EPA-R2-73-147
JUNE 1973                 Environmental Protection Technology Series
     Biological  Removal of
     Colloidal Matter  from Wastewater


                                    Office of Research and Monitoring

                                    U.S. Environmental Protection Agency

                                    Washington, D.C. 20460

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            RESEARCH REPORTING SERIES
Research reports of the  Office  of  Research  and
Monitoring,  Environmental Protection Agency, have
been grouped into five series.  These  five  broad
categories  were established to facilitate further
development  and  application   of   environmental
technology.   Elimination  of traditional grouping
was  consciously  planned  to  foster   technology
transfer   and  a  maximum  interface  in  related
fields.  The five series are:

   1,  Environmental Health Effects Research
   2.  Environmental Protection Technology
   3.  Ecological Research
   4.  Environmental Monitoring
   5.  Socioeconomic Environmental studies

This report has been assigned to the ENVIRONMENTAL
PROTECTION   TECHNOLOGY   series.    This   series
describes   research   performed  to  develop  and
demonstrate   instrumentation,    equipment    and
methodology  to  repair  or  prevent environmental
degradation from point and  non-point  sources  of
pollution.  This work provides the new or improved
technology  required for the control and'treatment
of pollution sources to meet environmental quality
standards.

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                                                    EPA-R2-73-147
                                                    June 1973
    BIODOGICAL REMOVAL OF COLLOIDAL MATTER

                      FROM

                   WASTEWATER
                Walter J. Maier
            University of Minnesota
         Minneapolis, ffitBaabota  55455
                Grant #17030 DGQ
             Program Element 1B2043
                Project Officer

                Robert L. Bunch
     U.S. Environmental Protection Agency
    National Environmental Research Center
             Cincinnati, Ohio  ^5268
                     for the

      OFFICE  OF RESEARCH AND MONITORING
    U.S. ENVIRONMENTAL PROTECTION AGENCY
            WASHINGTON, D.C. 20k60
For sale by the Superintondenfolflipijilli'ff.&^JJoyermnent Printing Office, Washington, D.O. 20402
                                ! OPO Bookstore

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          EPA Review Notice
This report has been reviewed by the
Office of Research and Monitoring, EPA,
and approved for publication.  Approval
does not signify that the contents
necessarily reflect the views and
policies of the Environmental Protection
Agency, nor does mention of trade names
or commercial products constitute endorse-
ment or recommendation for use.

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                          ABSTRACT
This research program was designed to provide a more basic under-
standing of the mechanism and rates of removal of organic materials
from waste waters by biological processes.  Pure compound feed
materials were used with the exception of a series of tests on
sewage solids obtained from the Minneapolis-St. Paul Sewage Treat-
ment Plant by centrifugation of'primary effluent.  Two model reactor
systems were used to measure rates of substrate removal.  The film
flow reactor, characterized by a stationary biological slime layer,
was used to study removal kinetics under conditions where mass trans-
fer may be a limiting factor.  A well mixed batch reactor was used
to study rates of removal under conditions where biological processes
are rate controlling.  Rates of substrate degradation and carbon
removal are reported for each of the pure - compounds using acclimated
innoculum.  Rate data from batch reactors are expressed in terms of
microbial growth rate coefficients.  Rate data from the film flow
reactor is reported as the quantity of substrate removed per unit
of slime surface per unit of time.

This report was submitted by the University of Minnesota, Minneapolis,
Minnesota  55455, in fulfillment of Project No. 17030 DGQ under the
sponsorship of the Environmental Protection Agency.
                            iii

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                           CONTENTS

                                          \

                   SUMMARY AND  CONCLUSIONS


                        INTRODUCTION
Mechanisms and Controls of Biological Degradation           5
Colloidal Substrates - Physical Characteristics              6
Metabolism of Colloidal Substrates                           7
Kinetics - Growth and Enzymes                                8
Mathematical Analysis of Film Plow Reactor                  11
Waste Water Composition                                     16
            APPARATUS AND EXPERIMENTAL PROCEDURE            18
Batch Reactor                                               18
Film Plow Reactor                                           18
Continuous Propagator                                       21
Peed Solutions                                              21
Analytical Procedures                                       22
                 BATCH REACTOR TEST RESULTS                 23
 Chemistry of Starch                                         23
 Characterization of Starch                                  24
 Molecular Weights of Starches                               25
 Sephadex Gel Separation of Starches                         25
Hydrolytic Degradation of Starch                            29
 Comparison of Biological Degradation of Different  Starches 32
 Soluble Exoenzyme Activity                                  37
 Degradation of Starch-Glucose Mixtures                      39
 Amlno Acid Metabolism                                       42
 Glutamic Acid Utilization                                   45
 Glycene Utilization                                         48
 Protein Chemistry                                           48
 Protein Degradation                                         51
 Milk Solids                                                 54
 Lipid Chemistry                                             58
 Fatty Acid Degradation                                      60
 Rate Studies Using Treatment Plant Biomass                  68
 Measurement of the Rate of Oxygen Uptake of Sewage Solids   74
                              iv

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               FILM BLOW REACTOR 1EST RESULTS              ?8
Mass Transfer Considerations in Biological Treatment       78
Biological Treatment                                       78
Biological Slime Layer                                     79
Film Flow Reactor-Operating;Procedure                      81
Starch Degradation                                         81
Glucose-Starcli Mixtures                                    85
Amino Acids and Proteins                                   86
Laurie Acid                                                89
Mixed Feed Acclimated Slime Surface                        91
Discussion - Summary of Film Flow Reactor Results          9^

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                           FIGURES


No.


                        INTRODUCTION
1         Schematic Diagram of Control Volume              12
2         Normalized Solution Equation 20                  15
             PART A - APPARATUS AND EXPERIMENTAL
                          PROCEDURE
          Film Flow Reactor                                20


             PART B - BATCH REACTOR TEST RESULTS
4         Sephadex Gel Separation of Soluble Starch        27
5         Sephadex Gel Separation of Starch SD-5           28
6         Hydrolytic Degradation-Effect of Starch
          Concentration                                    30
7         Rate of Degradation of Starch                    31
8         Biological Degradation of Starches               33
9         Biological Degradation of Starches               34
10        Biological Incorporation of Starches-Removal
          of Carbon                                        36
11        Soluble Exoenzyme Activity                       38
12        Degradation of Starch-Glucose Mixtures           40
13        Degradation of Glucose from Starch Glucose
          Mixture                                          111
14        Biological Degradation of Glutamic Acid-Effect
          of Concentration                                 46
15        Biological Degradation of Glutamic Acid-Rate
          of Carbon Removal-Effect of Concentration        47
16        Glycine Removal in Acclimated Innoculum          49
17        Amino Acid Degradation with Glycine Acclimated
          Innoculum                                        50
18        Protein Carbon Utilization Using Mixed Feeds     53
19        Biological Degradation of Milk Solids            56
20        Milk Solids Carbon Utilization Rates             57
21        Fatty Acid Degradation-Carbon Removal            62
22        Degradation of Mixed Feed Solution by Laurate
          Acclimated Innoculum                             63
23        Removal of Glutamate and Glucose by Laurate
          Acclimated Innoculum                             64
                             vi

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No.
24        Mixed Peed Innoculum-Carbon Removal              66
25        Mixed Feed Innoculum-Glucose and Glutamate
          Removal                                          67
26        Glucose Removal by Activated Sludge Biomass      70
27        Amino Acid Removal by Activated Sludge Biomass   71
28        Starch Removal by Activated Sludge Biomass       72
29        Protein Removal by Activated Sludge Biomass      73
30        Op Uptake Rate of Activated Sludge Using
          Sewage Solids                                    76
31        Carbon Concentration of Sewage Solids            77
           PART C - FILM FLOW REACTOR TEST RESULTS
32        Starch Concentration Versus Flow Rate            83
33        Starch Degradation Versus Feed Concentration     84
34        Glutamic Acid-Carbon Removal                     87
35        Laurie Acid-Carbon Removal                       90
36        Skim Milk Solids Removal                         93
                             vii

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                   LIST OP APPENDIX TABLES
        Title
Experiment No.
Page
Effect of Starch Concentration on         4-2-68
fetes of Biological Decomposition

Part I - Comparison of Biological         4-30-68
Decomposition fetes of Different
Starches.

Part II - Comparison of Biological        5-7-68
Decomposition Rates of Different
Starches.
Test for "Soluble" Exo-enzyme
Activity - Part I

Test for "Soluble" Exo-enzyme
Activity - Part II

Biological Decomposition of Starch
Glucose Mixtures

Effect of Glutamic Acid Concentra-
tion on Rate of Biological Decomp-
osition
Effect of Glutamic Acid Concentra-        2-5-69
tion on Rate of Biological Decomp-
osition

Glycene Degradation by Glutamic .          2-20-69'
Acid Acclimated Innoculum

Protein and Glutamic Acid Degrada-        3-12-69
tion on Glutamate Acclimated In-
noculum

Effect of Concentration on Biological     3-18-69
Degradation of Peptone and Glutamic ,•
Acid using a Peptone Acclimated Culture
                     95


                     98



                    100
2-9-68
2-10-68
8-29-68
12-20-68
101
102
104
107
                    109



                    111


                    113


                    116
                           viii

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List of Appendix Tables Cont.


          Title                         Experiment No.      Pag
Biological Degradation of Glu-            3-20-69           119
tamate, Glycine and Peptone using
Glutamate Acclimated Innoculum

Determination of Carbon Residues          6-19-69           122
from Glutamic Acid Metabolism

Effect of Milk Solids Concentra-          8-12-69           125
tion on Rate of Decomposition

Biological Degradation of Milk            8-18-69           127
Solids with Different Amounts of
Biologically Active Solids

Effect of Substrate Concentration         9-22-69          ,129
for Glycene Acclimated Innoculum

Effect of Substrate Concentration         10-7-69           132
in Degradation of Laurie Acid

Effect of Substrate Concentration         12-18-69          133
in Degradation of Laurie and Pal-
mitic Acid

Effect of Substrate Concentration         12-23-69          136
on Degradation of Palmitic and
Laurie Acid

Effect of Substrate Concentration         12-30-69          139
on Rate of Degradation of Mixed
Peed Solutions

Effect of Substrate Concentrations     •   1-29-70           141
on Rate of Degradation of Mixed
Peed Solutions

Effect of Substrate Concentration on      2-23-70      '     144
Rate of Degradation of Mixed Feed
Solutions
                              Ix

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List of "Cables Cont.
        Title
Effect of Substrate Concentration on
Rate of Degradation of Mixed Peed

Effect of Substrate Concentration on
Rate of Degradation of Mixed Peed

Effect of Substrate Concentration on
Rate of Degradation Using Mixed Peed
and Excess Ammonia Nitrogen

Effect of Substrate Concentration on
Rate of Degradation Using Mixed Feed
and Excess Ammonia Nitrogen

Effect of Substrate Type on Rate
of Degradation Using Mixed Liquor
Activated Sludge from Minneapolis-
St. Paul Sewage Treatment Plant

Effect of Substrate Type on Rate
of Degradation using Mixed Liquor
Activated Sludge from Minneapolis-
St. Paul Sewage Treatment Plant

Effect of Milk Solids Concentration
on Rate of Biological Degradation
in a Film Plow Reactor

Effect of Milk Solids Concentration
on Rate of Biological Degradation
in a Film Flow Reactor

Effect of Laurie Acid Concentration
and Mixed Feed Solutions on Rate of
Biological Degradation in a Film
Flow Reactor
Experiment No,


  4-30-70


  5-21-70


  6-19-70



  7-15-70



  7-23-70
  8-11-70
  8-20-69
  9-4-69
  3-17-70
Page


147


149


151



153



155
157
160
161
162
                             X

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List of Tables cont.
        Title                           Experiment No.      Pag
Effect of Flow Rate on Biological         4-9-70            164
Degradation of Mixed Feeds in a
Film Flow Reactor

Evaluation of Mixed Feed Solutions at     8-20-70           165
various Flow Rates in a Film Reactor

Evaluation of Starch, Protein and         8-29-70           166
Laurie Acid Feed Mixtures in a
Film Reactor
                              XI

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SUMMARY

This research program was designed to provide a more basic understand-
ing of the mechanism and rates of removal of organic materials from
waste waters by biological processes.  Such information is needed to
develop fundamentally sound process variables correlations and to
stimulate development of new design concepts or process improvements
of existing biological treatment devices.

Typical municipal waste waters contain a wide variety of organic
materials; the major categories of biological compounds are represented;
colloidal materials include carbohydrates, proteins, and lipids; soluble
constituents include sugars, amino acids, and fatty acids.  Soluble
constituents typically account for less than 25 wt.$ of the organic
fraction.  It follows that degradation of colloidal and larger partic-
ulates is a crucial, if not controlling factor, in biological treatment.

Pure compound feed materials were used with the exception of a series
of tests on sewage solids obtained from the Minneapolis-St. Paul Sewage
Treatment Plant by centrifugation of primary effluent.  Starch and
glucose were used as representative carbohydrates; peptone, glutamate,
and glycine were used as representative protein related materials and
palmitate and laurate were used as representative lipids.  Each sub-
strate was tested individually and in admixture with other substrates
to test for Interactions.  Two model reactor systems were used to
measure rates of substrate removal.  The film flow reactor, character-
ized by a stationary biological slime layer, was used to study removal
kinetics under conditions where mass transfer may be a limiting factor.
A well mixed batch reactor was used to study rates of removal under
conditions where biological processes are rate controlling; the well
mixed batch reactor approximates process conditions encountered in
completely mixed activated sludge type treatment devices.  Biological-
ly active sludge (innoculum) was obtained from continuous propagators,
starting with sludge obtained from the Mlnneapolis-St. Paul Sewage
Treatment Plant.  In the film flow reactor, liquid medium flows over
a stationary slime layer in a thin film.  Flow is parallel to the
slime surface so that direct contact between feed solution and cell
mass is limited to the interface.  Mass transfer of the substrate to
the biologically active slime surface is slow, primarily by molecular
diffusion; the film flow reactor simulates some conditions encountered
in trickling filter processes.

Rates of substrate degradation and carbon removal are reported for
each of the pure compounds using acclimated innoculum.  Rate data
from batch reactors are expressed in terms of microbial growth rate
coefficients; pure compound substrates show growth rates in the range
0.005-0.010 per minute on acclimated innoculum.  The rates of degrada-
tion of colloidal, substrates cover a broader range, presumably because
hydrolytic cleavage, which is mediated by exoenzymes, precedes the
final utilization of the substrate, and may be a limiting factor if

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 the microbial population is not acclimated to the colloidal substrate.
 Data,  usdng  starch substrates, show that enzyme activity decreases as
 the reaction proceeds.  It appears that the hydrolytic exoenzymes are
 inhibited by the products of hydrolysis; products of hydrolysis act as
 competitive  inhibitors as evidenced by the increase in the calculated
 values of Michealis-Menton adsorption coefficients.

 Substrate uptake of slime surfaces acclimated to single substrates
 seem   to  be  mass transfer limited at concentrations below 100 mg/1 and
 reaction  limited at higher concentrations.  Rate data from the film flow
 reactor are  reported as the quantity of substrate removed per unit of
 slime  surface per unit of time, (mg/cm -min}.  Maximum uptake with sin-
 gle substrates is in the range 50-250 x 10~  mg/cm -min.  Highest rates
 were observed with lauric acid, glucose, and when mixed substrates
 were used.   Lowest uptake rates,-were observed with starch feed; starch-
 carbon uptake was only 50 x 10  mg/cm -min. even though the rate of
 starch degradation was 2-4 fold greater.  By contrast, protein removal
 and carbon disappearance are more nearly equivalent.  Both starch and
 protein molecules are far too large to be absorbed directly into
 bacterial cells, leading to the conclusion that ezoenzymes, either
 free or bound to the cell surface, are responsible for the hydrolytic
 breakdown of colloids, followed by ingestion of soluble fragments.
 The starch-carbon data suggest that the sites for hydrolysis and in-
 gestion are  independent and physically separated, as evidenced by the
 low carbon uptake rate.

 Acclimation  of the slime surface is necessary when new substrates are
 introduced;  glucose is an exception.  Acclimated surfaces may loose
 their  activity for metabolizing a given substrate if the substrate is
 removed for  any appreciable time, (a matter of hours).  Acclimation of
 the surface  to an entirely new substrate may take several days.  It
 appears that an entirely different surface coating (different bacterial
 species)  is  formed.

 Use of mixed substrates generally results in higher rates of carbon
 uptake.   This is particularly pronounced when carbohydrates are added.
 Preferential utilization of glucose In pure compound mixtures and lac-
 tose from skim milk substrated have been observed.  Nevertheless, there
 is concurrent utilization of other substrated e.g. protein and starch
 degradation  as well as some uptake of carbon from noncarbohydrate
 sources.

 The results  of this study provide- new insight on the behavior of bio-.
 logically active slime layers and provide quantitative information on
 rates  of degradation of the major biochemical constituents of waste
water.   The  results have been used to guide pilot plant test programs
 sponsored by the University of Minnesota for the development of more
 fundamentally based engineering design correlations.  A three vessel
prototype activated sludge unit with sludge recycle was used to study
 the effects  of residence time and substrate concentration using the

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same types of feed substrate mixtures as used in the model reactor test
program.  The results will be published in the near future.

Data from the film flow reactor  indicate that mass transfer may be the
rate limiting factor at low substrate concentrations.  This suggests
that some commonly used operating modes for trickling filters may not
be sound  and should be  reconsidered.  For example, the use of effluent
recirculation would appear to be undesirable at low BOD concentrations
because removal may well be mass transfer limited.  The use of packing
which minimizes liquid  hold up seems undesirable in a mass transfer
limited reactor.  It is therefore recommended that trickling filter
plant tests be carried  out to determine the effects of these process
variables under closely controlled  conditions.  In view of the high
potential rates of biological activity that are associated with the fix-
ed slime  layer, further work is  recommended to delineate optimal condi-
tions leading to  new design of packing as well as the use of movable
surfaces.
 INTRODUCTION

 Biological degradation of waste  matter is  a naturally occurring pro-
 cess,  albeit a slow one,  which functions in all  receiving waters such
 as  lakes and rivers.   However, the  capacity of this natural process of
 purification is limited.   Overloading of receiving waters results in
 gross  pollution and makes waters undesirable  for reuse.  To avoid this
 situation, treatment of wastewaters prior  to  discharge becomes increas-
 ingly  important.  In fact, progressively more treatment will be requir-
 ed  in  the future in order to keep pace with the  rapidly increasing
 quantities of wastes being disposed.

 Man-made treatment devices such  as  activated  sludge units and trickling
 filters  essentially are modifications of the  naturally occurring process-
 es.  The same biological  phenomenon of microbial metabolism underlies
 the removal of waste materials.   Man-made  devices  differ from the nat-
 urally occurring purification process in that they are designed for
 relatively short detention times in order  to  make  them economically
 feasible.   However, increasing the. degree  of  treatment as measured by
 the percentage removal of waste  matter requires  longer detention times
 and increases the costs markedly.  The cost increases exponentially
 with percent removal.   It follows that the increasing need for more
 complete treatment of wastewaters which is  projected for the future
 will stimulate a search for  cost  reduction in the design of treatment
 facilities.

Design of conventional treatment facilities is based on an impressive
 accumulation of many years of practical experience.  Within the context
 of  these correlations,  many process design improvements have been devel-
 oped and cost reductions  achieved.  However,  it  seems unlikely that

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any major design Improvements or cost reduction for convential treat-
ment facilities will be forthcoming from this approach in the future.

An alternate approach is to develop a more fundamental understanding
of the underlying principles of biological treatment in the hope of
arriving at new design concepts or uncovering new ideas.

To this end, there is need for descriptions of the mechanism of biologi-
cal purification at the microscopic and/or molecular level.  Description
at the microscopic level must consider such factors as:

               Size and composition of the waste material, e.g., sol-
          utes and colloids, carbohydrates, proteins, and lipids.

               Characterization of the microorganism population and
          its physical distribution, e.g., predominant bacterial specie:;,
          mobility relative to the solution, dispersion of cells.'

               A measure of the rates of metabolism.

               A measure of the effectiveness of mass transfer of war;te
          matter to the cells.

It obviously is impossible to study the effects of all variables in one
set of experiments.  Meaningful results can be obtained only by varying
a limited number of variables at one time while holding other conditions
constant.

With this in mind, a broad-based model study has been carried out using
a variety of soluble and collodial pure compound organic materials.
The materials where chosen with a view to approximating the types of
organic material that are found in municipal and industrial wastes.

The use of model reactors and pure compound substrates allows studying
complex systems under controlled conditions.  The models do not dup-
licate all aspects of the reaction system, but are designed to isolate
process variable effects.  This provides a more theoretical basis for
correlating process results, and leads to a better understanding of
the mechanisms of biological treatment.

The broad objective of this study was to Investigate the biologically
mediated removal of organic matter from a mechanistic standpoint in
order to provide a better understanding of the overall process.  Such
information is needed.to develop fundamentally sound process variable
correlations and rate equations.

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MECHANISMS AMD CONTROLS OF BIOLOGICAL DEGRADATION

Biological treatment for the removal of organics from water comprises
a sequence of interrelated steps including mass transfer, adsorption
and a host of biochemical reactions.  Considering the microbial cell as
the center of this activity, the sequence starts when dissolved, or
colloidal organics, salts, and oxygen from the bulk liquid phase are
transported to the surface of the bacterial cell.  Mass transfer is by
molecular diffusion and by eddy current transport.  At the cell surface,
utilization proceeds with adsorption and.ingestion of the nutrients
necessary for growth, followed by step-wise oxidation within the cell
to provide energy and building blocks for growth.  By-products and oxi-
dation products are released into the bulk liquid phase.

Two limiting situations suggest themselves—the case where mass trans-
fer limits the rate of removal, and the case where cell metabolism limits
the rate of utilization.  Process variable, effects will be different for
these two situations because mass transfer and cell metabolism are known
to respond differently to changes of such process variables as mixing,
nutrient concentration, and temperature.  By studlng these limiting
situations it is possible to learn a great deal about the mechanisms
which control the overall process of removal of waste matter by bio-
logical means,

Two model reaction systems were used to simulate the above situations.
A well mixed batch reactor was used to simulate conditions of high rates
of mass transfer.  In this situation both the fluid and the bacterial
cells are free to move in all directions and relative velocities are
high.  This well-mixed reactor is used frequently as an idealized model
of the activate sludge process.

The second model is a film flow reactor which is characterized by a
stationary slime layer simulating trickling filter conditions.  In this
model, liquid medium flows over the slime layer in a thin film.  Flow
is parallel to the slime layer so that the degree of contact between
liquid and cell mass is limited to the Interface between the slime layer
and the liquid phase.  This makes for relatively low rates of mass trans-
fer, especially if the liquid film is in laminar flow in which case mass
transfer is limited to molecular diffusion.  The film flow reactor thus
provides a simulation of conditions where mass transfer could be the
rate limiting factor..

These reactor models were used to study the removal of soluble and
colloidal substrates.  Glucose was used as a typical soluble carbohy-
drate and starch as the corresponding colloidal carbohydrate; glutamic
acid and glyclne were used as representative soluble amino acids and
peptone as a typical colloidal protein; lauric acid was used  ^s a typi-
cal lipid; it is soluble at very low concentrations but behaves like a
colloid at higher concentrations.  The results obtained with glucose
as the only carbon  source have been published by the author (San. Eng.
Divt> ASCE, SA4 93, 91, 1967), and are briefly summarized as background
Information.

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Glucose Removal in Model Reactors

Process variable studies were carried out using glucose as the only
source of carbon In a liquid medium containing all other growth require-
ments in excess.  Results indicate that glucose removal can be described
analytically in terms of growth kinetics 'of the microorganisms for the
well-mixed reactor and mass transfer of nutrients for the film flow
model.

In the well mixed reactor system, the rate of removal of glucose was
independent of glucose concentration (above ten mg/1) but directly
proportional to the amount of active cell mass.  Ihis is consistent with
the fact that high rates of mass transfer are obtained in a well-mixed
reactor.  Thus rate of glucose removal is determined by the rate of
metabolism of the microorganism.

On the other hand the film flow reactor, in which the bacterial mass
(slimelayer) remains stationary at the retaining wall while medium
flows' over it in a thin film, showed a marked reduction in the rate of
removal as glucose feed concentration was reduced below 100 mg/1.  In
this situation the quantity of bacterial mass as measured by slime
thickness had no effect on the rate of removal.  These results are con-
sistent with the fact that- the film flow reactor is a mass transfer
limited system because mass transport of nutrients from the liquid
film to the slime layer is by molecular diffusion, which is slow.

Colloidal Substrates - Physical Characteristics

Removal of colloidal substrates could be expected to follow a similar
pattern as soluble substrates except where particle size becomes a
factor.  Pertinent physical characteristics of water, glucose, starch,
and bacterial cells are shown below.

          TypicalHjDGlucoseStarchBacterium
	Dimensions	

Molecular weight,                                /-              „
g/mole                   18        180         10°          101

                                                 p            ii
dam.,  angstrom           4         10         10           10

Diffusion
coefficient,             	     0.6 x lO"0   0.08 x 10 ')   —

cm /sec.
  Weight of 6.0 x 1023 cells.

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Molecular diinension have a direct effect on mass transfer rates because
larger molecules diffuse more slowly as shown by the lower diffusion
coefficient for starch vs. glucose.  Mass transfer by molecular diffu-
sion is proportional directly to the diffusion coefficient and the con-
centration gradient.  It follows that mass transfer of starch is approx-
imately eight times less than glucose under the same concentration grad-
ient .

Molecular size also is an important factor when considering permeabil-
ity of cellular membranes.  Glucose molecules are sufficiently small
to pass through the cell wall and semipermeable membrane (cytoplasmic
membrane) which surrounds bacterial cells.  However, the diameter of
starch molecules is some 100 times larger and approaches cellular
dimensions.  As a result it is unlikely that starch molecules can be
absorbed directly.

Metabolism of Colloidal Substrates

The mechansim by which microorganisms metabolize large particles or
colloids centers on two possibilities.  The microorganism either can
evolve a mechanism for engulfing and secreting the appropriate catabo-
lic enzymes within the cell confines, or they can excrete the necessary
enzymes into the surroundings to cause the reaction sequence to proceed
outside of the confines of the permeable membrane of the cell proper.

According to Pollock  (The Bacteria, Vol. 4, Acad. Press, 1962), the
engulfing processes or direct passage of large molecules into cells
(referred to as phagocytosis and pinocytosis) generally are associated
with large cells and/or higher forms of life than the Eubacteriales.
The rigid cell wall of Eubacteriales would make it difficult to dev-
elop a mechanism for passage of large molecules through the cell wall,
whereas higher forms  (e.g., amoeba) are surrounded by an elastic mem-
brane, free to fold and form vacuoles.  Pollocks' review of some 280
references leads him to conclude that bacterial metabolism of large
molecules is mediated by exoenzymes which are available outside of
the semipermeable membrane (other'authors perfer the term extracellular
enzymes).

The mechanisms and controls by which exoenzymes are produced and/or
liberated outside of the semipermeable membrane is not understood.  As
a result, it is not possible to predict the influence of process varia-
bles on the kinetics of colloid degradation. . Control mechanisms for
exoenzyme production have been deduced for a few pure culture systems
using simple substrates.  The adaptive response mechanism is the control
mechanism most widely mentioned.  Fukumoto (Proc. Intl. Symp. Enz. Chem,,
Academic Press, 1958) has shown that the formation of a-amylase in a
medium free of starch substrate is negligible but can be stimulated by
the addition of substrate even in the absence of nitrogen.  The work
by Rogers (Bioch.•Jdurn. 39, 435, 1945) on synthesis of hyaluronldase
into the growth medium gives support to the concept of adaptive response

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In Streptococci but suggest that other influences can become predomin-
ant as evidenced by the need for a peptone factor to stimulate forma-
tion of hyaluronidase.  If adaptive response is the controlling mech-
anism, then concentration of substrate should be an important parameter
in the description of the kinetics of colloid degradation.

Nomura (Bloch. Journ. 43, 84l, 1956) has explained the control mech-
anism in terms of the concept of competitive synthesis.  The cell pro-
tein in synthesized preferentially and, in the absence of adequate
nutrients, synthesis of cell protein stops and amylase formation pre-
ceeds.  If competitive synthesis is the controlling factor, then the
effects of colloid concentration would be secondary and the concentra-
tion of competing substrate solutes would be the most important para-
meter .

The work of Reynolds (Jour. Gen. Microbio., Britl, 11_, 150,- 195*0 on
chitinase activity is interesting particularly because the results show
that agitation of the medium and culture resulted in increased chitinase
activity.  This suggests that mass transfer is a limiting factor in
certain colloidal systems and must be considered.

The present state of knowledge of metabolism of colloids can be sum-
marized by explaining that there-are various hypotheses which describe
specific observations but there is no generally applicable theory.
The available Information does not permit making apriori predictions
about the kinetics of colloid removal in the systems of interest in
waste water treatment.

The first phase of the experimental work therefore was designed to
study the effects of colloid concentration.  Measurements were design-
ed to establish the relative rates of colloid degradation and utiliza-
tion of the degradation products using starch as a representative
colloid.  Subsequent tests were carried out in the presence of other
substrates to establish whether there is a competitive effect.  Five
different starches were evaluated.  Protein and fatty acid degradation
was also studied.

Kinetics - Growth and Enzymes

The underlying process in biological treatment of waste waters is the
metabolic activity of microorganisms which utilize the organic materials
as food for growth.  Oxidizable substrates such as carbohydrates, lipids
and proteins serve+as a source of carbon and energy.  Inorganic sub-
strates such  as NH|. and ELS can also serve as sources of energy for a
few species.

Microbial growth also requires a source of nitrogen, oxygen (aerobes),
sulfur,  phosphorous and a broad range of inorganic salts in low concen-
trations.   It may be assumed that all the required salts are present in
excess  in municipal waste waters.  However, nitrogen and phosphorous may

-------
be deficient in certain industrial wastes.

Given a system where all nutritional requirements are available in
excess, microbial growth will generally proceed rapidly until eventual-
ly one of the required nutrients is depleted.  For this type of growth
situation the rate of growth can be described by:

               (1)  dN _
                    dt
          Where N = cell mass concentration
                y = growth rate coefficient
                t = time

The growth rate coefficient has a unique maximum value for each species;
it is temperature dependent, affected by pH, and substrate concentration.
The effect of substrate concentration has been described by Monod and
can be represented by the equation:
                                 g
               (2)  y = y max v   , „
          Where  S = substrate  concentration
               K = adsorption coefficient
                 C
             y max = maximum growth rate coefficient for the environ-
                    mental  conditions.

The adsorption coefficient  has the units of substrate concentration and
takes the numerical value of the  concentration  where the rate of .growth
is one half  its  maximum value.  Substitution of equation (2) into (1)
leads to the generalized growth rate equation which now has two depend-
ent variables, S and N  both of which are time dependent.

               (3)  dN         	S_ N
                    dt   y  mx K  + S
                                c
One dependent variable  can  be  eliminated by using the relationship be-
tween yield  of cell mass and amount of substrate consumed.

The relationship between cell  mass synthesis and substrate utilization
has been the subject of extensive investigations with pure cultures as
well as with mixed cultures.   In  theory, there is a unique relationship
between synthesis of cell mass and the substrate consumption which is
defined analytically by equation  (4).

               (4)  dN  _  v dS
                    dt  " "Y dt

          Where  Y = yield coefficient, weight of dry cell mass produced
          1!         per unit weight of substrate consumed.

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The yield concept follows from the hypothesis that synthesis is the
net result of a series of biochemical reactions (metabolic pathways)
wlrLch produce protoplasm and release energy from the oxidation of
substrate.  As long as the same metabolic pathways are involved, the
yield of cell mass per unit weight of substrate has a constant value.
In practice, this condition is at best an approximation, which is
acceptable as long as the changes in environmental conditions are not
extreme.  Assuming the yield coefficient to be constant, equation (4)
can be integrated between limits to give:

               (5)  N - No =  -Y(S - SQ)

          Where N  and S  are the initial concentrations of cell mass
ans substrate respective2y.  Using the yield relationships to eliminate
the dependent variable N from equation (3) gives:

               (6)  - dS =   max    S   (SQ - S + NQ)
                      dt         KC + S           -y

A similar equation can be obtained in terms of cell mass, N.  Equation
(6) is readily integrated for K  .and Y constants, and gives:

               (7)  In  S + B   + K   lnJs(S  + B)
                        S  + B     c  —/o f~ ,  p\ ( = y max t
                         o              / ^Q^ T B;
          Where In = natural logarithm

                 B=  -VSo
                       Y

Equation (7) describes substrate concentration as a function of time in
terms of the maximum growth rate coefficient, the yield coefficient and
the adsorption coefficient K  as parameters.  For the special case where
K  is negligibly small,, i.e., at high substrate concentrations, equation
(7) reduces to the form:

               (8)  In  S + B       max
                        S  + B
                         o
Either of the above equations can be used to predict the course of sub-
strate depletion in a well-mixed batch reactor.  As a rule, values of
N  and S  can be obtained by direct measurement.  The yield coefficient,
Y, can be measured directly by harvesting the cell mass and simultaneous
measurement of substrate depletion.

The maximum growth rate coefficient y max may be evaluated from data
obtained at relatively high substrate concentrations using equation
(8); alternatively both K  and y max can be evaluated by trial and
error from two independent sets of observations of substrate depletion
as a function of time.
                             10

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Data on the enzymatic degradation of colloids was analyzed in terms
of a simple model where the rate of hydrolysis is defined by equation
(9):
                    dt

          Where C = concentration of starch
                t = time, min.
               K-, = rate constant

                E = enzyme concentration.

Concentration of enzyme is assumed to be directly proportional to cell
mass concentration, E ^ N.  Substituting into Equation  (9):
          Where k Incorporates a proportionality constant which relates
enzyme concentration and cell mass concentration.

The concentration of cell mass, N, can be replaced by the growth rate
equation which relates cell mass at any time, t, to the initial con-
centration N  and the growth rate coefficient \i max as shown in
equation (11;:

               (11)  N = N  [eymaxt]

Equation (11) applies as long as y max remains constant (logarithmic
growth phase)

               (12)  -dC=kN  ^y^t-j
                       crc     o

Integrating between limits,

               (13)  C -C = kN   r P   t   m
               v      o       o  [e max  - 1J

                            Hnax

Mathematical Analysis of Film Flow Reactor

Prom a theoretical viewpoint, the film flow reactor has three advantages.
(i)  It holds the biologically active mass stationary and thus permits
the making of rapid changes in environmental conditions such as composi-
tion of the growth medium and concentration of substrate,  (ii)  It
allows for instantaneous control of the flow of nutrients,  (iii)  It
allows regulating contact time between the bacterial mass and the med-
ium, independent of flow rates.
                              11

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  The disadvantages stem from the relatively low rates of mass transfer
  which limit removal of nutrients at low concentrations of nutrient.
  It has been shown from considerations of Reynolds number that the flow
  on a flat, incline plane is in the laminar flow regime.  Laminar flow
  can also be demonstrated by the use of dye injections which show that
  the flow lines are parallel to the surface of the slime layer.  It
  follows that mass transport of nutrients from the liquid film to the
  slime layer is by molecular diffusion, which is relatively slow.  How-
  ever, the flat plate reactor has the advantage that the rate of mass
  transfer by molecular diffusion can be described mathematically, so
  that it becomes possible to distinguish between the situation where
  mass transfer is the rate-limiting factor.  A general mathematical
  model which describes mass transfer and reaction at the solid surface of
  the inclined plane has been described by the auther (San. Eng. Div.,
  ASCE, 93, SA4, 91, Aug. 196?) and is briefly summarized below.  The
  mathematical model is obtained from a material balance over an infinite-
  simal control volume as illustrated in Figure 1.
                     -Liquid
Solid      w
Support    / ^
                            FIGURE 1

               SCHEMATIC DIAGRAM OF CONTROL VOLUME

  At  low energy gradients the flow regime is laminar and velocity is
  described by equation (14):

                  (14)  V = pgsing (62 -X2) = G(S2-X2)
                             2y
  in  which  V = velocity, in grams per centimeter,
            p = density, in grams per centimeter,
            g = gravitational constant, in centimeters per second squared,
            y = viscosity, in grams per centimeter-second,
            g = angle in inclination,
            5 = thickness of the liquid film in centimeters, and
            X = distance from surface of film, in centimeters.
                               12

-------
Let CA represent the concentration of the limiting or potentially
limiting substrate (.Component A).

The material balance assumes that there is no production nor use of
component A in the control volume.  In effect, this means that there
is no growth in the liquid film per se and that all metabolic activity
takes place in the slime layer.  However., the possibility of growth and
use of nutrients in the liquid film was checked experimentally and
found to be below detectable limits.  Flux of component A in the Z dir-
ection is approximated by convective transport (equation 14).  Flux in the
 X  direction is limited to molecular diffusion.  The resulting
differential equation for the steady state is:
                         2
               (!5),  -D 9 °A   + G (<52 -X2)  3CA  = 0.
                         3X2                 3Z

Where D. i| the molecular diffusion coefficient of component A in
water,  cm /sec.  Proceeding on the assumption that the surface of
the slime layer is the major site for assimilation and metabolic de-
gradation of component A, the solution of equation (15) is subject to
three boundary conditions:

               (16)  Dfl 9CA  = 0 at X = 0
                      H 3X


                        3CA
               (17) -DA T~  -R" = 0  at X = 6
                (18)  CA  =  CAQ         at Z = 0 for 0 < X <  6

The first boundary condition states that there is no mass transfer
across the interface between the  liquid film and air at X = 0.  The
second boundary condition  states  that the rate of transfer of component
A across the interface between the liquid and slime layers at X = 6, is
equal to the rate of removal of component A by assimilation at the slime
surface.  The  term R" is a function of the metabolic activity of the
microorganisms  in the surface of the slime layer.  Boundary condition
No. 3 states that the concentration of A in the liquid film at the inlet
to the plane (at Z = 0)  is uniform and is represented as CAQ

Boundary condition No. 2 was approximated by assuming that for active
biological slime layers  R" >»DA  (3CA/3X) which leads to the approxima-
tion that the  concentration of component A at the interface is zero.
The corresponding boundary condition-No. 2 becomes

                (19) CA ~  0 at X = 6.
                              13

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Integration of equation (15) and transforming the variables into
dimensionless form gives the following equation for c, the vertical
average concentration from the film flow reactor, at any point Z down-
stream from the inlet.

                                    2       I
               (20) c* = 3/2 I e  ~AnZ* An '   (1-xJ) ^(X%,An)dX*

                            An              0

in which c% = dimensionless average concentration of nutrient at any
point Zx on the plane,

          X = eigenvalue obtained as a result of boundary condition
              no. 2,                                                  „
          A = coefficient which is a function of A and Xx,
         ¥„ = power series in X^

and Xx = dimensionless distance from the surface of the liquid film,
and Zjj = dimensionless distance from the inlet.  (The variables have
been expresses in dimensionless form to simplify the solution).

Equation (2) has been evaluated and the solutions compared with experi-
mental results.  Solutions for equation (2} are graphed in Figure 2,
which relates the average concentration c (dimensionless) to the dimen-
sionless variable Z  defined as follows:
               —    C                         X
               c* = _A                  ^* =  ~$
                    C AO
          Where C.  = average concentration any point Z, mg/1

               C.Q  = inlet concentration, mg/1

                 Z  = distance from inlet, cm.

                DA  = molecular diffusion coefficient, cm /sec

                 G  = p g sin 3/2y as defined by equation (14)
                 5 = thickness of the liquid,  film, cm.

-------
                                FIGURE  2
                                 SOLUTION  EQUATION  20
C.CCCI
                            ( DJrtAENStONLESS  VARIABLE)

-------
 Waste Water Composition                                       £

 A thorough, understanding of the composition of waste waters is essent-
 ial in evaluating the effectiveness of various types of treatment and
 pollution effects on the environment.   Several investigators have ana-
 lyzed composites of municipal sewage with a view to identifying and
 measuring the organic constituents.

 Composite samples were obtained from municipal sewage systems and
 subjected to physical separation methods  to recover solids.  The solid
 fractions were then analyzed for the major classes  of organic materials.

 Large particulate matter was removed by sedimentation for 1 hour.  The
 supernatant from sedimentation was  then subjected to centrifugation to
 remove a second fraction of solids. The  centrifuged liquid was then
 passed through a candle filter to remove  large colloids.   (Candle filters
 have been used for removing bacteria from suspension.  However, it is
 most likely that colloids such as proteins and polysacherides can pass
 through the candle filter).  The final fraction of  solids was determined
 by evaporation and includes both solutes  and small  colloids.  Results
 are shown below.
      *
           Treatment                Amount of Solids Removed as mg/1
                                    of  Carbon	

           1.  Settled 1 hour                 110
           2.  Centrifuged'                    130
           3.  Candle filtered                 54
           4.  Filtrate                       118
               (evaporated)

*Water polution Research, Report of  the Water Pollution Research Board
 Laboratory, Stevenage, England 1959-61.

 A chemical analysis of the solids from fractions 1, 2, and 3 is shown
 under the heading "suspended Matter".   Composition  of the solids from
 the candle filtrate is shown as "filtrate".
                                        Concentration as mg/1 of carbon
 Constituent              Total      Suspended Solids  Candle Filtrate

 Carbohydrate             77-1          21.1                56.0
 Amides                    2.4            2.4
 Amino Acids - Free        6 = 3          	                6.3
             -Bound      70.7          63.3                 7-4
 Acids     - soluble      17.3            6.7                10.6
         - insoluble      71.6          71.6                	
 Esters                   46.9          46.9                	
 Anionic  Surfactants       9.3            2.0                 7.3
 Great inine                3.0                                3.0
                              16

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Total Organic carbon

     - by analysis       412         294               118
     - by addition       304.6       214                90.6

Inspection of the results shows that the carbohydrates are primarily
solutes and small colloids.  However, the bound amino acid group is
primarily large colloidal or particulate matter which can be removed
physically.  The most noticeable group of constituents are the lipid
related compounds (acids and esters) which account for more that 45$
of the total organic carbon.  The major portion of the lipid material
is in the large colloidal and particulate fraction with only small
quantities showning up in the candle filtrate.

The results obtained by Hunter  (J. Water Poll. Cont. fled., 37, 1142
Aug. 1965) show similar trends.  Composite samples of sewage were sub-
jected to successive physical separation steps, sedimentation, centri-
fugation and membrane filtration which are referred to as settleable,
colloidal and supra-colloidal particulates respectively.  Total part-
iculate solids are approximately 80 percent organic matter, while the
soluble-fraction solids are approximately 30 percent organic matter.
.Approximately 64 percent of the total wastewater solids is contributed
by the soluble fraction, but only 40 percent of the total organic mat-
ter is contributed by this fraction.

The particulate fractions were composed largely of grease (17 percent),
amino acids (19 percent), and carbohydrates (24 precent).  The grease
was found to be principally esterified fatty acids and unsaponifiable
matter.  Free fatty acids were present only in small amounts.  The
amino acid nitrogen content of the particulate fractions averaged only
about 50 percent of the particulate organic nitrogen.

The organic compositions of the three particulate fractions were some-
what similar.  The main difference was found in the considerably high-
er amino acid and hemicellulose contents of the supracolloidal fraction
and the considerably higher cellulose content of the settleable solids.

The "soluble organic matter was found to be composed largely of ethyl-
ether-extractable matter, of which the organic acids were the primary
constituent (56 percent).  The other organic constituents present in
significant quantities were the amino acids and sugars.  ABS, volatile
acids, phenols, cholesterol, uric acid, and creatine-creatlnine were
found to be minor constituents.

On the basis of these analyses, it is clear that typical sewage is
a composite of a wide range of organics.  All the major classes of bio-
chemical conpounds are represented, carbohydrates, amino acids - pro-
teins and lipids.  For the purpose of this study substrates were chosen
to give one or more soluble and colloidal compounds from each of the
major classes of biochemical compounds.
                             17

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                              Soluble        .Colloidal
                                                 s?f
Carbohydrates                 glucose        starch
Amino Acid-protein            glycine,       peptone
                              glutamate
Lipids                        laurate        palmitate, stearate

Preparation and analytical procedures are discussed in the following
section.
APPARATUS AND EXPERIMENTAL PROCEDURE.
BATCH REACTOR

Two model reactor systems were used to study the rate of biological
growth and the kinetics of removal of substrate.  Batch reactors were
used to simulate conditions of high rates of mass transfer. " The vessels
were agitated by introducing air through sparging devices.  Sparging
provides for both rapid mixing and an excess supply of oxygen for the
biological system.  The sparging air was pre-saturated with water by
passing it through a wet packed column.  Batch reactors in a size range
of 250 milliliters to 2 liters were used depending on the length of the
experiment and the number of samples to be obtained.  Batch reactors
were used to study the effects of process variables such as temperature,
concentration of substrate, type of substrate, and concentration of
microbial cell mass.  In any given series, all reactors were started
at about the same time using aliquots of the same feed materials and
innoculum.  Samples were withdrawn at predetermined time intervals and
immediately filtered through a 0.^5 micron multipore filter to remove
active cell material.  Samples were then stored under refrigeration
for anaylsis at a subsequent time.
FILM FLOW REACTOR

This reactor is characterized by a stationary slime layer.  Peed sol-
ution is allowed to flow over the slime layer in a thin film.  Plow is
parallel to the slime layer so that the degree of contact between li-
quid and biological film is limited to the interface between the slime
layer and the liquid phase.  At the conditions used in this experiment,
namely relatively low flow rates, and very low hydraulic gradients, the
liquid film is considered to be in the laminar flow regime.  It has
been shown by the.author (Journ. San Eng. Div., ASCE, 93, 91, 196?)
that under such conditions mass transfer is very slow because it is
limited to molecular diffusion from the liquid film to the interface
of the slime layer.  The film flow reactor thus provides a simulation
                              18

-------
of conditions where mass transfer is, or could be, the rate limiting
factor in the consumption and removal of substrate and the growth of
the microbial cells.

The film flow reactor consists of a machined flat surface made of clear
plastic with the dimensions shown in Figure 3.  The plastic is bolted
to a metal frame to prevent warping.  Peed solution is introduced into
a distribution or stilling basin whence it passes over a precisely mach-
ined overflow weir.  Channelling and short circuit ing through the still-
ing basin was observed initially, but was overcome by the use of a dis-
tribution grid.  The grid consisted of wire mesh designed to provide
pressure drop and thereby randomize the flow pattern through the still-
ing section.  The outlet section was separated into three parts.  For
most analyses, samples were taken only from the center section which
collected about 2/3 of the flow.  The end sections were generally dis-
carded because of wall effects, associated with the more rapid flow In
the vicinity of the side walls.  The slope of the plane was adjusted
with a nut and bolt attachment at the upper end.  The lower end was
supported by a two point swivel support.  This method of attachment
facilitates leveling from side to side and allows changing the slope
very easily.                                               :

The surface of the plate was  covered with a fiberglass fly screen which
serves as a structural framework for building up the slime layer.
Growth of the slime was initiated by seeding the feed solution with
effluent from a continuous propagator.  After a few hours of seeding,
the plane was allowed to stagnate and allow the biomass to settle into
the screen.  Thereafter, feed solution was continually passed over the
plane and in general, growth was established within a matter of a few
days.  Measurements of the screen volume showed that the void spaces
account for about 80$ of the volume defined by the edgeview volume of
the screen.  After the biological materials had filled the voids,
excess growth was periodically removed by scraping the surface with
a knife edge.  The thickness of the slime layer was thus controlled
to the approximate thickness of the screen, approximately 0.05 cm.
thick.  Thicker slime layers were obtained by superimposing several
layers of screens; 0.08 cm. for 2 screens, 0.11 cm. for 3 screens and
0.14 cm. for 4 screens.
                              19

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                            F1GUHK  3
Fiberglass
screen
Overflow  weir.
                                        Feed
                                           Inlet
                      FILM FLOW REACTOR
                                   20

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CONTINUOUS PROPAGATOR

A small continuous flow, constant volume, agitated reactor was used as
a source of actively growing and acclimatized microorganisms (Chemostat
type system).  A sparger was used to introduce air to insure high oxy-
gen concentrations and to provide good mixing.  Peed was introduced by
gravity flow through a capillary tube to control flow rate.  Excess was
allowed to overflow to waste or collected as needed.  In this type of
system, liquid feed rate determines residence time and to some extent
the amount of growth.  It also controls the rate at which microorganisms
are flushed out of the propagator and hence offers a simple method of
regulating the concentration of microorganisms.  The continuous pro-
pagator was originally seeded with a small sample of sewage obtained
from the Minneapolis-St. Paul Sewage Treatment Plant and contained a
large variety of microorganisms.  The propagator was operated for sever-
al weeks, using the feed solution to be tested, in order to acclimate
the microorganism population.  Periodic inspection showed that a mor-
phologically similar culture was produced within a matter of days.
This is not to say that this was a pure culture, however, for all prac-
tical purposes the predominance of the acclimitised .species made it be-
have as though it were a pure culture.  The continuous propagator efflu-
ent was used as innoculum for all batch tests as well as for seeding
the film flow reactor.  A separate propagator was used for each new
feed stock or feed solution that was tested.
WED SOLUTIONS

Feed solutions were prepared using distilled water in a buffering salt
solution.  The composition of the salt solution is listed below:

     Chemical Formula                Milligrams/liter

     KH2P04                                  42

                                             106

                                             164
     NH^Cl                                   259

                                             106
      CaCl2                                   12

            —6H20                            1
                              21

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Reagent grade chemicals were used throughout.  Soluble organic substrat-
es  consisted of glucose, glutamic acid, .dycine, and lauric acid.  Col-
loidal substrates  consisted of various, starches, and proteins.  Fatty
acids, such as lauric, palmitic, and stearic, probably behave as col-
loids because of their low solubility  . ' There was some evidence of
removal of fatty acids during millipore filtration, suggesting that some
of  the fatty acids tend to agglomerate and form miscelles which are of
 colloidal dimensions.
 ANALYTICAL  PROCEDURES

 Glucose was measured using a commercially available enzyme system sold
 under the name of Glucostat (Worthington Chemical Co., Freehold, N.J.).
 This  method of analysis has been used successfully by a number of in-
 vestigators.  Glucostat reagent contains glucose oxydase, which oxydizes
 glucose to  gluconic acid with the release of hydrogen peroxide.  The
 hydrogen peroxide is in turn oxidized by a chromogen in the presence of
 the enzyme  peroxidase.  The oxydized chromogen has a distinctive yellow
 straw color which has a strong absorption band in the 400-500 millimicron
 range.  Color intensity was measured in a Coleman Spectrophotometer and
 glucose contents calculated by reference to known standards which were
 tested with each batch of 10-15 samples.  Samples containing high con-
 centrations of cell materials were filtered before measuring transmit-
 tance to eliminate absorption by cell material.

 Carbon concentration was measured in a Beckman Total Carbon Analyzer,
 as described by Van Hall (Anal. Chem. 35, 315, 1963).  Samples were
 filtered through a 0.45 micron millipore filter to remove cell material
 prior to carbon analysis.  The carbon analyzer consists of a. combustion
 tube  followed by an infrared cell to measure the concentration of carbon
 dioxide produced in the combustion system.  The combustion train operates
 at 940°C in the presence of a cobalt molybdate catalyst, and air at at-
 mospheric pressure.  The combustion gases pass through a condenser to
 remove water, and are then analysed for carbon dioxide in a balanced
 infrared cell which gives a direct readout in terms of milligrams of
 carbon.  Samples containing more than 100nig/l of carbon were tested by
 injecting smaller aliquots (ten microliters), or the samples were diluted
 to the range of 1 to 100 milligrams per liter of carbon.  The readout
 system covers a range from 0 to 100 milligrams per liter of carbon.
                                                                 -f
                                                                 ;
 Amino acid  concentration vras measured using ninhydrin reagent.  The pro-
 cedure was patterned after that described by Yemm and Cocking (Analyst,
Volume 80, March 1965, pp. 209-213).  The method gives stoichiometric
reactions with ninhydrin reagent for most amino acids and is both easy
to use and reproducible.  Ammonia does react and" has to be corrected for,
or eliminated from the sample prior to testing.  The test procedure was
 calibrated using both glutamic acid and glycine.  Ammonia corrections
were made using direct Nesslerization to establish ammonia concentration,
                             22

-------
and then using a calibration chart of absorbance versus ammonia concen-
tration, to incorporate corrections for specific samples.  The hydrol-
ysis products of proteins react like amino acids and give a positive
reaction.

Cell mass was measured by filtering and weighing the dried solids
through a 0.45 micron millipore filter.  The technique is patterned
after that used by Engelbrecht and McKinney  (Sewage and Industrial
Wastes, 28, 11, 1321, November 1956).  This test provides a direct
measure of the biomass and suspended solids but does not differentiate
between viable cell mass and debris.  The millipore filters were pre-
washed and predried prior to use and again weighed after drying at
103°C.

Proteins were measured using Polin-Phenol reagent.  The method is pat-
terned after that described by Lowry et al.  (Journal of Biological Chem.
193., 265, 1951).  The Polin reaction involves the peptide bonds of ty-
ros ine and tryptophane in the protein.  The final color is the result
of two reactions,  the reaction of copper with the protein in an alka-
line solution, and the reduction of the phosphomolybdic—phosphotungs-
tic reagent contained in the Polin-phenol reagent.  The Polin reaction
requires only 1 milliliter of sample.  There are no apparent interfer-
ing substances and the determination is quite sensitive and easy to
perform.

Starch contents were determined in a modified iodine test.  The iodine
test is described in section B of this report (Iodine Reaction and
Carbon Determination of Starches).
BATCH REACTOR TEST RESULTS

Chemistry of Starch

Starch is a naturally occurring polysaccharide material consisting of
glucose units jointed by a, 1, 4 linkages and to a lesser degree by a,
1, 6 linkages.  Starches fall into two classes, amylase, which is be-
leived to be a long unbranched chain, and amylopectin which has been
shown to be a branched  chain  structure with one terminal glucose unit
for every 20 to 30 glucose residues.

Hydrolytic cleavage of starches is mediated by a variety of enzymes;
amylolitic enzymes are the most common; phosphorylases and amylcglucon-
sidases occur in special situations.  The amylases fall into two cate-
gories; a amylases (a, 1, 4 glucan 4 glucanohydrolase) catalyse the
scission of a, 1, 4 glucosidic bonds at random resulting in- a rapid re-
duction in molecular weight, viscosity, and light scattering; B amylas-
es (a, 1, 4 glucose maltose) catalyse the scission of maltose units from
the non-reducing end of the chain; producing high yields of maltose but •
                             23

-------
 a more  gradual reduction In the physical characteristics of the starch
 substrate.  B amylase activity ceases when a branch point  (a, 1, 6 bond)
 is  reached.  The resulting polysaccharide fragments that remain after
 B amylase hydrolysis are called dextrins or limit dextrins.
           Enzymes that catalyse cleavage of the a, 1, 6 bond have been
 found in both intestinal bacteria and associated with certain other
 bacteria.  However, relatively little information is available.

 Characterization of Starches

 Six different starches were tested.  Soluble potato -starch (Reagent
 grade)  was used as a reference.  The other starches were obtained from
 A.E.  Staley IManufacturing Company (P.O. Box 151, Decatur, Illinois
 62525).

      PPPS = Unmodified corn starch
      ES-A = Eclipse A. lightly acid converted corn starch
      ES-G = Eclipse G, highly acid converted corn starch
      SD-5 = Stadex #5j lightly dextrinized corn starch
     SD-80 = Stadex #80, highly dextrinized com starch

 Iodine  Reaction and Carbon Determination

 The starch iodine test is a widely used and simple test.  However, as
 a quantitative test it is subject to a number of variables, specifical-
 ly  the  molecular weight and bonding structure of different starches.
 Iodine  reacts with amylase to yield a deep blue color complex with  „,
 approximately one iodine molecule per 7-8 glucose units. (Physical  •
 Characteristics of Polysaccharide, Florkin and Stotz, p. 189).Iodine
 is  believed to be complexed in the core of the helically arranged glue-
 cose  chain.  At least 30-35 glucose units are needed for full color
 development.  Shorter chains give a red color with maximum absorption
 peaks in the 520 millimicron region.  Chains of less than six glucose
 units give no color reaction.

 Iodine  reagent used for starch determination was made up periodically
 using 0.2 wt. % iodine in 2.0 wt. % solution of potassium iodide.
 Equal volumes of iodine reagent and sample were mixed and allowed to
 stand for 15 minutes.  The color was measured in a Coleman Stectrophoto-
 meter at 520 and 680 millimicrons.  Absorbance at 680 millimicrons is
 related to the concentration of amylase units with a long chain length
 of  the  order of 35 and higher.  Absorbance at 520 millimicrons is relat-
 ed  to the concentration of the shorter chain lengths, of the order of
 8-12.

 Carbon  contents of starch solutions were measured in the Beckman Carbon
Analyzer.  All starches gave essentially equivalent results, and approach
 the theoretical value of 44.5 wt %, carbon.  However, there are substant-
ial differences between starches in the iodine reaction as indicated
below.

-------
 Starch                   Concentration for 10$    Transmittance, mg/1

                               520 my                  680 m y

 Soluble starch                96.5                     123
 PFPS                          160                      148
 ES-A                          109                      112
 ES-G                          102                      114
 SD-5                          116                      143
 SD-80                         93*                      84**

 * 50%
**
 Molecular Weights of Starches

 Molecular weights were estimated from right angle light scattering
 measurements of concentrated solutions as described by Debye (Journ.
 Physical and Colloidal Chemistry'51, 18, 19^7).  Molecular weights are
 in the range 30 x 10  for the soluble starch to 220 x 10  for the ES-A
 sample after 5 minute autoclaving in distilled water.  These values are
 substantially higher than the molecular weight determinations reported
 in the literature using chemical methods.  Stacy and Poster (Journ.
 Polymer Science, 20, 57, 1956) have pointed out that physical methods
 of molecular weight measurement generally give higher values than the
 chemical methods; literature values-based on chemical determinations
 are in the range of 160,000 to 360,000 grams per mole for corn amylo/-
 pectin whereas light scattering gave values in the range 40-100 x 10
 grams per mole.  One likely explanation for these differences is that
 starch is a mixture of different molecular weight fractions depending
 on the source as well as prior treatment.  Thus it appears likely that
 processed starches would have a different mixture of high and low mole-
 cular weight constituents.  The work of Stacy and Poster provides sup-
 port for this explanation; they report a molecular weight of approxi-
 mately 30 x 10  for limit dextrins preparedgby B amylase degradation
 of corn amylo pectin as compared to 80 x 10  for the untreated amylo
 pectin.  (It is assumed that B amylase does not catalyse internal
 hydrolytic scissions).

 Jeanes. (Encyclopedia of_ Polymer Science and Technologyg Vol. 4., )
 reports weight average molecular weights of 40-50 x 10  for dextrans
 produced in growing cultures of L. Mesehterloides.  One dextran pre-
 paration showed a molecular weight of 97 x 10  (weight avarage) usgng
 light scattering and a number average molecular weight of 1.7 x 10  and
 365,000 as determined by chlorous acid and copper reagent respectively.

 Sephadex Gel'Separation of Starches

 Sephadex gel columns were used to evaluate the molecular size distribu-
 tion of various starches.  The objective was to determine the quantity
                              25

-------
 of low molecular weight  polysaccharides  associated with each type of
 starch.

 Three sizes of gel material were obtained from Pharmiacia Pine
 Chemicals Inc. (800 Centennial Avenue, Piscataway,  N.J.).
                                                  i
      Sephadex Type                   Molecular Weight
                                      Fractionation Range (Dextrans)
                                                /

      C-15                               0-1500 '
      G-75                            1000-50,000
      G-150                           1000-150,000

 The gels and the columns were prepared in accordance with the descrip-,
 tive literature provided by the manufacturer.   Columns  2.5 cm in dia-
 meter and gel beds of 60 cm.  were used.   The starch was layered into
 the column surface and eluted with distilled water.  Eluent was tested
 for carbon (carbon analyzer) and starch  using  the  iodine test.   The
; results from the starch  determination appear to be  more sensitive.
 Typical eluent curves are shown in Figures 4 and 5.  Blue  dextran 2000
 which has an approximate weight average  molecular weight of 2 x 10  and
 is believed to have essentially no small polysaccharide fragments was
 used as a reference curve.   The quantity of small diameter materials
 was calculated from the  extension of the eluent curve for each starch.

 Gel Column	0-15	G-75	G-150	
                     Percent of Starch Retarded by   Gel %

 Soluble Starch      0                0             0-19
 PEPS                4              /  0-14         9
 ES-A                0                58
 ES-G                5                6             14
 SD-5                2                18           32
 SD-80               3                60           61

 The results show that with the exception of SD-80  and SD-5 the starches
 have relatively small amounts of polysaccharide below 150,000 molecular
 weight, in the range of  0 - 14%.  There  is almost  no material in the
 0-1500 molecular weight  range.   The Stadex starches show substantial
 quantities of the lower  molecular weight fragments; SD-5 has 32$ below
 150,000,  molecular weight and 18% below  50,000 while the more dextriniz-
 ed SD-80 sample has some 60% in the 1000 to 50,000  molecular weight
 range.   Those observations are in line with the poor iodine color re-
 sponse of SD-5 and especially of the  SD-80 sample.  The SD series of
 starches  appear to have  been treated (dextrinized)  to such a degree
 that molecular size does not allow for formation of the iodine complex.
                              26

-------
ro
                                     FIGURE  4
                         SEPHADEX  GEL  SEPARATION OF SOLUBLE- STARCH
             10
                                                                              100

-------
                                                      FIGURE    5


                                                   GEL  SEPARATION  Of  STAfcCM  SO-5
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-------
Hydrolytic Degradation of Starch

Enzymatic  hydrolysis of starch was measured in batch reactors  using
acclimated innoculum from a continuous propagator.  Reactors  were
sparged with air to provide excess oxygen and to keep the system well
mixed.   The tests were designed to measure initial rates of hydrolysis
at various substrate concentrations and to see how the rates  of hydroly-
sis change with tame.

Innoculum was collected overnight from a continuous propagator   (des-
cribed in section on Experimental Procedure).  Soluble starch concen-
itrate was prepared by autoclaving for 5 minutes.  Small amounts of
1 starch concentrate were added to aliquots of innoculum and starch con-
centrations were measured every 10 minutes using a modified iodine
test as described earlier.  After approximately one hour, another por-
tion of starch concentrate was added and the starch concentration was
again monitored.

Typical results are summarized in Figure 6 (complete data are listed
in the appendix).  Starch concentration drops off rapidly at  the start
of each test but slows down appreciably as the reaction proceeds.  The
rate of starch removal is highest in the test  reactors with  the high-
est initial concentration of starch.  Rates of removal after  the second
addition of starch concentrate are not quite as high as the Initial
rates.  Changes in rates are shown more explicitly in Figure  J.   Rates
of starch removal were calculated for each ten minute time increment,
and compared to illustrate the effect of starch concentration and the
effect of time.  Figure 7 shows that the initial rate of removal is
Independent of starch concentrations above 100mg/l but drops  off at
lower concentrations.

The initial rate data appears to follow. ?Hchaelis-Menton enzyme kinetics
which predict zero order reaction (in substrate) at high concentrations
of substrate and first order reaction in substrate at low concentration.
The calculated adsorption coefficient (Km) has a value of 35mg/l and
the calculated (extrapolated) maximum rate of reaction (Vm) has  a value
of 66 mg/1 per minute for the given enzyme concentration.  Tne  exact
concentration of active enzyme is not known, however, suspended solids
concentration and hence the biomass was measured by millipore filtration,
(40.2,  38.9, 38.2, 37.7 mg/1 for reactors A,B,C,D respectively).   The
calculated rate coefficient is therefore approximately 1.7 per minute
(mg/1 starch per mg/1 biomass per minute).

The open points in Figure 7 represent measured rates of removal at sub-
sequent time intervals.  It is interesting to note the gradual  decrease
in rate of degradation with time, despite the continuing growth of new
biomass which accumulates in the reactor, and is equivalent to  an in-
crease  of 30 to 50% In biomass from the beginning to the end  of the  test.
Furthermore, there was a noticeable increase In rate after the  second
addition of fresh starch substrate.  One possible explanation for these
                              29

-------
                         FIGURE   6
                         DEGRADATION - EFFECT OP STA&CM
18
-68
                 *•
                                       .to
                           30

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                                                     CONCENTRATION
                                                        wg/l

-------
 observations  is  that hydrolyzed polysaccharide fragments  act  as  competi-
 tive inhibitors  of the hydrolytic enzyme; there should be a correspond-
 ing increase  in  the adsorption coefficient,  (Kin).  The dashed lines  in
 Figure 7 are  calculated using progressively higher values of  (Km)  at
 otherwise constant conditions.  Increasing (Km) by a factor of four
 accounts for  most  of the  observed drop in rates.

 Comparison of Biological Degradation of Different Starches

 Rates of biological decomposition for each of the 5 starches  were  det-
 ermined in batch tests.  Innoculum was taken from a continuous propaga-
 tor operating on soluble starch solution (lOOmg/1 starch  in salt sol-
 ution).  Starch concentrates (200mg/l) were prepared by autoclaving for
 5 minutes to  dissolve the starch in distilled water.  (Details of  pro-
 cedure and data  are listed in the Appendix under Exp. #4-30-68 and 5-  "
 7-68).  Starch concentrate was added at the beginning of  each test;  air
 was sparged into each batch reactor to provide oxygen and to  keep  the
 system well mixed.

 Starch concentrations are shown in Figures 8 and 9.  More than 50% of
 the starch is degraded in the first 30 minutes; thereafter the rate  of
 degradation slows  dovn.  The initial rates of degradation (first 30
 minutes)  are  summarized and compared below.

              Initial Rates of Starch Degradation

 Starch        Exp. #    mg/1 (first 30 minutes)       Relative Rate

 Soluble
 starch        4-30-68             119                      I'.O

 ES-A          4-30-68             100                        .84

 SD-5  ,       4-30-68             103                        .87
 SD-80          4-30-68              78                        .66
 Soluble
 starch        5-7-68              134                      1.0

 PFPS          5-7-68              151                      1.13

ES-6          5-7-68              115                        .86

Unmodified  corn starch (PFPS) shows the highest rate whereas  the dex-
trinized starches show the lowest rates.  The most highly dextrlnized
starch (SD-80) shows a tendency to level off after 2/3 of the  starch
has been degraded,  thus leaving a substantial fraction, about  1/3  that
is apparently not degradable by the existing enzymes in the first  few
hours of the test.

A smaller number of mlllipore filtered samples were also  tested for
carbon content to determine the rate of removal of carbohydrates.
                             32

-------
6IOLOG»CAL DEGRADATION OF  STARCHES
                   **
        STANCH
10
     $t>   40   -»0  «0
    TIME, MINUTES
                                toe
           33

-------
                     230
FIGURE
   2 00
   !&0
   I&O
   120
£

2
U
0

§ loo
V
                                    fe4»         80

                                TIME,  MINUTES
                     «00

-------
Disappearance of carbon was taken to represent biological- growth because
millipore filtration removes bacterial solids but  does not remove the
starch polysaccharide products of hydrolysis.  Figure 10  summarizes the
data and shows that carbon removal pattern is essentially similar for
all starches.  Ihe sigmoidal curve is typical for  this type of batch
test.  The rate of carbon removal increases  for  the  first few hours
while the biomass undergoes exponential growth;  as growth proceeds,
substrate becomes limiting thereby reducing  growth rate;  the rate of
carbon removal also slows down and approaches zero (constant concentra-
tion) .  The  residual carbon concentration of 10-20 mg/1 is quite typical
for batch tests and probably represents non-biodegradable carbon for
biomass that is available.  The  implications of  this residual carbon
are discussed elsewhere in this  report.   Close inspection of the data
on carbon removal shows that the rate of  carbon  removal for starch SD-80
is somewhat  slower than that for the other starches. The effect is most
likely associated with the slower rate of hydrolysis of the SD-80 starch
which in turn slows down bacterial incorporation of  hydrolyzed carbohy-
drates.  The precise magnitude of the difference in  rate  of carbon re-
moval has not been established but could  be  as much  as 50% in the course
of the test.
                              35

-------
        FIGURE:  10
.BIOLOGICAL
             ! ; ; n , . . . : ; .T.
              :-h::!   . I
I N C OR POR AT IO N _Q,F__
             REMOVAL OF
           6      f
          TIME, HOURS

          .36

-------
Soluble Exoenzyme Activity

Ihe location and control mechanisms of the hydrolytic enzymes that cat-
alyze starch degradation are not well defined.  There is considerable
support for the concept that in bacterial systems exo-enzymes are close-
ly associated with cell walls.  Some enzymes are also released to the
medium in the form of small colloids which pass through 0.45 micron
filters and will be referred to as "soluble" enzymes.  The following
experiments were designed to test for the presence of soluble enzymes
in bacterial decomposition of starches.

Innoculum was obtained from a continuous propagator using soluble starch
feed solution (lOOmg/1).  Fresh feed solution was added at the beginning
of each test; one reactor received the innoculum as collected, the other
reactor received millipore filtered innoculum  (0.45 micron).  Starch and
carbon concentrations were measured for a period of several hours; re-
sults are summarized in Figure 11 detailed data are listed in the Append-
ix as Experiments #2-9-68 and 2-10-68.  There is evidence of exoenzyme
activity, however, the observed rate is only 3% of innoculum.  Similar
results have been reported by other investigators.  Banerji (University
of Illinois, Sanitary Engineering Report, No. 29) has demonstrated the
presence of hydrolytic enzymes in activated sludge liquors.  Millipore
filtration  of mixed liquor, (0.45 micron filter) showed substantial am-
ylase activity;  cell free filtrates from acclimated sludges in the en-
dogenous phase  showed higher  activity than filtrates from sludges in or
near the log phase of growth, 150mg/l/hr versus 20mg/l/hr respectively.
Thus, it appears that prior history and age of the biomass is an impor-
tant variable controlling production and release of exoenzymes.

This idea was confirmed in a  test of effluent  collected form the inclined
plane test  reactor.  Filtered effluent showed about 18$ of the hydrolytic
activity observed on unfiltered effluent.  The slime layer consists of
considerably older biomass and some of which is undergoing endogenous
metabolism and  releasing "soluble" enzymes to the feed solution passing
over the slime  layer.
                              37

-------
      FIGURE   II
 MILM PORE FILTERED
40       60       90
     TIME , MINUTES
         •38

-------
Degradation of Starch-Glucose Mixtures.

A series of batch, tests were carried out to measure the effect of add-
ing glucose and starch substrate to an innoculum that was previously
acclimated to starch as the only source of carbon.  Concentrated sol-
utions of glucose and starch were added at the start of each test;

Reactor                       Nominal Initial Concentrations, mg/1
                              Glucose               Starch

A                               0                     100
B                             100                     100

C                             100                     200
D                             ICO                       0

See appendix Table Experiment No. 8-29-68 and 9-4-68 for detailed
description.  Samples were removed periodically and tested for glucose,
carbon, and starch concentration.

Introduction of glucose with the feed solution has no measurable effect
on the hydrolytic degradation of starch as illustrated in Figure 12.
The decay curve for starch is typical and shows a high initial rate
which then levels off at  lower  starch concentrations.  Comparisons of
the rates of glucose degradation are shown in Figure 13-  The presence
of starch appears to slow down  the initial rate of glucose utilization.
However, the effect is small at equal concentrations (lOOmg/1 each)
and some 20$ greater when 200mg/l of starch was added along with lOOmg/
1 of  glucose.  Tne rate of disappearance of carbon is essentially the
same  in all tests, indicating that growth of biomass is not affected
by the relative concentration of glucose and starch when the innoculum
is acclimated to starch feed.   However, the accumulation of biomass is
greater at the end of the tests which received the largest amount of
degradable carbon.
                              39

-------
                            FIGURE   12

-------
                FIGURE   13
L.D.E 6 RAO ATI O N  OF
ISO     140
   TIME , MINUTES
                                          420
4*0

-------
 Amino Acid Metabolism
 Mlcrobial utilization of amino  acids has received considerable attention
 in the Microbiology,  Biochemistry  and  Sanitary Engineering Literature.
 Rates and mechanisms  of catabolism, and rates  of direct  incorporation
 into protein have been described.  .Amino acid  transport  has been studied
 for a number of microorganisms.  Kay and Gronlund (Journ.  Bact., 97,
 p. 273; 1968) have presented an interesting  comparison of  the  rate of
 transport for Pseudomonas aeruginosa.   The results show  large  differen-
 ces between amino acids,  40  fold differences from a  low  of 1.92 x 1^
 micro-moles per minute per milligram by weight of cells  to 80  x 10 y
 moles/min.  - mg.  (dry weight)  as  shown below.
 Amino Acid                   Rate of  Transport*
 Hydroxyprollne                    0
 Cysteine                          1.92 x 10
 Threonine                         3-54 x 10
 Aspartate                         4.11 x 10
 Serine                            4.20 x 10
 Glutamic                          4.67 x 10
 Proline                           5.75 x 10~4
 Glycine                           5.90 x IQ~^
 T^rosine]                         1.40 x 10~3
 Methionine                         1.99 x 10~3
 Valine                            2.36 x 10~3
 Histidine                     ^   2.74 x 10~3
 Alanine                           2.76 x 10~3
 Phenylalanine                     3.23 x 10~3
 Lysine                            3.36 x 10" 3
 Isoleucine                         3.92 x 10~3
 Tryptophane                        5.20 x 10~3
 Arginine                           6.75 x 10~3
 Leucine                            8.00 x 10~3
*Micromoles/minute  - mg. of dry weight of cells using an  external con-
 centration of 10~" moles/liter.
 These values are particularly interesting because  they also provide some
 insight on the relative rates of removal of  amino  acid from the  surround-
 ing medium; removal rates are in the range of  .02  to 0.1 wt. % on cell
                             42

-------
mass per minute; thus indicating that these ceils are highly effective
for the removal of amlno acids from dilute solutions.  It has also been
shown that incorporation of amino acids is energy dependent, and  is
probably mediated by transferases, therefore energy metabolism is a
prerequisite for incorporation of amino acids.  The transfer mechanism
appears to be extremely effective; during exponential growth observed
amlno acid concentrations in the cell interior are 100 to 300 fold great-
er than in the medium.

Cells which had been in the stationary growth phase for 3 hours, showed
essentially complete removal of amino acids, except for methionine, from
the surrounding medium and from the cell interior.

Based on their results and extensive review of the literature, Kay and
Gronlund conclude that:

     "The enzymatic nature of metabolite incorporation into
     cells, first demonstrated with carbohydrates, has been
     extended in recent years to encompass the amino acids,
     as well as other compounds.  The data presented here
     revealed that the amino acid transport systems of P_.
     aeruginosa have all the properties ascribed to active
     transport systems; the transport process is seemingly
     energy dependent, temperature sensitive, and saturates
     at high substrate concentrations.

     Amino Acids which are transported into P_. aeruginosa
     equilibrate with amino acids synthesized de novo which
     reside in the intracellular pool, and also with amino
     acid pools which have been transiently preestablished
     from an exogenous source.  This demonstrates that, in
     this organism, as in E_. coli and in Neurospora crass a,
     incorporated amino acids equilibrate with, and are
     subject to, the same metablic fates as amino acids
     synthesized de novo.

     The total amino acid pool levels for P_. aeruginosa
     during  exponential growth are of the same order of
     magnitude as the levels reported for E. coli."

It has also been demonstrated that P_. aeruginosa can utilize the maj-
ority of commonly occurring amino acids for growth as either the sole
carbon source or as the sole source of nitrogen  (Journ. Bact. 100,276-
282, 1969).

Utilization of amino acids by activated sludge has been studies by sev-
eral investigators.  Carlson and Polkowski  (Journ. Water Pol. Control
Fed., 34, 8l6, 1962) showed that activated sludges can be maintained on
single amino substrates as the nitrogen source.  Acclimation of the
sludge before exposure to a single amino acid increased rates of met-
abolism, most noticeable with glycine and to a lesser extent with

-------
L-cystlne and L-arginine.  Rate of glyclne depletion was reported to be
48 mg glycine per hour per gram of sludge solids.  This is equivalent to
0.08 wt. % on cell mass per minute and is in reasonably close agreement
with the values reported in the microbiology literature for incorpora-
tion rates.  Malaney and Gerhold (Journ. WaterPol. Cont. Fed., 41, Rl8,
1969) list  a number of studies evaluating the rates of utilization of
amino acids under aerobic conditions.  The individual amino acids show-
ed substantial variations in oxidizability as measured by oxygen uptake.
However, their conclusion is that amino acids can be considered as a
family of similar compounds readily susceptible to biological oxidation.
The reported oxygen uptake is reproduced below:
P       ,                           Percentage of Theoretical Oxygen Demand
ComPQund                          	&	   6hr.  12hr.  24hr.
Aminoethanoic acid (Glycine)                           4.1   8.1    16.9
2-aminopropanoic acid (a-DL-alanine)                  11.7  27.0    43.0
3-aminopropanoic acid (3-alanine)                      1.7   6.9    16.0
2-amino-3-methylbutanoic acid (DL-valine)              2.1   4.3     9-4
2-amino-3-hydroxypropanoic acid (L-serine)             8.6  21.0    29.0
2-amino-3-mercaptopropanoic acid (cysteine)            7,5   8.6    11.2
Dicysteine (Lr-cystine)                                 1.5   2.4     4.7
2-amino-3-hydroxybutanoic acid (DL-threonine)          3.9   8.2    16.2
2-amino-4-hydroxybutanoic acid (DL-homoserine)         l.l   2.3     4.4
2-amino-4-mothylthlo'butanoic   acid (DL-methionine)    1.5   2.4     2.6
2-aminohexanoic acid (DL-norleucine)                   2.3   5.2    12.9
2-amino-3-methylpentanoic acid (L-isoleucine)          2.4   5.3    14.8
2-amino-4-methylpentanoic acid (L-leucine)             1.4   3.6     9.9
2-amino'outanedioic acid (DL-aspartic acid)             8.9  16.2    28.8
2-aminopentanedioic acid (L-glutamic acid)            14.0  25.1    35.8
2-aminobutanedioic amide (L-asparagine)               10.3  19.5    24.7
2-amihopentanedioic amide (L-glutamine)                9.2  19.2    30.7
2,6-diaminohexanoic acid (L-lyslne)                    1.8   4.5    14.1
2-amino-5-quanidopentanoic acid (L-arginine)           2.1   7.7    16.5
2-amino-3-phenylpropanoic acid (DL-phenylalanine)      2.2   5.6    16.4
2-amino-(4-hydroyphenyl) propanoic acid (DL-tyrosine)  3-4   9-7    22.6
1-pyrrolylmethanoic acid (L-proline)                   4.8  13.1    25.5
l-(2-hydroxy) pyrrolylmethanoic acid (L-hydroxyproline)l.O   2.9    18.2
2-amino-3-imidazolypropanoic acid (L-histidine)        2.8   6.3    16.5
                             44

-------
2-amino-3-lndolypropanoic acid (DL-tryptophane)        0.6   1.4     4.6

N-acetyl-2-amlnoethanoic acid (acetylglycine)          9.3  10.0    18.5
Glutamylcysteinylglycine (glutathione)                 5.1   8.2    22.0

The theoretical oxygen demand represents a calculated value based on
complete combustion to COp and ELO.  The low oxygen demand for glycine
as opposed to glutamate is consistent with the notion that amino acids
are utilized for energy, as a source of nitrogen and also incorporated
into cellular protein directly.  The small carbon chain of glycine is
obviously not as readily incorporated into the metabolic pathways as
the larger glutamic acid carbon chain.

Glutamic Acid Utilization

A series of batch tests were carried out to measure rates of biological
degradation of glutamic acid at various feed concentrations.  Innoculum
was obtained from a continuous propagator using 100mg/l glutamic acid
feed solution without any other sources of either carbon or nitrogen.
Concentrated glutamic acid solution was added to each reactor at the
beginning of each test and samples were withdrawn periodically.  The
ninhydrin test was used to measure glutamic acid concentrations and
carbon concentrations were measured independently with the Beckman Car-
bon Analyzer.  Typical decay curves of glutamic acid as measured by nin-
hydrin are shown in Figure 14.  The results show an increasing rate of
removal initially, followed by a decreasing rate as substrate concentra-
tion drops off.  The initial rates are essentially independent of sub-
strate concentration.  Data for carbon concentration follow a similar
trend.  Analysis of the data in terms of the simplified rate equation
for batch systems as described earlier confirms the conclusion that
utilization of glutamate is independent of concentration except at very
low concentrations.  Figure 15 shows that the rate data for carbon re-
moval for all 3 reactors fall on a single straight line regardless of
initial substrate concentration.  The Monod adsorption coefficient (Kc)
has been estimated to be approximately l6mg/l.  This estimate is pro-
bably on the high side because it is based on residual organic carbon
concentration which includes the concentration of nonbiodegradable car-
bon residues.  The corresponding growth rate coefficient is 0.0073 per '
minute and the yield coefficient was measured to be 0.33 grams cell mass
per gram of glutamic acid utilized.  The yield coefficient is consistent
with values reported in the literature.

-------
              FIGURE  14
BIOLOGICAL  DEGRADATION OF; GLUTAMICJ
                    CONCENTRATION
                       ooo    a
-------
              FIGURE  15
I ..... BIOLOGICAL DEGRADATION OF GLUTAMIC ACI0 '
RATE OF
                REMOVAL - EFFECT OF COMCENT(?ATIOM
                     SLOTAMIC AC50 SOSST»?ATE i
                       CONCENTRATION OF
               I..:(.7rX- of ".C"
               I1O    163     100    240


                 TIME ,  MINOTES
                                     280

-------
        Utilization
Glycine was evaluated in a series of tests to determine the effect of
substrate concentration and the effect of acclimation of the innoculum.
Experiment No. 2-20-69 was carried out using innoculum from a continuous
propagator, using glutamic acid as the only source of carbon.  The re-
sults show essentially no removal for the first 6-12 hours .  It is par-
ticularly interesting to note that longer incubation periods were need-
ed when higher initial concentrations of glycine were used.  Carbon re-
moval showed similar trends.  Residual carbon at the end of the test
(after 24 hours) accounted for 26-32$ of the original feed carbon from
glycine.  Rate of glycine utilization was determined using an acclimat-
ed innoculum obtained from 3 continuous propagators using glycine feeds
of different concentrations, 100, 500 and 1000 mg/1 respectively.  (Ex-
periment No. 7-11-69).  Half the effluent from each propagator was milli-
pore filtered to remove cell mass and the filtrate added back.  This
allowed making comparisons of the effect of cell mass concentration as
well as substrate concentration.  The results show that the growth
rate coefficient ( y max) is in the range of 0.0020-0.0049 and the Monod
adsorption coefficient is approximately 80mg/l.  The growth rate coef-
ficient for the acclimated innoculum is comparable to the values observ-
ed for glutamic acid.  However, the high value of the adsorption coeffi-
cient is unusual.  The most likely explanation for this phenomenon is
the presence of protozoa which act as predators and retard bacterial
growth accumulation.  In effect, substrate removal kinetics become lin-
ear after a short initial period of exponential growth.  The subsequent
prey -predator balance results in a uniform rate of glycine removal as
shown in Figure 16 .

As a further check on glycine utilization a -new series of batch tests was
carried out using glycine acclimated innoculum.  Glycine and glutamic
acid concentrates were added in different proportions as shown in Appen-
dix Table 15 (Exp. No. 9-22-69).  The carbon data are summarized in
Figure 17-  Glycine carbon is not utilized as rapidly as glutamic acid
as shown by the slower rate of carbon removal in Reactors A and B.  The
highest rate of removal is observed in reactor C and E where glutamic
acid concentration is 50mg/l.  These data confirm earlier indications
that glycine is not as readily utilized as the larger molecular weight
amino acids .

Protein Chemistry

Proteins are polymers of amino acids which are linked by peptide bonds
between the carboxyl and amino groups of adjacent amino acids.  Ele-
mental  composition tells relatively little of the structure or function
but approximates 45-55 wt. % carbon, 6-8 wt. % hydrogen, 19-25 wt. %
oxygen and 14-20 wt. % nitrogen. Sulfur  and phosphorous are,~also present
in small amounts.  Molecular  weights range from 10,000 to 10 , which
still places proteins in the collodial size range which passes., through
0.45 micron millipore filters.                             ""    ,
                            48

-------
                                                                    \ 6
vo
SOp mg/l..;
•  i  :: :i.. ....'.
(OOO mq/|
... •!. .;.• I  ' ..
fOOO mq/l
:  I     i w
             a co  400
                                                   TIME ,  MINUTES

-------
              FIGURE  17
H T i ,
„ i
} - i >
i ' !
i '
AMI
1 |
NO
A
!
t—
., — _
CID
'!
DIE
ACID  DEGRADATION! WITH! GtyciP^E ;  ACCLI MATED

-------
The protein  used In this work was  obtained from Difco Laboratories
(Detroit, Michigan)  under  the trade  name  Bacto  Peptone.   Typical  com-
position is  listed below:

                                   Wt.  %
Total Nitrogen                     16.16

Peptone Nitrogen                  15-38

Ammonia Nitrogen                    0.04

Organic Sulfur                       0.33

Inorganic Sulfur                    0.29

Phosphorous                          0.22
Ash                                  3.53
                              \
Hydrolysis of proteins yields amino  acids and polypeptide intermediates.
Hydrolysis is mediated by  acids  or alkalies in  boiling water or by cer-
tain proteolytic enzymes.  Enzymatic hydrolysis yields free amino acids.

An excellent review of the proteolitic  enzymes  and hydrolysis of peptide
bonds is presented by Boyer  (The Enzymes  Vol. Ill, Academic Press 1971,
vn-d Vo1- IV» I960,  p. 193).   There 'has  been a considerable accumulation
of information on the mechanism, rates  and products of protein hydrolysis.
Matsubara (as above, p. 721)  points  out that microbial proteases are pre-
dominently extracellular and  can be  isolated from filtrates of bacteria,
molds and yeasts.   Most of the common proteolytic enzymes of animal ori-
gin are present  in the filtrate  from bacterial  and mold or yeast cultures,
including amino- and carboxypeptidases  and a variety of endopetidases.
Lake animal  enzymes, bacterial and mold proteases include enzymes which
are active in acidic, neutral and  alkaline pH.   The majority do not re-
quire activation,  but+s_ome 
-------
Innoculum was prepared in a continuous propagator using lOOmg/1 br.cto-
peptone feed solution.  The innoculum was collected overnight and aerat-
ed continuously.  Concentrates of bacto-peptone and glutamic acid were
added at the beginning of each test to give concentrations in the range
of 120-200 mg/1 protein and 0- 90 glutamic acid.

The results of this test are summarized below:

Initial concentration, mg/1           Growth Rate coefficient, min

Reactor*  Protein   Glutamic acid     Carbon data      protein measure
                                                       ments.
A
B
C
D
E
120
195
260
185
175
0
0
0
47
90
0.0077
0.0087
0.0087
0.0095
0.0101
0.0087
0.003^
0.0034
_ _ _ _
_ _ _ _
* Data from Exp. No. 3-18-69 In Appendix)

Growth rate coefficients were calculated using the simplified form of
the batch reactor equation (zero order substrate kinetics).  This ap-
proach is quite justified because the analysis was limited to the init-
ial part of the test when the substrate concentrations were high.  Com-
parison of the growth rates illustrate that the addition of glutamic
acid increased growth rate somewhat, 10-20%.  The increase in rate ap-
pears to be the result of incorporating glutamic acid into the cell
growth metabolism.  This is illustrated in Figure 18 which compares
protein removal and carbon removal for batch tests which had received
proteins only and mixtures of protein and glutamate.  Batch tests with
glutamate feed show a decidedly higher carbon uptake for a given removal
of protein, indicating that glutamate is being removed from solution.

Glutamate acclimated innoculum was used to evaluate it capacity for
degrading protein (peptone).  Six tests were carried out using 50> 90
and 120 mg/1 of protein and glutamate solution.  The results show es-
sentially no activity for utilization of protein, thus indicating that
this innoculum had lost its hydrolytic activity through acclimation to
glutamic acid as the only carbon and nitrogen source (Exp. No. 3-12-69).
                              52

-------
                                         (8
  *•
  lew
  tec
           T
                                              i
                  £»N  CARSON UTILISATION USING
                                                            FEEDS
|
O
Z
•*
u
o
or
6.
  160
   „
  120
   80
   to
   40
   10
           _j.	
            i •
                                       :NT
                                               3-'8-
                       REACTORS  iA, 5, c  ( NO
                    li  REACTOR  pj...i_
                    I :  ,  :  .  •  I  •  • : . i
                   J4_ .REACTOR   e	L_
                    8—REACTOR  _F_
                    i
                      - T_.
                         -t—
                     :—1_.
     11
          -*>••—i-

                      .._!...
                  zia
                                 -11.4 ._4

                                 _  ^  ,
                                  .	i
                                   i.

                                  ..:j: .

                                  :il
                                      i
                                          t •   t
                                           •M-
                                         _L--.
                                                _:!__.
                                                .^
                                                .:.L
                                                 _.:ON
                                                        T
                                                               _l_J_
                                                       	_(_
                                                              .,.[..,.	L_>_
                                                                  , , . . 1
                                                      ^1-11-
                                         _Lc H e mi C*HL_ co N\ Pp s iTi ON .
                                         :.• l:-•;••:••"••""!"•: r "—T"-i--7t~'|—~"f
                                         ^-N-^-*-lr-f^-:-^-f
                                                 -y
                                                          -L2L.
   _4_v
                                                  ,"~t~
                                                         	[._
           10
                   20
                          30
CO
                                                                     ..A:
                                                                   -f-rf-r-
    -i
^•^•4U
               7*
   60
                                    REMOVED
                                               m9/l
                                53

-------
A similar experiment using an innoculum that had not been operating as
long on glutamic acid showed similar results, except that both glycine
and peptone, were eventually utilized though  at a slow rate.

                         Growth rate       ,        Adsorption coeffici-
Substrate                coefficient, rain."         ent mg/1

Reactor A Glutamic acid       0.0043                   20
Reactor B Glycine             0.002                    34

Reactor C Peptone             0.0001                   	
          Glycine
          Glutamic acid

Observed value for peptone indicates that at the existing conditions,
hydrolysis of proteins was repressed either by preventing the formation
of hydrolytic enzymes or by inhibiting their funtioning.

Milk Solids

A number of investigators have used solutions of milk solids for pro-
cess variable studies.  This is one step closer to simulating munici-
pal waste constituent as compared to the use of pure organic compounds
and mixtures.  Milk solids contain a large variety of organic materials
such as proteins, carbohydrates and minor quantities of lipids as shown
below:

                                   Analysis of Milk Solids - wt. %

Butterfat (lipids)                           0.9

Protein                                     36.9
Lactos e (carbohydrate)                      50,5

Total solids                                96.7
Organic solids                              88.6

BOD (5 day)                                 75(mg/100 mg)
Organic Carbon                              39.2


Milk solids acclimated innoculum was obtained from a continuous propag-
ator using 100 mg/1 feed solution.  Concentrates of milk solids were
added to each of 3 batch reactors and utilization of carbon, protein
and carbohydrate were measured.

The results are summarized in Figure 19.  Initial carbon removal is
Independent  of the concentration of substrate but the rate slows down
as substrate is depleted.  Protein degradation proceeds rapidly and is

-------
essentially complete after 400 minutes.  The residual concentration is
probably the result of small peptides and interferences in' the Folin
test.  It is interesting to note that carbohydrate removal is slower
than protein degradation.  Figure 20 shows the carbon data anaylzed
in terms of the simplified batch rate equation; the results show that
rates of removal are independent of concentration.  Growth rate coef-
ficient (y) is 0.0016-0.0019 per minute and the adsorption coefficient
(Kc) is in the range 18-31 mg/1. based on total carbon.  If the non-
biodegradable carbon is taken into consideration, the value of Kc is
in the range 6-13 mg/1.
                              55

-------
               PK30RE    19
BIOLOGICAL   DEGRADATION  OF MILK  SOUOS
                               REACTORS

                      56

-------
                                                             FIGURE   2O
ui
—3
                   1,00
*»r
                                               Coo
•coo      t2e»
    TIME, MINOTC?

-------
Lipid Chemistry

The term lipid refers to a large group of organic compounds including
fatty acids and their alcohol and sterol esters.  The most prevalent
lipids in municipal waste waters are the glyceride esters and the alkali
salts of fatty acids.

Tne most significant chemical characteristic of lipids is their high car-
bon and hydrogen content and relatively low oxygen content.  Where car-
bohydrates have 40-^5 wt. % carbon, fatty acids have upwards of J0% car-
bon and very little combined oxygen.  The result is that lipids have a
much higher free energy content (available energy) than any other or-
ganic material.  The yields of cell mass per unit weight of substrate
are correspondingly high and the relative amounts of .oxygen needed for
complete oxidation (ultimate BOD) are much higher than those for carbo-
hydrates and amlno acids - proteins.  Lipids are generally deficient
in nitrogen, phosphorous and sulfur and thus resemble carbohydrates.

The role of microbial enzymes in transformation of lipids has been the
subject of extensive research and publication (Microbial Transforma-
tions of Steroids, A handbook by Charney and Herzog, Academic Press
1967; Fatty Acids, Edited by Markley, Interscience Publishers, 196?).
The action of microbial systems includes a wide variety of enzyme cat-
alyzed reactions from oxidations and reductions to isomerization and
hydrolysis.

     "As far as we know, transformations of steroids, carried
     out with intact microbial cells, occur within the cell
     and not in the medium surrounding the cell.  To enter the
     cell the steroid being transformed must dissolve to some
     extent in the medium so that it can diffuse through the
     cell wall and into the enzyme-rich interior.  The prac-
     tical implication of this requirement is that solubility
     and rate of diffusion may become the rate-limiting factors
     for transformation.  Most steroid substrates ordinarily
     employed have modest, though measurable, solubilities in
     water and in the aqueous media used for microbial culture.
     To ensure saturation of the medium and to minimize this
     rate-limiting effect, steroids are often introduced into
     reactions in micronized form or, more conveniently, in
     solution in a water-miscible solvent from which precipi-
     tation in very/fine particles occurs upon dilution with
     the aqueous medium containing the microorganisms.

     The experimental findings may be interpreted reasonably to
     show that microbial enzymes are not highly substrate speci-
     fic.  The alternate explanation for the diversity of sub-
     strates which a given species can transform is that the
     organism has a different enzyme for each new substrate.
     The latter explanation is much less satisfying, and no
     evidence has been adduced in its support."'


                             58

-------
One possible explanation for the nonspecificity of microbial enzymes
is that microbial organisms are also producers of lipids internally and
therefore requires the capability to catabolize lipid materials in the
natural growth cycle.

The hydrocarbon chain and the carboxyl group are the most prominent
characteristics of lipids.  They impart special physical characteristics
which make for.low solubility and surface activity in water solutions.
Solubility in water is a strong function of molecular size, pH and salt
concentrations.

               Solubilities of Fatty Acids in Water
Grams acid per 100
Acid
Caproic
Heptanoic
Capryllc
Nonanoic
Capric
Hendecanoic
Laurie
Tridecanoic
Myristic
Pentadecanoic
Palmitic
Heptadecahoic
Stearic
0°C
0
0
0
0
0
0
0
0
0
0
0
0
0
.864
.190
.044
.014
.0095
.0063
.0037
.0021
.0013
.00076
.00046
.00028
.00018
20
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
°c
968
244
0068
026
015
0093
0055
0033
0020
0012
00072
00042
00029
g. water
30
1.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
°c
019
271
079
032
018
Oil
0063
0038
0024
0014
00083
00055
00034
45°C
1
0
0
0
0
0
0
0
0
0
0
0
0
.095
.311
.095
.041
.023
.013
.0075
.0044
.0029
.0017
.0010
.00069
.00042
60°C
1
0
0
0
0
0
0
0
0
0
0
0
0
.171
.353
.113
.051
.027
.015
.0087
.0054
.0034
.0020
.0012
.00081
.00050
 GJ.  Org.  Chem.,  7,  546,  1942)

 Substantially higher solubilities
 are  obtained in  alkaline solution

               Lithium Salts
of the long carbon chain fatty acids
by salt formation,  (saponification).

 gm/100 gm H90 (25°C)
                Laurie

                ]Y(yristic

                Palmitic

                Stearic
      0.187
      0.036

      0.015
      0.01
                              59

-------
It has been observed that a number of the higher molecular  weight fatty
acids can be dispersed in water in excess of their reported solubility
and maintained in suspension.  One mechanism for such dispersion is
the formation of a thin film at the air-water interface, (frequently
assumed to be a monomolecular film).  This in effect makes the air-
water interface a rich source of organic material and oxygen for those
microorganisms that metabolize fatty acids.  Another phenomenon which
enhances the "apparent" solubility of fatty acids is the fcarnation of
micelles.  Micelles are aggregations of molecules'to form colloids.
According to Jirgenson, micelles are formed by molecules with large
hydrophobia parts and a strongly polar group in the same molecule.
(Organic Colloids, Jirgenson, p.50, Elseier Press  1958).  Arrangement
of molecules is believed to be such that the long carbon skeletons are
parallel to each other with the carboxyl group extending into the sol-
ution in order to minimize water contact.  This type of behavior is
evidenced by decreasing osmotic activity at increasing concentrations
of the hydrophobic material.  Micelle formation is dependent on several
variables, including concentration of the molecular species.  Critical
concentration which leads to micelle formation have been reported.

               Potassium laurate        0.02 moles/1. (26°C)

               Potassium Linoleate      0.0002 moles/1. (26°C)

Fatty Acid Degradation

Three fatty acids were tested, lauric, palmitic, and stearic.  Feed
solutions were prepared by solubilizing the fatty acid in approximately
200ml.   of 1.0, normal sodium hydroxide solution.  This concentrate was
then dispersed rapidly into feed solution (5 gallon batch) which con-
tained all the necessary salts.  The pH was adjusted by adding hydroch-
loric acid.  The resulting solutions frequently developed a cloudy
appearance, Indicating that there was some formation of colloidal
dispersions (micelles).  •

In order to test for colloid formation, the feed solutions were occas-
sionally filtered through millipore filters.  It became apparent that
at the desired concentrations, up to lOOmg/1, only lauric acid solu-
tion remained in reasonable dispersion.  As a result, most of the bio-
degradation studies were carried out with lauric acid.
                     /
                    /
Considerable effort was expended on developing or adapting analytical
procedures for the precise determination of fatty acids at the concen-
trations in question. (0 to 100 mg/1).  Unfortunately, the available
methods are not sufficiently sensitive at low concentrations.  Further-
more, extractions'with fat specific solvents were not quantitative nor
sufficiently reproducible to allow measuring the small changes in fatty
acid content that are obtained in kinetic studies of this type.  As a
result,  it was,necessary to calculate or estimate fatty acid degradation
from carbon removal data and specific analysis for the other substrates
                             60

-------
in order to back calculate removal of fatty acids.

Biological uptake of lauric acid was measured in batch tests using
innoculum from a continuous propagator using 50 mg/1 lauric acid feed
as the only source of carbon.  The innoculum was thus well acclimated
to metabolizing the lauric acid substrate.  Different amounts of fresh
feed solution (50 mg/1) were added at the start of each batch test, and
samples removed periodically for carbon analysis (Experiment No. 10-7-69)
and 10-18-69).  The results show that acclimated innoculum is an effec-
tive biological system for removing fatty acids as illustrated in Pig.
21 which shows the removal of  carbon as a function of time.  The results
were correlated using the simplified batch reaction equation (assumes
adsorption coefficient K is negligible).  The calculated growth rate
coefficient is'0.0037 per minute (25°C), carbon residue was approximately
6 mg/1 and corresponds to 15 wt. % of the initial feed carbon.  Higher
growth rates were obtained in  batch tests which started with higher
dilution ratios of feed to innoculum, up to 0.006 per minute, (Exp. No.
12-18-69 and 12-23-69) reason  for this is not known.  It is unlikely
that substrate concentration is responsible because the calculated
asdorption coefficient (Kc) from these batch tests on fatty acids is
quite low, 7-16 mg/1.  One possible explanation is that the fatty acids
are removed from solution-suspension by adsorption on the biomass sur-
face and are therefore not as  readily available for ingestion into the
microbial cells.

A similar series of batch tests (Exp. No. 12-23-69) using palmitate
acclimated innoculum shows similar results.  The calculated growth rate
for these tests in the range of 0.0057 - 0.0064 and the adsorption co-
efficient K is 7-16 mg/1.  The average value of the calculated yield
of cell mass is 95 wt. % based on carbon removed.  The carbon residues
were very low, indicating that substrate was almost completely removed
from solution.  Initial rate data using palmitic acid feed solution may
not be reliable because there  is some evidence that palmitate was re-
moved by the millipore filters prior to analysis.  Innoculum which was
acclimated to lauric acid feed (50 mg/1) was contacted with feed concen-
trates of glucose and glutamic acid in a series of batch tests (Exp.
No. 12-30-69 and 1-29-70).  The results show that the microbial pop-
ulation is capable of metabolizing these substrates without any dif-
ficulty and without any lag.   Figure 22 shows the removal of carbon;
the initial rate is independent of total carbon concentration and
substrate added.  The initial  growth rate coefficient is 0.0065 per
minute. , However, it is interesting to note that the -calculated values
of Kc are higher for the batch tests which had received glucose and
glutamic acid, 6 mg/1 for Reactor A using only laurate and 40-50 mg/1
for the mixed feeds.  This suggests that the lauric acid acclimated
microorganism population does  not proliferate as well where lauric acid
is no longer available.  Further evidence for this is shown in Figure
23 which summarizes the data for removal of glucose and glutamic acid
measured independently.  It is interesting to note that the removal of
glutamate begins 200 minutes after the start of the test and glucose
                             61

-------
                FIGURE"   21
 FATTY ACID  DEGRADATION - CARSON
                            a   RE/HCTOR *
                            •   REALTOR R
                            *   RETACTOR C
                            +   REACTOR D
                            O  REACTOR E
                            X  REACTOR F
t , \ B t I . I t ( . n r . i . . . i -i r FT T - .  . L . | f r n . . t r i [r r	I - [r [r r j r I I I f  - I	' t	*)-. - -i I  rlilrri) ••i^.j^X . . i H L I [  I n > -4 • • •
             ''
                                                cct
                TIME ,
                     62

-------
             FIGURE  22
DEGRADATION  OF  MIKED  FEED SOLUTION BY
    LAURATE ACCLimATED  INNOCULC/A/t
         REACTOR
            A
            B
            C
            D
LAUl$!C ACIP
       -I-
       4- 6LUTAMATE

      t 6LUCOSE 4
              TIMS, MINUTES
                 63

-------
                         FIGURE   23
        R£MO\/Al.  OF ©LUTAMATS" AMD GLUCOSE
            LAURATE  ACCUMAT£f>
jcc Stic  iccc  n<>o  I2oc  lice
       106   260  VCO  4CO  ?CC
o
                       TIME ,

-------
removal is delayed for 300-400 minutes.  Thus lauric acid was removed
preferentially and the other substrates were utilized only after most
of the lauric acid substrate had been consumed.  The utilization of
glutamate before glucose is especially noteworthy.  The batch tests
were fed with a nitrogen limited solution so that this may account for
some preferential uptake of glutamate, however, it is also evident
that glucose was not used until most of the glutamic acid was degraded
so that the nitrogen deficiency is not the whole answer. ,

Additional tests using innoculum from a propagator using mixed feed
solutions were carried out (Exp. No. 2-23-70, 4-30-70, 6-19-70, and
7-15-70).  Concentrates of lauric, glutamate and glucose were added
at the start of each batch test.  To overcome the nitrogen deficienc-
ies observed in some tests, Exp. No. 6-19-70 and 7-15-70 were mod-
ified to include a source of ammonium ions when glucose or laurate
concentrates were added.  Figure 24 shows the removal of carbon when
mixed feed innoculum is exposed to lauric acid, and glutamic acid
alone and in admixture.  Initial rates of removal are essentially
equivalent; carbon concentration drops off to approximately 30 mg/1
in less than 600 minutes except for the mixed substrate.  It is
also noteworthy that the residual carbon level remains high (30 mg/1)
even after 100 hours.  Comparison of the rates of glucose, and glu-
tamic acid removal show that the latter is used preferentially over
glucose, Figure 25.  This holds for the pure substrate tests as well
as the mixed feed test.  Furthurmore, the removal of lauric acid is
at least as fast as the other substrates.  The more gradual removal
of carbon from the mixed feed test finds a parallel in the more
gradual removal of glucose shown in Figure 25.
                              65

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   FIGURE  24
M
-------
            FIGURE  25
              FEED  INN0CULUM
    GLUCOSE AND 6LUTAJAATE
                      •   REACTOR  6
                      *   REACTOR  C
                      4   REACTOR   0
                                  i«c
TilV»e , MINUTES
                                        tec  icO
                                TIMC, MIMUTES
                   67

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Rate Studies Using Treatment Plant Biomass

A series of batch tests were carried out using activated sludge from
the Minneapolis-St. Paul Sewage Treatment Plant.

The tests were designed to evaluate the activity of activated sludge
biomass and to measure the relative rates of removal of the three major
categories of substrate, namely carbohydrates, proteins and lipids, (Exp.
Nok 7-23-70 and 8-11-70).  Activated sludge was taken at the plant just
prior to the tests.  Concentrates of various substrates were added at
the start of each test.  Samples were withdrawn for analysis as pre-
viously described.  Experiment No. 8-11-70 consisted of 7 batch tests
each starting with 200. ml of dilute activated sludge (492 mg/1 sus-
pended solids).  Concentrates of pure substrates were added as shown
below.

                    Volumes of Concentrate Added*, ml.
Glucose        Starch    Glutamate      Peptone   Laurate   Reactor

i|0             	      	        	     	       A

	           40        	        	     	       B
^ _ _          	       1|0            	     	       C
i. - -       '	      	         40       	       D
_-_          	      	        	      160        E

20             	       20            	       40        F
u A* _           20        	         20         40        G

*1QOO mg/1 except for laurate which was 100 mg/1 as lauric acid.

Comparison of the concentration versus time profiles of each substrate
and carbon gives some insight on the relative rates of removal and the
ability of the biomass to handle single substrates in large doses.  A
second batch of concentrate was added after 400 minutes and substrate
removal measured for an additional 1000 minutes.

Analyses of the carbon data shows that glucose was removed more
rapidly than any other substrate.  Glutamate was removed rapidly after
the second addition of concentrate but showed a lag during the first
part of the test.  The most rapid removal of carbon was noted with the
mixture of glucose-glutamate-laurate.  By contrast, degradation rates
of the colloidal substrate, starch and protein, were slower in both
parts of the test.  Data for glucose removal are shown in Figure 26.
Glucose is removed completely and at a constant rate from the beginning
of the test.  Figure 27 shows the corresponding data for amino acids.
Removal rates are more variable.  The gradual increase in amino acid
concentration in Reactor G is probably the result of hydrolytic degra-
dation of proteins to form amino acids which are subsequently removed
                             68

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by the biomass.  Removals of starch and protein are summarized in Fig.
28 and 29 respectively.  The rates of removal after the second addition
of concentrate are higher in each case, suggesting that the sludge as
received is not sufficiently acclimated to hydrolyze colloidal substrates
at high rates.  The slow rate of colloid degradation seems surprising
because municipal sewage has some 50% suspended material of which half
is settleable and half is in the colloidal size range.  One possible
explanation for the hydrolytic activity may be the prior history of the
recycled sludge biomass.  Free exoenzyme being relatively small colloids,
molecular weights of 100,000 or less, are more likely to be carried out
with the effluent from the  final sedimentation tank.  Ihe hydrolytic
enzymes associated with the cell surface are frequently subjected to a
period of endogenous metabolism in the final sedimentation tank and in
the latter part of the aerator itself where the detention time is long.
                              69

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                       26
GLUCOSE REMOVAL £y ACTIVATED  SLUDGE

                          •  REACTOR A
                          X  REACTOR F
           |OC
              TIME ,
                    70

-------
       FIGURE  27
AMINQ ACID REMOVAL
ACTIVATED SLUDS£ BlOMASS
                REACTOR C
                REACTOR P
                REACTOR F
                       G
           71

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        FIGURE: 28
  STARCH  REMOVAL BY
ACTUATED SLUO6E
                              8
                      REACTOR (5
                          ICO
       TIME, MINUTES
           72

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    FIGURE  29
ACTIVATED 5UID6£
       73

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Measurement of the. Rate of Oxygen Uptake of'.Sewage Solids

This experiment was designed to measure the rate of oxygen uptake re-
sulting from the addition of typical raw sewage solids to a typical
mixed liquor activated sludge innoculum.  Parallel experiments were
carried out to measure oxygen uptake using mixtures of soluble sub-
strates (glucose and glutamic acid) and colloidal substrates (peptone
and starch) and aliquots of the same innoculum.  Tests were carried
out in a 1.5 liter enclosed vessel.  Oxygen determinations were made
using a dissolved oxygen electrode probe; samples were analyzed for
organic carbon.

The sewage solids were obtained by centrifuglng primary effluent from
the Mlnneapolis-St. Paul Treatment Plant.  The solids were collected and
autoclaved for 10 minutes and stored under refrigeration until use.
Prior to the test the solids were treated in a blender for about 5 min-
utes to disperse large flocculated material and to reduce particle size
somewhat.  Feed concentrates of glucose, glutamlc acid, peptone, and
starch were also autoclaved prior to use.

At the beginning of each test, sewage solids or fresh feed solutions
were added as shown below:

     Reactor A - 2.0 liters mixed liquor; no feed added, mixed liquor
                 suspended solids concentration was 1,330 mg/1.

     Reactor B - 1.5 liters mixed liquor, added 0.25 liters each of
                 1600 mg/1 concentrate of glucose and glutamic acid,
                 mixed liquor suspended solids concentration was 890
                 mg/1.

     Reactor C - 1.5 liters mixed liquor, added 0.25 liters each of
                 1600 mg/1 concentrate of peptone and starch, mixed
                 liquor suspended solids concentration was 875 mg/1.

     Reactor D - 1.5 liters mixed liquor, added 0.5 liters of sewage
                 solids obtained from centrifugation of raw sewage,
                 mixed liquor suspended concentration was not determined
                 after solids addition but was calculated to be 860 mg/1
                 based on the innoculum alone.  The solids alone had
                 a suspended solids concentration of 2,715 mg/1.

     Reactor E - 2.7 liters of mixed liquor from composite of reactors
                 B, C, and D, added 0.1 liters each of 900 mg/1 glucose
                 and glutamic acid solution.

     Reactor F - 2.7 liters of mixed liquor from composite of reactors,
                 B, C, and D, added 87.5 ml. of sewage solids.

The mixtures were aerated and agitated continuously except for the time
during which oxygen measurements were carried out.  The mixture was
transferred into the special reactor and oxygen determinations were made

-------
continuously usjjig a strip  chart  recorder.   The  rate  of oxygen consump-
tion was then determined from the strip  chart  recordings.  Sarrples were
also removed and total organic  carbon measured for each oxygen consump-
tion test.

Oxygen uptake rate expressed as milligrams  of  oxygen  consumed per hour
per gram of suspended solids as a function  of  time in minutes are shown
in Figure 30, the corresponding organic  carbon concentrations are shown
in Fig. 31.  Reactor A represents the base  case  mixed liquor activated
sludge without any extraneous addition of fresh  substrates.  The oxygen
consumption rate remains fairly constant at about  10  milligrams per hour
per gram of suspended solids.  By constrast both reactors B and C show
a marked peak after the addition  of fresh substrate.  Oxygen uptake in
Reactor C using collodial substrates  (Peptone  and  Starch) are approximat-
ely the same as for Reactor B using soluble substrates  (glucose and
glutamic acid).  This suggests  that mixed liquor contains sufficient
concentrations of hydrolytic enzymes to  convert  colloidal materials
into assimilable soluble substrates. Reactor  D  which received the sew-
age solids additionally showed  the highest  oxygen  uptake rate.  This is
particularly surprising in view of the fact that the  dissolved carbon
of Reactor D was if anything somewhat lower than Reactor C.  One possible
explanation for this observation  is that the sewage solids contain a broad
range of substrates which  favor growth of a large  variety of microorgan-
isms, such as are found in sewage.  By contrast  it may  be that speciali-
zed substrates, such as pure compounds,  may be restrictive in the spec-
ies that can thrive immediately on the limited substrate variety.

Test results using mixed liquor from an  activated  sludge plant as in-
noculum show that there is sufficient enzyme activity to degrade col-
loidal materials  (as measured by  oxygen  uptake).  Tnis  conclusion is
based on the observation that the addition  of  colloidal substrate gave
approximately the same rate of  increase  in  oxygen  uptake as when soluble
substrates were added.  Tne initial dosing  of  food materials is consum-
ed during the first few hours but then levels  off  leaving a large resi-
due of organic carbon in solution.  Oxygen  uptake  rate  also levels off
but continuous for more than 20 hours without  any  substantial changes
in dissolved organic carbon. The results indicate that continuous
aeration leads to endogenous respiration of the  cell  mass but does not
reduce the dissolved organic carbon concentration  of  the liquor to any
appreciable extent during  the first 20 hours or  more.
                              75

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CT\
                                 RAT£ OF i ACTIVATEo
                                    SEWAGE ! SOUOS
                                                                           3.COC

-------
           Me
     FIGURE  31
2s:
2w
           FOR
MEM
                                 : .  ^^ ^^   ^^  —^^^ '^ ^MB - ^k ^B • -i ............. ; - - - - I • -t 	
                          CARBON  CONCENTRATION
                                        SOUOS
                                                     REACTOR
                                                     REACTOR
                                                     REACTOR
                                                  +  RCACTOR

                                                  o
                                                  X

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FILM FLOW REACTOR TEST'RESULTS

There Is. growing interest in the quantitative, description of biologically
mediated reactions In connection with, waste, water treatment and natural
purification of waters.  IVbst of the published data in this field concerns
well mixed reaction systems in which, the active cell mass Is suspended
in the growth medium by agitation.  Relatively little Information is
available on the kinetics of stationary, biologically active surfaces
(slime layers).  Stationary slime layers are important in at least two
areas; namely, in the trickling filter process for sewage  treatment and
in the attached biomass of stream beds.

This section describes results of studies using fixed biologically ac-
tive slime layers to determine the kinetics of removal of organic sub-
strates.  The substrates were chosen with a view to simulating the maj-
or constitutents of domestic waste water; namely, carbohydrates, amino
acids-proteins, and fats.  The immediate objective is to provide a better
understanding of the trickling filter process in sewage treatment.  How-
ever, the approach and results may be of general interest in biological
processing.
MASS TRANSFER CONSIDERATIONS IN BIOLOGICAL TREATMENT

It is generally recognized that there are many similarities between
enzyme kinetics and heterogenous chemical reaction kinetics.  Reactants,
intermediate adsorbed species and product species can be defined and
measured.  By contrast, the biological activity of whole microorganisms
is much more complex.  Mcrobial metabolism is the sum of thousands of
enzyme catalyzed reactions, simultaneous and sequential, dependent and
Independent of each other.  Nevertheless, it has been found useful to.
apply some of the concepts of heterogenous catalysis to evaluate biolo-
gical kinetics; namely, mass transport of substrate to the active sites
and adsorption and reaction at the surface.  In heterogenous catalysis,
mass transfer limitations are likely to occur when, (a) concentration of
reactants is low, (b) catalytic sites are inaccessible to bulk flow, and
(c) potential reaction rate is high.  Liquid phase reaction systems are
frequently limited by mass transfer because diffusional transfer through
the boundary layer is very slow.  Some of the same conditions prevail
in biological,waste water treatment systems such as trickling filters
and to a lesser extent in the floe particles in activated sludge treat-
ment.

A number of investigators have shown that biological reaction  rates
are limited by the availability of either substrate, oxygen, or salts.
Rashevsky (Mathematical Biophysics; volume I; page 36,  Dover Press) has
described an analytical model for a spherically shaped microorganism
Immersed in a bulk fluid.  The model describes concentration gradients
                             78

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in the exterior boundary layer of the  cell assuming that the layer is
stagnant and mass transfer is by molecular diffusion.  Mueller, Boyle,
and Lightfoot, (21st Purdue Industrial Waste  Conference, May 1966)
studied the effects of floe size in a  wen mixed agitated reaction vessel
to simulate the conditions obtained in activated sludge aeration tanks.
For dispersed cells of Zooglea ramigera, minimum oxygen concentration
for uninhibited growth was found to be 0.1 mg/1.  For floe particles,
minimum 02 concentration was 0.6-2.5 mg/. depending on floe size.  Re-
sistance  to oxygen mass transfer in the liquid film surrounding floe
particles was negligible compared to the resistance within the clump
of cells.

Studies using fixed slime layers to simulate  some aspects of trickling
filter operations have been reported by several investigators.  Gulevich
(Johns Hopkins diversity Report, Jan. 1967)  used rotating disks covered
with biological slime and immersed in  feed medium.   Glucose uptake rate
was found to be a function of the velocity field.  Hartmant (J. Wat.
Poll. Control Fed., 39, 958, June 196?) used  a tubular reactor coated
with biological slime and measured the effects of flow rates on oxygen
consumption.  The results show that increasing the velocity increased
oxygen consumption, except at very high flow  rates.  He ascribes this
to increased mass transfer from the bulk  fluid to the slime layer.
Swilley (Riee University Report, Feb.  1965) and Maier (San. Eng. Div.,
ASCE, SA4, p.91, Aug. 1967) used a flat surface slime layer to study
biological uptake of glucose from medium percolating over the slime in
a thin film.  These studies have demonstrated that mass transfer limits
uptake at low concentrations.  The slime layer-film flow reactor data
have been considered in the light of analytical models patterned  after
the film flow reactor models used in heterogenous catalysis.  A der-
ivation and solution for the flat plate reactor has been published by
the author (Thesis, Cornell University, Sept. 1966) and will not be
repeated here.  The model allows making predictive statements about the
maximum amount of substrate available  at the  slime-liquid interface
as a function of flow rate, slope of surface, substrate concentration
in the bulk liquid phase and substrate type.   This model has also been
used as a reference point for the studies to  be described below.
BIOLOGICAL SLIME LAYER

Most of the literature discussion of slime layers is with reference to
trickling filters.   Holtje (Sew.  Works Journ.,  15,  14,  Jan.  19^3) has
described the  development and species composition of slime layers in
trickling filters.   Tygically, the slime consists of large numbers of
microorganisms (3 x 10 cells/cm^); a large variety of microorganisms,
namely  bacteria,  fungi, protozoa, and higher forms of life have been
identified. Popluation distribution and density reflects environmental
conditions such as  composition and concentration of wastes,  temperature,
and hydraulic  loading.  Surface growth starts with the  attachment of
                               79

-------
zoogleal bacterial at the solid surface.  Wattle (Sew. Works Journ.,
15, 476, 1943) has described the cultural characteristics of pure cul-
tures isolated from trickling filter slimes; they, are gram negative
short rods, enmeshed in a gelatinous mass.  Their characteristics.are
similar to Zooglea ramigera as described in Sergey's Manual of Deter-
minative Bacteriology"  Hawkes (The Ecol. of Waste Water "Treatment,
McMillan Co.,,1963) has published the most comprehensive- description
of the ecology of slime layers.  It has been suggested that bacterial
slimes form a gelatinous matrix which acts as a binder and holds the
bacteria together.  The slime layer thus provides a habitat for other-
species.  Filamentous forms such as Sphaerotilus and Beggiatqa are
frequently present.  Nitrite and nitrate producing bacteria build up,
given sufficiently long residence time.  The occurrence of fungi depends
on operating conditions.  .Since bacteria and fungi are. in competition /-
for soluble substrates, the bacteria generally predominate except at
unusual pH.  It is believed that the development of protozoa is closely
tied to the bacterial population • on which they feed.  However, Brink
(Intl. Rev. Gas. Hydr. 52, 1, 1967) questions the importance of bacteria
as food sources for protozoa and suggests that ciliates feed mainly on
dead organic matter.  Higher forms of life, such as worms and insects
are considered to be. secondary feeders in that they derive their nutri-
ents from the degradation of other microorganisms.  The thickness of the
biological slime layer varies from a few microns to 0,5 cm; the steady
state thickness depends on hydraulic load and availability of nutrients.
Bacteria predominate at the liquid interface where there is direct ac-
cess to soluble and colloidal nutrients..  Fungi and filamentous forms
predominate in the inner layers next to the solid support.

During the last few years a number of investigators have studies the
kinetics of biological surfaces under more controlled conditions -in .
order to obtain more detailed descriptions of,the effects, of operational
variables and to allow .making more precise measurements of the effective
slime thickness.  Sanders (Air and Water Poll., Int. Jt, 1(D,,235) stud-
ied the attachment and formation of slime layers on submerged, surfaces
in a flow system using nutrient broth medium.  He reports a value,of
10 microns (10   cm) for the average thickness of the first ^ attaching
layer of microorganisms.  Thickness increases with time, but a steady
state rate of oxygen utilization was observed after the slime^ thickness
reached a depth of approximately 20 microns.  The limiting thickness
(just prior to complete break away) varied from 80 to 400 microns.  It
is clear that the slime layer is not a smooth and uniform- surface.
Sanders reports topographical variations of the same order of magnitude
as the average thickness of the slime layer.  The slime is periodically
torn away from its attachment (after about two weeks) and the build up
process starts anew.  Bulk flow velocity has the expected effects; low
flow rates (O.lft/sec.) ultimately result in thicker slime layers where-
as higher flow rates (1.Oft/sec_.>increase the maximum uptake rate, of
oxygen from 38 xlO   to.68 x 10   milligrams per minute per centimeter
squared of surface.
                             80

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The Stevenage Laboratory  of the  Institute  of Sewage  Purification
(1956 Report) has run tests using a rotating cylindrical  surface to
measure, the effect  of slime accumulations  in sewage  treatment.  Iheir
data show that the  rate of purification increases, with increasing slims
mass until an amount equivalent  to a thickness of 0.012 cm. has built
up.  Further accumulations had no effect on the rate of uptake of nut-
rients.  Komegay and Andrews  (J. 'Wat.  Poll.  Control Fed., ijp_, R400,
Nov. 1968) report that the maximum effective thickness of slime in an
immersed film reactor is  approximately  70  microns.   In a  study using
a flat surface slime layer, the  author  showed that increasing, slime
thickness In the range of 0.05 to 0.2 centimeters had no  effect on glucose
uptake rate.  The measured rate  of glucose uptake has been compared with
uptake rates measured in  well  mixed reaction vessels to allow estimating
the effective thickness of the slime layer.  A cell  size  of 0.5 to 1.0
microns was assumed.  The results indicate that an active layer of one
to two cells could  account for the observed glucose  uptake rate.

Studies of a number of investigators confirm the conclusion that the
biological activity responsible  for substrate uptake is localized in a
thin film at the interface between the  slime layer and liquid film.  This
lends support to the idea of modeling the  behavior of the slime layer in
terms of a catalytically  active  surface akin to heterogenous  catalysis
in a film flow reactor.
 FILM FLOW REDACTOR—OPERATING PROCEDURE

 A flat  inclined plane, illustrated in Figure A-l (Section A) was used
 as a support for the slime surface.  The plate, 60 cm.  long and 11  cm.
 wide, was covered with a wire mesh as a framework to' hold the  slime layer
 in place.  Growth medium was passed over the surface in a thin film.
 The surface was scraped periodically with a knife edge  to remove cell
 rass and ensure uniform slime thickness.  Scraping did  not  affect the
 rate of uptake of substrate,  Feed and effluent samples were tested to
 determine substrate removal.  Samples were collected over a period  of
 1 - 10  minutes and filtered through a 0.^5 micron millipore filter  to
 remove  active 'cell material.  The surface was allowed to equilibrate for
 at least 30 minutes after each change in operating conditions. Previous
 experience' has shown that this was more than adequate to achieve steady
 state provided that there is no need for acclimatization of the cells
 to a new substrate.  The data are listed in Appendix Tables 29-34-
 STARCH DEGRADATION

 A'''slime layer was grown using a feed solution containing 100mg/l._ starch
 as  the only source of carbon, and salts.  The original microorganism
 seed was obtained from the Mlnneapolis-St.  Paul Sewage Treatment Plant.
                              81

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Four levels of starch concentration were tested at various flow rates
ranging from 1 to 75 milliliters per nimute per centimeter of plane
width.  Starch concentration was determined colorimetrlcally using
iodine reagent and the Beckman Carbon Analyzer was used to determine
organic carbon as described in Section A.

Typical results using soluble starch are shown in Figure 32, where
effluent concentration is correlated with reciprocal flow rate.  Efflu-
ent concentration was found to vary inversely with flow rate.  This is
in accord with earlier observations using glucose which showed that the
quantity of substrate removed is essentially independent of flow rate.
It follows that the slope of the correlation lines is a measure of the
rate of substrate uptake.  Increasing feed concentration from 20 mg/1
starch to 50 mg/1 more than doubles the slope and the rate of starch
degradation.  A smaller increase was observed for the 100 mg/1 liter
feed, while above 100 mg/1, there was essentially no change in slope.
These data are summarized in Figure 33, the rate of substrate degrada-
tion is expressed as milligrams per square centimeter of slime surface
per minute and is correlated with feed substrate concentration.  The
measured rates of starch removal are compared with the rates of starch
mass transfer calculated from the diffusion control model.  A value of
0.08 cm /sec. was used for the molecular diffusion coefficient of starch
is water at 20°C.  There is close agreement up to 50 mg/1 feed concen-
tration.  At higher feed concentrations, the measured rates of degrad-
ation- level off and become independent of feed concentration.  Starch
degradation in excess of that calculated by the mass transfer model was
observed occasionally at low concentrations.  This is believed to be
due to the counter diffusion of hydrolytic enzymes and cells from the
slime surface into liquid film.  Spot tests show that there was contin-
uing degradation of starch in the receiving vessel at rates of 0.1 -
0.2 milligrams per liter per minute.

Removal of organic carbon proceeds at a slower rate than starch de-
gradation.  Nevertheless, the effect of feed concentration follows the
same pattern, carbon removal increases with feed carbon concentration
then levels off at high feed concentrations.

The observed pattern of starch degradation and organic carbon consump-
tion lend support to the explanation that starch degradation is mass
transfer limited at low concentration and reaction rate limited at
higher concentrations.  The slime layer behaves like a catalytically
active surface which catalized hydrolysis of starch colloids into
soluble fragments; part of the solubilized carbon is consumed  while the
remainder diffuses back into the liquid film.

Measured carbon uptake accounts for less than 50% of the degraded starch
at feed concentrations above 50 mg/1 of starch.  The difference between
rate of carbon uptake and starch degradation indicates that these pro-
cesses occur independently and  possibly at different locations on the
surface.  The presence of hydrolytic activity in the liquid film (with-
out any measurable carbon removal gives further support to this explana-
tion.


                             82

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                           Figure  32


                  Starch Concentration Versus Plow Rate
   160
   140 I
u
z
O
o

I
u
o:
LO

       0
,04
.08     .12     .16

  1/FLOW  RATE
                             83

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                Figure 33
     Starch Degradation Versus Feed Concentration
20    40    60    80   100   120   140
   SUBSTRATE  CONC.  mg/l

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GLUCOSE-STARCH. MIXTURES

Mixed feed solutions of  starch  and glucose were tested to determine
the behavior of the slime  layer In the presence of both colloidal and
soluble substrate.  A  slime  surface,  which had been acclimated to feed
solutions containing starch  as  the only  source of carbon, was used.
Feed and effluent samples  were  millipore filtered then analyzed for
starch, organic carbon,  and  glucose.  Glucose  was measured colorimetri-
cally using an enzyme  reagent available  from Worthlngton Biochemical
Corporation under the  trade  name Gluostat.   The test sequence was start-
ed with a lOOmg/1 starch feed followed by mixtures of starch and glucose,
glucose alone and finally  a  mixture.  Each feed was evaluated over a ran-
ge of flow rates.  However,  the quantity of  substrate removal was essent-
ially independent of flow  rate  and uptake rate was expressed in terms of
milligrams per centimeter  squared per minute.  Measured rates of removal
of starch, glucose, and  organic carbon are summarized below.

Peed      Feed Concentra-  Carbon Concentra-   Rate of Removal*-
          tipnmg/1        tion  mg/1          mg/cm -min.xlO          Test
Starch Glucose
Starch
Starch
Glucose
Starch
Glucose
Glucose
^W-MMMMMIIBwi-^VIMMMHM^V
Glucose
Starch
107
105
53
100
99
100
98
48
44
64

82

45
	 	 — — —
63

309
330

267

132

_ _ _
190

362

380
320

Carbon
52
129

154

170
~~161

1
2

3

4
—

Addition of glucose had no immediate effect on the  rate of starch de-
 gradation   Tests #2 and #3 were carried out over a period of 4-5 hours.
However, addition of glucose did increase the rate  of organic carbon
uptake by a factor of 2-3.  Glucose uptake was nearly doubled by using
a feed concentration of 100 mg/1 compared to 50 mg/1  in Test #2. How-r
ever, the rate  of glucose and carbon uptake remained  essentially con -
stant when  starch was deleted during Test #4.  At the end of Test #4
('about 3 hours),  starch was reintroduced at 50 mg/1 concentration.
Starch degradation was observed, but the rate was 1/3 of that observed
earlier.  The reduction is larger than expected for this change in feed
concentration and it seems likely that some of the  enzyme activity was
lost during Test  #4 when growth was fueled by glucose alone.

Comparison  of the rates of carbon uptake versus glucose uptake shows
that glucose is almost completely consumed.  By contrast, only a fraction
of the degraded starch is consumed, less than 40$.  These observations
                               85

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are consistent with the concept of a surface. which, has catalytic
activity for both hydrolysis and carbon uptake and where the active
sites are independent and physically separated.  The. marked increase
in carbon uptake observed when glucose was added along with starch
clearly shows that the carbon consigning activity was not fully ut-
ilized when starch was used.  It seems plausible that carbon uptake
is limited by the transport of the products of starch hydrolysis to
the active carbon consuming sites.  Such transport would have to be by
molecular diffusion, which would account for the. low rate of carbon
uptake as well as the "loss" of hydrolysis products into the main liquid
film.
AMINO ACID AND PFDIEINS.
Experimental work using glutamic acid, glycine, peptone, and mixtures *
was designed to establish the difference in rates of uptake of soluble
and colloidal substrates.  Bacto peptone and bacto agar (Difco) were
used as a source of peptones.  Amino acids were measured with ninhydrin
as described in Section A.  This test is both sensitive and reproducible
but interpretation of the results is difficult because ammonium ions
also react with the reagent.  Protein was measured using Folin Phenol
Reagent.  The reagent reacts with reducing groups in proteins to give
misleading results with partially hydrolized proteins.  Organic carbon
was measured to determine complete uptake.

In the first test, a glutamic acid feed solution (100 mg/1) plus salts
and buffer was used to grow an acclimated slime layer using seed from
the Minneapolis-St. Paul Sewage Treatment Plant.  Pour feed concentra-
tion levels of glutamic acid were tested at various flow rates.  As
with the starch tests, the quantity of glutamic acid removed was found
to be independent of flow rates and the rates have been expressed in
terms of mg/cm -rain.  Carbon rate data are shown in Figure 34 as a fun-
ction of feed carbon concentration.  Calculated rates of carbon trans-
fer' using the diffusion control model are shown for comparison.  A
diffusion coefficient of 0.63 x 10   cm /sec. was used for glutamic
acid in water at 20°C and a carbon content of 40.8 wt.% was assumed for
glutamic acid.  Measured rates of carbon uptake increase with increasing
feed concentration but level off at concentrations about 40 mg/1.  Up-
take of carbon is many fold less than that calculated from mass trans-
fer considerations.  Nevertheless, the initial effect of feed concentra-
tion, suggests that mass transfer is a limiting factor at low concentra-
tions .

The corresponding rates of disappearance of glutamic acid  (measured with
ninhydrin) are nearly independent of feed concentration.  It appears that
this is due to the interference of ammonium ions in the test and does
not necessarily reflect the kinetics of the reactions.
                             86

-------
                  Figure  34

              Glutajiic Acid-Carbon Removal
                              .
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360
320 i
280
240-i~
      MASS  TRANSFER MODEL
      CARBON
200
   0
20   40   60   80  100

    CARBON CONC. mg/l
                    87

-------
When a glutamic acid acclimated slime layer was exposed to. a solution
containing glyclne as the only carbon source, there was essentially
no uptake of glyclne and no uptake of carbon.  Furthermore, when mix-
tures of glycine and glutamate were used, the uptake rate  was essent-
ially that of glutamic acid.  It appears that the microorganism pop-
ulation was unable to metabolize glycine.  Mien peptone was substituted
for glutamic acid, degradation of peptone and consumption  of carbon  was
observed as shown 'below.                                       •
                                                           ?          —6
p   ,        Concentration, mg/1    Substrate Removal,mg/cm -min x 10
              feed   carbon             carbon       "Protein
Glutamic
acid          110     46                 213
Peptone       200     91                 120           466

Mixture*      - -     69                 213            80

*50~50 mixture

Carbon removal for the peptone feed was less than that observed with.
glutamic acid.  Mixed feeds  (glutamic + peptone) showed higher carbon,
uptake than peptone alone.  However, the slime layer had surprisingly
high activity for removal of peptone as measured- with Polin Phenol re-
agent.  The measured rate of protein disappearance (460 mg/cm -min,.) is
if anything somewhat larger than that predicted  from mass transfer'con-
siderations (340 mg/cm  min.), using a diffusion.coefficient of 0.056 x
10~DcmVsec for  proteins  in water at 24°C.  This'high proteolitic activity
was not observed in all cases.  It appears that  under certain (as yet
undefined conditions) a glutamic acid acclimated* slime layer may have
very little initial proteolitic activity.
                                                                is--'
Slime surface acclimated to protein substrate as its only carbon.1;'source.
is capable of shifting to the use of glutamic acid or mixtures of glut-
amic and protein without any reduction in organic carbon uptake..  If
anything, there appears to be a slight rate enhancement with glutamic
acid as shown in the tabulation below:
                                                            2         -6
            Concentration, mg/1     Substrate Removal, mg/cm -min x 10   •••.
              feed   carbon             carbon         protein

Protein       128       53                1?4       .   • 373-**

Glutamic                            '      ....
acid           97       49                200

Mixture       - -       47                160           173

                                                              !
The observed disappearance of protein is in excess of that calculated,
from mass tmasfer considerations using a diffusion coefficient of 0.056  x
10  cm /sec.  Carbon removal is essentially equivalent to protein removal

-------
and indicates that mostly protein hydrolisates  are  consumed as they are
formed, and only small amounts  diffuse  back into  the  liquid film   When
peptone,- feed concentration was  cut in half,  the rate  of disappearance
was reduced proportionately.  This effect  of ..feed concentration is In-
dicative of a mass transfer  limitation.

In comparing the kinetics of removal of glutamic  acid and protein, it
is interesting to note that  glutamic acid  shows evidence of mass trans-
fer limitation even  though the  diffusion coefficient  is some 10 fold
larger than that of  proteins.  Glutamic acid removal  is less than 30$
of the maximum calculated from  mass transfer.   Whereas, observed protein
degradation rates are of the  same magnitude as  calculated from mass
transfer considerations.  This  suggests that uptake of glutamic acid is
limited by an additional resistance, either in  terms  of mass transfer,
adsorption, or reaction.
LAURIC ACID

High molecular weight  fatty  acids  are very sparingly soluble in water.
The use of alkali  salts  (soaps)  allows forming suspensions at higher
concentrations; however,  these suspensions are unstable.  Plocculation
and settling ,as well as  adsorption on filters  makes it difficult to
work .with such suspensions.   In  order to minimize these problems and
yet work with a reasonably high  molecular  weight fatty acid, lauric acid
was used to study  the  kinetics of fats.  As an  example, lauric acid solu-
tions could be filtered  through  millipore  filters without substantial
loss of fatty acid.  However,  palmitic and stearic acid could not be
handled''in this manner.  :

Biological uptake  of lauric  acid (no other carbon source) was tested
at three concentration' levels,. 25,  50, and 100 mg/1.  All other nutritional
requirements were  available  in excess.  A  slime layer was acclimated to
lauric acid" feed over  a  period of  several  weeks.  Carbon removal was used
as a measure of biological -uptake  because  chemical analyses for fatty acids
are not sufficiently precise to  measure small  differences in concentration.
Each feed*was,tested over a  range  of flow  rates.  The results show that
uptake is essentially  independent  of flow  rate. The rate data are sum-
marized in Figure  35.  Lauric acid shows the same trends as reported for
other substrates,  namely increasing rates  of uptake as feed concentration
is increased.  It  was  not feasible to evaluate higher concentration levels-
due to the low solubility of lauric acid.   However, i| appears that max-
imum uptake rate is in the range 200-250 x 10" mg/cm -min.  The observ-
ed rate data are indicative  of mass transfer limitation in the same manner
observed with glutamic acid  substrate.  The rate of mass transfer calcul-
ated from fche9diffusion  control  model using a  diffusion coefficient of
0.43 x 10~5cm /sec at  20°C is shown In Figure  35, the calculated values
are substantially  higher than the  measured rates of uptake .

-------
                     Figure 35


                Laurie Acid-Carbon Removal
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  280
  240
  200
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   120
          20  40  60  80  100

           FEED  CARBON CONC.  mg/1
                     90

-------
The lauric acid acclijnated slime layer was also tested with a mixed feed
consisting of approximately IQOmg/l each of lauric acid and glutamic
acid and glucose.   The initial rate of organic carbon removal and glucose
disappearance are summarized below.

            Substrate Concentration*    Substrate Removal,-
                   mg/1                 mg/cm -nrin. x 10

Total carbon       139                         238

Glucose           (100)                         48

*Mixed feed, glucose, glutamic acid and lauric acid, nominally lOOmg/1
of each.

Total carbon removal is essentially the same as observed with lauric
acid alone.  However, some glucose removal was observed and accounts for
about 20% of the carbon uptake.
MDED FEED ACCLIMATED SLIME SURFACE

A series of tests were made to determine  the kinetics of substrate re-
moval after slime layers  had been acclimated to mixed substrates.  The
mixed substrate  consisted of 100  mg/1  each of  glutamic acid and lauric
acid and glucose.   Rates  of removals were measured at two levels of feed
concentrations  (nominally 50 and  100 mg/1 each) and over a range of flow
rates.  Peed  and effluent samples were analyzed for carbon, glucose, and
amino acid concentration.

Data from the 100 mg/1 feed mixture show  substantially higher rates of
substrate uptake then had been observed on slime  layers acclimated to
a single substrate.  Data for carbon and  glucose  removal are shown below:

Mixed feed concentration
(glucose, glutamic  acid,                100           50
lauric acid,  mg/1 of each )
                               Substrate Removal,  mg/cm -rain, x 10

Total Carbon                            ^10          160

Glucose                                 760          ^53

Glucose disappearance accounts for the major part of the carbon uptake.
Measurements  of  amino acid removal are inconsistent but the data clearly
point to the  conclusion that rates of  removal  of  glutamic acid are much
smaller than  the rates of glucose removal.
                              91

-------
As a further test of the behavior of mixed substrates, a slime surface
was acclimated to feed solutions containing skim milk solids.  Skim
milk solids are known to consist of high concentrations of lactose (50-5
wt.JO and protein (36.9 wt.J?) plus traces, of fats (0.9 wt.JB) and in-
organics.  Growth of the slime layer was noticeably more rapid than that
observed with single substrates.  Rates of uptake were measured from
carbon and carbohydrate disappearance using four concentration levels and
a range of flow rates.  Protein degradation was not determined quant-
itatively because the analytical techniques were Inadequate.  Average
rates of carbon uptake and carbohydrate degradation are shown in Fig.
36 as a function of substrate concentration in the feed solution.  Car-
bon uptake increased with increasing feed concentrations in the same
manner as observed with single substrates.  It appears that higher
rates of removal could have been obtained by further increasing the
milk solids concentration (range covered was 50-200 mg/1 of dry milk
solids).  Carbohydrate removal accounts for most of the observed carbon
uptake at all concentration levels.  Nevertheless, protein degradation
was noted in all tests.  At low feed concentrations, protein degrada-
tion was nearly complete.
                             92

-------
                Figure  36

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-------
DISCUSSION-^UMARY

Substrate uptake of slime surfaces acclimated to single substrates appear
to be mass transfer limited at concentrations below 100 mg/1, and
reaction limited at higher concentrations.  This conclusion is based on
the observed effects of feed substrate concentration on uptake rate±g
Faximum uptake with single .substrates is in the range 50 - 250 x 10
mg/cm -min.  Highest rates were observed with lauric acid, glucose, and
when mixed substrates were used.  Lowest uptake, rates were-observed with
starch feed; starch-carbon uptake was only 50 x 10   mg/cm -min. even
though the rate of starch degradation was 2-4 fold greater.  By contrast,
protein removal and carbon disappearance are more nearly equivalent.
Both starch and protein molecules are far too large to be absorbed dir-
ectly into bacterial.cells.  Based on an extensive literature review,
Pollock (The:Bacteria, Vol. 4, Academic Press, 1962) has concluded that
exoenzymes, either free or bound to the cell surface, are responsible
for the hydrolytic breakdown of colloids, followed by ingestion of sol-
uble-fragments.  The starch-carbon data'suggest that the sites for hyd-
rolysis and ingestion are independent and physically separated, as
evidenced by the low carbon uptake rate.

Acclimation of the slime surface is necessary when new substrates
are introduced; glucose is an exception.  Acclimated surfaces may loose
their activity for metabolizing a given substrate if the substrate is
removed for any appreciable time.  Some loss in activity may occur in
a few hours as evidenced by the loss of hydrolytic activity for starch
when glucose was substituted for approximately four hours.  Acclimation
of the surface to an entirely new substrate may take several days.

Acclimatization to fatty acids and to glycine are examples.  It is quite
likely that an entirely different surface coating (different bacterial
species) is formed.

Use of mixed substrates generally results in higher rates of carbon up-
take.  This is particularly pronounced when carbohydrates are added.
Preferential utilization of glucose in pure compound mixtures and lac-
tose from skim milk substrates have been observed.  Nevertheless, there
is concurrent utilization of other substrates e.g., protein and starch
degradation as well as some uptake of carbon from noncarbohydrate
sources.

The results of this study provide some new insights on the behavior of
biologically active slime layers in the presence of various' substrates.
The practical 'significance of this work has not been evaluated although
the results do raise some questions about the practical value of certain
operating practices commonly used in trickling filters.  For example,
the use of effluent recirculation would appear to be undesirable if BOD
removal is mass transfer limited.  Also the use of packing which nlnimizea
liquid hold up seems undesirable in a mass transfer limited reactor.
Further work is needed to evaluate the potential value of slime layers in
biological processings and to delineate optimum operating conditions.


                                  94

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                             TABLE NO. 1


Effect of Starch Concentration on Rates of Biological Decomposition

Experiment No. 4-2-68, Batch Reactor, Well Mixed.

Preparation of Innoculum
Collected 1300 ml overflow from continuous propagator (overnight)
using standard soluble starch feed solution  (100 mg/1)

Preparation of Concentrates
0.8 grams of  starch in 399 ml distilled water was autoclaved for 5
minutes to dissolve starch.  Predetermined amounts of concentrate
were added at the beginning of each test.

Sample      Time        Starch Concentration, mg/1  Carbon Concentration
  No                      A=520        X=680               mg/1

Reactor A - 300 ml innoculum + 10 ml  starch  concentrate

A-0         10:00         63           65
A-l         10:10         38           27,5                112.5
A-2         10:20         27           15-5
A-3         10:30         18.5         10
A-4         10:40         15            8.5

   added  30 ml of  starch  concentrate
A-0         11:23         162          179
A-l         11:33         157=5        151
A-2         11:43         144.5        116
A-3         11:53         127           87
A-4         12:03         H2           65
A-5         12:23           88.5         39
A-6         12:43           76           27
A-7           1:03           59-5         21
A-8           1:23           ^8.5         17
A-9           1:56           38           14.5               95

Reactor B -  300  ml innoculum + 20 ml  of starch concentrate

B-0         10:02          126          128.5
B-l         10:12           90           75.5
B-2         10:22           68.5         44
B-3          10:32           56           28
B-4         10:42           46           20
B-5         10:52           35           15-5
B-6         11:02           31           13
                               95

-------
Table No. 1   con't
Sample
No
added
B-0
B-l
B-2
B-3
B-4
B-5
B-6
B-7
B-8
B-9
Reactor
C-0
C-l
C-2
c-3
c-4
C-5
C-6
C-7
added
C-0
C-l
C-2
c-3
C-4
C-5
C-6
C-7
C-8
C-9
Time

25 ml of starch
11:25
11:35
11:45
11:55
12:05
12:25
12:45
1:05
1:25
1:58
Starch Concentration, mg/1 Carbon
X=520
concentrate
182
149
126
109
95.5
75.5
61
-51
43
34
C - 300 ml innoculum + 25 ml
10:04
10:14
10:24
10:34
10:44
10:54
11:04
11:14
20 ml of starch
11:27
11:37
11:47
11:57
12:07
12:27
12:47
1:07
1:27
2:00
153
121.5
99
80
68.5
59.5
51
45
concentrate
170
146
125
109.5
98.5
81
68
58
51
55
A=680 i

171
125
86
61
44
28.5
21
17
15.5
14 !
of starch concentrate
160
107.5 :
71
48
34
26.5
21
17.5

150
114
82
60
46
31
24
18.5
18
16
                                                          mg/i
                                                          97
                                                          124
                                                           94
                             96

-------
Table No. 1   con't
Sarrple       Time        St ^Concentration, mg/1  Carbon Concentrate
  ^u                       A=520       X=680
Reactor D - 300 ml of innoculum + 30 ml of starch concentrate

D-0          10:06         180         183
D-l          10:16         144.5       lofi
D-2          10:26         117          88
D-3          10:36          96,5        57-5
D-4          10:46          83          41
D-5          10:56          69.5        30.5
D-6          11:06          61          24
D-7          11:16          53          18.5

  added 10 ml of concentrate

D-0         .11:29         111          82.5
D-l          11:39          8?          47.5
D-2          11:49          76 '         32.5
D-3          11:59          67          25
D-4          12:09          59          21
D-5          12:29          48.5        17
D-6          12:49          40          14
D-7           1:09          35          13-5;
D-8
D-9                           /                       :    75
Footnotes:   Temperature, 23  centigrade
             Innoculum was filtered  (0.45 micron filter) to determine
               suspended solids and the "dissolved" carbon concentration.
             Innoculum before addition of starch concentrate suspended
               solids, mg/1 35.2, 47.6
               dissolved carbon, mg/1 21.0, 26.0
             Yield of suspended solids in continuous propagator was
               determined from meansurement of dry mass and carbon
               concentration in filtrate and feed.
               cell mass yield 'g      nlmM      0-51,0.795
                             97

-------
                             TABLE NO. 2
Part I - Comparison of Biological Decomposition Rates of Different
        • Starches

         Experiment No. 4-30-68, Batch Reactor, Well Mixed

Preparation of Innoculum
Collected 1250 ml overflow from continuous propagator overnight (18
hours), using standard 100 mg/1 soluble starch feed.  Added 550 ml fresh
feed (100 mg/1) at 10:00 AM and continued aeration.

Preparation of Starch Concentrate
0.8g starch added to 399 ml distilled water and autoclaved for 5 minutes
to dissolve starch.  Concentrate was added to innoculum to bring starch
concentration to 200 mg/1.

Sample No  Time       Starch Concentration, mg/1    Carbon Concentrate
                        X=680       X=520                 mg/1

Reactor A - Evaluation of SD-5 Starch

A-0      Innoculum       4.5         5.0                  16 50
A-l        11:00         198         213                  88'
A-2        11:10         161         155                  82
A-3        11:20         122         130                  71
A-4        11:30          93         108                  63
A-5        11:40          72          97                  50
A-6        11:50          57          87                  10
A-7        12:00          43          76
A-8        12:20          29          59
A-9        12:40          21          45

Reactor B - Evaluation of SD-80 Starch

B-0      Innoculum       4.5         6.0                  16.50
B-l        11:02         192         220                  96
B-2        11:12         155         192                  87
B-3        11:22         128         168                  83
B-4        11:32         114         152                  71
B-5        11:42          99         136                  62
B-6        11:52          92         127               '   23
B-7        12:02          78         113
B-8        12:22          71         100
B-9        12:42          65          80
                             98

-------
Table No. 2  can't.
Sample. No Time       Starch Concentration, mg/1    Carbon Concentrate
                         X=680       x=520        .         rng/1
Reactor C - Evaluation of ES-A
c-o
C-l
C-2
C-3
C-4
C-5
C-6
C-7
C-8
C-9
Reactor
D-0
D-l
D-2
D-3
D-4
D-5
D-6
D-7
D-8
D-9
Innoculuni
11:15
11:15
11:25
11:35
11:45
11:55
12:15
12:25
12:45
D - Evaluation
Innoculum
11:07
11:17
11:27
11:37
11:47
11:57
12:07
12:27
12:47
4.5
194
164
129
93
72
55
41
27
18
of Standard
4.5
183
134
93
64
45
35
27
18
13
5.5
220
167
142
118
103
91
79'
62
47
Soluble Starch
5-0
212
154
126
107
93-5
81
71
54.5
42
                                                          16.50
                                                          85
                                                          86
                                                          70,5
                                                          60
                                                          49.5
                                                          12.5
                                                          16.50
                                                          82
                                                          79-5
                                                          68.5
                                                          52
                                                          41.5
                                                          21
 Footnotes:   Dry weight of biomass measured oh selected samples by
             filtering through 0.45 micron Millipore filters
                                             Biomass, mg/1
                       Innoculum             32»3>  34-5
                       Reactor A             105>8, 104.0
                       Reactor B             104.0
                       Reactor C             94.6
                               99

-------
                             TABLE NO. 3


Part II - Comparison of Biological Decomposition Rates of Different
          Starches

          Experiment No. 5-7J-68

Preparation of innoculum and concentrates same as experiment 4-30-68.

Sample        ,  Time         Starch Concentration, mg/1
  No                           X=680       A=520

Reactor A - Evaulation of PPPS Starch

A-0
A-l
A-2
A-3
A-4
A-5
A-6
A-7

Reactor B -

B-0
B-2
B-3
B-4
B-5
B-6
Reactor C

C-0
C^l
C-2
C-3
C-4
C-5
C-6
C-7
.10.29
10:39
10:49
10:59
11:09
11:19
11:29
11:49
Evaluation
10.31
10:41
10:51
11:01
11:11
11:21
11:31
11:51
Evaluation
10.35
10:45
10:55
11:05
11:15
11:25
11:35
11:55
230
161
112
80
58
44
34
23
of ES-G Starch
175
125
84
60
44
33
26
17
of standard soluble
172
96
56
38
26
20
16
11
220
174
145
126
107
91
75
53

164
129
105
90
79
67
56
39
starch
162
117
95
79
66
55
46
32
                              100

-------
                             TABLE NO.4


                Test for "Soluble" Exor-enzyme Activity

Part I - Experiment No. 2-9-68, Batch  Reactor, Well Mixed

Innoculum collected from continuous propagator using standard soluble
starch feed solution of 100 mg/1.  Fresh feed solution was added at
the beginning of the test.  Part of innoculum was filtered through
0.45 micron Millipore filter to remove cell mass.

Sample No       Time          Starch Concentration, mg/1
                                X=520       X=680

Reactor A - 100 ml innoculum + 200 ml  feed solution

A-l             2:40             61.5       62.5
A-2             2:55             36.0       28.5
A-3             3:10             23.0       13.0
A-4             3:25             10.5        7.0

Reactor B - 50 ml millipore filtered innoculum + 100 ml feed solution

B-l             2:43             66.0       64,0
B-2             2:58             66.0       63..0
B-3             3:13             65.0       62.5
B-4             3:28             64.5       61.5
B-5             3:50             64.0       59.5
B-6             4:40             63-5       58.5
Footnotes:   Temperature, 20 C.                             „,,«*,«„
             Innoculum starch concentration, non detectable • carbon
              concentration, 25 mg/1
                              101

-------
                             TABLE NO,5
Part II - Experiment No, 2-10-68, Batch Reactor, Well Mixed

(InnQculum collection and test procedure same as Part I test
No, 2-9-68)
Sample
No
Reactor
E-l
E-2
E-3
E-4
E-5
E-6
E-7
E-8
E-9
E-10
E-ll
E-12
E-13
Reactor
P-l
F-2
P*3
F-4
P-6
Time

Starch Concentration mg/1 Carbon Concent
X-520
E - 100 mg innoculujn + 300 ml
9:43
9:58
10:13
10:28
10:43
10:58
11:13
11:28
11:43
11:58
12:28
12:58
1:28
P - 50 ml
9:00
10:05
10:20
10:35
11:05
80.0
57.0
42.0
31.5
24.5
19-0
15.5
13,5
11.5
8.5
4.0
2.0
2.0
millipore filtered
80
80
80
80
79
X=680
feed solution

49-5
31.5
20.0
14.0
10.0
8.0
7.0
6.0
5.0
3-5
2.0
2.5
innoculum + 150 ml
73
74
74
74
74
mg/i

38.5
37.0
35.0
34.0
33-0



32.0
30.0

31.5

fresh feed





Footnotes:  Temperatures 20  centigrade
                              102

-------
Table No.5   con't
Sample
  No
            Tame
          Starch Concentration rng/1
            X=520       X=680
Reactor G - 100 ml  Innoculum +  300 ml  fresh feed
G-l
G-2
G-3
G-4
G-5
G-6
G-7
G-8
G-9
G-10
G-ll
            1:
            1:
            1:
            1;
            2:
            2:
            2:
            3:
            3:
            4:
10
25
40
55
19
35
50
05
35
05
             4:55
79.0
61.0
52.0
46.0
40.0
35,
34,
32.0
27 = 5
22.0
14.5
,5
-5
75.0
57-5
44.0
35.0.
26.5
20.0
18.5
17.0
12.0
10.0
 6.0
Reactor  H -  50 ml filtered innoculum + 150 ml  fresh feed
H-l
H-3
H-5
H-6
H-7
H-8
H-9
H-10
               44
               21
               55
             3:10
             3:50
             4:15
             5:00
                        75.5
                        76.0
                        74,
                        75,
             after 17 hours
                        74.0
                        73-5
                        68.0
                        56.5
 Footnotes:   Temperature 21  centigrade
             Innoculum starch concentration, 3 mg/1
                              103

-------
                             TABLE NO. 6
Biological Decomposition of Starch-Glucose Mixtures

Experiment No. 8-29-68, Batch Reactor, Well Mixed

Preparation of Innoculum
Collected 1500 ml of overflow from continuous propagator using standard
100 mg/1 soluble starch feed solution.  Innoculum was collected over-
night in an aerated vessel and diluted with salt solution-of equal
volume.  Each reactor was started with 600 ml of inncoeulum.

Preparation of Concentrate
One gram of starch and glucose were dissolved in 500 ml and 250 ml
respectively of distilled water and autoclaved for 5 minutes.  :Concentrates
were added to each of four reactors as shown.
Reactor
A
B
C
D
                           Concentrate  added, ml
                        Starch         Glucose
                        30
                        30
                        60
                        0
                            0
                            15
                            15
                            15
Sample No.
Reactor A

A-0
A-l
A-2
A-3
A-4
A-5
A-6
A-7
A-8
A-9
A-10
A-ll
A-12
A-13
A-16
A-17
A-18
A-19
Time
10:36
10:40
10:55
11:10
11:25
11:40
11:55
12:10
12:25
12:40
 1:11
' 1:40
 2:
 2:
 5:
 5:
 6:
4o
40
30
50
Starch Concentration, mg/1

X=680          X=520
2.0
9.8
82.5
62
54
48
43
39-
36.
30.
25,
21.

 7-5
 1.5
                      2.5
                      104
                      92
                      82
                      76
                      71
                      67
                      65
                      62
                      72
                      53
                      46
                      38
                                          Carbon

                                          mg/1
                                              Glucose

                                              mg/1
 7:56
                                  53 (11:03)



                                  591(12:05)

                                  49 (12:58)
                                  33 ( 3.04)
                                  28 ( 3-58)
                                  25
                                  25
                                  25
5

1

1



1

1

3
                               104

-------
Table No.  6 con't
Sample No.      Time       Starch Concentration, mg/1        Carbon       Glucose

                                                             mg/1         mg/1

Reactor B

B-0             10:37      2.5             3-                              0
B-l             10:42      94.5            99                 -            103
B-2             10:57      79,5            85                              122
B-3             11:12      66.5            77                 86  (11:11)   101.5
B-4             11:27      56.5            71                              102
B-5             11:^2      49.             66                              98
B-6             11:57      43.5            63                              108
B-7             12:12      39.5            61                              97
B-8             12:27      35              57                              81
B-9             12:42      31.5            55                              92
B-10             1:12      27                                86  (1:08)    88.5
B-ll             1:42      23              45                              78
B-12             2:12      19,5            35                              66
B-13             2:42                                        67  (2:30)    53
B-14             3:22                                        57  (3:10)    28.5
B-15             3:51                                        41  (4:09)    14.5
B-17             6:48      18                                32  (5:30)    15-
B-18                                                         25  (6:50)
B-19                                                         24  (7:56)

Reactor C

C-0             10:38      2.5
             56                53
                               49


105
                            3.5
 r iR              7-ns>      "R1  ^            56
 C-18              7.02      31.5                              49 (8;05)
                                                             113
 C-3              11: 16      149            l8l                            97
 C-4              11:31      138-5          175                            97
 C-5              11:47      126            l6l                            94
 C-8            : 12:31      100            137                               .

 ^            %$      M             li                S7  (!:»)     3.5

                                                              73(2:»2)       5
 C-13              2=53      52-5            9                    ,
 C-ii)              3:23      48              88                90

                  ?•§      S3'5             °                68(^:2^     18-
                                                                 (600)     25

-------
Table No. 6 can't
Sample No.      Time       Starch Concentrate, mg/1          Carbon       Glucose

                           A=680          A=520              rag/1         mg/1

Reactor D

D-0             10:39      24                               0
D-l             10:48      2              3                               109
D-2             11:03      2              3                               109
D~3             11:18                                        57 (11:22)   109.5
D-4             11:33                                                     105
D-5             11:48                                -                     105
D-6             12:03                                '                     103
D-7             12:18                                        55           99
D-8             12:33                                                     97
D-9              1:18                                        47 (1:30)    87
D-ll             1:48                                                     76
D-12             2:18                                                     68
D-13             2:56                                        40           58
D-14             3:22                                        34 (3:28)    49
D-15             3:56                                                     36
D-17             4:25                                        25 (4:40)    4
D-18             7:02                                        16 (6:00)    11
D-19                                                         14 (7:18)
D-20                                                         11 (8:05)

Reactors                                          A           B  C

Innoculum Composition. Before Test
    blonass .(milipore filtered), mg/1             11         9   10
    carbon content of filtrate, mg/1              12         13  ll

After Test
    blomass, mg/1                                 36         66  94.
    carbon content of filtrate, mg/1              11.5       16   4
                             106

-------
                             TABI£ NO.  7


Effect of Glutamic Acid Concentration on Rate of Biological Decomposition

Experiment No. 12-20-68, Batch Reactor, Well Mixed.

Innoculum Preparation
Collected overflow from continuous propagator  (110 ml/19 hours) at an
average of 58 ml/hr  using  100  mg/1 glutamic acid feed  solution.  Prior
to the test  the  Innoculum  was  diluted with an equal  volume of fresh
feed solution.

Preparation  of Concentrate
0.25 grams of glutamic acid was dissolved  in 1000 ml of distilled
water and sterilized for 5 minutes.

Sample No         Time                 Concentration,  mg/1
                                     Carbon        Amine Nitrogen

Reactor A -  200  ml  of innoculum
A-0                11:30                26                 .62
A-2                12:00         •       26                 54
A-3                12:30                                  60
A-4                 1:00                27                 60
A-5                 1:30                                  53
A-6                 2:00                25                 52
A-7                 2:30                                  51
A-8                 3:00                25                 58
A-9                 3:30                                  52
A-10               4:00                22                 54
A-ll               6:00                21                 30
A-12               7:00               20                 32
A-13              10:00 A.M.          10                 35

Reactor B -                                               ,
 B-0                11=32               26                 24
       added 40 ml concentrate                               .,
 B-l                11:33               37                33
 B-2                12:02               37                18
 B-3               12:32                                 26
 B-ll                 1:02               36                2f
 E-5                 1:32                                 32
 B-6                2:02                34
 B-7                2:32                                  g
 B-8                3:02                32                 26
 B-9                3:32                                   7
 B-10               4:02                30                 37
 B-ll               6:01                25                 3b
 B-12               7:01                27                 &
 ill3              10:02 A.M.           14                 37
                               107

-------
Table No.7   con't
Sample No         Time
   Concentration, mg/1
Carbon         Amine Nitrogen
Reactor C -
C-0
added 80 ml
C-l
C-2
C-3
C-4
C-5
C-6
C-7
C-8
C-9
C-10
C-ll
C-12
C-13
Reactor D -
D-0
added 120 ml
D-l
D-2
D-3
D-4
D-5
D-6
D-7
D-8
D-9
D-10
D-ll
D-12
D-13

11:34
concentrate
11:34
12:04
12:34
1:04
1:34
2:04
2:34
3:04
3:34
4:04
6:02
7:02
10:04 A.M.

11:36
concentrate
11:37
12:06
12:36
1:06
1:36
2:06
2:36
3:06
3:36
4:06
6:03
7:03
10:06 A.M.
                                      26

                                      47
                                      47

                                      48

                                      47

                                      46

                                      41
                                      36
                                      36
                                      15


                                      26

                                      53
                                      55

                                      54

                                      53

                                      52

                                      50
                                      43
                                      36
                                      16
                    112

                    114

                    112
                    110
                    110
                    108
                    108
                     53
                     40
                     50
                     38


                     33

                     43
                     45
                     40
                     42
                     47
                     44
                     46
                     45
                     45
                     46
                     40
                     43
                     43
Footnotes:  Suspended solids concentrations were exceedingly low,  1-2
mg/1 which is difficult to measure precisely.
                              108

-------
                             TABLE NO. 8
Effect of Glutamic Acid Concentration on Rate of Biological Deconposition

Experiment No. 2-5-69, Batch Reactor, Well Mixed

Preparation of Innoculum
Collected overflow from 250 ml continuous propagator (overnight) using
100 mg/1 glutamic acid feed at flow rate of 110 ml/hr.   Each reactor was
started with 245 ml of innoculum.

Preparation of Concentrate
0.200 grams of gultamic acid and  200 ml of distilled water were sterilized
for 5 minutes.  Concentrate lost  some water by evaporation, final
concentration was 1.03 mg/ml.  Concentrate was added to each of four
batch reactors at the beginning of  the test.
Sample No   Time
Reactor B

B-l

B-2
B-3
B-4
B-5
B-6
B-7
B-8
B-9
B-10
B-ll
B-12
B-13
B-14
B-15

Reactor C

C-l

C-2
C-3
C-4
C-5
C-6
  : 31
10:
10;
10:31
11:01
11:31
12:01
12:31
 1:01
 2:00
 3:01
 4:01
 5
 5
 8
 9
 9:30
10
10
10
11
11
12
   49
   15
   40
:20
:33
:33
:02
:32
;02
              Concentration, mg/1  •
           Carbon        Amine Nitrogen
          6.0              2.0
     added 25 ml concentrate
         49-0              8.4
         38.0              9.3
         28.0              8.0
         22.0              3.4
         13.0              2.2
          8.0              1.8
          8.0              1.6
12:32
             9-0
             8.0
             8.0
             6.0
       added 40 ml
            71.0
            67.0
            57-0
            51.0
            43.0
                           1.6
                           0.8
                           1.6
                           1.5
                           1.8
                           1.9
           2.0
concentrate
          13-2
          13-7
          12.7
           8.5
           7-4
                               109

-------
Table No. 8  can't

Sample No   Time
Reactor C con't
C-7
C-8
C-9
C-10
C-ll
C-12
C-13
C-14
C-15

Reactor D

D-l

D-2
D-3
D-4
D-5
D-6
D-7
D-8
D-9
D-10
D-ll
D-12
D-13
D-14
D-15
           1:
           2:
           3:
           4:
02
00
02
02
           5:13
           5:52
           8:15
           9:40
           9:30
:23
:36
:36
:03
:33
:03
:33
:03
:00
:03
:03
:16
:55
:15
10:
10:
10:
11:
11:
12:
12:
 1:
 2:
 3:
 4:
 5:
 5:
 8:
 9:40
 9:30
                        Concentration, mg/1
                     Carbon        Amine Nitrogen
24.0
 9.0
 9-0
10.0
 7.0
11.0
         11.0
                           4-7
                           2.4
                           1.0
                           1.0
                           1.1
                           1.2
                           1.7
                           2.2
                           2.7
                       6.0              2.1
                  added 50 ml concentrate
                      85.0
                      80.0
                      71.0
                      61.0
                      52.0
                      34.0
                      12.0
                      13.0
                      14.0
                      13.0
                      13-0
                      16.0
                      16.0
                      16.0
                            .4
                            .3
                            .7
                 16.
                 17.
                 15-
                 11.0
                 11.1
                  6.7
                  0.3
                           1,
                           0.
                           1.
                           1,
                           2.1
                           2.6
                           3.1
Footnotes:  a)  The quantity of suspended material (cell mass) was
                determined by filtering through 0.45 micron filters and
                drying and weighing.
  Sample filtered      Solids collected     Concentration of filtrate
                            mg/1         Carbon, mg/1 Amine Nitrogen mg/1
                            30.0             10.0            0.6
                            51.0              9-0
                            82.5             12.0
                            79.0             16.0
Innoculum
Reactor B, end of test
Reactor C, end of test
Reactor D, end of test
                                              1
       —  j 	      - - -     •--               	-Q
b)Temperature was maintained at approximately 21  centigrade
                                       8
                                     2.2
                                     1.3
                              110

-------
                             TABLE NO.  9
Glycine Degradation by Glutamic Acid Acclimated Innoculum

Experiment No. 2-20-69. Batch Reactor, Well Mixed.

Innoculum Preparation
Collected overflow from continuous propagator, 2,200 ml in 15 hours,
using 100 rng/1 glutamic acid feed.

Preparation of Concentrate
0.404 grams of glycine was  dissolved in  200 ml distilled water and
sterilized for 5 minutes.   Concentrate was added to innoculum at the
start of each test.
Sample No
Time
                  Concentration,  mg/1
               Carbon          Glycine
Reactor A
A-l

A-2
A-3
A-4
A-5
A-6
A-7
A-8
A-9
A-10
A-12
11:
11:
11:
12:
12:
 1:
 1:
 2:
 3:
 3:
 5:
11:
35
40
40
10
40
10
38
10
11
55
10
44
              7                  7-5
added 5.0 ml concentrate to 250 ml of  innoculum
             18.
             23.5
             23
             20.5
             27
             25
             23-5
             20
             23
             19
                                     47
                                     50
                                     52
                                     52
                                     50
                                     48
                                     37
                                     32.
                                     20
                                     21
 Reactor B
 B-l

 B-2
 B-3
 B-4
 B-5
 B-6
 B-7
 B-8
 B-9
 B-10
 B-12
11:35
11:41
11:41
12:10
12:41
    38
                  7                  7.5
    added 15 ml concentrate to 250 ml innoculum
                 143                112
                 149                118
1
1
2:10
3:12
3:55
5:11
11:44
                 49-
                 47.
                 .46
                 48
                 56
                 51.
                 49
                 40
                               125
                               125
                               125
                               126
                               125
                               127
                               122
                                96
                               111

-------
Table No.  9 con't
Sample No
Reactor C
C-l

C-2
C-3
C-4
C-5
C-6
C-7
C-8
C-9
C-10
C-12

Reactor D
D-l

D-2
D-3
D-4
D-5
D-6
D-7
Time
D-9
D-10
D-12
11:
11:
11:
12:
12:
 1:
 1:
 2:
 3:
 3:
 5:
11:
35
42
42
11
42
12
39
11
12
56
11
44
11:
11:
11:
12:
12:
 1:
 1:
 2:
 3:
 3 =
 5:
11:
37
43
^3
12
43
12
39
11
13
56
12
44
                  Concent rat ion 3 mg/1
               Carbon           Glycine
              7                  9.5
added 25 ml concentrate to 250 ml. innoculum
             66                165
             79
             75
             74
             75
             83
            100
             83
            100
,5
,5
.5
.5
187
187
187
187
187

187
245
176
              5                  7.5
added 35 ml concentrate to 250 ml innoculum
             93
             98
             99
             97
            100
          95-100+
             74
            102
             82
            102
               235
               235
               235
               235
               235
               235
               187
               245
               187
               245
Footnotes:  Suspended solids measured by millipore filtration
            Innoculum        2.03 8.2, mg/1
            Reactor A        20.0 mg/1
            Reactor c        33-7 mg/1
                               112

-------
                             TABLE NO.  10


Protein and. Glutamic Acid Degradation on Glutamate Acclimated Innoculum

Experiment No. 3-12-69, Batch Reactor, Well Mixed.

Innoculum Preparation
Collected overflow  from continuous propagator overnight (150 ml/hr)
using 100 mg/1 glutamic acid feed solution.  Microscopic examination
showed predominance of rod  shaped bacteria  (length to width ratio of
3-4).  Mostly single cells  except for a few small clumps.

Preparation of Concentrates
0.200 grams glutamic acid + 200  ml distilled water.
0.200 grams peptone +  200 ml distilled  water.
Concentrates were autoclaved for 5 minutes.

Sample No         Time                 Concentration, mg/1
                                  Carbon   Amino Acid   Protein

Reactor  A  -
A-0               10:56              10        24           0
      added 30 ml protein concentrate +  245 ml innoculum
A-l               10:59              54        51         115
A-2               11:30              55        52         125
A-3               12:01              52        45         125
A-4               12:37              52        10         110
A-5                1:39              48        28         115
A-6                2:43       •.      48        25         110
A-7                3:55             45        25         HO
A-8                4:58             45        33
A-9                6:23             ^5        25
A-10               9:10             52        27
A-ll              10:25             44        25
 A-12               9:07             45       43

 Reactor B -                                    ft            n
 B-0               11:01             10       18            0
       added 60 ml protein  concentrate + 245 ml  innoculum
 R_l               11:03             90        92          
-------
Table No. 10 can't
Sample No         Time                 Concentration, mg/1
                                  Carbon   Amino Acid   Protein
Reactor C -
C-0
added 90
C-l
C-2
C-3
C-4
C-5
C-6
C-7
C-8
C-9
C-10
C-ll
C-12
Reactor D -
D-0
added 60

11:05
ml protein
11:07
11:33
12:05
12:39
1:41
2:45
2:57
5:00
6:24
9:11
10:26
9:09

11:08
ml protein

10
concentrate +
118
120
123
116
116
109
105
105
105
100
99
89

10
concentrate +

34

0
245 ml innoculum
137
129
152-170
17
43
60
60
75
72
75
55
75

29
15 ml glutamate
295
290
310
255
275
250
230







concentrate
+ 245 ml innoculum
D-l
D-2
D-3
D-4
D-5
D-6
D-7
D-8
D-9
D-10
D-ll
D-12
Reactor E
E-0
added 60
+245 ml
E-l
E-2
E-3
E-4
E-5
E-6
E-7
Er8
E-9
E-10
E-ll
E-12
11:11
11:34
12:06
12:40
1:42
2:48
3:58
5:01
6:24
9:11
10:26
8:09

11:12
ml protein
innoculum
11:15
11:34
12:06
12:43
1:43
2:47
3:59
5:02
6:25
9:12
10:26
9:11
108
105
108
100
94
86
80
81
77
74
74
60

12
concentrate +

115
105
108
118
110
105
91
82
80
80
80
76
160
157
174
25
50
43
86
99
90
67
49
94

15
30 ml gltamate


157
174
25
118
105
121

129
105
75
. 89
200
220
210
190
195
185
180







concentrate

200
220
210
210
185
180
185





                             114

-------
Table No.  10 can't


Sanple No         Time                 Concentration, mg/1
                                   Carbon   Amino Acid   Protein

Reactor F  -
F-0               11:16             11        26
      added 60 ml each of protein  and glutamate concentrate + 245 ml
      inncoulum
F-l               11:19            144       224         175
F-2               11:37            148       24?         190
F-3               12:08            156       236         195
F-4               12:43            156        26         165
F-5                 1:44            140       163         175
F-6                 2:47            132       115         180
F-7                 4:00            124       192         175
P-8                 5 = 03            111       217
F-9                 6:25             88       207
F-10                9:12             78       181
F-ll              10:28             76       149
F-12                9:11             70       115

Reactor G  -  (No  concentrate  added)
G-0  (22°c)       11:17              6        25
G-2  (23°c)       11:38             11
G-3  (24°c)       12:11             11        25
G-4   "           12:45             16
G-5   "             1:47             14
G-6   "             2:47             12
G-8                 5:04             20
G-9   "             6:26             19
G-10  "             9:13             16
Footnotes:   Temperature of reactors  is indicated by numbers in paren-
              thesis in Reactor G  data columns
             Suspended solids measured by millipore filtration and drying
              and weighing
              Innoculum                    26.5 mg/1
             Reactor D
                               115

-------
                             TABLE NO. 11
Effect of Concentration on Biological Degradation of Peptone and
Glutamlc Acid using a Peptone Acclimated Culture

Experiment No. 3-18-69, Batch Reactor, Well Mixed.

Preparation of Innoculum
Collected effluent from continuous propagator overnight using 100
rng/1 Bacto-Peptone feed at a flow rate of 150 ml/hr.  Each reactor was
started with 245 ml of innoculum.

Preparation of Concentrates
a)  Dissolved 0.400 grams of Bacto-Peptone in 400 ml distilled water
b)  Dissolved 0.200 grams of glutamic acid in 200 ml. distilled water
Both concentrates were autoclaved for 5 minutes
Sample No
Time
Reactor A
A-0
added
A-l
A-2
A-3
A-4
A-5
A-6
A-7
A-8
A-9
A-10
A-ll
Reactor B -
B-0 '
added
B-l
B-2
B-3
B-4
B-5
B-6
B-7
B-8
B-9
B-10
B-ll

10:07
30 ml of peptone
10:32
11:01
11:29
11:59
12:59
1:58
2:55
3:58
4:56
8:18
10:25

10:07
60 ml of peptone
10:33
11:02
11:29
11:59
12:59
1:39
2:55
3:55
4:57
8:18
10:28

11
concentrate
51
50
48
48
40
28
24
16
23
16
15

11
concentrate
83
82
81
78
70
57
49
41
38
26
15
     Concentration, mg/1
Carbon  Amine Nitrogen
                                              17.8

                                              16.5
                                              17 = 5
                                              17 = 5
                                              18.0
                                              13.9
                                              16.4
                                              14.8
                                              14.8
                                              16.2
                                              17.6
                                              17.5
                                              15-1

                                              17.5
                                              16.9
                                              16
                                              17.2
                                              17.8
                                              17.8
                                              15-2
                                              14.0
                                              16.8
                                              15.5
                                              17 = 5
                                                           Peptone
                                           30

                                          120
                                          120
                                          120
                                          110
                                          100
                                           90
                                           60
                                           45
                                           35
                                           25
                                           20
                                           25

                                          195
                                          190
                                          185
                                          150
                                          170
                                          140
                                          110
                                           90
                                           70
                                           40
                                           20
                            116

-------
Table No.  11 con't
Sample No         Time                 Concentration, mg/1
                                 Carbon   Amine Nitrogen   Peptone
Reactor C -
C-0
added 90 ml
C-l
C-2
C-3
C-4
C-5
C-6
C-7
C-8
C-9
C-10
C-ll
Reactor D -
D-0
added 60 ml
D-l
I>-2
I>3
D-4
D-5
I>6
D-7
D-8
D-9
D-10
D-ll
Reactor E -
E-0
added 60 ml
E-l
E-2
E-3
*»rf ^
E-4
E-5
E-6
E-7
L-^ f
E-8
E-9
E-10
E-ll

10:08
of peptone
10:35
11:02
11:30
11:59
12:59
1:59
2:55
3:58
4:57
8:18
10:28

10:10
of peptone
10:37
11:09
11:35
12:03
1:06
2:02
3:01
4:13
5:09
8:22
10:33

10:10
of peptone
10-: 38
11:09
11:36
12:03
1:06
2:03
3:02
4:14
5:09
8:30
10:40 ,

11
concentrate
115
115
110
106
102
89
74
62
60
37
32

9
concentrate
100
100
92
92
83
68
57
46
32
30
22

9
concentrate
115
115
106
104
96
79
65
53
40
28
13

15.3

16.2
14.8
13.6
14.1
19.7
15.0
16.2
15-1
12.8
13-6
14.3

17.8
+ 15 ml glutamate
20.2
18.7
24.0
27.0
22.8
23-9
20.4
18.3
18.0
13.9
14.5

14.7
+ 30 ml glutamate
21.7
25.1
23.9
27-7
26.0
27-0
22.3
18.6
17.6
18.8
19-3

25
*«••> ^
260
265
245
245
240
205
180
185
125
55
40

25
concentrate
185
200
175
170
155
140
115
185
85
45
25

25
concentrate
17.5
175
165
165
150
135
110
95
75
40
35
                               117

-------
 Table  No.  11 con't
 Sample  No         Tame                Concentration, mg/1
                                Carbon   Amine Nitrogen    Peptone

 Reactor P  -         l                '
 F-0               10:10            9          19.5            25
      added 60 ml each of peptone and glutamate concentrate
 F-l               10:39          129          30.3           165  * '
 F-2               11:04      '    124          34.4           160 .
 F-3               11:36          127          33.0           150
 F-4               12:03          125          37-5           150
 F-5                 1:06          117          30.6           140
 F-6                 2:03          104          28.3           130
 F-7                 3:02           88          21.0           115
 F-8                 4:14           76          21.2           100
 F-9                 5:10           65          20.6            85
 F-10               8:35           35          18.7            50
 F-ll             10:45           31          13-7            40
Footnotes:  Temperature - 25°
            Innoculum suspended solids concentration, 22.7, 35.2 mg/1
                              118

-------
                             TABLE NO.  12
Biological Degradation of Glutamate, glycine and Peptone using
Glutamate Acclimated Innoculum.

Experiment No.  3-20-69,  Batch Reactor, Well Mixed.

Preparation of  Innoculum
Collected effluent  overnight  from continuous propagator using 100 mg/1
glutamic acid feed  solution at  approximately 130 ml/hr.  Each batch
test was started with 245 ml  of innoculum.

Concentrate Preparation
a)  0.400 grams peptone  + 400 ml distilled water
b)  0.200 grams glycine  + 200 ml distilled water
c)  0.200 grains glutamic acid + 200 ml distilled water
Each concentrate was autoclaved for 5 minutes

Sample No         Time               Concentration, mg/1
                                  Carbon      Amine Nitrogen

Reactor A -
A-0               11:00               7            1-9
       added  30  ml glutamic  acid concentrate
A-l               11:07              ^9           12-5
A-2               11:40              46           12.5
A-3               12:11              41           11.0
A-4               12:46              31          .  6.5
A-5                1:48              20            6.0
A-6                2:47              15            3.4
A-7                3:45              11            2.0
A-8                4:55             13            2.5
A-9                7:37             12            2.0
A-10               9:05             13            2.0
A-ll              11:07             11            2.5

Reactor B -                                         ,
B-0               11:10              ?            0.6
       added 15 ml each of glycine and glutamic acid concentrate
B-l               11:08             45            7.0
B_2               11:40             43           6.6
B-3               12:11             37            6.0
 B-4               12:46             32           6.2
                    1:49             28           6.0
                    **             3            2-0
               -       o              i             "
                               119

-------
Table No. 12 con't

Sample No         Time
Reactor C. -
C-0
      added
C-l
C-2
C-3
C-4
C-5
C-6
C-7
C-8
C-9
C-10
C-ll
D-ll
   Concentration, mg/1
Carbon      Amine Nitrogen
Reactor D -
D-0
added
D-l
D-2
D-3
D-4
D-5
D-6
D-7
D-8
D-9
D-10

11:00
30 ml
11:15
11:43
12:15
12:48
1:54
2:50
3:50
5:00
7:40
8:08
Reactor E -
E-0
added
E-l
E-2
E-3
E-4
E-5'
E~6
E-7
E-8
E-9
E-10

11:00
30 ml
11:16
11:44
12:15
12:48
1:55
2:51
3:50
5:00
7:41
9:08
E-ll
11:00
30 ml
11:10
11:41
12:12
12:46
1:49
2:4?
3 = 45
4:55
7:38
9:05
11:07
11:00
30 ml
11:15
11:43
12:15
12:48
1:54
2:50
3:50
5:00
7:40
8:08
11:10
11:00
30 ml
11:16
11:44
12:15
12:48
1:55
2:51
3:50
5:00
7:41
9:08
7:30
7
0.6
glycine concentrate
41
43
47
44
50
43
42
44
43
40
38
7
glutamate and 30
72
72
69
66
45
38
32
29
23
22
21
7
each of glycine,
102
99
95
91
74
70
61
58
49
49
46
9.6
9.5

9.5
11.6
9.3
10.0
9.1
8.9
8.3
8.7
0.6
ml glycine
9.4
9.5
9-3
10.5
8.0
7.2
5.5
3.3
2.0
2.5
1.7
0.4
glutamate and peptone
9.3
7.3
7.5
9.0
8.0
6.5
6.0
4.7
2.5
2.8
2.0
                             120

-------
Table No .  12 can't
Sample No
Reactor F
F-l
F-2
F-3
F-4
F-5
F-6
F-?
F-8
F-9
F-10
F-ll
       added
                  Time
                   11:00
   Concentration,  mg/1
Carbon      Amine  Nitrogen
                                    12
                 0.4
                   30 ml each of glycine and glutamate and 90 ml peptone
                  11:18
                  11:44
                  12:16
                  12:48
                    1:55
                    2:51
                    3:51
                    5:00
                    7:42
                    9:08
                   11:10
  156
  156
  156
  152
  143
  132
  121
  106
   97
   98
   93
 9.5
 8.7
 9.7
 8.7
10.4
 5.0
 8.8
 6.3
 4.7
 3.0
 2.5
 Footnotes:   Imoculiin suspended  solids concentration, 23-6, 23.2 mg/1
          •>    Suspended solids  at  end of batch test
               Reactor B            12.5 mg/1
          /;    Reactor C            14.2 ng/1
          r    Reactor &            &%**%
          '     Reactor E            J3.0 mg/1
             .  Reactor F            I1-
                                121

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                             TABLE NO. 13


Determination of Carbon Residues from Glutamic Acid Metabolism

Experiment No 6-19-69, Batch Reactor, Well Mixed

Preparation of Innoculum
Collected effluent from continuous propagator overnight (125 ml/hr).
Propagator feed solution contained 100 mg/1 glutamic acid.  About one
half of the innoculum material was filtered through a 0.45 micron
Millipore filter.

Concentrate Preparation
0.400 grams of glutamic acid was dissolved in 400 ml of distilled
water and autoclaved for 5 minutes.

Sample No         Time                    Concentrate, mg/1
                                       Carbon       Glutamic Acid

Reactor A - 200 ml of innoculum, no concentrate added
A-l               11:35                  4               13
A-3               12:53                  9               13
A-4                2:26                  4                8
A-5                4:40                  7                7
A-6                7:35                  5                7
A-7               11:17                  6                8
A-8                8:07                  8               10

Reactor B - 200 ml of innoculum + 20 ml of concentrate
B-l               11:35                  4               11
B-2               11:47  added concentrate              104
B-3               12:53                 38              100
B-4                2:26                  8               25
B-5                4:40                  7               13
B-6                7:35                  5               10
B-7               11:17                  7                8
B-8                8:20                  5               10

Reactor C - 200 ml of innoculum + 40 ml concentrate
C-l               11:35                  5                4
                  11:48  added concentrate
C-2               11:52                 68              158
C-3               12:54                 73              200
C-4                2:27                 43              116
C-5                4:40                 12               38
C-6                7:30                  8               30
C-7               11:17                 10               25
C-8                8:10                 12                8
                               122

-------
Table No.  13 con't
Sample No         Tame                   Concentrate, mg/1
                                      Carbon       Glutamlc  Acid

Reactor D - 50 ml each of raw innoculum and filtered innoculum
D-l               11:35                  4                3
D-3               12:55                  4                5
D-4
D-5
D-6
D-8

Reactor E
E-l

E-2
E-3
E-4
E-5
E-6
E-7
E-8

Reactor F

P-l

F-2
F-3
F-4
F-5
F-6
F-7
F-8
3:00
4:40
7:28
11:17
8:12
2
4
3
5
4
50 ml each of raw and filtered innoculum +
11:40
11:50 added
11:54
12:59
2:31
4:45
7:26
11:17
8:14
3
concentrate
40
33
20
6
5
5
5
2
1
2
15
5
10 ml of concentrate
4

67
108
60
13
a5
4
3
20 ml raw innoculum + 80 ml filtered innoculum + 10 ml
of concentrate
11:40
11:52 added
11:56
1:00
2:36
4:45
7:25
11:17
ft-1R

2
concentrate
39
36
33
16
5
5 '
4

8

78
108
90
43
15
7
3
                               123

-------
Table No. 13 con't
Sample No         Time                   Concentrate, mg/1
                                      Carbon '   '   Glutamic Acid

G    29 ml raw innoculum + 80 ml filtered^innoculum
G-l               11:40                  '3
G-3                1:00                 14
G-4                2:32                  2                2
G-5                4:45                  4                1
G-6                7:24                  3                2
G-7               11:17                  3                2
G-8                8:17                  2                0
Footnotes:  All reactors were filtered at the end of the experiment
     Reactor                          Concentrate, mg/1
                                 carbon            suspended solids
       A                           6                    21
       B                           7                    37-4
       C                          11                    40
       D                           68
       E                           6                    24
       F                           6                    26
       G                           4                   N.D.
                             124

-------
                             TABLE NO. 14

Effect of Milk Solids Concentration on Rate of Deconposition

Experiment No. 8-12-69, Batch Reactor, Well Mixed

Preparation of Innoculum
Continuous propagator was  operated on 100 mg/1 milk solids feed
solution at 148 ml/hr.  Innoculum was collected overnight.

Concentrate Preparation
0.400 grams of milk solids were dissolved in  400 ml distilled water
and  autoclaved.

Batch Tests
Four batch tests  were  set  up using different  amounts of concentrate.
Samples were  withdrawn periodically  and  analyzed for total carbon,
carbohydrate, and protein.  Effluent was collected overnight.
Batch Reactor           Innoculum              Concentrate
      A
      B
      C
      D

 Sample No
 A-l
 B-l
 C-l
 D-l
 A-2
 B-2
 C-2
 D-2
 A-3
 B-3
 C-3
 D-3
 A-4
 B-4
 C-4
 D-4
 A-5
 B-5
 C-5
 D-5
 A-6
 B-6
 C-6
 D-6
Time
 9:20
 9:20
 9:20
 9:20
 9:
 9:
 9:
10
10
10
10
11
11
11
11
12
12
12
12
 1
 1
 1
27
29
30
.30
31
32
:33
:25
:25
;24
:26
:28
:29
:25
:29
:34
:37
:33
       >300 ml
        300 ml
        300 ml
        300 ml

          At
        Minutes
 1:33
  7
  9
 10
 70
 71
 72
 73
125
125
124
126
188
189
185
189
254
257
253
253
                        0 ml
                       30 ml
                       60 ml
                      -100 ml

                Concentrate, mg/1
          Carbon   Carbohydrate
14
12
13
13

33
49
73
13
40
61
77
12
38
59
75
16
33
55
71
13
29
52
62
                                 6
                                 5
                                 5
46
65
78
 7
48
65
78
 1
43
63
88
 8
41
62
77
 5
41
63
75
Protein

  13
   8
   5
   8

  18  -
  30
  65
  10
  45
  66
  72
  15
  25
  66
  62
   8
  32
  61
  32
   8
  25
  48
  40
                               125

-------
Table No.l4 con't
Sample No     Time        At              Concentrate, mg/1
                         Minutes    Carbon   Carbohydrate     Protein

A-7            3:21       361         13          4              10
B-7            3:27       367         18          8              20
C-7            3:25       365         38         45              32
D-7            3:26       366         55         70              35
A-8            9:20       720         14          6               8
B-8            9:28       728         13          8              18
C-8            9:44       744         18          6              25
D-8            9:31       731         14         38              20   ,
A-9            8:10      1370         14         10              10
B-9            8:19      1379         17          6               8
C-9            8:14      1374         18         13              18
D-9            8:16      1376         14         12              13
                             126

-------
                             TABLE NO. 15
Biological Degradation of Milk Solids with Different Amounts of
Biologically Active Solids

Experiment No.  8-18-69, Test  #17

Three continuous propagators  using milk  solids feed solutions were
set up.  CP #1  ran on a 100 mg/1 milk solid solution, CP #2 on a
300 mg/1 solution  and CP  #2 on a 500 mg/1 solution.  They were
allowed to run  overnight then 100  ml aliquoto from each was filtered
on 0.45   millipore filter  pads to remove bacteria.

Two batch reactors were set ~up with innoculum taken from each
continuous propagator
Batch Reactor                     Innoculum
 A
 B
 C
 D
 E
 F

 Sample No

 A-l
 B-l
 C-l
 D-l
 E-l
 P-l
 A-2
 B-2
 C-2
 D-2
 E-2
 F-2
 A-3
 B-3
 C-3
 D-3
 E-3
 P-3
Time
:11
;20
:11
:21
10:
10;
10:
10:
10:24
10:24
12:10
12:11
12:13
12:12

12:16
 2:10
 2:11
 2:15
 2:13
 2:18
 2:19
Raw
200 ml CP#1
20 ml CP#1
200 ml CP#2
20 ml CP#2
200 ml CP#3
20 ml CP#3

    At
  Minutes
     0
     9
     0
    10
    13
    13
   119
   120
   122
   121

   125
   239
   240
   244
   242
   24?
   248
   Filtered
   0 ml
   100 ml CP#1
   0 ml
   100 ml CP#2
   0 ml
   100 ml CP#3

  Concentration, mg/1
Carbon      Carbohydrate
                           28
                           23
                           72
                           72
                           96
                           90
                           28
                           17
                           72
                           72
                           96
                           85
                           21
                           17
                           64
                           70
                           92
                           84
                27
                11
                81
                80
                86
                87
                21
                 5
                78
                80
                86
                86
                13
                 4
                76
                79
                81
                86
                               127

-------
Table No .igcon't
 Sample No        Time          At           Concentration, rng/1
                             Minutes      Carbon      Carbohydrate

 A-4               4:09         358          16             6
 B~4               4:11         360          16             5
 C-4               4:15         364          63
 DH»               4:12         36l          6?            77
 E-4               4:25         374          73            70
 F-4               4:17         366          74            86
 A-5               9:07        1376          16             4
 B-5               9t09        1378          17             7
 C-5               9:11        1380          33            36
 D-5               9:13        1382          46            56
 E-5               9:24        1393          27            18
 P-5               9:25        1394          53            67
 A-6              10:01        2870          16             5
 B-6               9:55        2864          17             7
 C-6               9:43        2852          21            13
 D-6               9:41        2850          29            33
B-6               9:33        2842          24            22
P-6               9:35        2845          28            27
                            128

-------
                             TABLE NO.  16
Effect of Substrate Concentration for Glycine Acclimated Innoculum

Experiment No. 9-22-69, Test  #19, Barch Reactor, Well Mixed
Innoculum and Concentrate  Preparation
Effluent from a  continuous propagator
solution was used.  This material was
tests.  Concentrate of glycine  (0.200
and glutamic acid (0.200 grams  in 200
pared and autoclaved
Batch Reactor              Innoculum
     A                     200 ml
     B                     200 ml
     C                     200 ml
     D                     200 ml
     E                     200 ml
                         using 100 mg/1 glycene feed
                         used as innoculum for 5 batch
                         grams in 200 ml distilled water)
                         ml distilled water) were pre-

                                 Concentrate Additions
                                 25 ml of glycine
                                 50 ml of glycine
                                 50 ml of glutamic acid
                                 25 ml of each
                                 50 ml of each
 Sample No
 A-l
 B-l
 C-l
 D-l
 E-l
 (Concentrate
 A-2
 B-2
 C-2
 D-2
 E-2
 A-3
 B-3
 C-3
 D-3
 B-3
 A-4
 B-4
 C-4
 D-4
 E-4
 A-5
 E-5
 C-5
 D-5
 E-5
   Time
   10:10
   10:10
   10:12
   10:14
   10:1?
was added
   10:21
   10:23
   10:23
   10:27
   10:28
   11:30
   11:31
   11:33
   11:35
   11:36
   12:31
   12:32
   12:36
   12:37
      :39
      :42
      :45
            St               Concentration, mg/1
         Minutes    Carbon      Ammonia    Amino Acid
                               Nitrogen    (as

                                                72
                                                93
                                                76
                                                75
                                                77
12:
 1;
 1:
 1:46
 1:49
 1:49
       0
       0
       2
       4
       7
prior to
      11
      13
      13
      17
      18
      80
      81
      83
      85
      86
     141
     142
     146
     147
     149
     212
     215
     216
     219
     219
       27
       27
       27
       28
       27
second sample)
       58           7.6
       82           5.8
       92          12.7
       89           4.7
      134          12.0
       58
       84
       95
       88
      132
       59
       84
       92
       89
      132
       62          11.0
       85           6.8
       92          12.7
       89          12.9
      132
169

152
177

167

148
176

178

153
176

168

154
183
                               129

-------
Table No.l6 con't
Sample No
A-6
B-6
C-6
D-6
E-6
A-7
B-7
C-7
D-7
E-7
A-8
B-8
C-8
D-8
E-8
A-9
B-9
C-9
D-9
E-9
A-10
B-10
C-10
D-10
B-10
A-ll
B-ll
C-ll
D-ll
E-ll
A-12
B-12
C-12
D-12
E-12
A-13
B-13
C-13
D-13
E-13
Time
  At
Minutes
2:35
2:37
2:39
2:41
2:42
,4:24
4:24
4:26
4:27
4:29
6:01
6:02
6:03
6:06
6:07
10:57
10:57
11:00
11:00
11:02
12:28
12:30
12:31
12:32
12:37
7:23
7:23
7:27
7:30
7:35
8:58
8:59
9:08
9:08
9:10
11:15
11:16
11:17
11:18
11:18
265
267
269
271
272
374
374
376
377
379
471
472
473
476
477
767
767
770
770
772
858
860
861
862
867

1273
1277
1280
1285
1368
1369
1374
1378
1380
1505
1506
1507
1508
1508
                                     Carbon
 59
 87
 93
 89
136
 59
 81
 88
 80
130
 54
 79
 85
 79
124
 51
 73
 63
 50
110
 48
 59
 64
 49
106
 37
 51
 17
 20
 71
 30
 50
 18
 19
 63
 22
 41
 20
 18
 46
Concentration, mg/1
   Ainmonla   Amlno Acid
  Nitrogen   (as glycine)

                  164

                  147
                  180
                                     ,4
                                     • 7
                                    6.3
                                   12.1
                                    6.6

                                    8.2
                          6.3
                         12.9
                         10.2
                          9.8
                         17.0
                         11.
                         14.
                         11.0
                          9.3
                         17.0
                         12.9
                         16.
                         18.
                         17.4
                         24.8
                         12.9
                         23.0
                         20.0
                         21.6
                         27-6
                         20.8
                         29.1
                         23-
                         27-
                         24.
                         19-
                                     ,5
                                     .3
                                     .7
                                     ,1
                                     ,2
                                     ,5
                                   35.2
                  164

                  148
                  177

                  163

                  147
                  177

                  162

                  129
                  162

                  159

                  128
                  163

                  105
                  179
                   55
                   74
                  185
                   83
                  167
                   48
                   52
                  173
                   66
                  142
                   38
                   40
                  151
                             130

-------
Table No. 16  con't
Sample No        Time         At
                           Minutes    Carbon    Ammonia    Amlno Acid
                                                Nitrogen    (as glycine)
A-14              1:50      1660        19          24.0          48
B-14              1:50      1660        28          31.3          77
C-14              1:55      1665        20          27.0          48
D-14              1:58      1668        17          17-7   '"       39
E-14              2:02      1672        30          37.3         102
A-15             12:47      4477        12          11.1          23
B-15             12:49      4479        16          15.2          31
C-15             12:52      4482        16          20.3          36
D-15             12:54      4484        28
E-15              1:03      4493        20          18.9          27
                                131

-------
                             TABLE NO. 1?
Effect of Substrate Concentration in Degradation of Laurie Acid

Experiment No. 1O-7-69, Test #20, Batch Reactor, Well Mixed

Effluent from a continuous propagator using 50 mg/1 lauric acid feed
was collected and used as innoculum in a series of batch tests.
Different amounts of fresh feed (50 mg/1 lauric acid) were added at
the beginning of each batch test.  The contents of the lauric acid
propagator were used as innoculum.
in lieu of concentrate.
Batch Reactor        Innoculum, ml
     A                   400
                    The aluric acid feed was used
     B
     C
     D

Sample No
Time
         200
         200
          40
  At
Minutes
          Fresh Feed, ml
                 0
               200
               200
               360
              Mixing Time
              9:44 A.M.
              9:44 A.M.
              9:49 A.M.
              9:4? A.M.
Carbon Concentration, mg/1
A-"l
B-l
CXL
D-l
A-2
B«i2
C-i2
D^-2
A"-3
A-4
C^-3
1X3
A-4
B-4
C^4
D*>4
A-5
B-5
C-5
D-^S
A-6
B-6
C-6
D-6
A-7
B-7
C-7
D-7
A-8
B^8
C-8
D-8
Footnote :
10:05
10:00
10:09
10:03
11:37
11:26
11:35
11:29
2:20
2:22
2:30
2:26
4:32
4:36
4:43
4:43
7:46
7:50
7:58
8:00
9:55
10:00
10:09
10:10
11:20
11:28
11:25
11:26
11:12
11:28
11:17
11:32
Fa'tty acid
5
1 0
9
3
97
86
95
89
260
262
270
266
392
396
403
403
586
590
598
600
715
720
729
732
1320
1528
1525
1526
2952
2968
2957
2972
analyses were erratic
                                                  19
                                                  21
                                                  31
                                                   6
                                                  14
                                                  15
                                                  25
                                                   7
                                                   7
                                                   6
                                                  19
                                                   6
                                                   5
                                                   6
                                                  15
                                                   6
                                                   6
                                                   6
                                                   6
                                                   7
                                                   5
                                                   7
                                                   7
                                                   7
                                                   5
                                                   5
                                                   5
                                                   8
                                                  10
                                                   8
                                                   4
                             132

-------
                             TABLE NO.  18

Effect of Substrate Concentration in Degradation of Laurie and
Palmitic Acid

Experiment No. 12-18-69, Test  #21, Batch Reactor, Well Mixed

Effluent from a continuous propagator using 50 mg/1 laurlc acid feed
was collected and used as innoculum in  a series of batch tests.
At the beginning  of each batch test, fresh feed solution of lauric
or palmitic  acid  were added.
Batch Reactor         Innoculum  Fresh  Peed Added at Start of Tests
                                     50 mg/1    100 mg/1   50 mg/1
                                     Lauric     Laurie'     Palmitic
     A                  190             0          0          0
     B                  190           200          0          0
     C                  190             0        200          0
     D                    50             0        350          0
     E                    50           350          0          0
     F                  100             0          0        300

 Sample  No           Time         At         Carbon Concentration, mg/1

 A-l                 10:02                           11
 B-l                 10:05                           11
 C-l                 10:05                           11
 Fresh feed added before taking sample #2
 B-2                 10:28        3                   21
 C-2                 10:35       10                   *»1
 D-2                 10:36       11                   5«
 E-2                 10:37       12                   36
 p-2                 10:38       13                   1°
 A-3                 11:00       35                   13
 B-3                 11:02       37                   24
 C-3                 11:04       39                   35
 D-3                 11:06       41                   58
 E-3                 11=12       *7                   ?2
 p_3                 11:14       49                   1'
 A-4                 12:00       95                   H
 B-4                 12:02       97                  23
 C-4                 12:04       99                   34
 D-4                 12:06      101                   56
 E-4                 12:13      108      •             32
 F-4                 12:15      HO                   ^
 A-5                   I'M      159                   oo
 B-5                   1 = 06      161                   22
 C-5                   1:08      163                   30
 D-5                   1=10      165                   53
                       1 = 15      170                   26
                       1:17      172                   17
                               133

-------
Table No. 18  con't
Sample No

A-6
B-6
C-6
D-6
E-6
F-6
A-7
B-7
C-7
D-7
E-7
F-7
A-8
B-8
C-8
D-8
E-8
F-8
A-9
B-9
C-9
D-9
E-9
F-9
A-10
B-10
C-10
D-10
E-10
F-10
A-ll
B-ll
C-ll
D-ll
E-ll
F-ll
A-12
B-12
C-12
D-12
E-12
F-12
Time
At
3:00
3:02
3:04
3:06
3:12
3:14
5:00
5:02
5:04
5:08
5:16
5:18
7:45
7:45
7:50
7:50
8:00
8:00
10:20
10:20
10:30
10:30
10:35
10:35
9:13
9:15
9:17
9:19
9:24
9:28
12:00
12:02
12:04
12:06
12:14
12:16
3:30
3:32
3:34
3:36
3:50
3:54
275
277
279
281
287
289
395
397
399
403
411
413
560
560
565
565
575
575
715
715
725
725
730
730
136
1370
1372
1374
1379
1383
1535
1537
1539
1541
1549
1551
1745
1747
1749
1751
1765
1769
Carbon Concentration, mg/1
                                 19
                                 25
                                 48
                                 26
                                 16

                                 13
                                 17
                                 42
                                 21
                                 12
                                  1
                                  2
                                  3
                                 33
                                 14
                                  6
                                  1
                                  0
                                  0
                                 14
                                  4
                                  4
                                  0
                                  0
                                  0
                                  4
                                  2
                                  2
                                  1
                                  1
                                  1
                                  3
                                  2
                                  2

                                  1
                                  1
                                  2
                                  1
                                  3
                              134

-------
Table No. 18  can't
Sample No           Tome         At        Carbon Concentration, mg/1

B-13                11:45      2960                   5
C-13                11:58      2973                   3
D-13                12:10      2985                   2
B-13                11:52      2967                   5
F-13                11:50      2965                   5

Analysis of  feed solutions  (F  =  filtered, UP = unfiltered)
50mg/l Laurie UP   10:15                            35
50mg/l Laurie P    10:15                            35
lOOmg/1 Laurie  UP  10:15                            65
100mg/l Laurie  F   10:20                            65
50mg/l Palmitic UP 10:20                            33
50mg/l Palmitic F  10:18                            15
 Footnotes:   Temperature was approximately 24°c
             Cell mass determination by millipore  filtration
 Reactor Sample            Suspended Solids
                           Concentration-, mg/1
      A                           4
      B                          18
      C                          22
      D                          48
      E                          32
      p                          16
                               135

-------
                             TABLE NO. 19
Effect of Substrate Concentration on Degradation of Palmitic and
Laurie Acid.

Experiment No. 12-23-69, Test #22, Batch Reactor, Well Mixed

Effluent from a continuous propagator using 50 mg/1 palmitic acid
feed solution was collected and used as innoculum in a series of
batch tests.  At the beginning of each batch test, fresh feed
solutions of lauric or plamitic acid were added.

Fresh feed added at start of test
Reactor    Innoculum     Lauric Acid Feed (m/1)    Palmitic Peed
   A
   B
   C
   D
   E
   F

Sample No

A-l
B-l
C-l
D-l
E-l
F-l
A-2
B-2
C-2
D-2
E-2
F-2
A-3
B-3
C-3
D-3
E-3
F-3
A-4
B-4
C-4
D-4
E-4
F-4
200
200
200
 50
 50
100

lime
10;
10;
10;
10:
10;
   25
   24
   26
   32
   44
10:55
11
11
11
11
11
12
12
12
12
12
12
 1
 1
 1
 1
 1
   29
   30
   31
   39
   45
   20
   21
   22
   23
   29
   51
   30
   21
   22
   23
   35
 1:49
50 mg/1
    0
  200
    0
    0
  350
    0

   At

    1
    0
    2
    8
   20
   31

   65
   66
   67
   75
   81
  116
  117
  118
  119
  125
  147
  206
  177
  178
  179
  191
  205
                        100 mg/1
                            0
                            0
                          200
                          350
                            0
                            0
             50 mg/1
                 0
                 0  •
                 0
                 0
                 0
               300 ml
Carbon Concentration, mg/1

           5
          20
          34
          54
          34
          15

          14
          28        '•  :
          41       •••-•
          21
           8
           O         -"•
           7
          20
          48
          23
           8
           6
           4
          12
          45
          21
           6
                              136

-------
Table No-19  cpn't
Sanple No     Time           At           Carbon Concentration

A-5            3:26        302                      3
B-5            3:14        290                      3
C-5            3:28        304                      4
D-5            3:11        287                     34
E-5            3:39        315                     14
F-5            3:39        315                      5
A-6            4:45        381                      3
B-6.            4:42        378                      3
C-6            4:57        393                      4
D-6            4:52        388                     23
E-6            5:06        402                      4
P-6            5:1^        410                      3
A-7            8:10        586                      0
B-7            8:15        591                      0
C-7            8:20        596                      2
I>7            8:20        596                      5
E-7            8:30        606                      2
F-7            8:30        606                      2
A-8            9:50        686                      2
B-8            9:50        686                      2
C-8            9 = 55        691                      2
D^8            9:55        691                      5
E-8            10:10        706                      2
F-8            10:10        706                      2
A~9            9:24        1380                      3
B-9            9:25        1381                      3
C-9            9:26        1382                      4
M            9:27        1383                      3
E-g            9:48        1404                      2
p-9            9:50        1406                      3
A-10          12:00        1536                      ^
B-10          12:01        1537                      2
C-10          12:02        1538                      3
D-10          12:03        1539                      2
E-10          12:24        1560                      3
jui            12:25        1561                      3
                              137

-------
Table No. ig con't
Sample No     Time
B-ll
C-ll
D-ll
E-ll
F-ll
             At
 :58
 ;59
 ;QQ
 ;02
3:18
1715
1716
1718
1734
               Carbon Concentration, nig/1
3
3
0
3
Footnotes:  Temperature was approximately 25° c
            Analysis of feed solution (F = filtered, UP = unfiltered)
            50 rag/1 Laurie Feed UF                 37
            50 mg/1 Laurie Feed F                  38
            100 mg/1 Laurie Feed UF                64
            100 mg/1 Laurie Feed F                 62
            50 mg/1 Palmitic Feed UF               28
            50 mg/1 Palmitic Feed F                15
            Cell Mass Determination by millipore filtration
                              138

-------
                             TABLE NO •  20
Effect of Substrate Concentration  on Rate  of Degradation of Mixed
Peed Solutions

Experiment No.  12-30-69, Test No.  23,  Batch Reactor, Well Mixed

Effluent from a continuous propagator  using 50 mg/1 lauric acid
feed solution was  collected and used as innoculum in a series of
batch tests.  At the  beginning  of  each test, fresh feed solutions
were added as shown:
                              Concentration
Feed Solutions
Lauric Acid
Glutamic
Glucose
Reactor

A
B
C
D
E
Sample
A-l
B-l
0-1
D-l
E-l
A-2
B-2
0-2
D-2
E-2
A-3
B-3
0-3
D-3
E-3
A-4
B-4
C-4
D-4
E-4
A-5
B-5
0-5
E-5
Acid



Innoculum
ml
200
200
200
200
200
Time
9:00
9:00
9:01
9:01
9:02
9:19
9:20
9:20
9:21

10:00
10:01
10:02
10:03
10:08
11:00
11:01
11:02
11:03
11:11
12:00
12:01
12:02
12:03
12:15






At
0
0
1
1
2
19
20
20
21

60
61
62
63
68
120
121
122
123
131
180
181
182
183
195
                               100 mg/1
                               1000 mg/1
                               1000 mg/1
                                  Fresh Feed Solutions  Added,.ml
                            Lauric Feed   Glucose Feed   Glutamic Feed
                               200            0              0
                               200           50              0
                               200            0              50
                               200           50              50
                               200            0              0
                                                           Glutamic
                                                         Concentration
                                                             mg/1
                                                            108
                                                             81
Carbon
Concentration
mg/1
3
3
3
4
6
23
74
61
95
26
75
63
97
3
16
68
57
87
1
6
55
44
77
1
Glucose
Concentration
mg/1

0

0


72

70

74

71


73

61


71

67

                                                            107
                                                             99
                                                            106
                                                            102
                                                             92
                                                             97
                               139

-------
Table No. 20  con't

Sample     Time     At        Carbon       Glucose        Glutamlc
                           Concentrate   Concentrate    Concentrate
                               mg/1          mg/1           mg/1
                                 4
                                47            66
                                37                          98
                                67            32            71
                                 3            32            71        t
                                 4
                                39            ^5
                                23                          87
                                47            13            83

                                 4             0
                                13             1
                                 7                          66
                                10             1            68
                                 4
                                 4
                                 6             2
                                 8                          71
                                 8             9            80
                                 4
                                 5
                                 5             2
                                 7                          88
                                 6             1            65
                                 4

                                 4             1
                                 6                          72
                                 7             1            74
                                 5
                                 3
                                 2             0
                                 5                          85
                                 3             8            75
                                 2
                                 7
                                10             8
                                10                          80
                                10             8            83

Footnotes:   a) Temperature was approximately 28°c, b) Suspended solids
(cell mass) was measured by filtering through a membrane filter and
weighing the dry mass.  Reactor            Suspended Solids, mg/1
                          B                      34
                          C                      34
c) High amino acid concentration is due to  presence of ammonia nitrogen
Sample                   C-l    C-6   C-ll  D-l    D-5   D-10
Arrmonia Nitrogen, mg/1   106.5  80.5  95-0  115.5  85.0  78.5


                              140
A-6
B-6
C-6
D-6
E-6
A-7
B-7
C-7
D-7
E-7
A-8
B-8
C-8
D-8
E-8
A-9
B-9
C-9
D-9
E-9
A-10
B-10
C-10
D-10
E-10
A-ll
B-ll
C-ll
D-ll
B-ll
A-12
B-12
C-12
D-12
E-12
A-13
B-13
C-13
D-13
1:00
1:01
1:01
1:02
1:24
1:59
2:00
2:01
2:02
2:28
4:30
4:41
4:36
4:57
4:41
6:40
6:41
6:42
6:43
7 = 13
9:15
9:16
9 = 17
9:18
9:48
9:04
9:05
9:26
9:07
9:32
2:05
2:17
2:15
2:35
2:09
2:29
2:34
2:58
3:20
240
241
241
242
264
299
300
301
302
328
450
461
456
477
461
580
581
582
583
613
735
736
737
738
768
1444
1445
1446
1447
1472
1745
1757
1755
1777
1749
4649
4654
4678
4700

-------
                             TABLE NO.  21

Effect of Substrate Concentrations on Rate of Degradation of Mixed
Feed Solutions.

Expertaent No. 1-29-70, Test No.  24, Batch Reactor, Well Mixed

Effluent from a  continuous propagator using 50 mg/1 lauric acid feed
solution was  collected and used on innoculum in a series of batch
tests.  At the beginning  of each  test,  fresh feed solutions were
added as shown.
           Feed  Solution                      'Concentration, mg/1
           Lauric Acid                             100
           Glutamic Acid                            1000
           Glucose                                 1000
Reactor   Innoculum  (ml)        Fresh Feed Solutions Added
                           Lauric Feed    Glucose Feed   Glutamic Feed
   A           200            200  ml            0 ml          0 ml
   B           200            200  ml            50 ml          0 ml
   C           200            200  ml            0 ml         50 ml
   D           200            200  ml            50 ml         50 ml
   E           200              0  ml            0 ml          0 ml

 Sample    Time      -At       Carbon          Glucose    Glutamic Acid
                             Concentrate    Concentrate   Concentrate
                               (mg/1)           (mg/1)        (mg/1)
 A-0        10:48      0         12
 B-0        10:48      0         16                2
 C-0        10:49      1         14                          .12
 D-0        10:49      1         14                8             20
 E-0        10:54      6         14
 A-l        11:00     12         35
 B-l        11:01     13         79              78
 0-1        11:02     14         63                            72
 D-l        11:04     16         96              73             87
 E-l
 A-2        11:55     67         37
 B-2        11:56     68         77              80
 0-2        11:57     69         59                             90
 D-2        11:58     70         97              79             »?
 E-2        12:01     73         12
 A-3          1=06    138         29
 B-3          1:07    139         70              81
 0-3          1=08    140         53                             89
 D-3          1 = 09    1^1         90              77             88
 E-3          1=15    1^7          9
 A-4          2:00    192         25
 B-4          2:01    193         
-------
Table No. 21  con't
Sample


A-5
B-5
C-5
D-5
E-5
A-6
B-6
C-6
D-6
E-6
A-7
B-7
C-7
D-7
E-7
A-8
^8
C-8
D-8
E-8
A-9
B-9
C-9
D-9
E-9
A-10
B-10
C-10
D-10
E-10
overnight
A-ll
B-ll
C-ll
D-ll
E-ll
A-12
B-12
C-12
D-12
E-12
Ttaie


3:04
3:05
3:06
3:07
3:12
4:03
4:05
4:07
4:09
4:12
6:25
6:25
6:30
6:30
6:35
8:02
8:03
8:04
8:05
8:16
9 = 57
9 = 58
9:59
10:00
10:08
11:59
12:00
12:03
12:05
12:11
1/29 to
10:27
10:32
10:39
10:54
10:31
12:48
12:52
1:00
1:07
12:50
At


256
257
258
259
264
315
317
319
321
324
457
457
462
462
467
554
555
556
557
568
669
670
671
672
680
791
792
795
797
803
1/30
1419
1424
1431
1446
1423
1560
1564
1572
1579
1562
Carbon
Concentrate
(jflg/D
16
56
44
79
5
14
55
40
76
5
11
54
24
57
4
9
51
10
40
4
6
49
9
23
4
H
45
9
18
6

5
39
10
14
8
5
33
10
13
9
                                             Qlucose    Qlutamlc Acid
                                           Concentrate   Concentrate
                                                           , (mg/D
                                               80
                                                              74
                                               81             55
                                               79
                                                              70
                                               79             69
                                               80
                                                              44
                                               73             45
                                               77
                                                              20
                                               43             28
                                               78
                                                              21
                                                9             26
                                               70
                                                              21
                                                2             12
                                               26
                                                              25
                                                3             18
                                               21
                                                              25
                                                5             11
                             142

-------
Table  No.  21 con't


Sample     Time      At        Carbon         Giucose     Qlutamic Acid
                             Concentrate     Concentrate    Concentrate

A-13         9:45   2757          g  )          CinS/1)         (rng/1)
B-13         9:46   2758          5               ?
C-13         9:47   2759          9                             ^
D-13         9:48   2760         u               n             ft
E-13        10;05   2777          8
Footnotes:  a) Temperature was maintained  at approximately 27°c
            b) Suspended  solids were measured by membrane filtration
and dry weighing
          Reactor                   Suspended Solids, mg/1
          __                                  g

            B                                 34
            C                                 26
            D                                 58
            E                                  4
c) Greenish tint developed in Reactor C and D after 12 hours
d) Glucose analysis by phenol sulfuric acid test
                             143

-------
                             TABLE NO. 22
Effect of Substrate Concentration on Rate of Degradation of Mixed
Peed Solutions

Experiment No. 2-23-70, Test No. 25, Batch Reactor, Well Mixed

Effluent from a continuous propagator using a mixed feed consisting
of 100 mg/1 lauric acid, 100 mg/1 glutamic acid and 100 mg/1 of
glucose was collected and used as innoculum in a series of batch
tests.  At the beginning of each test, fresh feed solutions were
added as shown:
           'Feed Solutions            Concentration, mg/1
           Lauric Acid
           Glutamic Acid
           Glucose
           Inncoulum (ml)
Reactor
  A
  B
  C
  D
  E

Sample
A-0
B-0
C-0
D-0
E-0
A-l
B-l
C-l
D-l
E-l
A-2
B-2
C-2
D-2
E-2
A-3
B-3
C-3
D-3
E-3
              200
              200
              200
              200
              200
           Time
           10:48
           10:49
           10:50
                     At
0
1
2
10:51
11:49
11:49
11:50
11:50
11:51
1:02
1:09
1:21
2:26
2:28
2:30
2:34
3:31
3:43
3:49
3
61
61
62
62
63
134
141
153
218
220
222
226
283
295
301
                    1000
                    1000
            Freeh Feed Solutions Added
     Lauric Feed   Glucose Feed    Glutamic Feed
       (ml)            (ml)           (ml)
         0              25              0
         0               0             25
       200               0              0
       200              25             25
         000
   Carbon
Concentrate
   (mg/1)
    44
    42
    42

    41
    76
    58
    42

    34
    72
    45
    35
    35
    22
    63
    20
    27
    27
    18
  Glucose
Concentrate
   (mg/1)
    34
                                    Glutamic Acid
                                     Concentrate
                                        (mg/1)
                                                89


                                                67

                                                74


                                                30

                                                68


                                                 9
                                         70

                                         45
                                         13

                                          5
                              144

-------
Table No. 22 con't
Sample

i
A-4
B-4
C-4
D-4
E-4
A-5
B-5
C-5
D-5
E-5
A-6
B-6
C-6
D-6
E-6
A-7
B-7
c-7
D-7
E-7
A-8
B-8
c-8
D-8
B-8
A-9
B-9
C-9
D-9
E-9
A-10
B-10
C-10
D-10
E-10
Time


;io
4:22
4:53
5:14
5:18
7:24
7:25
7:26
7:27
8:06
9:38
*9:39
9:40
9:41
10:40
9 = 30
9:30
9:31
9:32
10:15
12:05
12:06
12:07
12:08
12:46
2:28
2:29
2:30
2:31
3:18
9:52
9:53
9:54
9:55
10:24
At


322
334
365
386'
390
516
517
518
519
558
650
651
652
653
712
1362
1362
1363
1364
1407
1517
1518
1519
1520
1558
1660
1661
1662
1663
1710
2824
2825
2826
2827
2856
Carbon
Concentrate
Crag/1)
58
16
24
12
13
45
15
17
11
13
' 40
15
11
7
13
20
21
6
11
16
13
21
7
8
15
11
20
7
10
15
12
21
7
11
15
                                               Glucose     Glutamlc Acid
                                             Concentrate    Concentrate
                                                Org/l)         (mg/1)
                                                 43
                                                  7
                                                                12

                                                  0              4

                                                 21
                                                                14

                                                 12              6

                                                 25
                                                                22

                                                 80              4

                                                 23
                                                                21

                                                 34              6

                                                 11
                                                                26

                                                 12             12

                                                 14
                                                                16

                                                  8             19
                               145

-------
Table No. 22  con't


Sample     Time      At   ,     Carbon         Qyucgs.e     Qlutaraic Acid
                            Concentrate     Concentrate    Concentrate
                               Crag/1)          (jng/1)
A-ll       10:17   4289         15              19
B-ll       10:18   4290         20                             11
C-ll       10:19   4291          7
D-ll       10:20   4292         11               3             24
E-ll       10:58   4330         16
 Footnotes:  a) Temperature was approximately 2? c
 b)   Suspended solids were measured at the end of each test  by
 filtering through a membrane filter and dry weight
      Reactor             Suspended Solids Concentrate3 rng/1
         A                           112
         B                           102
         C                            50
         D                            92
         E                            96
 c)  Some protozoa were detected in batch tests B, C3  D,  and E
                              146

-------
                             TABLE NO.  23
Effect of Substrate Concentration  on Rate of Degradation of Mixed
Peed

Experiment No.  4-30-70, Test No. 26, Batch Reactor, Well Mixed

Effluent was  collected from a  continuous propagator using a mixed
feed solution of 100  mg/1 each of  glucose, glutamic acid and lauric
acid and was  used as  innoculum in  a series of batch tests.  Fresh
feed solutions were added at the beginning of each batch test as
shown:
       Fresh  Feed Solution
       Lauric Acid
       Glutamic Acid
       Glucose
 Reactor
   A
   B
   C
   D
   E

 Sample
 A-0
 B-0
 C-0
 D-0
 E-0
 A-l
 B-l
 C-l
 .D-l
 E-l
 A-2
 B-2
 C-2
 D-2
 E-2
 A-3
 B-3
 C-3
 D-3
 E-3
Innoculum
   (ml)
  200
  200
  200
  200
  200

Time
At
1:08
1:04
1:06
1:08
1:15
1:43
1:44
1:45
1:44
1:44
4:39
4:37
4:45
4:45
5:00
6:08
6:06
6:12
6:16
6:39
4
0
2
4
11
39
40
41
40
40
175
173
181
181
196
304
302
308
312
335
               Concentration, mg/1
                     100
                    1000
                    1000
               Fresh Feed Solution Added
            Lauric        Glucose       Glutamic
         Concentrate    Concentrate   Concentrate
             (ml)           (ml)           (ml)
             200             0             0
             200             50             0
             200             0            50
             200             50            50
               000
   Carbon
Concentrate
   (mg/1)
    39
    37
    37
    37
    39
    ^5
    72
    66
   . 93
    47
    45
    71
    43
    76
    33
    33
    65
    27
    59
    27
  Glucose
Concentrate
   (mg/1)

    33-8

    25.0


    70.0

   .80.0


    95-0

    80.0


    70.0

    77.0
Glutamic Acid
 Concentrate
    (mg/1)
                                                     5
                                                     7
                                                    73
                                                    45
                                                    40
                                                    10
                                                     8
                               147

-------
Table No. 23 con't
Sample     Time      At        Carbon         Qlucose     Glutami.c Acid
                            Concentrate     Concentrate    Concentrate
                               (jng/1).          (jng/1)         (mg/1)
A-4         7:38    394         30
B-4         7:39    395         56              47.3
C-4         7:40    396         14                              8
D-4         7:41    397         38              56.3           10
E-4         7:42    398         24
A-5        10:30    566         22
B-5        10:30    566         51              81,3
C-5        10:32    568         10                             12
D-5        10:32    568         22              25.6           10
E-5        10:34    570         14
A-6         9:10   1206
B-6         9:11   1207         34              48.8
C-6         9:11   1207         10                             13
D-6         9=23   1219         10              15.0            5
E-6         9:23   1219         10
A-7         4:22   1638         15
B-7         4:23   1639         28              42.3
C-7         4:23   1639         11                             11
D-7         4:32   1648         13              22.0            8
E-7         4:32   1648         10
A-8         1:06   2882         12
B-8         1:20   2896         16              19.0
C-8        12:58   2874         12                             12
D-8         1:20   2896         13              20.0           13
E-8         1:11   2887         12
                             148

-------
                             TABLE NO.  24
Effect of Substrate Concentration on Rate of Degradation of Mixed
Feed

Experiment No. 5-21-70, Test  #273 Batch Reactor, Well Mixed

Effluent was  collected from a continuous propagator using a mixed
feed of 1QO mg/1  each of  glucose, glutamic acid and lauric acid and
was used as innoculum in  a series of batch tests.  Fresh solutions
were added to at  the  beginning of each batch test.

              Feed Solution            Concentration, mg/1
              Lauric Acid                   100
              Glutamic Acid               1000
              Glucose                      1000

Reactor       Innoculum                Feed Solutions Added
                (ml)        Lauric Feed   Glucose Feed    Glutamic Feed
                              (ml)            (ml)            (ml)
   A            200            0              0              25
   B            200            0             25               0
   C            200           200              0               0
   D            200           200             25              25
   E            200            0              0               0

 Sample   Time        At        Carbon        Glucose     Glutamic Acid
                            Concentrate    Concentrate    Concentrate
                               (mg/1)          (mg/1)         (mg/1)
 A-0      11:59      12         11                            92
 B-0      11:52       5         10              6
 C-0      11:48       1           9
 D-0      11:50       3         11              **
 E-0      11:47       0         11
 A-l      12:27      40          39                           141
 B-l      12:30      43          30             45
 C-l      12:23      36          27
 D-l      12:22      35         ^8             23
 E-l      12:27      40           9
 A-2       2:44     177          H                           117
 B-2       2:53     186          7             12
 C-2       2:38     171         12
 D-2       2:41     174          14               3
 £-2       2:43     176          7
 A-3       6:50     423          8                          160
 B-3       6:55     428          7               6
 0-3       6:40     413          6
 D_3       6:42     415          8              2
 E-3       6:44     417          6
                              149

-------
Table No. 24 can't
Sample


A-4
B-4
C-4
D-4
E-4
A-5
B-5
C-5
D-5
E-5
A-6
B-6
C-6
D-6
E-6
A-7
B-7
C-7
D-l
E-7
Time '


8:53
8:57
8:43
8:49
8:47
11:07
11:08
10:50 '
10:50
10:51
1:33
1:36
1:25
1:28
1:28
2:50
2:56
3:43
3:49
2:48
At


546
550
536
542
540
680
681
663
663
664
826
829
818
821
821
1623
1629
1616
1622
1621
Carbon
Concentrate
(ms/ll
11
10
7
8
7
8
10
7
8
7
10
6
6
6
8
7
6
7
8
5
                                             Qlucose
                                           Concentrate
                                              (mg/1)
Glutamic Acid
 Concentrate
    (rag/1)
    135
                                                             140
                                                8

                                                2



                                                0

                                                2



                                                0

                                                0
    127
    103
Footnotes:  a) Sample D-l foamed when glutamic acid was added and some
               foam was lost
                             150

-------
                             TABLE NO .  25


Effect of Substrate Concentration on Rate of Degradation Using
Mixed Peed and Excess Ammonia Nitrogen

Experiment No. 6-19-70, Test #29, Batch Reactor, Well Mixed

Effluent was  collected from a continuous propagator using a mixed
feed of 100 mg/1 each of glucose, glutamic acid and lauric acid
and was used  as innoculum  in a series of batch tests.  Fresh solutions
were added to at the beginning of each  batch test.

         Peed Solutions             Concentrations, mg/1
         Glutamic  Acid                    200
         Lauric Acid                      200
         Glucose                          200
         NHjjCl                           200

Reactor Innoculum   Lauric      Glucose    Glutamic Acid   NK^Cl
            ml      Concentrate   Concentrate   Concentrate  Concentrate
                        ml         ml            ml           ml
   A        100          200           0             0          100
   B        100            0         200             0          100
   C        200            0           0            200            0

Sample  Time       At          Carbon        Glucose     Glutamic Acid
                              Concentrate    Concentrate    Concentrate
                                 (mg/1)          (mg/1)         (mg/1)
A-0       9:55        0            10             16            165
B-0       9:58        0            12             16            112
C-0      10:04        0            13             16            Ho
A-l      10:12        2           128
B-l      10:10        0            64             51
C-l      10:10        0            56
A-2      11:18      68          123
B-2      11:20      70            60             53
 C-2      11:18      68           53
          12:39
 B-3      12:42     152           57             37
 0-3      12:59     169           *»?                          153
 A-4       1:48     218           94
 B-4       1:55     225           ^             ^
 C-i,       1:59     229            O                            72
           US                      *
 C-5       2:49     279           31
 A-6       3:52     342           g
 B-6       4:00     350           27              (
 C-6       4:00     350           24
                              151

-------
Table No. 25  can't
Sample   Time        At          Carbon          Gfluco.se     Glutamlc Acid
                               Concentrate     Concentrate    Concentrate
                                 Ong/1)          (ing/1)          (mg/1)
                                  56
                                  27               8
                                .  20                             50
                                  41
                                  20               6
                                  15                 ••         '71
                                  38
                                  19          -9         ,   •::•:,.;•.;
                                  12                             59
                                  33
                                  11               7
                                   9               •              77
                                  29
                                  15               8
                                   9                             75
                                  30                                :
                                  10             '  8
                                   7                             92
                                  32
                                   9               7
                                   9                             62
A-7
B-7
C-7
A-8
B-8
C-8
A-9
B-9
C-9
A-10
B-10
C-10
A-ll
B-ll
C-ll
A-12
B-12
C-12
A-13
B-13
C-13
4:48
4:52
4:52
8:31
8:32
8:33
10:33
10:30
10:37
12:22
12:21
12:23
9:47
9:45
9:45
8:15
8:13
8:13
6:43
6:43
6:43
398
402
402
621
622
623
743
740
747
852
851
853
1417
1415
1415
2045
2043
2043
3397
3393
3393
                             152

-------
                             TABLE NO.  26
Effect of Substrate Concentration on Rate of Degradation Using lyiixed
Feed and Excess Attimonia Nitrogen

Experiment No. 7-15-70, Test No. 30, Batch Reactor, Well Mixed

Effluent was collected from a  continuous propagator using a mixed
feed of 100 mg/1  each, of  glucose, glutamic acid and lauric acid
and was used as innoculum in a series of batch tests.  Fresh solutions
were added to  at  the  beginning of each batch test.

         Feed  Solutions          Concentration,
         Lauric Acid                  1000
         Glutamic Acid                1000
         Glucose                      1000
         Ammonium Chloride           1000

Reactor Innoculum        Lauric      Glucose    Glutamic Acid  NtLCl
           Volume      Concentrate   Concentrate   Concentrate   Volume
              (ml)        Volume(ml)   Volume(ml)    Volume(ml)   (ml)
   A          340             40           0              0         20
   B          340              0'         40              0         20
   C          360              0           0             40          0
   D          280             40          40             40          0

 Sample  Time        At          Carbon         Glucose     Glutamic Acid
                               Concentrate   Concentrate    Concentrate
                                 (mg/1)          (mg/1)          (mg/1)
 A-0       11:30       0           79             30              4
 B-0       11:30       0           78             55              20
 C-0       11:30       0           76             33              22
 D-0       11:30       0           80             75              2B
 A-l       12:05      35          129
 B-l       12:05      35          H7            I40              R
          IP-OR      35           98                            |°
          lillO      40          160            135              87
 A-2        1*09      99          120
 B-2        It 10     100          105            128
 C-2        1:11     101           94                            68
 D-2       1:12     102          155            139              87
 A-3       2:19     169          H°             ,
           2:20     170           99            125
           2-20     170           87                            51
           2:17     167          15J            133             *
 A-4       3:17     227          13J
 B-4       3:18     228           94            116
 C-4       3:19     229           77
 D-4       3:45     245          167
                              153

-------
Table No. 26  con't
Sample   Time
At
A-5
B-5
C-5
D-5
A-6
B-6
C-6
D-6
A-7
B-7
C-7
D-7
A-8
B-8
C-8
D-8
A-9
B-9
C-9
D-9
A-10
B-10
C-10
D-10
A-ll
B-ll
C-ll
D-ll
A-12
B-12
C-12
D-12
A-13
B-13
C-13
D-13
4:11
4:13
4:14
4:18
5:45
5:46
5:47
5:50
6:05
6:08
6:15
6:18
8:25
8:27
8:32
8:30
9:35
9:36
9:37
9:31
10:25
10:26
10:26
IP: 27
9:46
9:47
9:47
9 = 50
4:23
4:23
4:21
4:27
9:38
9:35
9:37
9:50
281
283
284
288
375
376
377
380
395
398
405
408
535
537
542
540
605
606
607
601
655
656
656
657
1336
1337
1337
1340
1733
1733
1731
1737
2768
2765
2767
2780
  Carbon
Concentrate
  (rag/1)
   98
   83
   63
  149
   80
   63
   49
  133
  126
  114
   95
  187
   42
   45
   30
  109
   32
   39
   31
  115
   31
   28
   32
  107
   24
   20
   31
   62
   24
   20
   34
   47
   21
   17
   31
  Qlucose
Concentrate
  Crag/1)

  109

  125

   88

  108

   87

   87

   47

   93

   22

   68

   10

   48

    2

    5

    2

    7

    4

    2
Qlutaraic Acid
 Concentrate
   (rag/D
                                                               17
                                                               22
                                                                6
                                                                7


                                                               16
                                                                9
                                                                5
                                                                6
                                                                5
                                                                7
                                                                5
                                                                5
                                                                8
                                                                6
                                                               16
                                                                6
                                                               18
                                                                6
Footnotes:  Temperature was approximately 30°c-at the end of each test
the material was filtered and dried to measure suspended-solids (cell
mass)
        Reactor                 Suspended Solids,, mg/1
          A                              H8
          B                               84
          C                               50
          D                              152
                             154

-------
                                     TABLE NO
            27
        Effect of Substrate Type on Rate of Degradation Using Mixed Liquor
        Activated Sludge from Minneapolis-St. Paul Sewage Treatment Plant

        Experiment No. 7-23-70, Test #31, Batch Reactor, Well Mixed

        Mixed liquor was obtained from the treatment plant at about 9:00 A.M.
        Aliquots were used as innoculum of six batch reactors.  Feed solutions
        were added as shown.
        Feed Solutions                     Concentration, mg/1
        Glucose                                1000
        Starch                                 1000
        Glutamic Acid                          1000
        Peptone                                1000
        Laurie Acid                             100
        Reactor
           A
           B
           C
           D
           E
           F
Innoculum
Used

200
200
200
200
200
200

Glucose
(ml)
50
0
0
0
0
25
       Feed Solutions  Added
   Starch  Glutamic Acid  Peptone
     (ml)
       0
      50
       0
       0
       0
       0
(ml)
  0
  0
 50
  0
  0
 25
 (ml)
   0
   0
   0
  50
   0
   0
Laurie Acid
   (ml)
     0
     0
     0
     0
   200
    50
Sample Time  At Carbon Inorganic Protein Glucose Glutamic Carbohydrate Ammonia Starch
  No
AI
BI
CI
DI
El
AO
BO
CO
DO
EO
FO
Al
Bl
Cl
Dl
El
Fl
Min






1:25 0
1:25 0
1:25 0
1:25 0
1:43 18
1:40 15
2:45 80
2:45 80
2:45 80
2:45 80
2:57 92
2:53 88
Total
mg/1
89
93
96
93
93
132
135
132
159
89
129
111
119
114
119
34
94 -
Carbon
mg/1
26
27
27
27
27
21
26
21
26
30
27
21
19
24
23
31
25
mg/1    mg/1
250
        128
         54
         95
190
 Acid
 mg/1
                  5
                  7
 150
  59

  74
                125
                 28
mg/1

  7
  7
            152
             18
            111
            146
   mg/1    mg/1
                        7.0
                        6.6
            4.9
            9.0

            9.5
                        9
                       11
                        2.3
                                     155

-------
Table No.  27 con't
     At Carbon Inorganic Protein Glucose Glutamic Carbohydrate Ammonia Starch
                           mg/1    mg/1    Acid       mg/1       mg/1    mg/1
                                           mg/1
                                    78                 98
                                                      130                  0
                                           101
                           270              30

                                     4       3
                                    57                 87
                                                      132                  0
                                            58                   14.3
                           255              34                   12.9

                                     7       3                    2.7
                                    21                 47                  0
                                                      120
                                            22
                           235              25
                                     7                 20
                                                      122
                                            17                   11.8
                           225              20                   10.5

                                     6       3                    3.0
                                     4                 21
                                                      112
                                            18
                           215              16

                                     6       2
                                     5                 15
                                                      124
                                            15
                           205              16

                                     6       7
                                     5                 19 . "    -
                                                      118
                                            11
                           199              18
Footnotes:  Temperature was approximately 28°c
            Volatile suspended solids of inncoulum was 670 mg/1
            Total suspended solids of innoculum was 837 mg/1
                            156
Sample Time At
No

A2
B2
C2
D2
E2
P2
A3
B3
C3
D3
E3
P3
A4
B4
C4
D4
E4
F4
A5
B5
C5
D5
E5
F5
A6
B6
C6
D6
E6
F6
A7
B7
C7
D7
E7
F7
A8
B8
C8
D8
E8
F8
Min

3:45 140
3:45 140
3:45 140
3:45 140
3:55 150
3:57 152
4:55 210
4:53 208
4:56 211
4:57 212
5:03 218
5:02 217
7:15 350
7:15 350
7:20 355
7:23 358
7:25 360
7:25 360
9:04 459
9:04 459
9:06 461
9:06 461
9:07 462
9:07 462
10:45 560
10:46 561
10:45 560
10:54 569
10:50 565
10:49 564
9:23 1198
9=23 1198
9:26 1201
9:31 1206
9:31 1206
9:32 1207
4:03 1598
4:03 1598
4:03 1598
4:10 1605
4:12 1607
4:12 1607
Carbon
Total
mg/1
108
89
105
111
94
81
94
108
86
103
94
81
81
111
81
100
100
78
75
105
81
97
105
81
75
100
75
86
103
73
75
105
78
86
94
75
75
100
81
86
84

Inorgan:
Carbon
mg/1
20
20
25
25
30
25
20
19
22
22
32
25
19
20
23
23
32
24
19
20
21
21
32
23
19
20
22
21
32
24
21
21
23
23
34
25
20
21
22
21
26
34

-------
                             TABLE NO.  28
Effect of Substrate Type on Rate of Degradation Using Mixed Liquor
Activated Sludge from Minneapolis-St. Paul Sewage Treatment Plant

Experiment No. 8-11-70, Test #32, Batch Reactor, Well Mixed

Mixed liquor was obtained from the treatment plant at 10:00 A.M.
just prior to start of the test.  Aliquots were used as innoculum
for each batch reactor.  Peed solutions were added at the beginning
of each test as shown.  A second addition of fresh feed solution
was also made after sample number five (after about 7 hours)
Feed Solutions                   Concentration, mg/1
Glucose                                  1000
Starch                                   1000
Glutamic Acid                            1000
Peptone                                  1000
Laurie Acid                               100
Anmonium Chloride                        1600
Reactor  Innoculum                 Feed Solutions Added, ml
            ml      NHnCl.  Glucose  Starch  Glutamic  Peptone  Laurie
                                              Acid              Acid
   A
   B
   C
   D
   E
   P
   G
200
200
200
200
200
200
200
5
5
0
0
5
5
5
 0
 0
 0
 0
20
 0
 0
40
 0
 0
 0
 0
20
 0
 0
40
 0
 0
20
 0
 0
 0
 0
40
 0
 0
20
  0
  0
  0
  0
160
 40
 40
Sample Time At Inorganic Total Glucose Protein
No Carbon Carbon mg/1 mg/1
mg/1 mg/1
A-I 12:40 0 27 90 0
B-I 12:40 0 26 88
C-I 12:40 0 27 91
D-I 12:45 5 26 91 73
E-I 12:45 5 26 90
P-I 12:45 5 27 91 20
G-l 12:45 5 26 88 110
A-0 1:25 45 22 137 164
B-0 1:25 45 22 140
C-0
D-0
E-0
P-0
0-0
A-l
B-l
C-l
D-l
1:27 47
1:30 50
1:30 50
1:32 52
1:32 52
2:30 110
2:32 112
2:35 115
2:36 116
16
22
17
19
20
19
16
20
120
144 167
120 62
130 140
116 110
118
122
123 153
Glutamic
Acid
mg/1
0
2
3
7
Oo
82
26
43
20
41
36
Starch Ammonia
A=520 X=680 mg/1
2 0
0 0
64 24

21 7
25
32 10 16
12
12
                              157

-------
Table No. 28.  con'.t
Sample
No '

B-l
F-l
G-l
A-2
B-2
C-2
D-2
E-2
F-2
0-2
A-3
B-3
.03 ,
D-3
E-3
F-3
G-3
A-4
B-4
C-4
D-4
E-4
F-4
G-4
A-5
B-5
05
D-5
E-5
F-5
G-5
Time At


2:38 118
2:40 120
2:42 122
3:35 175
3=37 177
3=39 179
3:40 180
3:42 182
3:42 182
3; 44 184
4:30 230
4:33 233
4:35 235
4:38 238
4:40 240
4:40 240
4:42 242
5:23 383
5:25 385
5:26 386
5:28 388
5:30 390
5:30 390
5:32 392
6:15 435
6:16 436
6*17 437
6:19 439
6:20 440
6:22 442
6:24 444
Inorganic
Carbon
mg/1
15
17
18
19
19
17
22
16
17
. 17
18
18
35
22
16
17
17
17
18
21
22
16
18
17
18
18
20
19
15
17
13
Total
Carbon
mg/1
54
93
104
99
114
134
120
54
72
93
73
109
111
118
55
62
90
64
109
103
114
55
63
86
64
85
72
87
50
59
62
Glucose Protein
mg/1


38

68




0

21




0

0




0

16




0

mg/1



123



153


110



130


95



135


88



115


73
Glutamic
Acid
mg/1

11
20


23
33

6



61
26

6



45
31

7
22


13
28

7

Starch
A ==520



5

18




1

0




0

7




0

6




0
X=680



1

4




0

3




0

3




0

2




0
Ammonia
mg/1

12
19
21.6





















11
14
17
14
10
13
20
Additional Feed Solutions added to each reactor
A-7
B-7
07
D-7
B-7
F-7
G-7
6:42 462
6:44 464
6:45 465
6:47 467
6:50 470
6:52 472
6:53 473
15
14
11
20
14
16
14
134
165
131
166
51
93
124
165




56




205


100


106
66

27
22

165




57

132




25







                             158

-------
Table No.
Sample Time At
No

A-8 8:58 598
B-8 8:59 599
C-8 9:00 600
D-8 9:01 601
E-8 9:02 602
G-8 9:04 604
A-g 9:45 645
B-9 9:45 645
C-9 9:46 646
D-9 9:46 646
E-9 9:47 647
G-9 9:47 647
8-12-70
A-10 10:151395
B-10 10:151395
C-10 10:153395
D-10 10:151395
E-10 10:151395
F-10 10:151395
G-10 10:15395
28 con't
Inorganic
Carbon
mg/1
12
12
18
19
16
13
11
10
19
19
13
13

14
13
14
17
18
12
16

Total Glucose
Carbon mg/1
mg/1
62 27
136
90
120
145
84
51 0
129
75
116
43
77

75
51
47
78
69
134
64

Protein
mg/1




160

81



155

75




105


75
                                              Glutamic    Starch    Ammonia
                                                Acid   A=520 X=680    mg/1
                                                mg/1

                                                         42     5
                                                85
                                                71

                                                37        00

                                                         19     5
                                                56
                                                59
                      solids were determined on the innoculum by
                     'and drying and showed 484 and 512 mg/1 respectively
on repeat tests.


                             159

-------
                             TABLE NO- 29
Effect of Milk Solids Concentration on Rate of Biological Degradation
in a Film Plow Reactor

Experiment No. 8-20-69, Plane Test #7, Film Flow Reactor Using Fixed
Slime Layer on Inclined Surface

Film flow reactor was acclimated for 3 weeks on dry milk solids feed
solution.  Growth was spotty, yellowish-beige in color and had a
gelatinous surface.  Slope of the surface was maintained at 0.0777
inches/24 inches.  Samples were collected from the mid section (4.4 in.
wide) for analysis.

Sample      Flow Rate     Carbohydrate    Organic Carbon    Protein
             ml/min       Concentration   Concentration     Concentration
                              mg/1           mg/1            mg/1
100 mg/1 feed solution         38             40              81
P-l           30                3             25              24
P-2           21                0             29              40
P-3            8.3              0             24              30
P-4            1.5              0             16               3
100 mg/1 feed solution         47             40              65
PL-1          17               34             27               5
PL-2           8.2             21             24               1
50 mg/1 feed solution          18             24              19
PL-3          43               13             18               5
PL-4          25               11             17               5
PL-5           8,1              4             16               5
PL-6           3.5              0             10               2
200 mg/1 feed solution                        89             139
Pl>7          42                              60              73
PL-8          26               75             68             132
PL-9           5.6                            62             117
PIXLO          2.4                            51             io4
500 mg/1 feed solution        162            220             308
PL-11         51              156            195             292
PL-12         18              132            180             243
PL-13          7.3             87            180             266
PL-14          2.4             56            120             139
                            160

-------
                             TABLE NO.  30
Effect of Milk Solids Concentration on Rate of Biological Degradation
in a Film Plow Reactor                               ;

Experiment No. 9-4-69,  Plane Test  #8, Film Flow Reactor Using Fixed
Slime Layer on Inclined Surface

This is an extension of Experiment #8-20-69, Test #7

Sample No     Flow Rate    Organic Carbon   Carbohydrate   Protein
                             mg/1         Concentration  Concentration
                                              mg/1          mg/1
Feed Solution (50mg/l)         28              11            40
P-l            T.Oml/lOmin      9               4            11
P-2            4.8ml/min       10               5     "       5
.P-3           15ml/min       ,   14              12      ••     10
P-4       ,    28ml/min          15              14            I8
200 mg/1 feed                 78              76       •'    133
P-5           26ml/min          63              41           102
P-6           12ml/min         54              10            65
P-7            3.2ml/min       39               5       •     87
P-8            3.5ml/10min     15               2            35
125 rag/1 feed                 50              33      '      88
p-9           27ml/min         44               1            70
125 mg/1 feed                 51              H        .    88
 p-10           7.6ml/10min     12               3            10
p-11           6.3ml/min       25              10            23
 P-12          13ml/min         31               8            32
 P-13         23ml/min         40               8            5«
                               161

-------
                             TABLE NO .  31
Effect of Laurie Acid Concentration and Mixed Feed Solutions on Rate
of Biological Degradation in a Film Flow Reactor

Experiment No. 3-17-70, Plane Test #9, Film Flow Reactor using Fixed
Slime Layer on Inclined Surface

Film flow reactor was acclimated to a 50 mg/1 lauric acid feed solution
for a period of several days.  The slope of the plane was maintained at
0.0782 inches per 24 inches.  Samples were collected from the center
portion 4.4 in. width and analyzed for organic carbon.  Initial part of
test used only lauric acid feed.  Mixed feed solutions were used at the
end of the test as shown.

Sample   Feed Rate   Organic Carbon   Glucose   Glutamic Acid
          ml/min         mg/1           mg/1       mg/1
100 mg/1 lauric acid      69
P-l      60ml/5min        52
P-2      12.1ml/min       67
P-3      25ml/min         64
100 mg/1 lauric acid      67
P-l      22.3ml/min       63
P-2      12ml/min         6l
P-3      12.Jjnl/5min      46
P-4      57ml/min         66
P-5      4l.0ml/min       65
P-6      21.0ml/5min      51
P-7      22.1ml/5min      54
50 mg/1 lauric acid       42
P-l      29ml/min         38
P-2      l8.1M/min       38
P-3      11.9ml/min       35
P-4      llml/min         33   •
P-5      10.1ml/5min      28
P-6      15.3ml/2min      33
P-7      11.0ml/5min      28
P-8      lOml/lOmin       21
25 mg/1 feed              21
P-l      47ml/min         18
P-2      34.2ml/min       17
P-3      44ml/2min        18
P-4      25.0ml/2min      17
P-5      37.0ml/6min      16
P-6      l6.4ml/5min      10
P-7      17.0ml/10min      7
100 mg/1 mixed feed (glucose,            71        130
  glutamic acid, Lauric acid)
                             162

-------
Table No. 31 con't
Sample

P-l
P-2
P-3
P-4
P-5
P-6
P-7
100 mg/1
P-l
P-2
P-3
P-4
P-5
P-6
P-7
P-8
P-9
Feed Rate Organic Carbon Glucose
ml/mln
6lml/min
47.0ml/min
38.0ml/mln
25.5ml/min
17.3ml/mln
20.0ml/2min
30.5ml/4min
mixed feed •
51.0ml/mln
43 . 8ml/mln
33.0ml/min
27 . Oml/mln
20.4ml/mln
I6.8ml/mln
17 . 2ml/2mln
19 . 6ml/4mln
5.8ml/20mln
mg/1
140
138
134
134
138
132
128
144
70
69
71
71
72
70
69
67
48
mg/1
72
72
71
72
76
72
75
75
75
74
75
76
75
73
72
69
45
Glutamlc Acid
mg/1
126
132
127
131
140
114
123
109
114
113
130
126
120
..121
117
97
24
                              163

-------
                             TABLE NO i 32
Effect.of Plow Rate on Biological Degradation of Mixed Feeds in a
Film Flow Reactor

Experiment No. 4-9-70, Plane,Test #10, Film Flow Reactor Using a
Fixed Slime Layer on an Inclined Surface

Film flow reactor was acclimated using mixed feed (glucose, glutamic
acid and lauric acid) for a period of 5 days. Flow  was interrupted
for one day on 4/5/70.  The slope of the plane was maintained at 0.0782
inches per 24 inches.  Samples were collected from the center section
(4.j4 in< wide) for analysis.

                                                            Glucose
                                                              mg/1
                                                               71
                                                               71
                                                               70
                                                               71
                                                               71
                                                               73
                                                               73
                                                               68
                                                               61

Continuation 4^10-70, Plane Test #11,  4/16/70
Feed Solution              124                                 69
P*a        49ml/min        120                                 89
P-2        35.9ml/min      n4                                 84
P-3        21.0ml/min      116                                 82
P-4        24;ML/min      108                                 79
P-5        36,9ml/2min     102                                 70
P-6        24.8ml/2min      98                                 64
P-7        l6.ML/3min      95                                 72
Sample Feed Rate Organic Carbon Glutamic Acid

Feed
P-l
P-2
P-3
P^4
P^5
P-6
P-7
P^-8

Solution
36ml/min
29.8ml/min
25.4ml/min
33.0ml/2min
l8.0ml/2min
I6ml/2.5min
9.0ml/3min
6-3nLL/7min
mg/1
136
134
132
132
130
128
120
106
96
mg/1
68
89
85
79
83
81
74
75
81
                            164

-------
                             TABLE NO. 33


Evaluation of Mixed Feed Solutions at Various Plow Rates in a
Film Reactor

Experiment No.  8-20-70, Plane Test #13, Film Flow Reactor Using A
Fixed Slime Layer on a Inclined Surface

The film flow reactor was  acclimated  to a mixed feed of glucose, glutamic
acid and lauric acid.  Ammonia addition was limited in order to'
avoid interference with amino acid test.  The slope of the plane was
maintained at 0.0782 inches per 24 inches,  Samples were collected from
the center reaction  (4.4 in. wide) for analysis.

Sample      Feed Rate    Organic  Carbon   Glucose   Glutamic Acid
             ml/min          mg/1          mg/1       mg/1
Feed Solution                 140            138        102
p-1           11.4           124            111        102
p-2            7-3           120              92         95
P-3            3.7            98              62     ,    98
p-4            8.8           120              75         90
 p-5           22.             130            116         93
 p-6           28.6           130              77         96
 P_7           40.             128            118         63
           Continuation - Plane Test  #14
 Feed Solution                 78              59         50
 P-1          100              71              58         45
 p-2           78              73             55         f
 P-3           60              76              54         87.5
 P-4           36           .74              54         47.5

 111           H              74             50         55
 P-7           20              76             54         56

 S3           ll              n             %

 as            u            11             i        %
                              165

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                                    TABLE NO.  34
      Evaluation of Starch, Protein and Laurie Acid Peed Mixtures in a
      Film Reactor

      Experiment No.  8-29-70, Plane Test #15, Film Flow Reactor Using a
      Fixed  Slime Layer on an Inclined Surface

      The  film flow reactor was, acclimated to a mixed feed of  100 mg/1
      starch and .protein and 50 mg/1 of lauric acid feeds.  The slope of
      the  plane was maintained at 0.0782 inches/24inches.  Samples were
      collected from the center reaction (4.4 in. wide) for analysis.

      Sample        Feed Rate    Starch, mg/1  Organic Carbon    Peptone
                      ml/min     X =520 X =680      mg/1            mg/1
      Feed Solution               104     99        54             118
      P-l              51          104     93        55             143
      P-2              33           76     72        53             118  •••
      P-3-             20.3         76     66        54             118
      P-4              13.           60     48        53             108
      P-5               8.           58     38        53             115
      P-6               5.           33     15        52             118
»U.S. GOVERNMENT PRINTING OFFICE: 1973  546-308/8 1-3
166

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SELECTED WA TER
RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
          w
    Biological Removal  of Colloidal Matter From Wastewater
           5.  i

           6.
           8.  f rformti.g 0rga,. '•• ation
   Au-thor(s)
    Maier, W. J.
 9.  Organization
    University of  Minnesota
    Minneapolis, Minnesota 55455
 12.  Sr i,tsor;> «: Organ; »
           i'j.  Project No.
           7 . CeinractlGtantNc.
               17030 DGQ

           $  Type fJRepo, t and
              Period Coveie ~^~
    Environmental Protection Agency report
    number,  EPA-R2-7 3-147, June  1973.
  If
    This research program was designed  to  provide a more basic understanding of the
    mechanism and rates of removal of organic materials from waste waters by
    biological processes.  Pure compound feed materials were used with the exception
    of a series of tests on sewage solids  obtained from the Minneapolis- St. Paul
    Sewage Treatment Plant by cent rifugat ion of primary effluent.  Two model reactor
    systems were used to measure rates  of  substrate removal.  The film flow reactor,
    characterized by a stationary biological slime layer, was used to study removal
    kinetics  under conditions where mass transfer may be a limiting factor.  A well
    mixed batch reactor was used to study  rates of removal under conditions where
    biological processes are rate controlling.  Rates of substrate degradation and
    carbon removal are reported for each of the pure compounds using acclimated
    innoculum.  Rate data from batch reactors are expressed in terms of microbial
    growth rate coefficients.  Rate data from the film flow reactor is reported as
    the quantity of substrate removed per  unit of slime surface per unit of time.
   J7a. .Descriptors
     *Biological Treatment, *Biodegradation-Rates, *Growth Rates-Microbial Population,
     *Mass Transfer-Membrane Processes-film flow reactor, Growth Rates, Enzymatic
     Degradation, Colloid Removal Colloid Degradation, Exoenzyme Activity


   17b. Identifiers
     Biological Removal, Biological Treatment, Organic Colloid Removal
   ; 7c  C 0 WR H Field & Group
           .' ty
                          "'/. $<••. v/if-y
                                                   Hi
                                            21,  No. of
Send To:

WATER RESOURCES SCIENTIFIC INFORMATION CENTER
US DEPARTMENT OF THE INTERIOR
WASHINGTON. D. C. 2O24O

                                      \  institution  University of Minnesota
VVRS1
       (HEX JUMP 1871,

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