LONG-TERM PERFORMANCE CHARACTERISTICS OF FINE
  PORE CERAMIC DIFFUSERS AT MONROE, WISCONSIN
                         by

            David T. Redmon and Lloyd Ewing
                Ewing Engineering Co.
              Milwaukee, Wisconsin 53209

                        and

                    Henryk Melcer
             Wastewater Technology Centre
              Burlington, Ontario L7R 4AD

                        and

                  Gerald V. Ellefson
                    City of Monroe
               Monroe, Wisconsin  53566
          Cooperative Agreement No. CR812167
                    Project Officer

                  Richard C. Brenner
  Water and Hazardous Waste Treatment Research Division
          Risk Reduction Engineering Laboratory
                Cincinnati, OH 45268
    RISK REDUCTION ENGINEERING LABORATORY
      OFFICE OF RESEARCH AND DEVELOPMENT
     U.S. ENVIRONMENTAL PROTECTION AGENCY
              CINCINNATI, OHIO 45268

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                                     DISCLAIMER
   Development of the information in this report has been funded in part by the U.S.
Environmental Protection Agency under Cooperative Agreement No. CR812167 by the American
Society of Civil Engineers. The report has been subjected to Agency peer and administrative
review and approved for publication as an EPA document.  Mention of trade names :or commercial
products does not constitute endorsement or recommendation for use.

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                                       FOREWORD
                                                                            i

   Today's rapidly developing and changing technologies and industrial products and practices
frequently carry with them the increased generation of materials that, if improperly dealt with,
can threaten both public health and the environment.  The U.S. Environmental Protection Agency
(EPA) is charged by Congress with protecting the Nation's land, air, and water resources. Under a
mandate of national environmental laws, the Agency strives to
formulate and implement actions leading to a compatible balance between human activities and
the ability of natural systems to support and nurture life. These laws direct EPA to perform
research to define our environmental problems, measure the impacts, and search for | solutions.

   The Risk Reduction Engineering Laboratory is responsible for planning, implementing, and
managing research, development, and demonstration programs to provide an authoritative,
defensible engineering basis in support of the policies, programs, and regulations of EPA with
respect to drinking water, wastewater, pesticides, toxic substances, solid and hazardous wastes,
and Superfund-related activities. This publication is one of the products of that research and
provides a vital communication link between the researcher and the user community.

   As part of these activities, an EPA cooperative agreement was awarded to the American Society
of Civil Engineers (ASCE) in 1985 to evaluate the existing data base on fine pore diffused aeration
systems in both clean  and process waters, conduct field studies at a number of municipal
wastewater treatment facilities employing fine pore aeration, and prepare a comprehensive design
manual on the subject. This manual, entitled "Design Manual - Pine Pore Aeration Systems," was
completed in September 1989 and is available through EPA's Center for Environmental Research
Information, Cincinnati, Ohio 45268 (EPA Report No. EPA/625-1-89/023).  The field studies,
carried out as contracts under the ASCE cooperative agreement, were designed to produce reliable
information on the performance and operational requirements of fine pore devices under process
conditions. These studies resulted in  16 separate contractor reports and provided critical input to
the design manual. This report summarizes the results of one of the 16 field studies,


               E. Timothy  Oppelt, Director
               Risk Reduction Engineering Laboratory
                                         in

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                                        PREFACE

                                                              ^            i   •
   In 1985, the U.S. Environmental Protection Agency funded Cooperative Research Agreement
CR812167 with the American Society of Civil Engineers to evaluate the existing data base on fine
pore diffused aeration systems in both clean and process waters, conduct field studies at a number
of nmnicipal wastewater treatment facilities employing fine pore diffused aeration; and prepare a
comprehensive design manual on the subject. This manual, entitled "Design Manual - Fine Pore
Aerafsion Systems," was published in September 1989 (EPA Report No. EPA/725/1-89/023) and is
available from the EPA Center for Environmental Research Information, Cincinnati, OH  45268.

   As part of this project, contracts were awarded under the cooperative research [agreement to
conduct 16 field studies to provide technical input to the Design Manual. Each of these field
studies resulted in a contractor report. In addition to quality assurance/quality control (QA/QC)
data that may be included in these reports, comprehensive QA/QC information is contained in the
Design Manual.  A listing of these reports is presented below.  All of the reports are available from
the National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161
(Telephone: 703-487-4650).                                                  I

1.     "Fine Pore Diffuser System Evaluation for the Green Bay Metropolitan Sewerage
       District" (EPA/600/R-94/093) by J. J.Marx                              !

2.     "Oxygen Transfer Efficiency Surveys at the Jones Island Treatment Plants, 1985-1988"
       (EPA/600/R-94/094) by R. Warriner

3.     "Fine Pore Diffuser Fouling: The Los Angeles Studies" (EPA/600/R-94/095) by M.K.
       Stenstrom and G. Masutani                                          !
     :                            "                          •  .    .         I   . .     •
4.     "Oxygen Transfer Studies at the Madison Metropolitan Sewerage District Facilities"
       (EPA/600/R-94/096) by W.C. Boyle, A. Craven, W. Danley, and M. Rieth

5.     "Long Term Performance Characteristics of Fine Pore Ceramic Diffusers at Monroe,
       Wisconsin" (EPA/600/R-94/097) by D.T. Redmon, L. Ewing, H. Melcer, and G.V.
       Ellefson                                                            !

6.     "Case History of Fine Pore Diffuser Retrofit at Ridgewood, New Jersey"   ;
       (EPA/600/R-94/098) by J.A. Mueller and P.O. Saurer                    ',

7.     "Oxygen Transfer Efficiency Surveys at the South Shore Wastewater Treatment Plant,
       1985-1987" (EPA/600/R-94/099) by R. Warriner                         I

8.     "Fine Pore Diffuser Case History for Frankenmuth, Michigan" (EPA/600/R-94/100) by
       T.A. Allbaugh and S.J. Kang                                         :

9.     "Off-gas Analysis Results and Fine Pore Retrofit Information for Glastonbury,
   -   Connecticut" (EPA/600/R-94/101) by R.G. Gilbert and R.C.  Sullivan        ;
                                           IV

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10.    "Off-Gas Analysis Results and Fine Pore Retrofit Case History for Hartford,
       Connecticut" (EPA/600/R-94/105) by R.G. Gilbert and R.C. Sullivan       !

11.    "The Measurement and Control of Fouling in Fine Pore Diffuser Systems" >
       (EPA/600/R-94/102) by E.L. Barnhart and M. Collins                    j

12.    "Fouling of Fine Pore Diffused Aerators: An Interplant Comparison"      :
       (EPA/600/R-94/103) by C.R. Baillod and K. Hopkins                     i

13.    "Case History Report on Milwaukee Ceramic Plate Aeration Facilities"    \
       (EPA/600/R-94/106) by L.A. Ernest                                   . ;

14.    "Survey and Evaluation of Porous Polyethylene Media Fine Bubble Tube and Disk
       Aerators" (EPA/600/R-94/104) by D.H. Houck                           ]  .

15.    "Investigations into Biofouling Phenomena in Fine Pore Aeration Devices" :
       (EPA/600/R-94/107) by W. Jansen, J.W. Costerton, and H. Melcer         \
                                                                          i   '
16.    "Characterization of Clean and Fouled Perforated Membrane Diffusers"
       (EPA/600/R-94/108) by Ewing Engineering Co.

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                                        ABSTRACT


    A study of the fine pore aeration system at the Monroe, Wisconsin wastewater treatment plant
was conducted to monitor, over a 2-year period, the oxygen transfer efficiency (OTE) and fouling
tendencies of four different effective pore size ceramic discs.  The plant treats a mixture of
municipal and industrial wastes. Major industrial contributions stem from breweries, dairies, and
cheese plants that account for approximately half the organic load to the plant. The .average plant
flow during the study was 2.2. mgd, and the average influent BOD was 400 mg/L.   '

    The plant has three, two-pass aeration tanks, each with two independent aeration grids per
pass. The diffusers for all but two of the 12 grids had a specific permeability of 26 (BKV0 of 6).
The remaining two grids contained diffusers with specific permeabilities of 38 and 50 (BRV0s of 4
and 3, respectively).  Four pilot test headers were installed in the aeration cells.  Each header had
four diffusers with different effective pore sizes equivalent to the  three types in the plant grid
assemblies.                                                                   ;

    Frequent off-gas surveys using floating hoods and Ewing off-gas analyzers were conducted
during the first weeks of operation of newly cleaned and installed diffusers to observe OTE
changes and  fouling tendencies. Subsequently, OTE/fouling surveys were  conducted at 4-month
intervals. Each survey also included the removal of diffusers from the four test headers for
analysis of BRV, DWP, OTE, effective flux rate, nature of foulant, and cleanability. These
analyses were used along  with the full-scale off-gas evaluations  to identify when diffuser cleaning
should be conducted.                           ,

    The range of optimum  effective pore size as measured by BRV ranged from 4 to 7; in.  w.g. This
encompasses most of the common commercial ceramic diffuser products sold in the United States.
Operating parameters and wastewater characteristics such as organic loading appeared to
influence oSOTE more than did diffuser pore size.  Only minor changes in DWP, BRV, and OTE
were observed, indicating fouling at Monroe was not progressive.  ocSOTE  appeared to be
insensitive to fouling. The adverse effects of fouling with  respect to backpressure, OTE, and
maintenance costs were  found to be less than might have  been predicted from the literature.

    The inexpensive cleaning procedures used in the study, involving a combination of high
pressure water spraying with or without liquid acid treatment and/or brushing, followed by
additional spraying, resulted in nearly complete restoration of the diffusers' original >
characteristics.

    The permeability test was not as effective in characterizing diffusers as anticipated. Other,
more specific tests such  as BRV0 and its coefficient of variation should be evaluated and
considered.

    This report was submitted in partial fulfillment of Cooperative Agreement No. CR812167 by
the American Society of Civil Engineers under subcontract to the  Ewing Engineering: Co. under the
partial sponsorship of the U.S. Environmental Protection Agency. The work reported herein was
conducted over the period of 1985-1988.                                         !
                                             VI

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                                TABLE OF CONTENTS
 Foreword .......................... ..............                  :
 Prefa.ce  ....................................... ] ................ * ....... ' '  .
 Abstract ..... ....... . ...... ..........................  ............ .......
 Figures  ............... ......                 .................... .........
                                                                                .
 Acknowledgements ........................................... '.'.'.''• .......... xi

 Introduction .....................................                              .,
 Objectives  ...............................                \ ........ " .......... «
 Description of Facilities  ........................... ...............]... ....... 4
 Experimental Methods .............. ............ .................... ......... 6
       Experimental Design ................. ......................       ........ g
       Offgas Testing ............. , ..................................   ........ g
       Diffuser Evaluations  .................................          .......... g
 Results and Discussion  .......... ......................       ....... : .......... -^
       Performance of New Diffusers ............ . ...........                  .....  12
       Plant Facilities, Operation and Maintenance . . ..... . ..................          21
       Diffuser Fouling - Theoretical Discussion .............. ............. .........  30
       Pilot Diffuser Study ............. _____ . . ......... ..............  .........  37
       Pilot Study - Figure 15 ......... ................ ............... Y. .. ......  41
       Pilot Study - General ...... ..................... ........................  49
       Foulant Analysis ...................................               .......  KA
       Pilot Diffuser Cleanability ........................ .............:... ......  56
       Full-Scale Performance Tests - Sept., 1985, to June, 1986  .............:.........  56
       Tank Draindowns - May, 1986 ......... ........................   .........  gg
       Full-Scale Performance Tests - June, 1986, to Nov., 1987                 .........  75
       OTE Versus Flux Rate ......................... ....... !!!!!.'.'.'!'!!!.".!.'.'!  84
       Tank Draindown and Diffuser Cleanability - June, 1988  ............ ..Y. ........  88
       Cleaning Costs .................. . ...........                   '. ......    94
       Economic Considerations .................................     * '• .........  95

 Conclusions ..................... . ....................              :           nn
References ...............                                     ...... .........  Q0
                               ................... •• ................ ' .........  yy
Appendices
                                                                                101
                                                                                113
                                        vu

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                                      FIGURES


 Number                     "                                       !
  1           Schematic of Treatment Process                             i
  2           Offgas SampHng Plan		'.'.'.'.'.'.'.'.'. '.'.'.'.'.'.'.'.'.'.'.'"l	in
  3           Clean Water Shop Test Layout	  . .^.........  \	15
  4           Clean Water Test Data - Volumetric Transfer Rate       	'     	
                   Versus Volumetric Airrate	     ;            16
  5           Clean Water Test Data -                    	•' ' ';	
                   SOTE Versus Air Flow Rate for Various Perms                       iq
  6           Clean Water Test Data -                           '	i	
                   SOTE Versus BRV	                    I   •         22
  7           Clean Water Test Data -	•	
                   SOTE Versus DWP	                  •   . '  i    •        99
  8           Clean Water Test Data -                  	" "	'     '	
                   SOTE Versus Specific Permeability/BRVn	                       23
  9           Clean Water Tests Data -                      	'	:	•"
                   Specific Permeability/BRVD Versus BRV .		i            23
 1°           Cross Section of Sanitaire Difiuser Assembly and       	;	
                   Typical Grid Layout	                  25
 11           Plan View of Aeration Tank	   	   26
 12          Monroe Aeration Tanks		    	' '  '	'07
 13  •'   '     Monroe Pilot DiSusers	       	  	'	os
 14          Pilot Unit - 4 Lunger	       " "	|	^
 15           14 Perm (9 BRVJ OTE, DWP, BRV -   "	'	r	
                   Cumulative and Quarterly ..                                      ^
 16          26 Perm (6 BRVJ OTE, DWP, BRV -     ••••••••••	,	*s
                   Cumulative and Quarterly .                                      e-i
 17          38 Perm (4 BRVJ OTE, DWP, BRV -	"	'""	
                   Cumulative and Quarterly ...                         ''            co
 18          50 Perm (3 BRVJ OTE, DWP, BRV -     	'	"	'	
                   Cumulative and Quarterly	                         53
 19          Offgas SampHng Plan -  Tank 3 - Sep., 1985	" ",	'  63
 20          Alpha and Alpha-SOTE Versus Tank Position -	I	
                   September 11, 1985	           ;            65
 21          Alpha and Alpha-SOTE Versus Tank Position -	
                   September 19-21, 1985 . .	                    66
 22           Alpha Versus Time	            	  '	
 23           Alpha and Alpha SOTE  Versus Tank Position -   	     !	'
                   Tanks 2 and 3 -  December, 1985	              ;           71
24           Alpha and Alpha SOTE  Versus Tank Position -    	i	'
                   Tanks 2 and 3 - April, 1986  ...                        i           72
25           Alpha SOTE Versus Time - Grids 1, Tanks 1-3   	'|	73
                                       vui

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26          Alpha SOTE Versus Time - Grids 2, Tanks 1-3	 .            80
27          Alpha SOTE Versus Time - Grids 3, Tanks 1-3	'.'.'.'.'."'•	80
28          Alpha SOTE Versus Time - Grids 4, Tanks 1-3	..... ^......... 81
29          Alpha Versus Time - Grids 1, Tanks 1-3	'.'.'.'.'.'. '.......... 82
30          Alpha Versus Time - Grids 2, Tanks 1-3	 '.''. .......  82
31          Alpha Versus Time - Grids 3, Tanks 1-3	.'.'.'.'.'.'.'.'.'.'.'.'.'','.'.'.'.'.     83
32          Alpha Versus Time - Grids 4, Tanks 1-3	'.'.',[	!	83
33          Alpha SOTE Versus Flux Rate - July, 1986	............ ..J..	85
34          Alpha SOTE Versus Flux Rate - May, 1987  	..........}	86
35          Alpha SOTE Versus Flux Rate - November, 1987 .	87
36          OTE, BRV, DWP, Versus Time - 26 Perm (BRVD 6)               '.	91
37          OTE, BRV, DWP, Versus Time - 38 Perm (BRVn 4)  .             ;	92
38          OTE, BRV, DWP, Versus Time - 50 Perm (BRV0 3)  ...           	93
                                      IX

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                                      TABLES
Number                                                              \

 1           Summary of New Diffuser Characterization Data .	j	14
 2           Clean Water SOTE Performance  .	.	16
 3           Idealized Clean Water SOTE Performance	.17
 4           Clean Water Test Data -                                  .  i'	
                   SOTE Ratio of BRV0 Tested/SOTE of BRVa 6		20
 5           Raw Wastewater Characterization	28
 6           Plant Operating Data	L .......... 29
 7           Chronology of Events by Category  . .. . .	.	31-32
 8           Sequential Chronology of Important Events	 .'	 33-36
 9           Summary of Diffuser Characterization - 4.5 mos	42
 10           Summary of Diffuser Characterization - 8 mos	 43
 11           Summary of Diffuser Characterization - 12 mos	 |. .......... 44
 12           Summary of Diffuser Characterization - 16 mos	45
 13           Estimated Average OTE Based on Cumulative		46
 14           Estimated Average OTE Based on 4 mos. Average	'. . . 1	47
 15           Pilot Diffuser Foulant Analysis	55
 16           Full-Scale OTE Data - Tank 3 - Sep. 11, 1985	 57
 17           Full-Scale OTE Data - Tank 3 - Sep. 19-21,  1985	:.	58-59
 18           Sampling Plan Evaluation - Tank 3, Pass 1	......;...	 60
 19           Sampling Plan Evaluation - Tank 3, Pass 2	               61
 20           Plant Data -                                              ;
                   Offgas Testing Days - Sep. 1985 - Apr. 1986	 .	62
 21           Full-Scale OTE Data - Tanks 2 and 3 - Dec., 1985		69
 22           Full-Scale OTE Data - Tanks 2 and 3 - Apr., 1986	 70
 23           Summary of Diffuser Characterization - Tank 3                 i
                   After 168 Days of Operation .	;	73
 24           Summary of Diffuser Characterization - Tank 3                 ;
                   After 260 Days of Operation	 i.	 74
 25           Foulant Analysis - Tanks 2 and 3	      76
26           EDS Results - Non-Volatile Residue	 .		[ [ .......     77
 27           Plant Data -
                   OfFgas Testing Days - Jun. '86 - Nov. '87	78-79
28           Summary of Diffuser Characterization -
                   Tank 1, 24 mos	.... I	89
29           Summary of Diffuser Characterization-
                   Tank 2 & 3, 24 mos	 ...	......:	90

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                        ACKNOWLEDGEMENTS
     The  authors  wish   to    acknowledge  the  advice,  counsel,
•financial support and direction  of   the American Society of Civil
Engineers   (ASCE) Committee   on   Oxygen Transfer,  New York,  New
York, under  Cooperative  Agreement  No.   812167  between U.S.  EPA
and ASCE,  under the  chairmanship  of  William  C. Boyle  and it's
steering  subcommittee,   under   the  chairmanship  of   Hugh  J.
Campbell, Jr. of E.I.  DuPont de Nemours & Co.  The valuable and
indispensable cooperation, assistance  and  advice provided by the
competent  staff of  the  City of  Monroe,  Wisconsin,  Wastewater
Treatment Plant is gratefully acknowledged.

     The  advice and  financial  support  provided fay  Environment
Canada in the  later phases  of the  study added  measurably to the
significance  of   the  results   obtained   and   are  gratefully
acknowledged, as  are the efforts  and support of Jerome  Wren of
Water Pollution  Control  Corporation  in form of advice, counsel
and equipment provided by them.
                                                    I
     Lastly,  the energetic   and essential   participation in  the
project  of  Joseph  Kitzinger   and  Kathleen  Busack  of  Ewing
Engineering Company, which   contributed significantly to findings
and results obtained are  sincerely  appreciated.     |
                            XI

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                           INTRODUCTION
      Ceramic grid  systems are being applied  to aeration basins
in activated sludge treatment plants at an increasing rate due to
their  high energy  efficiency.   At the  present time,  however,
relatively  little is  known about  the effect  of pore  size, as
measured  by  bubble  release  vacuum and  permeability,  on  the
overall costs  associated with the aeration  function, as related
to oxygen transfer and  maintenance considerations.  Earlier work
initiated  and undertaken  by  Ewing Engineering  Company at  the
Milwaukee, Jones Island Plant  (1) suggested that the optimum pore
size, as measured by specific permeability, may be different from
the value  most typically  applied (approximately  2O-3O specific
permeability).  Savings in power and/or maintenance may result if
the optimum values can be defined.

     Ceramic diffusers are  presently applied in a  wide range of
pore sizes.  The optimum choice is believed to be influenced by a
number of factors including  original transfer efficiency, effect
of  fouling on  back pressure  and transfer  efficiency, and  the
amenability to various  maintenance procedures.  Conflicting data
and opinion exists as to the optimum value.

     Work  reported  by  Anderson    (2)  in  195O,  indicates  no
appreciable  difference in  efficiency after  a year  or more  of
service, even with diffusers up to 12O permeability.  The coarser
diffusers showed a slower clogging rate.

     Earlier  studies of  this subject  by various  investigators
including Roe <3>, King (4),  and Beck  <5), were inconclusive and
were  hampered  by  the  masking effect  of  significant  airside
fouling, which  has been  almost totally eliminated  today.  Some
encouragement   in   potential   improvement  in   selection   of
permeabilities was  provided by  the work  of Anderson  <2> which
indicated that the fouling tendency might be reduced with little,
if any,  loss in  original oxygen  transfer efficiency,  by using
media of  greater permeability   (up to  12O  scfm/fta at  2 inches
water gauge) than is in present use today.            ;

      More recent studies  (14)(15)(16)  have yielded the  impression
that  diffuser   fouling  is   an  almost  inevitable  land  costly
consequence of  the use of  porous fine pore diffusers.

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 ,,„,-•  Rflajively  recent improvements  in oxygen  transfer testing
 under field  conditions and  the development of  more descriptive
 and meaningful tests  to appraise the degree  and consequences of
 fouling <6><7>,  suggested that reinvestigation of  the  effect of
 permeability  may  provide  a  fruitful  and  rewarding  area   for
 investigation.                               .        -

    In  the spring  of  1985,  the  U.S.   Environmental  Protection
 flgency  in  conjunction  with   the  American  Society  of  Civil
 ler'i??™5   in|;tiated  a *°ur-year  study of   fine pore   diffused
 aeration  systems at  a number  of sites throughout  the U.S.  in
 order  to   develop  an  in-depth database   on  their  ^performance
 characteristics.    One of   these  sites,  Monroe,  Wisconsin,   was
 chosen   to  examine  the  effect  of  pore   size as  measured   by
 permeability,   or  bubble   release vacuum,   on oxygen   transfer-
capabilities,   diffuser    fouling  tendencies  and  consequences
 thereof,   and   amenability to   cleaning.    The   basis   for   the
selection  of the   Monroe plant for  this study  was partially upon
the   belief  that   the strength  of  the waste  and loading  would
represent  an aggressive  fouling  environment,  suitable for a studv
of this  type.                                         i          7

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                         OBJECTIVES
The objectives o-f this study are listed below:
                                                    !
         i. Monitor  OTE and  -fouling tendencies  of; four
            different permeability range ceramic discs to
            be installed at Monroe, Wisconsin, over about
            a two—year period.                      \

         2. Identify  maintenance  requirements  of , each
            permeability  type   diffuser  in   terms  of
            relative   cleaning   frequencies   and ;  the
            effectiveness  of a  combination  of in | situ
            high  pressure  water spraying  and  chemical
            treatment  on diffusers  in drained  aeration
            tanks.                                  !

         3. Jo  identify  within   practical  limits  the
            optimum range  of ceramic diffuser  pore size
            at  this plant  based  upon efficiency,  back
            pressure, and maintenance facility and cost.

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                       DESCRIPTION OF FACILITIES
      Monroe,   Wisconsin, is  a community  of  about  1O,OOO people
 located in south-central Wisconsin.    The Monroe activated sludge
 wastewater treatment  plant, located in  the  heart of Wisconsin 's
 dairyland, treats  a mixture of  municipal  and industrial wastes.
 Major  industry includes  Huber  Brewery   and  Bottling;  Frito-Lay
 corn chip production? Roy's  Dairies, primarily related to butter
 production; Oairyland  Specialty Incorporated,  dealing  with whey
 processing;   approximately ten   cheese  plants;  and  a linen  and
 laundry service.   Tnese industries  account for   roughly half the
 organic load  to the plant.                             j   '    -

      During the study,  the flow to  the   treatment plant averaged
 about 2.2 mgd with a minimum of  about  1.5 mgd  and  a maximum of
 about 4.0 mgd.  Influent BOD's varied from about 16O  mg/1 to 80O
 mg/1.,  with an  average of  about 40O mg/1.   Influent;  suspended
 solids ran about 230 mg/1.    Soluble BOD's at Monroe  are higher
 than  typically  encountered in most   municipal plants due  to the
 nature of the industrial   contribution  to the   system.   Influent
 pH's  can and  do vary, from as low as 2.O to  as  high as 12.   This
 is  purportedly  due to  industrial   wash  down  procedures  which
 utilize acidic and caustic  reagents.  The equalization pond aids
 in reducing the variation  of wastewater  pH and organic>loading to
 the secondary process.                                  ;

      From the on-set of  the  study in  September,  1985,  until  June,
 1986,   construction  was  underway  to expand  and  up4grade  the
 wastewater treatment plant.    As part of this  expansion,  one new
 two-pass aeration tank was being  added  to the two existing  tanks
 of  the  same configuation.    The  aeration  tanks include  three
 two-pass tanks, and each pass is 25 ft. wide by  1O2 ft.   long,  by
 15 ft.  side  water  depth.  The opening between passes  jis  about  3
 feet   square.   All   three  tanks are  suited  with the  Sanitaire
 fine-pore   ceramic  grid    system.    Each   pass   contains    45O
 substantially  planer ceramic  disc   diffusers   each  having   a
 projected area  of  about O.41  sq.   ft. On this basis,   there are
 approximately 13.8  sq.   ft.  of  tank bottom per  each  square  foot
 of diffuser area.                                       ;

     Figure  1 represents  a  schematic  of the  treatment  process
 which  includes  coarse screening   and comminution,  grijd removal,
primary  clarification,  equalization   (in-line  or side1  stream),
 aeration, secondary clarification,  sand filtration, chlorination
and post aeration by  cascade aeration.

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                       FIGURE    1


                   MONROE, WISCONSIN


                 SCHEMATIC OF TREATMENT FROCKS
                    RAW WASTE

                        I
              BAR SCREEN & COMMINUTOR

               AERATED GRID REMOVAL
                                PRIMARY CLARIFICATION

                               (2-60 FT" DIAM CURIFIERS)
                                    EQUALIZATION
                                       POND
                (IN-LINE OR SIDE)
SECONDARY CLARIFICATION
 (4QFT,53FT470FT
   DIAW CURIFIERS)
                                    (3-2 PASS TANKS;
                               EACH PASS 25'x 1Q2'x 15'SWD;
                                   TWO GRIDS PER PASS:
                               450 SANITAIRE DISCS PER
  SAND
FILTRATION
CHLORINATION
                                            POST AERATION

                                                 *
                                              DISCHARGE

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                       EXPERIMENTAL METHODS
Experimental Design
     Except as  otherwise noted, all tests   in  this
were conducted in accordance with the ASCE—FBDA Qual
Program Plan (QUAPP).
investigation
ity Assurance
     The primary  dependent variable selected  for   this  study  was
the effective pore size of the ceramic diffusers used.   Pore size
has  historically  been  specified  indirectly on   the   basis   of
permeability, which is determined by  sealing  the  ceramic  unit in
a test fixture substantially as it is in an actual  aeration  tank,
and then passing sufficient air through the dry unit;to  produce a
pressure   differential  of   2.O   inches   water   gauge.     The
permeability is reported as the  air rate, in  standard cubic feet
per minute, to produce this differential.

     Originally, the  test was applied  to diffuser plates  12" x
12" x  1", and  where so  applied, it  provided a   rough indirect
measure  of  apparent  pore  size.  With  the   advent of  porous
diffusers having  different dimensions and shapes,   -the  test lost
its significance as a meaningful  measure of pore  size.  Attempts
to restore  this capability led  to the development of   a  related
characteristic which  is called  specific permeability.  It  is a
value calculated from the results  of a similar permeability test
performed  upon the  diffuser of  interest.  Through[ the  use   of
various  assumptions   regarding  dimensions,   shape,    and  flow
resistance,   calculations   are   performed   to    estimate    the
permeability that  would be  obtained in a  diffuser!of  the same
material and  uniformity in a  square plate configuration,   12" x
12" x 1"  thick.  Assumptions applied in this  study !are that  air
flux is directly proportional to area normal to flow!and pressure
gradient in the direction of flow in consistent units.

     Permeability  was  initially  selected  as the descriptive
parameter for this study because in the past it had been employed
as the usual method of differentiation with respect to pore  size.
It   is  considered   appropriate  to   delineate   some    of   the
shortcomings  of  this  parameter   in  the  characterization   of
diffuser media.
     1.)    The  method of  its  measurement  is not  specifically
           defined in any generally accepted reference.

     2. )    There is no known  method of accounting fpr dimensions
           or  shape  to  establish equivalence  to—+the  article
           implicit  in its  definition  which  is 12  x  12 x   1
           inches.                                    i

-------
      3. )    There   are   no  known   procedures  to   account  -for
            variations in temperature, pressure or humidity.

      4.)    There  is no known  procedure to account for variations
            in  uniformity  that may exist.   Thus, differentiation
            is  not possible between  a nan—uniform unit, which may
            pass most of the air through a limited area with large
            pores,  and   a  unit  with  uniform   though  smaller
            effective pore size.                      |
                                                      i
            However,  in  reasonably uniform  diffuserslof  a given
            geometric  shape, a  reasonably good  correlation does
            exist   between  the  new or  original  bubble  release
            vacuum     and  the  specific  permeability  
-------
     The  approach  used   in   the work  was  to initially  conduct
frequent offgas  surveys   to  observe OTE changes  within the first
few weeks  of operation   and intensive  monitoring of  fouling of
each permeability type using removable pilot equipment, each with
four diffusers   suspended over  the full-scale  test gfids.   After
the initial  intensive work, the combination  OTE/fouling surveys
were reduced to  approximately 4 month intervals.
                                                      i
     Individual  diffusers were  periodically removed from the four
pilot headers,   each having  a different  permeability grouping of
diff users for  analysis  of  BRV, DWP versus  air flow  rate, OTE,
effective  flux  ratio,   <7>  nature  of foulant  and cleanability.
The information  from these analyses  was used in combination with
the  full-scale  offgas   evaluations to  identify  when  diffuser
cleaning should  be  conducted.                         !
                                                      !
     In addition to full-scale  process water testing, a series of
clean water  shop tests   (ASCE  Standard  - Measurement  of  Oxygen
Transfer in Clean   Water)  on each permeability  type diffuser was
conducted  at  the  aeration supplier's facility  for  the  same
placement and  water depth of   the full-scale tanks,  j  Except for
the  26  specific permeability   
-------
     To   increase  the  productivity,   multiple off gas j  collection
hoods Mere  built and used.   Eight collection hoods, 4:-ft.  wide by
8 ft.  long,  were constructed using   half-inch plywood,  2  x 2's
and  I x  lO's.   The plywood  was used  for the top and the 1 x lO's
formed the  vertical  sides.   Styrofoam, 2 in.  thick, iJjas attached
to the   inside  surfaces  to provide  stability, buoyaricy,   and to
reduce   the volume  of  gas  within   the  hood,  decreasing  its
residence time.                                       !

     The offgas was  drawn  by vacuum  through a  1.5 inch  diameter
flexible crushproof  hose.   A pressure  tap was located! on the 1.5
inch diameter discharge  fitting  from the hood.  A  1/4 inch I.D.
by 3/8 inch O.D. polyethylene tube was used to transmit  the hood
pressure to the offgas analyser,  where the operator could  observe
the pressure  or vacuum inside tha hood, and thereby1  adjust the
rate of  offgas withdrawn to match the flux rate at that position.
Typically vf?r y  stable flux rate  measurements  were obtained with
hood pressures of  about +. O.2 inch water gauge.      ',
                                                      i
     The sampling   positions used during  the study are  shown in
Figure   2.   Early  in  the offgas testing  program :a  rigorous
sampling of  one   of   the    aeration  tanks  was  conducted.    A
mathematical  analysis of   the data  indicated  a less  extensive
sampling plan  could be employed.   This plan,  which jsampled two
locations (the  A  and  C  positions) on eight cross-sections  of a
basin, was  typically used throughout  the study.      j
                                                      !

Diffuser Evaluations       .                          '

     The diffusers employed  in the study were  provided by Water
Pollution  Control   Corporation  (BanitaireR).    They  were  disc
diffusers,  approximatley   9  in.   diameter by  3/4  in.    thick,
mounted   in a  PVC holder   with  two*O.17O  in. diameter   control
orifices as shown   in  Figure 1O.   The diffuser seals  are  3/8 in.
cord  diameter  O-rings of  polyisoprene  with  hardness   of   4O
durometer Shore A.   The compound  conformed to the requirements of
ASTM  D—1869.   The  pipe and  holders  are extended land   molded
respectively  from   PVC stress    rated  compound   meeting  the
requirements of  cell  classification   124524 of ASTM |D-3915.   In
addition, the  pipe  itself  conforms  to the requirements   of ASTM
D—3O34   and  has   the   additional   requirement   of  2.7.  TiO-z  for
improvement of its resistance to  ultraviolet radiation.
                                                      i
     The diffusers  themselves  were composed   of  alumina  grit
graded    in  standard    foundry   grade  sizes   and molded   at
approximately  1,5OO  psi.    Separate standard   grit sizes  were
selected  for   each  of   the different   BRV0  classifications
furnished.   Blending  of the grades   to obtain  the desired  BRV
classifications    was   not    practiced.    The    diffuser   banding
material, a  high  alumina glass  composed largely of clay,  flint

-------
              FIGURE   2
        mm, WISCONSIN
           OFFGAS SAMPLING PUN
TANK 3
TANK 2
TANK1





4'x8'
OFFGAS
HOODS





J4
CIBIA
4
GRID 3.2
3.3
CIBIJ
3.2
CIBN
GRID 3.1
4
3.1
CIBN
t
1
RAS
•

15
AIBIC
GRID 3.3
3.6
AIBIC
3.7
AIBIC
GRID 3.4
3.8
AIBIC

i '


/5
CIBIA
GRID 2.3
16
CIBIA
2.7
CIBIA
GRID 14
18
CIBIA


«i —
1

AlfilC
4,
GRID 2.;
13
AIBIC
12
AIBIC
GRID 2.1
4
11
AIBIC
t
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RAS


^
C 1 1 1 A
;RID 1.2
1.3
1IBIA
1.2
:IBIA
;RID LI
1.1
:IBIA
t
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1
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kit 1C
GRID 1.3
1.6
AIBIC
1.7
AIBIC
GRID 1.4
1.8
AIBIC

1 '
«r1
                                         4'x 8'
                                      OFFGAS HOODS
                                      TO
                           CURIFIER
                                       INFLUENT
              10

-------
and -feldspar,  was added in a  ratio of approximately 1:5  to the
grit and -fired at approximately 2,4OOC>F.              '

     The ceramic diffuser characterization tests were conducted a
number of-times during the investigation to:          i

     —     Define  the initial  characteristics of  the diffusers
           used in the study                          ,

     -     Quantify  changes  in   the  diffuser  characteristics
           caused by fouling and

     -     Evaluate the  effectiveness of a  restorative cleaning
           procedure

     The  diffusers were  characterized by  dynamic wet  pressure
(DWP),  bubble release  vacuum  (BRV), flow  profile measured  by
effective  flux ratio  (EFR)  and  foulant analysis.   Full-scale
clean water oxygen transfer tests were conducted according to the
ASCE  Oxygen  Transfer  Standard  (9) ,   for  each  of  the  four
permeability types  included in the study,  at the manufacturer's
shop  test facility.   Original characteristics  are reported  as
Tables 1 and 3.

     In  addition,  clean   water  steady-state  oxygen  transfer
efficiency (OTE) tests were conducted on new and fouled diffusers
to evaluate quantitatively changes in OTE due to diffuser fouling
and  subsequent changes  resulting from  diffuser cleaning.   The
steady-state  tests were  run  in  the laboratory  in ! a 30  inch
diameter  column with  10 feet  of diffuser  submergence.  Steady
state  conditions  were  established by  continuously  pumping  a
concentrated sodium sulfite solution into  the tank tq maintain a
dissolved oxygen  concentration of 1.0  to 3.O mg/1.   The oxygen
transfer  efficiency   was  measured  by  offgas   analysis  once
equilibrium  conditions  were   established  (6)(11).  '  The  test
utilizes  two  diffusers with  independent  air  feed lines,  and
typically compares  the OTE  of a fouled  diffuser against  a new
diffuser element  of the same  manufacture, in the  same geometry
and air flow  rate.  By switching the air flow  from one diffuser
to  the other,  an accurate  appraisal of  the difference  in DTE
between the two units can be quickly obtained (6)(10)(11).
                              11

-------
                      RESULTS AND DISCUSSION
Performance of Max Pi-ffusers                          ;

     Prior to  installation of  the ceramic di-ffusers  onto pilot
headers or full-scale grids, several  diffusers of each type were
sampled  and tested  to  establish the  initial properties.   The
DWP's, BRV's, air flow profiles and permeabilities are summarized

in Table 1.  It  is apparent that an ample range  of BRV, DWP and
permeability  of  the  four   types  of  ceramic  diffusers  were
obtained.    The discs  were carefully  measured so  that reliable
estimates of specific  permeability and BRV0 could  be!made.  The
group incl-uded  diff users of nominal  BRV0 9 inches, 6  inches, 4
inches and 3 inches water gauge.                      :

     Thirty—six diffusers from each permeability group;were clean
water  tested  at  the  design   water  depth  of  14.3  ft.  and
submergence of  13.5 ft.   The 26 specific  permeability diffusers
were shop tested at 1.2 scfm  per diffuser, while the others were
tested  at 0.5,  1.0 and  2.0 scfm  per diffuser.   As previously
indicated, three replicate tests were  run at each air Irate.  The
tests were run in accordance  with the ASCE Standard (9).  Except
for the 26 specific permeability diffusers, the test sequence was
randomized  with respect  to  air  flow rate,  such  that no  two
consecutive  tests  were conducted  at  the  same air  flow.   In
addition,  water samples were taken after each test for;subsequent
tot ail dissolved solids (TDS) determination.
                                                      i
     Figure 3  is a  plan view  of the  Sanitaire shopi  test tank
which  was used,  including  the diffuser  layout employed.   The
results of the clean water tests are presented in Tables 2, 3 and
4 and Figures 4 and 5.                                :

     Table 2 is a summary of the actual clean water test results,
corrected to  a 10OO rag/I  TDS concentration, using  an empirical
correction procedure  similar to that described  by Benedek (12),
for each set of replicate tests conducted.  Figure 4 is a plot of
standard volumetric transfer rate  versus volumetric air rate and
air flow  per diffuser  developed from Table  2 data. :  Each line
represents  the average  transfer rate  characteristics for  each
permeability  tested.   Table 3  idealized  SOTE  data;were  back
calculated from Figure 4 for O.5, l.O and 2.O scfm per diffuser.
                               12

-------
     Figure 5 shows the relationship  o-f  SOTE versus air flow rate
per diffuser.   The smoothed  curves  were  generated  by computf™
SOTE from the transfer rate data in Figure 4.   These data sugges?
inaLuS7 littlS  di«erence *" SOTE  or  SOTR exists  over Tranje
in BRV from approximately 4-9 in.   wg., however,  at a BRV of 2?7

ctarlinl",?«;!?-  3> *hBre  iS aPParer*ly  a  significant incremental
decline in clean water performance, relative to the other types.

     Table 4 presents  the SOTE of each permeability  tested as a
1^10  ~     diffusers having a specific permeability of  26 (BRV0
6 ).   Ceramic dome  and disc  systems supplied in the  U.S.  are
rountinely supplied having  equivalent specific permeabilities in
the range of 2O  to 3O; this is the basis   for  comparing  the SOTE
of  the  various  permeabilities   to  those  having   a'  specific
permeability of 26.                                       *»H*«-*TIC
                               13

-------
                             TABLE 1
MONROE, WISCONSIN
!
SUMMARY
SERIES
CONDITION
1
OF NEW DIFFUSER CHARACTERIZATION DATA
1
i
K35-65
NEW
AVB. ERV0 (in. wg. > 8.77
BRVo NOMINAL
s/x
AIRRATE
@ O.5O cfm
@ 0.75 cfm
© 2.OO cfm
@ 3.10 cfm
DWP
@ O.75 cfm/BRV
AIR: FLOW PROFILE
FLUX RATE CENTER
FLUX RATE MIDDLE
FLUX RATE OUTER
PERMEABILITY
SPECIFIC
PERMEABILITY* *»
9
0.032

7.O1
7.49
8.98
10.44
O.S54
{scfm/sq. ft.)
O.67
1.51
2. 19
8.4
14.3
K35-66
NEW
5.77
6
O.O36
DWP   assumes flow resistance proportional to flow path
       length, resistance per unit length is proportional
       to flux rate, flow area is 144 in= in reference
       diffuser and 59 in3 in diffusers employed.
                              14

-------
   AREA TANK
m DIFFUSERS
= 13.9
                  34M"
                                      FIGURE   3
                               CLEAN fAe SHOP JEST 1AM
                                         FOR
                                   HE, WISCONSIN





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                                               6'-0"
                                                                   SHOP JEST
                                                                     IANK
                                           15

-------
                                TABLE
                              MONROE,  WISCONSIN
                    CLEAN  HATER  OXYGEN  TRANSFER  RESULTS
 DIFFUSER

 BRV0 = 9
 SP. PERM  14
 BRVo  =  6
 SP. PERM   26
 BRVo =  4
 SP. PERM  38
BRV0 = 3
SP. PERM  50

AIRRATE
(ccf*>
17.81
17.91
18.14
35.83
35.94
36.18
43.06
71.80
71.84
72.38
44.00
43.60
43.50
18.00
18.02
18.04
36.00
36.08
36.18
71.94
71.95
72.02
17.93
18.00
18.01
35.97
36.12
36.23
71.68
71.82
72.13

t
36
VOLUMETRIC
AIRRATE
(scfs/1000 ft3)
6.046
6.080
6.159
12.164
12.202
12.283
14.619
24.376
24.390
24.573
14.938
14.802
14.768
6.111
6.118
6.125
12.222
12.249
12.283
24.424
24.427
24.451
6.087
6.111
6.114
12.212
12.263
12.300
24.335
24.383
24.488
AREA TANK
IREA DIFFUSER
OIFFUSERS TESTED

SOTE

31.49
31.42
32.66
28.11
27.01
29.08
28.75
25.69
26.19
25.37
27.94
27.63
27.58
29.78
29.92
33,23
29.60
27.87
27.27
25.71
24.84
24.19
30.98
30.08
27.01
27.60
25.93
26.54
24.47
24.19
23.53



   VOLUMETRIC
    TRANSFER
(lbs/day/1000 ft3)

      47.58
      47.74
      50.26
      85.45
      82.36
      89.26
     105.03
     156.49
     159.63
     155.79
                                                             104.30
                                                             102.21
                                                             101.7.9
                                                              45.48
                                                              45.74
                                                              50.86
                                                              90.41
                                                              85.31
                                                              83.71
                                                             156.92
                                                             151.63
                                                             147.81
                                                             47.13
                                                             45.94
                                                             41.27
                                                             84.23
                                                             79.46
                                                             81.58
                                                            148.81
                                                            147.40
                                                            143.99
     C0NCENTRTnMnftn«        T° A TOTftL '"SOLVED SOU 108   MEASURED SOTE x  t
           Where:
                       LOS  i   =   (1000  -  TDSM.l  x  10~s
                                      16

-------
                       TABLE  3
                  MONROE, WISCONSIN
        IDEALIZED CLEAN WATER SOTE PERFORMANCE
BRVo
.
,
AIRRATE
PER UNIT
(scfm)
0.5
1.0
2.O

9"
.
14
SP. PERM

31.6
28.1
25.7
'
6"
"
26
SP. PERM

31.3
27.7
25.2
s
> 4"
3S
SP. PERM

3O.9
27.4
24.9
.
'
3"
5O
SP. PERM

29.6
26.4
24. 0
•
THESE VALUES WERE OBTAINED FROM FIGURE 5 SMOOTH;CURVES
                        17

-------
                  FIGURE   4

   MONROE,  WISCONSIN  CLEAN WATER TEST DATA

   VOLUMETRIC TRANSFER RATE VS VOLUMETRIC  AIRRATE
220
200
180
160
140
120
100
80
60
40
20
0


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2.5
                      18

-------
19'

-------
                            TABLE  4                 ;
                                                    - I




                       MONROE, WISCONSIN             !
                                                     I






             RELATIVE CLEAN WATER SOTE PERFORMANCE



         RATIO SOTE OF BRV0 IN QUESTION/SOTE of BRV0 6
BRV0
AIRRATE
PER UNIT
(sc-f m)
O.5
l.O
2.O
X
9"
f
14
SP. PERM
1.O1O
1.014
1.O2O
1.O15
6"
26
SP. PERM
l.OOO
1.000
1 . OOO
1 . 000
'
4"
38
SP. PERM
O.987
O.989
O.9S8
.
O.9SS
13"
! 5O
SP. PERM
I
1
0.946
i
0.953
O.952
1
0. 950
THE ABOVE RATIOS WERE OBTAINED FROM TABLE 3 IDEALIZED OTE VALUES
                             20

-------
     The   relationships    between    BRV,    DWP,    and   specific
permeability versus, the relative ratio  of  clean water  SOTE are
presented  in  Figures  6,   7   and  8.    Figure  9  indicates  the
relationship between  BRVQ  and  specific  permeability. ''   Since BRV
and DWP at about 2 scfm/sq.ft.  are  similar in magnitude for clean
diffusers and are an indirect   measure of  effective pore size, it
is not  surprising that a similar   trend between  DWP and  BRV and
relative DTE exists.   In both  cases, as the  effective pore size
increases with increasing permeability,  the OTE  and the pressure
to produce bubbles (as measured by  DWP and BRV) decrease.

     The relationship between permeability and BRV is of interest
both from  a specification   and quality  control   viewpoint.   Many
specifications require  permeability  tests to be   conducted in an
effort  to  control  uniformity,  effective  pore   size  and  back
pressure of the diffuser elements to  be  installed in the aeration
system.  Although  there is no  recognized  standard procedure for
measuring permeability,  the test   specified usually  involve the
measurement of air flow through the  dry diffuser at an operating
pressure  of 2  in.  w.g.    The air  flow  rates  involved in  the
permeability test are  many times that of  an operating diffuser,
as is the differential pressure across  the  diffuser.|  The reason
for  this discrepancy  is   that the  permeability  test does  not
include the important effect of surface  tension which'constitutes
a large fraction of  the back pressure of  an operating diffuser.
This  deficiency is  further complicated  by a recent advent  of
diffusers of  a variety of   geometric shapes,  which preclude the
comparison of the desired characteristics  through the:application
of this test.   Procedures  for  relating  the  results of this test
on diffusers of differing geometric shape  are not reliably known.
Furthermore, since  the test measures only  an overall  resistance
to Flow it gives no indication  of uniformity within arj individual
dif-Fuser under test.

     On the other  hand, the BRV test which  is conducted  at flux
rates  and pressure  differences comparable   to service  and does
include  the effect  of surface tension,  is  not subject   to the
deficiencies   of   the   permeability   test  outlined   above.
Additionally,  the  coefficient  of  variation of   multiple  BRV
determinations on a single  diffuser does provide  a useful  measure
of uniformity of  individual diffusers.  It  is for these  reasons
that the BRV , test is considered to be a  far more applicable and
meaningful  test  than the  permeability  test and is  therefore
employed in  this work as   the  principal gauge of  effective pore
size.


Plant Facilities. Operation and Maintenance

     As indicated earlier,  the  Monroe plant  was in  the midst of a
plant  expansion  at  the  time  the  aeration   study  began  in
                               21

-------
 5


 "o
 o
 I
                                  FIGURE
                             MONROE. WISCONSIN
1.04
1.03 -
1.02 -
1.01 -
1.00 -
0.99 -
0.88 -
O.S7 -
0.88 -
0.95 -
0,94 -
0.93 -
0.92 -
0.91 -
0.90 -
0.89 -
0.88 -

















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14
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                                FIGURE   7

                            MONROE, WISCONSIN
1.04
1.03 -
1.O2 -
1.01 -
1.00 -
0.99 -
0.98 -
0.97 -
0.96 -
0.95 -
0.94 -
0.93 -
0.92 -
0.91 -
0.90 -
0.89 -
0.88 -












































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12
       14
                                22

-------



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~
5
Id
§
I
u
a



t.04
1.03
1.02

1.01
1.00
O.M
0.98

0.97
0.98
0.93
0.94
0.93
0.92
0.91
0.90
0.89 •
0.88 -
                                       FIGURE    8

                                  MONROE, WISCONSIN

                               SP. PERM/BRV(0) VERSUS RELATIVE SOTE
                      10
                                        5
                                 SPECIFJC PERMEABIUTYXBRV(0)2'7
                                  60   SPECIFIC PERKABILITY
                                         BRV(O)   .
*"•»
  MONROE, WISCONSIN

JUV VERSUS SPECIFIC PERMEABILITY
                                                                      14
                                    23

-------
 September,  1985.   At that time  a new third aeration tank similar
 to the two  existing tanks was  brought on line.  The new two—pass
 tank  was the first ceramic grid system in operation at the plant.
 Subsequent   construction involved  draining  the existing  tanks,
 removing the old  Chicago  Pump coarse bubble Disc-fuser diffusers
 and retrofitting  the  basins with fine pore  ceramics!  Figure 1O
 shows  both  a cross-sectional  view  of  the Sanitaire  diffuser
 assembly and  a perspective  drawing illustrating a  typical  disc
 grid  layout.                                          ;•

      The retrofit of Tank 2  was completed in mid-November, 1985.
 DUE? to construction  delays, Tank 1 was not  completed until  May,
 19S6.   As a result, from September, 1985, to June,  1986,  only two
 of  the  three aeration  basins were  in operation;   however,  from
 that  time on  all  three basins were in service.        :

      Figure  11  is  a  plan  view of  a  typical  aeration  tank
 indicating  the basin geometry and the disposition of the  aeration
 equipment.    Figure  12  indicates   the  grid  nomenclature   and
 specific permeability of  the diffusers  installed therein,   the
 location of the  five pilot diffuser headers and the flow scheme
 employed during the  study.   Return sludge was  introduced to the
 inlet   of  the first  pass,   while  wastewater from  the   primary
 clarifiers  or the equalization basin was fed from three locations
 within the   first pass.    Typically, the  return sludge  flow was
 held at   7O-8O% of   the waste  flow which  was split  between the
 three    addition   points   at  roughly   4O-4O-2OX   respectively,
 proceeding  in the direction  of flow.                  :

     Table  5  presents the monthly wastewater characteristics  from
 start  up  in  September,   1985,  through  June,   1988.    Table 6
 presents information   on  a  selected  number  of ioperational
 parameters  over the same period.                      :

     During this  period  of  time,  the aeration tanks were  operated
 as  three parallel   two-pass  basins.   On  several  occasions   the
 equalization  pond,  which was used in-line,  was  brought  on  line or
 removed  from  service as noted in   Table 6.   In  addition,  Tables 7
 and 8  provide chronologies of  important events  by catagory and as
 they occurred in  sequence, respectively.              :

     Due  to   the  staggered start   up  of the aeration basins,  the
 fine pore diffusers  in  Tanks 2 and 3 which  had operated  for  168
days and  26O days   respectively,  were field cleaned  in   situ in
mid-May,  1986.   The cleaning  procedure   involved hosing   the
diffusers off  with  effluent,   applying diluted muriati£ acid with
a commercial  weed sprayer,   hand  brushing with  a stiff brush  and
rehosing.  A  couple of diffusers  that  were  removed  from each grid
prior  to cleaning,   were quickly  conveyed to   Ewing Engineering
Company in Milwaukee for careful  evaluation.
                               24

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                                          FIGURE   1O
RETAINER
  DIFFUSER HOLDER
   AIR DISTRIBUTOR PIPE
            CURRENT
       CONFIGURATION
                                                      Aluminum Omdi Diie
                                                             O-Rmg \ Comour«d Surfaci
                                                               _f   \	\
                                                 ComprtiMd ESjt

                                                      Control OrKict
                                                                                 <-in,PVCPip«
                                                                       SANITAIRE
                                                                  1985 CONFIGURATION
                     Tjplcoa Ceramic Disc Grid Layout
                                              25

-------
UJ
QC


g

u.
1
(I
1
II
1!
«
I
i
i
n
i!
n
i
i
i
i
!
S
li


i
I
I
j
1

1
ii
i!
iii
i

1
l!i
1
i

li
ii
1
i!
i
i
i
i

S
!!
1
i

1
Iii
;
h
8

I
li
                                       It
I
2
                                                                                                         u
                                                                                                         l/l
                                                                                                         s
                                                                                                         g
                                                     26

-------
                FIGURE   12
           MONROE, WISCONSIN
                AERATION TANKS
TANK 3
TANK 2
TANK1
1
r~
26
SPERM
<
i
GRID 3.2

^
26
SPERM

GRID 3.1
t
1
RAS
i

I
26
SPERM

GRID 3.3


26
SPERM

GRID 3.4


^
26
S PERM

GRID 2.3


26
SPERM

GRID 2.4

	 . — _
i
T 26
SPERM
I 1
GRID 2.2
*
PILOT
UNITS
i 38
TS PERM
1
GRID 2.1
t

-------

MONTH/YEAR

= ====s: ==r==s=s=2
Sapte«bar, 1985
October, 1985
Noveaber, 1985
December, 1985
January, 1986
February, 1986
March, 1986
April, 1986
May, 1986
June, 1986
July, 1986.
August j 1986
September, 1986
October, 1986
November, 1986
DacBDbar, 1986
January, 1987
February, 1987
March, 1987
April, 1987
May, 1987
June, 1987
July, 1987
August, 1987
September, .1987
October, 1987
Novsiber, 1987
Decaabar, 1987
January, 1988
February, 1988
March, 1988
April, 1988
May, 1988
June, 1988
INFLUENT
FLOW
(M.S.D.)
==========
1.80
1.93
2.29
2.04
1.84
1.95
2.38
2.05
2.23
2.17
2.14
2.15
2.59
2.52
2.11
2.03
1.98
1.85
1.95
2.11
2.28
2.35
2.18
2.44
2.23
2.23
2.03
2.03
2.06
2.04
1.94
1.99
1.93
1.99
                        TABLE  5


     WASTEWATER CHARACTERISTICS - MONROE, WISCONSIN

              Septetbar, 1985 - June, 1988
              RAN       RAH
              BOD3   SUSP.  SOLIDS
             CONCEN.    CONCEN.
                  (M6/L)
               369
               347
               336
               463

               494
               484
               397
               401
               415
            '   434
               483
               392
              397
              360
              370
              386

              386
              415
              399
              351
              410
              434
              412
              477
              410
              461
              418
              431

              389
              419
              375
              369
             449
             551
  198
  176
  197
  240

  237
  218
  201
  211
  202
  231
  239
  217
 286
 237
 253
 227

 216
 288
 227
 204
 220
 252
 245
 246
 230
 257
 243
 277

 234
 225
215
201
203
241


FLOW TO
AERATION
(M.6.D.)

BOD=
CONCEN.
TO AERATION
(MS/L)
=======================
1.80
1.93
2.29
2.04
1.83
1.56
2.48
2.16
2.32
3.04
2.46
2.37
2.86
2.81
2.35
2.27
2.19
2.12
2.17
2.36
2.52
2.61
2.61
2.76
2.60
2.50
2.39
2.35
2.40
2.35
2.23
2.28
2.17
2.30
207
223
259
349
355
339
251
257
232
300
350
289
276
245
260 *
270 *
310
250
272
223
267
306
203
281
246
302
266
294
403
430
346
289
372
400
AMMONIA
NITROGEN
CONCEN.
TO AERATION
(MS/L)
============:
! 10.1
7.2
7.1
: 11.4
15.7
9.1
6.4
8.4
: 10.1
10.6
15.7
13.6
13.5
IS. 9
119.2
: 12.4
17.7
18.3
21.9
17.8
16.6
15.4
17.0
14.0
12.8
28.8
i30.5
25.9
21.6
24.4
27.3
18.1
19.1

        »  ESTIMATED VALUE, NO DATA AVAILABLE

NOTE:  FLOW TO AERATION INCLUDES PLANT RECYCLE FLOWS
                       28

-------
               TABLE   6


     SELECTED  PLANT  OPERATION DATA
            v
         (Aeration Tankg 1-3)


MONTHLY AVERAGES
DATE
BOD LOAD
SRT*
Ub/1000 cf,d) (day)
SepteBber, 1985
October, 1985
Noveaber, 1983
December, 1985
January, 1986
February, 1986
March, 1986
flpril, 1986
May, 1986
Jurre, 1986
JuKy, 1986
August, 1986
September, 1986
October, 1986
Noveaber, 1986
December, 1986
January, 1987
February, 1987
March, 1987
April, 1987 '
May, 1987
June, 1987
July, 1987
August, 1987
Septeaber, 1987
October, 1987
Noveaber, 1987
December, 1987
January, 1988
February, 1988
March, 1988
April, 1988
May, 1988
June, 1988
22.5
26.1
35.9
43.0
39.2
31.9
37.6
33.6
32.6
37.1
35.1
27.8
32.1
28.0
24.9
24.9
27.7
21.5
24.0
21.4
27.4
32.5
21.6
31.6
26.0
30.7
25.9
28.1
39.3
41.1
31.4
36.8
32.8
37.3
*
*
«
14.2
25.2
4.6
2.5
5.0
5.3
6.2
8.2
.5.9
4.8
5.4
8.1
7.9
11.8
9.4
9.2
8.0
8.4
5.7
4.6
6.9
7.1
7.6
6.7
5.4
6.5
10.5
10.2
7.0
9.3
7.2
F/M
(day-1)
s=— ==3= ====s:
0.35 1
0.28
0.27
0.38 1
0.40 fl
0.40
0.59 •
0.63
0.49 B
0.39
0.39
0.40-
0.57
0.38
0.26
0.27 Dl
Tl
1 1
0.33
0.27
0.26
0.22
0.31
0.35
0.27 31
0.40
0.38
0.29 OC
0.23
0.27 DE
0.37
0.32
0.22
0.19
0.26
0.28
                                 NOTES
                        BLENDED PE + POND EFFLUENT
                        ALL  FLOW TO EQUALIZATION'POND

                                                i

                        ALL  FLOW  TO  EQUALIZATION !POND
                       BESIN BYPASSINS EQUALIZATION POND
                                JUNE 8th
                       DECEMBER 10th ALL FLOW
                       THROUSH EQUALIZATION POND
                      JULY 31th  THROUSH  SEPTEMBER 24th
                          SEEDINS POND WITH R.A.iS.

                      OCTOBER 20th BESIN BYPASSINS
                          EQUALIZATION POND     '
                      DECEMBER 1st ALL FLOW TO  ''
                          EQUALIZATION POND
    *   Insufficient  waste  record
           29

-------
                                   a
      The restoration of diffusers  in  Tanks 2 and  3 coincided with
 completion o-f the  Tank 1 retrofit, so all three   tanks were in a
  like new" condition at the end  o-f May,  1986.  In eafly July, as
 indicated in Tables 7 and 8, parallel  off gas testing of all three
 basins was  initiated and the  pilot  diffusers  were  installed in
 the  inlet pass  of Tank  2.   The aeration  tanks were  operated
 continuously from late May, 1986,  until June, 1988.  At that time
 each tank was drained and field cleaned,  in situ,  consistent with
 the cleaning procedure  used in 1986.   Diffusers   were once again
 returned to Ewing Engineering Company   in  an "as  found" condition
 for evaluation.                                       j

                                                      i
 Piffuser Fouling - Theoretical Discussion            \

      Before presenting  the results relating to  diffuser fouling
 at Monroe, it is considered fitting to  discuss  the general nature
 of  diffuser fouling as it is measured by BRV and DWP. i

      Dynamic  wet   pressure  (DWP)  is  a  measurement  of  the
 differential   pressure  across  the  porous media  at ,  a  defined
 airflow rate  when the diffuser  is operating in a liquid medium
 (e.g.   tap water  or mixed  liquor).   Due  to the  fact that  the
 surface pores of a  ceramic diffuser  formed by   the irregularly
 shaped  particles making up the ceramic element constitute a range
 of  sizes  and larger  pores produce bubbles  at a  lower pressure
 than smaller pores  of the  same shape,  only the  largest pores
 function.   As a  result, only a relatively small  percentage of the
 surface pores actually  emit bubbles.   The DWP,  which !  is the sum
 of  the   frictional  resistance to  flow through the media  and the
 force to  make bubbles  at the  diffuser surface,   represents the
 lowest  possible  pressure at which the diffuser can operate at the
 airflow in question.                                  ;

     The bubble  release vacuum (BRV)  is a measure of  the pressure
 to   produce  bubbles  at  specific  localized  areas ;across  the
 dif-Fuser surface.   The BRV probe's 25 mm diameter tubje,  which  is
 pressed firmly  against the  surface of  a  wetted dilffuser  and
 sealed  by  a rubber  gasket,  is  evacuated with a  vacuum  pump.  The
 BRV  is  the stable vacuum at  the  diffuser surface required to draw
 air  bubbles from the  diffuser through a column  of liquid  in the
 probe at a flux  rate of  2 scfm/ft=.   Typically, the  average of 9
 such readings are reported as  the mean BRV and standard deviation
 over the mean  is reported, as  is  the coefficient of variation.
                                                      i
     The DWP  of   a  new diffuser at  an   airflow setting  equivalent
to 2  scfm/sq.   ft. of   exposed diffuser surface (about  O.75 cfm
 for the  Monroe diffusers)  is nearly equal  to the  mean!  BRV  value.
The ratio of DWP to BRV  is typically slightly less thah unity for
a new  diffuser.    In   the  case where  fouling  results  in  the
preferential plugging of some pores relative to  others1,  BRV will
30

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                               TABLE  7

                           MONROE,  WISCONSIN


                    CHRQNOL08Y OF  EVENTS  BY CATEGORY
EQUALIZATION
                                           USA6£
JSepteaber 1, 1985 through Deceibar 1, 1985:



Oeceaber 1, 1985 through June 7, 1986:

June 8, 1986 through Oeceaber 9, 1986:



Deceeber 10, 1986 through October 19, 1987:

Octobtr 20,  1987 through Novesber 30, 1987:



Deceaber 1,  1987 through June 30, 1988:
                     Partial flo« to Pond
                     (Blended Priaary Clarifier
                     and Pond Effluent)

                     All floM to Pond

                     Bypassing Pond  ;
                     (Priaary Effluent to
                     Aeration)
                                     i
                     All flow to Pond

                     Bypassing  Pond
                     (Prieary Effluenjt to
                     Aeration)        '

                     All  flow to Pond
              POHD  StEDlHS     (K.A.S.  TO EQUALIZATION POHD)


                July  31,  1987  through  September  24,  1987

                 Decaaber 30,  1987 through  Hay 30,  1988

                   June 24,  1988  through June 26,  1988
                           AHKQHIA  ADD IT I OX


                July 31, 1986 through Decenber 21,  1986

              February 29, 1987 through January 12, 1988

                 Harch 10, 1988 through June 30, 1988

                                31

-------
                         TABLE   7 -  Continued
                            MONROE,  WISCONSIN


                     CHRONOLOGY OF EVENTS BY CATEGORY


                           OFFGAS TES71HB DATES


                September 11,  ,1985            Tanks 1 and  3

                September 19-21,  1985          Tank  3

                December  10-11,  1985           Tanks 2 and  3

                April  9,  1986                  Tanks 2 and  3

                July 8-9,  1986                Tanks 1,  2 and  3

                November  20-21,  1986           Tanks 1,  2 and  3

                March  5,  1987                  Tanks 1,  2 and  3

                August  17-19,  1987            Tanks 1,  2 and  3

                November  3-4,  1987            Tanks 1,  2 and  3
                          P1LQ7 HEADER TEST1HB                '
                                                              i
July 9, 1986s                        Install all 5 pilot headers

November 25 and December 4, 1986:    Remove first set of differs from
                                     pilot headers (0-4.5 month batch).

March 3 and 9, 1987:                 Remove second set of diffusers from
                                     pilot headers (0-8 month and 4.5-8
                                     month diffusers).
                                                              i
July 30 and August 4, 1987:          Remove third set of diffusers from
                                     pilot headers (0-12 monthiand 8-12
                                     month diffusers).        '.
                                                              \
Nuvmeber 6 and 14, 1987:             Remove final set of diffusers from
                                     pilot headers (0-16 month ,and 12-16
                                     month diffusers).        i
                                 32

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                             TABLE   8


                         MONROE,  WISCONSIN

            SEQUENTIAL CHRONOLOGY  OF IMPORTANT EVENTS
September  1,  1985:                                     !
    Begin  partial flow from equalization  pond.         ,
    Aeration  influent blend primary e-f-fluent and pond effluent.

September  4,  1985:
    Aeration  Tank 3 brought on-line with  ceramics.     ;

September  11, 1985:                                    i
    First  offgas analysis of Tank 3.
    Tank 2 down for retrofit,                          !
    Tank 1 on-line with coarse bubble.                 !

September  19-21, 1985:
    Comprehensive offgas evaluation of  Tank  3.         ;
    Single offgas survey of Tank  1  coarse bubble.      :
    Tank 2 down for retrofit.                          i
    Aeration  influent from primaries and  pond.         :

November 25,  1985:                                     I
    Tank 2 started up with ceramic  grid system.

December 1, 1985:                                      '
    All flow  now through primaries  to equalization  pond  to
    aeration  tanks.                                    j

December 10-11, 1985:                                  i
    Offgas analysis of Tanks 2 and  3.                  <
    Tank 1 down for retrofit.                          i
    Aeration  tank influent from primaries through pond.

April 9, 1986:                                         :
    Offgas analysis of Tanks 2 and  3.
    Tank 1 down for retrofit.                          !
    All flow through equalization pond.                '

May 12, 1986:                                          \
    Aeration Tank 2 drained after 168 days of operation.
    Sample diffusers taken to Ewing Engineering  Company  for
    analysis.                                          ,
    Tank hosed, acid sprayed, hand  brushed and re-hosed  prior to
    bringing on—line.                                  !
                              33

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                      TABLE  8 -  Continued            i
Monroe, Wisconsin Sequential Chronology                i


May 22, 1986:                                          ;
    Aeration Tank 3 drained after 26O  days of  operation.
    Sample diffusers taken to Ewing  Engineering Company for
    analysis.                                          j
    Tank hosed, acid sprayed, hand brushed and re-hosed prior to
    bringing on-line.                                  |

June 6, 19S6:
    All three aeration tanks on-line with  cleaned  or new ceramic
    discs.                                             :

June 8, 1986:
    Equalization tank out of service to install  coarse| bubble
   •' diffused aeration.                                 i
    All pond to aeration from primary  clarifiers.      '

July 8-9, 1986:                                        !
    Offgas analysis of aeration Tanks  1-3.             i
    Influent is from primary clarifiers.   Pond out of 'service.

July 9, 1986:                                          |
    5 sets of pilot diffuser headers installed in  Pass 1  of Tank
    2.                                                 ;
                                                       i
July 31, 1986:
    Begin supplemental ammonia addition on an  intermittent basis,
    to aeration influent 
-------
                       TABLE  8 -Continued            \
 Monroe,  Wisconsin Sequential  Chronology               i


 Mari:h 5, 1987:
     Offgas analysis of  Tanks  1-3.
     Influent to aeration is from the equalization pond.

 July 31, 1987s                                         j
     Begin seeding equalization pond with return activated sludge.

 July 30  & August 4,  1987:                              !
     Remove the  third set of diffusers from pilot headers (O-12
     month and 8-12 month diffusers).                   i

 August 17-19, 1987:                                    !
     Offgas analysis of  Tanks  1-3.                      I
     Influent to aeration from the  equalization pond with R.A.S.
     addition to pond.

 October  20,  1987:                                      :
     Cease use of  equalization pond.
     Primary effluent to aeration tanks.                ;

 November 3-4, 1987:                                    \
     Final  offgas  analysis  of  Tanks i-3.                ;
     Influent from primary  clarifisrs.                  !

 November 6 & 14,  1987:
     Remove final  set of  diffusers  from pilot headers Cb-16 month
     and  12-16 month  diffusers}.

 December 1,  1987:                                      ;
     All  flow through equalization  pond to aeration.    !

 January  12,  1988:
     Cease  supplemental ammonia addition.               ;

 March 10,  1988:                                        !
     Initiate supplemental  ammonia  addition.            i

 June  13  1988:                                          I
     Aeration Tank  1  drained after  24 months  of  continuous
     operation.
    Sample diffusers sent  to  Ewing  Engineering  Company Ifor
     analysis.                                          I
    1                    '                              i'
June 20,   1988:                                         i
    Aeration Tank 2  drained after 24 months  of  continuous
    operation.
    Sample diffusers sent to  Ewing  Engineering  Company for
    analysis..
                                35

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                      TABLE  8 - Continued            \
                                                      i
Monroe, Wisconsin Sequential Chronology               '


June 29, 1988:                                        \
    Aeration Tank 3 drained after 24 months of continuous
    operation.                                        |
    Sample diffuser sent to Ewing Engineering Company
    analysis.
                          END OF INVESTIGATION
                                36

-------
increase much more rapidly  than  DWP,  causing  the DWP/BRV ratio to
decline.  In this case, the mean BRV  is significantly|higher  than
the DWP because pores inside  the  BRV probe,  which may be largely
plugged, are forced  to operate  whether or  not   they emit bubbles
when the di-f-fuser is operated as a whole.             '

     In  the  unique  case  of fouling  caused   only I by  calcium
carbonate precipitation,  where  all the  pores  foul  more  or  less
uniformly, the  BRV and  DWP  tend to   increase  similarly  and the
DWP/BRV ratio remains relatively constant.
                                                      i
     The ratio of DWP to BRV,  both measured at  the same air flux,
may  be a  more  meaningful indicator  of   diffuser  fouling   than
either parameter  alone.  Upon   closer examination,   DWP measures
the  overall pressure  that is  available   to form  bubbles at  a
specific air flux over the  entire diffuser surface.  iBRV, on the
other hand,  measures the   average pressure  that is irequired to
form bubbles at a specific  air   flux  over a limited  region of the
diffuser surface.   Consequently, bubbles will  form   at a reduced
flux, if at all, at any point  where the BRV exceeds  the DWP.

     The DWP to  BRV ratio  is closely related to  thejfraction of
the diffuser  area that  is actually   emitting  bubbles.    As  this
ratio decreases,  less effective area  is available  for  the  same
diffuser  airflow.  This  results  in higher  localized air   flux
rates on the diffuser  surface,  potentially causing  the formation
of coarser bubbles with a   corresponding reduction in OTE.  Thus,
a decrease in  the DWP/BRV  ratio  due to diffuser fouling may be
more indicative  of fouling   induced  OTE losses than i  changes in
either parameter alone.                               i
                                                      i

Pilot Diffuser Study                                  j         .

     In order  to meet  the primary objective  of  this  study,  to
evaluate the OTE and fouling  characteristics  of  ceramic diffusers
over a wide range of  effective  pore  sizes, the  investigation was
divided into two main areas.   One was the long-term  monitoring of
full-scale OTE  and evaluation of diffusers  upon  tank draindown,
and the other was the  evaluation of  performance of  tl^e diffusers
of  the various  effective  pore sizes  which  were  monitored  on
removable pilot headers.  Changes in   OTE,  DWP,  BRV,  and air  flow
Profile  were monitored,  and the  resulting  foulant   analysed on
intervals of approximately  4  months,  up to  a  cumulative period of
16 months.                                            :
                                                      i
     A total  of five independent pilot headers,  each containing
four ceramic discs,  were installed in the  inlet pass  of Tank 2,
as shown in Figure 13.  Four of  the pilot units  were  used for the
four different  diffuser permeabilities investigated.    The fifth
                               37

-------
                       FIGURE   S3
                 MONROE, WISCONSIN              \


                    MONROE PILOT DIFFUSERS                 j

ALL FIVE PILOT HEADERS WERE INSTALLED ON JULY 9,1986 AT ABOUT 3iPM

                        TANK   2                      !
                    WASTE
                    FEED
                   WASTE
                    FEED
            PILOT
             UNIT
                   WASTE
                   FEED
 i SERIES INTER-PUNT
9    FOULING UNIT
T 26 SP PERM, BRV06
-**              PRW. EFF
 i   SERIES
4   K35-67
T 38 SP PERM, BRV04
                              i
                              4
                              '
    SERIES
   K35-68
  50 SP PERM, BRV03
                                 SERIES
                                 K35-65
                                14 SP PERM, BRV09
                 PRIM. EFF
                                 SERIES
                                 K35-66
                               26 SP PERM, 6RV06
                PRIM. EFF
         MIXED UQUOR
           R.A.S.
                         38

-------
 pilot  was part  of an  interplant -fouling  study which   included
 similar  pilot headers  at several  test sites  to ascertain   the
 relative -fouling  tendencies of the various  plants studied.   The
 results of the interplant study  is being presented in a  separate
 report.                                              ;       K
                                                      !
      A drawing  of a  typical pilot  unit provided  by Sanitains
 commonly referred  to as a  4-lunger, is presented in;  Figure  14.
 Each  pilot header  is supported  from the  handrail system by a
 rigid  frame  made  of  unistrut, such  that  the  di>fusers   are
 submerged about  6 ft. Air for  the diffusers was tapped  off  the
 air  main.   Plant staff  monitored pilot headers,  control ing  the
 air  flow to each diffuser at  about l.O cfm. Periodic in situ  DWP
 measurements were made on approximately a weekly basi4.

      As  in the  interplant fouling  study,  one  of the  diffuser
 holders was isolated from the other  three and had a Separate  air
 feed line.    The modification permitted a  new diffuser,  possibly
 having a DWP substantially lower  than the other diffusers, to be
 installed on the  4-lunger without affecting the air ^flow to the
 other three diffusers being fed from a common air source.

       The duration of  the test  from the first tank drfaindown was
 scheduled to be 16 months.   Sampling of diffusers were planned on
 four  month or   quarterly (based  on the  duration of !  the study)
 intervals according to the following schedule:        [

           After  4  months  of  operation,  one diffuser frfom  each
      pilot unit  was removed and  a new diffuser  element  was
      added;  after   an  additional   4 month period,   a diffuser
      that had operated 8 months was removed,  as  well'  as  the
      diffuser added  to the  header   4 months earlier !and  one
      new diffuser  was  added  to the  header.   This sequence  was
      repeated after   12 months  and finally  after   16 imonths,
      when a 4 month  and 16 month diffuser were removed.

      Using   the   above   technique,   four    diffusers!  providing
 information on  the  cumulative effect  of fouling  after 4,  8,  12
 and  16 months of service were  obtained,  as well  as four diffusers
 indicating  the fouling  tendencies of  the system for  4 ^independent
 4 month  intervals.   The  later  4  units  were  used  to appraise the
 relative variability  of the fouling   experience at  the  plant  in
 question.                                             !

     The  testing  sequence  used   in   evaluating  all  diffusers
 removed  from Monroe  follows.   In  order  to test  diffusers from all
 five 4-1angers, two trips were  made one  week apart.  Oh one  week,
 diffusers from two  pilot headers were removed   and thte following
week samples were taken from the remaining pilots.   Ini all cases
removed diffusers  were labeled, carefully slipped  into zip-lock
bags  and  returned to  Ewing  Engineering  Company in:  Milwaukee
                               39

-------
40

-------
 within  three  hours.    Steady-state  clean water  OTE 'tests  were
 conducted   the same  day  immediately  after photographing?   The

 and ?oul? ^  °WP?  BRV'  a0d  "^  fl°W Pr°file t«st«9«4e conducted
 and foulant scrapings  were  taken.   In some  cases, the diffusers
 were subsequently cleaned  and  retested.                j  Q1Trusers
                                                        i

      The initial diffuser  characteristics  of the pilot diffusers
 Jr^: ?*W were,  Previously  presented in Table  i.  Summarized datl
 JA   i V llpt  dlffuser  evaluations  are presented in JTables 9 to
 14 and  Figures 15  to   18.   The  figures,  which  present quarterly
 and  cumulative plots  of  DWP,   BRV and   clean water  lOTE of  the
 Pilot Study - Figure 15
     Figure 15  indicates the results  of  the group  o^f  diffusers
having a specific  permeability of about  14 and BRV0  tof about 9

liL™  TH   ^^ Partravs the DWP>  BRV  and OTE as a function oi
time.   The  squares  represent  the quarterly  data,  iwhile  the
InJfSlH   represent  cumulative   changes  ^n  th4 \  plrLeter
 indicated.
 i-   + IhS/irSL 9r°UP °*  pilot di** users  were removed  from  the
 test header after about 4.5 months of continuous service.  Suring
 this period,  the  BRV rose by a factor of  greater than two, frCm
 8.8 in   wg  to  23.2 in.  wg. The DWP at  O.75 scfm per diffuser
 (approximately 2 scfm/sq.  ft.) rose  to only about l.i times  Ki
 initial  value, while  the clean water OTE of  the fouiJd defuse?
 dropped  from  19.0%  to 12.4% at l.O scfm per  diffused  Thusfat
 O  ?5 iTif« '   f- rfmral '  thiS di^ussr •«* performing  at about
 hid h           ^i  trans'fer efficiency.   Since only ohe diffuser
 had been  removed from each pilot  at the 4.5 month  point  these
 data  represent both  quarterly  and cumulative  effects and  a?e
 therefore plotted as the same point.                    j

      At  the 8  month  point,  one  diffuser  operating froJ. zero to 8

                     -
     The  BRV, DWP  and OTE   data  all   indicate that  iihe fouling
                                                            °
 hanh                    '                       was   ss=
than the O to 4.5 month interval.  During the second quarter  BRV
increased from about  8.8  in.  wg. new  to 13.9  in.   w5   fouled
compared  to 23,2  in.  wg.  after  the first  quarter?  The
              cnb
new to about 17% m^" x^ thS °TE   dscrsas^ *"» |2O.5% when
of service               °*  3 """ diffuser>  following 3.5 months
                               41

-------
                 TABLE     9






MONROE PILOT OIFFUSERS AFTER  APPROXIMATELY 4.5 MONTHS AERATION






      • SUMMARY OF DIFFUSER CHARACTERIZATION DATA

DIFFUSER
NO.


K35-65-1
K35-6S-1

K35-66-3
K35-66-3

K35-67-1
K35-67-1

K35-68-1
K35-6B-1

TYPE DIFFUSER j TJN£ IN

SP. PERM
14
14

26
26

38
38

50-
50

	 	 CONDITION ! SERVICE
BRV0 j'
' 1
9 ! NEU !
9 ! AS RCVD ! 4.5 MOS
J 1
J 1
6 i NEK !
6 i AS RCVD i 4.5 MDS
} . j
I ,
4 i NEK !
4 i AS RCVD ! 4.5 MOS
j 1
1 '
31 NEK !
3 i AS RCVD ! 4.5 MOS
J '
BRV
(in. »g.)

8.76
23.24

5.70
12.97

4.06

2.70
10,91


C.O.V.

0.032
0.218

0.033
0.151

0.025

0.049
0.165

DKP (in. »g.)
0.50
cfi
7.10
7.20

4.80
6.70

3.50
5.10

2.70
3.70

0.75
cfi
7.65
9.95

5.05
6.95

3.70
6.10

2.85
4.20

2.00
CfB
9.00
17.80

5.90
10.60

4.20
9.25

3.15
6.05

3:.10
cfi
10.55
35.00

6.30
16.10

4.80
16.00

3.60
10.75
•, • rf
RATIO
DKP/8RV

0.873
0.428

0.386
0.536

0.911

1.056
0.385

                        42

-------
                   TABLE   10
HONROE PILOT DIFFUSERS AFTER APPROXIMATELY 8.0 MONTHS AERATION






       SUMMARY OF DIFFUSER CHARACTERIZATION DATA

DIFFUSER
un
NU.
	
K35-65-6
K35-65-6

K35-65-3
05-65-3

K35-67-6
K35-67-6


K35-67-3
K35-67-3

K43-67-2

K35-66-4
K35-66-4
K43-57-1
K3S-68-3
K35-68-3







TYPE DIFFUSER i

SP. PER
14
14

14
14

38
38


38
38

26

26
26
50
50
50







	 , CONDITION
BRVo !
1
9 ! NEK
9 i AS RCVD
1
9 i NEK
9 i AS RCVD
1
4 ! NEK
4 ! AS RCVD
!
1
4 i NEK
4 ! AS RCVD
,
6 ! AS RCVD
I
1
i ! NEK
S ! AS RCVD
3 ! AS SCVD
3 i NEK
3 i AS RCVD

I
,
,
,
',
1
TIME IN
SERVICE


3.5 HOS

8 HOS


3.5 MOS


8 MOS

3.5 HOS

8 MOS
3.5 MOS
8 HOS







BRV
(in. Kg


13.9

8.7
15.9


5.4


3.93
8.98

7.93

5.76
12.48
5.07
2.78
5.44








C.O.V.


0,21

0.03
0.15


0.056


0.028
0.182

0.061

0.039
0.105
0.236
0.043
0.145







DKP (in. ag.i '
' 0.50 i 0.75 i 2.00 i 3.10
eft

6.3

7.1
7.3


3.55


3.40
5.05

5.10

4.75
5.60
3.15
2.60
2.70







cti ! cfi j cfs
1 i
' I
I i
7.80 ! - !
. 7.45 ! 9.35 j
1 i,
7.65 ! 9.25 I, 10.7
9.10 ! 13.55 ',',
i !;
t i!
3.85 ! 4.60 !|
{ '

; i i
3.60 ! 4.05 ! ; 4.55
6.05 ! 10.30 i ,
J . 1 !
5.60 ! 7.10 i! -
! j :
r j [
5.00 1 5.85 ! ! 6.70
7.10 i il.70 ! , --
1 i
•3.45 ! 4.40 ! j -
2.75 ! 2.95 ! ; 3.35
3.15 ! 4.55 ! ! --
1 1 !

! i i
1 ' '
i { 1
j i '
i [ '
RATIO !
DKP/8RV !
t
	 -:
0.536 !
, 1
0.873 !
0.570 !
1
j
0.704 !
1

i
0.916 i
0.674 !
,
0.706 !
t
0.868 !
0.569 !
0.680 i
0.989 !
0.579 i

•
',
1
• i
!
i
                    43

-------
            TABLE    11
PILOT OIFFUSERS AFTER APPROXIHATELY  12.0 HONTHS AERATION




   SUMMARY  OF DIFFUSER CHARACTERIZATION DATA

DIFFUSES
NO.
K35-66-3
K35-66-3
K35-66-3
K35-66-5
K35-66-5
K35-66-5



K35-68-1
K35-68-1
K35-68-1
K35-68-4
K35-68-4 '
(C35-68-4


K35-65-1
K35-65-1
K35-65-1
K35-65-4
K35-45-4
K35-65-4
TYPE DIFFUSER
SP. PER
26
26
26
26
26



50
50
50
50
•50
50


14
14
14
14
14
14



35-67-1 38
35-67-1 38
35-67-1 38

31J-67-5 38
3K-67-5 38
35-67-5 38
BRVo
6
6
6
6
6
6



3
3
3
3
3
3


9
9
9
9
9
9



4
4
4

4
4
4
CONDITION
NEK
AS RCVD
AFTER H-A-H
NEK
AS RCVD
AFTER H-A-H



NEH
AS RCVD
AFTER H-A-H
NEK
AS RCVD
AFTES H-A-H


NEK
AS 8CVD
AFTER H-A-H
NEK
AS RCVD
AFTER H-A-H



NEK
AS RCVD
iFTER H-A-H

NEK
AS RCVD
FTER H-A-H
TIHE IN
SERVICE
NEK
4 HOS.
NEK
12 HOS.



NEK
4 HOS.
.SEK
12 HOS.


NEK
4 HOS.
1
NEK
12 HOS.



NEK
4 HOS.

NEK
12 HOS.
BIS : • ; MP (i"-~«s-> rW
fin. »g.) ! C.O.V. ! 0.50
! ! cfi
5.70 ! 0.033 ! 4.80
8.08 i 0.079 ! 5.85
5.56 ! 0.053 ! 4.75
J 1
5.69 ! 0.011 ! 4.75
12.39 ! 0.075 ! 6.40
5.63 ! 0.032 ! 5.15
J 1
j 1
J 1
1 ' 1
t ,
2.70 ! 0.049 ! 2.70
7-17 ! 0.137 ! 3.85
2.71 ! 0.085 ! 2.95
t j
2.68 ! 0.052 ! 2.65
9.21 ! 0.108 ! 4.05 !
2.78 ! 0.047 ! 3.05 !
0.75 ! 2.00 ! 3.10 ! DKP/BRV
cfi ! cf« eft !
5.05 i 5.90 6.80 ! 0.886
4.55 ! 7.70 10.05 ! 0.811
4.95 ! 5.60 6.40 ! 0.890
5.05 ! 5.90 6.85 ! 0.818
7.35 ! 9.55 14.25 ! 0.593
. 5.30 ! 6.35 7.70 > 0.941
! I
I ' ' i
1 i ' '
2.85 ! 3.15J! 3.60 ! 1.056
4.30 ! 5.40 ! 8.15 ! 0.600
3.00 ! 3.-80 ! 4.00 ! 1.107
2.8.0 ! -2.95 ! . 3.35 ! 1,045
4.85 ! 6.75 J! 10.85 ! 0.527
3.20 ! 3.40 ! 3.95 ! 1.151
1 ! j ! • | i
!'.';. I ; j j
1 !!!;,'
8.76 ! 0.032 ! 7.10 ! 7.65 ! 9.00 ! 10 55 ' 0 87'
14.22 ! 0.095 ! 8.90 ! 9.85 ! 11 45 j ' '90 •' I'w
9-01! 0.032! 7.35! 7.80! 9.10!; 10~90 i 0.866
24*08 ! 0*150 ' 7'°° • M° '' 8'85 10'25 ' °'829
8,69! 0.035.! 7.65! 3.10 9.'65 \ H.'S ! I'.m
\ ' .;..._, '<
» * *
i , , '
I'll- I'^i hsr 3-7° 4-2° ; 4-80 «•»»
4 o" : D m i'SJ ; i<55 7-95 i n-20 °-745
4.0. , 0.037 ! 3.95 ! 4.15 5.05 | 5.60 1.032
3-91 ! 0.055 ! 3.55 ! 3.80 4.30 ' 4 80 0 972
13.^8 ! 0.175 ! 7.20 ! 8.15 10.40 ! 16*85 o'(i(19
4 tl t ft nt, . _ ._ . *V«TV 1O.OW V.DUJ
•"" , v.uis i j.65! 3.75 4.55 ; 5_35 0 B99
            44

-------
                  TABLE   12






«ONROE PILOT DIFFUSERS AFJER APPRO!IHATELV 16.0 HONTHS AERATION






        SliNKARY OF  DIFFUSER CHARACTERIZATION DATA
~ 	 	 — — 	 	 — _ 	 	 	 __„__. 	 ..___ 	 ___ j
DIFFUSER
NO


K35-65-5
K35-65-5
K35-65-5

K35-65-6
((35-65-6
K35-65-6


K35-67-4
K35-67-4
K35-67-4
K35-67-6
K35-67-6

K35-66-8
K35-66-8
.K35-66-B
K35-66-6
K35-64-6
(C35-66-6

K35-68-6
K35-6B-6
K35-68-5
K35-68-5
K35-68-5
TYPE DIFFUSER !

SP. PE
14
14
14

14
14
14


38
38
38
38
•*n

26
26
26
26
26
26

50
50
50
50
50
	 . mflfljjjj]
i
BRV0 !
9 ' NFy
9 ! AS RCVD
9 ! AFTER H-fl-
I
9 ! NEK
9 ! AS RCVD
9 ! AFTER H-A-
1

i
4 ! NEK
4 ! AS RCVD
4 i AFTER H-A-H
4 i AS RCVD
4 ! AFTER H-A-H
j
4 ! NEK
4 i AS RCVD
4 ! AFTER H-A-H
r
4 ! NEK
4 ! AS RCVD
4 ! AFTER H-A-H
1
3 ! AS RCVD
3 ! AFTER H-A-H
I
3 ! NEH
3 ! AS RCVD
3 i AFTER H-A-H
TINE IN
SERVICE


16 HOS


4 HOS


16 HOS
4 HOS

4 HOS
16 HOS

4 HOS
16 HOS
BRV i ! m? (in' "9-) ' '' MTI0
«n. *g.l ! C.O.V. ! 0.50 ! 0.75 ! 2.00 ! 3.10 i DUP/M
1 ; ci J rf. ! eft ,! Ef. :
1 t | ' ' I
8.69 ! 0.032 i 7.25 ! 7.90 ! 9 45
27.86 ! 0.158 ! 10.10 i 13.10 ! 1B.'?5
9.60 ! 0.070 ! 7.25 ! 8.00 i 9.20
i 'it
* • I
1 * ' *
17.43 ! 0.195 ! 7.10 ! 8.10 ! 9.40
9.24 ! 0.067 i 6.65 i 7.30 ! 8.70


4-33 ! 0.033 ! 3.65 ! 3.85 ! 4.40
2.81 ! 0.131 ! 4.50 ! 4.95 ! 5.60
4.47 ! 0.036 ! 4.05 ! 4.45 ! 5.05
• '' ' > I •
B.28 ! 0.106 ! 3.95 ! 4.40 i 5.20
4.23 ! 0.077 f 3.35 i 3.75 ! 4.20
1 ' 1
5.64 ! 0.024 ! 4.75 i 5.05 i 5 75 \
9.37 ! 0.105 ! 5.30 ! 5.80 ! 6.10 i
5.98! 0.032! 4.80! 5.20'l 6.00!
10.65 ! 0.909
35.50 ! 0.470
i 10.95 1 0.833
1
1
12.50 ! 0.465
10.75 ! 0.790

j
5.05 i 0.889
7.60 ! 0.562
4.45 ! 0,996
7.20 i 0.531
5..15 ! 0.886
1
4.90 ! 0.895
8.90 ! 0.619
7.15 ! 0.870
1 ! ! ! !
5.60 ! 0.051 ! 4.85 i 5.20 ! 6.05 6.70 ! 0 929
I- 0.142! 6.65! 7.60! 9.30 ,4.60 0.
4.20 0.071 ! 5.25 ! 5.75 ! 6.65 8.40 ! 0.927

4.71 ! 0.120! 3.00 ! 3.451 4.30 ! 6.50 ! 0514
2.80 I- 0.074 ! 2.45 ! 2.75 1 2.95 \ 3.55 ! 0.982
1 ' ' 1 '
2.71 ! 0.103 ! 2.50 1 2.70 ! 2.95 3.30 ! 0 996
, «M!! 2>85! 3-15! 3-50 «•»>•
2.97! 0.071! 2.60! 2.90! 3.15! 3.80! 0976
                   45

-------
T A B L E 13 ,
ESTIMATED AfciRASE OTE FOR RUN
BASED ON CUMULATIVE i
! BRVo

i
i TIME IN
! SERVICE
NEN
4.5 MO.
NEW
8.0 MO.
NEW
12.0 MO.



NEW
16.0 MO.

!

9

14
SPECIFIC PERM
SOTE
0.190
0.124
0.205
0.168
0.200
0.197



0.205
0.125

.161

ESTIMATED !
AVERAGE !
LEAN WATER! 0.200
! OTE !
RATIO
0.65
0.82
0.99



0.61

0.80




:
6 ; 4 ! 3
26 1 38
SPECIFIC PERM ! SPECIFIC PERM
SOTE ! RATIO
0.185
0.98
0.182
0.200
0.82
0.165
0.195 !
! 0..92
0.179 !
1
1
1
1
0.195
0.71
0.138

.170 0.88



0.194 !
! !
SOTE ! RATIO
0.175 !
! 0.97
0.170
0.190
0.162
0.185
0.199



0.190
0.132

.167



0.185
. ! I 	 1 I. !
0.85
1.07



0.69

0.90




I
50
SPECIFIC PERM
SOTE !| RATIO
i,
0. 163 !
: 1.01
0.165 ;
0.180 j
. 0.82
0.147 ;
0.175 i
: i.oo
0.175 ! ;
1 '

. 1 i
1 ' " •
o.iso :
! ' 0.64
O.U6 i ;
i
! i
•153 i i 0.87
! i
> i '
i '
t i
! '
0.175 ! '
i ;
NOTES:    SOTE   -   STANDARD OXYBEN TRANSFER EFFICIENCY  IN
                    CLEANWATER AT 1.0 CFM PER DIFFUSER
         RATIO    -   CLEAN WATER SOTE AFTER  SERVICE TO SOTE
                    WHEN  NEW
                                 46

-------
                                   TABLE    14

                          ESTIMATED AVERAGE OTE BASED ON
                 4.0 MONTH AVERA6ES AND 4.0 MONTH HOSE-ACID-HOSE
                               WITH FUU RESTORATION
> SKVo


TIME IN
SERVICE
NEW
0-4.5 MO.
1
1

f
1
! NEW
14.5 - 8.0 MO.
!

I NEW
!S.O - 12.0 MO
!


NEH
12.0 - 16.0 MO
OTE

!* AV8.
i 16 MO. OTE
1
• OTE
I
I
! ESTIMATED
' ! ' i « !
14 j ., ' j
SPECIFIC PERM ' ^PPrrcTp 38 j 50 |
	 !—--.-._„_. ! SPECIFIC PER" ! SPECIFIC PERM !
SOTE ! RATIO ! 80TE""rRATro"i""sOTr"rRATIo"i~80TE""""RATIo""
O-l'O i i 0.185 !
1 0.65 ! i 0 98
0.124 ! j 0.182 !
1 ' i

' i !
0-205 ! ! 0.200 !
1 0.85 i [. 0.88
0-175 ! ! 0.175 !
'• : i
I ' '
0.200 ! i 0.195 !
1 0.98 i !
0.197 ! ! — .
! . !
! • j

1 | j
0.205 ! i 0.195 !
! 0.80 ! ! 0.66
0.165 ! ! 0.128 !
• 1 I -
0.183 1 0.92 . 0.180 ! 0.93
j 1
1
r ,
0.161 ! 0.80 0.170 i . 0.88
f f
0.172 ! 0.86 0.175 i 0.90
1 1
i ,
1
! AVERA6E ! |
i CLEAN WATER ! 0.200 ! 0.194 !
-j 	 , 	
1 0.175 ! • 0.163 i
! 0.97 i ' ! 1 01
0-170 ! ! 0.165 I
1 | '
i ! >
' 1 !
! ! :
0.190 ! j 0.180 !
! 0.83 ! i o 79
0.158 ! ! o.U2 !
1 1 !
i !
i
0.185 1
! 0.95
0.176 i
!
!

0.190
0.130
0.172


0.167

0.169





0.68
0.93


0.90

0.91




!
0.185 i
1 ; i
1 0.175 1
i 0.91 i
0.159 ! i
'• !

1
0.180
0.128
0.161
!


0.153

0.157:




0.175
! I
!
! 0.71 !
1
	 ,
0.92 !
j
i
0.87

0.90





OTE ' ! : : s | j
NOTES:      SOTE   -    STANDARD  OXVSEN  TRANSFER  EFFICIENCY  IN
                       CLEANWATER  AT  1.0 CFM PER DIFFUSE?
                                             SERVICE T0

                   -  DATA FROM TABLE 13 ON CUMULATIVE OTE
                                 47

-------
                      FIGURE  IS
                  MONROE, WISCONSIN
 ,BRV
 (in.wg.)
 V
  m
         50

         25

         20


         15
 10
  \
  0
  7
  6

  5

  4
  OTE
(DECIMAL)
0.200
0.175
0.150

0.125

0.100
                      - 14
                         UNITS
                                              A CUMUUT1VE
                                              D QUARTERLY
          •mr
                s,

                                  t-
                      45      8.0       12.0
                             THE (MONTHS)
                       48
                                             DWP
                                         16,0

-------
      The diffuser that had been in  operation for a -full 8 months
 was only slightly  more -fouled than the unit which  had only been
 in service -for the second quarter (3.5 months).
                                                      i   •   ,
      At  the 12  month point,  the cumulative  diffuser was  only
 slightly more  fouled based  on BRV  and DWP  than wab  the first
 diffuser, removed at the 4.5 month mark.  The quarterly diffuser,
 operated from the 8th to the  12th month, was fouled to about the
 same extent as the diffuser from  the second quarter.  The QTE of
 the 12 month diffuser was essentially equivalent to that of a new
 diffuser.  As will  be discussed in another part  of this report,
 the foulant was observed to be thinner at this point in time than
 at  any  other removal  period,  and  may partially  explain  the
 relatively high  OTE values relative  to new.  BOD  loadings, SRT
 and F/M  ratios summarized in  Table 6 suggest  similar operating
 conditions existed  during this  operating period as 'compared to
 the others.                                           ;

      At the end of 16 months,  the BRV was 27.9 in.   wg.  compared
 to 24.1 in.   wg.  after 12 months,  and 8.7 in.  wg. when new.   The
 DWP at 0.75 scfm was 13.1 in.  wg.  at the 16 month mark,  compared
 to  10.2 in.    wg.  at  12.O months,   and 7.4  in.  wg;   when new.
 However, the OTE of  the  16 month  cumulative diffuser dropped off
 significantly from that of the 12 month unit.

      During  the fourth quarter (from month 12 to 16),!the fouling
 tendency was generally equivalent  to that observed for  the second
 and third quarters.                                   |

      The limited   amount of diversion between  the cumulative and
 quarterly results  gives indication   that the effects  of fouling
 upon  DWP  and  BRV  approach a  substantially stable  condition of
 equilibrium  within  about four months.


 Pilot  Study  -  General                                 !

      The above discussion of  Figure   15 indicates how this series
 of  -(Figures  is to be  interpreted, and in  addition,  demonstrates
 the dynamics of the  fouling phenomenon.   During  the course of  the
 pilot  work,  the  character of the  foulant changed significantly.
 After  the  first quarter,  the  diffusers and associated piping  were
 covered  with a frothy  slime about  1/4 inch thick,  whereas at  the
 8,  12,   and  16 month   points,  the foulants were   somewhat  thinner
 and  of   an apparently  tougher  consistency.    It wa4  initially
 thought  that since the plant   is generally deficient  in nitrogen,
 and supplemental  ammonia addition was  not  applied in  a continuous
and  reliable  fashion  during  the first   quarter, that  nutrient
 limiting conditions  may  have   contributed  to the greater apparent
fouling  during the first  4.5  months of  the pilot  work.:  A  careful
                               49

-------
 review  o-f  Tables  5  and  6  suggest,   however,   that  adequate
 nitrogen, in the  form of ammonia,  did  exist in  the waste stream
 entering  the activated  sludge process.    It may   bejsignificant
 that during this period the  equalization pond was out of service
 due  to the installation of diffused aeration in the pond.

      Although the BOD  loadings, as indicated in Table  6, do not
 appear to differ in a significant way from the loadings when  flow
 equalisation was  being practiced, the  variability  of  conditions
 encountered  when  not  employing   flow   equalization   may  have
 contributed to the greater apparent  fouling during the first 4.5
 months of the pilot diffuser study.     •              !

      Figures 16, 17 and IS show the same  general trends described
 in detail -far the 14 permeability 
-------
   BRV
   o
   DWP
                       FIGURE  16
                   MONROE, WISCONSIN
                       - 26 SP
, OTE ,
(DECIMAL)
                                               A CUMULATIVE
                                               D QUARTERLY
4.5      8.0  /     110
       THE  (MONTHS)
                                                 16J)
                        51

-------
     FIGURE  17
mm, WISCONSIN
30
20
15
BRV
(in.wg.) JM
V 10
DWP 9
8
7
6
5
4 1
3
0.200
0.175 1
(DECiAL) °-150
0.125
0.100
* OM\VJ ~









i/m
Lr





jo or rcj








^
\



"~ " — ~~c:


1 Wil3 A CIWULAM
Q QUARTERLY



X
I/
^
^
sf J
K /
/


JJ^






^^y
RRY^s

X
k N|WP
Nl*K
S


k.
^xX.
X,

















   4.5      8.0  /     12.0
          M  (MONTHS)
16.0
     52

-------
                    FIGURE  18
                MO/VfiOf, WISCONSIN
             3 BRVfO) -  50 SP PERM UNITS
       25

       20
 BRV
(tup.)

 DWP
8
7
6

5
OTE
      0.175
      0.100
                                               A CUMULATIVE
                                               D QUARTERLY
                BRV
\
                                              BRV
                                    -m-
                                        \
                    45
                              8.0 t     12.0
                             TiE (MONTHS)
                                         16.0
                      53

-------
      -   Diffusers  of   all   four  BRV0's  tested  follow  similar
         patterns with  time.
                                                      i
         On  the  basis  of  operating pressure  
-------
                                  TABLE 15
FOULANT ANALYSIS - MONROE PILOT DIFFUSERS
TIME IN SERVICE
(Months)
0.0-4.5
4.5-8.0
0.0-8,0
8.0-12.0
0.0-12.0
12.0-16.0
0.0-16.0 i
i
I SOLIDS DEPOSITION
<8)g/cffl2)
13
9
55
8
10
26
22
VOLATILE FRACTION
33
'
41
36
52
46
36.
41 !
ACID SOLUBLE
i FRACTION
' 18
i 22
1 24
"' 25 '
! 24
1 18
! 18
                                 55

-------
Pilot Diff user  Cleanabilitv

     Following  diff user  testing to evaluate the degree and effect
of -fouling  on the pilot  diffusers  removed after 12 and 16 months
of  continuous   service,   each  di-ffuser  was   cleaned  by  the
hose-acid-hose   
-------
 ll-S«p-85    1200     3.1      3.1



 ll-Sep-85    1305     3.2      3.1




 ll-Ssp-85    1313     3.3      3.2



 H-Sgp-BS    1344     3.4      3.2



 ll-Sep-85    1354     3.5      3.3



 ll-Sip-85    1327     3.6      3.3



 Il-Sep-85    1319     3.7      3.4



ll-S«p-85    1221     3.8      3.4
                                                              TABLE    lt>




                                              HONROE    FULL-SCALE    DTE    DATA



                                                           GRID  VERSUS CALENDAR TIME
 0.391     20.0



 0.506     20.0



 0.403     20.0



 0.425     20.0



 0.384     20.0



 0.415     20.0



0.455     20.0



0.393     20.0
 3.7



 3.7




 4.2



 5.3



 7.7



 8.4



8.7



8.8
 1.96








 2.02



 2.13



 1.92



2.08



2.28



1.97
 26



 26



 26



 26



 26



 26



26



26
 6   .








 6



 6



 6



 6



 6



6
0.0479 0.0766
0.0648 0.1036
0.0559 0.0961
0.0519 0.1101
0.0292 0,1214
0.0305 0.1762
0.0280
0.0288
0.1942
0.2069
™ ••—••"- «_oa 3
0.30
0.42
0.38
0.44
0.47
0.70
0.78
0.81
                                                          57

-------
             TABLE   17





I BURSE   FULL-SCALE   DIE   DATA



          6R1D VERSUS CALENDAR THE

WE TIKE STATION 6RID

19-Sip-85 1317-1350 3.1 3.1
19-Sip-85 1107-1138 3.2 3.1
19-Stp-B5 1423-1449 3.3 3.2
19-S«p-8S 1500-1522 3.4 3.2
19-S«p-8S 1534-1557 3.5 3.3
19-SBP-85 1622-1641 3.6 3.3
19-Stp-85 1154-1218 3.7 3.4
19-Sip-85 1230-1301 3.8 3.4
M-Stp-85 0829 '3.2 3.1
M-Ssp-85 0817 3.4 3.2
JO-Stp-85 0809 3.4 3.3
20-Sjp-BS 0937 3.8 3.4
2»-S»p-85 1014 3.2 3.1
20-Sgp-BS 1023 3.4 3.2
2»3*I3W.unuuu,,n
0.2 1.90
0.2 2.18
0.2 1.4?
0-2 1.54
1.4 1.47
2.0 2.02
3.3 1.72
3.3 1.74
0.4 2.25
tO i gn
*«7 1.38
5.1 1.78
5.5 1.94
0.4 2.25
1.4 1.54
4.7 1.94
5.3 1.78
0.2 2.25
1-1 1.87
4.1 1.94
4.9 2.04
AVERA6E •

aMMwlMM^^, °IE'fJ
24 4 0,0588
26 6 0.0444
24 4 0.0422
26 4 0,0584
26 4 0.0408
26 4 0.0671
24 4 0.04J20
26 4 0.0441
26 4" 0.0570
26 6 0.0417
26 4 0.0498
24 4 0.0557
26 4 0.0711
24 4 0.0594
24 6 0.0504
26 6 0.0582
24 6 0.0490
24 4 0.0554
24 4 0.0447
24 4 0.0540

ALPHA
SOTE
mutnunn,
0.0601
0.0682
0.0434
0.0403
0.0728
0.0833
0.0944
0.0970
0.0598
0.0744
0.1040
0,1270
0.0742
0.0494
0.0949
0.1268
0.0504
0.0424
0.0804
0.1082

AVERASE
APPARENT
ALPHA
lunnuui
0.23
0.27
0.24
0.23
0.28 :
0.33
0.34
0.37 '
0.24
0.29
0.40
0.50 .
0.30
0.24
O.J8 ;
0.49
0.20
0.24
0.32
0.43
       58

-------
                                                        TABLE  17-continued
                                           lOKRflE   FUU-8CHII   (JTE   BATH

                                                     MID VERSUS CftUXItt T«
                                                *T
   -»*'"»"~~-~~~~^                                                           flT£(fi      «;       ^

    20-S.P-83    1533     3.2    3.1      0.450     21.4       0.4        2 »                  ™--"-<™»»«-~»»»»,



   20-S.P-83   1549     3 4    T j       '         '         ''*'        '^         "     '      M492,     «-.««        0.23
                      "»>    J» J      0.3oO    91 L        M m
                                      vi«v    8f         .,     .

 «•«   0825     3.8    3.4       0.339    20 0      7 3        , „                       ^   '   M9"        ^

                                              '                   1<7°        24     4       0-0317      0.11,4        0.43



                          Ifl       °'434   '  "•'       0.8        2.17         24      A       .....   :

21-S.,85   1132      ,4    ,2       0.372     1,4        ,2        1.84         2i                     ;   ^      ^

21-Si|i-85   ,201      3.4    3 3                                                              0.0430   .   0.0350       0.21


21-3tf,-85   1219     3.8    34       . w    ,.          '         *'"         "   '  *       °l0352      °'0754        0.29
                           '        ^»«>Ti    ly,j       jB7        i 07         _                      ;
                                                                           24     4       0-0402    ;  0.1017        0.40
                                                     59

-------
            TABLE     18




"ONROE, WISCONSIN   -   SAHPLWB  PLAN  EVALUATE



                   PASS  1



           ALL SRIOS BRV0 =6-
,
1

i "B' |. .A.
OFFSAS 1 ! POSITION !| Pos

STATION ! FLUX RA>E' a SOTE 1 (AVEURNALSY£S) | ,' •
======== jr
!
3.1A
Z.IC

3.2A
3.28
3.2C

3. 3A ,'
3.38 !
3.3C i
3.4A
3.48
3.4C
1 ' i MEAN WT ! !
	 | JSL ;,„?:;„ j;,:^,
0.412 ! 0.0678 !! j '',']
!:S;!'°o:!SM!0-334! ••«« j« o.-^'
! ii ,' (' •
0-453 ! 0.0540 i! I ',',
J:SI iSS!!0--"7.! o-«»3 ;; o.«7
	 ;; ' i ;,'
0-334 0.0688 !i ! "I
SiSrj.J:!!;;!!0^8! ••»>*» ••*»
• '• i • i ,'
0.310 ! 0.0615 " '. !!
0-312 ! O.OS65 "' 0 TO .' « ~* '' '
0.300 ! 0.0628 •' '• °'0565 !! °'3<>5
si1 i ::
OVERALL AVERA6E FLUX [,' 0 350 • "
PASS 1 j. 0.358 , J; 0-364

OVERALL MEAN
PASS




II , ' '
"EISHTE00TE !,' f 0.05SO f}
;; ! -ii
" !
ii ' ' i
it j i ,
ii
' '
* "C1 ,'! «j(j«t .g.

nut v i '
UNL* ! ! POSITIONS
_;___OTE i! FLUX ! QTE
! ll \l
II • ! !
i 0.0622 I! 0.379! ! 0.0604
1 !! ! j
! !l '': '
' II '
! i !
0.0699 !,' 0.424'! 0.0662
11 * I
II 'i
0.0654 !! 0.339 'I 0.0634

! ! j
0.0621 :: 0.307 ! 0.0602
: U f
U !
!! 0.362 !
ii (
i ! I
IJ ij
°'0651 || l! 0.0628
I 1 J

'* ' i
!! •
                  60

-------
              TABLE    19




MONROE, WISCONSIN  -  SAMPLtNB PLAN EVALUATION




                   PASS 2




            ALL GRIDS BRVo *  6*

STATION



3.5A
3. SB
3.5C

3.6A
3.6B
3.6C

3. 7 A
3.7B
3.7C

3.8A
3.86
3.8C

•
OFF6AS
FLUX RATE
=========


0.326
0.336
0.339

0.415
0.412
0.395

0.372
0.334
0.328

0.362
0.328
0.356

! ' "BM II "A" t 'C' II »fl« •»•
!l POSITION II POSITIONS || V-c"
'I ONLY 1! ONLY || POSITIONS
1! ! MEAN NT 1! j HEAN NT !!
—„...„;; FLUX ; OTE !l FLUX ! °TE n FLUX
'""""" ~ "* ' "•"• — — — — — a* i j3SS2 — XS,333333SS3 [ ' SSSSSS
!i i Hi - j. ;
11 1 ii I I!
0.0662 II ! M . . ,
0.0667 !! 0.336
0.0856 II
1 1
0.0852 1!
0.0785 II 0.412
0.0883 II
1!
0.0921 II
0.0943 II 0.334
0.0974 II
1 1
t 1
0.0995 1!
0.0970 I 1 0.328
0.0944 1!
i i
1!
OVERALL AVERASE FLUX i i 0.352
PASS 1 . | j
1 |
OVERALL MEAN NEISHTE0 OTE II
PASS 1 j .
11
II
1 1
TANK 3 OVERALL AVERASE FLUX !! 0.355
1!
TANK 3 OVERALL MEAN NT. OTE 1 1
1 1
! : i
0.0667 I! 0.333
1 i
1 1
1 1
i i
0.0785 i 1 0.405
1 1
I 1
1 i
0.0943 1 1 0.350
I 1
1 t
!!
1 1
II
0.0970 1! 0.359
1!
1 I
II
II 0.362
II
,0.0837 II
1!
I 1
I!
II
II 0.363
0.0707 I!
!! 1
1 is,
0.0761 i I 0.334
1 t
1 i
i 1
0.0867 II 0.407
I I

1 1
0.0946 II 0.345
1 I '
11 :
0.0970 II 0.349
II :
II
i :
i :
!! 0.359
:s ;
1 1
t i '
0.0866 II
:: i
ii , i
i MEAN NT
OTE
•XZC53X3Z


0.0729


0.0839


0.0945


0.0970




0.0871

t i |
II 0.360 1
:: i
1! 1
0.0768 I! | 0.0749
II !
!! !
                61

-------
TABLE 20

MONROE PLANT DATA OURIN8 OFFSAS TESTINB DAYS'- SEPTEMBER '83 - APRIL '86
..RAW ! SECONDAR
WASTE ! INFLUEN
09-10-85 = « = 333=!==3 = -33 = 3
FLOK (.gd) . g,, •
SvIi&EV. I'S 1! '«<> {
ISffiS" SOUDS "l/i 192 -'
33— fMNONIA <«9/l 22!! !
09-11-85 !
AVERA8EfDO'f (Sl/ij
SUSPENDED SOLIDS (•?/!
AMMONIA <»g/l)
09-19-85
B.O.D. 'g (.o/l )
AVERAGE 00 's (So/I
SUSPENDED SOLIDS (.f/1
AMMONIA («g/l)
=====3=33====-3=3S33333====as
09-20-85
B.O.D.'g (sa?l>
AVERflSE DO's io/1
SUSPENDED SOLIDS <.|/n
AMMONIA (•o/l)
=====333=3====3333=3==3=|==3=
09-21-85
FLOW (,gd)

. SUSPENDED SOLIDS (*g/l)
= = = = = = S?3 = = ?= = = = = = 3 = 3= = = |^L
12-10-85
FLOW t A \
IvifeSfeV. {;$!
SUSPENDED SOLIDS (,|/1)
,__ AMMONIA (§g/l)
12-11-85
B 0*0 '« <«9
AVERAGE DO's (So/I)
SUSPENDED SOLIDS <.|/l
AMMONIA (»o/l)
M-dS-i"**""""""""""""""
1.797 j 1.81
226 !
22.6 i
1
1.894 i 1.89
1
188 i
	 18.2 !
1
1.768 i 1.790
202 !
= __23:6 !
•
i
1-701 j 1.705
150 !
23.4 i
========{ ==3=3=3=3=3
1
1
2-096 } 2.096
1
322 !
	 12 !
i
2.209 i 2.209
530 !
5.9 !
286 !
13.9 !
zsssaasa | =3=33=3=333
i
BToT'D.'s (i!??! 2'9§2 | 2.134
A V ERASE DO * B {* /i i 420 t
SUSPENDED SOLIDS (Sg/t) 234 '
_s 	 ?!:!!5_i5_ . f«g/H 10.0 !
3========S===3== 33=3=33= ! =3=======3-
04-09-86 i
B^KD.'s f.JIfi 2>i!5 I 2.248
AVERASE D0'» (•a/I) 40 •'
AMMONIA" S°LIDS {"»'" 266 •
04-10-86 !
s'oV-, ,iMf! MM! 2.130
AVERAGE 00 'g (io/1) A S /
IMMON?AED SOLIDS j«9/i) »§ i
ftnnoNlA («g/l) 9.13 !
FINAL i PQND !
EFFLUENT ! RETURN !
= 3 = 3 = 3 = 33= j 3 = 3 = 3 = = -z {
' !
.„ ! 1.296 !
.18 ! 220 !
5.4 ! 2.1 !
. ?J ! 532 !

j 1
.„ ! 1.300 !
19 220 1
7. 0 J 570 !
{ 1
., '• 0.485 1
74 ! 260 I
4A? ! 1-1 !
,120 ! 448 !
3.66 ! 7.30 !
33AERATION

ilil
=33=3=3333.
1410
:=3 = 33=aa3«
1365
=========3| 3=3=33333 ! =3=3=3=3333
• !
• 54? ! !I! !
- ========= !==*e=B=s3 j-
i |
66 ! °'52' 1
5.5 !,. 3.0" !
IAJ 1 *r * *r 1
104 1
	 1.65 i i
• ~" i

i J
33 ! 310 !
8.9 ! 1.2 !
13 2 ' 2°8 !
= 3 = 3 = 3533! = = = = = = = = = j'a:
! {
1225
X33=====33


- 4.7
1025
I===3=3===

4.1
. 2858
======3=3=

93I •'• i33 i
3=3=33=33 [ 3333==3=S {=33333=3333
j J
2.134 !
33 ! 220 i

7 II ' *27B I


3.0

======== j ===33=3==! 3=3333= ====
1 '
2.248 ! !
94!i e3??!
38 ! 236 !
9.37 ! 6.17 !
«......,....„..,, 3=
I J
2.129 ! i
70 i 400 !
7.0 ! 0.4 !

6.6


l!380
62

-------
                       FIGURE   19
                   MONROE, WISCONSIN
                OFFGAS SAMPLING PUN - S«pf., 1985
                «rr     TANK   3
102









n





J
L
p-


3.4C


3.3C



3.2C


3.1C
4=
a ri



3. IB
GRID 2

3.38


*
3.28
GRID 1

3.18





3.4A


3.3*


&\
3.2A I


3.1A 1
-M




1 3.5A


1 3.6A
'.


3.7A


3.8A

cm ,



i ;p zcf
w. IV a.«/v
1
GRID 3

3.68 3.6C



3.78 3.7C
GRID 4

3.88 3.8C
-1— 	 '
      PRIMARY
RAS
                                            TO CIARIF1ER
                        63

-------
                h         K                 -*'•  The
             alpha  for  these efficiencies  are  0.38  and
   nk-a;  F12Ure. 2°'KWfich Plots  alpha-SOTE and alpha
 sJaLin " H on' indl"tes both  parameters  increase slightly up to
 Station 3.5 and then rise dramatically to  the  end of the tank?

      Three  tank  cross-sections  were tested  in  Tank  1  which
 employed coarse  bubble spiral-roll aeration,   two in Pass  1  and

                                                                ™
      and 5%2V Th?h °VSrali alPha-SOTE  *- the first   pass
 4.^ and 5.24  for the second pass.  During the  test, Tank  1  was
 receiving  approximately 3,8OO  scfm,  while the  fine pore  grid

 3£  data"   h^ 3 WHS g^lng  ab°Ut 2'10° Cfm- rt is ev*de"t from
 the  data  obtained   that  the  new  ceramic   grid  system   was
 ^01^   ^°re  e"iciB"t than the coarse  bubble; system be^ng
 replaced.    It  may  be  noted subsequently  in  the1  section  on
 Economics Considerations  that the magnitude of  savings  ac?ual?y
 achieved are in good agreement with the above results.

    '  One week  later the  investigators returned  to! the  site to
 Conduct  three  days of  comprehensive testing  to appraise various
 Campling plans and   to  monitor alpha at various  times during ?he
 day  for  several   days  in   succession.    This  offgas  data  is
 summarized in Table 17.                              >     u^i_a  is
                                                     i

      On  September   19th,  all   24  offgas  hood positions  shown in
 Figure  19  were  carefully sampled.   Tables 18 and  19 present the

                     these   sts   and the        '
            ad           -
         i        '  resPectlvelV-   The objective of I the sampling
      analysis was  to determine   the  fewest  number ! of  saml
positions   required  per   station   to   produce  an
                                                       .
sampling  plan indicated  in Figure   19,   using the -A" and  "C"
                tX?iC*Uy'"Md  f°r the   ™*ind«r o*   the study.
              to 21  and all  others  of the  same format, the datl
  i           a:tlculf^ station represents the average results of
all of the positions tested at that cross-section.

     Figure 21 is a plot  of alpha-SOTE and  apparent lalpha versus
tank location.  Unlike data  from September  llth,  both pa?am!tJrI
are only  slightly affected  by location   within the !  basin?  The
overall alpha  for Pass  1 i.  about O.24  and   for  Pass  2? abou?
                                                     I

     The remainder  of the data  in Table  17 deals   with trackinn
alpha with time of day and day  of the week.   Figure 22 is a plo?
  '                                    -individu.l?yf  f|or
         d                                         f
       f??   ^   i  ?'  x    1S readilV ^PParent from  the|  figure,  the
       lity of  alpha  for  the three  days in question,  ending on  a
                              64

-------
         0.20
  ALPHA   0.18
  sore
(DECIMAL) 0.16
         0.14
         0.12
         0.10
         0.08
         0.06
         0.04
         0.021
                             FIGURE   2O
                      MONROE, WISCONSIN
                   ALPHA AND ALPHA SOTE VERSUS TANK POSITION
                         TANK 3-SEPTEMBER 11,1985
                             PASS1
                                      PASS 2
 1.0
 0.9
 0.8
 0.7
 0.6
 0.5
 0.4
 0.3
 0.2
0.1
  ALPHA
   OR
APPARENT
  ALPHA
                    3.1   3.2   3.3   3.4   3.5    3.6    3.7  ;  3.8
                                SAMPLING LOCATION              \
                               65

-------
                          FIGURE   21
                     MONROE, WISCONSIN
                  ALPHA AND ALPHA SOTE VERSUS TANK POSITION
                        TANK 3 - SEPTEMBER 19,1985
                           PASS1
PASS 2
         0.20

 ALPHA   0.18
  SOTE
(DECIMAL)  0.16
                   3.1    3.2    3.3    3.4   3.5   3.6    3.7   5.8
                              SAMPLING LOCATION              i
                              66

-------
    FIGURE  22
MONROE, WISCONSIN
    ALPHA VERSUS THE




















-



0,
























6 0,


A
1





TAUtf 1
innft J,
PACf 0
"A3j /

/
/
9
\
\
\






5 0,
£
/
/

\
\
\
\
\
> 1
/
\
>






\
\
\
\
0
4 0,
APPAREN

/
/
T
I
I
\
\
\
kUV 1 M
WR J, T
A^ 1 ra
AJJ 1 w
/S
«^
V
1
1
t
1
t
I
I
1
0
3 0,
T ALPHA
67
n

CATjJ
3AIU
crpTrij
JLI III







FRI
SEPTEW






TUIID
InUn
TPTTU
JLi ILM

2 0.


nruy
KUAT
nro 91
ULK L\







)AY
8ER20






rjniY
pUAI
nrn IQ
oLK 19

1 £
I4UU

-------
Saturday, was   quite minor.  Overall,  Pass  1  alphas  varied from
O.195  to  O.28O and  averaged  approximately  O.23.   In  a similar
way, Pass  2 alphas ranged from  0.33 to  O.45  and   averaged about
O.39.                                                  \
                                                       j
     The final  two  offgas evaluations, prior  to all  three tanks
coming on  line in parallel, are   summarized in Tables; 21  and 22
and Figures  23 and  24.  Figure   23 is   particularly  interesting
since  Tank 2 had been operational  for only  15 days, while Tank 3
had  been on  line for  98 days,   and yet their oxygen  transfer
performance is  for all  practical  purposes,  identical.   This data
suggest little   if any OTE  degradation due  to  diffuser fouling.
Figure 24  show a similar  relationship in April, 19S6|,  after an
additional 12O   days of continuous operation  and essentially the
same alpha-SOTE values.                                !
                                                       i

Tank Draindowns - May. 1986                            ;

     During the second week of  May, Tank   2,  after 168  days of
operation, was  drained  for cleaning.  The following  week Tank 3
was  drained  after  25O  days  of  operation.   In  both  cases,
diffusers were  removed from each   grid shortly after draining and
prior  to  cleaning and were  returned to  the laboratory  within a
couple of hours.  Analyses  similar to those previously described
for  the  pilot diffusers   were  conducted.    The  results  are
presented in  Tables 23 to  26.  Tables   23  and 24   summarize the
BRV, DWP and clean  water steady-state oxygen  transfer! efficiency
data for the diffusers as received after  service and new.

     For both tanks, the BRV's increased  to  a  greater  extent than
did  the  DWP.   After  168 days,   the  26 specific  permeability
diffusers had   a BRV increase  of  3.14 times the initial  values,
while  the  same permeability diffusers  in Tank 3 increased  by a
multiple of 3.65 after 25O days.   In a similar way, the DWP's at
O.75 scfm per diffuser rose to  1.7O times their initial  value in
Tank 2 and 2.14 in Tank 3.                             ;

     The BRVo 4 diffusers removed  from  Tank 2  had a BRV increase
of 2.27 times and a DWP  increase  of 1.4O times; this  compares to
increases of 3.14 and 1.7O for the BRV0 6 diffusers  in  Tank 2 for
BRV and DWP respectively.                              '

     The above  data  suggest that  the diffusers with  larger pore
diameters  may  have  fouled to  a  slightly   less degree  than the
finer diffusers, and that the diffusers which had beenjin  service
longer were fouled  to a somewhat  greater extent.    In  all  cases,
the ratio of  DWP/BRV dropped significantly  from about  O.9O down
to the  O.5O range.  Based  on an  earlier discussion  of  diffuser
fouling,  one would  normally expect  a reduction  in the   oxyqen
transfer capability of these diffusers as a  result of the changes
in BRV, DWP and  the ratio of the two.                  i
                               68

-------
              TABLE  21





HONROE   FULL-SCALE   OTE   OATA



          6RIB VERSUS CALENDAR TIKE
DATE

10-BK-85
lO-Bie-85
10-DtC-85
lO-Btc-85
HI-Dtc-85
Ki-Dsc-85
ld-Bsc-85
1C-DK-8S
ll-Dtc-85
ll-Dtc-85
ll-Dtc-85
ll-DKr85
ll-Dtc-85
ll-Dtc-BS
ll--Dtc-85
ll-Dtc-85
ll-Dtc-B5
ll-Dtc-BS
TIHE

1345
1507
1529
1423
1612
1544
1457
1432-
0829-0818
0851-0907
1030-1050
1124-1137
1212-1225
1249-1300
1353
1407
1441
1454
STATIUN GRID
*"
3.1 3.1
3.2 3.1
3.3 3,2
3.4 3.2
3.5 3.3
3.6 3.3
3.7 3.4
3.8 3.4
3.1 3.1
3.2 3.1
2.1 2.1
2.2 2.1
2.3 2.2
2.4 2.2,
2.5 2.3
2.6 2.3
2.7 2.4
2.8 2.4
AVERA8E
FLUX RATE
3I-S,_,___,,
0.195
0.234
0.237
0.142
0.134
0.160
0.149
0.158
' 0.179
0.211
0.304
0.326
0.244
0.285
0.2B3
0.278
0.278
0.283
HLT
"C
SSS— 33-38.
11.6
11.6
11.6
11.6
11.6
11.6
11.6
11.6
li.5
11.5
11.1
11.1
11.1
11.1
11.1
11.1
11.1
11.1
AVERA6E
0.0.
-='——=--
0.2
0.2
0.1
0.1
0.2
0.5
0.4
0.5
0.3
0.2
3.4
3.0
0.7
0.3
4.0
4.1
5.2
S.7
AVERASE
AIRRATE
PER BIFFUSER
333333333332233!
0.98
1.17
1.19
0.71
0.67
0.80
0.75
0.79
0.90
1.06
1,52
1.63
1.32
0.00
1.42
1.39
1.39
1.42
AVERABE
SPECIFIC
PERU BRVo
i3=K35SSSaS33S=2
26 6
26 6
26 6
26 6
26 6
26 6
26 6
26 6
26 6 -
26 6
38 4
38 4
26 6
26 6
26 6
26 6
26 6
26 6
OTE(f)
=3393=33333
0.0861
0.1148
0.0836
0.0779
0.0809
0.0988
0.0899
0.0904
0/0814
0.1062
0.0536
0.0747
0.0935
0.0747
0.0576
0.0675
0.0626
0.0513
AVERABE
ALPHA
SOTE

0.0900
0.1198
0.0866
0.0807
0.0842
0.1054
0.0951
0.096B
" 0.0839
0.1143
0.0768
0,1023
0.1034
0.0794
0.0876
0,1045
0.1108
0.0975
AVERABE
APPARENT
ALPHA
.323233333
0.32
0.43
0.31
0.26
0.27
0.35
0.31
0.32
0.30
0.40
0.30
0.40
0.38
0.30
0.33
0.39
0.41
0.37
           69

-------
               TABLE   22





HONROE   FULL-SCALE   OTE    DATA



          GRID VERSUS CALENDAR TIKE
DflTE TIffi STATION BRID

OV-Apr-84 0710-0720 3.1 3.1
0?'-Apr-84 0734-0745 3.2 3.1
09-Apr-86 0803-0812 3.7 3.4
09-Apr-86 1029-1043 2.1 2.1
09-Apr-84 1131-1142 2,2 2.1
09-Apr-84 1225-1235 2.3 2.2
09-Apr-84 1308-1320 2.4 2.2
09-Apr-84 1330-1345 2.5 2.3
09-'Apr-84 1242-1248 2.4 2.3
09-Apr-84 1154-1210 2.7 2.4
09-Apr-84 1054-1112 2.8 2.4
09-Apr-84 1404-1418 3.1 3.1
09-9pr-84 1515-1528 3.2 3.1
09-*pr-84 1422-1632 3.3 3.2
09-Hpr-84 1707-1716 3.4 3,2
09-llpr-84 1724-1733 3.5 3.3
09-llpr-84 1440-1449 3.4 3.3
09-(lpr-84 1537-1548 3.7 3.4
09-{0r-84 1430-1449 3.8 3.4
FL'STE
333£:»3»3
0.200
0.251
0.201
0.232
0.225
0.219
0.171
0.130
.. 0.127.
0.124
0.142
0.188
0.195
0.180
0.172
0.213
0.203
0.200
0.193
«LT AVERA8E
=K=:===;:==^==rr===
12.0 4.8
12.0 5.0
12.0 7.2
12.0 3.4
12.0 3.0
12.0 2.5
12.0 2.5
12.0 4.6
12.0 5.2
12.0 5.7
12.0 6.2
12.0 0.7
12.0 0.7
12.0 0.8
12.0 0.7
12.0 5.4
12.0 5.6
12.0 4.4
12.0 6.4
AVERA8E
i»rai»!!![L
1.00
1.25
1.00
1.16
1.12
1.09
0.86
0.65
• 0.63
0.43
0.71
0.94
0.97
0.90
0.84
1.04
1.02
1.00
0.94
AVERAGE
SPECIFIC
_M.[^MssJ^V°
24 4
26 6
26 6
38 4
38 4
24 4
24 4
24 4
24 4 .
24 4
24 4
24 4
26 4
24 4
24 4
24 4
24 4
24 4
26 6

OTEK)
0.0540
0.0585
0.0399
0.0614
0.0680;
0,0695
0.0674
0.0584
0.0428
0.0594
0.0513
0.0813
0.0907
0.0812
0.0754
0.0489 i
0,0463
0.0469
0.0396
AVERASE
ALPHA
SOTE
0.0932
0.1029
0.1001
0.0885
0.0937
0.0917
0.0879
0.0986
• 0.1153
0.1169
0.1110
0.0897
0.1004
0.0902
0.0832
0.0941
0.0904
0.1023
0,0949
AVERAGE
APPARENT
ALPHA
0.33
0.38
0.35,
0.33
0.34
0.33
0.30
0.32
0.37
0.37
0.34
0.31
0.35
0.31
0.28
0.33
0.32
0.34
0.33
            70

-------
     FIGURE  23
 MONME, WISCONSIN
  ALPHA SOTE VERSUS TANK POSITION
TANK 2 ft 3 - DECEMBER 10 ft 11,1985
      PASS1
PASS 2
.1    .2    .5    .4    .5    .6    .7
          SAMPLING LOCATION
        71
0.20
ALPHA 0,18
SOTE
(DECIMAL) 0,16

0.14
ft
0.12
A 4 A
0.10
0.08
0.06
0.04
0.02
1.0
0.9

0.8

0.7

0.6
A £
0.5
0.4
0.3
0.2
0.1
^ 	 p*3 	 f,
1
ALPHA - 1
OR 0 TANK 2,
APPARENT D TANKS1
ALPHA |
ALPHA SOTE '
i
A
/ / \^ ^^^^^f] ^^A
V ^
\
\
I
	 1 	 1 	 1 	 l__l 	 1 	 1 	 1 	 1 	
         .8

-------
      FIGURE  24
MONROE, WISCONSIN
 ALPHA SOTE VERSUS TANK POSITION
   TANK 2 ft 3 - APRIL 9,1985

      PASS 1                 PASS 2
0.20
ALPHA 0.18
SOTE
(DECIMAL) 0.16

0,14
0.12
0.10
0.08
0.06
0.04
0.02

1.0
0.9
0.8

0.7
0.6
0.5
0.4
0.3
0.2
0.1

I
ALPHA I
OR 0 TANK2.
APPARENT D TANK 3'
ALPHA ,
ALPHA SOTE '
I
^^K^ ]^^
*F-^^^^
I
I
i
— i 	 1 	 ( 	 | I [ 	 | 	 | 	 .
.1 .2 .3 .4 .5 .6 .7 .8
        SAMPLING LOCATION
        72

-------
                                                                         o»
AFTER 168 DAYS OF OPERATION...


                      SANITAIRE CERAHIC DISC DIFFUSERS REHOVED FROH TANK 2,  NOffiOE, KISCONSIN ON HAY 12, 1936


                                                 SUHKARY OF DIFFUSER CHARACTERIZATION DATA


                                                                                              TASK STARTED ON  NOVEHBER 25, 19B5
	 	 	 f
DIFFUSER
NO.
K35-67 SERIE
K39-74-1
K39-74-2
K35-66 SERIE
K39-74-3
K39-74-4
K35-66 SERIES
K39-74-5
K39-74-6
K35-66 SERIES
K39-74-7
K39-74-8
TYPE DIFFSUER
SP. PERN
38
38
38
26
26
26
26
26
26
26
26
26
BRV0
4
4
4
6
6
6
6
6
6
6
6
6
CONDITION
HEW
A5 RCVD
AS RCVD
to
AS RCVD
AS RCVD
NEK
AS RCVD
AS RCVD
NEK
AS RCVD
AS RCVD
LOCATION
AVE. OF 4 UNIT
6RID 2.1
SRID 2.1
AVE. OF 4 UNIT
GRID 2.2
SRID 2.2
VE. OF 4 UNITS
SRJD 2.3
SRID 2.3
VE. OF 4 UNITS
SRID 2.4
BRIO 2.4
eiv
(in. «g.
4.08
10.61
7.99
5.77
15.90
19.14
5.77
20.32
18.09
5.77
17.36
C.O.V
0.034
0.137
0.076
0.036
0.261
0.281
0.036
0.107
0.127
0.036
0.073
DHP (in. »g.) :
0.50
Cfl
3.50
4.90
4.45
4.82
6.70
7.30
4.82
7.70
7.90
4.82
7.20
0.75
eft
3.70
5.50
4.90
5.08
7.75
S.80
5.08
9.00
9.25
5.08
.8.40
2.00
eft
4.20
7.55
6.25
5.96
12.15
14.60
5.96
14.25
14.45
5.96
12.45
! 3.10
cf»
4.79
13.60
'9.60
6.84
23.40
28.00
J6. 84
26.30
26.50
;6.34
21.85
! RATIO
DBP/8R
0.907
0.518
0.613
0.880
0.487
0.460
0.880
0.443
0.511
0.880
0.484
RATIO
OTE
RCVD/NEH
1.014
0.954
1.180
1.063
                                                            73

-------
ffl 240 DAYS OF OPERATION...                             TABLE    24





                  -MHTAIRE CERANIC DISC DIFFUSERS REMOVED FROH TANK 3,  HORDE, KSCONSIN ON KAY 22,






                                           SUHNARY OF DIFFUSER CHARACTERIZATION DATA




                                                                                      TANK STARTED OS SEPTEMBER 4, 1985
	 ,
DIFFUSER TYPE DIFFUSER
SP. PERM
K35-66 SERIES! 26
K40-1-1 26
K40-1-2 26

K35-66 SERIES 26
K40-1-3 26
K40-1-4 26
K40-1-4 26
K35-66 SERIE
K40-1-5
K40-1-6

K35-46 SERIES
K40-.I-7
K40-1-8





26
26
26

26
26
26




BRV0
6
6
6

6
6
6
6
6
6

6
6
6




1
-
CONDITION
NEM
AS RCVD
AS RCVD

NEK
AS RCVD
AS RCVD
AFTER H-ft-H
NEK
AS RCVD
AS RCVD

NEK
AS RCVD
AS RCVD






LOCATION
AVE. OF 4 UNI
SRID 3.1
BRIO 3.1

VE. OF 4 UNIT
SRID 3.2
BRIO 3.2
SRID 3.2
VE. OF 4 UNITS
BRIO 3.3
6RID 3.3

E. OF 4 UNITS
SRID 3.4
SfilB 3.4




'
BRV !
(in. »g.) i-C.O.V
5.77 ! 0.036
18.22 ! 0.16
j
5.77 ! 0.036
18.72 i 0.129
5.36 I 0.035
. 1
5.77 ! 0.036
27.16 ! 0.137
t
1
5.77 ! 0.036
20.87 ! 0.101
1
I
1
1
: i
OHP (in. »g.)
0.50
cfa
4.8
7.1

4.82
8.10
4.90
4.82
9.70

4.82
9.45





0.75 ! 2.00
cfl i eft
t
1
5. OB i 5.9
8.50 ! 13.65
i
r
5.08
9.95
5.40
5.08
13.05

5.08
12.20





5.96
16.30
6.90
5.96
23.80

5.96
22.00




1
3.10
eft
M
27.0
!""
1
6.84
30.90
9.75
6.84
52.30

6i84
48130
~

i

1-
RATIO
0KP/BR
0.880
0.46
~~
0.880
0.532
1.007
0.880
0.480
— —
0.880
0.585
~




RATIO
OTE
RCVD/NE
-
1.087
0.992
1.088
-
1.009
~
1.046



/
                                                    74

-------
      The clean  water steady-state   OTE tests  on   these diffusers
 versus new dif-Fusers of the same batch  indicate no degradation  in
 oxygen transfer performance.   In  fact,  the OTE results presented
 in Tables  23 and  24 indicate the   field  diffusers  as initially
 received, generally have QTE's which are slightly  better than the
 new- diffusers, as indicated by the ratios  of OTE as received to a
 new diffuser of  greater than one.   Examination  of the diffusers
 in an  aquarium showed  a very uniform   release of  small bubbles
 across the diffusers through the relatively thin foulant layer.

      The data  in Tables 23  and 24  indicate the   fouling between
 September, 1985, and May, 1986, was  uniform thoughout ; the tank.
                                                       i
      The foulant .tests presented in  Table  25 reveal the material
 to  be largely  non-volatile  (75%) , approximately  one third   of
 which residue  was acid soluble.   Energy  Dispersive Spectroscopy
 analysis shown in  Table 26 indicate the  the principal  elemental
 composition   of  the   non-volatile  portion   to  be   silicon
 approximately  1O7.;   calcium  approximately  47.;    iron  27.;  and
 aluminum and phosphorous approximately 17. each, as  the' respective
 elements.                                              j


 Full -Scale Performance Tests - June.  1986.  to November.  19B7

      By June 6,  1986,  final   installation of all  the diffusers in
 the   plant   was  accomplished,  and  all   diffusers  previously
 installed  in Tanks  2  and  3  had been  cleaned,  thus all diffusers
 were  in   acceptable   condition    to  initiate   the ! full-scale
 comparative performance  evaluation  involving  the  26 
-------
                            TABLE
25
MONROE DIFFUSER FOULANT ANALYSIS i
' i
* !
DIFFUSER
(1)
K39-74-1
K39-74-3
K39-74-5
K39-74-7
OVERALL
AVERAGE
K40-1-1
K40-1-3
K40-1-5
K40-1-7
OVERALL
AVERAGE

TANK
2
2
2
2

3
3
3
3

i
GRID
2.1
2.2
2.3
2.4

3.1
3.2
3.3
3.4


X
VOLATILE
18.8
19.1
39.1
26.6
25.9
22.5
22.7
20.3
16.1
20.4

NON-VOLATILE
81.2
80.9
60.9
73.4
74.1
77.5
77.3
79.7
83.9
79.6

X
NON-VOLATILE
ACID SOLUBLE
25.2
22.3
20.7
27.4
23.9
56.5
57.3
54.0
59.7
22.7
!
ii X
NON-VOLATILE,
ACID INSOLUBLE
i
i 50.6
i 58.6
40.2
i
! 46.0
1
i
48.9
I
i
i
i
i
!
i
i
l
1 56.9
i
i
i
1

-------
                      TABLE   26

       NON-VOLATILE RESIDUES FROM MONROE DIFFUSERS

                       EDS RESULTS
                        (1)
ELEMENT
==========
Hg
Al
Si
P
S
Cl
K
Ca
Ti
Cr
Mn
Fe
Ni
Cu
Zn
Mb
K39-74-1
TANK 2
INLET
X
0.7
1.2
7.3
1.5
0/4
—
0.6
4.1
0.2
—
—
1.7
0.1
—
—
0.4
!
K40-1-1
! TANK 3
INLET
X
0.6
1.3
12.3
1.1
0.2
'
0.5
4.1
0.3

—
2.1
0.1
0.3
0.3
!
K40-1-7
TANK 3
OUTLET
X
0.5
1.5
8.6
0.8
0.1
—
0.6
3.0
0.3
—
_-
1.9
—
—
0.2
"
(1)   This  Diffuser  (K39-74-1)  BRV0 = 4",  Specific Perm
     All others BRVo =  6",  Specific Pera  = 26
                           77
= 38

-------
                             TABLE   27





MONROE PLANT  DATA DURING OFFBAS TESTINS DAYS - JUNE '86 - NOVEMBER  '-'t
07-08-86
FLOW , (agd)
B.O.D.'s (•a/1)
AVERASE DO's (ml/I)
SUSPENDED SOLIDS 
AMMONIA (»g/l)
========3333=3333=33=3=3=3333
07-09-86
FLOW 
-------
                     TABLE  27 - Continued                \
                                                             i
HONROE  PLANT DATA DURIN8 OFFSAS TESTINB DAYS -  JUNE  '86 - NOVEMBER  -87
08-17-87
FLOW (igd)

|I||Eg°S§LIDS {jj'jjj
=====================3=*l=i-_
08-18-87

B.O.D.'s (ajfj!
	 @8ffi;}3iM i-J/jj
08-19-87
FLOW (agd)
AVERA8EBDO's (•a/1)
CIICDf hinpn AMI «« \t*\4/ 1 1
wU3rCNvCu SOLIDS ( (ft O / I )
AVERA6ESDO-s (S|/|j
AMMONI'A^^ SD^IDS (»g/i)
=====s==================!-==-
11-04-87
FLOW (agd)

lMMON?fiE" SOLIDS (ag/1)
============================= j .

RAW
=_WASTE

2.434
620
206
12.0
====s==s


2.938
400
316
10.9
=====3=3


2.546
360
186
10.7
2.312
450
394
___15.8


2.091
570
104
	 17.0

SECONDARY
INFLUENT
=====esasss

2.727
===========


3.210
S3S S33JHSSC3


2.853

2.607
300
162
	 30.9
.-========- ;

2.463
318
114
	 30.4
— ,_
FINAL
EFFLUENT
====3===s=

2.418
17
0.142


2.924
2 3
	 3=
-------
                                FIGURE  2S
                       MONROE FULL-5CALE OTE DATA








u
5
in
\







ft 51 OKIOS 1 VERSUS TOE
0.23
0.22
0.21
0.20
0.19
0.18 -
0.17 -
0.16 -
0.15 -
O.U -
0.1S -
0.12 -
0.11 -
0.10 -
0.09 -
0.08 -
0.07 -
0.06 -

O.OS -
0.04 4
!

|


i
AUO 17-19 !
,* •
/\ ]
/ \ i
MAY 5-7 // \\ ',
JOL 8-9 NOV 20-21^--^^^- — 	 ' §/ t^V 3
	 	 8' * i \}P
: x


07/07X86 01/23/*7 ». .' i
          a  GRID 1.1
        tg«v. 3 - gp PERU so>
  X  GRID 3.1

. » - gp rcnn 26)
                               FIGURE  26
                      MONROE FULL-SCALE OTE DATA
                              GRIDS 2 VERSUS TOE
a
                            80

-------
 ^
i
in
I
                                           27
                        MONROE FULL-SCALE OTE DATA
                                GRIDS 3 VERSUS TME
                            «LL UNITS MY. » - BP I-ERR
                                FIGURE   28
                      MONROE FULL-SCALE OTE DATA
                               GRIDS * VERSUS TIME
                           AH. UNIT* BSV. t - V KM 34
                             81

-------
  0.90
  0.80
  0.70
  0.60  -
  0.30 -
  0.40 -
  0.30 -
 0.20
                                 FIGURE  29
                       MONROE: FULL-SCALE OTE DATA
                            ALPHAS OF GRIDS 1 VERSUS TIME
   07/07/86

       D  GRID 1.1
     IBKV. 3 - 8P PMH 001
   01/23/87

        CALENDAR TIME
   *   GRID 2.1
OP.V. 4 - BP PMH 30)
        08/11/87
   X  GRID 3.1
(»«v. 6 - BP pern*
 0.90
 0.80
 0.70 -
 0.60 -
0.50 -
                                FIGURE  30
                     MONROE FULL-SCALE OTE DATA
                           ALPHAS OF GRIDS 2 VERSUS TIME
0.40  -
0.30  -
0.20
                               82

-------
   0.90
   0.80
   0.70
   0.80
  0.90
  0.40
  0.30
  0.20
    07X07X86
                                 FIGURE  31
                       MONROE FULL-SCALE OTE DATA
                            A">"*S OF GRIDS 3 VERSUS TIME
       0  GRID 1.3
 0.90
 0.80
 0.70
 0.60 -
 0.90
0.40  -
0.30 -
0.20 -
          FIGURE  32
MONROE FULL-SCALE OTE DATA
    _W£HAS Of GRIDS 4 VERSOS TIME
                          •LL IMtT« WV. i - n. ,.
                            83

-------
 -.1.  Oxygen transfer data -For Grids  2, 3 and 4, (Figures 26, 27
 and 28)  all  employing BRV0 6 diffusers,  show similar variations
 in alpha-SOTE among Tanks 1, 2 and 3 as those shown in Figure 25,
 and the  order of  highest  to lowest alpha-SOTE is  variable from
 grid to grid.  In  light of  the above observation, it;is unlikely
 that there  is a  significant statistical  difference  between the
 tsKVo 6,  4, and 3 diff users on May 5-7,  1987.          !

      In August, 1987,  an offgas survey was  conducted similar to
 the others.  The  August data stands out in Figures  25-32 due to
 the high alpha-SOTE and high apparent alphas when compared to the
 other tests.    During the  August test,   the plant  was returning
 some return activated sludge to the equalization pond^nd gettinq
 a  significant BOD   reduction across  the equalization1  pond which
 was being  used in-line.   Table 27  indicates significantly lower
 influent BOD  concentrations to  aeration (approximately 21O mg/1)
 as compared to the other  offgas evaluations (BODs 27O-56O mg/1>
 Apparently, primary  effluent BODs of  about  4OO mg/1   were being
 reduced  to the  low 2OO mg/1  range in the   pond, thereby reducing
 the loading to the aeration   tanks.   It  is  considered  likely that
 the reduced BOD loading to  the aeration tanks may be  responsible
 for the  relatively high OTE's during the August  evaluation.

      Considering the  variability of all the   alpha-SOTE data and
 ^f^rsnces  In rank   at the   various sampling  times In  Figures
 -c.5 ^S,   it  appears  that the   apparent differences  in  alpha-SOTE
 indicted  in Figure  25  are not  statistically significant
OTE Versus Flux Rate                                  j

     On three  occasions between  July, 1986, to  November,  1987
the  applied airflow  rate to  one or  more grids  was varied   to
observe the relationship of OTE versus airflow per diffuser  under
process conditions.  These data are plotted as Figures 33, 34 and
-5  for  July 9,  1986,  May,  7,  1987,  and November  4,   1987,
respectively.  The  clean water shop  test data are  also plotted
over a  range of  air flows  for comparative  purposes.  Although
there  is some  variablity in  the data,  in general, ! higher air
rates result in lower alpha-SOTE values similar to the results  of
the new diffusers tests in clean water.
                                                    that
     It is also of interest to  consider the effect
has  upon alpha,  since it  has an  important influence
appropriate selection  of diffuser  flux at design
effect may be  gauged by the difference, if any,  in s
log alpha  SOTE versus log  flux in  clean and in
The plots of Figures 33 through  35 give indication' of
any,,  difference and  consequently little,  if any,
flux  upon  alpha.   This  finding   is  at  variance
literature references.
                              84
    air rate
    upon the
         The
  ope of the
  ess water.
  little, if
influence of
  wi th  some
                                                    loading.
                                                   process

-------
                                      33
ALPHA
 SOTE
                             JULY 9,1986                         I
                                                                i

                        X   3BRV0   50 SP PERM   TANK 1   GRID 1.1
                        0   6BR\fe   26 SP PERM   TANK 1   GRID 1.2
                        Q   4BR%   38 SP PERM   TANK 2   GRID 2.1
                        A   6BRVb   26 SP PERM   TANK 2   GRID 2.2
                        0.20    0.300.40    0.600.801.00    1.50
                                    RATE (SCFM/FT2)
                                85

-------
               FIGURE  34
           MONROE, WISCONSIN
               MAY 7, 1987
0.50
0.25
0.20
0.15
ALPHA 0.10
SOTE 0-09
0.08
0,07
0.06
0.05
0.04
0.03
X
0
0
A



«
^
B-_J^





3 Bl% 50 SP PERM TANK1 GRID 1.1 1
6BR\(> 26 SP PERM TANK 1 GRID 1.2
4BR^ 38 SP PERM TANK 2 GRID 2.1;
6BR\fe 26 SP PERM TANK 2 GRID 2.2 1
^— ^



:=a-^=ft

^--^




4LE



-A
^
D^
~tr"



N WATER






\



NEW
* —































i

i
i


i
i
,
:
i
0.10
0.20   0.300.40    0.600.601.00
       FLUX RATE (SCFM/FT2)
1.50
                  86

-------
                FIGURE  35
          MONROE, WISCONSIN
0.10
             NOVEMBER 4,1987                    j

           X  3 81%   50 SP PERM   TANK 1  GRID 1.1
           0  6BRH,   26 SP PERM   TANK 1  GRID 1.2
           D  4BR\b   38 SP PERM   TANK 2  GRID 2.1
           A  6BR\b   26 SP PERM   TANK 2  GRID 2.2
U.JU
0.25
0.20
0.15
ALPHA 0.10
SOTE M9
0.08
0.07
0.06
0.05
0.04
fl(K
— • — .










— -^



V
Affr-





-CL£




	





N WATER
~--^




r==~tf 	
^




NEW
—































I

i
i
!




.
i
!
0.20   0.500.40    0.600.801.00   1.50
            RATE (SCFM/FT2)
                   87

-------
      The data  shown in Figures  33-35 are further  evidence that
 diffuser -fouling did  not have a pronounced effect  on the oxygen
 transfer performance  of the system.  Allbaugh   (13) has reported
 in one  study that the  slope of  the alpha-SOTE versus  air rate
 curve  can become  steeper  (a  greater negative  slope) when  the
 diffusers are  fouled than when they  are new.  This was  not the
 case at Monroe.


 Tank  Draindown and Diffuser Cleanabilitv - June. 1988:
                                                      !
      Although the  project plan  called for the  last!data  to be
 taken in  November of 1987, Environment  Canada, contemplating an
 on-going  fouling  investigation  at   Monroe,  offered  to  make
 available to the study the data which was gathered at a draindown
 of  the three  tanks during June of 1988.   Time  elapsed since the
 prior draindown was approximately 25 months or about 76O days.

      Tank.1, the first to  be drained, contained BRV0 3 diffusers
 in  Grid 1 of  the 1st Pass and all the remaining  grids in Pass 1
 and Pass 2. contained BRV0 6 diffusers.

      Adjacent diffusers  in Brid 1, Pass  1, and GridJ2,  Pass 1,
 were  sampled  for a direct  comparison of the effects  of fouling
 upon  the two permeabilities 
-------
                  TABLE    28
                       TANK   1
HONROE   -   DIFFUSERS AFTER APPROXINATELY 24 HflNTHS KMTIflK

       SUHHARY OF DIFFUSER CHARACTERIZATION DATA

!
DiFFliSER
NO.
PASS 1, SRID
K52-21-2
1(52-21-2
152-21 -4
K52-21-4
K52-21-5
K52-21-5
K52-21-6
PASS 1, SRID
K52-21-7
K52-21-7
K52-21-B
K52-21-8
K52-21-11
K52-21-11
K52-21-12
ASS 2, SRID
KS2-21-13
K52-21-13
K52-21-16
ASS 2. GRID
K52-21-17
K52-21-17
K52-21-20
SS 1, BRID
K52-21-21
K52-21-22
SS 1, SRID 2
K52-21-23
K52-21-24
SS 2. SRID 1
K52:21-25
K52-21-24
SS 2, BRID 2
K52-21-27
TYPE DIFFUSES !
SP. PER
50
50
50
50
50
50
50
26
24
26
26
26
26
2u
26
26
26
26
26
26
50
50
26
26
26
26
26
	 i LuiwinuN
i
8RV0 !
1
3 ! AS RCVD
3 ! HOSED
I
3 ! AS RCVD
3 IflFTER H-8L-
3 ! AS RCVD
3 ! AFTER H-ft-
3 ! AS RCVD
6 ! AS RCVD
6 ! HOSED
6 ! AS RCVD
6 ! AFTER H-BL-H
1
6 ! AS RCVD
6 ! AFTER H-A-H
6 ! AS RCVO
6 ! AS RCVO
6 ! HOSED
6 ! AS RCVD
6 i AS RCVD
6 i HGSED
I
6 ! AS RCVD
3 ! FIELD CLEANED
3 ! FIELD CLEANED
t
6 '.FIELD CLEANED
6 IFIELD CLEANED
6 IFIELD CLEANED
6 IFIELD CLEANED
6 i FIELD CLEANED
TINE IN
SERVICE
24 ItOS
24 DOS
24 HOS
24 HOS
24 HQS
24 HOS
24 NOS
24 .105
24 DOS
24 HOS
24 HOS
24 NOS
24 HOS
24 NOS
24 NOS
24 HOS
24 NOS
24 HOS
24 HOS
24 HDS
24 HOS
24 HOS
24 HQS
24 HOS
24 NOS
24 HOS
24 HOS
i i DSP (in. «a.) ! RATIO
BRV 1 { 	 i
(in. sg.) i C.O.V. I 0.75 ! 2.00 I DHP/BRV
! 1 cf« 1 cfa i
1 lij
11.06 1 0.216 1 6.25 ! 11.90 I 0.565
3.15 1 0.075 i 5.20 i 7.85 ! 1.651
9.58 1 0.158 1 5.35 ! 8,35 i 0.558
2.75 1 0.074 i 4,15 i 5.80 1 1.407
1 ! 1 I
13.66 { 0.273 1 7.20 ! 14.55 ! 0.527
2.36 ! 0.072 1 3.10 1 3.85 1 1.084
" ! " ! 7.35 ! 13.30 I
1 ' ' 1
16.36 1 0.217 1 7.85 1 13.35 1 0.4BO
7.83 i 0.093 i 7.80 i 10.50 1 0.996
18.05 i 0.276 1 9.35 i 17.75 1 0.518
7.33 1 0.054 1 7.45 1 9.80 1 1.016
13.00 i . 0.111 1 7.85 1 12.05 1 0.604
6.55 1 0.077 ! 6.60 i 8.70 i 1.008
" '• ~ 1 7.95 1 11.35 !
1 ' t i
14.23 1 0.139 1 7.55 1 11.55 ! 0.531
7.00 I 0.079 1 6.90 ! 9.40 1 0.986
1 '1 1
- i - i 7.30 i 10.40 1
' * ' 1 i
17.00 1 0.100 i 7.85 1 13.35 1 0.462
4-75 I 0.102 1 7.65 ! 11.30 1 1.133
! 'it
- ! ~ ! 8.10 ! 12.70 1
4.37 1 0.118 1 4.90 ! 7.40 i 1.121
2.77 ! 0.030 1 2.60 1 3.15 1 0.939
1 ! I 1
10.12 1 . 0.094 1 7.20 i 9.60 1 0.711
10.40 1 0.111 I 7.80 i 10.90 ! 0.750
' ' 1 !
7.21 I 0.127 ! 8.10 I 12.25 I 1.123
! Ill
7.56 i 0.119 1 6.95 i 9.70 I 0.919
! ! i I
8.76 1 0.134 I 7.90 I 11.40 i 0.902
EFR ! SOTE i
! S 1 CFN !
1.245 ! 0.1710 I
1.243 1 0.1684 1
1 1
1.380 1 0.1608 !
1.374 1 0.1626 i
1.109 1 0.1553 !
i.«5 1 0.1631 {
1.072 i -- j
1.382 1 0.1782 i
1-172 1 0.1973 1
. 'Mil ! . 0.1794 i
K338 1 0.1873 1 '
] i
1.433 1 0.1883 I
1.168 1 0.2050 i
1.281 1 - !
1 | ,
1.053 1 0.1766 1
1.216 1 0.1842 1
1.072 i - !
1 ,
1.091 I 0.1506 1
1.266 I 0.2088 i
I i
1.078 i 0.1078 !
1,280.1 0.1923 1
1.049 1 - J
; |
1.259 1 0.1809 1
1.446 i ~ i
2.133 1 0.1932 1
1.582 1 - i
J 1
1.075 1 0.1989 i
                   89

-------
                  TABLE   29

                    TANKS 2 J 3
KONROE   -   DIFFUSERS AFTER APPROXIMATELY 24 MONTHS AERATION

      SUMMARY OF DIFFUSER CHARACTERIZATION DATA
" ** 	 	 — - — — 	 — — 	 „ — 	 	 „ 	
1
DIFFUSER i TYPE DIFFUSER
HO ' 	
i
! SP. PE
PASS 1,'SRID 21
K52-51-1 i 26
1
K52-51-2 ! 26
ASS 2, GRID 1!
K52-51-3 ! 26
K52-51-4 ! 26
ASS 1, 6RID 1!
K52-51-5 ! 38
1
K52-51-6 i 38
ASS 1, SRfD 1!
K52-51-7 ! 33
K52-51-8 ! 38
I
j
NK 3 !
SS 1, BRID 1!
K52-72-2 i 26
K52-72-3 ! 26
SS 1, SRID 2!
K52-72-4 ! 26
K52-72-5 ! 26
SS 2, 6RID 21
K52-72-6 ! 26
K52-72-7 ! 26
[
.
1
1
I
1
1
1
1
1
!
i
•
BRV

6
6
6
6
4
4
4
4



6
6
6
i
6
6













CONDITIO

AS RCVB
AS RCVB
AS RCVB
AS RCVD
AS RCVB
AS RCVB
AS RCVB
AS RCVD



AS RCVD
AS RCVD
AS RCVD
AS RCVD
AS RCVD
AS RCVD














TIKE IN
SERVICE

24 KOS
24 KOS
24 KOS
24 KOS
24 KCS
24 KOS
24 KOS
. 24 KOS



24 KOS
24 KOS
24 KOS
24 HOS
24 KOS
24 KOS














BRV
(in. MI

-
-
-
-
-
—
--
r-



22.22
24.58
37.44
22.35
•14.12
15.05














C.D.V

-
-
-
-
-
-
-
-

.-

0.276
0.195
0.386
0.207
0.179
0.152














CUP (in. Kg. I ! RATI
0.75 ! 2.00 ! DIIP/I
cfi i cfi ! i
1 ,
8.90 ! 15.90 i -
11.25 ! 23.70 !
I i
12.50 ! 29.60 ! -
12.30 ! 26.80 ! .. -r
• 10.20 ! 23.40 i 4
11.50 ! 31.15 i -
5.70 ! 9.00 ! ~i
i ' '
6.55 i 10.40 ! • -i
i I i
j j
i : |
10.55 ! 19.15 ! 0.475
12.35 ! 25.20 ! 0.502
16.90 ! 48.60 ! 0.45]
12.55 i 26.10 i 0.562
j I
fl.65 ! 13.80 ! 0.613
3-80 1 13.90 ! 0.535
1 . *
i { ;
1 !
I { |
i : ;
! ! ,
i ' '
i ' '
i ! ;
i ' '
j r
: :' i
! { !
EFR ! SOTE
i « 1 CF
!
1
1.403 ! 0.1893
1.329 ! 0.1916
1.341 !
I
1.456 !
1.202 !
1.041 i 0.182
2.036 !
1.345 ! 0.169
1
1
j
1
2.283 i
1.408 ! 0.1733
t
1.105 i 0.1972
1.154 {'
1.125 !
1
1.185 i 0.1969
I
I
I
;
. [
i
i
j
t
,
i
•
t
i i ;. ,
               90

-------
                      FIGURE  36
                   mm, W/SCOWS/N
                6BRV(0)  -  26 SP PERM UNITS
   OR
   DWP
i °TE  v
(DECIMAL)
        0.100
A CUMULATIVE
D QUARTERLY
                       4.5      8.6        12.0
                               TttiE  (MONTHS)
  16.0    24.0
         GRID
       DiPSER
                            91

-------
                         FIGURE   37
  m
(DECIMAL)
         0.125

         0.100
                              , WISCONSIN
                        -  38 SP PERM UNITS
                                                    A CUMULATIVE
                                                    D QUARTERLY
                                 8.0 ,      110
                                TIME (MONTHS)
16.0    24.0
       GRID
     WFFUSER
                                92

-------
                         FIGURE  38
                    MONflOf , WISCONSIN
   DWP
          30

          25

          20


          15
  10
  9
  8
  7
  6

  5
  OTE
(DECIMAL)
0.200
0,175
0.150

0.125

0.100
3 BRV(0) - 50 SP PERM UNITS A CUMULATIVE
D QUARTERLY




/
/
BRY/
/
/

I?









I
\
\
\
\

i
h_- —




^•*»^_
"**»*,






f
/
/ ^
f
j
^

OTE

	 	 ~^






\
j_\^V
\ i
\
^



K
"N^
N




/
/
/
i /
/ /
/
/


/
/

                       4.5      8.0  ,      12.0
                               M  (MONTHS)
                                            16.0    24.0
                                                   GRID
                                                 DIFFUSER
                              93

-------
     The values of DWP, BRV,  and   OTE of  these grid diffusers are
shown on Figures 36, 37 and 38.                       j

     The  cleaning data  further  confirmed   the earlier  findings
with  the  pilot diffusers  that   the  Milwaukee Cleaning  Method
provided  substantial restoration  to near   new condition  of all
permeabilities    under investigation.    This  conclusion
appeared to  be applicable to grid diffusers as well;  as pilots,
and the pertinent service period  was extended to 2 years.  It was
also evident from this later   work that field cleaning  and single
laboratory 6O psi hosing provided acceptable results, i

     Although  no effort  was made to directly correlate  pilot
diffusers  with  diffusers  removed from  the  full-scale  system
obtained during  a tank  draindown, diffuser  data from  the May,
1986,  and June,  1988,  draindown compare   favorably with  those
removed from  the pilot headers.    The nature of the foulant, as
well  as  dry  weight  of   foulant  per  unit   area were  quite
comparable.  DWP,  BRV and OTE characteristics  between the pilot
diffusers and those removed from   the full—scale system were also
similar.  As a result, the use of pilot  diffusers as ^employed at
Monroe, which are readily removed  without draining the tank, can
be  an effective  means of  reliably quantifying  theinature  and
extent of fouling  and its impact on  oxygen transfer |performance
through the  use of ex  situ  testing procedures similar  to those
employed  in  this study.   Data   of  this   type  can ,be  and  is
effectively  used  <6> to  assist  in  identifying when  diffuser
maintenance procedures should  be  initiated.           j
                                                      i
Cleaning Costs                                        !
                                                      I
     The plant superintendent, Gerald Ellefson,  did assemble data
relative  to  the  cost  of the   cleaning procedure used.    The
facilities  of the  plant were not well  suited to  carrying out
diffuser maintenance.   Special portable  pumps were 'required to
drain  the  tanks  and  their  procurement,   setup  and   operation
required labor  and cost that  would not  be required 'in  a plant
where convenient  facilities were provided for   tank drainage and
diffuser hosing.                                      :

     Under  these  extenuating  circumstances,   he  computed  the
annual cost per diffuser to  be approximately *O.6O per diffuser.
However, with  the proper  equipment he   estimated the   costs per
tank of performing the Milwaukee  Method to be:        1
                               94

-------
      Function
      Hose
      Acid Application
      Hose
      Cost  of  Acid
        2,TOO Cost Per Diffuser
                          Man Hrs
15
12
IS
                                           Cost at
ISO
144
216
                54O
                 23
Cost at
*2O/hr

 300
 24O
 360

 900
  23
                                           *O.2OS
                                                          *0.342
     The additional  cost  to drain and refill the tanklunder these
circumstances  was not estimated, but  is considered to be nominal
at best.  The  $12 per hour  figure for labor was used since it was
the  prevailing  cost  in  Monroe,  Wisconsin.  The  *2O figure  is
considered to  be more realistic in urban areas.       ;

     Following  the  formal   completion of  the study,  the Monroe
sta-i-f concluded  the  optimum diffuser  cleaning cycle to be within
the range of 12-1S months.                             !     *"nin

Economic Considerations
                       —                                I

     The operating costs  and time to return the investment on the
capital equipment  were not rigorously evaluated.    However, Mr
 i  fT did SDmE  analvsis  erf   the operating data,  the results of
which do shed  light  on the  economic consequences of the retrofit
 If  S ^Sr  °f sufafnittal  erf  the 1986 Annual Operating  Report is
attached as Appendix  II.                               !  "^HW t is
^   xK impact °n ae^ation power costs  is  discussed  in  Paragraph
5e of that report which follows.                       i

      "e.  Our electrical power use  dropped by  over  216O  KWH per
       ^-.uDr  ab°Ut  *10°  per  day sav*™3 even   with  all   the
      additional  equipment   on  line.   This   is    due  to   the
      installation of fine air diff users in all three (3)  of the
      aeration  tanks.  In  fact the  amount of  electrical power
      used for BOD reduction in our aeration tanks  has! dropped by
      ?KBr^45 Percent  due to  that new equipment installation.
      The blowers  used for  BOD reduction  account foj-  about 7O
      percent  of all  electrical power  purchased monthly.    The
      additional  cost spent  during  construction  for  Fine   Air
      Diffusion Equipment will have a  very rapid pay  back on our
      investment. "                                     !
                              95

-------
      It  is  evident   that the retrofit was very  successful  from a
process   as well  as economic  standpoint.  It is also interestTnS
to note  the agreement  of these power savings with those  predicted
previously  in  this   report based on full-scale  offgas tests   It
is also  pertinent that the operating efficiency over  the two year
period has   been  maintained,  and diffuser  cleaning  requirements
have  been,   modest,  and  the  prospect  of   continued  favorable
experience  in  these regards is very good.  It is also I evident the
results   would have been  similarly favorable  had the   retrofit
employed any  of  the  four  pore size  diffusers involved  in the
study, although the optimum is  estimated to lie within  the broad
range of  BRV0  from  4 to 7 inches water.               j

oo   ^oi5  °*  interest to note»   however, that the data  of  Tables
*K an2J?   reveal the  diffusers  in   cleanwater efficiency between
the  BRV0 4 and BRV0   6  in Pass  1   locations to be about  47
favoring  the  BRV0  6,   in  both the  "as received"  I and   "after
cleaning" conditions.    This difference  is  estimated  to be near
and perhaps beyond the capability of  the  test  methods  employed to
quantitatively differentiate.  On the other  hand,  it may be shown
using the   procedures  outlined in  Chapter 7,  Design   Manual Fine
Pore Aeration System,  EPA/625/1-89/OXX, September, 1989,  that the
power  savings of  even  such  a  small   increase  in  efficiency as
indicated can be  significant relative to the  first  cost of fine
pore diffuser elements.                               I
                             96

-------
5.
                            CONCLUSIONS
 The  range   of  optimum effective  pore size o-f   rigid  porous
 diffusers   from  the  standpoints of  transfer  efficiency
 backpressure   and  facility of  cleaning  was   found  to   be
 surprisingly   broad.    Expressed  in   terms  of  BRV0    it
 appeared to fall  within the range of 4-7,  which,encompasses
 most,  if not all,  of  the common commercial  products sold  in
 the  U.S.

 Operating   parameters   and  wastewater   characteristics
 especially  loading,  appeared to have a greater influence  on
 alpha-SOTE  and apparent alpha than  did diffuser  pore size
 before or after service exposure.               i
                                                |
 The  cleaning procedures used  during the study,  involving a
 combination of high pressure water spraying with or without
 liquid   acid   treatment   and/or  brushing,    followed  by
 additional   spraying,    resulted     in  nearly  complete
 restoration of  the diffuser's original  characteristics.
 Consequently,  one  or  a combination  of   these  procedures  is
 considered  an  effective diffuser cleaning technique at this
 plant.   There was no  evidence   of  a difference in  the
 cleaning procedure required or its frequency over  the ranae
 of pore sizes  explored.                         ;

 Exposure to service conditions for  an  additional  20 months
 resulted  in   but  minor  changes  in DWP,  BRV,   and  OTE
 indicating  the  fouling  phenomenon   at   Monroe  was  not
 progressive.

Clean Water  OTE and OTR  of  new ceramic diff users  are not
   nSS1^ ?ffef*ed bV P0*^ size (as measured by permeability
or BKVo)  in  the ranges explored in  the study.    That is to
say,  differences  in BRV0 from 3-9  resulted in differences
not more than about 77. in OTE and  OTR.
      In the Monroe  plant, the pilot study
      SOTE  was relatively  insensitive to
      terms of BRV or it's ratio to DWP. In
      of the test, the most aggressive from
      an increase of 15O% in BRV and 4OX in
      1OX change in SOTE.
                                       gave indication that
                                      fouling expressed  in
                                      the first four months
                                      a fouling standpoint *
                                      DWP resulted in but a
                              97

-------
7.    Since full-scale DTE remained  relatively constant at about
      9O% of  its original  value, the  opportunity to  gauge the
      correlatioYi between OTE, and BRV,  DWP, or the :ratio of one
      to the other was impaired.                     •

8.    Dn the  basis of full-scale  testing, alpha appeared  to be
      constant over a wide range of diffuser flux rates.

9.    The   adverse   effects   of  fouling   with   respect   to
      backpressure,    transfer   efficiency,    and   offsetting
      maintenance costs were found  to be substantially less than
      might have been predicted on the basis of prior literature.

1C.   The  fouling tendency  and its  effect upon  the pilot  and
      plant diffusers was found to be more or less equivalent.

11.   A number of  deficiencies are inherent in  the permeability
      test when employed as  a means of characterizing diffusers.
      Other,  more  specific  methods  should  be  evaluated  and
      considered in its  place, such as BRV0  and its coefficient
      of variation.                                  i

12.   Replicate clean  water tests  conducted in  accordance with
      the  standard   ASCE  method  demonstrated   a; variability
      apparently   dependent   upon    total   dissolved   solids
      concentration.  Empirical modeling of  the data brought the
      precision of the test within the limits required to measure
      the small  differences in transfer efficiency  essential in
      this study.

13.   The  use of  various  test procedures  including BRV,  DWP,
      full-scale offgas under process conditions, and clean water
      steady—state and  also removable pilot diffusers  proved to
      be valuable adjuncts in an  investigation of this type.  As
      a matter of  interest, many of the  above conclusions would
      not   have  been   practically  obtainable   without  these
      procedures.                -•-....-.....         • •; •

14.   This retrofit proved itself to be very successful from both
      an operating and economic standpoint.          |
                            98

-------
                             REFERENCES               j
                                                      !
 1.     Ewing Report to Milwaukee MSD (1983).          j

 2.     Anderson,  N.  E. ,  "Tests and  Studies on Air  D|if-fusers  for
       Activated  Sludge," Sewage and Industrial Wastes!, 22,  4,  461
       * X ^f^J\J f m

 3.     Roe,  F.  C. ,  "The Installation and Servicing of Air Diffuser
       Mediums,"  Water Horks and Sewerage, 81, 115,  (1934).

 4.     King,  H.   R.,  "Tests to Determine  Oxygen Absorption  Ratinq
       of  Porous  Plate   Air Diffusers,"  Sewage  and  Industrial
       Wastes,  Vol.  24,  No.   8 (1952).

 5.     Beck,  A.   J., "Diffuser  Plate Studies," Senage  Uorks  and
       Journal, 8,  22 (1936).                          i

 6.     Marx,  J. J., et al.,  "Full  Scale Comparison of Ceramic Disc
       and    Flexible  Membrane   Tube  Diffusers."   &Oth   Annual
       Conference,  Hater   Pollution Control  Federation,  October
       (1987).
                                             •         !

 7.     EPA  625/3-85-010  -   "Summary Report  - Fine  Pore Aeration
       Systems." U.S.   EPA  Tech.   Trans.   (1985).

 8.     Redmon,  D.    T.,  et   al. ,   "Oxygen   Transfer  Efficiency
       Measurements in Mixed  Liquor Using Offgas  Techniques." J.
       Hater Pollution Control  Federationf 55,  1338 (1983).

 9.     ASCE  -  "Standard  for   Measurement of  Oxygen transfer  in
       Clean Water."  (1984).

 10.    Redmon,  D.T.,  et al.,   "Experiences  in   Field  Testing  a
       Variety of Aeration  Equipment in Sweden and  in  the U.S A
       by  Offgas   Anlysis",   IAHPRC  International Conference.
       Brighton, UK,  July,  (1988).                     !
                                                      i
 11.   Ewing,  L.,  et  al.,  "Oxygen  Transfer  Measurement  by  the
      Offgas Procedure  -  Its  Development and  Apllication"  HPCF
      Conference,  Dallas, October,  (1988).            !

 12.   Benedek, A.,    "Problems  with  the  Use of Sodium i  Sulfite in
      Aerator Evaluation." 26th Indust.   Haste Conference,  Purdue
      University,  (1971).

13.   Allbaugh,  T. A.,  et  al. , "Aeration  System  Design   Using
      Offgas Oxygen Transfer Testing."  5Sth Annual  Meeting Hater
      Pollution Control Federation,  (1985).
                               99

-------
14.
Boyle,  W.C. , et  al.,  "Biological   Fouling of
Diffusers:  State-of-Art",  Journal   of  the
Engineering  Division,    ASCE   1O9CEE5):991-1OO5
(1983).
15.
16.
Costerton, J.W., "Investigations   into Biofouling Phenomena
in  Fine  Pore  Aeration Devices",   Study  conducted  under
                           —	:	—  7   »— *.*-•«-* jr   ^.i«ri iu<
Cooperative Agreement CR812167,   Risk Reduction
Laboratory, U.S.  EPA,  
-------
   APPENDIX
     MONROE, WISCONSIN
 Full-Seal e Qf-Fgas Results
June, 1986 - November,  1987
           101

-------
DATE
          THE   STATION   fiRIB

                                                       AI-1


                                      HONROE   FULL-SCALE   OTE    DATA


                                                 6RID VERSUS CALENDAR  THE


                                                             MERASE     AVERA8E
                                            «LT     AVERABE
08"Jul~B6 1107-1208 21 9 i
*•* til Q.54i 21#2 0.4 5 73
flWuI-tt 1430-1530 2.3 2.2 0.410 21.6 0.2 . 2.05
1600-1648 2.4 2.2 0.303 21.6 0.1 1.52
08-JU1-S6 1137-1154 U ,., ^ ^ ^ ^
08-Jul-8,i 1313-1327 1.2 ' 1.1 0.642 21.5 0.8 3.21
08-Jul-Sf, 1447-1508 1.3 1.2 0.364 21.6 0.1 {M
08-JU1-8M531-1613 1.4 r.2 0.265 21.6 0.1 ,.jj
.OS-Jul-86 1726 1.5 . 1.3 0.216 21.9 - 2.4. hOB
OB-Jul-86 1746 1.6 1.3 0.217 22.0 2.6 ' 1.09
08-Jul-86 1819 1.7 1,4 0 156 25 fl
OS-Jul-86 1843 1.8 ,.4 0.139 22.0 2.3 0.70
09-JU1-86 0905 2.1 2.1 0.584 21.5 0.4 2.92
09-JU1-B6 0927 2.1 2.1 O.J72 21.5 0.2 1.B6
09-Jul-86 1009 '2.1 2.1 0.155 21 3
0.78
09-JU1-B6 1049 2.4 2.2 0.479 21.3 0.1 2.40
'oWQl-86 1131 2.4 2.2 0.418 21.3 0.5 2.09
09-M-86 ,153 2.4 2.2 0.338 21.3 0.6 1.70
09-JU1-86 1511 2.1 2.1 0.370 21.6 0.1 ,.85
09-JU1-86 1440 2.2 2.1 0.354 21.5 0.1 1<77
09-JU1-86 1355 2.3 2.2 0.461 21.5 0.1 2.31
— s333-3s3*si3saaszaaa3aaaM3
38 4 0. 0665
26 6 0.0871
26 6 0.1060
50 3 0.0562
50 3 0.0503
26 6 0.1091
26 6 0.0962
26 6 .0.0796"
26 6 0.0996

26 6 0.0786
26 6 0.0863
38 4 fl.0700
38 4 0.0850
38 4 0.0812
26 6 0.0936
26 6 0.0830
26 6 0.0870
38 4 0.0802
38 4 0.0736
26 6 0.0656
f
i 0.1071
' 0.0630
i 0.0549
0.1110
0.0974
jO.tOSB
0.1360

0.1120
0.1320
6.0735
0.0872
0.0821
1
0;0954
010883
010933
i
0.0816
i
O.|0746
0.0669
0.2'
0.2(
«
0.27
0.24
0.43
0.39
0.38
0.49

0.37
0.37
0.31
0.35
0.28
0.38
0.35
0.36
0.32
0.29
0.27
                                                    102

-------
      AI-1   - Continued




HOKROE   FULL-SCALE   OTE   0ATA



         BRID VERSUS CALENDAR TIKE
DATE
53333333333
09-M-84
09-Jul-B4
09-,lul-84
09-M-84
09-Jul-84
09-Jul-84
09-Jul-84
09-J»l-84
09-Jul-84
09- Ju 1-84
09-Jul-84
09-M-84
09-JuI-84
09-M-B4
09-JuI-84
TINE STATION 8RIB
:>333S33:3*3Z3333333S333333:
1327 2.4 2.2
1410 2.4 2.3
1550 2.7 2.4
0850 1,1 l.l
0939 1.1 l.l
0958 1.1 l.l
1105 1.4 1.2
1117 1.4 1.2
1207 ' 1.4 1.2
1522 1.1 l.l
1428 1.2 1.1
1404 1.3 1.2
1314 1.4 1.2
1709 1.4 1,3
1450 1.7 1.4
FLT^E
,33333:33:33
0,402
0.295
0.243
0.544
0.371
0.232
0.480
0.388
0.325
0.384
0.441
0.441
0,373
0.295
0,201
KIT AVERA8E
=33=S33.-3=33333=;=333*
21.7 0.1
22.0 3.0
22.0 3.7
21.5 1.9
21.4 0.2
21.4 0.1
21.3 0.2
21.3 0.2
21.5 0,3
21.4 0.4
21,5 0.1
21.5 0.1
21.7 0.5
22,0 2.1
22.0 2.4
AIRRATE
»»333»ff:
2.01
1.48
1.24
2.83
1.84
1.14
2.40
1.94
1.43
1.93
2.31
2.31
1.87
1.48
1.01
SPECIFH
^33«fL
24
24
24
SO
50
50
24
24
24
SO
50
24
24
24
24

BRVa OTE(f) ;
i
4 0.0742 ;
4 0.0978 :
4 0.0851 i
3 0.0440 !
3 0.0488
3 0,0749 ;
& 0.1011
4 0.0958 ',
4 0.1082 i
3 0.0458
3 0.0394 :
4 0.0734 :
4 0.0970
4 0.1048
4 „..._ 0.0941 .!..
AVERASE
SQTE
0,0774
0.1414
0.1370
0.0573
0.0704
0.0741
0,1040
0.0988
0.1127
0.0449
0.0402
0.0748
0.1024
0.1340
0.1313
AVERASE
APPARENT

0,31
0.53
0.50
0.25
0.29
0,30
0.42
0.39
0.43
0.28
0.24
0.30
0.40
0.50
0.44
       103

-------
                AI-2





HONROE   FULL-SCALE   OTE   DATA



           BRIO VERSUS CALENDAR TINE
HATE
20-Nov-84
20-NDV-84
20-Nov-84
20-Nov-84
20-»o»-84
20-UOV-84
20-ltev-84
20-llov-84
21-NOV-84
21-NDV-B4
21-NBV-84
21-NOV-B4
21-N«»-84
21-NHV-84
21-Nciv-B4
21-Nav-fl4
21-HOY-84
21-Niw-84
21-KOV-B4
21-Nmr-84
21-NOV-84
21-Nov-84
TIKE STATION 8RID
1240-1309 1.1 1.1
1330-1404 1.2 1.1
1432-1509 1.3 1.2
1531-1544 1.4 1.2
1249-1259 2.1 2.1
1342-1353 2.2 2.1
1441-1433 2.3 2,2
1523-1537 2.4 2.2
0815 3.1 3.1
0844 3.2 3.1
0909 3.3 3.2
1001 3.4 3.2 •
1009 3.5 3.3 -
0950 3.4 3.3
0854 3.7 3.4
0830 3.8 3.4
1052 1.1 1.1
1115 1.2 1.1
1137 1.3 1.2
11S4 1.4 1.2
1252 1.5 1.3
1240 1.8 1.4
AVERASE
FLUI RATE
0.354
0.419
0.354
0,380
0.347
0.294
0.327
0.345
0.319.
0.428
0.311
0.319
0.238
0.322
0.195
0.174
0.291
0.389
0.341
0.342
0.275
0.195
HLT
°C
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
HVlXWt AVERABE
AVERA8E AIRRATE SPECIFIC '
___J-0- _ PER BIFFUSER PERM BRV0 DTEHi;
2'4 I'M 50 3 0.05771
1-0 2.10 50 3 0.0540;
M 1-77 24 4 0.0441 i
°'4 LW 24 4 0.0587 i
°-8 1.74 38 4 0.0444 i
i
°'4 «.47 38 4 0.0430 j
«•» 1-43 24 4 0,0420
I'5 . 1-72 24 4 * 0.0587 '
1.2 1.40 24 4 - 0.0594 i
M 2-t4 24 4 0,0424 j
°'7 I'54 24 4 0.0444 ;
'•3 1-W 24 4 0.0522
110 '-I' 24 4 0.0448 1
5'8 1.41 24 4 0.0410 ;
*•* 0.98 24 4 0.0479
ilS O.B8 24 4 0.0381 '
3-° !•« 50 3 0,0534
I"3 1-95 50 3 0.0511
°'3 1.81 24 4 0,0448 '•
°-3 1-71 24 4 0.0530
3'3 1-38 24 4 0.0594 •
3-5 0.98 24 4 0.0507 j
AVERASE
ALPHA
SOTE
0.0755
0.0432
0.0490
0.0428
0.0714
0.0474
0.0493
0.0702
• 0.0485
0.0700
0.0732
0.0408
0.0832
0.0871
0,1145
0.0929
0.0754
0.0598
0.0487
0.0544
0.0870
0.0741 '
AVERA6E
APPARENT
ALPHA
0.31
0.27
0.27
0.25
0.28
0.24
0,27
0.27
0,24
0.28
0.28
0.23
0.30
0.33
0.40
0.32
0.30
0.25
0.27
0.22
0.32
0.27
          104

-------
      AI-2  -  Continued




MONROE   FULL-SCALE   OTE   DATA



         6R1B VERSUS CALENDAR TldE
DATE TIKE
=a==:zsa=a333zaz33asa
21-Nov-B6
21-Nov-86
21-iHov-86
21-MOV-86
21-IIOV-86
21-IIOV-86
1100
1126
1145
1201
1216
• 1227
STATION 6RID
asasaaaaaaasasasaa:
2.1
2.2
2.3
2.4
2.5
2.8
2.1
2.1
2.2
2.2
2.3
2.4
AVERASE
FLM RATE
rasaaaaasazs
0.322
0.308
0.370
0.370
0.256
0.289
HLT
"C
15.0
15.0
15.0
15.0
15.0
15.0
AVERASE
0.0.
1.3
0.3
0.4
0.8
5.0
6.4
AVERASE
AIRRATE
PER DIFFUSER
1.61
1.54
1.85
1.85
1.28
1.45
AVERASE
SPECIFIC
PERK
38
38
26
26
26
26
BRV0
4
4
6
6
6
6
OTEK) ;
" ""* . j-
1
0.0651 ,
0.0591 ;
0.0579 :
0.0592 '-,
0.0493 !
0.0480 |
AVERASE
ALPHA
SOTE
0.0762
0.0628
0.0622
0.0660
0.0915
0.1135
AVERASE
APPARENT
ALPHA
0.30
0.24
0.24
0.26
0.34
0.43
          106

-------
MONROE    FULL-SCALE   OTE    DATA



           6R10 VERSUS MLEMDAR TIK

twit Tine STATION BRIO
05-Hay-B7 1332 1.1 l.l
05-H»y-B7 1424 1.2 1.1
05-Hay-87 1346 2.1 2.1
05-ft«y-87 1416 2.2 2.1
05-«jy-87 1445-1510 3.1 3.1
05-Hay-87 153S-1542 3.2 3.1
05-Nay-87 1457-1518 3.8 3.4
05-«ay-87 1553 3.7 . 3.4
06-Hay-87 1047-1112 1.1 l.l
06-Hay-87 1003-1029 1.2 1.1
06-Hay-87 1221-1238 1.3 1,2
06-Hay-B7 1312-1327 1.4 1.2
06-Hay-87 1618 1.5 1.3
06-Nay-87 1632 1,6 1.3
06-N*y-87 1642 1.7 1.4
06-«ay87 1656 1.8 1.4
06-Hay-87 1056-1106 2.1 2.1
06-May-87 1011-1023 2.2 2.1
06-Hay-87 1231-1245 2.3 2.2
06-Hay-B7 1320-1334 2,4 2.2
06-May-U7 1521 2.5 2.3
06-Hay-B7 1541 2.6 2.3
AVERA8E
SVERftBE m.T AVERSfiE AIRRATE
AVE8A6E
; AVERA8E
ABBXfimv
.^JJIL. °° D-°- PER ™m3i PER" BRV° mw ; lire "air"
	 "S"SS""='"I3=:I!!3IsaSE:ss3s=s«««=«»»»»««=«««»««:»xs«KS3J^s
0.398 16.4 2.1 1,99
0.388 16.4 2.3 1.94
0.344 16.4 1.2 1.72
0.305 16.4 1.2 1.53
0.256 16.4 0.8 1.28
0.277 16.4 0.8 1.39
0.130 16.4 5.3 0.65
.0.134 16.4. 5.4 .0.67
0-285 16.7 1.0 o.U
0-311 16.7 1.6 o.ii
0.223 16.7 1.0 l.u
0-268 16.7 l.l 1,34
0,195 16.7 3.7 0.98
0-184 16.7 3.6 0.92
0.150 16.7 3,8 0.75
0.173 16.7 3.8 0.87
0.335 16.7 1.2 1.47
0.279 16.7 1.4 1.40
0.316 16.7 1.5 1.58
0.259 16.7 1.4 1.29
0.130 16.7 4.7 0.65
0.188 16.7 4.8 0.94
50 3 0.0601
50 3 0.0691
38 4 0.0651
38 4 0.0716
26 6 0.0838
26 6 0.0979
26 6 0.0519
26 6 .. 0.0592
SO 3 0.0706
50 3 0.0785
26 6 0.0925
26 6 0.0828
26 6 0.0683
26 6 0.0861
26 6 0.0734
24 6 0.0645
38 4 0,0625
38 4 0.0769
26 6 0.0855
26 6 0,0743
26 6 0.0660
26 6 0.0723
0.0760
!
{ 0.0893
1
1 0.0748
0.0822
i
0.0926
1 .
i 0.1092
f
' 0.1010
: 0.1178
: 0.0802
• 0.0948
I
; 0.1048
; 0.0937
! 0.1049
i 0.1312
! 0.1150
: 0.1004
0.0717
\ 0.0911
! 0.1017
0.0877
i 0.1179
0.1314
0.32
0.37
0.29
0.32
0.35
0.41
0.33
0.38
0.32
0.38
0.38
0.35
0.37
0.45
0.38
0.34
0.28
0.35
0.39
0.32
0.38
0.46
             106

-------
      AI-3 -  Continued




NOKROE   FULL-SCALE   OTE   DATA



         SfilD VERSUS CALENDAR TIME
__ OWE TIKE STATION 6RID
04-lliy-87 1550 2.7 2.4
04-llsy-87 1401 2.8 2.4
'04-H»y-B7 0852-0903 3.1 3.1
04-Hay-87 0823-0839 3.2 3.1
04-ftjy-B7 1407-1422 ' 3.3 3.2
04-H,iy-87 1442-1451 3.4 3.2
04-Hiiy-87 143! 3.! 3.3
04-Hj,y-S7 141! 3.4 3.3
04-Hiy-87 0829 3.7. 3.4
04-H»y-87 0910 3.8 3.4
07-H»if-87 1009 3.2 3.1
07-H»y-87 0948 3.4 3.2
07-Hay-87 0937 3.5 3.4
07-Hay-87 1014 3.8 3.4
07-my-87 1040 1.8 1.4
07-Hay-87 1030 2.8 2.4
07-H»y-87 1131 1.2 j.j
07-Hiy-37 122! 1.2 1.1
07-Kay-H7 1321 1.2 j..j

AVERABE HLT AVERA8E
FLU! RATE °c D.O.
iwssassasaaiaasassiassaasssasasaa
0.195 14.7 4.9
0.154 14.7 4.7
0.300 14.7 2.4
0.332 14.7 2.4
0.240 14.7 1.2
0.281 U.7 1.5
0.270 14.7 5.5
0.283 14.7 4.1
0.170 14,7 4.4
0.170 14.7 4,5
0.305 17.0 1.5
0.355 17.0 3.0
0.259 17.0 6.5
0.19! 17.0 4.5
0.140 17.0 5.4
0.191 17,0 5.8
0.292 17.0 1.5
0.177 17.0 0.4
0.434 17.0 1.2

nitnnoE HYtWHJt
AI8RATE SPECIFIC
PER DIFFUSES PERM BRV0 OTE«)
SSSSSSSSSSS SS33 aa-sj-as-s-i .jjj.--^^^ ,.sgm


0(98 24 4 0.0741
°'7B 24 4 0.0440
i-50 24 4 0.0728
'•" 24 4 0.0825
'•SO 26 6 0.0892
l.« 26 4 0.0723
'•35 24 4 0.0478
l-« 26 6 0.0444
• °-B 24 4 .. 0.0449
0-85 24 4 0.0461
1
-------
 07-«ay-87    1148      1.4      1.2

 07-»iy-B7    1217      1.4      1.2

 07-H,iy-B7    1329      1.4      1.2




 07-Miiy-87    1139     2.2      2.1

 07-«jy-87    1233     2.2      2.1

 07-Hjy-87    1313     2.2      2.1




07-Hay-87    1157     2.4      2.2

07-Nay-B7    1210     2.4      2.2

07-Hay-87    1339     2.4-     2.2
                                                      AI-3  -  Continued


                                              HONROE    FULL-SCALE   OTE    DATA

                                                          6RIO VERSUS CALENDAR  TIKE


                                                    KIT     AVERA6E
   0,328     17.0

   0.328     17.0

   0.109     17.0




   0.336     17.0

   0.109     17.0

   0.378      17.0
  0.292

  0.328

.  0.128
17.0

17.0

17.0
 1.5

 2.1

 0.6




 0.9

 0.3

 0.9




 1.5

 1.3

.0.5
 1.64

 1.64

 0.55




 1.68

 0.55

 1.89




 1.46

 1.64

0.64
                                                                                                  o      OTEff)
                                                                                                  ==s=r=s=sssr=s
                                                                                SOTE
                                      26     6

                                      26     6

                                      26     6
 38

 38

 38




26

26

26
 4


 4


 4




6

6


6
 0.0876

 0.0833

 0.1115




 0,0628

 0.0793

 0.0650




0.0803

0.0854

0.0862
                                                                               AVERA6E

                                                                               ALPHA
  0.1040         0.40

  0.1055         0.40

  0.1203         0.37




  0.0701         0.27

 0.0836         0.26

 0-0725         0.29




 0.0953        0.36

 0.0993        0.38

•0.0926        0.30
                                                          108

-------
                    AI-4




HOMROE    FULL-SCALE   OTE    DATA



           6RID VERSUS CALENDAR  TINE
DATE TIKE STATION 6RI0
17-Aug-87 141H432 1.1 l.l
17-Aug-87 1551-1608 1.2 1.1
17-Auij-87 1644-1654 1.3 1.2
17-Auj|-87 1400-1441 2.1 2.1
17-Aur87 1541-1414 2.2 2.1
17-Auj-B7 1636-1708 2.3 2.2
18-Aug-87 1429-1438 1.1 1.1
18-Aug-87 1247-1258 1.2 1.1
18-Aug-87 1159-1209 ' 1.3 1.2
18-Aug-B7 1535-1544 1.4 1.2
lB-Aug-87 1912 1.5 1.3
lB-Aug-87 1929 1.6 1.3
18-Aug-87 1958 1.7 1.4
18-Aug-B7 2009 1.8 1.4
lB-Aug-B7 1420-1457 2.1 2.1
18-Aug-37 1238-1307 2.2 2,1
18-Aug-87 1148-1225 2.3 2.2
18-Aug-ll7 1529-1550 2.4 2.2
lB-Aug-SI7 1417-1423 3.1 3.1
18-Aug-87 1744-1750 3.2 3.1
18-Aug-87 1802-1808 3.3 3.2
lB-Aug-87 1833-1842 3.4 3.2
,
AVERABE
AVERABE HLT AVERABE AIRRATE
FLUI RATE °C D.O. PER DIFFUSER
0.314 24.2 4.8 1,57
0.372 24.2 5.2 1.84
0.284 24.2 5.4 1.42
0.291 24.2 4.4 1.45
0.343 24.2 4.3 1.72
0.310 24.2 4.9 1.55
0.434 23.4 5.7 2.17
0.432 23.6 6.0 2.16
0.2B1 23.6 6.1 1.40
0.259 23.6 6.2 1.30
0.206 23.4 7,2 1,03
0.245 23.4 7.2 1.23
0.166 23.6 6.8 0.83
0.138 23.6 6.4 0.69
0.355 23.4 5.7 1.78
0.397 23.4 5.9 1.99
0.317 23.4 4.0 1.58
0.309 23.6 6.4 1.54
0.280 23.6 5.1 1.40
0.311 23.4 5.3 1.55
0.262 23.6 5.5 1.31
0.274 23.6 6.1 1.37
109
AVERAEE
SPECIFIC
PERK BRVo OTEK)
SO 3 0.0731
50 3 0.0589
26 6 0.0691
38 4 0.0702
38 4 0.0642
26 6 0.049B
50 3 0.0554
50 3 0.0533
26 6 0.0450
26 4 0.0434
26 4 0.0544
26 4 0.0405
26 6 0.0716
26 6 0.0578
.38 4 0.0506
38 4 0.0588
26 6 0.0677
26 6 0.0562
26 6 0.0818
26 6 0.0709
26 6 0.0728
26 6 0.0535

. AVERABE
ALPHA
SOTE
| 0.1479
0.1304
0.1438
0.1368
0.1179
0.1460
0.1359
0.1414
0.1784
: 0.1788
', 0.2298
; 0.2405
0.2442
1 0.1750
0.1255.
0.1520
0.1801
! 0.1748
0.1728
0.1597
0.1714
0.1485

AVERAGE
APPARENT
Al PHA
0.60
0.54
0.62
0.52
0.46
0.56
0.57
0.60
0.64
0.44
0.81
O.B8
0.83
0.57
0.50 .. ...
0.60
0.68
0.66
0.65
0.60
0.43
0.55


-------
      AI-4  - Continued




HO MR HE   FULL-SCALE   OTE   DATA



         BRID VERSUS CALENDAR TIME
JSL^LSLSL.

lB-A«g-87 1825 3.5 3,3
18-Aug-87 1815 3.6 3.3
18-Aug-87 1734 3.7 3.4
18-Aug-B7 1431 3.8 3.4
19-Auij-87 0904-0911 3.1 3,1
19-Au(|-87 0841-0848 3.2 3.1
19-Auj|-B7 0818-0827 3.3 3.2
19-Auj-B? 0749-0803 3.4 3.2
19-Aug-B7 0808 3.5 3.3
19-Aug-B7 0854 '3.7 3.4
19-Aug-87 1246-1257 1.1 i.|
l?-Aug-B7 1216-1222 1,2 1.1
19-Aug-87 1135-1144 1,3 1,2
19-Agg-87 1050-1059 1.4 1.2
19-Aug-B7 1240-1304 2.1 2.1
19-Aug-37 1207-1228 2.2 2,1
19-Aug-l)7 1129-1151 2.3 2.2
19-Aug-fl7 1043-1103 2.4 2.2
19-Aug-ii7 0952 2.5 2.3
19-Aug-87 1004 2.4 2.3
19-Aug-87 1013 2.7 2.4
19-Aug-B7 1025 2.8 2.4
FL™EE

0.270
0.305
0.144
0.149
0.294
0.309
0.281
0.280
0.305
0.248
0.343
0.347
0.299
0.289
0.337
0.326
0.356
0.306
0.264
0.264
0.254
0.254
IH.T AVERA6E

23.4 7.3
23.4 7.3
23.4 7.0
23.4 . 6.6
23.0 5.4
23.0 5.8
23.0 6,0
23.0 6.5
23.0 7.3
23.0 6.9
23.0 5.2
23.0 5.7
23.0 6.0
23.0 4.4
23.0 5.4.
23.0 5.4
23.0 5.8
23.0 6.6
23.0 7.6
23.0 7.4
23.0 7.2
23.0 6.9
AVERASE
A1RRATE
PER DIFFUSES

1.35
1.53
0.83
0.85
1.48
1.54
1.41
1.40
1.53
1.24
1.72
1.74
1.49
1,45
1.69.
1.63
. 1.78
1.54
1.32
1.32
1.28
1.28
AVERA6E
MswanEBSMssKsMssaassss:
24 6 0.0531
24 4 0.0494
24 4 0.0718
24 6 0,0608
24 . 6 0.0774
24 6 0.0688
24 6 0.0665
24 6 0.0495
24 6 0.0392
24 6 0.0680
5(> 3 0.0555
SO 3 0.0591
24 4 0.0660
24 6 0.0544
38 4 0.0567
38 4 0.0691
24 6 0.0667
24 4 0.0584
24 4 0.0451
24 4 0,0452
24 4 0.0604
26 4 0.0550
i
• AVERASE
i ALPHA
; SOTE
tasaeccasaasxss:
1 0.2204
i 0.2051
; 0.2635
i 0.1948
, 0.1494
! 0.1470
!
: 0.1447
0.1442
i
' 0.1517
j 0.2270
i 0.1170
i 0.1394
: 0.1457
: 0.1562
1
; 0.1237
: 0.1587
i 0.1632
i
I 0.1776
i
0.1940
i 0.1862
0.2205
0.1837
AVERASE
APPAREX1
ALPHA
rx333S3X3I31
0.82
0.78
0.89
0.47
0.64
0.63
0.42
0.54
0.57
0.83
0.48
0.57
0.63
0.58
0.48
0.62
0.63
0.67
0,72
0.69
0,81
0.68

-------
               AI-5




HONROE   FULL-SCALE    OTE    D A T A



          6R1D VERSUS CALENDAR TIKE
DATE TIKE STATION BRIO
03-NOV-87 1632-1455 1.1 l.l
03-Nov-B7 1547-1411 1.2 1.1
03-NOV-B7 1440-1511 1.3 1.2
03-Nov-87 1353-1403 1.4 1.2
03-Nov-87 1438-1444 2.1 2.1
03-NOV-87 1555-1404 2.2 2.1
03-Hov-87 1451-1502 2.3 2.2
03-Nov-87 1345-1410 2.4 2.2
. 03-NOV-87 1022-1032 .3,1 ' 3,1
03-Nov87 1111-1118 3.2 3.1
03-Mov-87 1131-1139 3.3 3.2
OS-Nov-87 1205-1213 3.4 3.2
03-NOV-87 1158 3.5 3.3
03-NBV-B7 1MB 3.4 3.3
03-NOV-B7 1059 3.7 3.4
03-Hav-87 1040 3.8 3.4
04-Nov-87 0854-0930 1.1 u
04-Nov-fl7 0820-0843 1.1 l.l
04-Nov-6i7 1015-1037 1.2 1.1
04-Nov-87 1053-1113 1.3 1,2
04-NOV-87 1130-1152 1.4 1.2
04-Hov-B7 1221 1.5. 1.3
AVERA8E
FUJI RATE
0.508
0.530
0.489
0.444
0.514
0.487
0.494
0.509
0.433
0.535
0.441
0.448
0.333
0.441
0.300
0.289
0.214
0.519
0.552
0.490
0.472
0.300
HLT AVERASE
°C D.O.
z— ====S===SSIK:ZI=
20.0 1.0
20.0 O.B
20.0 0.4
20.0 0.6
20.0 0.9
20.0 0.7
20.0 0.4
20.0 0.5
20.0' 1.0
20.0 0.5
20,0 0,6
20.0 0.6
20.0 4.0
20.0 5.0
20.0 5.4
20.0 5.7
20.0 0.4
20.0 1.9
20.0 0.7
20.0 0.3
20.0 0.4
20.0 3,4
HVCHHBE RVtKHS
AIRRATE SPECIFIi
PER OIFFUSER PERK
3=— IISSSSZSISMIIIZSS:
2.54 50
2.45 SO
2.44 26
2.32 26
2.57 38
2.43 38
2.48 26
2.54 26
2.16 26
2.67 24
2.20 26
2.24 24
1.67 26
2.21 26
1.50 26
1.45 26
. 1.08 50
2.59 50
2.76 50
2.45 26
2.36 26
1.50 26
BRVo OTEK 1 ;
— =3=S— =33£3S33=a333Z2:
f
3 0.0637 i
3 0.0637 ;
6 0.0648 ;
6 0.0688 '
. 4 0.0424 i
4 0.0434 |
6 0.0643 ;
6 0.0440 ;
6 •" 0.0452 :
6 0.0474 !
6 0.0596 :
4 0.0574 i
6 0.0519
6 0.0444
6 0.0493 ;
6 0.0417 '
.1
3 0.0831
i
3 0.0637
3 0.0650
6 0.0554 |
6 0.0608 ;
6 0.0757 1
AVERA6E
ALPHA
SOTE
K3ii=iz3i2=
0.0732
0.0708
0.0685
0.0745
0.0706
0.0706
0.0699
0.0712
0:0745
0.0521
0.0463
0.0650
0.0885
0.0905
0.1124
0.0975
0.0898
0.0808
0,0719
0.0588
0.0453
0.1179
AVERA5E
APPARENT
ALPHA
5=223 STSSS
0.31
0.30
0.28
0.30
0.29
0.29
0.28
0.29
0.30
0.21
0.24
0.24
0.34
0.36
0.42
0.37
0.35
0.33
0.31
0.24
0.26
0.44
             111

-------
       AI-5  - Continued




HONDOE   FULL-SCALE   OTE   DATA



         BRIO VERSUS CALENDAR TIKE
DA1TE TIKE
04-Xov-87 1236
fl4-Nov-87 1244
04-NOY-87 1259
04-KOV-87 0901-0924
04-NOV-87 0827-0837
04-Xav-87 1021-1031
04-Nov~87 1058-1107
04-KBV-87 1137-1145
04-Hov-87 1316
04-NOV-B7 1327
04-NOV-87 1338
04-KOV-87 1349
STATION
1.6
1.7
1.8
2.1
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
BRIO
1.3
1.4
1.4
2.1
2.1
2.1
2.2
2.2
2.3
2.3
2.4
2.4
AVERA8E
FLUI RATE
0.363
0.269
0.263
0.228
0.533
0.466
0.536
0.474
0.353
0.378
0.284
0.288
°C D.O,
20.0 3.8
20.0 4.4
20.0 4.5
20.0 0.4
20.0 1.4
20.0 0.5
20.0 0.3
20.0 0.4
20.0 3.1
20.0 4.4
20.0 4.8
20.0 5.0
AVERASE
PER OIFFUSER
1.82
1.35
1.32
1.14
2.67
2.33
2.68
2.37
1.77
1.89
1.42
1.44
AVERA8E
SPECIFIC
PERM BRVg
26 6
26 6
26 6
38 4
38 4
38 4
26 6
26 6
26 6
26 6
26 6
26 6

OTE(f)
0.0679
0.0702
0.0645
0.0778
0.0637
0.0567
0.0584
0.0651
0.073!
0.0674
0.0589
0.0513
AVERAEE
SOTE
0.1121
0.1269
0.1190
0.0836
0.0765
0.0620
0.0622
0.0698
0.1086
0.1228
0.1163
0.1050
AVERA6E
APPAREN1
ALPHA
naasxEai
0.43
0.47
0.44
0.31
0.32
0.25
0.25
0.28
0.42
0.48
0.44
0.39
           -142

-------
           APPENDIX       II
MONROE, WISCONSIN WASTEWATER TREATMENT PLANT!
        19S& ANNUAL OPERATING REPORT
             By Gerald Ellofeon



            Plant Superintendent
                   113

-------
                     CITY   of   MONROE
                              WASTE WATER TREATMENT PLANT
                                                           March 8, 19:B7
                                        TREA3MENT PLANT
                             1986 ANNUAL OPERATIONS REPORT
  1.  WASTEWRTER TREATMENT PLANT WORK HJNCTICNS
     d.  Assist with inspection and construction of the'wro facilities.
 2.- OPERATION AND MAINTENANCE PERSONNEL                     "          '



 3.   SUMMARY OF OCWSTRtJCTICN






4.   S^MIARY OF OPERA1TON                                              !
                                114

-------
1986 ANNUM, OPERATIONS REPORT (con't)

5.  su^MAsy OF OPERATIONAL EXPENSE


   5

              10?1 P^61 ^ dr°fPed by over 2160 KWH per day or about
  L
                               g? ?r as s

                                    Respectfully Submitted
                                    Gerald V. Ellefson
                                    Plant Superintendent
                           115

-------
CITY  of   MONROE
        WASTE WATER TREATMENT PIANT
          WWTP LOADINGS 1986
MONTH

January
February
March
April
May
June
July
August
September
October
November
Decerrtoer
TOTAL
AVERSGE
FLOW
(gal)
56,938,000
54,640,000
73,778,000
61,616,000
69,222,000
65,029,000
66,176,000
66,567,000
77,724,000
78,265,000
63,191,000
62,819,000
795,965,000
66,330,417
BOD
(FF)
236,506
222,227
242,101
207,364
232,767
235,858
269,148
217,519
247,061
230,558
195,376
203,945
2,740,431
228,369
TSS
(i's)
112,978
100,675
123,234
108,716
115,571
126,027
133,113
121,560
191,597
152,730
133,648
119 ', 985
1,539,834
128,320
Monthly total for BCD and TSS are estimated, because
S3                              ^« -» -
Flow data results are for all days of every manth.
                                         did
            116

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1986 WASTEKATSR TREATMENT PLANT LOADING


JANUARY
FEBRUARY
. MARCH
APRIL
MAY
JUNE
JULY
AUGUST
SEPTEMBER
OCTOBER '
NOVEMBER
DECEMBER
TOTAL
AVERAGE
FLOW
MGD
1.837
1.951
2.380
2.054
2.233
2.168
2.135
2.147
2.591
2.525
2.106
2.026
26.153
2.179
a
RAW
22/1
494
484
397
401
415
434
483
392
397
360
370
386
5,013
418
Ibs.
7,629
7,937
7,810
6,912
7,729
7,862
8,682
7,019
8,579
7,560
6,513
6,578
90,810
7,568.
\JU
FINAL
52/1
99
78
26
43
22
25
17
15
12
7
6
	 9
359
30
Ibs.
1,699
1,269
516
737
410
452
303
269
259
147
105
152
6,318
527
22/1
237
218
- 201
211
202
231
239
217
286
237
253
227
2,758
230
TSS:
SAW ; FINAL
Ibs.
3,644
3,596
3,975
3,624
3,762
4,201
4,294
3,921
6,387 .
4,991
4,455
3,870
50,720
4,227
:22/i
168
j!08
i 21
1 38
11
I
12
9

10
1 4
; 4
i
1 6
401
!33
Ibs.
2,574
1,757
417
651
205
217
160
17Q
-i/y
216
QA
o*t
70
101
6,631
553
              117

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GALLONS SEKAGE TREATED 1986

JANUARY
FEBRUARY
MARCH
APRIL
MAY
JUNE
JULY
AUGUST
SEPTEMBER
OCTOBER
NOVEMBER
DECEMBER
TOTAL
AVERAGE

QUARTER
1st
2nd
3rd -
4th
Total
AVG.
GALLONS
56,938,000
54,640,000
73,778,000
61,616,000
69,222,000
65,029,000
66,176,000
66,567,000
77,724,000
78,265,000
63,191,000
62,819,000
795,965,000
66,330,417
EXTRA STRENGTH
FLOW
21,231,949
22,576,716
24,649,838
24,386,270
92,844,773
23,211,193"
AVERAGE FLOW
1.837
1.951
2.380
2.054
2.233
2,168
2.135
2.147
2.591
2.525
2.106
2.026
26,153
2,179
INDUSTRY 1986
BOD
201,183
271,792
238,571
251,688
963,234
240,809
% OF CITY WATER
86
89
108
90
94
86
82
86
108
110
<
99
Qfi
70
1134'
95 :
j
1
TSS ;
i
110,442 :
113,745 I
	 100,024
110,737
434,948 ;
108,737 ..
      4.18

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ELECTRICAL POWER PORCHASFJl - 1986
   POWER USAGE
ON PEAK   OFF PEAK
              KWH
                          POWER
January
February
March
April
June
July
August
September
October
November
December
TOTAL
AVERAGE









39 61
45 55
41 59
-44 56
44 56
41 59
43 57
45 55
41 59
45 55
44 56
-JO 60
512 688
43 57

QUARTER
1st / March
2nd / June
3rd / September
4th / December
TOTAL
AVERAGE
Total cost for
fire line, $66.
144,000
129,600
148,500
151,200
158,400
162,000
152,400
179,400
210,600
203,400
203,400
266,400
-*-/Tt— xwr\
78
76
78
78
77
77
77
77
76
74
72
76
2,109,300 916
175,775 76
PLANT WATER USAGE -
CUBIC FEET
65,340
93,450
73,800
,46,640
279,230
69,808
4th Quarter includes
00 per quarter.
1986
GALLONS
488,743
699,006
552,024
348,867
2,088,640
522,160
new roeter
$0.045 $ 6,529.09
0.052 ' !6,676.32
0.049 ,7,245.77
0-048 7,266.43
0-049 17,719.98
0.048 7,822.03
0.043 6,524.01
0.043 7,785.69
0.042 8,795.18
0.045 9,203.45
0.042 8,591.53
0.040 10,699.26
$0.546 $ 94,858.74
$0.046 .$ 7,904.90
•
\
COST
$ 257.49 '
$ 355.88 \
$ 287.10 ;
$ 349.77 *
$ 1,250.24
$ 312.56 :
installed and:
TOTAL ENGINE HOURS - 1986 '
         TOTAL  646.7

        AVERAGE 161.7
          119

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               CHLORINE USED - 1986
 JANUARY
 FEBRUARY
 MARCH
 APRIL
 MAY
 JUNE
 JULY
 AUGUST
 SEPTEMBER
 OCTOBER
 NOVEMBER
 DECEMBER
 TOTAL
AVERAGE
COST $18.50
TOTAL #'s
2,377
1,207
2,497
1,309
1,172
2,409
4,059
3,620
6,287
4,919
4,903
4,009
38,768
3,231
/ cwt
TOTAL COST
$ 439.75
223.30
461.95
242.17
216.82
445.67
750.92
669.70
1,163.10
910.02
907.06
741.67
$ 7,172.13
$ 597.68
         SULPHUR DIOXIDE USED - 1986
              COST:  $23.00 / CWT
         TOTAL POUNDS:           8,562
        . MONTHLY AVERAGE:          714
         TOTAL COST:       $ 1,969.26
         MONTHLY AVERAGE:  $   164.11
         SULPHURIC ACID USED -  1986
         TOTAL POUNDS:
         TOTAL COST:
   10,500
$ 1,139.25
                   120

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JANUARY
FEBRUARY
MARCH
APRIL
MAY
JUNE
JULY
AUGUST
SEPTEMBER
OCTOBER
NOVEMBER
DECEMBER
TOTAL
AVERAGE
Total Sludge
DIGESTED SLUDGE
11
141,000
189,000
423,600
643,500
64,800
0
21,000
178,200
97,200
108,000
477,900
216,000
2,560,200
232,745
REMDVED - 1986
#2
198,600
0
0
345,300
246,600
394,200
0
124,200
253,800
151,200
37,800
0
1,751,700
218,963

|3
0
0
0
0
0
140,400
287,400
108,000
129,600
189,000
16,200
0
870,600
145,100
Removed 5,182,500 Gallons
TELEPHONE EXPENSE














1986
January $
February
March
April
May
June
July
August
September
October
November
December
TOTAL $

259.02
220.80
213.70
206.66
238.51
192.44
209.17
210.77
238.46
192.19
187.51
165.36
2,534.59














121

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                           NATURAL GAS
 January
 February
 March
 April
 May
 June
 July
 August
 September
 October
 November
 December
 TOTAL  •
AVERAGE
IRCHASED -
BTO/CF
0.990
0.995
1.006
1.008
1.011
1.002
1.001
1.004
1.009
1.007
1.015
1.015
12.063
1.005
1986
_$/HCF
$ 0.5240
0.5352
0.5416
0.5302
0.5396
0.5229
0.5209
0.5236
0.5242
0.5183
0.5000
0.4978
$ 6.2783
$ 0.5232

1
COST
§ 4,445.65
4,6^3.11
3,380.41
2,985.86
307.59
1,279.52
1,558.59
1,023.21
1,449.44
1,316.47
1,348.68
2,699.00
$ 26,427.53
$ 2,202,29
                                    122

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          KIEL OIL USAGE - 1986*
 DECEMBER 31, 1985   1,000 gallons on hand

      TOTAL GALLONS:        11  955
      MONTHLY AVERAGE:
      TOTAL COST:        5 8,683.95
      MONTHLY AVERAGE:   $ 1,736.79
 * Fuel oil boilers removed  from service, & are
   being  fired by natural gas.
       DIESEL FUEL USAGE - 1986
DECEMBER 31, 1985    400 gallons on hand

     TOTAL GALLONS:         4 262
     MONTHLY AVERAGE:         '355

     TOTAL COST:        $ 2,793.22
     MONTHLY AVERAGE:   $  232.77
        GASOLINE USED - 1986
    REGULAR GASOLINE
    TOTAL GALLONS:       1,775 0
    MONTHLY AVERAGE:       148 0
    TOTAL COST:       $ 1,467.37
    MONTHLY AVERAGE:  $   122.28

    UNLEADEAD GASOLINE (May-Dec)
    TOTAL GALLONS:153.7
    MONTHLY AVERAGE:       19  2
    TOTAL COST:        $    125." 63
    MONTHLY AVERAGE:  $     15.70
           "123

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      MAJOR INDUSTRIAL DISCHARGES  1986 (. 1987 AVERAGES              j

                                      1986                          i 1987
     TMTH1CTDV               _
     J.WJUSIKI               FLOU (H3D)   BOD (bK/L)
                                                                         BCD
                                                             .0039         2530
  3.  Oakland specialities i            ^               "9   :      ^
  4.  Dorman's Cheese        .0103        1597               Q132   •      13?2
  a.  Erito-lay inc.          .0347        2478               0373
                             :0°S        «7S
                             -0407        2602
  o.            ese           :0°}g
                                          }S               -S
 13.  Pleasant Vie,-           .0236         245            .   '££
 14.  Roy's Butter            .0008         396
396               .ooo     :      219
                             .
15.  Swiss Colony - East     .0048        4424                0066
16.  Swiss Colony - West     .0055        1233                0056
17.  Wheel of Swiss*         .0079        2571
                            .
10*  Si™'8 InC'*            -°105        30"               -0103
19.  Monroe Drum & Barrel**                                 nnro
20.  Wisconsin Biotas                                     • ;JJJJ

*Became Zim's on 5/18/86.                                    "           "
** One quarter data in 1987.               '                          |
                                124

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"W
JAN
FEB
MARCH
APRIL
MAY
JUNE
JULY
AUGUST
SEPT
OCT
NOV
DEC
TOTAL
AVERAGE
$
i
ELECTRICAL POWER PURCHASED - 1984 i
pnij-pp
ON PEAK OFF PEAK KWH FACTOR S TOP ^
	 • 	 	 rm.iun ? KHH . COST
37 " 2°6'700 87 0.043 ? 8,9^17
« 56 192,600 86 0.043 8,296.19
43 5? 186'600 So 0.043 7,957.48
" " 219-°°° 86 0.045 9.880.85
42 58 278'400 86 0.042 11,732.45
" 58 293'700 86 0.042 12,274.85
40 6° 316'8°° 86 0.042 13,169.49
44 56 31°'800 87 0.040 121,549.17
3 " 3°2'700 86 0.038 11,424.66
40 6° 3°5'700 86 0.041 121500.82
4 " 262'5°° 86 0.041 10,824.99
-41 5? - 258'9°° 87 0.041 10,607 87
' "^ ' "" tf^4^°-°._i°35 0.501 .. $130,137.99
42 58 1T..261'AOO 86 0.040 $10J844.83
1
i
!
i
1
i
1
j
1
1
125

-------
ELECTRICAL POMER PURCHASED - 1985
JAN
FEE
MARCH
APRIL
MAY
JUNE
JULY
AUGUST
SEPT
OCT
NOV
DEC
TOTAL
AVERAGE
40
43
42
43
41
39 '
42
44
38
41
41
41
495
41
60
57
58
57
59
61
58
56
62
59
59
_59_
705
59
268,500
223,500
230,400
249,600
281,100
276,300
282,600
257,700
255,000
207,000
222,300
143,700
2,897,700
^T 241,475
87
86
86
86
86
86
86
86
85
84
83
_ 80
„__ 1021
85
0.040
0.042
0.041
0.041
0.039
0.039
0.039
0.040
0.045
0.049
0.049
0.053
0.517
0.043
? : 10, 699. 23
I 9,306.69
1 9,367.46
;10,332.05
:10,953.47
10,829.25
11,146.60
10,489.09
11,553.17
10,229.06
il,000.20
'7,608.89
$ 123,515.16
-? 10,292.93
           126

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POWER USAGE KWH
ON PEAK OFF PEAK 	
January
February
March
April
June
July
August
September
October
November
December
TOTAL
AVERAGE
39
45
41
44
44
41
43
45
41
45
44
_40
512
43
61
55
59
56
56
59
57
55
59
, 55
56
_60
688
57
144,000
129,600
148,500
151,200
158,400
162,000
152,400
179,400
210,600
203,400
203,400
266,400
2,109,300
ffFr-™~! 	
|[ 175,775
POWER $/KKH
FACTOR 	
78 $0.045
76 0.052
78 0.049
78 0.048
77
77
77
77
76
74
72
76
916
76
0.049
0.048
0.043
0.043
0.042
0.045
0.042
0.040
$0.546
$0.046
! COST
i
$' 6,529.09
! 6,676.32
} 7,245.77
7,266.43
\ 7,719.98
1 7,822.03
I 6,524.01
17,785.69
-8,795.18
. .9,203.45
8,591.53
10,699.26
$' 94/658.74
$ 7,904.90
127

-------