EPA-450/ 3- 78-046 August 1977 FABRIC FILTER COSTS FOR LARGE COAL-FIRED STEAM GENERATORS U.S. ENVIRONMENTAL PROTECTION AGENCY Office of Air and Waste Management Office of Air Quality Planning and Standards Research Triangle Park, North Carolina 27711 ------- FABRIC FILTER COSTS FOR LARGE COAL-FIRED STEAM GENERATORS Prepared By Industrial Gas Cleaning Institute Stamford, Connecticut 06904 Contract No. 68-02-2532 Task No. 5 Prepared For U.S. Environmental Protection Agency Strategies and Air Standards Division Economic Analysis Branch Research Triangle Park North Carolina 27711 August 1977 ------- CONTENTS Page 1.0 INTRODUCTION 1-1 2.0 PROCESS DESCRIPTION 2-1 3.0 PARTICULATE EMISSION CONTROL BY FABRIC FILTER 3-1 3.1 Specifications 3-1 3.2 Investment 3-1 3.3 Annualized Costs 3-1 APPENDIX FABRIC FILTER SPECIFICATIONS A-2 ------- LIST OF FIGURES No. Page 2-1 Typical Fabric Filter Arrangement 2-3 3-1 Capital Cost of Fabric Filters 3-3 Used on Large-Sized Boilers 3-2 Annualized Costs of Fabric Filters 3-5 Used on Large-Sized Boilers 11 ------- LIST OF TABLES No. Page 3-1 Capital Cost Data for Fabric Filters 3-2 Used on Large-Sized Boilers 3-2 Annual Operating Cost Data for Fabric 3-4 Filters Used on Large-Sized Boilers 111 ------- 1. 0 INTRODUCTION The purpose of this task is to determine the costs of fabric filters to control particulate emissions from large coal-fired steam generators. These costs are to be a func- tion of boiler size only. The emission limit (0.01 gr/acf) and coal specification are assumed to be identical for each application. The scope of this report is limited to the development of capital and annualized costs of fabric filters on boilers firing pulverized coal. Investment costs cover the fabric filters, inlet and outlet duct transitions, foun- dations and support steel, equipment erection, painting, and electrical work. A turnkey cost will be determined by add- ing these direct costs to the indirect installation costs, which include engineering, construction, field expenses and fees, startup, and contingencies. The above costs include the piping and valve components of a fly ash collection and handling system from the fabric filter hoppers to a common collection point. Annualized costs are defined as the direct costs of fabric filter operation plus fixed costs for overhead and 1-1 ------- capitalization. The cost of fly ash disposal is excluded, because some utilities have adequate space for on-site disposal. The specifications (see Appendix) cover fabric filters that treat flue gas under conditions involving the following combination of variables. Boiler size, MW 200 500 700 Emission regulation, gr/acf 0.01 0.01 0.01 lb/10b Btu 0.033 0.033 0.033 The specifications were sent to three IGCI members recom- mended by the Engineering Standards Committee as experts in this field of application. The quotations received were tabulated and averaged. Estimated installed costs of valving and piping for an ash handling system were added to this average figure. The efficiency data provided in this study represents the maximum performance that can be guaranteed by the equip- ment suppliers. These values will be obtained when the collection equipment is in good condition and operating within design flow specifications. This does not mean that these efficiencies will be achieved all of the time. Un- foreseen upsets in process gas flows or conditions such as a change in process chemistry or an excessive dust loading will 1-2 ------- affect performance. Good maintenance procedures are necessary to maintain high-level efficiency. 1-3 ------- 2.0 PROCESS DESCRIPTION Figure 2-1 depicts a coal-fired utility boiler equipped with a fabric filter for particulate emission control. Air is blown into the boiler by forced-draft fans, and induced draft fans are used to pull the cleaned flue gas through the fabric filter to make up for pressure drop through the filter and to operate the boiler in a balanced-draft condition. As an economy measure, air passes through a heat exchanger designed to recover heat from the hot exhaust gases. In the boiler, pulverized coal burned with the preheated air generates steam from boiler feed water. Coal combustion produces ash (a noncombustible coal residue) and hot gases. Although a small amount of the ash falls to the bottom of the combustion chamber and is sub- sequently removed as bottom ash, 70 to 95 percent of it is entrained (as fly ash) in the hot gas stream. Because this material is of such fine particle size, it is difficult to separate from the combustion gas stream. A fabric filter may be used to remove this fly ash from the boiler exhaust gases. Fabric filters are selected for particular boiler installations on an economic basis, which depends on the 2-1 ------- type of fabric used, method of cleaning, and the air-to- cloth ratio. The chemical composition of the fly ash affects filter performance somewhat, mostly through corrosive problems, Acid condensation can cause corrosion within the filter; however, this occurs only when the gas stream is lowered below 300°F. As boiler exhaust gases pass through the fabric filter, fly ash particules contained in the gas are collected pri- marily by direct interception and inertial impaction. Periodic cleaning of the fabric (by mechanical shake and/or reverse air) causes the accumulated particles to fall into collecting hoppers beneath the filter compartments. The cleaned exhaust gases are sent through an induced-draft fan to a stack and are ultimately discharged to the atmosphere. When the fly ash collected in the hoppers reaches a specified level, valves discharge it to a pneumatic conveying system for transport to a disposal area. Sometimes the hop- per disposal process is timer-actuated rather than controlled by a level indicator. 2-2 ------- I U) FLY ASH COLLECTION HOPPER Figure 2-1. Typical fabric filter arrangement. ------- 3.0 PARTICULATE EMISSION CONTROL BY FABRIC FILTER 3.1 DESIGN SPECIFICATION The design specifications for fabric filter operation on three boiler sizes are presented in the Appendix. The fabric filter efficiency and residual particulate emission values shown are directly correlated with the emission con- trol level considered-0.01 gr/acf, or 0.033 Ib/MM Btu. 3.2 CAPITAL INVESTMENT COSTS Table 3-1 presents the capital investment required for fabric filters to achieve the particulate emission control level when operating under design conditions. The various cost items shown represent the sum of the fabric filter costs and installed costs of piping and valves for a fly ash handling system. Fabric filter auxiliary equipment typically includes access and supports. Ash handling auxiliary components (storage silos, unloaders, controls, etc.) are not included. Duct and stack costs are not included in the direct costs of installation because only flange-to-flange costs of the fabric filters are considered. 3.3 ANNUALIZED OPERATING COSTS Table 3-2 shows the estimated total costs of operating 3-1 ------- CAPITAL COST DATA FABRIC FILTER FOR LARGE SIZED BOILERS Do Sheet No. I of 2 Project No. 68-02-2532 Task No. 5 BOILER SIZE Megajoules/sec or MW Inlet & outlet gas flow ACFM OF SCFM Moisture, Vol. % Contaminant loading Inlet, gr/ACF Inlet, Ib/hr Outlet, gr/ACF Outlet, Ib/hr Cleaning efficiency Gas cleaning equipment cost Cost of auxiliaries Installed ash handling equipment Total equipment cost Installation costs, direct* Foundation and supports Duct work Stack Piping Insulation Painting Electrical Total direct costs Installation costs, indirect Engineering Constr. and field expense Construction fees Start-up Performance test Contingencies Total Indirect costs Turnkey cost 200 798,000 350 520,000 10 1.46 9,970 0.01 70 99.3 1,884,800 376,000 2,260,800 732,200 99,700 By By 17,400 528,000 41,000 159,800 1,578,100 459,700 180,600 396,300 265,900 17,800 12,300 70,900 1,403,500 5,242,000 500 1,993,000 350 1,305,000 10 1.46 24,930 0.01 175 99.3 4,077,000 1,038,000 5,115,000 1,309,500 221,200 Others Others 41,800 1,196,000 91,100 378,000 3,237,600 914,900 303,900 788,900 592,700 32,700 15,800 157,300 2,806,200 11,158,800 700 2,790,000 350 1,826,000 10 1.46 34,900 0.01 245 99.3 5,605,100 1,267,000 6,872,100 1,838,100 292,900 58,100 1,630,000 121,200 628,700 4,569,000 1,269,200 382,700 1,099,200 817,000 41,00-0 17,200 212,100 3,838,400 15,279,500 * Where specified Table 3-1. CAPITAL COST DATA FOR FABRIC FILTERS USED ON LARGE-SIZED BOILERS 3-2 ------- 10" I I I I 5 4 3 2 oc. •f. t— oo o 10' 5 4 OEQUIPMENT COST A TURNKEY COST 10C J I 2345 10° GAS FLOW (SCFM) 345 10' Figure 3-1. Capital cost of fabric filters used on large-sized boilers. 3-3 ------- ANNUAL OPERATING COST DATA FABRIC FILTERS Data Sheet No. 2 of 2 Project No. 68-02-2532 Task No. 5 Mega joules/sec. BOILER SIZE or MW Inlet & outlet gas flow ACFM OF SCFM Moisture, Vol. % Contaminant loading Inlet, gr/ACF Inlet, Ib/hr Outlet, gr/ACf Outlet, Ib/hr Cleaning efficiency Operating cost item Unit cost Direct costs: Operating labor Operator $10/manhour Supervisor $12/manhour Total Maintenance Labor $10/manhour Materials Total Replacement parts Utilities Electricity $0.03/kWh Pressure drop across collector Flange to flange AP, maximum , minimum Total Total direct costs Capital charges Total annual cost 200 798,000 350 522,000 10 1.46 9,970 0.01 70.0 99.3 20,900 6,000 26,900 14,500 1,900 16,400 57,200 243,000 6-8, "W.G. 5-5 1/2 343,500 891,100 1,234,600 500 1,993,000 350 1,305,000 10 1.46 24,930 0.01 175.0 99.3 23,200 6,400 29,600 27,900 3,500 31,400 119,500 571,900 6-8 5-5 1/2 752,400 1,897,000 2,649,400 700 2,790,000 350 1,824,000 10 1.46 34,900 0.01 245.0 99.3 25,900 7,000 32,900 37,100 4,200 41,300 160,800 786,000 6-8 5-5 1/2 1,021,000 2,597,500 3,618,500 Operating costs to be based on annual operation of 8760 hours per year @ 65% capacity factor. Table 3-2. ANNUAL OPERATING COST DATA FOR FABRIC FILTERS USED ON LARGE-SIZED BOILERS 3-4 ------- 10' I I 5 4 3 P 2 oo § 1/1 I— 00 I- 8 5 4 3 O DIRECT COSTS A TOTAL COSTS J I I I I 45 10° GAS FLOW (SCFM) 10' Figure 3-2. Annualized costs of fabric filters used on large-sized boilers. 3-5 ------- a fabric filter under the specified conditions on 200-, 500- and 700-MW units, respectively. These costs are predicated upon operation of the fabric filters at 65 percent capacity (load) factor. The total costs represent the average of the direct operating costs submitted by the three IGCI members and the computed overhead and capitalization charges. Fan operation (both induced-draft and reverse-air) for air movement is included. Utility costs of ash conveying are not included. 3-6 ------- APPENDIX FABRIC FILTER SPECIFICATIONS A-l ------- APPENDIX A 1.0 FABRIC FILTER SPECIFICATIONS A fabric filter is to remove solid particulate matter from the exhaust flue gas of a large pulverized coal-fired boiler. The system shall be quoted complete, including the following: 1. Fabric filter 2. Structural steel for installation of the fabric filter with at least 5 feet clearance under ash discharge 3. Insulation, 2" thick 4. Reverse air cleaning, including reverse air fan 5. Slide gates 6. Dust collection hoppers 7. Other necessary auxiliary equipment including cleaning cycle sequence timers. Ash handling equipment and controls are not included in these specifications. Details: 1. The fabric filter shall be of compartmental construction to allow isolation of a single compartment for cleaning and maintenance. 2. Pneumatic or electric remote control gate valves shall be provided to isolate modules, and ductwork shall be provided to allow for a single inlet and a single outlet connection to and from the fabric filter. A-2 ------- Construction shall allow for suction operation of the fabric filters; the induced draft fan will be attached to the fabric filter outlet. The con- necting ductwork will be supplied by others. Housings, valves and ductwork shall be of carbon steel construction. Fabric shall be fiberglass. System Requirements The attached data sheets outline the system variations on which quotations will be received, and provides inlet and outlet flow rates and particulate loadings. The gas cleaning device is to reduce the solids content of the gas to the levels specified. The coal being fired in the boilers has the following analysis: 0 Sulfur 0.5% Ash 5.9% 0 Moisture 28.1% 0 Heat value 19.36 Joules/nanogram 8,322 (Btu/lb) Size distribution of particles in the inlet gas is as follows: Particle size Percent by weight* Above 100 microns 10 40 to 100 microns 15 20 to 40 microns 15 10 to 20 microns 20 Below 10 microns 40 * From Fine Particulate Emission Inventory and Control Survey, by the Midwest Research Institute, January 1974. A-3 ------- CAPITAL COr.T DATA FABRIC FLLTF.R FOR LARGE SIZED BOILERS Data Short No. _ Project No. 68-02-2532 Task no. 5 BOILER SIZE Mega joules/sec. or MW Inlet and outlet gas flow ACFM CF SCFM Moisture , Vol . % Contaminant loading Inlet, qr/ACF Inlet, ib/hr Outlet, gr/ACF Outlet, Ib/hr Cleanina efficiency Gas cleaning equipment cost Cost of auxiliaries Total equipment cost Installation costs, direct* Foundation and supports Duct v.1 o r k Stack Piping Insulation Pa inting Electrical Total direct costs Installation costs, indirect Engineering Constr. and field expense Construction fees Start-up Performance test Contingencies Tcta] Indirect costs Turnkey cost 200 798,000 350 520,000 10 1.46 9,970 0.01 70 99.3 500 1,993,000 350 1,305,000 10 1.46 24,930 0. 01 175 99. 3 .. 700 2,790,000 350 1,826,000 10 1.46 34,900 0.01 245 99.3 * U'here spec i f icd A-4 ------- ANNUAL OPERATING COST DATA FABRIC FILTERS Data Shed No. Project No. 68-02-2532 Task No. 5 Mega joules/ sec . BOILER SIZE or MW Inlet & outlet gas flow ACFM Op SCFM Moisture, Vol. % Contaminant loading Inlet, gr/ACF Inlet, Ib/hr Outlet, gr/ACF Outlet, Ib/hr Cleaning efficiency Operating cost item Unit cost Direct costs: Operating labor Operator $10/manhour Supervisor $12/manhour Total Maintenance Labor $10/manhour Materials Total Replacement parts Utilities Electricity $0.03/kWh Pressure drop across collectc Flange to flange AP, maximum , rnimimum Total Total direct costs Capital charges Total annual cost 200 798,000 350 522,000 10 1.46 9,970 0.01 70.0 99.3 3r 500 1,993,000 350 1,305,000 10 1.46 24,930 0.01 175.0 99. 3 700 2,790,000 350 1,824,000 10 1.46 34,900 0.01 245.0 99.3 Operating costs to be based on annual operation of 8760 hours per year @ 65% capacity factor. A-5 ------- TECHNICAL REPORT DATA (Please read Imumeiions on the reverse before completing! 1 REPORT NO. |2 EPA-450/3-78-046 | 4. 7. 9. 12 15 16 17 a. TITLE A\DSUBTITLE Fabric Filter Costs for Large Coal-Fired Steam Generators AUTHOR(S) John Bruck, N.D. Noe PERFORMING ORGANIZATION NAME AND ADDRESS Industrial Gas Cleaning Institute 700 N. Fairfax Street, Suite 304 Alexandria, Virginia 22314 . SPONSORING AGENCY NAME AND ADDRESS U.S. Environmental Protection Agency Office of Air Quality Planning and Standar Research Triangle Park, North Carolina 277 . SUPPLEMENTARY NOTES 3. RECIPIENT'S ACCESSIOONO. 5. REPORT DATE August 1977 6. PERFORMING ORGANIZATION CODE 8. PERFORMING ORGANIZATION REPORT NO. 10. PROGRAM ELEMENT NO. 11. CONTRACT/GRANT NO. 68-02-2532, Task 5 13. TYPE OF REPORT AND PERIOD COVERED Final Je 14. SPONSORING AGENCY CODE 11 . ABSTRACT Capital and annual ized costs are provided by vendors for fabric filters used for particulate emission control of large coal-fired steam generators. Generator sizes of 200, 500, and 700 megawatts are considered at an emission level of 14.3 nanograms per joule (0.033 Ibs/million Btu) both equipment and turnkey costs are provided. KEY WORDS AND DOCUMENT ANALYSIS DESCRIPTORS Air Pollution Cost Estimates Dust Control 19 ClSTPIBUTION STATEMENT Unl imited b. IDENTIFIERS/OPEN ENDEDTERMS Air Pollution Control Stationary Sources Coal-Fired Boilers Fabric Filters Emission Standards 19. SECURITY CLASS (This Report) Unclassified 20. SECURITY CLASS /This page/ Unclassified c. COSATI Field/Group 13B 21. NO. OF PAGES 21 22. PRICE EPA Form 2220-1 (9-73) ------- |