DOE/MC/16230-155

RIVESVILLE MULTICELL FLUIDIZED-BED BOILER

Quarterly Technical Progress Report for the Period july-September 1980

Work Performed Under Contract No. AC21-81 MC16230

Pope, Evans and Robbins, Incorporated New York, New York

DISCLAIMER

This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency Thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.

DISCLAIMER

Portions of this document may be illegible in electronic image products. Images are produced from the best available original document.

DISCLAIMER

"This book was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof."

This report has been reproduced directly from the best available copy.

Available from the National Technical Information Service, U. S. Department of Commerce, Springfield, Virginia 22161.

Price: Printed Copy A02 Microfiche AOl

RIVESVILLE MULTICELL FLUIDIZED-BED BOILER

Prepared by

Pope, Evans and Robbins, Incorporated

Quarterly Technical Progress Report

For the period July - September, 1980

Prepared for

UNITED STATES DEPARTMENT OF ENERGY Morgantown Energy Technology Center

Morgantown, West Virginia

Under .Contract No. DE-AC21-81MCI6230

DOE/MC/16230-15 5 Distribution Category UC-90e

ABSTRACT

The·objective of this· program is t6 design, construct and te.st ·a .mul ticellc fluidized-bed bt>iler as a· pollution-free me i:Jwd o-t: burning high-sulfur or highly: ·corrosive coals without execs·· sive maintenance problems-~ Tbe".f1uidized-bed boiler will pn)vi..Je approximately 300,000 pounds pf'-?team per hour. Steam pres sun~ and temperature. conditions were. -?elected to meet ·requirements of the site at which the boiler was:·,'installed·.·

i

TABLE 0~ CONTENTS

ABSTRACT. i . ...

l '

:. . . . : .... : .. •· .. r.· iii LIST OF EXHIBITS

INTRODUCTION . ~ i ,.,

1

SECTION

1.0 SUMMARY 2

1.1 Rivesville Multi-cell Fluidized Bed (MFB) 2

1.2 Subcontract Activities (Stone & Webster Engineering Corporation) · 2

1.3 Review of SignifiGant Events (Rivesville MFB) 3

1.4 Future Planning 3

2'. 0 RIVESVILLE HFB PLANT OPERATIONS 4

2.1 General 4

2.2 C-Cell Airflow Tests ·1

2.3 Feed Systems 4

2.4 Electrostatic Precipitator ~-:)

2.5 Operator Training 5

2.6 Bed i'·1aterial Modification •J

ii

LIS~ OF EXH~aiTS

Exhibit I - Composite Systems

Exhibit II .,.. Air and Flue Gas System

Exhibit III Feedwater and Steam System

Exhibit IV Coal and Limestone Feeding System

Exhibit v Fly ash Reinjection System

Exhibit VI Bed Material Removal System

iii

INTRODUCTION

General

The Government, in order to implement research and development work on a multicell fluidized-bed boiler operating under utility electric power generation conditions, awarded DOE/ERDA/OCR Contract No. EX-76-C-01--1237 to Pope, Evans and Robbins Incorporated (PER) on October 5, 1972. The work under this contract is a follow-up to work previously performed by PER under OCR Contract No. 15-01-0001-478 as amended, and OCR Contract No. 14-02-0001-12?.9 which indicated that continued development would have a high prob­ability of success.

Tasks and Phases

The objective of the program covered by DOE Contract No. EX-76-C-01-1237 is to test ~ multicell fluidized bed boiler as a pollution-free method of burning high-sulfur coals or highly corrosive coals without excessive maintenance.

The objective is to be accomplished by .designing, constructing and operating a multicell fluidized-bed boiler under utility electric power generation conditions in four technically dis­tinct but chronologically overlapping phases:

Phas~ I

Phase II

Phase III

Phase IV

MFB Boiler and Plant Design; Performance of Experiments in the Alexandria, Virginia Laboratory to Optimize MFB Boiler Perforrndnce.

Fabrication, Installation and Shakedown Status Operation.

Demonstration Operation under so2 Acceptor I-1ode.

Preparation of Design and Operation Manuals and design of a factory-assembled industrial MFB unit.

This quarterly report covers work performed under Phase I, ITI and IV of the contract in the period July, August and September 1980.

1

1 • 0 SUMr1ARY

1.1 Rivesville Multi-Cell Fluidized Bed CMFBl

Lirni ted testing was performed in the July-$eptembez;- period to de-. termine the cause of poor combust~on inC-cell but it was not·. ascertained. The Fuller~Kinyon screw pump coal feed system was' tested to determine its coal feed distribution characteristics and to note the resulting partie!~ size degradation, the latter being severe. Testing .of the eduqtor feed system with the MFB unit in simulated operating mode.indica:ted good coal distribution, little size distribution, and good overall performance. $orne electrostatic precipitator (ESP) test~ng was conducted.

The Rivesville·operator training curriqulum was updated and. tri­metric drawings of the various MFB engineering systems were pre­pared and incorporated into the curriculum.

Modification to the bed material handling system seemed to improve the performance of the system. ·

Summary Of Operating Hours

Q':l_?rter

CBC (Light off oil fired burners) 14.9

CBC (Coal fired) 109.4

C.: ell c.: 64.4

Cell B 16.9

Cell A 0

Commercial Mode· 12.5

1.2 Subcontract Activities (Stone & Webster Engineering Corporation)

To Date ·-· ~-···--·-·--

1859.7

4~)01.4

/.1)28.2

1148.5

5.8

906.7

Operations assistance and eng~neering design support of ·the Rivesville MFB has continueq. Emphasis this quarter has been given to ESP~ C-cell airflow maldistribution ~rosion, ~nd feed system testing.

A procedure to handle a prectpi tator transformer polY:-ch lorina tt::·.d- . bi-phenyl leak was offered.

· An engineering assessment and design analysis is underway for p::,ssible grid plate modifications to channel more air alc)ng

2

waterwalls (C-cell) • The design goal being to avoid tube wall erosion and to j..mprove combustion.

1.3 Review of Significant Events (Rivesville MFB}

July 28-31

August· 11-15 ..

August 18-22.,

A~gust 25-29

September 8-12

0 ••••

Operated'MFB in normal mode conducting pre­. cipi tator a.nd Fulle;r,...Kinyon tests. ·

Operationa} tests with unit "cold" were con­ducted inclbding Fuller-Kinyon sp~itter dis­tribution·tests and erosion assessment, C-cell air flow di~tribution tests, and eductot feed ttibe:tests·on south side of C-cell.

Performed distribution -tests on ·both sides . (North. apd ·south): ·of C-cell.

Conducted eductor coal flow distribution t~sts.

Operated MFB to deplete coal in No. 2 bunker.

1.4 Future Planning

An assessment of the Rivesville Program and development of a tes~ plan for the next fiscal period commenced.

3

2. 0 RIVESVILLE .HFB PLANT OPERATIONS

2.1 General

Most of the data takeri in this period deals with testing of various engineering systems of the MFB and an attempt to improve individual system perfor~ance with a goal of achieving in the.next fiscal period excellent overall performance. The testing done in this period will be summarized in this;report. The test data taken in· the January through December 1980 ·period is being carefully assessed and the plan is. to prese·nt and explain it in greater de­tail in the. next quarterly report, October-December 1980.

1.·

2.J C-Ccll hirflow Tc~t~

In previous C-cell testing, an imbalance in the coal feed or air feed was suspected of causing the inefficient combustion noted in that cell. Cold air flow tests were conducted in the cell and in cold tests (no fire or bed material) air maldistribution was in­deed noted. Possible cause was attributed to the design and geometry of the damper and plenum.

To help quantify the air distribution patterns three S-type pitots were installed.below the gridplate of C-cell. This would help· determine if an apparent air maldistribution during "cold" testing without bed material had any relationship to normal "hot" opera­tion.

Subsequent testing with the MFB in normai operating mode showed an average difference in static pressure between the west and east side bf C cell of about 0.5 inch~s of water. If this obser­vation can be translated into normal operation, it represents a 1-2 percent difference ·in flow through the gridplate between west and east sides of C-cell. Reasons other than maldistributioh ·of air below the grid-plate must be the cause of poor combustion in C-cell. Factors such as coal distribution, amount of fines, directional airflow above the gridplate, or volume of excess air should and are being considered as probable causes for poor C-c~ll combustion efficiency.

2.3 Peed Systems

The Fuller-Kinyon system was tested for coal feed distribution cLaracteristics and to note size degradation. Some negative t:c,parture from base line (December 197'9) test data was noted. Individual needle flows varied an average of 13 percent from rn~dian. Particle size degradation was severe.

'I'he new ·eductor feed system was tested in September and the results of that test are ~ncoura~ing. Tests were conducted with the MFB in simulated operating mode. Good coal distribution, little size

4

degra~ation, and good ove~all performance was noted. Future testing may show that, compared to the Fuller,...Kinyon ~crew pump, the eductor utilized half the horsepower for a much lower cost.

2.4 Electrostatic Precipitator

With the MFB operating in a normal test mode, g~s temper~tures were.monitored in the precipit-ator. L~rge temper~ture differences {200°F) were observed between thermocouples. Cause is only prbb­able. If these temperature diffe~encea can be attributed to flow patterns, then it seems reasonable to assume flow went from south to north.in the A and B sections of the ~recipit~tor~ As the precipitator was under high negative pressure (minus five inches of wate~l, the temperature differences might be attributed to suspected inward air leaks. To determine ·cause of these tempera­ture differences a leak test is planned and monitoring of the temperature in the precipitator will be continued in future tests.

J .~ \

2.5 Operator Training

The back-fit activities at Rivesville continue to improve the reliability of individual engineering system and thus the overall reliability of the entire MFB unit. Realizing that at Rivesville significan~ testing is possible and anticip~ting an intensive testing program in the next fiscal period it was felt that emphasis should be given to operator training. Besides improving engineer­ing system·s, anbther· way to achieve overall system reliability is by improving the performance of plant operators.·

The Rivesville operator training program is therefore being up­dated and special trimetric training pictorials have beeri pre­pared {Exhibits I, II, III, IV & V) and incorporated into the curriculum.

2.6 Bed M~terial Modification

In July the bed material storage tank {BMST) cyclone was put in ·series with the ash cooler cyclone. Flow was from ash cooler cyclone to BMST cyclone. Noting that the BMST cyclone was filled with hydrated, solidified bed material blocking flow, it was cleaned and its subsequent operation monitored. Downstream, only a very fine carryover was seen and then only for short periods of about one ~econd eyery 30 to 40 seconds. · Probable cause is o::.)eration {opening and closing) of the i3MST lock hoppers with the leakage being through the equalizing valve and into th~ vent. The :3~'stem will deserve moni taring during subsequent operating runs but our feeling is the probl~m has been resolved for p~rposes of operating to cohtinu~ gerteral system testing.

5

Though no data was t~ken, c~s~al observations during the September .8-12 run seemed to indicate that the modified system was operating satisfactorily, The system will be given attention on fut~re runs to insure reasonable operat~on. However, due to high priority items, no rigorous test-plan, data collection or data arialysis of the bed material syste~ is contemplated at this time.

6

2

I I

AIR AND FLUE GAS SYSTEM

FOPE. EVANS ,A.ND HOBBINS

8

1il70·0·

1~f s' ·i'

1~s~-o·

1010-o"

s:;o-o

S7~·o" ·sc.i-1d'

I '" ' :'·o"

- "- ~=- · ~ I

.-•

~-

Exhibit 3

• I i !

F'EED WATER A~D STEMi SYSTEM

POPE. EVANS AND RO:SE:tNS

9

7

Exhibi t 4

COAL AND LIMESTONE FEEDING SYSTEM

POPE. EVANS AND ROBBINS

10

107ll·d

105~--

tOsd·d'

10ld-d'

tot d-o

97d,-d' 967-to"

950-tci gsd-o

67J ·0 7

Exhibit 5

l"LYASH REINJECTION SYSTEM

POPE. EVANS AND ROBBINS

11

1!170·0 1~5-8

1030-0

9~-o·

sni-o. 9~7-10

r ~\l:t

SJ0-0

1 s:j-o

I I

i I

~ "! ·iJ· I • r ' , . ..J

Exhibit 6

' BED HA'i'ERIAL REMOVAL SYSTEM

POPE. EVANS AND ROBBINS

12

1070-0

106~-tr

1050-0

1030-0

101d- d'

L 990·0

nci o. 967-10

. 950-10. · s5r:Hf

.:Hi-u·

. -~- o· -c :·-o·