ESL-IE-84-04-1441

CIRCULATING FLUIDIZED BED COMBUSTION BOILER PROJECT

Stanley B. Farbstein, BFGoodrich Chemical Group, Cleveland, Ohio Terri Moreland, Illinois Department of Energy and Natural Resources,

Springfield, Illinois

ABSTRACT

The project to build a PYROFLOW circulating fluidized bed combustion (FBC) boiler at the BFGoodrich Chemical Plant at Henry, Illinois, is described. This project is being partially funded by Il11noi5 to demonstrate the feasibility of utilizing high-sulfur Illinois coal, Design production is 125,000 pounds per hour of 400 psig saturated steam. An Illinois EPA construction permit has been received, engineering design is under way, major equipment is on order, ground breaking occurred in January 1984 and planned commissioning date is late 1985. This paper describes the planned installation and the factors and analyses used to evaluate the technology and justify the project. Design of the project is summarized, including the boiler performance requirements, the PYROFLOW boiler, the coal, limestone and residue handling systems and the pollutant emission limitations.

INTRODUCTION

The BFGoodrich Chemical Group has eleven U.S. plants located from New Jersey to California and from Ohio to Texas. These plants have 47 boilers which in 1983 were used to produce 12 billion pounds of steam consumed chiefly for process heat, but also for some comfort heating,

In 1978, because of the rapid price run up of oil and gas used for boiler fuel that began in 1972 and which was projected to continue and because of the occasional curtailments or allocations of boiler fuel, Goodrich undertook a program with the goal to replace the oil and gas used as fuel for base load steam generation with alternate sources of energy by 1990. A priority list was established for the various plant locations. By 1981, six coal-fired boilers were in operation and in 1983, 27 percent of all steam generated was from coal, as compared to only 11 percent in 1980. Steam from gas and oil dropped from 44 percent in 1980 to only 26 percent in 1983 (Table 1).

T.'\[Jl.F. 1 S'I'EAN PRO("JI1(,~I(;N l\tW USE

StPiHn [1f;C, -BTiTion Pounds 10.9 12.0

Coal II. 3 27.3 h"ilsle Heat 24.3 21.8 Dy-Product Fuel 18.3 22.7 Natural Gas/Fuel 00 43.5 25.7 Purchased Steam 2.6 2.5

Coal-F'irf:'d Boilers 1n Op('rat1on

One premise of the program was that any new coal-fired boilers to be installed should include provisions to control S02 in the emissions. This decision was made not only to assure compliance with present and projected emissions requirements, but also to provide the long-term opportunity to take advantage of the lowest cost fuels.

The first two new boilers installed were at Louisville, Kentucky and Convent, Louisiana and were of conventional spreader stoker designs. The Convent boiler was the first coal boiler in an industrial plant in Louisiana,

NEW COAL BURNING TECHNOLOGY

Included as part of our program was the commitment to evaluate new and emerging coal burning technology. One of the potentially attractive new technologies was fluidized bed combustion (FBC). Our interest in this technology was stimulated because of our use of fluidized bed catalytic reactors in several processes for chemical manufacture.

In a chemical plant, loads change rapidly as processes are started up and shut down and as reactions reach stages which reqUire changed energy input. Further, total steam demand swings widely with season and production levels. Accordingly, our requirements for a boiler include a high turndown ratio and rapid response to load changes with efficient

821

ESL-IE-84-04-144

Proceedings from the Sixth Annual Industrial Energy Technology Conference Volume II, Houston, TX, April 15-18, 1984

performance at rates from one-third to full load, and at 10 d changes of 20 percent of full load in ten minutes.

Our examination of the early experience with the f:Lxed bed or first generation FBC boilers indicated lack of this capability for load change or turndown so we delayed consideration of installation of a FBC boil r.

CIRCULATING FBC

In early 1980 we became aware of the work by the Ahlstrom Company of Helsinki, Finland in the development of the circulating FBC boiler design. The PYROFLOW technology which Ahlstrom had been developing since 1976 and was then testing in a product ton unit seemed to meet our operating requirements for turndown and load re sponse.

The principle of the circulating fluidized bed system c n be expl tned by examining the relationship between differential pressure and superftclal gas velocity for a bed of particles (Figure 1). For a fixed bed, the log of differential pressure Is approximately proportional to the log of gas velocity. As the gas velocity increases beyond the minimum fluidization vela ity, th bed of particles begins to expand and become fluidized. and a distinct bed level ls visible. The differential pressure remains almo. t constant until the bed material begins to elutriate or be carried out of the bed at the entrainment velocity. The degree of turbuient mixing continues to lucreas between the minimum and the entrainment velocity.

FIX(D IU !IUBBLlNG TURBULENT >ED BED

CIPCULATlHG.ED

-- lOG IVElDtfTYl

fNUA ,.fllT 'iELCClTY,

FIGlllll! L PRESSURE DROP VS. GAS Vl!LOCITY IN FLUIDIZED BEDS

B yond the entrainment velocity. some particles are carried out of the bed, and a continuous process is malntai ed by recirculating the partIcles to the bottom of th bed. The en ralnment velocity marks the transItion from a fixed bed to a ircula lng bed. Beyond this v ocity, the differential pressure becomes a functlon of velocity and solids recirculation ra e. This princi Ie has been applied to FBC coal-fired boilers.

A fixed fluidized bed oper tes wlth air velocIties that can only vary between the minimum and the entrainment velocities. higher velocities, the bed material becom entrained, and there Is carry-over of unb particles from th combustion chamber. A velociti s close to the minimum fluidizat velocity. thp bed or portions of the bed slump, causing 10 alized hot spots.

In contrast to the fixed ed, the circulat n fluidized bed system can use greater aIr velocitlps because the entrained particles separated from the hot gases and reinjecte into the bottom of the combustion chamber. Turndown ratios of up to 3:1 can be achiev ch nging the air flow rates and fuel feed. Load changes greater than 20 p~rcent withl minutes have been demonstrated.

Figure 2 is a conceptual drawlng of the PYROFLOW circulating FBC boiler system. 1- was developed by the Ahlstro Company and 1s offered 10 the U.S. by the Pyropower Corporation of Sa Diego. Fuel and limest ne are fed into the lower part of the combust: on chamber, and primary air. ls introduced thr ugh a supporting grid. Because of the turbulelce In th circulatlng bed, the fuel mixes qul kly and uniformly with the ed material. Ther is no fixed bed d pth. The de sity of th be varies, with the highest denslty at the Ie el where the fuel is introduced. Secondary a r is introduced at varIous levels (1) to ensure gas velocities In the upper part of the combus or high enough for particle entrainment, (2) 'a provide staged combustIon conditions to re uce produc tion of Ox. (3) to supply air to bu n fines in the upper part of the combustion chamber, and (4) to assIst in t~mperature control of the combustion chamber..

nGt:R~ 2 PYROFLOW CIRCULIITTNC

FI.UrDIZP.D tiED COHUUortoN DOILU

822

ESL-IE-84-04-144


A combustion temperature of 15500f is optimum for S02 capture. This temperature is reasonably constant throughout the proces because of high turbulence and circulation of solids. This low combustion temp ture, along with staged secondary air injection, results in minimal NOx formation.

Velocity of the hot gases is reduced as they leave the combustion chamber. This reduction, along with an increase in cross section, causes large entrained particles of coal and limestone to drop out of the gas stream into a hot cyclone collector. This solid material is collected and reinjected into the combustion chamber through a nonmechanical seal to achieve high raw material efficiency. Solids too small to drop out in the hot cyclone collector are carried to the baghouse for final p rticulate removal from the cooled gas stream before it is discharged to the atmosphere. Residue is removed from the bottom of the combustion chamber as bottom ash and from the baghouse as fly ash.

A portion of the heat is absorbed in the combustion chamber, and the remaining heat is recovered in the convection section of the boiler. There are no tubes in the lower, most dense portion of the bed.

The combustion chamber is of water wall construction that provides a gastlght enclosure. The lower portion, which is the dense bed region, is partially covered with refractory.

The cyclone collector, which is located at the outlet of the combustion chamber, is a steel vessel lined with two laye s of castable refractory. The outer layer is designed for the high-temperature and abrasive characteristics of the entrained solids; the inner layer is a lightweight insulating refractory.

In 1979, Ahlstrom started up a 45,000 pound per hour PYROFLOW unIt at Pihlava, Finland. In 1981, 200,000 pound per hour boiler was started up 1 Kauttua, Finland as le b se load steam supply for paper mill. Currently, there are fourteen PYROFLOW units 1n opp~ation including one in Bakersfield, Californl in oil field service and about si~ in design or constructio phases.

After a series of visits by Goodrich engineering personnel and executives, including witnessing of performance tests of the PYROFLOW boiler in Kauttua, Finland, we concluded that this technology offered sufficient advantages to justify the technical risk of the installation of the first circulating FBC boiler in a U.S. industrial plant.

THE HENRY PLAN

One of the eleven domestic Goodrlch chemical plants is located at Henry, Illinois. Thls location 1s bout 120 miles southwest of Chicago and 30 miles north of Peoria on the west bank of the Illinoi River. The area is predominately rural and the Goodrich plant is th largest industrial facility in the immedla te ar.ea.

Goodrich established its Henry plant in 1958. There are presently two major product lines; polyvi y1 chloride plastics and r sins and polymer chemicals. There are approximately 350 employees.

Steam at the Henr.y plant 1s urr ntly produced in two Combustion Engineering boilers, each with a capacity of 100,000 pounds per hour of s turat d steam at 220 psig and 400Op. The boilers can be fired with either gas or No. 2 oil, but gas has bee the major fuel, and .tn r cent years oil has been used only when gas was curtailed.

The average annual ste m load at the Henry plant is 80,000 pounds per hour. Winter average load is bout 100,000 pounds per hour and during the summer, the average load drops to 70,000 pounds per hour. Instantaneous peak load in severe winter weather is 145,000 pounds per hour. In th summer, the steam is used for process heat, and In the winter season there is an additional demand for ste~m for comfort heating.

The chemic 1 industry is very energy intensive, and Chemical and Allied Products are the largest energy consuming sector of the manufacturing industries, consuming 23 percent of all energy used by U.S. manufactu~ers in 1981.

Products made t the Henry pI nt are typical of the ch mical industry in that they are all energy intensiv. En rgy osts at Henry make up the largest singl share of the cost to convert the raw materials to finished products.

The plant has an aggressive energy conservatlon program which has succeed d In reducing the nergy required pp~ unit of production. In

1983, this figure was 3 percent less than In 1982, and in 1984 and 1985 further reductions of 4 percent nd 3 percent in energy consumption per. unit of production are projected, WHY PUT THE FBC BOILER AT MENRY?

Despite good progress in energy conservation, energy costs at the plant have incr ased rapidly, due primarily to the incr.ease In the cost of natural gas used as boiler fuel.

823

ESL-IE-84-04-144


Natural gas at Henry is supplied by Central Illinois Light Company (CILCO) which also supplies electricity. CILCO, in turn, obtains essentially all of its natural gas supply from the Panhandle Eastern Pipeline Company. Gas prices have increased from $0.48 to $5.45 per million Btu in the last 12 years (Figure 3), and, despite our energy conservation program, the total cost of boiler fuel at Henry has increased 800 percent in the same period. Further, it is projected that such cost increases will continue at rates substantially more rapid than the rate of inflation.

FICURE J NATUKAL CAS PRICES AT HENRY

In order for the Henry plant to remain competitive with the plants of its domestic and foreign competitors, boiler fuel costs had to be reduced. Accordingly, the Henry plant was assigned a high priority in Goodrich Chemical Group's plans to reduce the use of oil and gas as boiler fuel.

The Henry plant has many potential advantages for the first industrial installation of a circulating FBC boiler using high sulfur coal.

Illinois has the largest reserves of coal of any state. Unfortunately for the coal industry and coal miners, most of this is high-sulfur coal, and the coal industry in Illinois has excess capacity. There are a number of working coal mines within economical truck delivery of Henry, and its location on the Illinois River makes the plant accessible to barge delivery of

coal from the numerous coal mines in souther Illinois (Figure 4). Thus, there is the potential for a long-term supply of coal at a competitive price.

~'..

___pO.'''-

FleURE 4

lLtlNOIS COU:\T1E.S WlTH ACT1\'t: COAL HIN S J980

Illinois has abundant supplies of limestone and there are a number of active quarries within economical trucking distance of the plant (Figure 5). Further, the Argonne Laboratory program to evaluate limestones f r use in FBC has found a number of Illinois sources to be potentially applicable.

Fl CUR[ 5 ILLINOIS Cf'UN'rtF.S \"ITH ACTlV[ t1.:-!ESTONC Qil" R~!:$

19~O

824

ESL-IE-84-04-144


In Lts 25 ypar.s of oppration, the Henry plant has had a history of speedy and effective adoption of new processes and technology. The plant has high productivity and quality and has achieved an outstanding safety record. The plant work force was enthusiastic about the new coal boiler. Accordingly, Goodrich management concluded that the new boiler should be installed at the Henry plant. When the new boiler is in operation, the steam produced by it will replace steam generated in the two existing gas/oil boilers which will be placed in standby and used only as backup.

The State of Illinois, through its Coal Bond Fund, is providing to Goodrich a grant of $4.3 million as a share of the construction cost of a circulating FBC boiler to be built at Henry. This grant was made to demonstrate the innovative new process to use high-sulfur Illinois coal in an environmentally acceptable fashion.

For these various reasons, Goodrich management in July 1983 approved construction of a PYROFLOW boiler to be built at the Henry plant, and ground was broken on January 13, 1984.

DESCRIPTION OF BOILER AND SUPPORT SYSTEMS

Project Summary The PYROFLOW boiler to be installed at Henry is being designed to produce 125,000 pounds per hour of 400 psig saturated steam.

Based on projected steam demands, the boiler will operate at an average hourly rate of 96,300 pounds per hour. Operating at this rate and allowing for. downtime, it will consume almost 50,000 tons per year of high-sulfur Illinois coal. Limestone use is projected at 11-14.000 tons per year. Solid residue (ash, spent limestone and calcium sulfate) to be disposed will be 15-22,000 tons per year.

This projected use of limestone is based on the use of Illinois No. 6 coal with a sulfur content of 3.5 percent. Since sulfur content varies widely in Illinois No.6 coal, the bol1pr is being designed with the capability to use coal with up to 5.5 percent sulfur.

The boiler is designed for an overall energy efficiency of 83 percent with a carbon utilization of 98.5 percent and a limestone utilization of 2.5/l:calciumlsulfur on a molar basis.

A system flow diagram showing the various systems of the Henry FBC boiler project is shown in Figure 6.

nr.unr. 6 SCH~TIC nOWSIIF.F.'!' OF HENRY Fnc 8CTLER

ProjPct Schedule Detailed design and engineering on the project is currently underway in the Goodrich Central Engineering Department in Cleveland, and in Pyropower's offices in San Diego. As of April 1, it is estimated that engineering was 30 percent complete. Ground breaking occurred on January 13, 1984. but because of the severe weather, field work was limited until AprLl.

Pyropower was authorized to begin engineering work in October 1983 and a contract for construction and installation of the PYROFLOW boiler by Pyropower was signed on December 6, 1983.

Some of the important project milestones which have been passed are shown in Table 2 and the present schedule for major future events is shown in Table 3.

TAOI.F. 2 foil LESTOlH-:S Pl,SSEO

Illinc.is Goede ich

PON Proposal

Sept Dec

'81 '81

IlUnaj'j Grdnt Junc' 182 Env i ronfl'cntal Pcrmi ts Coodrich Projt'!ct: Rp!cilse Oc:,ign tngincering Eiegun Agree-me-Ilt with Jllinoi~

Sept July Oct Dec

& Oct 182 '83 '8] '8J

Contriict wi ttl Pyropowec Ground Break 10g

Dec Jan

'8] '84

Procuc('rtl(!nt B@gun Mnr '84 Field Wuck Stepped up Apt '84

T/,8LI::: J HrLF.STO:H..;..:o SCHr.OllLED

Founda Lions "lay 'S"-Mac '85 oosi9n I::ngineering Co ....plptet

Pyropow,,"c July '84 Goode ich Aug 'a"

Stack and Baqhouse Set and erect July-NoY '84. Boiler House I::-rect ion Sept '84-Mar 'S5 Boiler Erection Dec '94-June '9~ Mechanical Equipment Set Dec 'S4-May '85 Electe ical Jan-Aug 'SS riping Fcb-July 'as AcCCi\clory ,"Jar-Ape "85 Inst[um

Coal Syst~m

Coal will be received by truck and will normally be unloaded into a yard hopper. A paved coal storage area is being provided with capacity for a 3D-day supply of 5,000 tons, and coal for storage will be unloaded directly to the storage area. When coal is recovered from storage, it will be dumped into the yard hopper wlth a front end Loader which also will be used for bUilding the coal storage pile. Coal from the yard hopper will be conveyed by a covered belt conveyor through a magnetic tramp iron separator and into a crusher.

The coal will be crushed with a hammer mill to 1/2 inch and below. Provisions are included to bypass the crusher if presized coal is purchased. The crushed or sized coal will be transferred by a dense phase pneumatic conveying system to the steel storage silo. The level of the storage silo will control the conveying operation.

The silo can hold 450 tons of prepared coal and will be filled during an eight-hour day, five days per week. The silo is sized to permit four days of coal storage.

Coal will be fed out of the silo by a weigh belt f~eder which is controlled automatically by the combustion controls to satisfy steam demand.

The coal transfer points and storage silo include dust collectors for particulate emission control.

Limestone System

Crushed and sized limestone will be delivered to the site by truck and conveyed by a pneumatic transport system into a 350-ton limestone storage silo. The silo will be filled in an 8 hour day, 5 days per week operation and is sized to permit four days of limestone storage. The silo has level probes to determine level. The limestone storage silo includes a dust collector for particulate emission control. Limestone will be fed out of the silo by a double helix screw conveyor with the rate controlled by the level of S02 in the stack gas.

PYROFLOW Boiler

The primary PYROFLOW boiler components are the combustion chamber and the hot cyclone collector (Figure 7). Combustion and sulfur capture take place in the combustion chamber. Walls of the combustion chamber are water-cooled and provide about 45 percent of the heat transfer with the remainder in the convection zone. Primary air is introduced into the lower portion of the chamber, where the dense bed material is fluidized and larger

particles are retained. The upper portion contains the entrained bed region of less de se material. Secondary air is introduced at various levels as necessary to ensure complet combustion.

.~, ..~STEAMORUM'.:.: ) ...." . "

I I I J.~~. l ~~ . : ._1~, .. ,., ....1 i' (. 4.., r'

."'. \. ".~ ': .'~g~L~~~~oRNE~r- .~ II .' 1( ii~' ' . I

r..... l'V- ./; , COMWSTION ~. -', ,; po, , ';'. 1,51T I CHAMBER -~ 1 /;,;;I.~ I~-

,'. ,J. 'mi'5':"l~' !--~ECONOM1SER . '-: \ . .~, BOILERI 'ff' . ~r; ~.: ;.:.~_ :",1511 EXIT GAS

SECONOARY ' OOWNCOMER..r....;AIR fAN ~.~ ....-:;.c ~\'I'"t,r- ;;:----"'ASH REMOVALPRIMARY Urii " ':.. 1.'.'~ AIRfAN-' :~

FIGURE 7 PYROFLOW FLUIDIZED BED

COMBUSTION BOILER LAYOUT

Coal and limestone for sulfur retention and control are introduced into the fluidized bed in the combustion chamber. Air velocities of B to 25 feet per second are used to circulate th bed through the combustion chamber and into a hot cyclone collector that separates the hot gases from solids (unburned coal, unreacted calcium oxide, calcium sulfate and ash).

Combustion products pass from the combustion chamber to the hot cyclone collector where entrained particles are separated from the flue gas. The collected particles fall by gravity to a lower chamber, where they pass through a nonmechanical seal and return to the combustion chamber.

Flue gas exits the hot cyclone collector and continues to the convection zone, transferring heat to the boiler bank and economizer. From the convection zone, the flue gas continues to the dust collection system, where entrained particles are removed to satisfy environmental requirements. The flue gas is then discharged to the stack via an induced-draft fan.

Combustion air is supplied by primary and secondary fans which take their suction through two inlet ducts from the inside of the boiler house. The primary air is added below an air

826

ESL-IE-84-04-144


distribution grid at the bottom of the combustion chamber. Secondary air is supplied to vartous locations at a low level tn the combustion chamber. Secondary air is also due ted to the start-up burners and two ash coolers. High pressure air for fluidizing recirculated and new feed materials is supplied by a rotary positive displacement blower to the nonmechanical seal below the cyclone collector.

Deaerated feedwater is pumped through the economizer and on to the steam drum. From the steam drum, water is delivered via downcomers to the walls of the combustion chamber and to the convection boiler bank. It is heated in these two sections and returns as a steam/water mixture to the steam drum. The convection boiler bank section provides 55 percent of the evaporative duty, and the combustion chamber provides the remainder. All evaporative sections are arranged for natural circulation. The steam is separated in the steam drum and supplied to the high pressure steam mains at 400 psig, saturated.

Combustion chamber bottom ash, including coal ash, calcium sulfate and calcium oxide, is removed from the lower part of the chamber through two ash coolers which recover sensible heat from the ash before it enters the ash removal equipment.

The boiler surfaces in the convection zone are cleaned by conventional steam soot blowing. Dust loading to the convection zone is lower than that in conventional boiler systems, because of ash removal in the hot cyclone collector. The 15500F combustion temperature is below the ash fusion temperature so that ash softening does not occur. This results in reduced soot-bloWing requirements.

Flue Gas Cleanup

Particulates are removed from the flue gas in a high efficiency pulse type baghouse which reduces the dust loading in the gas by 99.9 percent. The baghouse filter bags initially capture and retain the particulate matter by means of interception, impingement, diffusion, graVitational settling, and electrostatic attraction. Once a mat or cake of dust is accumulated, further collection is accomplished by sieving. The filter bags then serve mainly as a supporting structure for the dust mat responsible for the high collection efficiency.

The baghouse operation is controlled by a programmable controller which automatically sequences the pulse cleaning of the different compartments in the system. Periodically, the accumulated fly ash in the baghouse is removed for pneumatic transfer to the ash storage silo.

The filtered flue gas leaving the baghouse is moved by an induced draft fan to the top of a stack 195 feet high. Opacity and gas anatyzing monitors are provided to check the exit gas quality.

Residue System

A pneumatic dense phase ash conveying system automatically removes the by-products of combustion. The residue, which is a combination of calcium oxide, calcium sulfate, coal ash and miscellaneous inerts, is collected as bottom ash from the combustion chamber and as fly ash from the economizer, boiler bank and the baghouse. Ash from the various collection points is pneumatically conveyed to the two ash storage silos which are sized to hold four days of ash production. Bottom ash and fly ash are stored in separate silos and are transferred off-site for disposal.

Auxiliary Support Systems

The existing plant water treatment system will provide feedwater for the new boiler with modifications as required to meet the operating criteria of the FBC boiler in terms of water quality, pump capacity, and control reliability.

The electrical power needs of the boiler system require new switchgear for 4160V and 480V with a 2000 KVA, 480V transformer. To meet the requirement that the unit operate at design load regardless of electric power interruption, all major fan and pumps will have both electric and turbine steam drives. To reduce electrical demand, the normal drives wtll be 400 psig steam turbines which will exhaust to the 220 psig plant steam distribution system. An emergency generator wiLL prOVide standby power for the coal and limestone feeder motors, instrumentation, controls, lighting, etc.

Design connected electrical requirements of the boiler system will be 1,650 kw. However, because of the normal use of 400 psig steam to operate the large fans and pumps, the normal continuous electrical use at design rates will be 460 kw.

High efficiency motors and inlet vane control dampers on fans will be used to reduce electrical requirements.

Facilities will be installed to provide the compressed air requirements for the soot blowers, pneumatic transport systems, coal and ash systems, dust collectors, etc.

Boiler Location

The new boiler will be housed in a new building adjacent to the existing boiler house. The control room will be sized to allow the

827

ESL-IE-84-04-144


ont~ols from the existing boilers to be consolidated with the control system for the new boil~r. The new bUllding will also contaIn space for lockers and sanitary facilities.

el~ctrlcal switch gear. emergency generator and computer equipment a d office space for the utilitl 5 personnel.

ENVIRONMENTAL CONSIDERATIONS AND PER}UTTING The Goodr ch plant is located in Marshall County. Illinois which Is an Att inment Area for all of the National Ambient Air Quality Standards (NAAQS). Permitting for the n w boiler was under the Federal Prevention of Significant Deterioration (PSD) regulations. The 1111 ois Environmental Protection Agency (IEPA) conducted the P5D review and issued the P5D permit under the authority delegated to it by the U.S. EPA. Region V.

The circulating FEC boiler process provides solutions to several environmental problems inherent to a conventional coal-fired boller burning high-sulfur coal. Sulfur in the coal is captured in the form of calcium sulfate. thus eliminating the problem of S02 removal from flue gas. The low combustion temperatures (around 1550 OF), th turbulent combustion zone and the staged addition of combustion aIr result in low levels of NOx ' The calcium sulfate, mixed with the ash from the coal and the unused limestone, is drawn off as a dry residu from the combustion hamber bottom and the baghouse, thus eliminating the problem of handling and disposing of a sludge which is chara teri. ic of many add-on 502 scrubbing systems.

An air quality analysis was performed which :lnclud d ambient air quality monitorIng data, dispersion modeling of the proposed FBC boiler emisslons and an assessme t of the impacts on th ambient air quality. This analysis showed that the project would not vlolate the NAAQS and would comply with allowable P5D increments.

In addi~ion to the features of the boiler itself which result in control of S02 and NO x emissions, our installation includes a baghouse dust collector to control particulates in the flue g s. Baghouse dust collectors will also be installed 00 the coal conveying and storage system, the limestone system and the residue collection system. The IEPA determined that these controls represent Best A ailable Control Technology for parti ulate matter, 52, NOx and CO.

Emissio s of 52, NO x and CO will be monitored continually using nondispersive, infrared a d spectroscopic gas analyzers. acity will be measured using a dual pass transmissometer.

Coal will be stored on an imperm able surf c and runoff will be collected and treated in plant wa tewa er treatment system.

The existing boiler feed water tre tment sy will supply the new boiler. Effluent will contlnue to be treated in the plant water treatment system.

Solid residue will be disposed of In approve off-site landfills.

GoodrIch filed an application for an IEPA construction/operating permIt on March 25. 1982. This was supplemented with additional information .including modeling studies on Ap 19. 1982. Th IEPA filed public notice of i intent to issue a PSD permit on June 16, 198

he

em

i l s

and the PSD permit was issued on 1982 Table 4).

TADL.E 4 P&R>U'M'IN MILESTONES

IIlInoia e-PA PSD Permit Inlt:1al AppJi.c4LJ.on

upple ental FLUng Pub] ic Notice USUE'O

Illinois pen Vot ~nce Fcr CO Mequc.st t'lled Publ ic He1tt ing RcquCCt. Grantl!d

u.s. CPA RLlVi:!9joll TO lilinoh SIP Su mi ttpd y UUfiOll EPA Appro'!l!d

September 16.

Mr25~182 Apr 19, '82 Juno Hi, 182 Sept 16. '82

3une: 2a, '82 Sl'pt 17, '92 Oct 27, '82

Jan 4, '83 Sept 6, '8J

A request for a site specific variance for CO emissions was filed by Goodrich with the IllInois Pollution Control Board (IPCB) on Ju e 28, 1982. A public hearing was held on "his request on September 17. 1982 and on October 27, 1982, the IPCB issued an order granting th request.

The IEPA on January 4. 1983 submitted to the U.S. EPA a revision to the IllInois tate Implementation Plan incorporating tho IPCB order which the U.S. EPA approved on September 6, 1983. This completed all environmental permitting requirements.

These are the permitted lev 1s of the emIssion including the site specific variation for CO.

Particul te m tter - Not to exceed 0.06 pou ds per million Btu. 502 - Not to exceed 1.2 pounds per million Btu n a 30-day rolling average. eduction of at le st 85 percent. Ox - Not to exceed 0.6 pounds per million Btu. CO - Not 0 exceed 400 ppm.

828

ESL-IE-84-04-144


PROJECT ECONO~UCS

A budget-type capital cost estImate for the Henry project was prepared by the Goodrich Engineering Department in 1981 (Table 5). This estimate utilized recent in-house experlence from the construction of two coal-fired boilers plus revamp work on two others. The estimate of the installed cost of the PYROFLOW boiler ltself was provided by Pyropower. The estimated cost, including commissioning, was $21.3 million. The cost estimate was reviewed by a large A&E contractor who concluded that the Goodrich cost buildup was reasonable.

'r",aLE ~ flttf:LHIINAH,y CAPITAI_ ESTnIAT

!.-.!.!!l~i..9_~ sit~ pctp"r~tion l1Mi Other Civil 1.0 Buildint):11 and Services 1.2 P's:'HOPLO'1"l Boiler SystclI\ InStalled 8.5 Stack and l:ireetch inl] InStalled 0.7 Coal, Lirr;f!slon~ and 1\6h Handling und 2.5

Hif;cet!al\cous F.quiplllent ElecLricill nnd In~Ilr'Ullef)t

'I'I\IlLC 6 ~F:/"\~;} l'rV 1TV ANALY~~

lndex of Imp,'1ct on Di~coulltC'(J

CaCih flow

'~Il~t1 c,)~c 100 G.J!'i Pr ice Change!,;

Slower 88 [0'

production PYROFLOW boiler operate using coal containing a significant amount of sulfur. The Kauttua 200,000 pound per hour unit had, up to that time, burned only low sulfur Polish coal along with wood waste and peat. Ahlstrom arranged to test British coal containing almost 2.5 percent sulfur in the Kauttua unit with Swedish limestone used to capture the sulfur. Emissions were measured using U.S. EPA standards. Sulfur removal was 90 percent at a calcium/sulfur ratio of 2.5. NOx in the emissions was 0.42 pounds per million Btu.

Scale-up factor from the pilot plant unit to the 45,000 pound per hour unit was 10 and to the 200,000 pound per hour unit was 40. In both cases the production units performed as predicted or better based on the pilot plant results.

In the interim, the Pyropower Corporation which markets the PYROFLOW boiler in the U.S., installed in San Diego, California a PYROFLOW pilot plant unit. The combustion chamber is 16 inches in diameter and 25 feet high. Samples of three Illinois No. 6 coals and two Illinois limestones along with Ohio No. 6 and Lowellville, Ohio limestone have been evaluated in this unit.

The purpose of these tests were to screen Illinois sources of coal and limestone. The Ohio coal and limestone were evaluated to correlate the results from the San Diego pilot plant with results previously achieved in Finland. The correlation was good.

The three samples of Illinois No. 6 coal contained sulfur varying from 3.25 to 3.75 percent. The heat content on a wet basis varied from 10,900 to 12,000 Btu per pound. Performance of all three in the pilot plant were roughly comparable.

Performance of the two Illinois limestones differed more widely, but there is reason to suspect that the differences may be due more to the grinding and sizing of the two by the suppliers than differences in the fundamental character of original limestones.

The test results demonstrated the ability to achieve the Illinois EPA emissions requirements. S02 emissions of less than 1.2 pounds per million Btu were achieved with Illinois coal and limestone over a range of loads.

These pilot plant tests in San Diego supported the original Goodrich conclusion that the boiler currently being installed at Henry will meet all emissions requirements while burning high-sulfur Illinois coal.

ILLINOIS PARTICIPATION

The State of Illinois, with over 180 billion tons of identified coal reserves, and the largest reported bituminous coal resources of any state, would realize significant economic benefits from increased coal production. A number of important factors favor expanded coal development in the State, including the high heating value and relatively low production costs of Illinois coal, proximity to major markets and transportation networks, and availability of abundant water resources in Illinois.

The most significant factor limiting the use of Illinois coal is high sulfur content. State coal development efforts are therefore directed at technologies capable of solving the sulfur problem. The State's Department of Energy and Natural Resources had implemented a comprehensive program which includes funding for advanced physical and chemical coal cleaning, improved coal conversion and combustion systems, and new flue gas desulfurization technologies. The Goodrich circulating FBC boiler project is an important part of these initiatives.

Illinois Coal Bond Fund

The State is prOViding partial funding for the Goodrich boiler through the Coal Bond Fund, which supports the commercial-scale demonstration of promising new coal-use technologies. With over $36 million from the Bond Fund, Illinois is currently participating in six demonstration projects. This represents State partnership in over $275 million of capital projects at utilities, industries and institutional facilities.

The Henry boiler is one of three industrial-scale demonstrations receiVing support from the Bond Fund. Each highlights an advanced boiler technology designed for highly effective pollution control as well as for the efficiency, reliabiiity and ease of operation required in a modern industrial facility.

While only about 10 percent of the Illinois coal produced is currently consumed by industry, the industrial sector represents a significant potential market. The Department of Energy and Natural Resources has estimated that the commercial penetration of new coal technologies in only 10 percent of the Illinois industrial facilities now using oil or gas could mean 2,500 to 4,000 new jobs and nearly $750 million in additional annual income to the coal industry in the State within a relatively short time. The projected fuel cost savings to Illinois industries could exceed $1 billion annually by 1995. By sharing in the capital costs of first-of-a-kind technologies, which are generally higher than for conventional

831

ESL-IE-84-04-144


pl~nts. the State can help ensure that new ideas and technical concepts for using high-sulfur coal will progress to commercial use.

Project Selection The State selected the Goodrich project for funding support based on an extensive analysis of technology and site-specific factors. The evaluation focused on the innovative aspects of the proposed technology, areas of technical and management risk, capital and operating cost factors and the potential for commercial adoption of the technology by other industrial users. The benefits of the project to the locai and regional economies were also taken into consideration.

The evaluation identified a number of significant factors in support of the Henry boiler.

The circulating FBC boiler was found to be an ~dvanced second-generation system which had not yet been demonstrated at commercial scaie in the United States. The technology offered the potential for highly effective control of sulfur and NOx , as well as efficiency, reliability, ease of operation and quick response to load changes.

The system was sufficiently developed to present an acceptable levei of risk for the State and for Goodrich, and the project economics were acceptable with the addition of the State grant.

The size of the proposed boiler was comparable to the majority of industrial boilers in the State. The results of the demonstration project could therefore be meaningfully transferred to the industrial community.

The project had substantial local and regional economic benefits from plant construction and increased coal and limestone sales.

An additional factor which increased the State's confidence in the project was the reputation of the BFGoodrich Company as an outstanding corporate citizen with a history of safe, environmentally sound operations in

Illinois. The Company has a good project management approach and a strong background n the development and implementation of comple and innovative projects. Role of the State

The grant of $4.3 million to Goodrich is provIded as reimbursement for a portion of t e capital costs of the project during engineer g and construction of the boiler system. For ~ts participation, the State is allowed access t operating and cost information which will be distributed to the industrial community. Illinois will not seek ownership rights to plant or equipment purchased using State funds.

The State participates in the project by providing technical support throughout projec development and demonstration. Staff of the Department of Energy and Natural Resources review monthly schedule and cost reports, monitor the project to assess technical performance, economic viability and environmental acceptability, and attend periodic project meetings. Project monitori will continue through the end of the three-ye r demonstration phase.

Goodrich Commitments

As part of the terms of the grant agreement, Goodrich will collect and provide the State with information on the project during construction and for a three year period following start-up. During this period, various tests will be conducted to optimize t e boiler and evaluate its capabilities. The information collected will be organized into annual reports including operating and cost information. These reports will be made available by the State to other interested boiler operators. Goodrich has also agreed t assist the State in publicizing the project a its results through participation in technical meetings and seminars. After the boiler is operating, the State with the cooperation of Goodrich, will arrange inspections by interested boiler operators.

This program of collecting and disseminating information on the circulating FBC boiler should help to stimulate the demand for Illinois coal for industrial boiler fuel through the use of this innovative new technology for the use of high-sulfur coal in an enviromentally acceptable fashion.

832

ESL-IE-84-04-144


Documents

ESL-IE-84-04-1441