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                                  DISCLAIMER


     The information in this document has been funded wholly or in part by the
United  States  Environmental  Protection  Agency  under  assistance  agreement
#CR811022 to  Lehigh  University.   It has been  subjected  to the Agency's  p«er
and  administrative  review and has  been approved  for publication  as an  EPA
document.  Mention of  trade  names or commercial products  does  not  constitute
endorsement or recommendation for use.
                                     ii

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

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

      One  of the major  procedures  for stabilization of  municipal wastewater
sludge is anaerobic digestion.   In this  report a comparison is provided between
operation  of the process  at mesophilic vs. thermophilic conditions.
                              E. Timothy Oppelt, Acting Director
                              Risk Reduction Engineering Laboratory
                                     lii

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                                  CONTENTS
Disclaimer 	 ii
Foreword 	 iii
Abstract	.'	 iv
Figures 	 vi
Tables  	 vii

     1.   Introduction  	  1
     2.   Conclusions   	  2
     3.   Recommendations  	  4
     4.   Experimental  Plan  	  5
     5.   Experimental  Procedures  	  6
               Apparatus	  6
               Operation  	  6
               Analysis of Sludge  and Gas  	 10
               Preliminary Studies  	 12
               Long Range  Operation and Results 	 13
     6.   Discussion of Results  	 28

References  	 30
Appendix-A  	 31

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                                FIGURES

Number                                                            Page

  1       Operational diagram of anaerobic digestion unit  	  7

  2       Details of construction of anaerobic digestion unit  ...  8

  3       Volatile acids concentration in mesophilic and
          thermophilic digesters vs. date 	 14

  4       Total  solids vs. date for raw, thermophilic and
          mesophilic sludges  	 18

  5       Volatile solids fraction for raw, mesophilic and
          thermophilic sludge vs. date 	 19

  6       Total  and soluble chemical oxygen demand (COD) in
          raw and digested sludges  	 20

  7       Ammonia concentration of raw, mesophilic, and
          thermophilic sludges vs. date 	 22

  8       Organic nitrogen concentration of raw, mesophilic,
          and thermophilic sludges vs. date 	 23

  9       Oil and grease concentrations in raw, mesophilic,
          and thermophilic sludges vs. date 	 24

 10       Total  carbohydrate concentration in raw, mesophilic,
          and thermophilic sludges vs. date 	 25

 11       Mean capillary suction time for mesophilic and
          thermophilic sludges vs. date 	 27
                                     vi

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                                   TABLES

Number

1         Summary of Performance of Mesophilic and Thermo-
          philic Digesters  	 28

A-1       Raw Sludge Data  	 31

A-2       Full  Strength Raw Sludge  	 32

A-3       Diluted Raw  Sludge Feed  	 33

A-4       pH-Alkalinity -  Volatile Acids  	 34

A-5       Speciated Acid  	 37

A- 6       Gas Production  	 40

A-7       Digested Sludge  Solids - Percent  	 47

A-8       Digested Sludge  - COD  	 49

A-9       Digested Sludge  - Nitrogen  	 50

A-10      Digested Sludge  - Oil and Grease  	 51

A-ll      Digested Sludge  - Carbohydrate  	 52

A-12      Digested Sludge  - Mean Capillary Suction Time 	 53

A-13      Capillary Suction Time Tests with Conditioners Added .. 55
                                    vii

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                                 SECTION  1

                                INTRODUCTION
     The purpose of  this  study  was to conduct a  comparative  evaluation of
the performance of anaerobic  digestion  systems  under different temperature
regimes.  The  temperature  regimes  chosen were those most  commonly  used in
field  installations (i.e.,  mesophilic 35°C and thermophilic 50-55°C).
Evaluation of performance is  in  terms of a number of parameters including:
stability of  operation,  degree  of waste  stabilization,  dewaterability of
digested sludge and odor.

     The  work  has been  divided  into  two  phases.    The  first phase  was
reported  on separately  and  dealt  with operation  of  anaerobic  digestion
systems under  temperature  transitions.   The  second  phase  which is  reported
on here, deals with  long term steady-state performance under mesophilic and
thermophilic conditions.   The basic question  to be  answered by Phase  II is
whether or  not thermophilic anaerobic  digestion is  superior  to mesophilic
anaerobic digestion.

     The  evaluation of  system performance  under  the   two  temperature
conditions was conducted in large laboratory  scale reactors (50 liter liquid
capacity) using municipal primary sludge from the Allentown,  PA Waste Water
Treatment Plant.   The  systems were monitored for the following parameters:
total  gas  and methane  production,  pH,   alkalinity,  total volatile  acids,
speciated volatile acids,  total  and soluble  COD,  ammonia-nitrogen,  organic
nitrogen, carbohydrate,  oil  and grease,  total  and  volatile   solids,  and
sludge dewaterability.   Data were collected at 25-day HRT and 15-day HRT.

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                                 SECTION  2

                                CONCLUSIONS

1)   Steady  state   operation  above  50°C  was  characterized  by  poor
     performance.    Volatile acids,  especially propionic  acid,  were  above
     1,000 mg/1.   Breakdown of various  sludge  components  was  less  than  under
     mesophilic conditions.

2)   Consequently,  long-term steady  state  data collection was  obtained at
     49.5°C in the thermophilic region.

3)   In terms of pH, alkalinity, volatile acids, and methane production  the
     long-term steady state performance at A9.5°C and 35°C was satisfactory
     at 25-day and 15-day HRT.

4)   Under all  conditions  the  performance  of the  mesophilic  system was
     slightly superior to the thermophilic system.

5)   At both detention times significantly higher breakdown of carbohydrate
     and oil  and grease were achieved in  the mesophilic unit.

6)   At  both detention  times   significantly  higher breakdown  of  organic
     nitrogen occurred under thermophilic conditions.

7)   At  both detention  times  slightly  higher  destruction  of   total  and
     volatile  solids and COD occurred under mesophilic conditions.

8)   The soluble COD of  the thermophilic sludge was always  at  least 1,000
     mg/1 higher than for the mesophilic  sludge.

9)   At both  detention times sludge dewaterability was significantly better,
     as measured by the CST test,  under   mesophilic  conditions.

10)  Sludge  dewaterability  for  both  temperature   systems   could  be
     significantly improved  by  conditioning  with  ferric chloride.   Higher
     doses were required for the thermophilic  sludge.

11)  Lime, both alone and with ferric chloride, had little  effect on sludge
     dewaterability.

12)  Performance of both  systems  was better,  in terms of  breakdown of raw
     sludge components, at 25-day detention  time.

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13)  Detention Time had little effect on sludge dewaterability.

14)  Thermophilic  sludge  odor  was more  disagreeable than  that  from
     mesophilic sludge even when volatile  acids were low.

15)  These  data  indicate  that  operation  of  anaerobic  digestion  at
     thermophilic  conditions  has  no  advantage over operation at mesophilic
     conditions.

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                                 SECTION 3

                              RECOMMENDATIONS
L)   The observation reported on here  of high propionic acid at temperatures
     above 50°C should be  investigated.   Pasteurization  can  be achieved by
     operation of anaerobic  systems at temperatures  above  50°C.   This will
     not be possible unless  the  systems  can operate  without  high propionic
     acid levels.   The reason for the high  propionic acid  levels should be
     ascertained so that  a remedy can  be applied.

2)   These studies should be repeated  with a sludge feed which is a mixture
     of primary and secondary sludge.

3)   These studies should be repeated  at lower detention times.

4)   Studies  of  the  operation of anaerobic  digestion  over  the  whole
     temperature range from  35°C  to  55°C should be  conducted to determine
     the true optimum temperature  for  operation of this process.

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                                 SECTION 4

                             EXPERIMENTAL PLAN
     The  basic  purpose  of  this  phase of  the  study was  to  compare  the
performance of anaerobic digestion processes at thermophilic and mesophilic
conditions.   Comparison was based on  parallel  steady-state operation over
periods  of several  months using a  feed  of   raw  primary  sludge  from  a
municipal  treatment  plant.    Evaluation of  performance was  based  on
measurement of  total gas production,  methane  production,  COD  destruction,
grease destruction,  carbohydrate  destruction,  organic nitrogen  destruction,
total  and  volatile  solids  destruction  and  sludge  dewaterability.   Two
periods  of steady-state operation were intensively monitored.   One period
lasted  almost six  months  during which  the  hydraulic  detention  time  was
maintained  at  25  days.   After a  short  transition period of two weeks  at a
20-day detention time, a second period of steady-state operation at a 15-day
hydraulic  detention was carried out for a two  and one-half month period.

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                                 SECTION 5

                          EXPERIMENTAL PROCEDURES
APPARATUS

     The anaerobic reactors used  In  this  study are illustrated in Figures 1
and  2.    These  were  constructed  of  lucite  and  were  rectangular  in cross
section.  Interior bottom panels sloped from the vertical sides to the split
pipe  outlet which  in turn  was centered  in the  base  of  the unit.   This
insured that there were  no  dead spaces near the bottom of  the unit.   Total
volume of each reactor was approximately 75 liters, with 50 liters of liquid
maintained  in  the unit  at a  detention time  of  25 days and  45  liters  of
liquid  maintained during the  period  when the  detention  time  was  15 days.
Each  unit was mixed  by gas  recirculation using  a  diaphram   type  gas  pump
rated  at  9.5 liters  per minute  with a maximum  pressure  of  18  psi.   The
operation of the  mixing pumps was not  continuous  but  rather was  controlled
by a timer  set to turn the pumps on 6 minutes each one-half hour.

     An alternate mixing technique  which  could be used was a  hand operated
diaphram pump which could circulate the liquid sludge from the  bottom of the
unit  to  the top  through  an  external pipe.  Each stroke  of this  hand  pump
could displace approximately 300 ml of liquid sludge.

     The  inlet  and outlet  lines  for the   feed  and digested sludge were  1"
schedule  80 PVC  pipe.   Full flow ball values of  the same material and  size
were used to control  flow in and out of the unit.

     Gas  measurement  was made  with  a Wet  Tip Gas Meter (Wet Tip  Meter  Co.,
Wayne,  PA.) which  functions   on  the  liquid   displacement  tipping  bucket
principle.  These meters were  calibrated against a Wet Test Meter at the gas
flow rate anticipated in the  anaerobic  reactors  (1-5  liters per hour).   The
wet  tip type meter provides a  water  seal on  the  gas  outlet  line with a  back
pressure  equal to the water depth in the meter (5 1/2 inches).
OPERATION

     Raw primary  sludge was periodically collected from the  Allentown,  PA.
Sewage Treatment  Plant.  This is a typical municipal treatment plant serving
a  large metropolitan  area.    It  has  a  reasonable   mix  of  domestic  and
industrial  wastes (plating, brewery, meat  packing,  food  processing,  truck
assembly).    The  sludges  at this  plant  -are separated  so  that  the  primary
sludge contains little  or  no secondary  sludge.   Sludge is digested  at this

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Figure  1.   Operational  diagram of  anaerobic  digestion unit,
         gas  pathway

         sludge  path-
         way
electrical  gas
recirculating
      pump
                             r
                               water trap
                                     1"  ID rubber tubing .
                           sludge feeding
                               funnel
                                   \
  to
atmospheric
 vent
        J" PVC ball  valves

          sludge return  tube
   3/4"  ID
                                                  wet tip gas meter

                                                   gas sampling port




                                                   plug
                                              1" PVC ball  valves
                  manual
                  sludge
                 recirculation
               Xj  pump
      1" PVC ball  valve
                                                       PVC pipe
                                                          sludge drain and
                                                              alternate
                                                               sampling
                                                               port
                     sludge collector tube
                                         gas trap

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Figure 2.  Details of. construction of anaerobic digestion unit.
   1  1/4  X  3/16"/T) I
   machine  screws///
 &  flat washers ////

              ill
    36 1/2"
1" ID PVC sludge feeding
tube projecting through
unit top
_1" ID PVC gas redrculating
tubes projecting through
unit top
  unit top of 9/16" thick
plexiglas

  7/8" wide square rubber
gasket, 1/8" thick

   upper frame members of
3/4 X 3/4" plexiglas
                                                1" ID PVC sludge return tube
                                                projecting through unit sides

                                               i" ID PVC gas return tube pro-
                                               jecting through unit top

                                                     corner frame posts of
                                                    X 1/2" plexiglas
                                                 unit sides of 7/16" plexiglas
                                                  ''vee" bottom of 7/16" plexi-
                                                                         glas

                                            Unsealed airspace beneath vee

                                                 1" ID sludge collection tube
                                              i.     projecting through unit
                                             2 1/2"                     sides
                                              r

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plant in a mesophilic  digester  which usually operates at a 20-day detention
time.  In order to  control  odors,  raw primary sludge is rapidly pumped from
the  primary  clarifiers,  thus  thickening  does not  usually  occur  in  the
primaries.  Sludge  was collected as  it was being pumped from the primary to
the sludge handling area.

     The sludge collected was transported  to Lehigh University Environmental
Studies Center  and  kept  under refrigeration at 4°C until  used.   Sludge was
usually collected once per  week.   Upon being brought to the laboratory the
sludge was sampled  for total and volatile  solids analysis.  These data were
used  to  determine  if  the sludge had to be diluted prior  to  use.   Dilution
was  with  Bethlehem, PA  tap water.   It was decided  early in the  study to
maintain  a constant total  solids  concentration in the  feed.   The original
target was 4%,  but after one  month  of sludge  feed to  the units this value
was  changed  to  3.5%.   The  latter  was chosen when experience indicated that
sludge obtained from  this plant often was  in the range 3.5% to 4.0%  solids.
The  sludge was  relatively weak because as  indicated above  thickening  was not
conducted in the primary  clarifier.   Each  sludge  batch was kept  in a 10-
gallon plastic  container under refrigeration.

      Two  anaerobic reactors  described previously were used  in  this study.
Each was  kept in a  walk-in  temperature-controlled room.  The gas meters were
also housed  in  the respective rooms.  Temperature control was achieved with
 the  use  of  a   thermostat  and  an  electric space  heater.   A  large  air
circulation  fan was run continuously in each incubator to maintain  uniform
 temperature  distribution.   Each thermostat could keep the  air temperature at
+1°C from the set point.  The  temperature  in each unit, however,  was  + 0.1°C
from the  set point because the large mass of water  in  each reactor evened
out  the air  temperature  swings.

      Each reactor  received identical  treatment except  for the temperature.
Feed of raw  sludge  and withdrawal  of digested sludge was conducted once per
day.  The procedure was:

1)    Several  hours  prior to the feeding time the proper quantity of sludge
      was  taken from the 10-gallon reservoir  in the  refrigerator and placed
      in  the  incubation  room  to  warm it  prior  to  feeding:    Dilution  if
      necessary  took place  at  this time using Bethlehem tapwater maintained
      in  the  incubator  room.

2)    At  the  appointed  time  the  gas meter reading was  recorded.

 3)    The  valve  from the reactor to  the gas meter was closed.

4)    The   hand   pump  was   used  for  a   minute   to   circulate   sludge.
      Simultaneously the  gas recirculation  pump  was activated.

5)    Sludge  was withdrawn  through the bottom outlet line into a bucket, and
      then was put back into the unit through the feed reservoir in the top.

6)    This procedure in  (5) was repeated  several  times until the  layer of
      solids  and  foam  at the top  of the  reactor was  completely broken up.


                                      9

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     The  hand pumping and  gas  reclrculation was not  able  to break up  this
     Layer even though the main body  of sludge was, by visual  observation,
     well mixed.   Only the cascade of  sludge from the inlet line was  able to
     disperse,  temporarily, this layer.  The level  of liquid in the  reactor
     was  checked  against  a calibrated  scale on the reactor  side.   If  the
     level was  low (due  to  evaporation) make  up  Bethlehem  tap water  was
     added.

7)   After the layer  at  the  top of the  liquid  was  dispersed and the water
     level adjusted, the daily sample  was withdrawn.

8)   The feed was then placed in the feed funnel  at the top  of  the  reactor,
     and entered  the  unit  when  the  1"  feed  valve was opened.   In step  3 it
     had been  indicated  that the gas  outlet valve  was  closed.   This valve
     was kept  closed  throughout the procedure in steps 3  through 8.   Thus
     when  the  daily  withdrawal  was made in  step  7  the  system was  placed
     under  a vacuum.    This  procedure  facilitated  the feeding of  the  raw
     sludge  slurry  in step 8, as  the vacuum helped  pull the  sludge  into the
     reactor.

9)   After  feeding, the valve  in  the  gas outlet  line was  opened to  restore
     gas flow  to  the  gas meter.
ANALYSIS OF SLUDGE AND GAS

     Periodically  the raw  sludge,  digested  sludge  and  gas  produced  were
analysed for  a variety  of  parameters.   The  procedures  used are  presented
below:

Gas Measurement and Analysis

     Gas volume production was measured with a "Wet Tip Gas  Meter".   In this
type of meter the gas enters a  submerged housing and displaces water.   When
sufficient water is displaced a  counterweight causes the housing to  tip and
this  event  is recorded  on an  electronic  counter.   The  housing  is  double
sided and piped so that  after tipping, gas  is directed to the now  submerged
side and the  process  is  repeated.   Each count represents a standard volume
which  is  a  function of  the  adjustable   counter  weight  position.    The
manufacturer  claims  accuracy  at 97%  to  99% up  to 500  ml/minute.    In  this
study the meters were calibrated periodically against  a Wet Test Meter.  A
problem  encountered  was  that  the  counterweight  gradually  changed  due  to
accumulation  of  sediment  in  the water.    This  was generated  by  reaction
between the digester  gas and the water  in  the meter.   Another was the  need
to periodically add  make up water  to  the  meter to counteract  evaporation.
Except for several periods when  problems such as counterfailure and  leakage
in  the  inlet  line   were encountered  the  gas  volume measurement  was
satisfactory.

     Analysis of the  gas  for methane  and carbon dioxide was conducted using
a  Fisher  Gas  Partitioner (1)  which  operates on  the  thermal  conductivity
principle.    Gas  samples were  taken from  the  head  space  of  the  reactor


                                     10

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through a gas sampling port using 100 ml capacity glass bulbs connected to a
reservoir  bottle  filled with  acid-salt  solution.    The  partitioner  was
calibrated before  each  use  with 100% methane, 100% carbon dioxide  and 100%
nitrogen.   These  produced  peak  heights  on the  apparatus   recorder  as  a
function of  signal attenuation setting.  The samples  were  run at  the same
attenuation setting as were used for the calibration.   Volumetric percentage
of each  gas  in the sample  was determined by ratio of peak height of each
component  to  that produced by  the  100%  standard.    This  procedure  is
considered accurate to  about 1%.

EH

     pH  was  determined using  an  electronic pH  meter,  Fisher  Model  830
Acumet.   Temperature compensation  was used  with  a glass  electrode.    The
procedures in  "Standard Methods" (2) were followed.

Alkalinity

     Alkalinity  was  determined  by   the  titrametric  procedure in  "Standard
Methods"  (2).   One hundred milliliter samples of  sludge were  titrated with
IN sulfuric_acid to pH  4.2.

Volatile Acids

     Total volatile acids were  determined  by the direct distillation method
presented  in "Standard  Methods" (2).   Volatile acids were  speciated  on  a
Dionex Ion  Chromatograph  using specific  conductance  as  the  detection
technique.   Separation of   formic,   acetic,  propionic, butyric  and lactic
acids  (non-volatile)  was accomplished  on a Dionex  ASI  anion  column  preceded
by an  anion guard column.   A  Model 14 Ion Chromatograph was modified  to
allow  high  pressure  operation necessary  to  speciate  volatile acids.
Calibration  was  by standards of the pure  acids at 10, 100  and 1000  mg/1.
Sample analysis was by  the  peak height  ratio  method.   Prior  to injection  in
the  Ion Chromatograph,  the sludge   sample  was  filtered  through a  0.45  u
membrane filter and the  pH was adjusted to  pH 4.3 with  nitric acid.

Total and Volatile Solids

     The procedures used were in accordance with "Standard Methods"(2).  Raw
sludge analyses were performed in triplicate; for digested sludge  duplicates
we're used".  Results were almost always  +2% ~of~l:he  average.   The sludge "was
ground in a Waring blender prior to  analysis.

Ammonia Nitrogen and TKN

     Analysis  was  in accordance with  the  Kjeldahl (Macro)  procedures  in
"Standard Methods"(2).   Distillate was collected in boric acid and  titrated
with N/50 sulfuric acid.  Duplicates were run on all samples  and reported  as
the average.   All sludge was ground  in a Waring  blender prior to analysis.

                                     11

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Grease and Oil

     Determination was by  the Soxhlet Extraction method given in  "Standard
Methods"(2).  Only single samples were run.

Chemical Oxygen Demand

     COD  was  determined  by  the  Open  Reflux  Method given  in  "Standard
Methods"  (2).   Soluble  COD  was  run  on sludge  filtered  through  0.45  u
membrane  filters.    The  sludge  was  ground  in  a Waring  blender  prior  to
analysis.

Carbohydrate

      Total  and soluble carbohydrate was  determined by  the  method  of Dubois
 et al.  (3), as modified by Herbert et al.(4) and Kampmeier et al.  (5).   It
 is a colorimetric  procedure in which  phenol and hot sulfuric acid react with
 sugars  to form an orange chromophore.  The color is read  in  the  range 480-
 450 run.   Standards are  prepared  using  glucose.   All sludges were  ground
 prior to use in a Waring blender and soluble carbohydrate was determined on
 the filtrate from a 0.45  u membrane filter.

 Capillary Suction Time (GST)

      Sludge  dewaterability  was  determined by  the   CST  test using  the
 apparatus produced  by Triton Electronics LTD.  of England.   Unconditioned
 sludge was  measured using the 3/4"  diameter  cup.   Conditioned sludge  was
 measured using the  3/8" diameter cup.  The results reported  are  average of
 triplicates.
 PRELIMINARY STUDIES

      During  the  summer of 1986  the  two reactor systems  were  constructed,
 leaks  corrected,  and  seeded with  digested  sludge  from  the  Allentown
 mesophilic  digester.    In addition,   several  gallons  of the  thermophilic
 -sludge  saved from  Phase  I  (under  refrigeration)  was   added  to  the
 thermophilic  digester.    Initially the  digesters were  fed   the  artificial
 substrate  used in  Phase  I.    The mesophilic  unit  was  set at  35°C,  the
 thermophilic unit in the range of 53  to 55°C.   For several weeks  biological
 action  was  satisfactory  in   both  units but  then  gas  production  started
 dropping in  the thermophilic unit and volatile acids increased. Addition of
 more sludge  from  the store saved  from  Phase  I  temporarily  alleviated  the
 problem,  but  as   the  seed  was  washed  out  by successive  feedings  poor
 performance  returned.   In  September  thermophilic digested  sludge  was
 obtained  from  the Rockaway  Plant  in  New  York  City  and  added  to  the
 thermophilic unit.  The feed was changed to a mixture  of glucose and whole
 milk as  it  became  difficult  to  obtain  the  original version of Carnation
 Instant Breakfast.  The temperature was  reduced  to the range 50°C to 52°C as
 the New York  City  sludge  digester was being operated at approximately 50°C.
 Again after several weeks poor performance  set in.   Near the end of October
 a dose of  25  mg/1  of  yeast extract was  added  to the thermophilic digester.


                                      12

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In less than  two  days gas production markedly  increased and volatile acids
returned  to  normal.    It should  be noted  here  that  the  high  levels  of
volatile  acids during  this  phase  were almost  completely  propionic acid.
Direct additions of acetic and butyric acid to the reactor resulted in rapid
reduction of  these acids  in one  day.  Propionic  acid on the other had never
declined until yeast  extract was added.

     During   this  period  of  several  months   the  mesophilic  unit  always
exhibited  good performance  even  without the  addition  of  yeast extract.
Eventually  yeast  extract  was  added  to  both units  in  order to  keep their
operation,  except for  temperature,  identical.   For a  period  of one month
successful  operation  was  achieved in both reactors  using a feed of  glucose
and  whole  milk.    Measurement  of  the methane  production  indicated  that
virtually  all of  the  organics  being  fed were  converted  to  methane.
Consequently, at  the  end of November  the feed  was changed  to raw  primary
sludge  and the operation at a  25-day  detention time begun.   As  indicated
above,  25 mg/1 of yeast extract  (Difco) was  added  to the  feed each  day.
 LONG RANGE OPERATION AND RESULTS

      For a six-month period the reactors  were  operated at a 25-day detention
 time.   No change in  the  operation  of the mesophilic digester was necessary
 during that period.  However,  a  significant change  in  the  operation of the
 thermophilic digester was  made after 3  1/2 months  of  operation.   At that
 time the temperature was reduced from slightly above 50°C to slightly below
 50°C.   This was done in  order  to improve the  operation of the thermophilic
 system.   Figure 3  illustrates  the volatile acids levels  in  both digesters
 starting in  the beginning  of  December,   1986.   It  can be  seen  that  the
 volatile  acid  level in  the  mesophilic  digester   was  consistently  low.
 However,  the  level  in  the thermophilic  system  gradually  increased  and
 reached a level of 1500  mg/1 by the middle of February,  1987.  Reference to
 Table A-5 which gives information on the volatile acid speciation indicates
 that approximately  90%  of  the volatile  acids present in  the  thermophilic
 unit was propionic  acid.  Gas production  and COD  data were in accordance
 with the high levels of  volatile  acids  in the  thermophilic unit;  that is gas
 production  was  lower  and  COD  was  higher  in  the thermophilic  vs.  the
 mesophilic unit (See Tables 6 and 8).

      During the last week  in February, the heater  in the thermophilic room
 failed.    Over night the temperature dropped  to  approximately  40°C.   The
 heater was repaired and  by the  next day the temperature had returned to its
 usual value of 51°C.  Surprisingly, during the day when the temperature was
 low, a much  larger  quantity of gas was  evolved from the  thermophilic unit
 than usual  and  volatile acids showed  a  significant drop.   By  the  end of
 February,  the volatile  acids in the thermophilic unit were  almost as low as
 those in the mesophilic  unit.   In addition, it was  noted that the propionic
 acid comprised only 20%  of the  volatile acids  in the  thermophilic unit.  The
 data for March  indicates that  a slow  rise in volatile acids  at about  the
 same rate  as had  occurred in December  and January.   The  propionic  acid
 fraction of  the  total  volatile  acids  rose  to  70%.   At  this point  the
 temperature set point  of  the  thermophilic room  was reduced  to  keep  the

                                     13

-------
   16
Figure 3.   Volatile  acids  concentration in  mesophilic  and  thermophilic  digesters  versus  date.
           Mesophilic  digester temperature  was  35°C,  thermophilic  temperature  exceeded 50°C
           except as noted.   Hydraulic  detention  tim?  in both cases was  25  days.
3
-C
   14
   12
   10
•2   8

-------
temperature in the  unit  between 49°C and 50°C.   Volatile acids,  especially
the propionic acid,  rapidly  fell to levels which approximated  those in the
mesophilic  unit.    Based  on  this  evidence,  the  temperature  in  the
thermophilic unit was maintained at 49.5°C for the remainder of this study.

     The operation  at 25-day detention time was maintained through April and
May.    At   the  end  of  May  the  detention time  was  reduced  to  20  days.
Maintenance  of  operation  at  this detention  time was intended  for  several
more months.  However,  after two weeks thn detention  time  was  converted to
15  days which was maintained for  the next  2 1/2  months.   This latter change
was made  because  it was felt  that  a  15-day detention time  was  more
representative of field  conditions.

     Once  the temperature  in  the  thermophilic  unit was reduced  to 49.5°C
essentially trouble free operation was maintained in  both  units.   The data
which  are  presented here are basically broken into 4 periods of operation:
 Time Period
 December 1986 -  March 1987
 April   May 1987
 First-half June  1987
 Last-half June   August 1987

 Raw Sludge Characteristics
Detention Time
       Temperature

Thermophilic   Mesophilic
     25 days
     25 days
     20 days
     15 day
    50.5
    49.5
    49.5
    49.5
35.0
35.0
35.0
35.0
      The characteristics  of the raw sludge fed to the digesters during this
 study are presented  in Tables A-l, A-2,  and  A-3.   Table A-l  presents  the
 data on  raw sludge  solids  (total  and volatile).   Also presented  are  the
 dates when the sludge was procured  from the Allentown, PA. STP and the dates
 it was fed  to  the  anaerobic reactors.   Table A-2 presents  the  analyses  of
 the  full  strength  sludge  for  various  parameters and  Table A-3  gives  the
 values of these parameters after dilution of  the raw  sludge.   As indicated
 previously dilution was used to reduce the total solids  in  the  actual feed
 to 3.5%.   All analyses were conducted on the  full strength feed rather than
 the diluted material.  It  was thought  that more accurate results  would  be
 obtained using  this  technique, as  the  inaccuracy  in making  dilutions  and
 sampling small volumes would be avoided.   All  samples of raw sludge used for
 analysis were ground in a Waring blender prior to the start of the analyses.
 It should be noted  that  batches of raw sludge obtained on  a  specific date
 were fed to  the  systems  during different consecutive periods and  that  the
 sludge characteristics changed significantly from  one  period  to  another.
 For example, the sludge  obtained on 4/27/87 was  used  for three consecutive
 periods  4/28-5/4, 5/5-5/11,  and 5/12-5/18.   These  three  periods represent
 separate fillings  of the  10-gallon  storage   reservoir  from  individual  5-
 gallon buckets used  to transport sludge  from  the treatment  plant.   It  was
 found the the sludge  although collected  at the  same  time was occasionally
 significantly different in each of  the 5-gal.  buckets.  Thus the differences
 between  consecutive 10-gal. units  of  sludge were not  mainly due  to
 deterioration of the  sludge in storage.   The  results given in Table A-l,  A-
                                     15

-------
2, and A-3  indicate little  difference  in this sludge  from that considered
typical raw sludge.  The major differences were a consistently high volatile
fraction of solids  (generally >80%),  and high grease and  oil content.  The
latter is probably  responsible for the high volatile solids content.

pH. Alkalinity and  Volatile  Acids - Digested Sludge

     Table  A-4  presents pH,  alkalinity,  and total volatile  acids  data for
the  effluent  from  the two  systems  throughout the study.    Except  for the
period  of  high  volatile  acids  discussed previously  volatile  acids were
usually  quite low  approximately 100-250  mg/1.   For a few  days  after the
change from a 20-day detention time to a  15-day detention  time, the volatile
acids in  the  thermophilic  unit increased  slightly, but  soon they  fell  to the
usual levels.  With respect  to volatile acid speciation as shown  in Table A-
5,  there  was no specific  trend  except  for that discussed earlier  when thp
temperature was  above  50°C.   Once the temperature was reduced to below 50°C
the  predominant  volatile acid in the thermophilic unit was acetic acid. In
the  mesophilic  unit sometimes acetic was dominant,  sometimes propionic was
dominant  and  at  other  times  both were approximately equal.

      The  pH and alkalinity  data indicate  that both were consistently  higher
 in the thermophilic  unit,  although  the  magnitude of  the differences were
 small.   These data reflect the higher breakdown of organic nitrogen observed
 in the  thermophilic  unit.    Breakdown   of  organic  nitrogen leads  to the
 formation  of  ammonium  bicarbonate which titrates  as  alkalinity.    This
 compound serves  as the main buffer  in anaerobic treatment  systems.  Table A-
 9 which  presents  data  on  the ammonia-N  concentration in these  units and
Table A-4   illustrate the correlation between these two parameters.   The pH
 and   alkalinity  were  both  in the  normal range  of  these  parameters  for
 anaerobic digestion systems,

Gas  Production

      Gas  production data are  presented in Table A-6.   The methane fraction
was  similar in both units.   It ranged from 57.5%  to  64.5% with a mean close
 to 60%.    Daily gas  production was relatively  constant;  changing  only in
 response  to changes in strength  of  the feed.   These data have been converted
 to volumes  of  gas at  0°C  and  1  atmosphere  pressure but  have not been
 converted to a  dry gas basis.   Assuming the  gas was  saturated  with water
vapor at the  temperature  of  the reactor and  that the  mixture  of methane,
 carbon  dioxide  and water vapor acts as an ideal  gas,  the correction  factor
 to  be  applied  to  the data  in A-6 to convert  to dry gas basis  is 0.8813 at
49.5°C  and 0.9445  at  35°C.

Total and Volatile Solids  -  Digested Sludge

      Data  on  total and volatile solids are  given  in Table  A-7  and are
plotted  along with the raw sludge data on solids in Figures 4 and 5.   It can
be seen that total and  volatile solids  were almost always higher  in the
 thermophilic  unit  than the mesophilic  unit.   The  differences were most
pronounced during  the  period when the thermophilic unit  was at a  temperature
above 50°C.  But,  during  the latter part of May and August  (the end of

                                     16

-------
each steady-state period), solids levels in both units were almost the same.
In July total  solids  levels  in both units suddenly peaked  at  2.2% to 2.35%
and then  dropped back to the  usual  levels  near 2.0%.   this  coincided with
increases in raw and  digested sludge organic nitrogen,  and oil and grease.
Overall volatile solids  destruction was higher in  the  mesophilic unit than
the thermophilic unit.

COD

     Chemical  oxygen  demand,  total and  soluble, in each reactor is presented
in  Table  A-8.    These data along with  the  raw sludge COD  are presented in
Figure  6.   Prior to lowering the  thermophilic temperature below 50°C the COD
of  the  thermophilic unit was consistently higher than that  of  the mesophilic
unit.   During  the  April-May  period  (25-day  detention  time after thermophilic
temperature was lowered) the COD  of  both units was similar.  After reduction
of  the  detention time  the  COD  of  the  thermophilic sludge  was initially
higher  than that  of   the  mesophilic sludge.   Much  of  this  difference  was
eliminated by  the end of the 15-day  detention time operation.

      The  soluble COD  data indicate that the thermophilic unit had a soluble
COD about  1400  to   1700  mg/1 higher  than in  the  mesophilic  unit.    The
difference was greater in the period when the thermophilic  unit was operated
at  temperatures above 50°C.    Indeed,  the  first period of  lower  temperature
operation when the space heater failed can be  seen on the  soluble COD plot;
as  a  significant drop  in  soluble  COD  in the  latter  part  of February.
However,  even  under  the  best of thermophilic operation a definite difference
 in  soluble COD was observed.

Nitrogen

      Nitrogen  analyses  of the reactor contents as well as the  raw  sludge
feed are presented in Table  A-9  and Figures 7  and 8.   It  can be seen that
 the ammonia-N  was always higher and  the organic nitrogen was always lower in
the thermophilic unit.  Since the TKN  of  both  units was the same these data
indicate   superior   organic  nitrogen conversion  to  ammonia-N  in  the
thermophilic unit.   The  difference  was higher  at 25-day detention time than
at  15-day  detention  time.   The  quantitative differences will be discussed
later  in this  report. As  indicated  previously because  of  the  higher  degree
of  conversion  of organic  nitrogen  to  ammonia-N the  pH  and alkalinity were
always  higher  in the  thermophilic than  in the mesophilic unit.

Oil and Grease

      Table A-10  and  Figure  9  presents the oil  and  grease data collected
during  this study.  It can be seen  that the reduction of oil and grease  was
higher  in  the mesophilic  unit than in   the  thermophilic  unit.   This
difference was especially pronounced when the thermophilic  unit was operated
above  50°C because volatile  acids  are measured as grease  and oil in this
particular  analytical  test.     There  seems  to  be  little  change  in  the
difference between the units which could be  ascribed  to the reduction of the
detention  time  to 15 days.    These data will  be reviewed  later in this
report.
                                     17

-------
cc
                              Figure 4.  Total  solids  versus  date for raw, thermophi 1 ic, and mesoph.ilic sludges.



                            4.2




                            4.0
                          OJ
                          3
                          -N.
                          •M

                          •§,3.4


                          OJ
                          3


                          % T 7
                          rt3 J . c



                          C
                          O


                          « 3.0
                          0)
                          o


                          S  2.3
                            2.1



                            1.9




                            1.7



                            1.5




                            1.3
                                    Dec
                            «raw sludqe
                             mesophilic sludge
                            •thermophilic sludge
                                                  /
                                                /   ••••«.
Jan
Feb
Mar      Apr

      Date
May
Jun
Jul
Aug

-------
     Figure 5.   Volatile solids fraction for raw, mesophilic and thermophi1ic sludges versus date.
   86







   84







^ 82

•o



o

1/1 80





OJ
o.


10 74
- 72

 o
 to

 
-------
                         Fiqure 6.  Total and soluble chemical oxyaen demand (COD) in raw and digested sludges.
NJ
o '
                          28





                          24
                        •2-0
o
o
LJ
                          16
                                  f.
                                 t\
                                                               Raw sludae: Total COD
                                                                                                                ,60
                                                                                                                150  g

                                                                                                                    o
                                                                                                                30
                                       Digested sludge: Total COD
                                                                           A.
                                    A

                                   ' N
..      \  ;,

'••• .-••-. \  if
  V  ••\if
       V
	mesophll1c  sludge

— —-thermophillc  sludge
                                                               Digested sludge: Soluble COD
                                                     \
                                                      \     ,'   \
                                                       \   I     \

                                                        \ I

                                                         V
                                                          	mesophlUc sludge

                                                          •-	'thermophlHc sludge
                                                                                           o
                                                                                           o
                                                                                           o
                                                     /  V

                                Dec      Jan      Feb       Mar      Apr     May       Jun      Jul      Aug


                                                                 Date

-------
     Sludge carbohydrate measurements were only conducted during the 15-day
detention  time  operation because the  method of analysis  utilized  was not
found until late in the Spring,  1987.  These data are presented in Table A-
11 and Figure 10.  Total carbohydrate reduction was higher  in the mesophilic
unit than in the thermophilic unit.   The difference ranged from 500 mg/1 to
1200 mg/1.  Soluble COD was also lower in the mesophilic averaging about 50
mg/1 less than in the thermophilic unit.

Sludge Dewaterability

     Throughout  most  of  the  study  measurements  were  made  on  the
dewaterability  of the  effluent from  each  unit.   Preliminary  tests  were
performed using three  methods  of dewatering.  One technique was  the
Capillary  Suction Time Test (CST).  another was  the  Buchner  Funnel Filtration
Test,  the  third  was  a batch centrifugation test developed by Vesiland (6).
It was found that the latter two tests were very difficult  to run unless the
sludge  was  conditioned  with a  coagulant.    The  CST  test,  however,  gave
reasonable measurements with and without  the addition of coagulants.  Thus,
the  CST  test was used to characterize the difference  between both types of
sludge.   Table A-12  and Figure 11  present  data  on the  CST measurement for
the  sludges  throughout the  steady-state portion  of  this  test.    The
measurements in  March were  made at  room  temperature but the temperature was
not  recorded.   Starting in the beginning  of May,  temperature  was recorded
and  eventually  the  temperature  at  which the test  was  conducted  was
standardized  at  25°C.    The  results  substantially  indicate  that  the
thermophilic sludge was  more difficult to dewater in an unconditioned state
than the  mesophilic  sludge.   Visual  observation of  the  sludge  clearly
indicated  better  separation  under   gravity  conditions  for  the  mesophilic
sludge.   In addition, the  sludge  supernatant  was visibly dirtier  for the
thermophilic  sludge.    This  indicates  that  the  size  of digested  sludge
particles  in  the  thermophilic  sludge was  smaller  than in  the mesophilic
sludge.    When  the  sludge  was   subjected  to  centrifugation without
conditioners present,  the  thermophilic centrate  was much  dirtier  than that
from the mesophilic sludge, although the  depth  of the solids pool was almost
the  same for both sludges.

     On  July  5 CST measurements were made at 25°C, A9.5°C am'  35°C.   This
was  achieved by bringing the  CST apparatus  into the incubation rooms.   As
would be expected, the CST  was lower at  the  higher temperatures.  The ratio
of CST at the  higher  temperature  to the  reference temperature  (25°C)  was
300/377  for the  mesophilic  and 415/534 for  the thermophilic.   The ratio for
the  mesophilic  sludge is that expected based on the viscosity  of water at
35°C and 25°C.   However,  the  ratio for  the thermophilic  sludge  is  not in
accordance with  the viscosity ratio of water at 49°C vs. 25°C.

     In  addition to  the  unconditioned  tests some tests were  conducted in
which  sludge was conditioned with  ferric chloride  and/or  lime.   These data
are  presented  in  Table  A-13.    It  can  be  seen  that  ferric chloride
conditioning had a significant affect on  the  CST values  of both sludges.
                                     21

-------
                      Figure 7.  Ammonia  concentration of raw,  mesophilic, and thertnophi 1 ic  sludges  versus date.
ro
t-o
    200


    150'



    100


     50


      0


   1000
c
OJ

§   900
<_>
                     
-------
                         Figure 8.  Organic nitrogen concentration of raw, mesophilic, and  thermophilic sludges versus date.
N>
U>
                        2000
                        1600
                     =r 1200
                      c
                      o
 800




1200


1000


 800


 £00


 400


 200
                             - \
                                    \/
                                    V
                                             raw sludge
                                            tinesophil ic sludge
                                            • thermophil ic sludge


                               Dec
Jan
                                                  Feb
                  Mar
                                                                _l_
   Aor
Date
                                                                             May
                                             Jun
                                                                      Jul
Aug

-------
      Figure 9.   Oil  and grease concentrations in raw,  mesophilic,  and  thermophilic
                 sludges versus date.
N) .
-C-
      7.6




    "^6.8


    c
    o

    Se.o
C
OJ
o


§4.4

Ol
t/1
ra
QJ

O>3.6

TD
c
fO
    52.8
      2.0
      1.2

                       /     \  /  \

                            v
                                                        'raw  sludge
                                                        -mesophilic  sludge
                                                   •	• thermophilic  sludge
X-'i
                                                               rv
                                                               :• \ I  \
                                                                    *
                                        _L
             Dec    Jan     Feb     Mar    Apr     May   Jun      Jul    Aug

                                        Date

-------
Figure 10.  Total carbohydrate concentration 1n raw,

          mesophilic, and thermophillc sludges versus
         date.

   11  i-
   10
  c
  0)
  c
  o
  01 4
  J 1 ~
  o
  JD
  i.
        -raw sludge

        •mesophilic sludge

        'thermophilic sludge
          Jun
  Jul

Date
Aug
                             25

-------
The addition  of  lime to a  sludge  already  conditioned with ferric  chloride
had little effect above  that  achieved  with the ferric chloride alone.  The
use of lime alone had little or no effect on the sludge.   The  dose of  ferric
chloride required to achieve very low GST values was generally between 4 and
5  g/1,  for the mesophilic  sludge.   A  dose  of >5  g/1  ferric chloride was
required  to  achieve good  results  with  the  thermophilic  sludge.    Although
higher  doses  of  ferric  chloride,  with  produced better  dewatering, also
effected  the  greatest pH  reduction,  equivalent results between mesophilic
and  thermophilic conditioned sludge  were  not  obtained  until the  pH was
reduced  to 4.3.   The  ferric chloride  dose  required to properly condition
mesophilic  sludge  was  always  less  than  that  required  to  condition
thermophilic  sludge.
                                     26

-------
Figure 11.   Mean  capillary suction time for mesophilic  and thermophilic sludges
            versus  date.
850


800


750



700
 I 650
   600
   550
 >>
 S 500
5 45°
   400


   350


   300
           	mesophilic sludge
           •	* thermophil ic sludge
                            *.
                            M
                            ' '
                            i i

                           ; i
                           ;  i
                          /   I'AI
                          '
              *  ii
              ii  I*
              n  i]
              u  ii
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                                    n
                                    M
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                                              if
                                                   A
                                                 /!
                                                              I   t
                                                                  '»
                   i\ |      I


                   '  "      '/  V i'   ^\
                   I         »  / '    v
                                                               r '•  «
Apr
May
  Jun

Date
                                                         Jul
                                                                     Aug

-------
                                 SECTION 6

                           DISCUSSION OF RESULTS

     In  this  study two  large  anaerobic reactors were  operated  In parallel
for several months at  each detention time.   The only difference  between the
two  reactors was  that  one  was  maintained  at 35°C  while  the other  was
maintained  at temperatures both above  and below 50°C.   It was  found that
high  volatile  acids  (primarily  propionic  acid)  were  present  when  the
temperature was above  50°C.  When  the temperature was  reduced to 49.5°C the
propionic  acid  fell  to low  levels and  the  overall performance  of  the
thermophilic  system approximated  that  of  the mesophilic  system.    Recent
studies  (7)   (8) have  indicated high volatile acids,   especially  propionic
acid,  under  thermophilic anaerobic conditions.    Thus  the  finding  here
concerning propionic acid is verified by others.  However,  no reference to
this  very sharp change  at  50°C has been  found in the  literature.    This
phenomenon should  be investigated  because  it may be a  limiting  step  in the
application of thermophilic  digestion.

     A  comparison  of  the performance  of  both  systems  under steady  state
conditions is given below.

TABLE 1.  SUMMARY OF PERFORMANCE OF MESOPHILIC AND THERMOPHILIC DIGESTERS
Detention
Time
25
25
15
15

Unit
T
M
T
M
Volatile
Solids
51.7
57.2
44.7
47.0
COD
D.M.
52.6
52.9
44.2
49.9
COD
Gas
53.2
63.1
53.3
56.8
Organic
Nitrogen
59.4
50.2
44.9
27.2
Grease
& Oil
65.0
71.2
59.3
67.4

Carbohydrate

-
56.2
68.8
     The  thermophilic  system data are  for  the period when  the  temperature
was 49.5°C.   This Table 1  reviews  the  percent removal of volatile  solids,
COD, organic  nitrogen,  grease and oil,  and  carbohydrate.   The  COD  removal
was calculated  on two bases;  direct measurement of COD in the effluent  and
calculation of  the COD equivalent of the methane gas produced during reactor
operation.  Carbohydrate data were only available at a 15-day detention time
while the other data  cover both 25-day detention time and 15-day detention
time.   It must  be  emphasized  that by all  normal parameters the operation of
each  reactor  system  was  satisfactory.    Alkalinity,  pH,  volatile  acids,
fraction  of methane  in  the gas were all  in  the normal range.   However,  as


                                     28

-------
indicated below the  mesophilic  unit consistently  out  performed  the
thermophilic unit  except for  organic  nitrogen breakdown.   In general  the
deg::ee of advantage which the mesophilic unit had over the thermophilic unit
was small, but  quantifiable.   As would be anticipated,  the performance  of
either  system  was  better  at  the  25-day  detention  time than  the  15-day
detention time.  Several  field-scale studies  of  thermophilic vs.  mesophilic
anaerobic digestion have  been  conducted in the U.S.  (9)  (10) (11).  All  of
these  have  indicated  essentially identical  performance  for both  systems.
The  data  obtained  in  this  study  could  be interpreted  to  support  the
conclusions  of these studies   or  to  refute it;  as the  difference  in
performance between the two systems was modest.

     Another  factor  which  was  investigated  in  this  study was  the
dewaterability  characteristics of the  sludge produced under mesophilic  and
thermophilic conditions.   This has been a point  of  controversy because  the
results  have   been  conflicting.     Some   studies  indicate   superior
dewaterability  (10) for  thermophilic   sludge, others  indicate the  reverse
situation (9).   The studies here clearly demonstrate that mesophilic sludge
is easier to  dewater than thermophilic sludge irrespective of  conditioning.
The CST of mesophilic  sludge was 2/3  to 1/2 that of  thermophilic  sludge  and
the dose of ferric chloride required  to achieve equivalent  CST  was  always
higher for  the  thermophilic sludge.

      Previous  reports on the  characteristics of thermophilic sludge  have
indicated that  the  supernatant was poor compared to mesophilic  sludge.   This
finding  was  confirmed  in  this study.    Not  only  was  the   thermophilic
supernatant much higher  in suspended solids but the soluble COD  was  always
1,000+ mg/1 higher  than  the mesophilic  supernatant.   Measurements  of  soluble
carbohydrate,  grease and oil and organic nitrogen were run to  determine  the
source of this  extra  COD.   It  was  found  that the  COD  of soluble  organic
fractions could  not  account  for  all  of  the  extra soluble  COD  in  the
thermophilic  sludge supernatant.   For  example,  the  difference between  the
soluble organic  nitrogen  in  the  two  systems was  only  2 mg/1; the  difference
in soluble  oil and grease was only  150 mg/1  and the difference  in  soluble
carbohydrate was only at most 75 mg/1.   Measurement of  soluble  sulfide  in
the units gave values  in  the range of 4-8 mg/1 which  again could not  account
for the COD difference.   Another topic  for  future research is  the  nature  of
this  extra soluble  COD.

      Finally,  the question  of  odor  must be  addressed.  It has been reported
that  thermophilic  sludge  is  odorous compared to mesophilic  sludge.   This
phenomenon  was confirmed  in  this  study;  although quantitative  odor
measurements were  not made.   An odor  panel made of  the  personnel in   the
Environmental  Studies  Center voted  unanimously that  thermophilic  sludge  had
a  more disagreeable odor  than mesophilic sludge.   Two votes were taken,  once
when  the volatile  acids  were  high  and again when they were  low.  In both
situations  the  thermophilic  sludge  was  rated  most disagreeable, although  it
was  less so  under low  volatile acid conditions.

      The bulk  of the data generated in  this  study indicates that anaerobic
digestion of  municipal sewage sludge  should  be  performed under  mesophilic
conditions rather than thermophilic conditions.


                                     29

-------
                                  REFERENCES

1.    Fisher Scientific Catalogue - 1986,  p.  250.

2.    Standard Methods  for  the  Examination of  Water and  Wastewater APHA,
     AWWA, WPCF, 15th Ed. (1985).

3.    Dubois, M., et al, "Colorimetric Method for Determination of  Sugars  and
     Related Substances", Analytical Chemistry 28.  350 (1956).

4.    Herbert, D., et al., "Determination of Total Carbohydrate".   In Methods
     in Microbiology 5B.  Ed. Norris  J.  R.  and,  Robbins D. W. , 265  Academic
     Press, New York.

5.    Kampmeier,   D.  T.,  et  al,  "Carbohydrate  as a  Measure  of  Biomass  in
     Expanded Bed Anaerobic Filters", Dept.  of Civil  Engineering,  University
     of Illinois 208 N. Romine Urbana, IL,  61801.

6.    Vesilind,   P.   A.,   Zhang,  G.,  "Technique  for  Estimating  Sludge
     Compactibility  in  Centrifugal   Dewatering".    Journal  of   the Water
     Pollution Control Federation. 56. 1231 (1984).

7.    Lin,  C. Y., "Temperature  Characteristics of the Methanogenesis  Process
     in Anaerobic Digestion", Water Science and  Technology.  19. 299  (1987).

8.    Gosh,  S.,  "Improved Gasification  by Two-Phase  Anaerobic Digestion".
     Journal  of the  Environmental  Engineering  Division.  ASCE.   113  1265
     (1987).

9.    Buhr,  H.  and  Andrews,  J.  "Review  Paper,   The  Thermophilic  Anaerobic
     Digestion Process".  Water Research. 11,  129 (1976).

10.  Garber,  W. F.,  "Operating Experience  with Thermophilic  Anaerobic
     Digestion". Journal of the Water Pollution  Control Federation.  54. 1170
     (1982).

11.   Rimkus, R.  R. ,  et.  al. ,  "Full  Scale  Thermophilic  Digestion  at   the
     West-Southwest Sewage Treatment Works,  Chicago,  Illinois".   Journal of
     the Water Pollution Control Federation.  54,  1447  (1982).
                                   30

-------
Table A-l.  RAW SLUDGE DATA SHEET (   ) - Indicates Dilution Correction Factor
Date
Obtained
12/1/86
12/8/86
12/15/86
12/22/86
12/29/86
1/5/87
1/12/87
1/19/87
1/19/87
1/19/87
2/9/87
2/16/87
2/23/87
3/2/87
3/9/87
3/16/87
3/23/87
3/23/87
3/23/87
4/13/87
A/13/87
4/27/87
4/27/87
4/27/87
5/18/87
5/18/87
6/1/87
6/1/87
6/15/87
6/15/87
6/29/87
7/2/87
7/6/87
7/9/87
7/13/87
7/16/87
7/17/87
7/17/87
7/27/87
7/27/87
8/3/87
8/3/87
8/10/87
8/10/87
8/10/87
Date
1st Feed
12/2/86
12/9/86
12/16/86
12/23/86
12/30/86
1/6/87
1/13/87
1/20/87
1/27/87
2/3/87
2/10/87
2/17/87
2/24/87
3/3/87
3/10/87
3/17/87
3/25/87
3/31/87
4/7/87
4/14/87
4/21/87
4/28/87
5/5/87
5/12/87
5/19/87
5/26/87
6/2/87
6/9/87
6/16/87
6/23/87
6/30/87
7/3/87
7/7/87
7/10/87
7/14/87
7/17/87
7/20/87
7/24/87
7/28/87
7/31/87
8/4/87
8/7/87
8/11/87
8/14/87
8/17/87
Date
End Feed
12/8786"
12/15/86
12/22/86
12/29/86
1/5/87
1/12/87
1/19/87
1/26/87
2/2/87
2/9/87
2/16/87
2/23/87
3/2/87
3/9/87
3/16/87
3/24/87
3/30/87
4/6/87
4/13/87
4/20/87
4/27/87
5/4/87
5/11/87
5/18/87
5/25/87
6/1/87
6/8/87

6/22/87
6/29/87
7/2/87
7/6/87
7/9/87
7/13/87
7/16/87
7/19/87
7/23/87
7/27/87
7/30/87
8/3/87
8/6/87
8/10/87
8/13/87
8/16/87
8/22/87
                                                        % Volatile Solids
                                    5.
                                    5.
                                        (.55)=
 ,96(.6)
 .9(.65)
4.5(.8)
4.4(.8)
5.13(.7)
3.6
3.8
3.6
3.5
3.5
                                    5.27(.66)= 3.5
                                    4.35(.8) =
                                      4(.65)
                                      5(.64)
                                    3.85(.9) =

                                    s!85(.9) =
                                     .1(.68)
                                      0(.76)
                                      4(.64)
           3.5
           3.5
           3.5
           3.5
           3.5
           3.5
           3.5
           3.8
           3.45
                                    5.24(.67)= 3.5
                                    5.42(.65)= 3.5
                                    5.61(.63)= 3.5
                                    3.79(.93)= 3.5
                                    3.52(1.0)= 3.5
                                    3.F2(1.0)= 3.4
                                    3.71(.93)= 3.45
                                    3.81(.92)= 3.5
                                    3.53(1.0)= 3.53
                                    3.86(.92)= 3.55
                                    4.01(.87)= 3.5
                                    3.57(1.0)= 3.57
                                    3.84(.92)= 3.5
                                    4.21(.83)= 3.
                                          ,76)= 3.
 ,60(,
 ,14(.68)=
 ,00(.7)
 .5
 .5
3.5
3.5
                                                                .7
                                                                .1
                                    4.66(.75)= 3.5
81.
85.
86.0
84.6
85.A
85.4

82.0
80.0
80.0
81.0
84.2
81.6
79.1
76.4
75.5
81.6
81.8
82.21
82.22
81.87
81.97
82.87
82.59
80.91
79.9
80.60
79.57
79.06
78.93
79.76
80.36
80.10
80.4
79.4

78.7
78.48
78.52
78.78
76.88
79.73
81.07
81.29
80.2
                                       31

-------
Table A-2.
FULL STRENGTH RAW SLUDGE -  (All Units mg/1 Except pH)
Date
Obtained
12/1/86
12/8/86
12/15/86
12/22/86
12/29/86
1/5/87
1/12/87
1/19/87
1/19/87
1/19/87
2/9/87
2/16/87
2/23/87
3/2/87
3/9/87
3/16/87
3/23/87
3/23/87
3/23/87
4/13/87
4/13/87
4/27/87
4/27/87
4/27/87
5/18/87
5/18/87
6/1/87
6/1/87
6/15/87
6/15/87
6/29/87
7/6/87
7/9/87
7/13/87
7/16/87
7/17/87
7/17/87
7/27/87
7/27/87
8/3/87
8/3/87
8/10/87
8/10/87
8/10/87
pH
5.6
5.6
5.6
5.2
5.5
6.0
5.5
5.6
5.4
5.3
5.8
5.7
5.6
5.3
5.5
5.6
5.8
5.4
5.5
5.6
5.6
5.5
5.6
5.4
5.8
5.6
5.7
5.6
5.8
5.5
5.5
5.8
5.6
5.4
—
5.5



5.65
5.5
5.4
5.4
5.54
Vol.
Acids
2732
1297
1675
1669
941
1234
1457
2297
3036
3081
2005
26^5
3400
3081
1858
1978
1700
2950
2651
2024
2904
2196
2965
2267
2509
2904
2419
3223
2955
2884
1751
1812
1600
1943
-
1680
1484
1720
1609
2135
2934
2368
2368
NM
Alk.
1900
2150
1700
1250
900
1300
1500
1350
1600
1550
1150
1300
1650
1550
1100
1250
900
1350
1450
1525
1100
900
1250
1125
1200
1150
950
1550
1300
1350
1500
1150
950
950
-
950
1075
1050
1000
1500
1300
1250
1250
1750
Total
COD
69,555
56,832
43,593
47,923
37,407
33,703
45,550
87,339
85,064
71,420
62,680
104,976
89,472
72,990
55,594
53,681
55,264
56,345
65,078
76,800
75,072
80,998
64,232
53,136
67,200
69,312
71,064
65,739
58,784
70,168
49,138
49,046
52,192
53,360
50,986
54,880
55,987
49,935
57,882
54,802
61,797
69,696
69,215
74,131
NH3
183
63
45
128
52
67
83
117
224
259
178
301
273
160
151

14
150
196
119
208
164
196
199
121
229
131
211
224
150
132
200
132
173
191
187
177
141
171
191
183
166
-
215
TKN
1624
1232
1176
1120
728
784
1484
1960
1964
1925
1750

2128
1920
1456
1389
1946
2134
1788
2467

2251
2066
1557
2198
2310
2436
2257
2285
2285
1840
1904
1946
2022
1932
1991
2041
1778
1915
1789
1988
2240
-
2217
Org.
Nit.
1441
1169
1130
991
695
716 '
1400
1842
1540
1666
1571
1302
1855
1760
1304
_
1931
1983
1985
2348

2087
1848
1357
2076
2080
2305
2046
2061
2135
1707
1704
1814
1848
1741
1804
1864
1637
1744
1598
1804
2073
-
2003
Oil &
Grease
_
5850
__
7315
5545
7525
13030
12242
11026
7308
12251
10945
11026
9143
7548
11216
10416
9279
9709

6977
9651
7446
10413
10528
10772
10319
11007
10938
9216
7253
8086
8549
7857
8221
8257
7901
8231
7876
-
11103
-
10320
Total
CH20



























8,500
8,500
11,460
5,510
5,920
5,220
6,450
5,720
7,550
4,760
6,790
12,500
11,400
-
-
-
                                       32

-------
Table A-3.  DILUTED RAW SLUDGE FEED    (All Units mg/1 Except for pH)
                   Vol.  Total
     Period  Fed   Acids   Alk. COD     NH3   TKN
Org. Oil &   COD/ Total
Nit. Grease  V.S. CH20
12/2/86
12/9/86
12/16/86
12/23/86
12/30/86
1/6/87
1/13/87
1/20/87
1/27/87
2/3/87
2/10/87
2/17/87
2/24/87
3/3/87
3/10/87
3/17/87
3/25/87
3/31/87
A/7/87
4/14/87
4/21/87
4/28/87
5/5/87
5/12/87
5/19/87
5/26/87
6/2/87
6/9/87
6/16/87
6/23/87
6/30/87
7/7/87
7/10/87
7/14/87
7/17/87
7/20/87
7/24/87
7/28/87
7/31/87
8/4/87
8/7/87
8/11/87
8/14/87
8/17/87
12/8/86
12/15/86
12/22/86
12/29/86
1/5/87
1/12/87
1/19/87
1/26/87
2/2/87
2/9/87
2/16/87
2/23/87
3/2/87
3/9/87
3/16/87
3/24/87
3/30/87
4/6/87
4/13/87
4/20/87
4/27/87
5/4/87
5/11/87
5/18/87
5/25/87
6/1/87
6/8/87
6/15/87
6/22/87
6/29/87
7/2/87
7/9/87
7/13/87
7/16/87
7/19/87
7/23/87
7/27/87
7/30/87
8/3/87
8/6/87
8/10/87
8/13/87
8/16/87
8/22/87
2049
1297
1675
1669
941
1234
1457
1378
1821
2157
1604
1482
2040
2003
1486
1582
1190
1953
2121
1316
1858
1976
2076
2040
1706
2207
1572
3126
1921
1817
1628
1812
1488
178R
—
1546
1726
1720
1480
1772
2229
1610
1657
NM
1425
2150
1700
1250
900
1300
1500
750
960
1085
920
715
990
1007
880
1000
630
891
1160
991
704
810
875
1013
816
874
618
1039
845
851
1395
1150
884
874
-
874
935
1050
920
1245
988
850
875
1312
52,
56,
43,
47,
37,
33,
A5',
52,
51,
49,
50,
57,
53,
47,
44,
42,
38,
37,
52,
49,
48,
72,
44,
47,
45,
52,
46,
44,
38,
44,
45,
49,
48,
49,
50,
50,
48,
49,
53,
45,
47,
47,
48,
55,
166
832
593
923
407
703
550
403
038
994
144
736
683
443
475
945
685
188
061
920
046
898
962
822
696
677
192
045
210
205
698
046
539
091
986
490
709
935
251
485
121
393
450
598
137
63
45
128
52
67
83
70
134
181
142
165
163
104
120

10
99
157
77
133
147
137
179
82
174
85
141
146
94
123
200
122
159
191
172
154
141
157
159
139
113
-
161
1218
1232
1176
1120
728
784
1484
1.176
1178
1347
1400

1276
1248
1164
1111
1362
1309
1430
1603
1484
2025
1431
1601
1495
1756
1583
1512
1485"
1440
1711
1904
1809
1859
1932
1831
1775
1778
1761
1484
1510
1523
-
1662
1081
1169
1130
991
695
716
1400
1105
924
1166
1257
716
1113
1144
1043

1352
1309
1588
1526
1350
1878
1294
1221
1412
1581
1498
1371
1340
1345
1588
1704
1687
1700
1741
1659
1621
1640
1604
1326
1371
1409
-
1501
••»
_
5850

7315
5545
7525
7818
7345
7718
5846
6738
6567
7166
7314
6038
7851
6875
7423
6311
6998
6279
6756
6701
7081
8001
7002
6914
7155
6891
8571
7253
7521
7866
7857
7564
7184
7902
7571
6537
-
7550
-
7740
1.637
1.629
1.300
1.452
1.413
1.315

1.746
1.772
1.689
1.720
1.905
1.827
1.578
1.617
1.625
1.355
1.299
1.809
1.735
1.677
2.541
1.550
1.654
1.614
1.735
1.633
1.577
1.372
1.585
1.626
1.790
1.750
1.764
-
1.807
1.779
1.781
1.913
1.689
1.689
1.679
1.696
-




























5525
5355
10657
5510
5505
4802
6450
5262
6568
4760
6246
10375
8664
-
-
-
                                       33

-------
Table A-4.    pH-ALKALINITY  -VOLATILE ACIDS  (All  Units mg/1  Except pH)

Date
12/3/86
12/5
12/8
12/10
12/12
12/15
12/17
12/19
12/22
12/24
12/26
12/27
12/29
12/31
1/2/87
1/3
1/4
1/5
1/7
1/9
1/10
1/12
1/14
1/16
1/17
1/18
1/19
1/21
1/23
1/25
1/26
1/28
1/30
2/1
2/4
2/6
2/8
2/9
2/11
2/13
2/16
2/18
Thermo
philic
7.3
—
_
7.3
_
_
7.3
-
_
7.35
—
—
-
7.35
—
-
_
_
7.3
_
_
—
7.2
—
—
—
-
7.2
-
—
—
7.3
7.3
-
7.3
7.3
-
7.3
7.3
7.3
7.2
7.3
  Meso-
philic

   7.1


   7.1


   7.06


   7.1



   7.15
                        7.1
                        7.0
                        7.1
                        7.1
                        7.1

                        7.15
                        7.1

                        7.1
                        7.1
                        7.1
                        7.1
                        7.1
                                      Alkalinity
                                   Thermo-    Meso-
                                 philic     philic
                                    3850
          3550
                                    4100      3900


                                    4000      3900


                                    4050      3900
                                    4250
          4200
4450
4150
                         3860
                         3650
4250



4150


4250



4500


4500
                         3950



                         3750


                         4000



                         4250


                         4150
                       Volatile Acids
                      Thermo-    Meso-
                    philic     philic
340.
340.
395.6
404.8
496.8
552.
163.2
182.2
333.9
384.6
506.
506.
657.8
748.9
799.5
840.
880.
951.3
_
1001.9
961.
961.
1001.9
1032.2
941.
961.
1012.
1062.6
1163.8
1113.
1133.4
1163.8
1335.8
1315.
1415.
1400.
1425.
1386
1425.6
1534.5
1465.2
1346.4
220.8
220.8
404.8
395.6
487.6
414.
130.5
151.8
161.9
151.8
111.
132.
151.8
192.3
111.3
101.
101.
192.3
232.
212.5
101.
91.
151.8
121.4
101.
101.
101.
111.3
111.3
81.
91.1
111.3
121.4
101.
151.
101.
101.
101.
111.1
131.3
111.1
111.1
                                       34

-------
Table A-4.
          pH-ALKALINITY -VOLATILE ACIDS (Continued)

          pH                 Alkalinity           Volatile Acids
Date

2/20
2/21
2/22
2/23
2/25
2/27
3/1
3/2
3/5
3/6
3/7
3/9
3/11
3/13
3/15
3/16
3/18
3/20
3/23
3/25
3/27
3/30
4/1
4/3
4/6
4/8
4/10
4/13
4/1.5
4/17
4/20
4/22
4/24
4/27
4/29
5/1
5/4
5/6
5/8
5/11
5/13
5/15
  Thermo
philic

    7.3
    7.3
    7.35
    7.35

    7.4
    7.4
    7.35

    7.3
    7.25
    7.35
    7.35
    7.35
    7.3
    7.3
    7.4
    7.35
    7.35
    7.4

    7.45
    7.35
    7.3
    7.3
    7.25
    7.65
    7.45
    7.45
    7,
    7.
    7.
    7.
  .35
  ,35
  ,35
  ,55
7.4
7.5
7.45
7.5
7.55
          Meso-
        philic

           7.1
           7.1
           7.1
           7.1

           7.15
           7.1
           7.1

           7.1
           7.15
           7.15

           7.25
           7.25
           7.15
           7.15
           7.15
           7.1
           7.1
           7.05
           7.2
           7.05
           7.2
7.05
7.15
7.1
7.05
7.05

 7.1
 7.2
 7.1
 7.2
 7.2
 7.25
 7.2
 7.1
 7.3
           Thermo-    Meso-
         philic     philic
            4850
            5100
            4750
            4725
4350


4450


 450


4375


4320


4350


4275
4150



4350



4400



4150


3850


4400


4100


4250


4000


4100


4125


4225
Thermo-
philic
1197.9
1009.8
762.3
337.6
188.1
212.
227.7
445.
426.
475.
564.3
633.6
800.
796.9
739.2
841.5
811.8
673.2
405.9
138.6
101.2
158.4
158.4
207.9
222.8
282.0
396.0
243.0
124.0
134.0
153.5
109.0
351.5
158.4
148.5
252.5
-
273.6
207.9
158.4
Meso-
philic
91.08
101.
91.08
91.08
119.6
112.
111.3
101.2
111.3
111.
105.8
101.2
130.
87.4
73.6
73.6
50.6
60.7
90.08
91.08
60.72
80.96
86.0
86.02
73.6
81.0
132.0
81.0
86.0
81.0
116.4
73.6
131.56
80.96
111.32
111.32
101.2
96.14
86.02
96.14
                                       35

-------
Table A-4.
pH-ALKALINITY -VOLATILE ACIDS (Continued)
PH

Date
5/18
5/20
5/22
5/24
5/27
5/28
6/1
6/3
6/4
6/5
6/8
6/10
6/11
6/12
6/15
6/17
6/19
6/22
6/24
6/26
6/27
6/29
7/1
7/3
7/6
7/9
7/11
7/13
7/16
7/18
7/20
7/23
7/25
7/27
7/30
8/3
8/6
8/8
8/10
8/13
8/15
8/17
8/23
Thermo
philic
7.35
7.45
7.45
_
7.5
_
7.4
7.45
-
7.45
7.35
7.35
-
—
7.2
7.50
7.45
7.25
7.30
7.35
—
7.35
7.35
_
7.4
7.4
-
7.4
7.25
-
7.45
7.4
-
7.4
7.35
7.3
7.3
—
7.25
7.25
-
7.34

Meso-
philic
7.2
7.25
7.3
_
7.25
_
7.15
7.3
-
7.3
7.15
7.2
-
_
7.10
7.50
7.35
7.30
7.10
7.10
-
7.05
7.05
-
7.1
7.1
-
7.15
7.05
-
7.10
7.20
-
7.05
7.05
7.05
7.0
-
7.0
6.95
-
7.10

Alkalinity
Thermo-
philic
_
4425
_
«.
4350
_
—
4525
—
-
-
4800
-
-
-
5200
-
-
5050
-
-
-
4750
-
4800
5000
-
5375
5500
-
5000
4900
-
5050
5100
4950
4925
-
4775
4700
—
-
End 15 Day D
Meso-
philic

4275
_
^
4275
_
—
4350
—
—
-
4600
-
-
-
4550
-
—
4450
-
-
-
4300
—
4150
4550
-
4300
4450
-
4250
4400
-
4500
4350
4300
4350
—
4250
4200
—
—
.T.
Volatile
Thermo-
philic
138.6
133.65
128.7
138.6
183.2
188.1
143.6
232.65
168.3
148.5
178.?
346.5
386.1
455.4
574.0
524.7
267.3
227.7
376.2
287.1
260.0
143.6
178.2
200.0
217.0
158.0
200.0
178.0
217.8
250.0
168.3
198.0
160.0
183.2
237.6
267.0
416.0
270.0
178.0
148.0
200.0
356.0
Acids
Meso-
philic
60.72
86.02
91.08
91.08
101.2
91.08
91.08
212.5
117.4
101.2
131.56
101.2
136.62
111.3
131.0
141.7
141.7
121.4
172.0
172.0
-
121.4
141.7
130.0
136.0
121.0
150.0
121.0
141.7
120.0
121.4
141.7
160.0
131.6
121.4
131.0
162.0
130.0
192.0
126.0
150.0
208.0

-------
Table A-5.
Date
                  SPECIATED ACID
        (Expressed as % Volatile Acid)
    Thermophilic
LAP
12/5/86
12/8/86
12/10/86
12/12/86
12/15/86
12/17/86
12/19/86
12/22/86
12/24/86
12/26/86
12/29/86
12/31/86
1/2/87
1/5/87
1/7/87
1/9/87
1/12/87
1/14/87
1/16/87
1/21/87
1/23/87
1/28/87
2/2/87
2/6/87
2/9/87
2/11/87
2/13/87
2/16/87
2/18/87
2/20/87
2/23/87
2/25/87
2/27/87
3/2/87
3/5/87
3/11/87
3/13/87
3/16/87
3/18/87
3/20/87
3/25/87
3/27/87
6,
7,
9
6
3

.3
.2
.2
.7
.6
-
17.
40.















0
0
0
0
0
1

2
3
5
4
3
2
2
1
1
2
1
0
1.
2.
0.
2.
1.
1.
1.
1.
0.
1.
1.
0.
0.
1.
9.
.7
.7
.8
.3
.7
.6
.6
.4
.1
.8
.6
.7
.2
.0
.2
.5
.0
.1
.7






9
0
9
8
3
3
3
7
3
3
9
4
4
0
4
4
6



















19,
25
25
22
15
_
8
12
8
9
4
7
5
7
4
7
4
4
6
0
2
5
6
9
4
3
2
4
7
2
14
14
44
19
16
8
8
7
7
8
0
3
.1
.3
.0
.8
.8

.2
.5
.3
.4
.6
.7
.4
.1
.9
.7
.1
.9
.2
.0
.6
.6
.4
.5
.7
.8
.0
.6
.6
.9
.2
.1
.4
.5
.9
.8
.9
.1
.4
.3
.4
.5
35,
39
37
35
29
7
35
22
15
12
13
9
6
7
7
6
4
10
6
8
7
7
5
5
7
0
4
4
8
8
19
37
29
35
40
12
12
10
13
10
19
23
.0
.9
.1
.6
.1
.8
.8
.2
.3
.2
.0
.4
.5
.2
.7
.1
.5
.3
.1
.9
.8
.2
.3
.2
.4
.7
.8
.3
.5
.4
.9
.1
.6
.1
.0
.1
.5
.3
.9
.1
.0
.6
39.
27.
28.
34.
51.
92.
38.
61.
74.
72.
82.
80.
86.
84.
79.
84.
90.
83.
86.
91.
89.
86.
87.
89.
87.
90.
92.
90.
82.
88.
69.
45.
20.
40.
39.
76.
76.
81.
77.
79.
77.
72.
6
6
7
9
5
2
2
4
5
0
1
4
6
0
8
9
5
4
2
1
2
0
3
7
2
6
9
4
4
1
6
7
2
9
4
9
6
4
3
7
3
2
B
Mesophilic
F
5.2
-
15.5
9.4
7.1
_
2.7
7.8
12.4
10.8
_
12.1
—
5.7
5.4
9.1
9.1
11.2
10.5
0.0
9.1
10.2
11.6
5.5
6.8
5.4
6.4
6.7
11.7
10.3
0
2.5
14.2
11.4
7.8
5.8
8.8
0
8.7
11.1
6.6
4.7
L
17.8
29.8
46.6
26.8
_
—
7.4
21.2
35.1
36.7
30.7
49.7
_
22.4
28.2
36.5
40.1
38.8
42.3
46.8
43.6
40.0
34.1
35.4
50.4
37.7
36.7
33.7
58.3
41.2
53.5
32.5
66.3
57.1
75.4
32.0
46.8
77.9
46.5
47.4
20.8
11.2
A
11.7
8.4
20.2
14.6
13.5
25.8
14.9
13.1
17.4
15.4
19.0
16.1
21.6
9.9
17.5
17.2
19.8
19.5
18.8
15.4
22.7
22.3
17.1
9.8
11.6
19.7
10.2
9.2
11.7
26.8
23.1
24.9
19.1
13.7
16.8
18.5
19.4
13.0
20.4
19.2
24.3
12.2
P
65.2
61.8
17.7
49.2
79.4
74.2
68.9
57.9
35.1
37.1
50.3
22.1
78.4
62.0
48.8
37.2
31.0
30.5
28.5
37.8
24.6
27.6
37.2
49.3
31.1
37.2
46.7
50.3
18.3
21.6
23.4
40.0
29.4
74.8
0
43.7
26.9
9.1
24.4
22.4
48.3
71.9
                                                                          B
                                        37

-------
Table A-5.
Date
          SPECIATED ACID (Continued)
        (Expressed as % Volatile Acid)
    Thermophilic
LAP
3/30/87
A/1/87
4/3/87
4/6/87
4/8/87
4/10/87
4/13/87
4/15/87
4/17/87
4/20/87
4/22/87
4/24/87
4/29/87
5/1/87
5/4/87
5/6/87
5/8/87
5/11/87
5/13/87
5/15/87
5/18/87
5/20/87
5/22/87
5/27/87
5/29/87
6/1/87
6/5/87
6/8/87
6/10/87
6/12/87
6/15/87
6/17/87
6/19/87
6/22/87
6/25/87
6/26/87
6/29/87
7/1/87
7/6/87
7/9/87
7/13/87
7/16/87
7/20/87
1.1
2.8
0.9
1.0
0.9
0.8
0.6
0.9
1.6
1.2
1.5
0.0
1.2
1.4
1.8
1.7
0.5
0.9
2.4
_
—
1.2
1.4
4.5
4.9
3.3
2.4
-
2.7
2.2
1.0
0.3
1.0
2.2
0.4
0.3
1.0
2.2
1.1
1.1
1.0
1.9
2.0
7.0
14.0
5.5
8.7
4.0
4.9
3.7
2.7
4.3
6.0
7.2
3.7
0
4.6
0.9
_
1.7
2.8
5.7
3.4
1.3
5.9
5.9
4.8
6.9
5.5
-
-
-
2.9
1.3
1.0
3.5
7.8
1.7
3.1
12.2
7.1
8.7
8.8
8.0
7.2
6.3
46.8
56.2
47.4
49.8
28.7
30.9
18.4
41.1
44.1
36.1
54.6
49.1
58.5
70.59
40.2
41.4
29.1
58.0
72.4
52.4
36.6
62.41
67.0
75.2
54.4
49.4
69.9
32.4
42.6
29.7
16.0
18.5
38.7
45.1
23.7
30.4
76.1
76.6
83.7
84.6
87.0
78.7
83.5
45.1
27.0
46.2
40.5
66.4
63.4
77.4
55.3
49.9
56.7
36.8
47.2
40.3
23.5
56.9
56.9
68.7
38.4
19.5
44.1
62.1
30.4
25.7
15.5
33.8
41.8
27.4
67.5
54.7
65.2
82.0
80.2
56.8
45.0
74.2
66.2
10.7
14.0
6.4
5.5
3.9
12.2
8.3
B
    Mesophilic
LAP
1.5
2.2
1.4
2.2
1.1
1.7
0.0
3.8
0
0
0
2.5
11.7
12.8
6.9
2.9
1.9
1.9
2.0
1.0
1.7
_
2.1
3.1
7.6
9.7
5.8
5.7
9.5
8.9
6.7
1.5
2.0
0.8
0.6
_
0.5
3.9
9.9
0.9
2.1
—
1.0
12.5
7.3
6.7
14.1
7.4
11.1
17.0
12.3
17.0
11.6
9.7
5.3
9.2
4.0
2.1
—
9.1
5.9
6.4
6.2
5.3
6.9
5.9
4.3
3.8
4.5
-
-
—
18.7
9.6
17.3
16.6
7.7
11.1
10.6
9.9
8.5
9.1
11.6
19.9
9.7
13.0
5.7
43.7
11.1
11.6
6.1
9.1
26.7
20.3
24.7
8.5
15.8
10.2
7.6
17.4
11.3
25.3
10.1
16.1
42.0
13.5
17.5
22.5
14.8
11.1
13.4
27.0
35.7
20.0
49.6
49.4
39.7
56.3
45.0
28.6
45.7
39.0
36.5
50.0
39.8
40.5
44.1
42.9
32.7
80.3
46.8
80.8
72.2
85.4
78.1
58.2
63.6
58.2
79.9
74.5
82.0
71.4
65.7
79.6
71.7
78.8
76.1
49.5
79.3
75.5
70.6
77.2
77.5
75.2
58.8
58.5
74.2
40.9
22.9
44.1
24.8
36.2
62.9
42.6
50.5
53.0
27.5
41.2
46.9
•33.7
47.4
53.2
                                                                          B
                                       38

-------
Table A-5.
Date
          SPECIATED ACID (Continued)
        (Expressed as % Volatile Acid)
    Thermophilic
LAP
7/24/87
7/27/87
7/30/87
8/3/87
8/6/87
8/10/87
8/13/87
2.3
0.9
1.0
2.5
1.3
6.0
6.0
6.3
4.8
3.4
0.3
0.7
0.3
1.0
77.4
79.1
78.5
41.0
26.7
85.7
86.9
4.0
15.1
17.1
56.2
71.3
8.0
6.0
B
Mesophilic
   A      P
                                              3.0
3.8
7.2
10.2
3.3
3.9
f_l
—
8.1
80.7
36.7
66.7
26.4
33.3
30.4
15.5
12.1
53.1
30.0
69.7
66.6
66.6
B
 F=Formic Acid
 L=Lactic Acid
 A=Acetic Acid
 P=Propionic Acid
 B=Butyric Acid
                                        39

-------
Table A-6.
GAS PRODUCTION
Gas
Date

11/28/86
11/29
11/30
12/1
12/2
12/3
12/4
12/5
12/6
12/7
12/8
12/9
12/10
12/11
12/12
12/13
12/14
12/15
12/16
12/17
12/18
12/19
12/20
12/21
12/22
12/23
12/24
12/25
12/26 ,
12/27
12/28
12/29
12/30
12/31
1/1/87
1/2
1/3
1/4
1/5
1/6
1/7
1/8
1/9
Production
Thermo-
philic
41.6
41.2
46.8
48.26
34.8
35.9
46.1
38.6
35.2
44.1
44.8
40.9
48.4
49.5
50.3
51.9
44.7
46.2
43.8
39.5
42.9
52.2
49.5
54.6
50.1
50.4
44.1
43.2
45.5
42.8
*
•*
47.1
41.5
42.7
44.6
40.7
41.1
36.96
36.7
37.5
35.8
34.8
- Liters
Meso-
philic
37.2
42.8
44.9
39.5
49.3
49.8
44.8
43.2
38.4
43.5
40.8
44.5
51,1
47.1
50.6
58.4
45.7
57.5
41.9
45.4
46.9
46.9
56.2
_#
54.3
50.4
44.6
51.8
53.8
52.1
•K-
*
37.96
38.4
38.7
38.6
41.8
42.6
39.02
36.9
38.1
38.0
41.1
                                       % of
                                    Thermo-   Meso-
                                    philic    philic
                     Amount of City - Liters
                          Thermo   Meso-
                          philic   philic
                                    59.6

                                    62.3

                                    577?


                                    60.1

                                    60.3

                                    61.2
                                    61.1

                                    61.8

                                    58.5
                                    59.2
                                    58.5

                                    57.5
                                    58.6

                                    59.2

                                    61.6
            61.6

            59.6

            57.1


            61.3

            60.3

            60.A
63.2
63.2
60.9
60.0
61.3
61.0
             60.1

             59.8

             55.1
            60.9
            60.2

            59.7
            58.9

            60.1

            •59.4
28.8

22.4

22.3


26.9

29.2

30.8
30.6

27.3

26.6
27.9
24.3

25.6
21.7

22.2

21.4
24.3

29.7

24.7


25.0

30.8

30.6
29 .-2
24.9
31.8
37.9
27.8
34.7
32.6

26.3

29.6
23.1
23.1

23.0
23.0

22.9

24.4
                                       40

-------
Table A-6.
GAS PRODUCTION (Continued)
      Gas Production  -  Liters
Date      Thermo-   Meso-
          philic    philic
1/10
1/11
1/12
1/13
1/14
1/15
1/16
1/17
1/18
1/19
1/20
1/21
1/22
1/23
1/2A
1/25
1/26
1/27
1/28
1/29
1/30
1/31
2/1
2/2
2/3
2/4
2/5
2/6
2/7
2/8
2/9
2/10
2/11
2/12
2/13
2/14
2/15
2/16
2/17
2/18
2/19
2/20
2/21
33.7
38.5
36.7
31.7
38.2
A9.7
A6.5
36. A
36.5
39.5
A1.7
3A.3
A2.3
A7.8
A2.9
A2.1
A1.5
37. A
38.0
39.1
39.2
39.9
37.5
39.6
37.0
35.7
3A.O
36.5
36.9
39.6
38.5
36.8
37.8
38.9
A0.6
A0.86
A2.1
39.3
37.5
37.1
3A.3
A0.7
*
38.8
A0.3
A0.6
36.98
38.2
38.6
38.9
38.7
39.0
38. A
A5.A
32.8
A1.7
A6.A
A9.1
37.9
A0.6
38.8
39.6
38.8
A1.9
A3.1
A0.5
AA.5
A2.9
A3. A
A2.0
A3.1
A2.9
A3. 7
A0.7
38.2
37.6
A0.3
A1.9
39.8
A3. 9
39.9
37.8
37.6
37.7
37.8
39.5
               % of CH4
            Thermo-   Meso-
            philic    philic
                                    60.7

                                    59.7

                                    59.2


                                    60.1

                                    59.0

                                    58.7


                                    57.7

                                    59.3

                                    57.0


                                    58.5

                                    60.0

                                    60.1


                                    60.0

                                    59.7

                                    58.8


                                    60.2

                                    60.A

                                    61.9
                      59.3

                      59.8

                      61.1


                      60.5

                      58.3

                      58.8


                      58.A

                      60.A

                      57.0


                      57.7

                      60.1

                      60.0


                      61.1

                      60.6

                      60.0


                      57.3

                      62.8

                      60.3
Amount of Oty - Liters
     Thermo   Meso-
     philic   philic
     22.3

     22.8

     27.5


     23.7

     20.2

     28.1
     23.2

     21.A

     21.9


     23.1

     22.6

     23.9


     23.7

     22.A

     25.2
2A.O

22.8

23.8


23.2

19.1

26.6
23.9
22.5
22.3
23.7
23.9
23.9
25.7

26.1

25.9


2A.9

22.8

25.1


22.9

23.6

22.8
                                       Al

-------
Table A-6.

Date

2/22
2/23
2/24
2/25
2/26
2/27
2/28
3/1
3/2
3/3
3/4
3/5
3/6
3/7
3/8
3/9
3/10
3/11
3/12
3/13
3/14
3/15
3/16
3/17
3/18
3/19
3/20
3/21
3/22
3/23
3/24
3/25
3/26
3/27
3/28
3/29
3/30
3/31
4/1
4/2
4/3
4/4
4/5
Gas Production
Thermo-
philic
#
52.5
43.5
48.4
46.3
38.9
37.5
41.4
42.8
38.0
*
_
30.7
33.9
35.6
36.3
35.9
33.7
34.5
35.5
34.7
35.1
31.6
33.1
31.9
35.1
34.8
37.1
36.9
36.3
39.8
38.7
40.9
47.1
47.9
40.7
44.6
44.3
39.4
43.6
43.4
47.4
40.7
- Liters
Meso-
philic
44.2
41.5
38.0
44.0
44.5
43.0
43.5
47.3
45.7
42.8
#
_
40.4
39.3
41.2
42.9
39.6
37.1
31.8
32.8
32.6
32.5
35.4
33.7
33.5
39.7
39.6
39.5
38.3
36.9
38.3
22.1(*)
37.6
39.1
41.8
40.8
40.7
41.4
40.5
41.3
41.7
44.0
40.7
GAS PRODUCTION (Continued)
                                       % of CH4
                                    Thermo-   Meso-
                                    philic    philic
                                    64.5

                                    63.2

                                    62.6
                                    61.7

                                    63.4


                                    62.0

                                    61.0

                                    60.8


                                    60.8
                                    60.8
                                    61.3
                                    62.2

                                    63.7

                                    63.2


                                    61.8

                                    62.5

                                    62.8
                       59.6

                       61.6

                       60.5
                        59.8

                        59.6


                        60.0

                        60.0

                        59.8


                        59.5
                        59.3
                        59.5
                        60.4

                        60.1
                        58.9

                        62.4

                        60.5
                                Amount of Ofy - Liters
                                     Thermo   Meso-
                                     philic   philic
33.9

30.1

24.4
19.5


22.5

20.6

21.6


19.2
21.3
21.3
22.6

24.6
27.6

24.6

27.2
           26.8

           27.1

           26.0
           24.1


           25.7

           22.3

           19.6


           21.1
           23.5
           23.6
           22.3
           24.0

           25.3

           25.2
                                        4"2

-------
Table A-6.
GAS PRODUCTION (Continued)
      Gas Production - Liters
Date      Thermo-   Meso-
          philic    philic
            % of CH4
         Thermo-   Meso-
         philic    philic
Amount of CJfy - Liters
     Thermo   Meso-
     philic   philic
4/6
4/7
4/8
4/9
4/10
4/11
4/12
4/13
4/14
4/15
4/16
4/17
4/18
4/19
4/20
4/21
4/22
4/23
4/24
4/25
4/26
4/27
4/28
4/29
4/30
5/1
5/2
5/3
5/4
5/5
5/6
5/7
5/8
5/9
5/10
5/11
5/12
5/13
5/14
5/15
5/16
5/17
5/18
41.1
43.2
39.6
41.2
40.7
38.9
38.7
40.1
*
#
36.4
#
#
36.0
35.0
34.8
34.2
*
34.1
*
36.7
35.8
*
31.2
34.9
33.5
34.2
33.5
•8-
*
31.2
33.6
33.7
28.9
38.9
39.7
45.6
37.6
40.1
39.0
35.3
37.1
36.0
42.2
41.9
38.9
39.9
40.5
37.1
41.7
39.9
39.9
35.2
33.6
35.1
35.5
34.8
34.6
33.4
34.0
34.4
34.5
35.7
35.2
34.7
32.6
35.3
34.9
29.2
34.6
35.3
30.7
34.8
31.9
34.8
34.8
36.4
34.3
34.4
40.2
32.5
35.6
35.1
33.4
35.3
37.8
62.5
60.4

62.1


62.0

61.0
mfm
62.1
__
^
65.2
_
64.3
_
62.6
_
_
62.7
_
62.8
_
62.9
	
_
•*
_
60.5
_
62.1
_
—
63.2
_
63.0
_
62.2
-
-
62.3
59.9
63.0

60.8


60.6

60.7

59.8

_
62.5
—
62.2
_
60.5
_
_
60.4
«
60.3
_
61.8
_
_
60.5
_
60.7
_
60.4
_
_
61.1
_
60.7
_
60.8
-
—
61.3
25.7
23.9

25.3


24.9

w
mm
—
_
_
22.8
—
22.0
_
21.3
_
_
22.4
„
19.6
_
21.1
«
_
_
__
18.9
_
20.9
_
_
25.1
_
23.7
_
24.2
-
-
22.4
25.3
24.5

24.6

_
24.2
—
21.4
_
21.0
_
[
21.6
_
21.1
_
20.9
_
_
21.0
i_
21.3
w
18.0
_
_
18.6
_
19.4
„
21.0
_
_
21.0
_
19.7
_
21.3
_
_
23.2
                                      43

-------
Table A-6.
Gas
Date

5/19
5/20
5/21
5/22
5/23
5/24
5/25
5/26
5/27
5/28
5/29
5/30
5/31
6/1
6/2
6/3
6/4
6/5
6/6
6/7
6/8
6/9
6/10
6/11
6/12/87
6/13
6/14
6/15
6/16
6/17
6/18
6/19
6/20
6/21
6/22
6/23
6/24
6/25
6/26
6/27
6/28
6/29
6/30

Production
GAS
- Liters
Thermo- Meso-
philic
34.3
31.9
31.9
32.9
32.4
34.8
33.1
33.5
39.4
43.5
44.2
47.3
43.4
44.4
42.5
40.4
38.9
40.4
39.2
36.8
37.1
35.0
35.8
39.1
39.1
44.7
46.1
44.2
45.6
44.4
45.3
48.4
48.3
45.4
40.6
*
#
#
*
#
•H-
#
39.8
philic
37 3
«J / • ~J
35.2
34.9
36.8
34.9
34.6
33.6
33.5
39.1
36.6
46.8
47.4
43.7
42.6
42.5
38.4
35.4
37.6
38.0
39.8
39.3
36.9
39.1
42.4
42.4
44.0
50.6
45.5
48.7
43.4
41.6
42.5
44.9
44.0
43.1
42.4
41.6
40.0
40.5
40.8
42.2
39.8
39.8
GAS PRODUCTION (Continued)

            % of CH4        Amount of City - Liters
         Thermo-   Meso-         Thermo   Meso-
         philic    philic        philic   philic
         62.8

         62.5

         62.2


         61.2

         62.6


         62.5

         63.7

         64.0


         63.7

         63.9
         63.6

         64.4

         63.6


         62.1

         61.6

         62.1


         62.5
61.1

61.1

61.1


61.3

60.8


61.7

63.1

63.2


62.7

63.4
63.6

63.5

61.9


62.2

61.8

62.1


62.6
20.0
20.6
21.6
24.1
27.7
27.7
25.7
25.8
23.6
22.9
28.1
28.6
30.8
25.2
17.1
17.3
21.5
22.5
21.1
23.9
28.5
26.3
24.2
23.8
24.6
24.8
28.9
27.6
26.3
26.8
25.7
25.2
20.5
24.9

-------
Table A-6.
Gas
Date

7/1
Hi
7/3
7/4
7/5
7/6
111
7/8
7/9
7/10
7/11
7/12
7/13
7/14
7/15
7/16
7/17
7/18
7/19
7/20
7/21
7/22
7/23
7/24
7/25
7/26
7/27
7/28
7/29
7/30
8/1/87
8/2
8/3
8/4
8/5
8/6
8/7
8/8
8/9
8/10
8/11
8/12
8/13
»
Production
Thermo-
philic
45.1
44.5
46.0
49.8
48.9
49.6
48.6
47.2
46.2
45.6
49.0
49.9
48.6
47.7
44.8
46.6
47.0
49.3
49.5
49.1
50.5
49.5
51.7
51.3
47.7
52.5
51.2
47.9
49.2
50.4
51.3
53.1
48.9
48.1
48.3
49.9
50.8
53.4
58.1
54.4
52.1
53.1
54.4
GA:
- Liters
Meso-
philic
42.1
42.8
44.7
47.4
43.8
45.7
45.0
45.2
46.2
45.3
48.0
48.8
48.9
48.8
48.3
47.4
47.6
48.3
53.4
51.7
50.8
50.0
50.2
51.0
51.2
53.6
46.8
49.5
48.9
49.4
51.7
52.7
50.8
50.2
49.5
58.7
54.7
51.1
54.0
56.7
53.1
56.3
54.4
GAS PRODUCTION (Continued)

           % of CH4
        Thermo-   Meso-
        philic    philic
        63.3

        64.7


        65.2


        65.2



        64.9


        64.8

        65.5

        65.5


        65.2

        63.9

        64.7
        64.8
        63.9

        64.5
63.0

63.9


65.1


64.8



64.8


64.9

65.0

65.0


64.5

62.7

64.9
64.0
62.6

64.2
         Amount of City - Liters
              Thermo   Meso-
              philic   philic
28.5

29.8


32.3


30.1



31.5


30.2

32.3

32.2


33.7

30.5

33.1
32.7
36.1

31.5
26.5

28.6


29.8


29.9



31.7


30.8

31.4

33.6


32.4

32.1

30.4
31.6
37.4

32.6
62.6
63.6
63.0
61.08
62.6
61.7
31.2
33.9
34.3
35.8
32.0
35.0
        62.75
61.1
34.1
33.2
           45

-------
Table A-6.
GAS PRODUCTION (Continued)
      Gas Production - Liters
Date      Thermo-   Meso-
          philic    philic
              % of
           Thermo-   Meso-
           philic    philic
Amount of City - Liters
     Thermo   Meso-
     philic   philic
8/14
8/15
8/16
8/17
8/18
8/19
8/20
8/21
8/22
8/23
55.3
57.8
56.1
56.4
49.9
61.5
60.9
59.25
62.75
63.95
53.4
54.9
58.1
60.75
54.9
60.9
64.5
62.75
62.5
61.45

63.0
—
62.2
_
64.3
_
61.4
-
63.0

61.8
•••
60.5
—
62.1
_
60.2
-
61.6
^
36.4
_
35.1
_
39.5
_
36.4
-
40.3
_
33.9
-
36.6
-
37.8
-
37.8
-
37.85
 *Gas Meter Malfunction
                                        46

-------
Table A-7.
             DIGESTED SLUDGE SOLIDS - PERCENT
Date
         Total
Thermophilic   Mesophilic
                               1.4
                               1.4
         Volatile
Thermophilic   Mesophilic
12/9/86
12/16
12/23
12/29
1/5/87
1/12
1/19
1/26
2/2
2/9
2/16
2/23
3/2
3/9
3/16
3/22
3/29
4/3
4/11
4/19
4/25
4/27
5/3
5/4
5/12
5/17
5/25
5/31
6/7
6/14
6/21
6/27
7/5
7/9
7/12
7/16
7/19
7/23
7/26
7/30
8/2
8/6
8/9
8/13
1.39
1.5
1.5
1.69
1.56
1.5
1.65
1.63
1.73
1.8
1.8
1.88
1.89
1.91
1.98
1.92
1.79
1.91
1.96
1.84
1.91
1.92
1.89
1.91
1.85
1.99
1.86
2.01
2.05
2.23
2.29
2.35
2.5
2.47
2.42
2.39
2.35
2.38
2.39
2.25
2.24
2.L5
2.05
2.01
                               1.35
                               1.45
                               1.4
                               1.3
                               1.4
                               1.5
                                 58
                                 60
                                 65
                                 65
                                 71
                                 65
                                 76
                                 69
                                 67
                                 68
                                 78
                                 78
                                 84
                                 82
                                 82
                                 89
                                 82
                                 89
                                 84
                                 02
                                 02
                                 05
                                 08
                                 26
                                 26
                                 17
                                 21
                                 32
                                 29
                               2.14
                               2.21
                               2.11
                               2.19
                               2.15
                               2.05
                               1.92
67.2
70.0
69.8
72.4
72.5
72.6
72.6
72.6
72.5
73.7
70.7
71.53
72.5
72.6
71.12
73.3
73.2
71.78
71.27
72.45
72.45
72.8
71.95
71.13
72.04
71.16
70.85
69.71
68.65
67.47
67.96
67.85
67.43
66.59
67.10
67.05
67.18
66.59
66.60
66.20
66.52
66.07
66.75
67.02
68
68.5
68.
69.
69.4
68.8
68.2
69.0
6y.9
63.0
66.7
68.0
66.6
68.3
67.4
67.6
67.3
66.36
65.35
67.49
66.45
67.3
65.47
66.03
68.12
67.50
65.80
65.54
66.84
66.41
66.05
67.87
67.82
67.77
68.98
64.55
67.66
67.38
67.68
67.07
68.31
65.80
66.33
65.92
                                       47

-------
Table A-7.     DIGESTED SLUDGE SOLIDS - PERCENT (Continued)

                   Total                              Volatile
Date      Thermophilic   MesophilJc          Thermophilic   Mesophilic


8/,15            2.03           1.95                66.54        66.96
8/19            2.03           1.99                67.76        66.24
8/23            1.96           1.96                69.56        69.13
                                        48

-------
Table A-8.
              DIGESTED SLUDGE COD - mg/1
Date
           Total
Therraophilic   Mesophilic
           Soluble
Therraophilic     Mesophilic
12/9/86
12/15
12/22
12/30
1/6/87
1/13
1/19
1/26
2/2
2/9
2/16
2/24
3/3
3/12
3/17
3/26
3/31
4/7
4/14
4/21
4/28
5/5
5/12
5/19
5/26
6/2
6/9
6/16
6/23
6/30
111
7/9
7/14
7/16
7/21
7/23
7/30
8/4
8/7
8/11
8/13
8/23
14,652.8
19,311.2
20,498.4
18,931.2
19,584.4
17,766.7
22,131.2
19,698.
22,367.5
22,750.
23,522.4
24,384.
24,140.2
26,118.4
24,083.0
24,288.0
22,816.0
23,359.0
17,856.0
22,080.0
23,865.6
22,221.0
22,041.6
22,848.0
21,888.0
23,312.0
22,337.0
23,584.0
27,244.0
26,864.0
25,834.0
27,980.0
27,784.0
28,205.0
28,518.0
26,827.0
26,085.0
25,723.0
25,280.0
23,813.0
22,943.0
24,898.0
15,520.4
19,215.6
15,912.
16,518.4
16,292.2
14,318.4
17,196.2
16,954.
18,432.5
20,202.5
22,161.6
22,848.
20,338.6
21,827.5
21,693.0
19,184.0
20,435.2
19,890.0
18,240.0
20,609.0
21,515.2
21,700.0
22,435.2
21,504.0
22,656.0
'2,748.0
23,973.6
21.824.0
22,148.0
25,716.0
24,710.0
24,605.0
24,012.0
24,860.0
27,440.0
23,620.0
23,990.0
25,723.0
24,531.0
23,038.0
21,979.0
25,085.0
                                                      .4
                                                      .2
                                       1311.
                                       1269.6
                                       1445.2
                                       2500.
                                       2962.9
                                       2954.9
                                       3359.2
                                       3488.8
                                       3878.0
                                       4267.0
                                       3810.2
                                       2841.6
                                       1938.8
                                       2873.0
                                       3014.9
                                       3238.
                                       2698.
                                       2386.8
                                       1881.6
                                       2024.0
                                       2097.3
                                       1946.3
                                       2,597.8
                                       2,265.6
                                       2,112.0
                                       2,068.0
                                       2,106.6
                                       2,604.8
                                       2,195.2
                                       1,816.4
                                       2,003.0
                                       2,087.7
                                       2,079.2
                                       2,097.3
                                       2,195.2
                                       2,138.4
                                       2,284.8
                                       2,199.0
                                       2,172.0
                                       2,090.0
                                       2,005.0
                                       2,621.0
                    401.
                    351.8
                    351.9
                    356.4
                    422.2
                    350.2
                    814.1
                    399.8
                    368.6
                    377.6
                    396.6
                    376.32
                    380.2
                    402.9
                    419.2
                    563,
                    726.
                    469,
                    522,
                    699.
                    716.0
                    624.96
                    755.71
                    568.32
                    837.12
                    624.16
                    709.61
                    823.68
                    595.8
                    608.0
                    599.0
                    589.0
                    596.2
                    578.6
.2
.1
.2
.2
.2
                                                                   678.2
                                                                   544.3
                                                                   624.5
                                                                   768.0
                                                                   734.0
                                                                   658.0
                                                                   559.0
                                                                   607.0
                                       49

-------
Table A-9.
                         DIGESTED SLUDGE NITROGEN - rag/1
Date
    Ammonia
Thermophilic
                       Mesophilic
        Organic
Therraophilic  Mesophilic
12/A/86
12/9
12/15
12/22
12/26
12/30
1/6/87
1/13
1/19
1/29
2/2
2/9
2/16
2/24
3/2
3/9
3/17
3/24
3/31
4/7
4/14
4/21
4/28
5/5
5/12
5/19
5/26
6/2
6/9
6/18
6/23
6/30
7/7
7/9
7/14
7/17
7/21
7/24
7/31
728
672
644
840
756
728
812
742
700
644
798
826
812
733.6
764.4
865.2
851.2
849.8
851.2
849.8
843.0
840.0
834.4
812.0
831.0
834.4
824.6
884.8
854.0
861.0
851.2
777.0
844.2
882.0
935.2
931.0
945.0
929.6
911.4
700
770
* I \J
616
784
700
672
700
602
615
532
644
686
714
680.4
702.8
697.2
668.0
728.0
728.0
725.2
734
758.8
736.4
739.2
737.8
756.0
763.0
795.2
772.8
737.8
716.8
658.0
690.2
728.0
728.0
741.8
754.6
735.0
753.2
672
560
588
308
672
588
538
644
700
658
518
568.4
697.2
658.
511
591
572.6
558.6
595
554
582.4
652.4
621.6
610.8
760.2
760.2
690.2
719.6
778.7
796.6
833.0
929.6
938.0
886.2
933.8
939.4
904.4
580
406
616
476
728
588
630
617 .
840
756
602
758
798.
873.
716.8
757.4
758.8
754.6
736.4
741.0
753.2
779.8
828.8
817.6
764.4
756.0
851.2
868.1
887.6
870.8
928.2
978.6
971.6
966.0
1037.4
1085.0
1006.6
                                                     897.4
                                                          988.4

-------
Table A-10.         DIGESTED SLUDGE OIL & GREASE (mg/1)

Date                          Thermophilic             Mesophilic

                                   2255                   1935

iM/fl7                             220°                   1625
I/6/87                             6035                   2290
1//13                               1726                   1333
1/J9                               2955                   2200
1/26                               4505                   3035
2/2                                   _                   29U
2/9                                   -                   1225
2/16                               3259                   2356
2/25                               4311.5                2479
3/3                                3368                   2735
3/11                                2434                   1864.5
3/17                                2403                   1925.5
3/24                                2483.5                1770.0
3/31                                1770.3                1782.5
4/7                                 2359.5                1769.0
4/14                                2290.7                2041.0
4/21                                2712.2                2196.7
4/28                                2518.3                2109.4
5/5                                 2525.9                2070.4
5/12                                2059.4                1585.8
5/19                                2627.3                2051.6
5/26                                2531.7                2161.1
6/2                                 2430.5                2191.2
6/9                                 2383.9                 2191.7
6/10                                2683.0                 2066.0
6/23                                3002.9                 2274.0
7/2                                3283.0                 2762.6
7/7                                3396.0                 2767.1
7/9                                3333.3                 2702.3
7/14                               3537.7                 2403.2
7/16                               3385.1                 2655.0
7/21                               3589.0                 3041.3
7/23                               3093.0                 2338.3
7/28                                2918.6                 2273.5
7/30                                2761.8                 2188.8
8/4                                 3125.1                 2484.2
8/6         (Soluble)                 178                      38
8/11                                2853.0                 2482.0
8/13                                2453.0                 2095.0
8/23                                2535.0                 2130.0
                                       51

-------
Table A-ll.
DIGESTED SLUDGE CARBOHYDRATE
            mg/1
       Total
Date
6/17/87
6/23/87
6/29/87
7/6/87
7/9/87
7/14/87
7/17/87
7/21/87
7/24/87
7/28/87
7/31/87
8/4/87
8/7/87
T
3150
3068
2650
3240
3360
2770
2950
2300
2710
2950
3140
2520
2360
M
2182
1870
2060
2230
2160
1890
2200
1890
2200
2080
1950
2020
1710
OWJ.U 1
T
143
95
113
127
69
168
68
88
133
106
90
57
101
L/-LW
M
124
49
69
68
34
78
51
27
57
56
60
30
53
                                        •52

-------
Table A-12.         MEAN CAPILLARY  SUCTION TIME  (SEC)
                            (Unconditioned Sample)

Date          Temp.  (°C)            Thermophilic          Mesophillic

3/14/87           -                    611.8*                524.2*
3/15              -                    466.3*                A75.5*
3/21              -                    417.3*                A57.6*
3/22              -                    463.2*                398.5*
3/29              -                    423.2*                389.0*
4/5              -                    405.5*                491.4*
4/19              -                    463.2                 402.7
4/23            21                     512.1                 425.0
4/30              -                    496.7                 416.9
 5/3            25                     464.7                 351.8
 5/5            23.5                   480.7                 372.9
 5/6            23.5                   490.6                 387.9
 5/7            25                     432.8                 405.5
 5/8            21.5                   482.2                 411.6
 5/11           24.5                   467.3                 426.7
 5/12           25                     495.37                409.4
 5/13           23.5                   465.7                 469.2
 5/20           25                     638.7                 493.0
 5/21           24.5                   632.5                 593.2
 5/22           24.5                   589.9                 494.6
 5/23           24.5                   485.0                 405.5
 5/24           24.5                   534.9                 417.8
 5/25           24.0                   496.8                 414.2
 5/26           24.0                   533.2                 402.8
 5/27           24.5                   516.3                 405.1
 5/28           24.5                   527.1                 377.1
 5/29           25                     504.9                 399.9
 5/3i           26                     506.6                411.4
 6/1            26                     506.3                  376.9
 6/2            25                     533.6                 419.1
 6/3            24                      596.8                 414.9
 6/4            23.5                    557.5                 434.5
 6/5            23.5                    587.2                 439.8
 6/8            25                     574.4                 464.1
 6/9            26                     535.0                 403.3
 6/10           24                     722.6                 472.2
 6/11            26                     561.9                 403.3
 6/12            24                     597.0                 423.9
 6/15            25 5                   618-°                 421'2
                 24.5                   781.5                 5223

  6/17            23'5                   Sfi'fi                 38*4
  A/IR            9S                     566.6                 jyo.H
  Inc.            25 5                   533.8                 386.0
  6/22            26                     510.4                 384.!
                                         53

-------
Table A-12.         MEAN CAPILLARY SUCTION TIME (SEC) (continued)
                            (Unconditioned Sample)
Date          Temn  fOp\           m
                 P> <• L)           Thermophilic          Mesophillic
6/23            27
6/24            26  5                   501'5                 381'5
6/25            9A                     549'5                 410.0
6/26            25  5                   606'6                 42°'3
6/29/87         26                     ™\'l                 443i
6/30            ?ft  «;                   453<4                 344'8
7/1             £1                   444'4                 318'1
7/2             ?A't                   454'4                 327'4
                26-5                   A58.4                 316.3
  ,              25                      527.6                 333.5
7/5             49                      415.2
7/5             35                        _                   300.8
7/5             25                      533.9                 377.9
7/6             25                      571.2                 407.3
7/9             22                      562.4                 379.1
7/11            25                      548.0                 387.0
7/13            22                      548.2                 339.4
7/15            25                      535.2                 395.7
7/16            25                      653.7                 404.7
7/18                                   684.0                 417.0
7/20            25                      623.5                 362.6
7/22            25                      642.2                 338.4
7/23            25                      742.7                 405.1
7/25            25                      771.0                 448.0
7/27            25                      814.7                 485.0
7/29            25                      782.0                 397.2
7/30            25                      694.2             •    383.2
8/1             25                      732.0                 451.0
8/3             25                      672.3                 369.3
8/5             25                      600.6                 321.4
8/6             25                      647.0                 385.4
8/8             25                      655.0                 388.0
8/10            25                      595.3                 358.0
8/12            25                      644.7                 366.4
8/13            25                      600.2                 444.6
8/15            25                      648.0                 385.0
8/21            25                      627.0                 362.0
8/23            25                      595.0                 387.0
* Temperature not measured

-------
Table A-13.   CAPILLARY SUCTION TIME TESTS WITH CONDITIONERS ADDED
I

Date
3/15/87




3/21/87







3/29/87





4/5/87






•"eCl36H20
Added
( g/D
0
1
2
3
4
0
1
1
1
1
1
0
0
0
3
4
5
6
7
0
4
-4
4
4
4
4
Ca(OH)2
Added
( 8/D
0
0
0
0
0
0
0
0.5
1.0
1.5
2.0
0.5
2.0
0
0
0
0
0
0
0
0
0.5
1.0
1.5
2.0
3.0
Mesophillic
Cup Size
(cm)
1.8
1.8
1.8
1.8
1.8
1.8
1.8
1.8
'1.8
1.8
1.8
1.8
1.8
1.8
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0

pH
7.15
6.6
6.5
6.2
6.1
7.35
6.95
7.45
7.90
8.50
8.65
8.15
8.9
7.4
6.4
6.0
5.65
5.35
5.30
7.5
6.8
7.1
7.4
7.55
7.75
8.5
CST
(sec)
475.5
288.8
74.4
22.5
15.7
398.5
142.7
, 155.4
230.0
166.4
237.6
429.6
407.3
389.0
90.1
44.9
30.8
25.5
22.6
491.4
40.8
42.2
30.8
33.8
30.0
78.7
Thermophilic

PH
7.4
6.9
6.5
6.3
6.1
7.6
7.1
7.45
8.05
8.40
8.60
8.40
8.90
7.75
6.3
6.25
5.9
5.8
5.3
8.0
6.65
7.1
7.25
7.40
7.65
8.3
CST
(sec)
466.3
392.8
135.9
57.6
16.2
463.2
271.3
223.2
348.6
317.4
261.8
431.1
378.4
423.2
342.3
62.6
30.3
23.4
19.3
405.5
78.3
91.9
69.0
85.2
141.5
203.2
7/8/87


7/15/87





3
4
5
4
5
6
4
10.4
8.9
0
0
0
0
0
0
0
0
0
1.0
1.0
1.0
1.0
1.0
1.0
1.8
1.0
1.0
6.6
6.75
6.75
6.7
6.4
6.15
6.7
—
4.3
335.9
110.3
61.7
19.4
32.0
19.4
10.8
-
18.0
6.9
7.05
6.6
6.55
6.4
6.15
6.55
4.3
-
1291.2
685.4
362.6
1020.4
493.8
79.6
149.2
17.5
-
                                      55

-------
Table A-13.   CAPILLARY SUCTION TIME TESTS WITH CONDITIONERS ADDED

                                 (Continued)
Date
7/22/87
 7/29/87
 8/5/87
          Ca(OH.)2
 Added     Added   Cup Size
 (  8/D   ( 8/1)     (cm)
                      Mesophillic
                              CST
                      pH     (sec)
Thermophilic
         CST
pH      (sec)
4
4
5
6
9.05
10.4
6
5
4
4
9.0
10.8
4
4
5
6
7
8.95
10.45
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1.0
1.8
1.0
1.0
1.0
ti.o
1.0
1.0
1.0
1.8
1.0
1.0
1.0
1.8
1.0
1.0
1.0
1.0
1.0
6.3
6.3
6.1
5.9
4.3
-
6.0
6.15
6.4
6.4
4.3
-
6.35
6.35
6.2
6.0
5.8
4.3
-
99.3
31.1
34.7
24.1
18.8
-
25.9
40.2
76.0
16.1
17.5
-
53.7
11.1
25.2
18.0
16.1
16.6
-
6.5
6.5
6.3
6.15

4.3
6.2
6.35
6.5
6.5
_
4.3
6.5
6.5
6.4
6.2
6.0
-
4.3
933.5
140.2
594.3
169.2

16.7
186.7
663.3
1039.8
161.6
—
18.3
908.0
154.0
193.0
49.6
25.3
-
17.8
 8/12/87
 4
 5
 6
 7
 9.2
10.0
0
0
0
0
0
0
1.0
1.0
1.0
1.0
1.0
1.0
6.2
6.0
5.8
5.6
4.3

40.0
21.0
20.8
16.3
15.9

6.5
6.3
6.1
5.9
-
4.3
           49.5
          119.5
           34.3
           15.8
                                                                         16.4
                                        56

-------