EPA-650/2-75-057-J

Octobei 1975
Environmental Protection  Technology Series
                                                   RVEY
                                         OF  FLUE  GAS
                      DESULFURIZATION  SYSTEMS
                      REID GARDNER STATION, NEVADA POWER CO.
                                        U.S. Environmental Protection Agency
                                         Office of Research and Development
                                              Washington, D. C. 20460

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                                      EPA-650/2-75-057-J
                SURVEY
           OF  FLUE  GAS
DESULFURIZATION SYSTEMS
REID GARDNER STATION, NEVADA POWER  CO.
                    by

     Richard W. Gerstle and Gerald A. Isaacs

      PEDCo-Environmenlal Specialists, Inc.
           Suite 13, Atkinson Square
            Cincinnati, Ohio 45246
        Contract No. 68-02-1321, Task 6]
             ROAP No. 21AXC-130
          Program Element No. 1AB013
       EPA Project Officer:  Norman Kaplan

    Industrial Environmental Research Laboratory
     Office of Energy, Minerals, and Industry
    Research Triangle Park, North Carolina 27711
                Prepared for

   U.S. ENVIRONMENTAL PROTECTION AGENCY
       Office of Research and Development
           Washington, D. C. 20460

                October 1975

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                       EPA REVIEW NOTICE

 This report has been reviewed by the U.S.  Environmental Protection
 Agency and approved for publication.  Approval does not. signify that
 the contents necessarily reflect the views'and policies of the Environ-
 mental Protection Agency, nor doe's mention ,of trade names or commer-
 cial products constitute endorsement or recommendation for use.
                  RESEARCH REPORTING SERIES

Research reports of the Office of Research and Development, U .S . Environ-
mental Protection Agency, have been grouped' Into7 series'. • These'broad
categories were established to facilitate further development and applica-
tion of environmental technology.  Elimination of traditional grouping was
consciously planned to foster technology transfer and maximum interface
in related fields. These series are:

           1.  ENVIRONMENTAL HEALTH EFFECTS RESEARCH

           2.  ENVIRONMENTAL PROTECTION TECHNOLOGY

           3.  ECOLOGICAL RESEARCH

           4.  ENVIRONMENTAL MONITORING

           5.  SOCIOECONOMIC ENVIRONMENTAL STUDIES
           6.  SCIENTIFIC AND TECHNICAL ASSESSMENT REPORTS
           9.  MISCELLANEOUS

This report has  been assigned to the ENVIRONMENTAL PROTECTION
TECHNOLOGY series.  This series describes-research performed to
develop and demonstrate instrumentation, equipment and methodology
to repair or prevent environmental degradation from point and  non-
point sources  of pollution. This work provides the new or unproved
technology required for the control and treatment of pollution sources
to meet environmental quality standards.
This document is available to the public for sale through the National
Technical Information Service, Springfield,  Virginia 2216! .
                 Publication No. EPA-650/2-75-057-J
                               11

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                      ACKNOWLEDGMENT




     This report was prepared under the direction of Mr.



Timothy W. Devitt.   The principal authors were Mr. Richard



W. Gerstle and Dr.  Gerald A. Isaacs.  Mr. Charles D. Fleming



was responsible for editorial review and preparation of



graphic materials.



     Mr. Wade H. Ponder, former EPA Project Officer, had



primary responsibility within EPA for this project report.



Information and data on the plant operation were supplied by



Mr. David G. Barneby, Nevada Power Company, by Mr. R. S.



Sommer, Combustion Equipment Associates, Inc., and Mr. D. C.



Philp, Bechtel Corporation during and subsequent to the



plant survey visit.



     The authors appreciate the efforts and cooperation of



everyone who participated in the preparation of this report.
                              111

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                                             November 20, 1975
                        ERRATA
Page vii --At end of 8th line from bottom of page:  change "have not"
             to read "have."

Page B-5 --In 7th line of block 16. ABSTRACT: change "did not meet"
             to read "met."
(Please make the above two changes in your copy of:
   EPA-650/2-75-057-J, Survey of Flue Gas Desulfurization Systems;
        Reid Gardner Station, Nevada Power  Co. ,  October 1975)

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                       TABLE OF CONTENTS


                                                      Page

ACKNOWLEDGMENT                                        iii

LIST OF FIGURES                                       vi

LIST OF TABLES                                        vi

SUMMARY                                               vii

1.0  INTRODUCTION                                     1-1

2.0  FACILITY DESCRIPTION                             2-1

3.0  DESULFURIZATION SYSTEM                           3-1

     3.1  Process Description                         3-1

          3.1.1  Flue Gas Flow                        3-1
          3.1.2  Liquor Flow                          3-4

     3.2  Design Parameters                           3-6

     3.3  Installation Schedule                       3-8

     3.4  Cost Data                                   3-8

4.0  FGD SYSTEM PERFORMANCE                           4-1

     4.1  FGD Problems and Solutions                  4-1

APPENDIX A  PLANT SURVEY FORM                         A-l

APPENDIX B  PLANT PHOTOGRAPHS                         B-l
                                 V

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                       LIST OF FIGURES
Figure

 3.1



 3.2
Simplified Flow Diagram of FGD System,
Reid Gardner Station - Nevada Power
Company

Liquor Flow System - Reid Gardner FGD
System
Page

3-2



3-5
                       LIST OF TABLES
Table
 2.1
 3.1
Pertinent Data on Plant Design, Operation
and Atmospheric Emissions - Reid Gardner
Station
2-3
Typical Pressure Drop Across FGD Components  3-8
                              VI

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                           SUMMARY




     Flue gas desulfurization  (FGD) systems have been designed



and installed to control sulfur dioxide and particulate



emissions from two existing 125 MW generating units at the



Reid Gardner Station of Nevada Power Company  (NPC).  Two



additional 125 MW units, originally planned for installation



in 1976 and 1977, are to incorporate similar FGD equipment.



The installation of the second new unit has been indefinitely



postponed.



     The FGD systems utilize a sodium carbonate scrubbing



process developed, designed and supplied by Combustion



Equipment Associates, Inc. (CEA) and its joint venture



partner, Arthur D. Little, Inc. (ADL).  Bechtel Corp. performed



the architectural/engineering work for the systems.  The



systems were placed in operation in April 1974, and have not



met S02 and particulate performance guarantees during the



first year of operation.  Each system utilizes twin parallel



Venturis followed by an absorber tower.  As of August 1,



1975, System 1 had operated for 3814 hours and System 2 had



operated for 2947 hours.  Potential availabilities for the



systems seem to be near 100 percent, but the plant has not



had access to an adequate supply of trona, a sodium carbonate

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ore that constitutes the scrubbing medium.  Alternate sodium

carbonate sources recently have been secured.  Pertinent

operational data are summarized in the following table.
       SUMMARY OF FGD DATA, REID GARDNER UNITS 1 AND 2
Unit rating, MW  (net)

Fuel

   Gross heating value, BTU/lb

   Ash, percent

   Sulfur, percent

FGD process design



Process


New or retrofit

Start-up date

FGD modules

Efficiency, percent

   Particulates
     Scrubber and multicyclone

   so2

Make-up water, gpm/MW

Disposal

Unit cost, $/KW  (net)
110'

Coal

12,500

9

0.6

Combustion Equipment
Associates Inc./
Arthur D. Little, Inc.

Aqueous sodium carbonate
scrubbing

Retrofit

April 1974

One per unit
99+

90+

1.3

Evaporation ponds

50
                             Vlll

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                      1.0  INTRODUCTION




     The Industrial Environmental Research Laboratory (formerly



Control Systems Laboratory)  of the U.  S. Environmental



Protection Agency (EPA)  has initiated a study to evaluate



the performance characteristics and degree of reliability of



flue gas desulfurization (FGD) systems on coal-fired utility



boilers in the United States.   This report on the Reid



Gardner Station of Nevada Power Company (NPC) is one of a



series of reports on such systems.  This report presents



data on key process design and operating parameters, describes



the major start-up and operational problems encountered at



the facility and the steps taken to alleviate such problems,



and identifies the total installed and annualized operating



costs.



     This report is based upon information obtained during a



plant inspection on October 8, 1974, and on data provided by



NPC and Combustion Equipment Associates, Inc. (CEA).



     Section 2.0 presents pertinent data on facility design



and operation.  Section 3.0 describes the FGD system, and



Section 4.0 analyzes FGD system performance.  Appendices



present details of plant and system operation and photos of



the installation.
                             1-1

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                  2.0  FACILITY DESCRIPTION




     The Reid Gardner Station of NPC is located near Moapa,



Nevada, about 50 miles northeast of Las Vegas.  This is a



sparsely populated, arid part of Nevada.  The station has



two electric power generating units, (Reid Gardner Units 1



and 2) each rated at 125 MW (gross).



     Both units are identical in design and operate under



base load conditions.  The pulverized-coal-fired boilers



were manufactured by Foster-Wheeler.  Unit No. 1 was placed



in service in 1965 and Unit No. 2 started operation in 1968.



Utah coal is burned, having an average gross heating value



of 12,500 BTU/lb and average ash and sulfur contents of 9



and 0.6 percent, respectively.



     Reid Gardner Unit 3 is presently under construction



with a start-up date scheduled for 1976.  Its design capacity



is 125 MW.  Reid Gardner Unit 4 was in the planning stage



but has been indefinitely postponed.



     Enforcement action by Clark County in 1970 led NPC to



contract with Bechtel Corporation for design and instal-



lation of an FGD system.  Bids for FGD systems were solicited



in 1971.  CEA was the only vendor that proposed a soluble



reagent  (sodium carbonate) scrubbing medium, and they were
                              2-1

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selected for the work.  In early 1972, CEA/ADL designed,



built and operated a 7000 to 9000 acfm pilot unit at the



plant to better define operating variables using less



expensive trona as a source of sodium carbonate.  Two full-



scale scrubbers were placed in service in April 1974.  Table



2.1 summarizes pertinent data for the boilers and the



atmospheric emissions.



     Clark County, Nevada limits SO- emissions to 0.15 Ib/MM



BTU input.  The State of Nevada limits SO- emissions to 0.21



Ib/MM BTU input.
                              2-2

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                   Table  2.1   PERTINENT  DATA  ON  PLANT  DESIGN,  OPERATION AND


                          ATMOSPHERIC  EMISSIONS - REID  GARDNER  STATION
Boiler data
Rating generating capacity, MW (gross)3
Average capacity factor (1973), %
Boiler manufacturer
Year placed in service
Maximum coal consumption, ton/hr
Maximum heat input, MM BTU/hr
Stack height above grade, ft
Flue gas rate - maximum, acfm
Flue gas temperature, °F
Emission controls
Particulate
so2
Particulate emission rate
Allowable, Ib/MM BTU
Actual, Ib/MM BTU
SO- emission rate
Allowable, Ib/MM BTU
Actual, Ib/MM BTUC
1
125
73
F-W
1965
47.5
1187.5
200
473,000
350

Multicyclone and
venturi scrubber
Venturi scrubber
and absorber tower

0.12
0.055
0.15
0.115
2
125
73
F-W
1968
47.5
1187.5
200
473,000
350

Multicyclone and
venturi scrubber
Venturi scrubber
and absorber tower

0.12
0.55
0.15
0.115
N)
I
LJ
         Net without scrubber is 112 MW.  With  scrubber  and  reheat,  net  is  106.5  MW.

         Calculated value.

         Based on 84% removal efficiency  (310 ppm inlet,  50  ppm outlet)  and  a  0.72  Ib/MM  BTU
         inlet concentration.

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                 3.0  DESULFURIZATION SYSTEM




3.1  PROCESS DESCRIPTION



     The sodium carbonate based FGD systems on Reid Gardner



Units 1 and 2 were placed in operation in April 1974.  The



design of these systems was based on data gathered from the



operation of an 8000 acfm pilot plant which operated at the



Reid Gardner Station during 1971 and 1972.



     The FGD system on each boiler consists of a single



module, designed to handle 473,000 acfm of gas at 350°F.



The module is made up of two parallel variable throat



venturi scrubbers followed by a single-stage perforated



plate washing tower.  The FGD modules on both boilers share



a common trona (sodium carbonate ore) storage and beneficia-



tion system.  Beneficiation consists of settling out in-



solubles (mainly sand) in a clarifier.  Bypassing of each



module is possible through the use of leaf and guillotine



isolation dampers.



3.1.1  Flue Gas Flow



     As shown in Figure 3.1, the hot flue gas from the



boiler passes through an existing mechanical collector



(multicyclone) where about 75 percent of the fly ash is



removed.  The flue gas is then drawn through a 3000 hp fan
                              3-1

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                                                    DESIGN
                                             5°F     AM3IENT
                                          67,000 acfm AIRi   ,A
u>
I
NJ
473,000 acfm
350°F



ASH
EVAPORATION
t
SETJL.JNG
r

ASH REKOVAL
SYSTE!':
A



WATE
MUDC
STORAGE
TANK
I
COOLING
TO'.-JEiiS
WAT
R FROM
Y RIVER
STr
I
BYPASS
DAMPER ;
^
•) (f^
f ISOLATION ]
( DAMPER, 169°F ill9°F
' 486,000 acfm
X
3000 hp
ISOLATION BOOSTER
DAMPERS /— ,FAN
	 ^ 	 ^^ 1 1
,.., — A ID AD AM ri
PECH^CAL ^SuRis
| COLLECTOR \ /
'
i - *..'

BOILER £ E
•S «


i_j
TRO.NA SILO *°

pH 11

MIXING TANK g:;i V^
v ^'|g


CLARIFIER — *J
\x



<:
' 'S1^
474 psia
476.7 Ib/min
364,400 acfm
j
/^
DEMI


\
k

l}
«E
i
"1
'j
•>


\.
STER
~TRAT

/
f« 5


•z.
LiJ
31
Q.
cn
1 °
1 0
VENTURI
RECYCLE
TANK

^LS
* ' f^ \ _ 	

ER FROM
WELLS
^ PO
NEUTRAL
TA

ST-
[ZAT
NK.
ION
Y ^


UJ ,
CJ3
o:
^ pH 11
•^ MAKE-UP WATER FROM ASH POND
3_ . '•* . 129 gpm 1
o> • J6 gpm
0 ' 4r
ro TRAY
\ /RECYCLE
\X TANK
[ALKALI


'I : SEiTLING FVAPOWTTf^J
pH-7
50 gpm
POND POND

              Figure 3.1   Simplified flow diagram of  FGD system, Reid  Gardner Station -

                                          Nevada Power  Company.

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after which it splits into two streams and enters the twin



throat venturi scrubber.  Here the hot flue gas is quenched



with circulated scrubbing liquor sprayed from tangential



nozzles located on the walls of the venturi.  The gas-liquid



mixture then passes through the venturi throats and exits



into a sump, where the reduction in velocity causes the



liquor droplets to fall and separate from the gas stream.  A



liquid-to-gas ratio  (L/G) of 10 gal./lOOO acf of gas at



1.30°F and a pressure drop of about 15 inches of water are



maintained in the venturi for efficient removal of SO_ and



particulates.  The rectangular venturi throat opening is 18



inches wide by 18 feet long.  The scrubbed gas at a tempera-



ture of 130°F then tangentially enters the cylindrical



droplet separator tower.  The centrifugal force created by



the tangential flow causes the finer droplets to coalesce



near the tower's wall and separate from the gas stream.  The



scrubbed gas rises through the tower and bubbles through



3/16 in.-diameter holes in a single sieve tray.  The tray is



flooded with clear water from the ash pond at a rate equiv-



alent to 1 gpm per 1000 acfm of gas.  This tray is inter-



mittently washed with fresh water sprayed against the tray



bottom.  More SO- is absorbed in the sieve tray and the pH



of the tray liquid drops from 6.2 to about 5.  The cleaned



gas continues up the tower and passes through a single-pass,



horizontal radial vane-type mist eliminator where entrained



liquid droplets are removed.  The vanes are type 316L stainless



steel.  No demister washing is provided.





                           3-3

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     In or.de.r to give buoyancy to the gas and to prevent



condensation on the duct and stack walls, the gas is re-



heated by direct mixing with hot air.  This hot air is



generated by drawing ambient air through a separate fan and



indirectly heating it in a finned tube heat exchanger using



steam.  The combined gas stream enters a 200-foot tall stack



and is.discharged to the atmosphere.



3.1.2  Liquor Flow



     The FGD system water is supplied from the ash settling



pond  (see Figure 3.1).  This water is originally supplied to



the cooling towers from wells and from the Muddy River.



Trona, a low grad ore containing 60 percent sodium carbonate,



20 percent sodium chloride, 10 percent insolubles, 10 percent



sulfates and inert dissolved solids, is normally used as the



SO- scrubbing agent.  Trona is shipped to the Reid Gardner



Station in powdered form.  The trona is transferred pneumatically



to a silo having a 3-day storage capacity.  From there it is



conveyed to a slurry tank and mixed with water from the ash



ponds to dissolve the sodium carbonate.  The slurry, containing



such impurities as sand and sodium chloride, is mixed with a



portion of the supply water and is pumped to a clarifier



where insoluble impurities settle out.  The clarified sodium



carbonate liquor is injected into the venturi recirculation



loop..  The remainder of the make-up water (pH 11) is injected



into the absorber circuit via the tray recycle tank.  Slowdown



from the venturi recycle tank is mixed with the alkaline
                              3-4

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clarifier underflow stream and adjusted to pH 7 in the post-



neutralization tank.  The spent liquor from the post-neutra-



lization tank amounts to about one percent of the recycle



liquor flow through the venturi and absorber.  The spent



liquor is pumped to a 6-acre ash settling pond, and the



overflow from this pond flows to a 45-acre evaporation pond.



No liquor is recycled to the modules from these ponds.  This



method is appropriate for the disposal of spent liquor in



Nevada because of the low relative humidity in that area.



All make-up water is supplied from the ash settling pond.



3.2  DESIGN PARAMETERS



     Design details of this scrubbing system are proprietary



to CEA.  The system chemistry is based on the following



reactions:
     Na2S03 + SO2 + H20  -»•  2NaHSO3



The first reaction predominates so that there is little



NaHSO, in the absorber effluent.  Alkaline constituents in



the make-up water entering the sieve tray also aid the



absorption of S02 .  A pH of approximately 6.2 is maintained



in the absorber inlet liquor.   It is reported that 0.8 to



0.9 moles of Na2C03 are used per mole of S02 removed.



     Make-up solution is fed at a rate of about 50 gpm into



the venturi recirculation loop.  Within this loop, about



5000 gpm of liquor (L/G=10) , is injected into the two venturi



scrubbers where fly ash and some SO- is captured.  A pressure
                              3-5

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drop of about 15 inches of water occurs across the venturi



at a throat velocity of approximately 165 ft/sec.  The liquor



is partially separated from the flue gas in the lower portion



of the '30-foot diameter perforated plate tower where the gas



velocity is reduced to approximately 11 ft/sec.  Liquor from



the bottom of this tower flows to a recirculation tank.  The



underflow from this tank is mixed with fresh solution and



recycled to the venturi scrubbers.  Underflow from the



recirculation tank which amounts to-approximately 50 gpm



(1%) is bled off to the ash settling pond.



     Flue gas passing upward through the perforated plate at



a temperature of about 130°F is contacted with liquor which



is recirculated at a rate of 600 gpm.  Wash water from the



tray recycle system is sprayed intermittently against the



bottom of this tray to prevent fly ash accumulation and to



provide make-up water to the venturi recycle loop.



     The venturi throats are fabricated of Incoloy 825 and



the balance of the system is constructed of rubber-lined



mild steel.  The demisters are fabricated from 316L stain-



less steel.



     Pressure drops through the various system components



are shown in Table 3.1.
                              3-6

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   Table 3.1  TYPICAL PRESSURE DROP ACROSS FGD COMPONENTS
Equipment
Venturi
Perforated Tray
Demister
Ductwork
TOTAL
Pressure
inches of
15
3
0.5
1.5
drop,
water




20
3.3  INSTALLATION SCHEDULE



     A request for bids for design and installation of an



FGD system was issued by NPC in mid-1971, and a contract was



awarded to CEA in late 1971.  A pilot plant was built and



operated in early 1972 and detailed engineering and design



were completed during that year.  Construction started on



both modules in December 1972.   The systems were started in



early 1974 and were in operation by March and April of that



year.



3.4  COST DATA



     Detailed cost breakdowns are not available.  The two



scrubbing systems along with all raw material handling and



pond equipment cost $11,000,000 or $50/KW (net).  Operating



costs have not yet been tabulated due to limited operation.
                             3-7

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                 4.0  FGD SYSTEM PERFORMANCE




     Since start-up in early 1974, both modules at the- Reid



Gardner Station have performed satisfactorily.  However,



because of difficulties in obtaining a sufficient quantity



of trona, the operation of the modules has been subjected to



frequent interruptions.  The FGD system has periodically



been bypassed to conserve trona.  As of August 1, 1975,



Module 1 had operated for 3814 hours and Module 2 had



operated for 2947 hours.



4.1  FGD PROBLEMS AND SOLUTIONS



     As noted above, the major problem in the continuous



operation of the FGD modules has been the lack of an adequate



supply of trona.  In order to solve this problem, various



alternate sources of sodium carbonate have been used and the



present absorbent supply is made up of numerous small supplies,



     The system had the usual start-up problems such as



rubber liners on recirculation lines becoming loose due to



poor fabrication, freeze-up of instruments and plugging of



control valve bypass lines.  Another minor problem included



excessive leakage in the recirculation pumps' seals.   Also



mechanical failure problems were experienced with the.
                            4-1

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guillotine dampers, which were later resolved with redesigned



drive train components.



     An intensive evaluation of problems is not possible due



to the fairly brief operating period.  However, the sim-



plicity inherent in an open-loop soluble system will naturally



minimize operating difficulties.  The overall water loop for



the plant is closed now that the scrubbers are operational.



The scrubber evaporation has reduced the net amount of water



going to the evaporation ponds as cooling tower blowdown -so



that the evaporation pond level is now stable and no water



is running out of the pond into any other groundwater systems.
                               4-2

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    APPENDIX A




PLANT SURVEY FORM
     A-l

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                    PLANT SURVEY FORM3

              NON-REGENERABLE FGD PROCESSES




A.  COMPANY AND PLANT INFORMATION

    1.  COMPANY NAME         Nevada Power Company	

    2.  MAIN OFFICE          P.O. Box 230. Las Vegas. Nevada  89151

    3.  PLANT MANAGER        A.T. (Al)  Perry	

    4.  PLANT NAME           Reid Gardner Station	

    5.  PLANT LOCATION       Moapa,  Nevada  89025	

    6.  PERSON TO CONTACT FOR FURTHER INFORMATION P.G.  (Dave) Barneby

    7.  POSITION                            Production Mechanical Engr.

    8.  TELEPHONE NUMBER                    (702) 385-5631	

    9.  DATE INFORMATION GATHERED           Form Completed Sept.23,1974

   10.  PARTICIPANTS IN MEETING                 AFFILIATION

        Dave Barneby	             	

        Terry Levitt	             Nevada Power	

        W.  H. Ponder                        U.S. EPA
        John Busik                          U.S. EPA
        R.W.  Gerstle                        PEDCo
        F.K.  Zada                           PEDCo
  These data were obtained from Nevada Power Co. on September
  23, 1974.  Some of the data have been updated in the text of the
  report.

                            A-2                  5/17/74

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B.  PLANT DATA.  (APPLIES TO ALL  BOILERS AT THE PLANT).
C.
CAPACITY, MW
SERVICE (BASE, PEAK)
FGD SYSTEM USED
BOILER NO.
1
120
Base
, Throw
Sodium
2
120
Base
Away
Carbonat



a








BOILER DATA.  COMPLETE SECTIONS  (C) THROUGH  (R) FOR EACH
              BOILER HAVING AN FGD SYSTEM.

 1.  BOILER IDENTIFICATION NO.         Reid Gardner No. 1

 2.  MAXIMUM CONTINUOUS HEAT INPUT     H58	   MM BTU/IIR

 3.  MAXIMUM CONTINUOUS GENERATING CAPACITY   126      MW (Gross)

     MAXIMUM CONTINUOUS FLUE GAS RATE.    473,000    ACFM  @ 350 °F

     BOILER MANUFACTURER              Foster Wheeler	

     YEAR BOILER PLACED IN SERVICE    1965	
     7.  BOILER SERVICE  (BASE LOAD, PEAK,  ETC.)  Base Load

     8.  STACK HEIGHT                            20°	

     9.  BOILER OPERATION HOURS/YEAR  (1973)      7032;06

    10.  BOILER CAPACITY FACTOR *                73%	

    11.  RATIO OF FLY ASH/BOTTOM ASH             80/20
      * DEFINED AS:  KwH GENERATED IN YEAR
                     MAX. CONT. GENERATED  CAPACITY IN KW x 8760  HR/YR
                             A-3
                                              5/17/74

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D.  FUEL DATA
    1.  COAL ANALYSIS  (as received)
             GHV  (BTU/LB.)
             S %
             ASH  %
MAX.
12,900
0.7
. 12
MIN.
12,000
0.4
6
AVG.
12,500
0.55
9
    2.  FUEL OIL ANALYSIS  (exclude start up  fuel)
             GRA'DE                      	
             s %                        	
             ASH %
E.  ATMOSPHERIC EMISSIONS
    1.  APPLICABLE EMISSION  REGULATIONS
        a)  CURRENT REQUIREMENTS
            AQCR PRIORITY CLASSIFICATION
            REGULATION & SECTION NO.
            MAX. ALLOWABLE EMISSIONS
            LBS/MM BTU
        b)  FUTURE REQUIREMENTS,
            COMPLIANCE DATE
            REGULATION & SECTION NO.
            MAXIMUM ALLOWABLE EMISSIONS
            LBS/MM BTU
PARTICULATES
     SO-


Clark County
Less than
Ring. 1 0.12


Clark Coui
0.15
New Plants
Clark County
Ringleman  0
New Plants
Clark County
  0.15
    2.  PLANT PROGRAM FOR PARTICULATES COMPLIANCE Completed
    3.  PLANT PROGRAM FOR SO2 COMPLIANCE
      Completed
                             A-4
                                                    5/17/74

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F.  PARTICULATE REMOVAL

    1.  TYPE

        MANUFACTURER
MECH.
Research
Co.
/ACTUAL 88/75
* LB/HR
GR/SCFD .7940
T.R/MMRTI1
E.S.P.





FGD
Comb. Equip
Assoc.


0.0197
0.055
        DESIGN BASIS, SULFUR CONTENT
                                                1.0%
G.  DESULFURIZATION SYSTEM DATA

    1.  PROCESS NAME

    2.  LICENSOR/DESIGNER NAME:

                       ADDRESS:

             PERSON TO CONTACT:

                 TELEPHONE NO.:
                               Throw away sodium carbonate	
                               Combustion Equipment Associates

                               555 Madison Ave.. N.Y., N.Y.
                               R. S. Sommer	
                               (212) 980-3700	
    3.  ARCHITECTURAL/ENGINEERS, NAME:   Bechtel Power Corp.

                       ADDRESS:    Norwalk,  California	

             PERSON TO CONTACT:    D.C.  Philp	

                 TELEPHONE NO.:     (213)  923-9761  Ext.  284
                                                     DATE
                                                     1971
4.   PROJECT CONSTRUCTION SCHEDULE:

    a)   DATE OF PREPARATION OF BIDS SPECS.  	

    b)   DATE OF REQUEST FOR BIDS                 1971

    C)   DATE OF CONTRACT AWARD                   1971

    d)   DATE ON SITE CONSTRUCTION BEGAN     Dec.  1972

    e)   DATE ON SITE CONSTRUCTION COMPLETED      1974

    f)   DATE OF INITIAL STARTUP           April  1974

    g)   DATE OF COMPLETION OF SHAKEDOWN          1974
     *At Max. Continuous Capacity
                            A-5
                                             5/17/74

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    6

    7

    8
    LIST MAJOR DELAYS IN CONSTRUCTION SCHEDULE AND CAUSES:

      Design changes	

      Additional pilot plant testing	

      Material delivery	

      Design errors	

      Labor disputes	

      Subcontractor delays	

    NUMBER OF S02 SCRUBBER TRAINS USED         	1
    DESIGN THROUGHPUT PER TRAIN, ACFM @ 350°F    473,000

    DRAWINGS:  1)  PROCESS FLOW DIAGRAM AND MATERIAL BALANCE

               2)  EQUIPMENT LAYOUT
H.  SO2 SCRUBBING AGENT

    1.   TYPE

    2 .   SOURCES OF SUPPLY
    5

    6,
                                        Pure or Impure
                                        Sodium Carbonate
                                        Morrison & Weatherly
                                        Kerr McGee  Chem.,  FMC Corp.,
3.  CHEMICAL'COMPOSITION (for each source)   Stauffer Chem.
    SILICATES

    SILICA

    CALCIUM CARBONATE

    MAGNESIUM CARBONATE

    EXCESS SCRUBBING AGENT USED ABOVE
    STOICHIOMETRIC REQUIREMENTS

    MAKE-UP WATER POINT OF ADDITION

    MAKE-UP ALKALI POINT OF ADDITION
                                            Max. '10% sand
                                            Max. 10% sand
                                                 NA
                                                 NA
Tray
Venturi
                             A-6
                                                 5/17/74

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J.  SCRUBBER TRAIN SPECIFICATIONS
    1.  SCRUBBER NO. 1
        TYPE   (TOWER /VENTURI)              Venturi
        LIQUID/GAS RATIO, G/MCF <§ 350°F     10
        GAS VELOCITY THROUGH SCRUBBER,  FT/SEC    (15"  AP)
        MATERIAL OF CONSTRUCTION                  Incolloy 825	
        TYPE OF LINING                            Rubber (Tri-Flex)
                                                  Bottom
        INTERNALS:
           TYPE  (FLOATING  BED,  MARBLE BED,  ETC.)	*?A	

           NUMBER OF STAGES                      	NA	

           TYPE AND SIZE OF  PACKING MATERIAL    	NA	

           PACKING THICKNESS PER  STAGED'

           MATERIAL OF  CONSTRUCTION,  PACKING:   	NA	

                                     SUPPORTS:	

        SCRUBBER NO. 2  *a'

        TYPE  (TOWER/VENTURI)	

        LIQUID/GAS RATIO, G/MCF @     °F          	

        GAS VELOCITY THROUGH SCRUBBER, FT/SEC   	.	

        MATERIAL OF CONSTRUCTION                 	

           TYPE  OF LINING                        	

        INTERNALS:

           TYPE  (FLOATING  BED, MARBLE BED, ETC.)	

           NUMBER OF STAGES                     	

           TYPE  AND SIZE OF PACKING MATERIAL   	
 a) Scrubber  No.  1  is  the scrubber that the flue gases first
    enter.  Scrubber 2 (if applicable) follows Scrubber No. 1.
 b) For  floating  bed,  packing thickness at rest.

                              A-7                 5/17/74

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4.
   PACKING THICKNESS PER STAGE

   MATERIAL OF CONSTRUCTION, PACKING:.

                            SUPPORTS:.

CLEAR WATER TRAY  (AT TOP OF SCRUBBER)

TYPE

L/G RATIO

SOURCE OF WATER

DEM1STER

   TYPE   (CHEVRON, ETC.)

   NUMBER OF PASSES  (STAGES)

   SPACE BETWEEN  VANES

   ANGLE OF VANES

   TOTAL DEPTH OF DEMISTER

   DIAMETER OF DEMISTER
                                          Sieve - 3/8" holes

                                          1 gal/1000 acfm g 350°F

                                          Ash pond	
                                          Radial vane
                                          Air foil
                                               30
       DISTANCE BETWEEN TOP OF PACKING
       AND BOTTOM OF DEMISTER

       POSITION  (HORIZONTAL, VERTICAL)

       MATERIAL OF CONSTRUCTION

       METHOD OF CLEANING

       SOURCE OF WATER AND PRESSURE

       FLOW RATE DURING CLEANINGS, GPM
                                           foA
                                      Horizontal
                                      SS  316L
                                      None
                                      None
                                      None
       FREQUENCY AND DURATION OF CLEANING None	

       REMARKS   3 concentric rings of vanes w/gutter collectors

       at outer edges.
5.   REHEATER

       TYPE (DIRECT, INDIRECT)
                                      Indirect
b) For floating bed, packing thickness at  rest.
                          A-8
                                              5/17/74

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       DUTY,  MMBTU/HR

       HEAT TRANSFER SURFACE AREA SQ.FT
       TEMPERATURE OF GAS:   IN 	   OUT +50°F @ 32° ambient

       HEATING MEDIUM SOURCE              Boiler Secondary  Super-
                                           heater
            TEMPERATURE & PRESSURE     	

            FLOW RATE                  	LB/HR

       REHEATER TUBES, TYPE AND
       MATERIAL OF CONSTRUCTION         Aerofin - Extended Surf.

       REHEATER LOCATION WITH RESPECT  TO DEMISTERFollowinq
       METHOD OF CLEANING	None

       FREQUENCY AND DURATION OF CLEANING None
       FLOW RATE OF CLEANING MEDIUM 	None     LB/HR

       REMARKS 	
6.  SCRUBBER TRAIN PRESSURE DROP DATA        INCHES OF WATER

       PARTICULATE SCRUBBER                  	

       S02 SCRUBBER
       CLEAR WATER TRAY                      	+3

       DEMISTER                              	+ -5

       REHEATER                              	Nil

       DUCTWORK                                    +1'5
       TOTAL FGD SYSTEM                      	+20
                         A-9                  5/17/74

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    7.
    8.
FRESH WATER MAKE UP FLOW RATES AND POINTS OF ADDITION

   TO:  DEMISTER        None	
                QUENCH CHAMBER  None
                ALKALI SLURRYING

                PUMP SEALS 	

                OTHER 	
                            "20 qpm  avg. 53 qpm max.

                        	I 6 gpm	

                        Wash tray 135 gpm	
                TOTAL
                             max.  190 gpm per unit
                                                          NA
   FRESH WATER ADDED PER MOLE OF SULFUR REMOVED

BYPASS SYSTEM

CAN FLUE GAS BE BYPASSED AROUND FGD SYSTEMS   Yes, @ 100% load

GAS LEAKAGE THROUGH BYPASS VALVE, ACFM 	Negligible
K.  SLURRY DATA
    LIME/LIMESTONE SLURRY MAKEUP TANK

    PARTICULATE SCRUBBER EFFLUENT
    HOLD TANK (a)

    SO2 SCRUBBER EFFLUENT HOLD
    TANK (a)
pH



%
Solids



Capacity
(gal)



Hold up
time



L.  LIMESTONE MILLING AND CALCINING FACILITIES:  INDICATE BOILERS
    SERVED BY THIS SYSTEM.
        TYPE OF MILL (WET CYCLONE, ETC.)

        NUMBER OF MILLS

        CAPACITY PER MILL

        RAW MATERIAL MESH SIZE

        PRODUCT MESH SIZE


                                A-10
                                                         T/HR
                                                  5/17/74

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                                             Mixing tank
                                             Ash pond
        SLURRY CONCENTRATION IN MILL

        CALCINING AND/OR SLAKING FACILITIES

        SOURCE OF WATER FOR SLURRY MAKE  UP OR
        SLAKING TANK

M.  DISPOSAL OF SPENT LIQUOR

    1.  SCHEMATICS OF SLUDGE & FLY ASH DISPOSAL  METHOD

        (IDENTIFY QUANTITIES OR SCHEMATIC)  	

    2.  CLARIFIERS  (THICKENERS)

           NUMBER                             2 clarifying ponds

           DIMENSIONS                         6 acres,  8 acres
       CONCENTRATION OF SOLIDS IN UNDERFLOW

    ROTARY VACUUM FILTER

       NUMBER OF FILTERS                	

       CLOTH AREA/FILTER                	

       CAPACITY                 	
                                                  NA
                                                     .TON/HR (WET CAKE)
       CONCENTRATION OF SOLIDS IN CAKE
       PRECOAT (TYPE, QUANTITY, THICKNESS)

       REMARKS 	
4.
        SLUDGE FIXATION

           POINT OF ADDITIVES INJECTION

           FIXATION MATERIAL COMPOSITION

           FIXATION PROCESS  (NAME)
                                                  None
       FIXATION MATERIAL REQUIREMENT/TONS  OF  DRY  SOLIDS  OF  SLUDGE
                         A-ll
                                                   5/17/74

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             ESTIMATED  POND LIFE,  YRS.
             CONCENTRATION OF SOLIDS  IN FIXED SLUDGE

             METHOD  OF  DISPOSAL OF FIXED SLUDGE
             INITIAL  SOLIDIFICATION TIME OF FIXED SLUDGE

      5.   SLUDGE  QUANTITY DATA

             POND/LANDFILL SIZE REQUIREMENTS,  ACRE-FT/YR

             IS POND/LANDFILL ON OR OFFSITE    On-site
             TYPE  OF  LINER                 '	Natural -clay
             IF  OFFSITE,  DISTANCE  AND COST OF TRANSPORT
             POND/LANDFILL DIMENSIONS AREA IN ACRES  45-acre evaporation
                                      DEPTH IN FEET. 	pond

             DISPOSAL PLANS;  SHORT AND LONG TERM    	
N.   COST DATA
     1.   TOTAL INSTALLED CAPITAL COST  	$11,000,000

     2.   ANNUALIZED OPERATING  COST     	.	
                           A-12                    5/17/74

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3.
COST BREAKDOWN
COST ELEMENTS
CAPITAL COSTS
S02 SCRUBBER TRAINS
LIMESTONE MILLING
FACILITIES
SLUDGE TREATMENT &
DISPOSAL POND
SITE IMPROVEMENTS
LAND, ROADS, TRACKS,
SUBSTATION
ENGINEERING COSTS
CONTRACTORS FEE
INTEREST ON CAPITAL
DURING CONSTRUCTION
ANNUALIZED OPERATING COST
FIXED COSTS
INTEREST ON CAPITAL
DEPRECIATION
INSURANCE & TAXES
LABOR COST
INCLUDING OVERHEAD
VARIABLE COSTS
RAW MATERIAL
UTILITIES
MAINTENANCE
INCLUDED IN
ABOVE COST
ESTIMATE
YES NO
ED ED
ED ED
ED a
ID
ED
ED
ED
ED
ED
ED
ED
ED
ED
ED
ED
1
a
ED
ID
a
ED
ED
ED
a
ED
1
a
ESTIMATED AMOUNT
OR % OF TOTAL
INSTALLED CAPITAL
COST
















      A.
      B.
                             A-13
                                                      5/17/74

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     4-  COST  FACTORS




         a.  ELECTRICITY




         b.  WATER




         C.  STEAM (OR FUEL FOR REHEATING)




         d.  FIXATION  COST	
         e.   RAW MATERIAL PURCHASING COST




         f.   LABOR:   SUPERVISOR       	




                      OPERATOR         	




                      OPERATOR HELPER  	




                      MAINTENANCE      	
                               $/TON  OF DRY SLUDGE




                              	 $/TON' OF DRY SLUDGE




                              _ HOURS/WEEK	WAGE
O.   MAJOR PROBLEM AREAS:   (CORROSION,  PLUGGING,  ETC.)




     1.   SO- SCRUBBER,  CIRCULATION TANK AND PUMPS.
          a.
PROBLEM/SOLUTION.
     2.   DEMISTER




               PROBLEM/SOLUTION.
     3.   REHEATER




          PROBLEM/SOLUTION.
                           A-14
                                    5/17/74

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4.   VENTURI SCRUBBER, CIRCULATION TANKS AND  PUMPS




     PROBLEM/SOLUTION	
5.   I.D. BOOSTER FAN AND DUCT WORK




     PROBLEM/SOLUTION	
6.   LIMESTONE MILLING SYSTEM OR  LIME  SLAKING




     PROBLEM/SOLUTION	
7.   SLUDGE TREATMENT AND  DISPOSAL




     PROBLEM/SOLUTION	
                      A-15                     5/17/74

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     8.   MISCELLANEOUS  AREA INCLUDING BYPASS SYSTEM

          PROBLEM/SOLUTION	
P.   DESCRIBE FACTORS  WHICH MAY NOT MAKE THIS A REPRESENTATIVE
     INSTALLATION	
Q.   DESCRIBE METHODS  OF  SCRUBBER CONTROL UNDER FLUCTUATING
     LOAD.   IDENTIFY PROBLEMS WITH THIS METHOD AND SOLUTIONS.
     IDENTIFY METHOD OF pH CONTROL AND LOCATION OF pH PROBES.
                           A-16                    5/17/74

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R.
COMPUTATION OF FGD SYSTEM AVAILABILITY FACTOR
                     BOILER RATING OR MAXIMUM CONTINUOUS CAPACITY, MW
PERIOD
MONTH/YEAR












FLUE GAS DESULFURIZATION MODULES
MODULE A
DOWN DUE TO
BOILER
(HRS)












MODULE
(HRS)












MODULE B
DOWN DUE TO
BOILER
(HRS)












MODULE
(HRS)












MODULE C
DOWN DUE TO
BOILER
(HRS)












MODULE
(HRS)












MODULE D
DOWN DUE TO
BOILER
(HRS)












MODULE
(HRS)












Availability factor computation:  1,
                                Divide boiler capacity by the number of modules
                                and obtain MW/module = x
                                Multiply boiler capacity by number of hours
                                during period = a
                                Add all down times due to module trouble for all modules
                                during period = b
                                Add all down times due to boiler trouble or reduction
                                in electricity demand for all modules during period = c

                                Availability factor = [a ~^_(b + c)]10°  =     %
                                                                           5/17/74

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   APPENDIX B




PLANT PHOTOGRAPHS
     B-l

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Photo No. 1  General view of the Reid Gardner Station
of the Nevada Power Company.
Photo No. 2  Stack plume-scrubber in operation,
                          B-2

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Photo No. 3  Scrubber module and gas outlet duct,
Photo No.. 4  Sludge pond and effluent stream,
                          B-3

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Photo No. 5  Duct after cyclone to I.D. fan.  Note hot-
air duct into scrubber exhaust stream.
                         B-4

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                                TECHNICAL REPORT DATA
                          (Please read Inunctions on the reverse before completing)
 1 REPORT NO
 EPA-6bO/2-75-057-j
                                                      3 RECIPIENT'S ACCESSION NO
 4 TITLE AND SUBTITLE
 Survey of Flue Gas Desulfurization Systems
 Reid Gardner Station, Nevada Power Co.
                                   5 REPORT DATE
                                   October 1975
                                   6 PERFORMING ORGANIZATION CODE
 7 AUTHOR(S)
                                                      8 PERFORMING ORGANIZATION REPORT NO
 Richard W. Gerstle and Gerald A. Isaacs
 9 PERFORMING ORGANIZATION NAME AND ADDRESS
 PEDCo-Environmental Specialists, Inc.
 Suite 13, Atkinson Square
 Cincinnati, Ohio  45246
                                   10 PROGRAM ELEMENT NO
                                   1AB013: ROAP 21ACX-130
                                   11 CONTRACT/GRANT NO.

                                   68-02-1321, Task 6j
 12 SPONSORING AGENCY NAME AND ADDRESS
 EPA, Office of Research and Development
 Industrial Environmental Research Laboratory
 Research Triangle Park, NC 27711
                                   13 TYPE OF REPORT AND PERIOD (
                                   Task Final: 10/74-9/75
                                                                            COVERED
                                     SPONSORING AGENCV CODE
 15 SUPPLEMENTARY NOTES
 16 ABSTRACT
         The report gives results of a survey of flue gas desulfurization (FGD) sys-
 tems to control SO2 and particulate emissions from two existing 125 MW generating
 units at Nevada Power Company's Reid  Gardner Station.  Two additional 125 MW
 units, originally planned for installation in 1976 and 1977, are to incorporate
 similar FGD equipment.  (Installation of the second new unit has been postponed
 indefinitely.)  The FGD systems utilize a sodium carbonate scrubbing process.  The
 systems, placed in operation in April 1974, did not meet SO2  and particulate
 performance guarantees  during their first year of operation.   Each system utilizes
 twin parallel Venturis followed by an absorber tower.  As of August 1, 1975, System
 1 had operated for 3814 hours and System  2, for 2947 hours.  Potential availabilities
 for  the systems seem to  be near 100 percent, but the plant has not had access  to an
 adequate supply of trona, a sodium  carbonate ore  that constitutes the scrubbing
 medium. Alternate sodium carbonate sources were secured recently.
                             KEY WORDS AND DOCUMENT ANALYSIS
                DESCRIPTORS
 Air Pollution
 Flue Gases
 Desulfurization
 Sulfur Dioxide
Scrubbers
Coal
Combustion
Absorbers (Equipment)
 Sodium Carbonates Columns (Process
 Trona                 Engineering)
              	Cost Effectiveness
                                          b IDENTIFIERS/OPEN ENDED TERMS
Air Pollution Control
Stationary Sources
Particulate
Venturi Scrubbers
                                                c  COSATl Held/Group
13B
21B    21D
07A.07D
07B
                                                08G
                                                       14A
 3 DISTRIBUTION STATEMENT
 Unlimited
                                          19 SECURITY CLASS (This Report)
                                           Unclassified
                                                21. NO OF PAGES
                                                    43
                                          20 SECURITY CLASS (Thispage)
                                           Unclassified
                                                                   22 PRICE
EPA Form 2220-1 (9-73)
                    B-5

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