated. Neveril
reports that the capital and operating and maintenance cost equations
(except the ESFF hardware) should be accurate to ±20 percent and this is
consistent with the results presented here. The reliability of the cost
equation for ESFF hardware is unknown. The prototype system specified in
4-25
-------
TABLE 4-6. COMPARISON BETWEEN PREDICTED VALUES AND VENDOR QUOTES
ro
en
Item Equation No.
Baghouse 14
Insulation 15
Bags 28
(OHF = 0.1, Cp = 0.6)
Dampers 17
Total
Instruments and controls
(Table 4-1: 10%)
Purchased equipment cost
Foundation and supports
(Table 4-1: 4%)
Capital cost (December
1977)
Purchased equipment cost
(CE plant cost index) (mid-
1983)
Unit cost ($/m2 fabric)
Vendor quote ($/m2 fabric)
Ratio: Predicted cost/
vendor quote
Q = 26 ma/s
A = 1,275 m2
109,870
37,910
11,380
2,783
161,943
16,194
178,137
7,125
185,262
281,526
221
258
0.856
Cost ($)
Q = 85 mVs
A = 4,274 m2
354,970
115,310
31,192
6,608
508,080
50,808
558,888
22,356
581,244
883,263
207
215
0.963
Q = 165 m3/s
A = 8,194 m3
675,690
216,590
57,034
11,810
961,124
96,112
1,057,236
42,289
1,099,525
1,670,847
204
183
1.115
-------
Section 4.2 is quite simple and it is likely that some necessary items have
been overlooked. On the other hand, the cost of the connector hardware
seems high. In situations like this, where the technology is new and has
never been implemented on a full scale, it is common to specify the accuracy
as ±30%.
4-27
-------
CHAPTER 5
COMPUTER PROGRAM
A computer program has been written that incorporates the performance
and cost models described earlier. The program allows the user to predict
pulse-jet baghouse performance, and then use the air-to-cloth ratio, air
flow rate, and the predicted pressure drop to predict the capital cost and
annual operating costs. The appropriate measure of merit (NPV for new
baghouses and SIR and payback period for baghouses retrofit with ESFF
hardware) is calculated from the predicted values.
In the following sections instructions are given for program operation.
A thorough breakdown of the program structure and a list of program variables
are also given as an aid to future modifications.
5.1 SYSTEM REQUIREMENTS
The computer program (called PULSEJET) was developed for two different
types of microcomputers: the Tektronix series 4050 computers and the TRS80
Models I and III. For the PULSE-JET program to run successfully on a
Tektronix 4051, 4052, or 4054, the computer must have a minimum of 32 kilo-
bytes of available memory (RAM). Floppy disk drives are not required for
program operation. The program will provide hard copies of the program
input and output on a Tektronix Hard Copy Unit if it is available.
The minimum system required to run the TRS80 version of the program
includes a TRS-80 Model I or III microcomputer with 32 kilobytes of avail-
able memory and one 5-1/4-in floppy disk drive. The program requires
either the TRSDOS® or NEWDOS® Disk Operating System (DOS) or any other DOS
that is capable of running Microsoft Disk Basic and is file-compatible with
TRSDOS. The pulse-jet program is also designed to provide a listing of
results on a line printer (e.g., Radio Shack Line Printers VII or VIII).
It is desirable to have all of the computer equipment plugged into a single,
switched outlet strip so that everything can be turned on at once. If the
5-1
-------
computer has two or more disk drives, it is recommended that the PULSEJET
program be placed on a write-protected disk along with a DOS.
5.2 BACKGROUND INFORMATION
This chapter is not intended to introduce the reader to computers. It
is assumed that the reader knows how to operate the computer and to handle
tape cartridges properly (for Tektronix computers) and/or floppy diskettes
(for TRS-80 computers). Those not familiar with the proper methods for
computer operation should refer to the appropriate reference manual—either
the Graphics System Reference Manual for the Tektronix or the TRSDOS & DISK
BASIC Reference Manual for the TRS-80 computer.
There is very little system-specific information necessary to execute
PULSEJET on the Tektronix computers; however, the user should be familiar
with the keyboard and the AUTO LOAD button. The TRS-80 user should be
familiar with the BASIC, LOAD, and RUN commands.
Regardless of which computer is used, it is strongly recommended that
the reader make a spare copy of the PULSEJET program and store it in a safe
place. This is protection in the event that the original copy of the
program is lost or destroyed.
The PULSEJET program is just a tool, and, as with any tool, the best
way to become familiar with it is to use it; but a brief look at the program
structure is first in order. Figure 5-1 is a simplified flow chart of the
PULSEJET program. The program begins by assigning default values to program
variables and setting up character strings. The first input item called
for by the program is the date. This will be used to help document the
results. Next the user is given the opportunity to select English or
metric units for the program parameters. Of course the results are unaf-
fected by this choice; it is simply an option to allow the program operator
a choice of units for entering program parameters. It should be noted that
once a set of units has been chosen, all affected parameters will be in
those units and the only way to switch to the other set of units is by
restarting the program.
After the system of units has been specified, the program prints the
Main Menu. This menu is the heart of the program as well as its key to
flexibility and ease of use. The Main Menu presents eight options that
5-2
-------
START \
Initialize Strings ]
and Parameters I
Input:
English or Metric Units?
1. Enter Plant Data
2. Enter Baghouse Data
3. Estimate PULSEJET Performance
4. Calculate Costs for a New Baghouse
5. Calculate Costs for an ESFF Retrofit
6. Change Cost Adjustment Factors
7. HELP
8. END
Input:
Choose Menu Option
Go to Subroutine
According to Option N
Print Cost Factor Menu
1. Inst and Controls
2. Taxes
Camp. ESFF Capital
and O&M
Comp. non-ESFF O&M
Compute Capital,
O&M, and NPV
Return to Main Menu
JInput: Enter
Jo. (MO) of
rent, to Change
7. Maximum Pressure
Is
ntered No. in
MO) Range
Input:
Enter New Value
Entered No. in
1-7) Ran
Loop Back to
Cost Factor Menu
Input:
Enter New Value
Input:
Enter New Value
Input:
Enter New Value
Perform. Model Menu
Baghouse Data Menu
Compute K2 or
AP__andAP
nput: Does Plant
Have FGD System?
Return to Model Menu
Figure 5-1. Program flow chart.
5-3
-------
can be exercised by the user. When an option is chosen, the program exe-
cutes one or more subroutines that may also contain menues and returns to
the Main Menu when that option has been completed. For example, option
number seven is the HELP routine. When the operator chooses this option,
the program will print a summary of instructions on how to use the program.
When the instructions have been read, the program wil-1 return to the Main
Menu. There is no limit on the number of times an option can be called.
Similarly, there are no restrictions on the order in which options can be
called.
The menu format of the PULSEJET'program makes it very easy to use.
The program can be mastered by anyone, regardless of prior experience with
computers. In the next section, step-by-step instructions on how to operate
the program to evaluate a proposed ESFF baghouse will be given.
5.3 SAMPLE SESSION OF PULSEJET EXECUTION
The instructions that follow applies to both the Tektronix and the
TRS-80 computers. Program execution is virtually identical for each machine;
however, the differences will be explained fully.
On the Tektronix computer, turn on the power, insert the tape cartridge,
and press the AUTO LOAD button on the keyboard. The PULSEJET program will
be loaded from the tape and execution will begin. (It has been assumed
here that PULSEJET is the first file on the tape.) From DISK BASIC on the
TRS-80 type RUN"PULSEJET/BAS." The program will be loaded from the floppy
disk and execution will begin. The first thing the program does is print a
heading on the screen as shown in Figure 5-2. There may be a slight pause
while the program initializes variables and strings, but soon the program
will ask for the date. The program is expecting a character string, so any
format can be used (e.g., 10/31/82 or Oct. 31, '82, etc.). Immediately
after the date has been entered, the program will give the user the opportun-
ity to specify English or metric units. For this example, press either E
or e and RETURN.
Immediately after the system of units has been chosen, the screen will
clear and the Main Menu will be written as shown in Figure 5-3. As a
simple demonstration of the menu approach to program execution, choose the
5-4
-------
Pulse Jet Cost and Performance Models
***X*tt*
DATE : 1x11x83
DO YOU WANT ENGLISH OR METRIC UNITS e
Figure 5-2. At the beginning of the PULSEJET program, a heading is printed and
then there is a pause while some variables are initialized. The date is the
first item requested. It can be entered in any format.
5-5
-------
Pulse Jet Cost and Performance Models - Main Menu
i. Enter Plant Data
2. Enter Baghouse Data
3. Estinate Pulse Jet Perfornance
4. Calculate Costs for a Hew Baghouse
5. Calculate Costs for ESFF retrofit
6. Change Cost fid just Men t Factors
7. HELP
8. END
Uhich option uould you like to run Cl-S)
Figure 5-3. The main menu of the PULSE JET program presents the user with 8 options.
5-6
-------
HELP option by typing the number 7, followed by RETURN. The screen will
clear and the message shown in Figure 5-4 will be printed on the screen.
Press any key, except SHIFT, followed by RETURN to return to the Main Menu.
The program returns to the Main Menu and waits for selection of another
option.
Now consider the following scenario: A new boiler with attendant
pollution controls is to be installed in a plant. There is already one
boiler operating at this plant and a pulse-jet baghouse is used for particu-
late control. The new boiler is identical to the existing one so it can be
assumed that the gas flow rate and emissions from the boiler will also be
the same. The PULSEJET program can help determine whether or not an ESFF
baghouse offers any advantages over a conventional pulse-jet baghouse for
the new boiler.
One of the required steps for estimating the cost is to specify the
plant parameters. From the Main Menu choose option number 1 by pressing
the number 1 followed by the RETURN key. The program will clear the screen
and ask for the Plant Name. Enter any name that will identify this plant
and press RETURN. The Plant Data Menu will then appear on the screen as
shown in Figure 5-5a for the Tektronix computers. Figure 5-5b shows the
equivalent screen display for the TRS-80. This menu contains parameters
that determine the size of the boiler, the amount of emissions from the
boiler, current cost escalation factors, and the current discount rate.
The numbers listed in the far left column on the display are for identifica-
tion of the parameter described in that row. The numbers in the far right
column are the values currently assigned to the parameter. When this menu
is displayed for the first time, the default values for those parameters
are shown. The default values are there simply for convenience. If the
default value is adequate, there is no need to change it. They also serve
to fill in the gaps where values are unknown. Thus, the default value of
item number 1 (Boiler Size) is 3.4 MBtu/h. For this case study, assume
that the boiler size will be 5.0 MBtu/h. Therefore, the value listed on
the screen must be changed. To do this, press 1 to identify item number 1
and RETURN. The current value of Boiler Size will be printed along with
the question "New value?" (see Figure 5-6). Enter 5.0 and press RETURN.
5-7
-------
********** HELP
The screen which you just saw listed eight options
which are available to you. To execute any one of these
options press a number between 1 and 8 followed by the
RETURN key. The program will execute the. sutaroutine
uhich corresponds to that option number.- When that routine
has been completed the program will return to the Main
Menu. The order in uhich the options are selected does not
matter. You can execute any of the subroutines any nuwber
of tines.
The data input options <1 and 2> and the Performance
Modeling option also present .you with menus. In these menus
you are presented with a list of parameters and their
values. To change one of the values* enter its ID number
Cthe number in the left-hand column) followed by RETURN.
Enter the neu value for theft parameter .fol lowed by RETURN.
The screen will be rewritten with the neu value.
For complete instructions consult the PULSEJET users
documentation.
Press RETURN to continue
Figure 5-4. A brief description of how to run the program is printed
on the screen when the operator chooses the HELP option.
5-3
-------
Da.ta for Plant denol
1 Boiler Size.
2 Capacity Factor
3 Chen. Eng. Plant Cost Index
4 Emission Limit
5 Plant Al titude
6 Effective Annual Discount Rate
7 Cost of Electricity
8 Contingency as Percent of Field Cost
9 Engineering as Percent of Field Cost
10 Stean Cycle Efficiency
11 Gas Flow Rate
12 Boiler Enissions
13 Coal Heating Value
14 Fraction Excess Air
15 Percent Carbon in Coal
16 Percent Hydrogen in Coal
17 Percent Oxygen in Coal
13 Percent Sulfur in Coal
19 Percent Nitrogen in Coal
20 Percent Ash in Coal
21 Percent Water in Coal
3.41
70.0
270.0
3.1
0
10.00
30.00
20.0
20.0
85.0
0
0.0
9993
0.25
60.00
MBtu/hr
IbxMBtu
ft
Mil/kuh
JC
*
•;
Kacfn
IbxMBtu
Btu/lb
5.
11
40
20
0.60 ':
1.60 '-:
7.60 ':
13.60 *
Enter the nuwber of the iten you uant to change or enter
* to exit from this routine
Figure 5-5a. Plant data menu showing default values for each parameter
(Tektronix version).
5-9
-------
Data for Plant demol Page 1 of £
fr*******W********-* •*****•»
1 Boiler Size
£ Capacity Factor
3 Chem. Eng. Plant Cost Index
4 Emission Limit
5 Plant Altitude
S Effective Annual Discount Rate
7 Cost of Electricity
8 Contingency as Percent of Field Cost
3 Engineering as Percent of Field Cost
10 Steam Cycle Efficiency
Enter the number of the item you want to change;
to the next page; or * to exit from this routine
MBtu/hr
i3. 1
0
1
30. 0U
£0. 0
£0.0
as. 0
inge;
Ib/Mbtu
ft
) Jt/yr
) mil/kwh
•/.
•/.
•/-
> to go
Figure 5-5b. In the TRS-80 version of the program the plant data menu
is divided into two "pages".
5-10
-------
Data -for Plant- denol
Boiler Size
2 Capacity Factor
3 Chen. Eng. Plant Cost Index
4 Enission Linit
5 Plant Altitude
6 Effective Annual Discount Rate
7 Cost of Electricity
8 Contingency as Percent of Field Cost
9 Engineer ins as Percent of Field Cost
18 Stean Cycle Efficiency
11 Gas Flow Rate
12 Boiler Emissions
13 Coal Heating Value
14 Fraction Excess Air
15 Percent Carbon in Coal
16 Percent Hydrogen in Coal
17 Percent Oxygen in Coal
18 Percent Sulfur in Coal
19 Percent Nitrogen in Coal
28 Percent Ash in Coal
21 Percent Hater in Coal
1
3.41
70.9
279.8
8
9
19.99
39.98
20.9
29.8
85.0
8
9.8
3993
9.25
68.89
5.48
11.29
8.68
1.68
7.68
13.68
MBtu/hr
Ita/MBtu
ft
/yr
'/.
'/.
Kacfn
Btuxib
'/.
*•
'/.
Enter the nunber of the iten you want to change or enter
* to exit froM this routine 1
Boiler Size
3.41 Hew value =
Figure 5-6. A value is changed by specifying the corresponding item number
(1-21). The program prints the current value and asks the user
for the new value.
5-11
-------
The screen will clear and the Plant Data Menu will be rewritten with the
new value for Boiler Size while the other values remain unchanged. Thus,
to change any value, specify the parameter to be changed by its identifi-
cation number (1-21) and then enter the new value.
For the TRS-80 version of PULSEJET there are more plant parameters
than can fit on the screen at one time. For this reason, the Plant Data
Menu is split into two "pages". A page is simply a screen full of informa-
tion. When the Plant Data Menu is called, only the first 10 items of the
menu are displayed. To see the remaining 11 items, press the greater-than
symbol (>) and RETURN. To return to the first page of the menu, press the
less-than symbol (<) and RETURN. This is the only difference between the
two versions of the program in this option. The parameter values are
changed in the same manner as described above.
One other point about the Plant Data Menu concerns the gas flow rate
and boiler emissions option. These are listed as items number 11 and 12 in
the Plant Data Menu. The default values for these parameters are both
zero, since it is assumed that they are to be calculated from the coal
analysis (items 13-21). For this case study, since the new boiler is
identical to the existing boiler whose gas flow rate is known, the gas flow
rate can be entered; likewise for the boiler emissions. Enter a value of
10 k acfm (i.e., 10,000 acfm) for item 11 and 100 Ib/MBtu for the boiler
emissions (item 12).
When all of the proper values have been entered into the Plant Data
Menu, press the asterisk key (*) followed by RETURN. The program will do
some calculations and then ask if an FGD system is included with the plant.
For this example, answer N and press RETURN. This completes the Plant Data
Input option. The Main Menu will be redisplayed on the screen.
The next step in estimating the cost of an ESFF baghouse is to predict
its performance. This can be done with the aid of option number 3 of the
PULSEJET program. Select option 3 from the Main Menu. The display should
appear as in Figure 5-7. Each of the first four values listed must be
specified. That is, the user must enter a nonzero value or leave the
default value unchanged. Of the last three values, at least one must be
entered. Note that the maximum pressure drop in the filtering/cleaning
5-12
-------
Pulse Jet Perforwance Model
1 Residual Pressure Drop
2 Inlet Dust Concentration
3 Tine between Cleaning Cycles
4 Air to Cloth Ratio
5 Applied Field
6 Specific Resistance Coefficient
7 Max i HUM Pressure Drop
1.57 in H20
8.31 Ib/ft3
1.888 nin
2.87 t't/Hin
8.88 KU
8.8 in H20
Enter the nunber of the iten you want to change or enter
* to perforn calculations or enter ** to exit froii this
subroutine.
Figure 5-7. Input menu for the PULSEJET performance model.
5-13
-------
cycle (item number 7) is required only when K2 is unknown, in which case K2
is calculated as shown in Table 2-1. The user can specify an ESFF baghouse
by entering a positive value for the Applied Field, or specify a conventional
baghouse by leaving this value at zero.
For this case study, assume that items 1, 2, 3, 4, and 7 are known for
the conventional baghouse. Assume that the default values for items 1
through 4 as shown in Figure 5-7 are the correct values for this plant, but
that the K2 is unknown. Enter a value of 10.0 in. H20 for the maximum
pressure drop. Notice that when a value is entered for item 7, the value
of K2 is automatically set to zero by the program. Now begin the computation
by pressing * and RETURN. The program will compute K2 and display the
result as shown in Figure 5-8. At this time the user has the option of
printing the results or continuing computation. In either case the program
redisplays the menu with the computed value of K2 inserted and the value of
maximum pressure drop set to zero.
Now that K2 has been determined, an ESFF performance can be estimated.
As noted earlier, the optimum value of applied field for ESFF performance
is between 2.5 and 3.0 kV. Assume a value of 2.75 kV and enter that value
for item 5 in the menu.
Now compute the maximum pressure drop for an ESFF baghouse by pressing
* and RETURN. Note that the resulting value is significantly lower than
the maximum pressure drop of the conventional baghouse. This indicates a
potential savings in operating costs for an ESFF baghouse compared to a
conventional baghouse. To determine whether or not this is true, return to
the Main Menu by pressing ** followed by RETURN.
Before the capital and operating costs can be calculated, some prelimi-
nary information about the baghouse must be entered into the program. From
the Main Menu choose menu option 2. The menu shown in Figure 5-9 will
appear on the screen. Assume that the default value for Gas Temperature is
adequate as well as the Expected Baghouse Life. Notice that the program
has carried over the values of Air-to-Cloth Ratio and Applied Field from
the performance modelling subroutine. Also, the average pressure drop as
computed by the modelling subroutine has been entered here, so these values
do not need to be changed. The remaining inputs (5 through 12) affect the
5-14
-------
tn
i
en
Pulse Jet Perfornance Model
1 Residual Pressure Drop
2 Inlet Dust Concentration
3 Tine between Cleaning Cycles
4 Air to Cloth Ratio
5 Applied Field
6 Specific Resistance Coefficient
7 Maxinun Pressure Drop
1.97 in H20
0.31 Ib/ft3
1.000 nin
2.07 ft/win
0.00 KU
0.00 dP/UW
10.0 in H20
Enter the number of the iten you want to change or enter
t to perforn calculations or enter ** to exit fron this
subroutine.*
Conventional Pulse Jet Filter
Specific Resistance Coefficient = 6.03 dP/UW
Do you uant a hardcopy y
Figure 5-8. The program will compute K2 based on APr and APmax (units of K2 are inches H2O ft • min/lb).
-------
FABRIC FILTER COST INPUT
1 Gas Temperature 362 F
2 Expected Baghouse Life 29 yrs
3 Air to Cloth Ratio 2.074 ft/win
4 Average Pressure Drop 1.89 in H20
5 Applied Field 2.75 KU
6 Cost of Fabric 4.65 *x«2
7 Bag Life 4.8 yrs
8 Labor Rate $14.88 /hr
9 Material Overhead Fraction 8.190
19 Fan Load Factor 8.889
11 Scheduled Bag Replacement Tine 3 nin/ft2
12 Unscheduled Bag Replacement Tine 1 ninxft2
Enter the nuaber of the i ten you want to change or enter
* to exit fron this routine
Figure 5-9. Input menu for baghouse design, operating, and cost data.
5-16
-------
operating cost of the plant. Assume that all of these values are adequate
but remember that they can be changed if necessary. Since no changes are
needed from any of the menu parameters, return to the Main Menu by pressing
* and RETURN.
Now the cost of a new ESFF baghouse can be computed by selecting
option 4. When this routine is executed, the screen will clear and the
results of the cost calculations will be presented as shown in Figure 5-10.
The program lists all of the capital and operating costs as well as the Net
Present Value of the baghouse. To compare this cost to that of a conven-
tional pulse-jet filter, generate another set of costs. To do this, return
to the Main Menu and execute Option 2 again. Change the average pressure
drop to the value that was calculated above in the model routine for the
conventional pulse jet case and set the value of Applied Field to 0 kV.
Return to the Main Menu once again and exercise Option 4. The program will
now compute the capital, operating, and NPV costs for a conventional filter.
Note that when the Applied Field is 0 kV, the cost of ESFF hardware shown
in the printout is 0.
This concludes the demonstration of how to use the PULSEJET program to
estimate the performance and cost of both a conventional and an ESFF bag-
house. All of the parameters necessary to estimate the cost can be entered
via Options 1 and 2. Alternatively, if modelling calculations are necessary,
the program will compute the design parameters necessary for cost estimation.
In the case of an ESFF retrofit to an existing baghouse, the procedure
is similar, but a brief description is in order. The object of an ESFF
retrofit is to reduce the pressure drop across the baghouse while maintain-
ing the same air-to-cloth ratio, thereby reducing the cost of running the
induced draft fan. Therefore, to evaluate the benefit of an ESFF retrofit,
the reduction in pressure drop must be known. This can be determined with
the aid of the Pulse-Jet Performance Model, Main Menu Option 3.
For example, assume that the manager of the hypothetical plant discussed
earlier wants to evaluate the economic feasibility of retrofitting the
existing, conventional baghouse with ESFF. Recall that the new ESFF baghouse
considered above operates at the same air-to-cloth ratio as the existing,
conventional baghouse but with a lower pressure drop. By retrofitting the
5-17
-------
FABRIC'FILTER COST SUMMARY
CoMector % Supports-
ESFF Hardware
Ducting & Supports
Ash Rsnoval Systen
Insul ation
Ash Pond
ID Fan
Mi seel laneous
To^al Field Cost.
Engineering
Contingency
Operating Labor
Maintenance Labor and Materials
Cost of Electricity
Annual Cost of Bags and Cages
Net Present Ualue
$
*
$
$
$
$
8.96E+094
4.D5E+003
3.97E+003
8.08E+004
1 . 93E+094
1.32E+Q04
3.05E+003
2.23E+005
5.96E+004
3.36E+004
5.32E+S04
4.88E+004
1.74E+083
1.01E+804
* 4.43E+985
* 5.32E+035
* 1.31E+88S
Do you want a hardcopy y
Figure 5-10. The PULSEJET program prints a list of capital cost items, operating
cost items, and net present value for new baghouses.
5-18
-------
existing baghouse with ESFF, the two baghouses should perform identically.
Therefore, to determine the cost of the ESFF retrofit, use the Baghouse
Data Entry subroutine (Main Menu Option 3) to specify the expected average
pressure drop, air-to-cloth ratio, and applied field. Return to the Main
Menu and exercise Option 5. As with Main Menu Option 4, there is no input
required in-this subroutine; the results are calculated and printed on the
screen, as in Figure 5-11.
To review the use of the retrofit cost routine, use the performance
model or data from an existing pulse-jet ESFF baghouse to determine the
air-to-cloth ratio, average pressure drop, and applied field. Enter these
parameters into the Baghouse Data Entry subroutine and call Main Menu
Option 5. In this sense Options 4 and 5 from the Main Menu are the same.
One last item to note about the Main Menu is Option number 6; "Change
Cost Adjustment Factors." This routine is for specifying the adjustments
to costs as described in Section 4.3. The menu for this routine is shown
in Figure 5-12 and its operation is identical to the operation of Main Menu
Options 1 and 2.
5-19
-------
ESFF Retrofit Cost Analysis
+ -H"f+++"f++-H"f++++-M"H
Collector 8t Supports
ESFF Hardware
ducting i Supports-
Ash Renoval Systerr
Insulation
Ash Pond
ID Fan
Miseel 1aneous
Total Field Cost.
Engineering
Contingency
Turn-key Cost
Operating Labor
Maintenance Labor and Materials
$ 3.
$ 4.
$ Q.
$ 0.
$ 0.
$ 0.
$ 0.
80E+063
65E-t-0Q3
Q0E+000
00E+000
00E+000
00EH-000
Q0E-t-000
95E+003
$ 5.
$ 1.
49E+082
92E+003
,$ 9.68E+003
1.21E+804
$ 0.00E+0U0
Atvnaal Operating Cost Savings * 4.77E+QQ1
Savings/Investment Ratio : 8.Q35
Warning : Payback Period cannot be cowputed
Do you want a hardcopy y
Figure 5-11. The printout for a retrofit cost analysis includes the capital cost of
ESFF hardware, the annual savings in operating cost, the savings/
investment ratio, and the payback period.
5-20
-------
Cost Adjustnettt Factors Input
1 Instruments & Controls 1.00
2 Taxes 1.00
3 Freight 1.00
4 Erection & Handling 1.00
5 Site Preparation 1.00
6 Facilities & Buildings 1.00
7 Engineering & Supervision 1.00
8 Construction & Field Expenses 1.03
9 Construction & Fee 1.00
10 Contingencies 1.00
Enter the nunber of the iten you want to change or enter
t to exit fron this routine
Figure 5-12. The cost adjustment factors can be changed to reflect the complexity
or simplicity of equipment installation.
5-21
-------
6. REFERENCES
VanOsdell, D. , M. B. Ranade, G. P. Greiner, and D. F. Furlong, Elec-
trostatic Augmentation of Fabric Filtration: Pulse-Jet Pilot Unit
1.
trostatic Augmentation .. .__.._
Experience," EPA-600/7-82-062, U.S. Environmental Protection Agency.
Research Triangle Park, NC, October 1982.
2. Leith, D., and M. J. Ellenbecker, "Theory for Penetration in a Pulse-Jet
Cleaned Fabric Filter," J.A.P.C.A.. 24 (No. 8) (1980) 877.
3. Dennis, R., "Collection Efficiency as a Function of Particle Size,
Shape, and Density: Theory and Experience," J.A.P.C.A., 24 (1974)
1156.
4. Lamb, G., and P. A. Constanza, "A Low-Energy Electrified Filter System,"
Flit, and Sep.. July-August 1980, 319.
5. Billings, C. E., and J. Wilder, Handbook of Fabric Filter Technology,
National Technical Information Service Publication Number PB-200648,
Springfield, VA, 1970.
6. Dennis, R., and H. A. Klemm, "Modeling Concepts for Pulse-Jet Filtra-
tion," J.A.P.C.A.. 30 (No. 1) (1980) 38.
7. Dennis, R., J. E. Wilder, and D. L. Harmon, "Predicting Pressure Loss
for Pulse-Jet Filters," J.A.P.C.A.. 31 (No. 9) (1981) 987.
8. Uhl, V. W., A Standard Procedure for Cost Analysis of Pollution Con-
trol Operations; Volume I. Volume II. EPA-6QO/8-79-Q18a and b, U.S.
Environmental Protection Agency, June 1979.
9. U.S. Deptartment of the Navy, Economic Analysis Handbook, Article No.
14815, NAVFAC P-442, July 1980.
10. Kinkley, M. L., and R. B. Neveril, Capital and Operating Costs of
Selected Air Pollution Control Systems. EPA-450/5-8Q-Q02 (NTIS PB8Q-
157282), May 1976.
11. Viner, A. S. , and D. S. Ensor, Computer Programs for Estimating the
Cost of Particulate Control Equipment, Research Triangle Institute,
prepared for U.S. Environmental Protection Agency, Industrial Environ-
mental Research Laboratory, Research Triangle Park, NC 27711, February
1982.
6-1
-------
12. Ponder, T. C., Jr., et al. Simplified Procedures for Estimating Flue
Gas Desulfurization System Costs. EPA-600/2-76-150 (NTIS PB-255978),
May 1976.
13. Dennis, R., and L. Silverman, "Fabric Filter Cleaning by Intermittent
Reverse Air Pulse," ASHRAE J.. 4 (No. 3) (1962) 43.
14. Leith, D., and M. W. First, "Pressure Drop in a Pulse-Jet Fabric
Filter," Filt. and Sep.. Sept.-Oct. 1977, 473.
15. Leith, D. , and M. J. Ellenbecker, "Theory for Pressure Drop in a
Pulse-Jet Cleaned Fabric Filter," Atm. Env. . 14 (1980) 845.
6-2
-------
APPENDIX A
CONVENTIONAL PULSE-JET MODELS
A-l
-------
APPENDIX A
CONVENTIONAL PULSE-JET MODELS
Because of the difficulties of using data from different sources taken
under widely different conditions and with very different equipment, it is
not possible to apply a single model to predict the pressure drop in a
conventional pulse-jet filter. The purpose of this section is to describe
the models presented in the literature in order to show what factors are
expected to be of importance in conventional pulse- jet filters.
The two empirical models for pressure drop in pulse- jet filters illus-
trate qualitative effects. Dennis and Silverman1 find that the average
pressure drop for constant velocity filtration is primarily affected by the
reservoir pressure, the inlet loading concentration, and the filtration
time. Leith and First2 found that reservoir pressure, filter loading, and
face velocity are the major parameters affecting the maximum pressure drop
across the filter. They found that the velocity raised to the 2.5 power
had a strong affect on the pressure drop. The dependence on the reservoir
pressure was P. and P. by Dennis and Silverman, and Leith and First,
respectively. Thus reservoir pressure was first found empirically to have
an important effect on the pressure drop.
As previously discussed, Dennis et al.3 4 attempted to theoretically
predict P in terms of system variables. Using a combination of theoretical
and empirical equations they found that the pressure rise time affects the
effective residual pressure drop quite significantly. To relate the rise
time to normally measured operating variables, they found
d(P)/dt =
and empirically correlating their data they show
Pe = 615V(d(P)/dt)"1'13 (A-2)
A-2
-------
TABLE A-l. MAJOR ASSUMPTIONS OF THE MODELS
Dennis and coworkers3 4
100 percent cleaning
Distinguishes between cake structure of redeposited dust and
freshly deposited dust
Rise time important variable
Empirical correlation of rise time with reservoir pressure
Leith and Ellenbecker3
Cleaning efficiency a function of pressure drop
No difference between cake structure of redeposited dust and
freshly deposited dust
Reverse pressure drop important variable
Empirical correlation of static pressure with reservoir pressure
TABLE A-2. HOW TO TEST MODELS
Dennis and coworkers3 4
Correlate (P ) with dP/dt
Test dP/dt «P.
J
Variables needed:
(PE), PJ, d(P)/dt, Ajl Tj, Pb, Vb, pb, WQ, V, W, P
Leith and Ellenbecker5
Test a a (p - p)
Correlate P<- with P.
^ J
Variables needed:
Ps> P.. P. s. a, p, WQ> V. W.. Pr
A-3
-------
where
P. = pulse reservoir pressure
v
A. = nozzle cross-sectional area
J
T. = absolute cleaning gas temperature
J
P. = bag maximum static pressure
V. = maximum bag volume
p. = gas density
d(P)/dt = rise time during cleaning pulse.
The constant k was experimentally developed for coal fly ash filtered with
wool and polyester felts. This expression has not been tested widely
either for the system for which it was derived or for other systems.
Leith and Ellenbecker5 take a very different approach in developing a
pressure drop model for conventional fabric filters. This approach may be
of use in the future when more data have been found for the unknown param-
eters that they postulate in their model.
They assume a general expression similar to Equations 3 and 4 in
Chapter 2
P = K! V + K2 VW . (A-3)
However, they assume that the loading on the filter, W, is not equal to the
dust that enters the filter, W0 = C^Vt. They attempt to account for the
fabric cleaning by defining e as the fraction of the inlet dust that is
removed from the filter and deposited in the hopper by each cleaning pulse.
Therefore at steady state
W = W0/e . (A-4)
Furthermore to account for the dust that is redeposited on the filter after
the cleaning pulse has finished they use
e = a • p (A-5)
A-4
-------
where a is the total fraction of inlet dust that is removed from the filter
fabric by the cleaning pulse and p is the fraction of the removed dust a
that falls to the hopper and is consequently removed from the system. They
postulate that the fraction a is proportional to the applied removal force
and that the removal force is given in terms of a reverse pressure drop.
They define the reverse pressure drop as
PR = (PS-P) (A-6)
where P is the maximum static pressure supplied to the bag by the cleaning
pulse. Thus, they postulate
a = K3(PS- P)-K4 (A-7)
Combining equations A-3, A-4, and A-7 one can solve the resulting
quadratic equation for P to give
(P -K4/K-5+M) V(P -IQ/K-rlW - 4(W/fJ)V(K2/K3)
5JU
Using limited data for their system they find that P is given by
(A-9)
Thus, reservoir pressure is important in this model because it is related
to the maximum static bag pressure, and the bag static pressure is in turn
related to the force that removes the dust. However, in order to use this
model it is necessary to have data to evaluate the constants Kj, K2, K3,
and K4. Leith and Ellenbecker6 assume that Kx can be taken from the clean
fabric, although the residual drag would be more appropriate, and that the
ratio K4/K3 is negligible. Thus a set of data is needed to find the ratio
K2/K3 and the constant p in order to apply this model. This model has not
been generally tested and thus it is not recommended for use at the present
time.
Table A-l lists the assumptions made in the two different studies.
Table A-2 lists the critical variables and equations that need to be measured
and tested to improve and validate the models.
A-5
-------
REFERENCES
1. Dennis, R., and L. Silverman, "Fabric Filter Cleaning by Intermittent
Reverse Air Pulse," ASHRAE J.. 4 (No. 3) (1962) 43.
2. Leith, D., and M. W. First, "Pressure Drop in a Pulse-Jet Fabric
Filter," Filt. and Sep. . Sept..-Oct. 1977, 473.
3. Dennis, R. , and H. A. Klemm, "Modeling Concepts for Pulse-Jet Filtra-
tion," J.A.P.C.A.. 30 (No. 1) (1980) 38.
4. Dennis, R., J. E. Wilder, and D. L. Harmon, "Predicting Pressure Loss
for Pulse-Jet Filters," J.A.P.C.A. . 31 (No. 9) (1981) 987.
5. Leith, D., and M. J. Ellenbecker, "Theory for Pressure Drop in a
Pulse-Jet Cleaned Fabric Filter," Atm. Env.. 14 (1980) 845.
A-6
-------
APPENDIX B
Complete Listing of the Tektronix Version
of the PULSEJET Program
B-l
-------
REM-**** ESFF Pulse Jet Cost/PerforroQTice Models ****
110 REM Versiop 1.0 by A. S. Viner 1 Nov. 1982
120 J$=M*#***#;U##:**#****#M^
130 DIM CK21>,C2a4>,C3<7>,P<21>,R<20>,F<13>,Za6>,A<10>,MK7>
140 DIM U$<4>,E$<20>,0*<20>,G$<2>
150 HOME
160 PAGE
170 GOSUB 2110
180 GOSUB 2610
190 GOSUB 3200
200 GOSUB 3260
210 GOSUB 3500
220 GOSUB 3850
230 GOSUB 3900
240 GOSUB 4170
250 GOSUB 4220
260 PRINT " DATE : ";
^ 270 INPUT E$
280 FOR 1=1 TO 16
290 Z=0
360 NEXT I
310 H=0
326 0*=" "
330 PRINT
340 PRINT "DO YOU WANT ENGLISH OR METRIC UNITS u;
350 INPUT X*
360 U$=X$
370 IF POS(MEeMfi",U$,l)=0 THEN 340
380 HOME
398 PAGE
400 PRINT
418 PRINT
420 PRINT
436 GOSUB 2110
-------
DO
CO
446
450
460
4?0
480
490
500
510
520
530
540
550
560
570
580
590
600
616
620
630
640
650
669
670
680
690
700
710
728
730
746
750
760
770
786
PRINT
PRINT "
PRINT
PRINT "
PRINT
PRINT "
PRINT
PRINT "
PRINT
PRINT "
PRINT
PRINT "
PRINT
PRINT M
PRINT
PRINT "
PRINT
PRINT
PRINT
PRINT "
1. Enter Plant Data"
2. Enter Baghouse Data"
3. Estimate Pulse Jet Performance11
4. Calculate Costs for a New Ba«jhouse"
5. Calculate Costs for ESFF retrofit"
6. Change Cost Adjustment Factors"
7. HELP"
8. END"
Which option would you like to run
M •
INPUT 01
IF OKI OR 01 >8 THEN 380
GOSUB 01 OF 690,1070,5110,4450,6100,1380,2316,680
GO TO 380
END
REM PLANT INPUT ROUTINE
IF U$O"E" AND U$O"e" THEN 720
GOSUB 1818
HOME
PAGE
PRINT
PRINT "Plant nane "j
INPUT
HOME
PAGE
-------
790 PRINT J*
S&a PRINT "Data lor'Plant "JO*
816 PRINT J$
820 FOR J=l TO 21
838 PRINT USING "2dxs":J
840 X$=SEG(P$, H-*54,54>
858 PRINT USING X$:P*7,7>
870 PRINT X$
880 NEXT J
830 GOSUB 2220
900 IF X$=U*M THEN 980
910 IF X<1 OR X>21 THEN 890
920 PRINT
930 X$=SEG*54,54>
940 PRINT USING X$:P(X);
7950 PRINT " New value = M;
^960 INPUT P
970 GO TO 770
980 GOSUB 6580
990 GOSUB 2150
1000 IF MO1 THEN 1020
1810 GOSUB 1810
1020 PRINT "DOES PLANT HAUE AN FGD SYSTEM FOR S02 CONTROL (Y OR N> u;
1030 INPUT X*
1040 G$=SEGCX$,1,1>
1856 GOSUB 5000
1060 RETURN
1070 IF U$O"E" AND U*O"e" THEN 1100
1080 GOSUB 1910
1090 F<:i> = CFCl)-«-40>*<9/5)-40
1100 HOME
1110 PAGE
1120 PRINT J*
1130 PRINT "FABRIC FILTER COST INPUT"
-------
1140.PRINT J*
1:150 .FOR JL«1 TO 12
1160 PRINT USING "2dxs":J
1170 X$:=SEGj
1190 X$=SEG*7,7>
1200 PRINT X$
1210 NEXT J
1220 GOSUB 2220
1230 IF X$=*"*H THEN 1310
1240 IF X<1 OR X>12 THEN 1220
1250 PRINT
1260 X$=SEG*56,56>
1270 PRINT USING X$:F(X>}
1280 PRINT M New value * ";
1290 INPUT F
1300 GO TO 1100
= +40>*<5/9>-40
1350 HK4>=F<3>
1360 MK5>=F<5>
1370 RETURN
1388 HOME
1390 PAGE
1400 PRINT J*
1410 PRINT "Cost Adjustnent Factors Input"
1420 PRINT J$
1430 FOR J=l TO 10
1446 PRINT USING "2dxsM:J
1450 X*=SEG
-------
1.490 ;IR X$="*H THEN 1570
1:500 IF X<1 OR X>10 THEN 1480
1510 PRINT
1520 X$=SEGCA$, 1-KX-1>*54,54>
1530 PRINT USING X$:AJ
1540 PRINT " New value * ",'
1550 INPUT A=0.8*P<20>*10000000/P<13>
1610 IF IHT=P(2)/100
1640 2<3>=760-0.026*P<5>*3.281
T 1660 2<5>=P(3)/230.6
01 1670 2<6)=0
1680 2(7)=100000/0.454*1/P<10)*P<1)/P<13>
1690 Z<6>=17.1*/12+Pa6>/4-PC17>/32+PC18>/32>*>
1788 Z<6>=2<6>*760/(760-0.026*P<5)*3.281)
1710 2<6>=ZC6>*Z<7>*0.3048t3
1728 Z<8>=0
1730 IF IHT*P<11>
1750
1768
1778 Z<11>=SF<6>*215/P<3)
1780 IF Z<8».0 THEN 1800
1798 Z<8>«Z<6>*<+273>/273>*-F<4>*10/13.6>/2C3>
1880 RETURN
1818 REM UNITS CONUERSIOH
1828 FOR J=l TO 21
1830 P»PO>*C1CJ>
-------
1840 C
1850 NEXT J
1860 IF M=l THEN 1890
1870 M-l
1880 RETURN
1890 M=0
1900 RETURN
1910 REM Units CONUERSION
1920 FOR J=l TO 13
1930 F=F*C2U>
1940 C2=1/C2
1950 NEXT J
1960 IF M=l THEN 1990
1970 M=l
1980 RETURN
1990 M=0
2006 RETURN
2010 REM Units Coriversion
2020 FOR J=l TO 7
2030 MHJ>=MKJ>*C3U>
2048 C3(J)=1/C3CJ)
2050 NEXT J
2860 IF H=l THEN 2090
2070 M=l
2086 RETURN
2090 t1=0
2180 RETURN
2119 PRINT J$
2120 PRINT "Pulse Jet Cost and Performance Models - Main Menu"
2136 PRINT J$
2140 RETURN
2150 REM DISPLAY PLANT NAME ON SCREEN
2166 HOME
2170 PAGE
2180 PRINT J*
-------
CD
I
00
2199
2200
2210
2220
2230
2240
2250
2260
2270
2280
2290
2300
2310
2320
2330
2340
2350
2360
2370
2380
2390
2400
2410
2420
2430
2440
2450
2460
2470
2480
2490
2508
2510
2520
2530
PRINT 'VPlant
PRINT J$
RETURN
PRINT
PRINT
PRINT
"J0$
"Enter the
"* to exit
INPUT X$
nunber of
fron this
the iten
routine '
you want to change or enter"
X1=ASCCX$)
IF XK48 OR Xl>57 THEN 2300
X=UALCX$>
RETURN
REM Instructions
HOME
PAGE
PRINT
PRINT "*****#**** HELP **********"
PRINT
PRINT " The screen which you just saw listed eight options"
PRINT "which are available to you. To execute any one of these "
"options press a nunber between 1 and 8 followed by the "
"RETURN key. The progran will execute the subroutine"
"which corresponds to that option nunber. When that routine"
"has been completed the progran will return to the Main "
"Menu. The order in which the options are selected does not"
"natter. You can execute any of the subroutines any nunbern
"of tines."
PRINT
PRINT
PRINT
PRINT
PRINT
PRINT
PRINT
PRINT
PRINT " The data input options <1
PRI "Modeling option also present you
and 2> and
with nenus
the Performance"
In these Menus"
PRINT "you are presented with a list of paraneters and their
PRINT "values. To change one of the values, enter its ID nunber "
PRINT "
-------
DO
I
2540
2550
2560
2570
2580
2596
2600
2610
2620
2630
2646
2650
2660
2670
2680
2690
2700
2710
2720
2730
2740
2750
2760
2770
2780
2790
2800
2810
2826
2830
2840
2850
2860
2870
2880
PRINT
PRINT " For complete instructions consult the PULSEJET users"
PRINT "documentation."
PRINT
PRINT "Press RETURN to continue "J
INPUT X$
RETURN
REM
REM PLANT DATA INITIALIZATION
REM
DIM P$<1512),C$<294>
p$—ii ii
FOR 1=1 TO 21
READ X$
NEXT
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
I
ii H
H II
II II
H U
II II
II U
II U
II II
a ii
II M
n n
II M
II H
H II
M M
H •»
n n
M U
H H
Boiler Size
Capacity Factor
Chen. Eng. Plant Cost Index
Emission Limit
Plant Altitude
Effective Annual Discount Rate
Cost of Electricity
Contingency as Percent of Field Cost
Engineering as Percent of Field Cost
Steam Cycle Efficiency
Gas Flow Rate
Boiler Emissions
Coal Heating Ualue
Fraction Excess Air
Percent Carbon in Coal
Percent Hydrogen in Coal
Percent Oxygen in Coal
Percent Sulfur in Coal
Percent Nitrogen in Coal
""3d.2dX S"
""2D.D S"
""4D.D Su
""5D.DXX Su
""4DXXXX S"
IIU2D.2DxS"
""2D.2DXS"
"M2D.DxxS"
""2D.DxxSM
Ma2D.DxxS"
""4DXXXX S"
""3D.DXX S"
""SdXXXX s"
l>HD.2DxS"
""2D.2DXS11
""2D.2DxS"
"M2D.2DxSM
""2D.2DxS"
""2D.2Dx3u
-------
2899 DATA '""'Percent Ash in Coal ""2D.2DxS"
2999 DATA """Percent Mater in Coal ""2D.2Dx3"
2910 FOR 1=1 TO 21
2920 C1=1
2930 NEXT I
2940 C1<1>=3.41
2950 Cl<4>=0.002326
2960 Cl<5>=3.281
2970 C1<11)=2.119
2980 C1C12>=0.232
2990 Cl<13>=8.43
3800 FOR 1=0 TO 1
3010 FOR J=l TO 21
3030 NEXT J
3040 NEXT I
3850
3060
3070 C$=MMJ/s "feB*
3888 C$=C$fcB$
3890 C$=C$feun3/J n /yr nil/kwh^ \ Y, acns
3100 C^=C^fenri3/J kJ/kg
3110 FOR 1=1 TO 7
3120 C£=C$feZ$
3130 NEXT I
3148 C$=C$2cHMBtu/hr Ib/MBtaft /yr nilxkwh':
3158 C$=C*&"* Ji Kacfn Ib/MBtuBtu/lb
3166 FOR 1=1 TO 7
3170 C$=C$fcZ$
3180 NEXT I
3198 RETURN
3288 FOR 1=1 TO 21
3216 READ P
3228 NEXT I
3238 DATA 1,70,310,43,8,16,30,20,20,85,0,8,23240,0.25,60,5.4,11.2,0.6
-------
oa
i
3240 DATA 1.6,7.6,13.6
3250 RETURN
3268 DIM R$<1224>
3270 R$="n
3280 FOR 1=1 TO 17
3290 READ X$
3300 R$=R$kX$
3310 NEXT I
3320 DATA """Collector & Supports
3330 DATA 'ESFF Hardware
3340 DATA "" "Dae ting & Supports
3350 DATA """Ash Renoval Systen
3360 DATA "" " Insul ation
3370 DATA """Ash Pond
3380 DATA """ID Fan
3390 DATA "" "Miscel laneous
3400 DATA """Total Field Cost
3410 DATA """Engineering
3420 DATA """Contingency
3430 DATA """Turn-key Cost....
3440 DATA """Operating Labor
3450 DATA "" "Maintenance Labor and Materials
3460 DATA """Cost of Electricity
3470 DATA """Annual Cost of Bags and Cages
3480 DATA """Net Present Ualue
3490 RETURN
3500 REM
3510 REM FABRIC FILTER DATA INITIALIZATION
3528 REM
3530 DIM F*C864>,D$<182>
3540 F$=M"
3550 FOR 1=1 TO 13
3560 READ X$
3570 F*=F*feX$
3580 NEXT I
$""2E
$""2E
$""2E
$""2E
$""2E
$""2E
$ M " 2E
$""2E
$" "2E
$""2E
$""2E
$""2E
$U"2E
$""2E
$MI12E
n
u
n
n
n
ii
u
u
u
u
u
u
II
II
II
$"n2E"
-------
ro
H-»
ro
3590 DATA """Gas Tenperature
3600 DATA """Expected Baghouse Life
3610 DATA """Air to Cloth Ratio
3620 DATA """Average Pressure Drop
3630 DATA """Applied Field
3640 DATA """Cost of Fabric
3650 DATA "'"'Bag Life
3660 DATA HM" Labor Rate
3670 DATA """Material Overhead Fraction
3680 DATA """Fan Load Factor
3690 DATA """Scheduled Bag Replacement Tine
3700 DATA """Unscheduled Bag Replacement Tine
3710 DATA """Fraction of Unscheduled Bag Replacements
3720 FOR 1=1 TO 13
3730 C2CI>=1
3740 NEXT I
3750 D$=" C yrs m/min en H20 KU $/m2 yrs
3760 D$=D$fe" min/n2 min/m2 "
3770 D$=D$S." F yrs ft/win in H20 KU $/ft2 "
3780 D$=D$8e" yrs /hr min/f t2nin/f t2
3790 C2<4>=0.3937
3860 C2(3>=3.281
3810 C2<6>=0.093
3820 C2(ll)=0.093
3836 C2<12>=0.093
3840 RETURN
3850 FOR 1=1 TO 13
3860 READ F(I)
3870 NEXT I
3880 DATA 150,20,0.632,7.5,0,56,4,14,0.1,0.8,2,7,0.05
3890 RETURN '
3900 REM
3910 REM Pulse Jet Model Initialization
3920 REM
3930 DIM M*<392>,W*<98>
""3DXXXX S"
""2DxxxxS"
""D.3D S"
""2D.2DXS"
w"2d.2dxs"
""2d.2dxs11
"°2D.DxxS"
$"M2D.2DxS'1
""D.3D S"
I1IID.3D Su
n"2DxxxxSn
lin2DxxxxS"
""D.3D S M
/hr
it
-------
C30
I
3940
3950
3960
3370
3980
3990
4Q00
4010
4020
4030
4640
4050
4060
4070
4080
4090
4100
4110
4120
4130
4148
4150
4168
4178
418(3
4196
4206
4218
4228
4230
4240
4250
4260
4270
4280
FOR 1*1 TO
READ X*
I
NEXT
DATA
DATA
DATA
DATA
DATA
DATA
DATA
FOR 1=1
C3CI>=1
NEXT I
C3<1>=0
C3<2>=0
C3C4>=3
C3<6>=5
C3C7)=0
W£=B en
"MMTine between
"""Air to Cloth
"""
RETURN
FOR 1=1
"""Residual Pressure Drop
Dust Concentration
Clean in 9 Cycles
Ratio
Applied Field
"""Specific Resistance Coefficient
"""Maxinun Pressure Drop
TO 7
3937
662
281
987
3937
H20
Ib/ft3 nin
TO 7
CK2>
""2D.2dXS"
"M2D.2dxS"
""2D.3D S"
""2D.2DXS"
""2d.2dxsu
"tt2d.2dxs"
MU2D.DxxS"
nin n/rain KM
ft/nin KU
Nnin/gn en H20
dP/UW in H20n
in H20"
READ Mid)
NEXT I
DATA 5,5,1,0.632,0,3,0
RETURN
REM
REM Cost Adjustment Factor
REM
DIM A$<540>
Initialization
FOR 1=1 TO 10
READ X*
-------
DO
I
4310
4320
4330
4340
4350
4360
4370
4380
4390
4400
4410
4420
4430
4440
4459
4460
4470
4480
4498
4580
4516
4520
4530
4540
4558
4568
4570
4588
4590
4600
4618
4620
4630
I
NEXT
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
FOR
AU> = 1
NEXT I
RETURN
REM
REM FABRIC
REM
GOSUB
"""Instruments & Controls
"""Taxes
"""Freiaht
"""Erection & Handling
"""Site Preparation
"""Facilities 8. Buildings
"""Engineering & Supervision
"""Construction & Field Expenses
"""Construction fe Fee
"""Contingencies
1=1 TO 10
110 D.2D
"" d.2d
"" d.2d
"" D.2D
110 D.2D
""D.2D
""D.2D
nu D.2D
"" D.2D
1111 D.2D
FILTER COST SUBROUTINE
1596
GOSUB 4970
Za4>=ZU2>/1.46
( 12X51 10>*4.49*2<12>t0. 835
5> + *1.752*Z<12>t0.9461
Za5>=Za5>-KZ<12»16722>*1.04*Za2>
IF F<5>=0 THEN 4600
100+64. 8*Z<8>+15.24*<-5. 77+1 77*1. 128*0. 3137*2<8>t0.5>
n
n
R<4>=69000*Z(5)
RC5>=<4910+25.8*Z(12»*Z<5)
-------
DO
I—1
cn
RC6)=P2*1-.395*1.2*P<3)/148.2
R<7>«
•!-6S0-.R(8>=0
•'570 FOR 1 = 1 TO 7
R<8>=R(8>+R
NEXT I
RC9>=R<8>
4690
4780
4720
4730
4740
4750
4760
4770
4790
4800
4310
4820
4830
4840
4858
4869
4870
4880
4390
4960
4910
4920
4930
4940
4950
4960
4970
4980
.R<10)=P<9>/10B*A<7)*Z<13>
RC12>=R(9)+R<18)+R<11)
Rf. 13>-8760/8*( 1 . 5+2. 4E-4.*Z< 12> >*1 . 8*1 . 334*F<8)
Ra4>=8760/8*<1.5+2.4E-4*Z(12»*1.8*l.UF<8>
= *8760*8.182*Z<8)*F<4)-f66.74*ZC15»*Z<2>*P<7>/10ea
R<15)=R(15)+8760*Z<14)*0.39x0.6*F(5>xl000*Z<2)*P(7>xl000
R<16)=(1+F<9))*F<6)*Z<15)/F<7)
R<17>=R<:9)+R<17>*/(LOG(l.l)*l.ltF(2»
HOME
PAGE
PRINT
PRINT "FABRIC FILTER COST SUMMARY"
PRINT K$
FOR 1=1 TO 17
XS=SEG<:R$,l-KI-i;>*52,52>
PRINT USING X$:RCI>
NEXT I '
GOSUB 6580
RETURN
REM
REM POND SIZE, POND COST SUBROUTINE
BEST AVAILABLE COPY
-------
REM
,UOO IF G$="Y" OR G*="y" THEN 5040
;.p,ill P3=0.0S267*ZC9>*Z<;2>
13028 P2=13648#P3t0.583
f.036 RETURN
5040 F1=0.7*Z<9>
J' 59 P3=0.08267#+FmZ<2>
r-n)6Q Pl=13648*P3t0.583
5070 F2=0.08267*F1*Z<2>
5980 F3=13648*F2T0.583
5G9G P2=Pi-F3
5100 RETURN
5119 REM
5129 REM Pulse Jet Performance Model Calculations
513D REM
5140 IF U$O"E" £ND U$One" THEN 5160
5150 GOSUB 2010
5160 H£=SEG
£ 5170 ^^ ~
5180 HOME
5190 PAGE
3280 PRIMT J$
5216 PRIMT "Pulse Jet Perfornance Model
5220 PRIMT J$
)236 FOR J=l TO 7
^2
5240 PRIHT USIHG "2dxs":J
5250
5260 PRIHT USIHG X$:MKJ>;
5270 X$=SEG(W$,H-M*49-KJ-1>*7,7>
5286 PRIHT X$
5290 HEXT J
5300 PRIHT
5310 PRIHT "Enter the nunber of the iten you want to change or enter"
5326 PRIHT " * to perform calculations or enter ** to exit fron this11
5330 PRIHT "subroutine."}
-------
INPUT X
D3
I
X1=ASC
IF XK48 OR Xl>57 THEN 5398
5418
5428
5438
5440
5450
5460
5470
5480
5496
5566
.8
IF X$<>"**" THEN 5458
IF M01 THEN 5428
GOSUB 2018
F<5>=M1<5>
RETURN
IF X$="*" THEN 5588
IF X<1 OR X>7 THEN 5388
PRINT
PRINT USING X*:MKX>J
PRINT " Hew value = MJ
INPUT rmx>
IF X<6 THEN 5188
IF X=7 THEN 5560
-JO
55580
5590
5699
5610
5-528
5636
5640
5658
5668
5670
5688
GO TO 5188
GO TO 5188
IF M1C5»8 THEN 5838
PRINT
PRINT "Conventional Pulse Jet Filter"
IF nK6)=0 THEN 5730
PRINT
PRINT USING """MaxinuH Pressure Drop = IIH2d.2dxs":Dl
PRINT
-------
-^ PRINT USING ' Average Pressure Drop » HII2d.2dxs":D2
o?'30- PRINT. H*
r.riQ GOSUB 6580
,:T2'3 GO TO 5188
"•730 K2-
>.< r
cr~»tr .-4
5760 F<4>==Z<16>*H/C2<4>
5780 PRINT
5790 PRINT USING """Specific Resistance Coefficient = ""2d.2dxs":K2
5890 PRINT 1$
5310 GOSUB 6580
5320 GO TO 5180
5830 PRINT
58<*-C PRINT "ESFF Pulse Jet Filter"
5S59 IF MK6>=0 THEN 6030
™ 5069
» 587S
5880
5S90
5910
5920
5930 PRINT
5940 PRINT USING """ESFF Residual Pressure Drop = "M2d.2dxs":Pl
5950 PRINT \\$
5960 PRINT USING M""ESFF Average Pressure Drop * ""2d.2dxs":P4
5970 PRINT H$
5980 PRINT USING MHItESFF Maxinun Pressure Drop = MW2d.2dxsll:P3
5990 PRINT H^
6300 PRINT USING niMIPressure Drop Ratio = "nd.3dll:P2
6010 GOSUB 6580
6920 GO TO 5180
6S30
-------
PRINT
Pr-iIHT- USING """Specific Resistance Coefficient = ""2d.2dxs":K2
C PRINT 1$
GO TO 5866
- 108 REM
"110 REM ESFF Retrofit Cost SUBROUTINE
G128 REM
6138 GOSUB 1598
140 Za2>=Z<8>*68/F<3>
M5G Z<14>=2<12>/1.46
C168 FOR 1=1 TO 17
C>179 R=R<9>-fR(8)
6298 r«12>
6390 R<15)
6316 Ra5>=R<15>£2<2>*P<7>/1008
BO=LOG<1+P<6)/100>
S1=RC15>*B1
6350 R<17)*S1/RC12)
6368 P4=0
6370 IF B8*R<12>/R(15»1 THEN 6390
6388
-------
KOMI
FfiGE
PRINT K$
PUNT "ESFF Retrofit Cost Analysis"
PRINT K$
FOR 1=1 TO 14
'.SO PRINT USING X$:R(I)
. '70 NEXT I
,-!30 PRINT
:x-S9 PRINT USING """Annual Operating Cost Savings $ MM2e":Ra5>
L5G6 PRINT USING """Savings/Inwcstnent Ratio : ull2d.3d":R=0 THEN 6590
5520 IF POS=0 THEN 6640
563G COPY
5546 RETURN
-------
APPENDIX C
Cost Estimates for Industrial Coal-Fired Boiler,
Pulse-Jet Baghouse Systems
C-l
-------
APPENDIX C
Cost Estimates for Industrial Coal-Fired Boiler,
Pulse-Jet Baghouse Systems
One of the tasks of this project was to verify the models used for
predicting capital costs. The lack of published data on these costs led to
the conclusion that cost quotes would have to be obtained. Mr. Gary Greiner
of ETS, Incorporated, of Roanoke, Virginia, is a veteran in the field of
industrial scale baghouse systems. Mr. Greiner was hired as a consultant
with the task of obtaining reliable estimates of capital costs for pulse-
jet baghouses. His report is included in the following pages.
C-2
-------
COST ESTIMATES FOR INDUSTRIAL COAL-FIRED BOILER.
PULSE-JET BAGHOUSE SYSTEMS
PURPOSE;
To provide cost estimates for pulse-jet baghouse systems applied to
industrial coal-fired boiler plants. Information to be used as check
against a model being developed at RTI.
REQUIRED OUTPUT;
2
Cost estimates in $/ft. cloth for three representative sizes of
systems.
APPROACH;
System sizes were chosen representative of small, medium and large boiler
plants; 55,000 ACFM, 180,000 ACFM and 350,000 ACFM were used.
Several vendors were contacted and interviewed to obtain: design G/C
ratios; module sizes available for this application; bag sizes being
used or proposed; and flange-to-flange hardware costs.
From these interviews and prior ETS data, the following information was
developed.
ASSUMPTIONS;
All systems are modular in design and capable of module isolation for
off-line cleaning.
Costs are for hardware components listed below. Engineering, installation,
system components outside the flange-to-flange baghouse are not included.
The ash handling system is not included, as this is seldom supplied by the
baghouse OEM and no good cost estimates were obtained.
C-3
-------
INCLUDED COMPONENTS;
- Module housings complete with pulse system
- Woven Glass bags and cages
- Inlet and outlet manifolds
- Inlet and outlet dampers
- Insulation and flashing
- Hopper heaters
- Baghouse controls
- Structural supports and access
C-4
-------
TYPICAL SYSTEM ARRANGEMENT & COST
SYSTEM ACFM
f Modules
Gross G/C
Net G/C
# Bags /Module
Bag Size
Cloth /Module
2
Total Gross Ft.
Total Net Ft.2
Cost $/Ft.2
55,000
4
4.0
5.2
190
6"0 x!2' Lg.
3500
13,750
10,500
$24
180,000
10
3.91
4.34
210
6"0 x!4' Lg.
4600
46,000
41,400
$20
350,000
14
3.96
4.63
210
6"0 x!9f Lg.
2
6300 ft.
88,200
75,600
$17
ADDITIONAL COMMENTS;
- This market continues to be very competitive and prices have not
increased over the past few years. If the market opens up, these
*
prices could Increase substantially.
- Specific job quotes will normally have a range of 2/1 if 5-7 quotes
•are obtained.
- 19' long bags are only being offered by a few OEM's, but they have
been the past leaders in this market.
- The cost VS size curve tends to be very flat once a module and bag size
are chosen since most hardware costs have a per bag relationship.
C-5
-------
TECHNICAL REPORT DATA
(Please read I/iiUnictions on the reverse before completing)
1. REPORT NO
EPA-600/8-84-016
2.
3. RECIPIENT'S ACCESSION- NO.
. TITLE AND SUBTITLE
Cost and Performance Models for Electrostatically
Stimulated Fabric Filtration
5. REPORT DATE
May 1984
6. PERFORMING ORGANIZATION CODE
. AUTHOR(S)
Andrew S. Viner and Bruce R. Locke
'8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Research Triangle Institute *
P. O. Box 12194
Research Triangle Park, North Carolina 27709
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-02-3170, Task 76
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Task Final; 7/82 - 1/83
14. SPONSORING AGENCY CODE
EPA/600/13
is. SUPPLEMENTARY NOTES IERL-RTP project officer is William B. Kuykendal, Mail Drop
61. 919/541-7865. Navy project officer is Don Rowe. (*) Funded by U. S. Naval Surface
Weapons Center, Dahlgren, VA, via interagency agreement.
is. ABSTRACT -phe report gives results of a survey of the literature on performance mo-
dels for pulse-cleaned fabric filters. Each model is evaluated for its ability to pre-
dict average pressure drop from pilot plant data. The best model is chosen and used,
in conjunction with pressure drop reduction data from an electrostatically stimulated
fabric filter (ESFF) pilot plant, to produce a model of ESFF performance. The accu-
racy of the models is limited by their primitive nature and the size of the pulse-jet
performance data base. Where the baghouse, dust, and fabric to be modeled are very
similar to the pilot plant from which the model was developed, the model should per-
form adequately for comparison between ESFF and non-ESFF baghouses. Published
correlations relating equipment size and cost are used in a model for predicting the
capital and operating costs of conventional pulse-jet baghouses. A comparison bet-
ween predicted capital costs and independently obtained estimates shows that the bag-
house model is capable of + or - 20% accuracy. A prototype design for ESFF hard-
ware is developed, and cost quotes from vendors are incorporated into a predictive
equation for ESFF costs. Because there are no pulse-jet ESFF baghouses, the pro-
totype design is subject to revision, a lack of certainty that restricts the accuracy of
ESFF cost predictions to + or - 30% accuracy.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
COSATI Field/Group
Pollution
Filtration
Fabrics
Electrostatics
Mathematical Models
Cost Estimates
Performance
Computer Pro-
grams
Pollution Control
Stationary Sources
Fabric Filters
Baghouses
13B
07D
HE
20C
12 A
14A
14G
09B
3. DISTRIBUTION STATEMENT
Release to Public
19. SECURITY CLASS (This Report/
Unclassified
21. NO. OF PAGES
108
20. SECURITY CLASS (This page)
Unclassified
22. PRICE
EPA form 2220-1 (9-73)
C-6
-------
|