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