BIOLOGICAL WASTE TREATMENT
        USING. THE BIOLAC SYSTEM

            A TECHNICAL NOTE
             September 1986
             Prepared For:

  U.S. Environmental Protection Agency
 Off ice-, of. Municipal Pollution Control
     Municipal. Facilities Division
          . 401 M Street,, S.W.
        Washington, D.C.,  20460
              Prepared By:

Environmental Resources Management/ Inc.
       .  999 West Chester Pike
   West Chester/ Pennsylvania,-  19382

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                        ACKNOWLEDGMENTS
ERM wishes  to  thank  Charles Morgan of the Parkson  Corporation
(Fort Lauderdale/ Florida) and Carl Janson of Riordan  Mater-
ials/  Haverford/ Pennsylvania*  for their willingness to discuss
the characteristics/ design/  and performance  of  the  BIOLAC
system.

This report  is a technical assessment of the BIOLAC System/
based entirely  on data  obtained from the manufacturer  of  the
BIOLAC system  and on accepted theories of biological treatment.
It was  prepared for  the  Office of Municipal Pollution Control
under contract  number 68-01-7108.  The information  was compiled
to assist  those involved  in  the  innovative  and  alternative
technology program.   This document has not been subjected to the
agency's  peer and administrative  reviews/ and  therefore does  not
necessarily reflect the views of  the agency.

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                        TABLE OP CONTENTS


                                                       Page

I.  Description of Process and Systea Design             1

     A.  Process and Process Options                     1

     B.  Existing and Proposed Installations             6

     C.  Manufacturer's Claims                           6

II.  Evaluation of Design Procedure - Hew
       Construction and Retrofits                        7

     A.  Design Procedure Recommended by the
         Manufacturer/Supplier                           7

     B.  Comments on the Design Procedure                8

III.  Evaluation of Systev Perfornance                   8

      A.  Manufacturer's Claims                          8

      B.  Availability and Suitability of Existing
          Operations Data                                8

IV.  Level of Confidence in the BIOLAC Treatnent
       Concept                                           9

      A.  BIOLAC Process Innovations                     9

      B.  Basis for Assigning a Good Level of
          Confidence                                     9

      C.  Benefits of Strengthening Certain Design
          Parameters Via a Field Test                   10

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I.   Description of Process and Syatea Design

     A.   Process and Procesa Options

BIOLAC is a  complete biological treatment system for municipal
and industrial wastewaters.  BIOLAC/ an acronym for "Biological
Wastewater Treatment System using  Aeration £hains"/ consists of
an  earthen  basin/  or  lagoon/  with  floating  aeration chains
intended  to aerate and mix the wastewater.  Additional aerated or
unaerated polishing lagoons and a final  channel for nutrient
uptake are optional.  The design goal  is direct discharge of
clarified effluent of secondary treatment quality or better   to a
receiving stream.  Some wastewaters  may  require pretreatment or
post-chlorination.  Parkson Corporation/  which markets BIOLAC/
offers two  systems  for  different applications/  as  shown in
Figure 1  and  described below:

BIOLAC-L.  An aerobic/  flow-through system  for the biological
treatment of domestic  wastewater with  organic loadings of  30 to
300 pounds of BOD per day.  In this  system/ wastewater flows from
a first-stage lagoon into a second-stage polishing lagoon with a
quiescent solids  settling  zone at one end/   and  then into an
optional  channel  containing nutrient-removing aquatic plants.
Polishing consists mostly of additional  solids settling.

BIOLAC-R.  An extended aeration/activated sludge system for the
treatment of domestic and/or industrial wastewaters with organic
loadings  of  300  to 30/000 pounds of BOD  per day.   Unlike
BIOLAC-L, BIOLAC-R  features an integral concrete clarifier with
sludge return at the end o'f the first-stage lagoon/ and a sludge
storage  pond with decant to the first-stage lagoon.  The stored
sludge is claimed  to  develop  a  five  to ten  percent solids
content.

There  are notable  differences between the  design/  intended
application  and  performance of BIOLAC-L and  BIOLAC-R.   For
instance/ BIOLAC-L   is  designed to  be a  flow-through system
without  appreciable solids retention  time/  while BIOLAC-R is
designed  to  be an extended aeration system with 20 to 30 days of
solids retention  time.   Also/ while BIOLAC-L is intended for
treatment of domestic  wastewaters with relatively low organic
loading/  BIOLAC-R is intended for domestic  or  industrial waste-
waters of much higher  organic loadings.   In addition/   BIOLAC-R
is capable of removing greater amounts of BOD/  yet maintaining a
lower  biological solids concentration through extended aeration.
In contrast/  BIOLAC-L is capable of  relatively low  BOD  removal
and is designed to  maintain a certain  hydraulic detention  time/
rather than a particular biological  solids  retention time.  The

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  Influent
                      Figure 1
Schematic  of a BIOLAC Treatment System
(Adapted From a Parkson Corporation Product Brochure)   Effluent
                                                    T
                                   c
                                     Optional Oxidation Ditch With Aquatic Plants
      Sludge' Return     ,.—, Sludge Wasting
,r            |_;   :-x
                              Second-Stage Lagoon
                              For Polishing
                                                                                               KEY

                                                                                             _*_}Biolac-R Only

                                                                                                1 - Operations Building
                                                                                                  with Automatic
                                                                                                  Bar Screen
                                                                                                2 - Optional Gnt
                                                                                                  Chamber
                                                                                                3 - Flow Measuring
                                                                                                  Equipment
                                                                                                4 - Centrally Located
                                                                                                  Blowers
                                                                                                5 - Aerated Chains
                                                                                                6 - Floating Overflow
                                                                                              * 7 - Integral Clanfier
                                                                                                  (Concrete)
                                                                                                8 - Sampling  Point
                                                                                                9 - Floating Plaslicized
                                                                                                  Cloth Wall With
                                                                                                  Openings for
                                                                                                  Wastewater Flow
                                                                                             *10 - Sludge Pond
                                                                                                  with Decant Return

                                                                                                  Not To Scale

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manufacturer believes  that  the unique features of  BIOLAC-R are
more  applicable for  meeting  the  more  stringent  discharge
limitations placed on domestic and industrial wastewaters.

Aeration Chains.  Both  the  BIOLAC-L and BIOLAC-R  systems are
equipped with floating "aeration  chains"/ shown in Figure 2, for
mixing and aeration.  Wyss" flexible sheath  diffusers are  sus-
pended  from  the floats  of these  aerated  chains/  which are
anchored to the edge  of  the lagoon by stainless steel cables.

          1.   Design Parameters and Assumptions

BIOLAC  design parameters  are  similar to those  of  conventional
biological systems.   Table  1  compares typical design  criteria for
BIOLAC-L with  conventional flow-through  aerated  lagoons and
BIOLAC-R with extended aeration/activated sludge systems.  Table
1 shows that the BIOLAC-L system design/  like the aerated lagoon/
is based on hydraulic detention time rather  than organic loading
or biomass requirements.  The  six  to fifteen days  of  detention
time recommended for  BIOLAC-L is a somewhat  higher range than the
typical  aerated lagoon detention time of three to ten  days.  In
addition/ BIOLAC's manufacturer predicts  that power requirements
for mixing BIOLAC aeration basins are much  less than the typical
ones  for mixing  conventional  aerated  and extended  aeration
lagoons/ as shown in  Table  1.

The conventional extended  aeration lagoon is designed  for an F:N
ratio of between 0.05 and 0.15 pounds of  BOD  per pound of  MLVSS/
while the  BIOLAC-R system is designed  for a  ratio  of 0.03 to
0.10 in order to minimize sludge  yields.  The  recommended  MLSS
concentration range  is also somewhat lower  for BIOLAC-R than for
the  conventional  system.    The  manufacturer claims   that
nitrification will also   occur  in  the  extended aeration basin
(first stage lagoon).

          2.   Typical Operating Conditions

For the  BIOLAC  aeration  system/  Parkson  suggests  a  minimum
standard oxygen transfer rate of  four to five  pounds  of  oxygen
per horsepower-hour/  a minimum of 0.08 to 0.12 aerator  horsepower
per 1/000 cubic feet  of lagoon volume for mixing/ ten-to  fifty-
foot spacing between aeration chains/  and 9 to 30  inches  of
clearance  for diffusers above  the  bottom of  the lagoon.  Each
float  assembly is  equipped with either two or four Wyss" flexible
sheath diffusers/  each of which   provides one  to five standard
cubic feet  of air per minute.  Four  diffusers could  thus provide
up to  twenty standard cubic  feet  of air per minute.   Aeration
chains are  typically between 30 and  400  feet in length.  The EPA
document/  EPA 625/8-85-010/ indicates that EPA has  studied the
Wyss"  diffusers and classified them as fine bubble diffusers. The

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                                       Figure 2
                  Schematic of a BIOLAC Aerated Chain System
                           Float Assembly
            Hose Clamp
                      D
                                                       Air Pipe
                           •Downcoming Air Tube
•
 •  •
                                   o .
    ••°    •   •• -  °..o
       •  O   ma   a
                                                                  Water Surface
                                                              Two or Four "Wyss" Diffusers
                                                             ' Per Float Assembly
                             9" - 30"
              iw^vt:**^7Viv;;i:^


                                       Float
                                             •*• -^ ^ •*• *• ^
                                                       Water Surface
                                                   "Wyss" Flex-a-Tube
                                                       Flexible Sheath
Not to Scale
                                                          •^:V-r,*^-?.:-?i'--''•'?••'•-'.

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Ul
                                                               TABLE 1

                                           MANUFACTURER'S DESIGN CRITERIA FOR BIOLAC SYSTEMS
                                                IN COMPARISON WITH AERATED LAGOONS AND
                                                  EXTENDED AERATION/ACTIVATED SLUDGE

                                                                     Design Criteria
Parameter
Lagoon Depth/ Feet
Hydraulic Detention Time/ Days
Food: Microorganism Ratio/
Ib. BODs/day/lb. MLVSS
BCD Removal/ %
HLSS, mg/1
Solids Retention Tine (SRT) days
Effluent TSS, mg/1
Aeration Basin Mixing Require-
ment (HP/MG of basin volume)*1'
Aerated Lagoon*
6 to 20
3 to 10
Not Applicable
80 to 95%
NR
3 to 6
260 to 300
70 to 130<2)
Biolac-L**(l)
8 to 20
6 to 15
Not Applicable
90% / typically
NR
NR
NR
3-6 HP/MG
(Typical)
Extended Aeration/*
Activated Sludge
Not Applicable
.75 to 1.5
0.05 to 0.15
75 to 95%
3/000 to 6/000
20 to 30
20 to 30
130 to 200<2>
Biolac-R**(l)
8 to 20
1 to 2
0.03 to 0.10
99%, typical 1]
1,500 to 5,00(
50 to 70
NR
12 to 15 HP/MC
    Sludge Recycle Ratio
Not Applicable
Not Applicable
0.75 to 1.50
Adjustable
    NR:  Not Reported
    *  Reference:  MeteaIf and Eddy/ Inc., Wastewater Engineering, 1972.
    ** Reference:  Parkson Corporation

    1 Data from manufacturer, Parkson Corporation
    2 Horsepower required for mixing, which is typically greater than that for oxygen demand in  the  systems noted.

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EPA  report  does not indicate/ however/  that the Wyss" diffusers
meet the ASCE criteria for  fine  bubble  diffusers.  When  fully
charged  with  air/  the  manufacturer notes/  the  air bubbles
approach medium size.

          3.   Major Equipment

BIOLAC-L  and BIOLAC-R systems both require air blowers/ aeration
system controls/  influent and effluent  pumps/ and overflow  weirs.
Temperature and pH recorders are  optional.   BIOLAC-R also  re-
quires an integral clarifier/ a sludge  airlift pump and possibly
a sludge  wasting pump.   Lagoon  liners  may  be  required to meet
environmental requirements.

     B.   Existing and Proposed Installations

Of the 100  BIOLAC  systems operating in  Europe/  performance data
are  available for  only  three:   BIOLAC-R systems  located  in
Konigslutter,  Rot  am  See/ and Bielefeld/ West  Germany.  At  ten
sites/  substitution of existing aeration systems with aeration
chains (a type  of retrofit) has occurred.  Site locations include
Franklin/ Ohio/  and Pierrepont  Manor/  New York.  Eight  other
retrofits are  planned for  installation/ are currently  being
installed/  or  are in a  start-up  phase for the  treatment  of
domestic/ poultry/  industrial wastewater in the United States.
One BIOLAC-R project has been granted  funding under the  EPA's
Innovative/Alternative Program.  It will be located in Columbiana/
Alabama (EPA Region IV).

     C.   Manufacturer's Claims

According  to the  Parkson Corporation/  the BIOLAC  system  is
applicable to any biodegradable wastewater and incorporates many
proven treatment processes in a  highly  efficient and innovative
way.   Presently/  German  BIOLAC  installations  treat  food and
beverage  industry  as  well as domestic  wastewaters with organic
loadings  ranging from 40 to 22/000 pounds per day  of BOD and flow
rates  ranging  from  0.01  to 1.6 NGD.   In comparison with conven-
tional  extended aeration/activated sludge systems/  the BIOLAC
system is claimed  to  have greater system stability/  equal  or
better BOD  removal  capability/ reduced sludge  production and
greater nitrification  (BIOLAC-R only)/ and lower construction!
operating/ and  maintenance costs.   The manufacturer attributes
these  benefits  to  the  longer design SRT used.   Major advantages
cited  are  the  efficient  use  of  submerged/  flexible sheath
diffusers/  earthen  lagoons/  and  the system's ability to perform
at low  organic  loading rates and in cold  climates.

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 II-  Evaluation of  Design  Procedure  -  Hew Construction and
     Retrofita                                                 '

     A.-   Design  Procedure  Recoanended  by the  Manufacturer/
          Supplier

 Information on specific procedures used  in the design of  existing
 plants was not available.   However/ the  manufacturer recommends a
 design based on conventional  parameters  (source/  quality  and  flow
 rate of wastewater/  the desired effluent quality) and the design
 criteria  indicated in  Table 1.   A treatability study is  recom-
 mended  prior to design/  particularly  for wastewaters with a
 significant industrial  component/ in order to optimize the  system
 design.  Following  system  installation/  the  manufacturer empha-
 sizes  the need  to  monitor  the  lagoons for dissolved  oxygen/
 temperature/ and pH/  as is advisable with any aerobic treatment
 system.   However/  the  manufacturer believes that less monitoring
 effort is needed than with conventional  systems.

 Generally/  for domestic  wastewaters at less than 200/000 gpd a
 BIOLAC-L system is  recommended/ while BIOLAC-R is recommended for
 higher  municipal flows and  industrial wastewaters. Each waste-
 water should be evaluated  for selection  of the type of system to
 be applied. To provide extended aeration and  desired  effluent
 quality/ BIOLAC-R lagoons  are designed to provide specific  ranges
 for  hydraulic retention  time/  food to microorganism ratio/ and
 NLSS.  The BIOLAC-R sludge storage pond is  typically  sized to
 provide at  least six months  of storage  to allow  stored sludge to
 dewater to a predicted  five to ten percent solids.

 Parkson does not provide'specifics on retrofitting an  existing
 lagoon/  but indicates that performance data  for  the lagoon will
 determine  whether its  size  is adequate for the intended  treat-
 ment.  The manufacturer  claims that a conventional  lagoon can be
 modified to resemble a  BIOLAC  system.

 Replacement of existing  surface aerators or fixed diffusers with
aerated chains  is recommended to improve mixing/ lessen  aeration
 energy requirements  (versus surface aerators and  coarse bubble
diffusers)/  simplify maintenance and reduce maintenance costs.

For  both  new construction and  retrofits/  the aeration  chain
 system  is  designed according to the selected lagoon depth/ the
wastewater quality and  flow rate/  seasonal temperature  fluctua-
 tions/ and  the  oxygen demand  of the wastewater.  The required air
discharge  pressure and  blower  capacity are determined from this
 information  and  the design  of  the Wyss1" diffusers.

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The manufacturer claims  that the aeration chains  provide adequate
mixing at much less energy  than that required for aeration and/
therefore/   the  aeration system  design is controlled  by the
aeration requirements.   This contrasts  with  the practice  of
sizing  conventional  lagoon  aeration  systems  on the  basis  of
mixing requirements.

The manufacturer recommends that the second lagoon be installed
in every BIOLAC system in order to provide additional  buffering
capacity for  handling  peaks in  organic  concentrations and
hydraulic loads.  The  buffer is intended to reduce the  level  of
operator attention required.

     B.   CoMDenta on  the Design Procedure

Since BIOLAC systems utilize conventional treatment processes and
are designed on  the  basis of well-established principles  of
biological  treatment/  their design  procedure  is  correct  in
theory.   However/ since specific  documentation on the  design
procedures  is  not available/  further information is necessary  to
verify the basis of the  design.  The use of submerged diffusers
should  reduce  drops in lagoon temperature.   It  is not clear how
much  benefit  is  provided by  the  second aeration  lagoon  in
BIOLAC-R/ since about 95 percent of the treatment occurs in the
extended aeration  lagoon.

III.  Evaluation of System Performance

     A.   Manufacturer'a Claina

No opportunity  was available to compare  the manufacturer's claims
with  reports  from actual BIOLAC  operators  in Europe.   The
manufacturer  feels that the wide  application  of the BIOLAC  in
Europe  attests to its high  performance.   In  addition/ two
BIOLAC-R and  ten individual aeration  chain systems have  been
sold/  and will  begin operating by  mid-1987.

     B.    Availability and Suitability of Existing Operations
          Data

More design  and operational data are needed to fully evaluate the
BIOLAC  treatment  concept.   For  example/  only  limited  case
histories from three  West German BIOLAC-R plants are available/
although they show high BOD removals and represent a wide  range
of influent  flows.  None of the available operations data pertain
to BIOLAC-L  plants/ and none include percent  removals of suspend-
ed solids/ the  degree of dewatering  in the sludge settling ponds/
or performance  during  an entire  winter or over the long  term.

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Only  one  case history provided  data for nitrification and COD
removals.   Furthermore/ only a limited amount  of design data (BOD
loadings  and population equivalents) are available for comparing
specific BIOLAC designs to actual plant construction and perform-
ance.

IV.  Level of Confidence in the BIOLAC TreatBent Concept

      A.   BIOLAC Process Innovations

The  BIOLAC system employs  several  unproven design  features.
These include:

     1.   The efficient use  of  submerged  flexible  sheath
          diffusers  in a  large  volume/  earthen  lagoon
          system/ which  is  predicted to  increase  oxygen
          transfer efficiency and reduces capital cost;

     2.   The  use of  low  F:M  ratios  and longer  solids
          retention times in an economical system  (relative
          to lagoons  with conventional aeration systems)/
          to produce a  low-volume/ well-stabilized  sludge
          and  to achieve  process  stability/  high  BOD
          removal/ and nitrification;

     3.   The use of integral clarifiers to reduce construc-
          tion costs (BIOLAC-R only); and

     4.   The  use of  "aeration  chains"  to  "sweep"  the
          lagoon/  reducing the mixing horsepower  require-
          ments.        '  '

Critical  design  variables for BIOLAC are  solids retention time/
hydraulic  detention time/ organic  loading/ and aeration  horse-
power requirements.

     B. Basis for Assigning a Good Level of Confidence

ERN can assign a good level of  confidence to the theory of the
BIOLAC concept for  the treatment  of wastewater in  the  United
States.   However/ due to incomplete design and operational data/
and the fact that as of September 1986,  there are no operational
non-retrofit BIOLAC  installations  in the United States/ use  of
theBIOLAC system would carry  "relatively high technological
risk"  according to guidelines  issued by  EPA.   Therefore the
BIOLAC system would  fall under  "Area A: Field Test  to  Verify
Design for Innovative Designation/" of Figure 1:  Window of Risk/
as shown in the "Guidance on  Designating Projects as Innovative,"
(USEPA/ Office of  Municipal Pollution Control).  The  recent EPA
grant  for  a  BIOLAC-R  system in Alabama  may serve as this field

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test.   If  so/  successful operation  of this BIOLAC-R may allow
BIOLAC to be later designated as having the  potential for further
designation as  Innovative.  However/  the fact  that there are over
100 operating systems in Europe is a  very strong  indication that
the  system  could  have successful  application in the  United
States.  In addition/ two complete BIOLAC-R and ten individual
aeration  chain systems are scheduled for  start-up in mid-1987.
Furthermore/ no new  treatment theories are apparently used in the
BIOLAC  design;  all  components of the  BIOLAC system  appear to be
designed  on the basis  of  accepted/  conventional theories  of
biological treatment.

No final  conclusion about the performance  of the aeration chain
systems can be made.   The manufacturer reports no mechanical
failures  to date but  recommends an  annual  inspection of  the
aeration system.

     C.  Benefits of Strengthening Certain Parameters Via a
          Field Teat

Field  tests would  improve BIOLAC design guidelines for similat
treatment  applications/ and thereby increase the  probability that
such a  system  would perform well and not require additional
expenditures for system modifications.   Design criteria could  be
strengthened for particular wastewater types and climates/  and
the system components could be sized  more accurately.
                               10

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