EPA-670/2-74-056
JULY 1974
Environmental Protection Technology Series
                                                                ISlll
                                             National Environmental Research Center
                                               Office of Research and Development
                                              U.S. Environmental Protection Agency
                                                          Cincinnati, Ohio 45268

-------
                                                          EPA-670/2-74-056
                                                          July 1974
                    DEVELOPMENT OF ON-SHORE TREATMENT SYSTEM

                FOR SEWAGE  FROM WATERCRAFT WASTE RETENTION  SYSTEM
                                        By

                                  James H. Robins
                                  Arthur C. Green
                                  FMC Corporation
                            Advanced Products Division
                            San Jose, California  95108
                              Contract No. 68-32-0220
                            Program Element No. 1BB038
                                  Project Officer

                                 David J. Cesareo
                  Industrial Waste Treatment Research  Laboratory
                             Edison, New Jersey  08817
                         Environmental  Protection
                         Region V, Library
                         230 South Dearborn  Street
                         Chicago, Illinois   6060«f
                      NATIONAL ENVIRONMENTAL RESEARCH  CENTER
                        OFFICE OF RESEARCH AND DEVELOPMENT
                       U.S.  ENVIRONMENTAL PROTECTION AGENCY
                              CINCINNATI, OHIO  45268
For sale by the Superintendent of Documents, U.S. Government
      Printing Office, Washington, D.C. 20402

-------
                             REVIEW NOTICE
The National Environmental Research Center — Cincinnati has reviewed this
report and approved its publication.  Approval does not signify that the
contents necessarily reflect the views and policies of the U.S. Environ-
mental Protection Agency, nor does mention of trade names or commercial
products constitute endorsement or recommendation for use.
                                    ii
                       ENVIRONMENTAL FROTSCTICIT ACUKCY

-------
                                FOREWORD
Man and his environment must be protected from the adverse effects of
pesticides, radiation, noise and other forms of pollution, and the
unwise management of solid waste.  Efforts to protect the environment
require a focus that recognizes the interplay between the components of
our physical environment - air, water, and land.  The National  Environ-
mental Research Centers provide this multidisciplinary focus through
programs engaged in

     •  studies on the effects of environmental contaminants on man and
        the biosphere, and

     •  a search for ways to prevent contamination and to recycle val-
        uable resources.

The appreciable growth of recreational activity in this country has
presented an additional burden on our land and water resources.  Rec-
reational watercraft waste is a minor fraction of the waste flow from
land based sources.  Their presence, however, in our environment con-
tributes to the total ecological problem we face today and demands that
we develop waste treatment solutions that are technically and economic-
ally feasible.

                                         A.W . Breidenbach,  Ph.D.
                                         Director
                                         National Environmental
                                         Research Center, Cincinnati
                                  111

-------
                               ABSTRACT
A two-phase program developed and demonstrated a new method for on-shore
treatment of sewage from recreational watercraft.   Phase I characterized
wastes and chemical additives associated with recirculating/retention
systems.  Statistical analysis determined probable ranges of waste char-
acteristics as a function of watercraft type and location.  Typical
wastes had suspended solids and biochemical oxygen demand of 2000 mg/1.
Respirometer studies evaluated toxicity of additives to activated sludge.
Treatability of chemical/sewage mixtures was determined from pilot-scale
activated sludge plant operations.   Cell yield coefficients were
calculated.  Photomicrographs recorded physical changes to activated
sludge.  Concentrations greater than 20 mg/1 zinc  or 120 mg/1 formalde-
hyde caused adverse effects to the activated sludge process.   Phase II
field tested full-scale physical-chemical treatment equipment operating
on watercraft wastes.  Average removal efficiencies for suspended
solids, biochemical and chemical oxygen demand, phosphate, and zinc were
greated than 90 percent.  Effluent coliform was less than 10 MPN/1QQ ml.
Discharge solids were nonodorous and innocuous.  Postchlorination
increased total-nitrogen removal from 30 to 70 percent.  Operating costs
for wastes having approximately 2QQO mg/1 SS and BOD^ were $6.2/Kl
($23-5/1000 gal.).   Auxiliary treatment cost for zinc removal and
postchlorination was $1.5/K1 ($5-7/1000 gal.).

This report was submitted in fulfillment of Contract No. 68-32-0220 by
FMC Corporation, Advanced Products Division, San Jose, California, under
the sponsorship of the Environmental Protection Agency.  Work was
completed as of December 1973.
                                  IV

-------
                                CONTENTS
Foreword
Abstract
List of Figures
List of Tables
Acknowledgments
 iii
  iv
  vi
viii
   x
Section                                                             Page
   I        Conclusions                                              1
  II        Recommendations                                          3
 III        Introduction                                             4
  IV        Characteristics of Watercraft Wastes                     8
   V        Characteristics of Chemical Additives                   15
  VI        Treatability of Sewage Containing Chemical Additives    27
 VII        Activated Sludge Treatment of Chemical Wastes           37
VIII        Process Description                                     50
  IX        Laboratory Process Studies                              54
   X        Process Field Testing                                   63
  XI        Process Evaluation                                      70
 XII        Discussion                                              78
XIII        References                                              81
 XIV        Appendices                                              83

-------
                                 FIGURES
No.                                                               Page

 1    Rate of Change in Mixed Liquor Dissolved Oxygen Content as
      a Function of Formaldehyde Chemical Additive Concentration   19

 2    Rate of Change in Mixed Liquor Dissolved Oxygen Content as
      a Function of Zinc Sulfate Chemical Additive Concentration   20

 3    Rate of Change in Mixed Liquor Dissolved Oxygen Content as
      a Function of Quaternary Ammonium Chemical Additive Con-
      centration                                                   21

 4A   Effect of Chemical Additive Concentration on"Activated
      Sludge Respiration Rate                                      24

 4B   Effect of Chemical Additive Concentration on Activated
      Sludge Respiration Rate                                      25

 5    Relative Sewage Treatability as a Function of Chemical
      Additive and Sewage Suspended Solids                         31

 6    Relative Sewage Treatability as a Function of Percent
      Chemical Waste Composition                                   34

 7    Effluent Characteristics after Slug-feed of 380 mg/1
      Formaldehyde                                                 43

 8    Photomicrographs of Activated Sludge Exposed to Increased
      Zinc Concentrations                                          44

 9    Photomicrographs of Activated Sludge Exposed to Increased
      Formaldehyde Concentrations                                  45

10    Schematic Drawing of FMC Waste Treatment System              51

11    Photograph Identifying Major Components of the FMC Waste
      Treatment System, Model 50-2000                              52

                                    vi

-------
                          FIGURES - Continued
No.

12    Demonstration Trailer Housing Treatment Equipment Located
      at Lake Mead, Nevada                                         67
                                  vii

-------
                                  TABLES


No.                                                                 Page

 1    Analysis of Recreational Watercraft Waste Samples              10

 2    Statistical Results of Waste Characterization Data             12

 3    Marina Survey Data                                             13

 4    Characteristics of Chemical Toilet Additives                   16

 5    Respiration Rate Data for Activated Sludge Mixed Liquor
      Containing Chemical Toilet Additives                           22

 6    Toxicity Data and Dilution Requirements for Chemical
      Toilet Additives                                               23

 7    Characteristics of Sanitary Sewage Containing Chemical
      Toilet Additives                                               28

 8    Treatability Data as a Function of Sewage Suspended Solids
      and Chemical Toilet Additives                                  30

 9    Treatability Data as a Function of Sewage Composition and
      Chemical Toilet Additives                                      33

10    Comparison of Chemically Treated Feed Sewages for Activated
      Sludge Pilot Plant Studies                                     39

11    Results of Activated Sludge Treatment of Sewages Containing
      Chemically Treated Wastes                                      41

12    Cell Yield Characteristics for Activated Sludge Treatment
      of Chemically Treated Sewages                                  47

13    Zinc Disposition in Activated Sludge Process                   48

14    Full-Scale Process Results on Chemically Treated Sewages       55
                                   Vlll

-------
                          TABLES - Continued


No.                                                                 Page

15    Effect of Formaldehyde on Process Treatment Results            58

16    Effluent Chlorination Data                                     61

17    Summary of Marina Survey Results                               64

18    Results of Lake Mead Testing                                   72

19    Results of Lake Mead Testing with Zinc Removal and Post-
      chlofination Treatment                                         73

20    Characteristics of Solid Filter Cake                           74

21    Chemical and Power Consumption and Cost Data                   76
                                   xx

-------
                            ACKNOWLEDGMENTS
The authors wish to convey their appreciation to Mr. David J. Cesareo,
Project Officer, and Mr. William J. Librizzi, Chief, Watercraft Wastes
Branch, U.S. Environmental Protection Agency for their continual guidance
throughout the performance of this contract.

The authors express their gratitude to the 46 harbormasters, fuel dock
operators, and marina managers that participated in the waste sample
collection program and marina surveys.

We thank the manufacturers of chemical toilet additives that furnished
confidential information regarding the composition of their products.
This information added significant value to this report.

Special acknowledgment is due Mr. Temple A. Reynolds, Assistant
Superintendent, Mr. William Stephenson, Chief of Park Maintenance, and
all park personnel of Lake Mead National Recreational Area, National
Park Service, for their cooperation and assistance during the demon-
stration phase of this contract.

-------
                              SECTION I

                             CONCLUSIONS
The following conculsions are based on empirical results and character-
istic facts determined during this research.

     1.   Wastes from retention systems onboard recreational watercraft
         have suspended solids (SS) and biochemical oxygen demand (BODs)
         of approximately 2000 mg/1, coliform populations of 10^ MPN/100
         ml, deep coloring,  and various amounts of chemical pollutants.

     2.   Chemical additives  used in recirculating/retention waste sys-
         tems employ surfactants, perfumes,  dyes, and bacteriostats of
         zinc,  formaldehyde, and quaternary ammonium compounds.  These
         additives have varying effects on the aerobic respiration
         rate of activated sludge.  With increased concentration, zinc
         additives are highly toxic while formaldehyde and quaternary
         ammonium additives  are initially biodegradable but become toxic
         at higher concentrations.

     3.   Biological treatability of wastewater from recreational water-
         craft is a function of chemical additive concentration and
         waste  characteristics.  Wastewaters having more than 20 mg/1
         zinc or 120 mg/1 formaldehyde (from chemical additives) cause
         significant disruption of the activated sludge process with
         loss of removal efficiency.

     4.   Comparative studies with a laboratory respirometer and a
         pilot-scale activated sludge plant show similar results in the
         determination of relative toxicity and treatability of sewages
         containing specific chemical additives.

     5.   The demonstrated physical-chemical process provides a high
         level  of treatment  of recreational watercraft wastes with
         greater than 90 percent removal of SS,  BOD5,  chemical oxygen
         demand (COD), and phosphate.   Effluent coliform is less than
         10 MPN/100 ml.  Solid filter cake discharge is nonodorous and
         innocuous.

-------
6.  Auxiliary treatment of process effluent can attain greater
    than 90 percent total zinc removal while postclorination
    demonstrates the ability to significantly increase total-
    nitrogen removal.

7.  Complete physical-chemical treatment of watercraft wastes
    having approximately 2000 mg/1 SS and 1000 mg/1 BODs costs
    $6.2/kl ($23.5/1000 gal).  Chemical cost for standard treat-
    ment is $3.9/kl  ($14.9/1000 gal)  and power cost is $0.7/kl
    ($2.7/1000 gal).   Auxiliary treatment cost for zinc removal
    and postchlorination is $1.5/kl ($5.7/1000 gal).

-------
                              SECTION II

                            RECOMMENDATIONS
This program was concerned only with a portion of the chemical-
contaminated wastewaters requiring adequate treatment by federal law.
Major problems exist with conventional biological treatment of industrial
wastewaters and land recreational wastes.  Proposed federal guidelines
will prohibit wastewater discharges to publicly owned treatment works
that may induce a treatment process upset and subsequent loss of treat-
ment efficiency.  Best practical water pollution control technology is
required to meet the growing demands for a cleaner environment.  To
achieve this objective, the following recommendations are made:

     1.  Test and evaluate the demonstrated system as a pretreatment
         method for removing zinc and other heavy metals, oils and
         grease, and suspended solids from industrial wastewaters.

     2.  Determine the applicability and effectiveness of the
         demonstrated system as an unattended roadside sanitary
         treatment facility in recreational areas and along highways.

     3.  Test and evaluate the demonstrated system for on-shore complete
         treatment of saltwater sanitary sewage and bilgewater from
         commercial and military vessels.

     4.  Design, develop, and evaluate new treatment methods capable of
         efficient, economical removal of nitrogen compounds from waste-
         water.

     5.  Conduct a research program to establish standard procedures
         utilizing respirometer equipment to determine the relative
         treatability and toxicity of polluted wastewaters.

-------
                              SECTION III

                             INTRODUCTION
NATURE OF PROBLEM

Historically, the nation's waterways have been the recipients of  man's
wastes from both land and watercraft sources.  While active Government
programs are providing facilities to treat wastewaters from our cities
and industries, marine vessels of all types have in the past continued
to dump raw sewage.

The harmful effects of discharges of untreated sewage into the waterways
include (1) virus and bacteria that can infect people, directly or
through marine life, with various diseases;  (2) excessive oxygen de-
mands that reduce the life supporting oxygen concentration of the water;
(3) upset of the aquatic environment by blocking sunlight with suspend-
ed or floating solids, as well as sludge layers on the bottom; and (4)
the aesthetic insult created by floating sewage solids.  The mobility
of marine vessels allows discharge of sewage wastes almost anywhere and
any time.   This creates a specific hazard to public health, recreational
and port facilities, and commercial fishing industries.  In 1970 the
Federal Government started action to control the discharge of sewage
from vessels.  The Water Quality Improvement Act of 1970 called for
prohibition of discharge of untreated or inadequately treated sewage
into or upon the navigable waters of the United States.  The U.S.
Environmental Protection Agency (EPA) was delegated the responsibility
of establishing effluent standards for marine sanitation devices, while
the U.S. Coast Guard was given the responsibility of promulgating the
implementation regulations.  In June 1972, the EPA proposed a no-
discharge standard2, which replaced the initial proposed standards
requiring the equivalent of secondary treatment.  In March 1974, the
Coast Guard proposed certification procedures and design and con-
struction requirements for marine sanitation devices .  These regu-
lations will become effective for new vessels after 2 years from
promulgation and after 5 years for existing vessels.

Compliance with a no-discharge standard can be achieved on large vessels
via several approaches, including treatment and reuse or recirculation

-------
of the effluent for flushwater, liquid evaporation and solids inciner-
ation, or by total destruction by injection into a boiler system.  For
smaller, recreational watercraft, these approaches are not feasible or
economical.  Sanitary wastes must be retained onboard in recirculating/
retention waste systems.  Chemical additives containing bacteriostatic
agents and perfumes are commonly used in conjunction with these systems
to control the sewage odor.  On-shore pumpout facilities are employed
to remove these wastes from the individual watercraft.

The availability of adequate treatment facilities for these wastes is
a major problem in most recreational areas.  Pumpout facilities are
often many miles from the collection system of municipal treatment
plants.  The treatability of these wastes by conventional biological
methods is often variable, because of toxic effects from certain
chemical additives.  Without sufficient dilution, these wastes may
cause significant upset and loss of removal efficiency to the activated
sludge process.  After heavy weekend recreational activity, shock
loadings of these wastes have seriously disrupted small municipal treat-
ment plants.^

Advanced physical-chemical processes have been developed as an alterna-
tive to conventional wastewater treatment methods.  Employing no bio-
logical activity, physical-chemical systems are capable of a high degree
of treatment, independent of the presence of toxic materials.  With
variable design capacities and automatic operation, this approach is
ideally suited for application to the treatment of recreational water-
craft wastes.

In 1968 the Advanced Products Division, FMC Corporation, San Jose,
California, began development of a physical-chemical waste treatment
system.  The process includes disinfection, chemical clarification,
adsorption by activated carbon, and filtration.  Chemicals employed
are a bactericide, flocculant, activated carbon, and filter aid.  The
system is automatically controlled on a demand basis with instantaneous
on-off operation.  Construction materials have been designed to with-
stand a saltwater marine environment.
OBJECTIVE

The objective of this program was to develop and demonstrate a new,
effective system for on-shore complete treatment of sewage pumped from
recreational watercraft waste retention systems.  Complete treatment
was defined as 90 percent removal of biochemical oxygen demand (BODs),
suspended solids (SS), nitrogen, phosphorous, and disinfection as
required to meet local, state, and federal regulations.  To achieve
this objective efficiently, the program was divided into two distinct

-------
and separate phases.  Phase I involved the characterization of water-
craft wastes and verification that the proposed system was capable
of complete treatment.   Phase II involved the field demonstration of
a full-scale treatment unit operating on actual watercraft waste pump-
age.  This program was to be completed over a 12-month period.
SCOPE OF WORK

The scope of Phase I included the following tasks:

     1.  Waste Characterization.   Samples of waste were collected from
         recreational watercraft having retention/recirculating sani-
         tary systems.  Each sample was analyzed in the laboratory for
         chemical and biological parameters.  Chemical content, flow
         volume, and variations throughout a boating season were
         established for watercraft wastes over a broad geographical
         region.

     2.  Description of Chemical Additives.  A survey of manufacturers
         and suppliers of chemical additives was performed to determine
         the types and composition of chemicals used in conjunction
         with retention/recirculating systems.  A survey of marinas
         established the types and use of the most common additives.
         Laboratory studies determined the relative effects of common
         chemical additives on activated sludge.

     3.  Biological Treatment of Watercraft Wastes.  Respirometer
         studies determined the relative effects of chemically treated
         wastes on activated sludge.   A pilot-scale activated sludge
         plant was operated on various chemical/domestic waste mixtures.
         Treatability data and toxic effects were determined.

     4.  Process Studies.  Simulated watercraft wastes containing
         various chemical additives were processed in the laboratory
         and on full-scale demonstration equipment to determine the
         capability of complete treatment.  Process modifications
         were made to achieve this objective.

The scope of work in Phase II involved the following activities:

     1.  Test Site Selection.  Freshwater and saltwater locations were
         surveyed for consideration as a demonstration site.  Final
         selection was determined on the basis of the number and types
         of boats, flow volume of boat waste pumpage, and length of
         boating season.

-------
2.  Process Field Testing.   A full-scale treatment unit was demon-
    strated for 8 weeks at Lake Mead,  Nevada.   All watercraft
    waste pumpage at two marinas was processed.  Samples were
    collected daily for analysis, and operating data were recorded.

3.  Process Evaluation.  Removal efficiencies were calculated from
    laboratory analytical data.  Cost of operation was determined
    from chemical and power consumptions.  Maintenance requirements
    were listed.   Characteristics and disposal of solid filter cake
    were established.

-------
                              SECTION IV

                 CHARACTERISTICS OF WATERCRAFT WASTES
WASTE SAMPLING

A program was designed to sample wastes from the basic types of
recreational watercraft located in freshwater and saltwater in various
regions of California and Nevada.  Between March and July 1973, 65
waste samples were collected at 8 freshwater and 8 saltwater
marina locations.  Forty-six samples were taken from individual boats,
while 19 composite samples were collected from waste storage tanks con-
taining boat pumpage.

Sampling was done at fuel docks, pumpout facilities, and at individual
moorings.  With the owner's permission, the entire undiluted contents
of the boat holding tank or recirculating toilet were transferred to a
suitable container by means of a positive displacement diaphragm pump.
No tank flush water was included in the sample.  After noting the total
volume, the waste sample was gently mixed by hand or electric stirrer.
Larger samples (greater than 100 liters) were mixed by recirculation
through the diaphragm pump.  A 2-liter portion of the blended sample
was transferred to a sterile polyethylene bottle and immediately packed
in ice for preservation at 4°C.  Composite pumpout wastes in storage
tanks were first agitated by recirculation through the diaphragm pump,
then transferred to sample containers.  Total waste volume was estimated
from tank dimensions and waste level.

All samples were transported in ice chests to the Environmental
Engineering Laboratories, FMC Corporation, Santa Clara, California, for
immediate setup or analysis.  The normal sample holding period was 5
hours, with a maximum of 14 hours for samples from Southern California.
RESULTS

The source of each waste sample was characterized by the watercraft type
and length, waste system capacity, and pumpout frequency.  Each waste
sample was described by total volume, approximate age, chemical additive

-------
used, and type of flush water  (freshwater or saltwater).  Sample
analysis included 15 characteristic parameters describing wastewater.
All analytical procedures were done in accordance with  the EPA's
Methods for Chemical Analysis of Water and Wastes^.  Table 1 gives the
descriptive details and analytical results of seven waste samples.
Because of the quantity of tabular information, the data describing all
65 waste samples are given in Appendix A.  The results  of analyses for
22 heavy metal elements are given in Appendix B.

Analytical data were treated statistically to interpret the results of
the sample collection program.  Six boat categories were established
for comparison.  Samples were collected on the basis of individual and
composite sources, fresh and saltwater locations, and boat type.  A
computer program automatically sorted data according to category and
determined maximum, minimum, and average values for each parameter.
In addition, a weighted average was determined using the total waste
volume at the sample source as the weighting factor.  A value range, 95
percent confident to contain the true parameter value,  was also
calculated.  The six boat sample categories listed below were statis-
tically treated in this manner.

     1.  Powerboats and Sailboats

     2.  Houseboats

     3.  Powerboats, Sailboats, and Houseboats

     4.  Powerboats and Sailboats on Lake Mead

     5.  Houseboats on Freshwater

     6.  Houseboats on Saltwater

Results of individual samples  (those taken directly from a boat) were
used to determine the statistical results of all categories except
number 4.   Only composite samples (those taken from waste-storage tanks
of pumpout facilities)  were used to describe Lake Mead  watercraft
wastes.  (Composite waste samples are diluted 50 to 100 percent with
flushwater used to rinse the waste retention system.)

Houseboats are defined as mobile live-aboard watercraft with pontoon
flotation structure.  Most houseboats sampled in this program were
public rentals that carry an average of 3 people for 4  days.  It was
noted that the characteristics and volume of waste pumpage from rental
houseboats varied significantly as a function of the weather,  boating
season, and crew complement.

-------
















*
w
1-5
CM.

iH
•§
M

0)
4J
iH
CO
O
O.
I
U



i-H
rt
3
TJ

Indlv


•3
-3
•H
1
M


3
TJ
•H
•H
•a
H


i-H

3
TJ
•H
•H

M

S

CO
O



U






ft
H
0)
u






CO
i
CM
CM
CO


CO
r-.
i
CM
CM
CO




CO
r«.
CM
CN
1
CO



CO
CM
CM
1
CO



CO

1
CM
CM
1
CO





CO
1

CO


CO
r-

00
o
1
CO





CD
JJ
S
•H
JJ
U
CD
3
"8
rt
rH
CO


O

M


0
60
01

Q
C
CO


^
(S
c
0
•rl
CO
m
2


O
bO
0)
•H
c
n)
CO


3,
0}

Q
1






•3
1

rH

rt



CU


J







a
o
•H
«
u
o









00





r-
vo"






^





VO






vO








m








"






|
»

•H
M







JJ
"•^
W




w
i-H
CO






JJ
CO
CO




CO
CO





JJ
rH
rt
CO






JJ
rH
rt
CO





CO


*






CU
ft

M
(U
4J
rt
3



CM


£
0)
g
PL,

01
JJ
•rl
en
o
S
U



CO
"*

Power


00
CO
ower
0,


CO
CO


CU
g
fn


_
vD

m
to
3
S

<0
JJ
•rl
CO
O



tj


X
JJ
00
c
1
ft
H

CO
1
U
1
CO

&
<

m
H
1
0}
c-

^
m
H



a
1
0
3
o-




1
E-i





irt
1
f-i
§
6
i

<4H
2
W.
m
H

01
4J
•rl
w
o
CU


u



0)

•H
4J
T3
"3
U
iH
g








O
rH




1
1
1






O
tn
CO




fx.
1—1






CM








0
CO




m
CM
CO







Ct
rH
0

a
w
ffi
3






•g


rH



CO
rt

ON



CO
"iu

m
CM



CO
a-
TJ
in




CO
x
-o
m





JA
oi

^



CO
X
rt
T3

*







M

2
CO
rt
3:

























































CO

CO

1
•J

CO







0

CM
00




o

CM






8
CM




O
ej\
CM





O
CO
r-.







0







O
O
01





^
rH



s






o

-------
Table 2 gives the statistical results describing the characteristics of
undiluted-waste pumpage from retention/recirculating systems onboard
recreational powerboats and sailboats  (Category 1).  The results for
all six categories are given in Appendix C.  Specific details of the
number of samples in each category are included.

To characterize the recreational boating community and its facilities,
each marina or marine location that supplied waste samples was surveyed
for the following characteristics: number of boats, boat types and aver-
age lengths, percentage of boats with onboard sanitary waste systems,
waste holding capacity, existence of pumpout facilities, disposition
of pumpout wastes, and common brands of chemical toilet additives used
or sold.  Table 3 gives these results for 16 marine locations sampled
during this waste characterization program.
DISCUSSION

Results of the waste characterization indicated that pumpage from
recreational watercraft is highly concentrated, deeply colored, and
contains variable amounts of toxic materials.  Typical waste pumpage
from recreational watercraft had the following characteristic ranges:

                  SS           1400 to 3400 mg/1

                  TOC          1500 to 2900 mg/1

                  BOD5         1700 to 3500 mg/1

                  COD          4400 to 7900 mg/1

                  T-N          1600 to 2000 mg/1
                                 ?      10
                  Coliform     10  to 10   MPN/100 ml

                  Zinc         25 to 250 mg/1

With nearly exclusive use of freshwater makeup in watercraft toilet
systems, the geographical location of the boat in freshwater or salt-
water had no significant effect on the wastewater characteristics. House-
boat wastes were generally more concentrated than wastes from powerboats
and sailboats.  Season variations most directly affected the volume and
characteristics of wastes from rental houseboats.   A rental houseboat
with 10 passengers operating in Lake Shasta,  California for 7 days yield-
ed 340 1 (90 gal)  of wastewater having 20,000 mg/1 SS and 15,000 mg/1
BOD56.


                                  11

-------
r— i

15
H
H
W
H
EH
CO
cs

 0)
W 4)*a
14 3 "s
in S
.0
O
"S 0

4 -H
U >
0^
fits

u
I 9

*•<






It
5 j


Ij
1-





2-

K I.
« 01
li
s 2
• o.



§§
CO




o
QO
m

0


8
QO








00
00*


s
o








l^v
rH
9



w

O 0
01 CM
(M




0
m

s


rH
CO








S



O








^

f


w


O VO


&
g










                                                                                                                    o

                                                                                                                    ff
                                                                                                                        i  S
                                                          12

-------
IS
H




|
•a
B

CD
£
B'S
f( 03
•a
a) -a
i "
6


,

4J O
•r-l 4J

U 41
co a
(C
4J £
O, >r-

, »
D. cr
co <;


•g
o
CM
C
O
•o
CO -r-l
^,5



O O
1^. r-l







-S
O O
CN r^
CM





_
(fl CM
to
t

I i
5 o
CM £



1-1
XI 0
« ON
4-1
o i-^ £
u ^ a
(0X0
00 O to
0) CO M
> 01
CN


•o
0
o
<0
s


1
u

01 CO
II




o
M OO
U) CO
a™ §"
• 4-1
5° S
u • >
w a- o



1
U
1
fl)
t4

1
s
1 U
!»

m K
1 -H





01
CO 4J
JH U



r»» CN







ff-S
i— ' O
OO OO






CO ^
1

u


o

3
siz
S-H ^J-
CQ a*
Ballena Bay Y
1150 Ballena
Alameda, CA








1
U
1
§
s
in
i






S
za



in CD
A







^
O 00
§•"





?
w
^
a-
Is
C

<:
00
•H 0
W 4J CM
•H 01 CT\

M 4J «*;
o w O
4-> O
CO O 00
O CO -r-l
rJ Q
• o c
Ctl rH CO




§
g
1
4J

CO
1

k






I
CO
CO S"

01 CO
II


1

CO Q
'£ 1 3
n] (0 CM
S -1 0*
cO H
i-l O -
W ,O O
M ^ ao
a 01
•H
0 Q
& O
* o" C
B CM CO
CO



OO
35
^

rH
0
O
1
to a
H U
* CO
1 CP





0)
CO
« £
111 -H



0 O








o m
o r-»






CO
CO
jj1
CJ
Is



a*
O 0)
"S "
as g_
s is
O Q O
m
cfl 0 (0
doc
<0 m co
Q CM Q



i— t I
0 §
5,6
H c
M O

So
u
Vg
§1
CP O
in nJ
1 h





I
CO 4-1
01 -H
SH O



in m







^

o &
CO

m




cO
CO
£
O)
CM en


CM
w O
o
£ G
QJ
CO >, *
cO ^
S rS
3 O 0)
cO cO eO
CMC
•H O r-l
)-i 03 M
O


O
I-l
1
^
33

1
6
§
51
in
i





w
« £•
(U >H
>-l U



O 0
CM •-!







^
o m
o r«-





„
rt CN
CO
iT 01
0> CO
gg
CM 33



o
.0
1 0
W rt O
T) 3 CO
| Channel Islan
3900 Pelican
Oxnard, CA 9

r-i

1
4J
CO
W

I
cO
3
a-
in
'






0
§,$.


6-s
O 0
m r-i







3-2
§b
r^






CO
J1
O CM

01

2
o
o
< o
en
£ gS
Peninsula Yac
Peninsula Dri
[ Oxnard, CA 9
CN







6
I
4J
•a
£
•0
i




1L
H 'a
,31
£££


ff-S
§o
CO







H
m o
OO O






CN
1
O)
W
1


™  5
O r-t
32 CQ -
International
21112 Ventura
Woodland Hill

>-*

f
c
•o
§
4->

CJ
g
o
3:
m
i





01
CO
„ £.
U -H



0
o o>







fi~2
0 0
r-4 O






cn
a>
I



a)
r-l
C Q 0
-H CM
CO H O^
S a)
| Village West
6650 Embarcad
| Stockton, CA

rH






1
U
1
(0
<
m
i

cO
U
•H 4J
t>o C
O (8
rH rH
O CX
^Q 4J
QJ m
2P E
crj 4-1
-i CM jj



o o
CO CM







^
o o
O QO





l-l
1
0)
en
la



rt
C
H
QJ
Rainbow Bridg
Lake Powell
Utah

*-i






e
1
CO
3
cr
in
'




|^
H 'a
'^ T^
.3 S
^S^i



P*. O
in m







s^
O r*.
m





CJ
1
01
0]
JO
m




0

j-i «— i «i
^ g .
>, CO C
CO 0)
30'is
SB.-O

rH

                                           13

-------
The largest volumes of waste pumpage occurred during July and August.
Approximately 85 percent of all boat pumpout activity occurred Friday
through Monday.   The average onboard waste-retention time was 17 days.

The most commonly used chemical toilet additives had ingredients of
zinc sulfate or formaldehyde.  The range of zinc concentrations found
in individual waste samples was 0 to 3530 mg/1,  with an average of 46
mg/1.   Samples were not analyzed for formaldehyde.

Heavy metal analysis of 64 waste samples showed no presence of arsenic,
beryllium, molybdenum, or selenium.  Mercury was detected in six
samples at a concentration ranging from 6 to 9 mg/1.  Relatively low
concentrations (less than 0.2 mg/1) of cadmium,  chromium, copper, lead,
manganese, nickel, and silver were found in most samples.  Significantly
high concentrations of aluminum, calcium, magnesium, tin, potassium,
iron,  and sodium were determined.  Toxic levels of certain metals were
indicated by individual samples having concentrations as high as 104
mg/1 cadmium, 79 mg/1 lead, 3540 mg/1 zinc, and 13.5 mg/1 copper.
                                   14

-------
                          SECTION V

              CHARACTERISTICS OF CHEMICAL ADDITIVES
CHEMICAL COMPOSITION

A survey of manufacturers and suppliers was conducted to determine the
types and composition of chemicals used in conjunction with waste
retention/recirculating systems.  Nine companies were selected from a
list of all known manufacturers of bacteriostatic chemicals as repre-
senting the market and the spectrum of chemicals used in recreational
waste systems.  A letter of transmittal and a questionnaire were sent
to each company requesting their cooperation in supplying general
characteristics of their product, which included recommended dosages,
safety cautions, generic chemical composition, acidity-alkalinity, and
heavy metal content.   The results of this survey are given in Table 4.

The three basic types of active ingredients employed in chemical toilet
additives are (1) zinc salts, (2) formalin or paraformaldehyde, and (3)
quaternary ammonium compounds.  Dense dyes and perfumes are normally
present to mask offending color and reodorize the sewage contents.
Surfactants and water softeners are used to help solubilize the waste
solids.  Liquid additives are mostly aqueous solutions with small
amounts of alcohol.   All additives are toxic if ingested and harmful
to skin and eyes.  Careful handling is required, especially with those
containing formaldehyde.

Since the time of this survey, several new additives have been marketed
to replace older ones, especially those containing zinc salts.  The
list of active ingredients has expanded to include substituted phenols,
available chlorine, and so-called "concentrated bacterial enzymes."
*Formalin is a 37-percent aqueous solution of formaldehyde with 7 to
15 percent methanol.
                                   15

-------
U
H
S
w
ffi
u
o
H
EH
W
H
ff!
H
U
 0)
r-l

•8
EH



10
>1 rH
> fl)
CO 4-1
CU 0)
x s

















in
4-1
C
01
•H
•a
M Oi
01 K
43 Oi
•P C
O H




O

fc
f\
4J
C
CU
•H
0) Tl
> 0)
••H lH
4-1 Ol
0 C
< H
0)
Cn
C
33 en
ft oi
^
o
rH
o
u


E
o
fc,
CO
O) -^
D! r —
CO \
in E
rH
cd
u
-H
e cu
a TI
43 O
CJ O





0)
13

01
•a
c

4J
o
CO
14H
Vl
3
10

cu

P
tH
V4
01
ft

h.
rH
o
43
o
u
rH
<


QJ
•a

_r]
0)

rH
cfl
e
Vl
o
[L.

*
in
ro


CO
1
"°

0)
3
rH
m
•o
•H
3
0*
• H
^
in

rH
1
in


o
T
cu
•H
2
3
U


fi
















(1)
^1
•o

h.
01
g

MH
Vl
01
CM


O)
T!

^
CU
Tl
rH
cfl
6

O
<4H
CO
in
cO
CM


00
1
ID
C
eu
01
Vl

^
01
•a
g
CM


01

ro


0
CN



CO
4-1
CO


£
01
•c
4-1
-C
cfl
4-1
U
CO
14H

CN
1



VO
CN







C
N






CU

•a


c
cO
O
tfl
14H
Vl
3
m

v
cu


4H
Vl

CM


0)
•P 0)
CO -P
>4H CO
rH V)
3 Tl

43
U O
C C
•H O
N S

tfP
j~-
CO


r-
1
^

CU
3
rH

Vl
01
Tl
I



in

rH


ro
ro





0)
C
0
Z






0)

•o


c
cfl
4-1
0
(0
UH
VI
3


n
0)


14H
Vl
01
tn
|
•H
C
o

P
r^2

£X|
Vl
CO
c
Vl
01

CO
3
Oi


CO
1
"°
1
0)
3
rH
pa
0)
rH
3
C
cO
Vl
o


[-^

rH


CO
ro


















































4-1
rH
CO
M





C
0)
01
Vl
U

















3
CO
Tl

§






0)

T!

4-1
C
S
U
cO
<4H
Vl
3
CO

k.
0)


14H
Vl
01
CM


01
Tl

43
0)
Tl
rH
CO
cj

O

CO
Vl
CO



CO
1


01
3
rH
CO
Vl
01
Tl
O
CM


in

rH


r^
in



S
CO
•a

g






01

T3

4JV
C

U
CO

Vi
3
10

*,
0)


MH
Vl
01
CM


0)
Tl

43
CU
•a
rH
CO


O
MH
CO
Vl
CO
CM


CO
1


cu
3
rH
CQ
Vl
cu
•o
o
CM


in

rH


rH
^





0)
c


























0)
>,
a





H 4-1
CO rH
C CO
Vl {/I
01
•P g
tO 3


Q
rfP S
o e
rH r£


00
1


Q)
3
rH
pa
•a
H
3
D1
•rH
^


CN

i— i


m
H
CO
0)
4-1
in
in
Vl
cO
•H
c
cO
10
C
O
itenti
cu
Vl
tTi
C
•H
4-1
CO
rH
3
O
Vl
•H
O
ID
Vl

O
0)
N
in

Tl
C
fO
c
0
• H
4-1
CO
O
, — 1
ft
ft
CO
01
43
4-1

0
4-1

Ol
a
•H
Tl
Vl
o
u
o
ca


Vl
to


in
rH
cu
01
rH

O)
cn
CO
cn
o
T!

•a
0)
Tl
c
o
C
G
o
O
cu













T
8
to
43
4-1
g
dP
0

•o
to
01
Tl
43
01
T)
rH
g
O
14H
r#j
f"-«
ro
10

^
"71
•H
43
S
fc
C
•rH
rH
tO


o
HH

J>^
o
rH
ft
§
01

cn
01

•H
4-1
•H
T3
T)
cfl

Ol
Oi
4-1
1
01

^
43
CU
•a
rH

C

O
UH

•O
•H
3
W
•H











•
Vl
3
press
•a
cu
u
3
Tl
0)
Vl
4-1
CO
C
-rH
CO
V|
0
rji
C
• H
4-1
tO
!H
C
0)
o
c
o
u

>1
43
•a
0)
Vl
ft
0)
Vl
ft

Vl
0)
1,
rH
O
ft

0)
Tl

43
0)
Tl
1— 1

E

o
m
CO

cn
•H

CU
Tl

43
CU
•O
rH
ffl

Vi
o
m
CO
Vl
CO
CM
                                                              16

-------
CHEMICAL USAGE

Survey results from 16 marine locations indicated that the most com-
monly used chemical additives contain zinc salts and formaldehyde.
Chemical Additive Codes 26 and 40 were used 85 percent of the time.
This popularity was explained by satisfaction with the product or by
compliance with the recommendations of the chemical toilet manufacturer.
Most of these manufacturers market their own additives.  Boat owners
stated that recommended dosages were satisfactory for short periods of
time, but that additional charges were required to suppress odor after
5 to 10 days.
TOXICITY TO ACTIVATED SLUDGE

The primary function of chemical toilet additives is as a bacteriostat,
which suppresses normal respiration and growth of bacteria.  The result
is less gas production by the bacteria and a reduction or control of
unpleasant odors.  This method can be effective when holding sanitary
wastes, although much concern exists over how these wastes are later
disposed of and their effect on biological wastewater treatment sys-
tems.  The same bacteriostatic effect can reduce the level of biologi-
cal treatment and result in sub-quality process effluent.

An experimental program was conducted to measure the relative toxicity
of various chemical additives to unacclimated activated sludge aerated
for 30 hours without feed.   A Princeton Aqua-Science Aerobic Treat-
ability Unit (Model EG-300),* measuring dissolved oxygen (DO), was used
to determine a reference respiration rate of activated sludge as well
as respiration rates of this sludge in the presence of varying con-
centrations of chemical additive.  A comparison of these rates gave a
qualitative determination of the biodegradability or toxicity of the
specific chemical additive.

Seven different additives representing the three basic types of bac-
teriostatic compounds were characterized at five different chemical
concentrations.  Activated sludge was obtained from the FMC Environ-
mental Engineering Laboratories, who operate a package treatment plant
(Chicago Pump,  Model SL-144) at 190 kl/day (50,000 gal/day) on munici-
pal sewage from Santa Clara, California.
*Princeton Aqua-Science, 789, Jersey Avenue, New Brunswick, New Jersey.

                                   17

-------
A standard operating procedure was followed for all determinations with
the respirometer.  This included constant temperature, aeration, agita-
tion, and mixed liquor volatile suspended solids (MLVSS).   Fresh mixed
liquor was aerated without feed for a minimum of 30 hours to achieve
the endogenous state.  After adjusting the volatile suspended solids
concentration by diluting with water, a 600-ml portion of diluted mixed
liquor was placed in the reaction vessel, agitated, and aerated for
20 minutes and adjusted to 25°C +_ 1°C.  At the end of aeration, a zero-
time dissolved oxygen reading was taken,  followed by additional read-
ings as a function of time, until 30 minutes had passed.  Since the
rate of disappearance of dissolved oxygen from the activated sludge
mixed liquor is equal to the dissolved oxygen uptake rate of microbial
respiration, the slope of the straight line portion of a plot of dis-
solved oxygen versus time was defined as  the reference respiration
rate (k ).  Using the same procedure, a relative respiration rate (k)
was determined with each additive at its  recommended dosage and four
other concentrations.

Figures 1, 2, and 3 are plots of dissolved oxygen content versus time
for mixed liquors containing various concentrations of formaldehyde,
zinc, and quaternary ammonium chemical additives.   Table 5 gives a
summary of all respiration rate data from studies on seven chemical
additives.  It was interpreted that relative respiration rates  (k)
less than the corresponding reference respiration rate  (k )  indicated
deleterious effects by the presence of the chemical additive.
Similarly, k values greater than kr indicated that the specific ad-
ditive was biodegradable and supplied nutrients to the sludge, result-
ing in increased microbial respiration.   At the recommended dosage of
all except one additive tested, k values  were substantially less than
k  values.  Respiration rates increased as chemical additive concentra-
tion decreased.  At low concentrations of formaldehyde and quaternary
ammonium additives, the k values were greater than k , while both
zinc additives gave k values that only approached kr.  These results
indicated that zinc additives at all concentrations greater than 15 to
20 mg/1 exhibited a deleterious or toxic  effect on activated sludge.
Formaldehyde and quaternary ammonium additives exerted a toxicity at
high concentrations but were biodegradable at lower concentrations.

For comparison, the percent of relative respiration rate (k/k  x 100)
calculated from rate data for each chemical additive concentration.
Values greater than 100 indicated the biodegradability of the chemical
additive while values less than 100 indicated toxicity.  Values of
100 indicated that the relative respiration rate (k) equaled the re-
ference respiration rate (kr),  and that the additive had no effect on
the respiration rate of the activated sludge.

                                 18

-------
                                                            4-1
                                                             O

                                                             a
                                                             o
                                                            •H
                                                            -P
                                                             u

                                                             3
                                                             w
                                                             tc

                                                             -P
                                                             fi
                                                             0)
                                                             4->

                                                             0
                                                             u

                                                             c
                                                             (U
                                                             en
                                                             >i  C
                                                             X   0
                                                             13   to
                                                             0)   >-i
                                                             >  -p
                                                             H   C
                                                             0   0)
                                                             to   o
                                                             w   fi
                                                             •H   0
                                                             •o   o

                                                             J-l   0)
                                                             o   >
                                                             P  -H
                                                             tJ1 -p
                                                             •H  -H
T3  to
 0)
 X  H
•H  (0
 g  U
    •H
 C  g
•H  QJ

 0)  U
 Cn
 C  0)
 ffl  T3
                                                                 0)
                                                             O  rH
                                                                 to
                                                             (U   g
                                                             -P   M
                                                             (0   O
           -P
           •H
           3
           O1
           •H
           •H
           g
           -P
           ft)
           •a

           OJ
           -P
           to
           C
           0
           •H
           -P
           (0
           0)
           O

           0)
           M
           OJ
                                                                       •P
                                                                        G
                                                                        0)   •
                                                                        en  0)
                                                                        0)  >
                                                                        M  -H
                                                                        a -P
                                                                        (U  -H
                                                                        M  13
                                                                           -a
                                                                       O  rt)
           C  <0
           ofl  U
              •H
           W  g
               0)
           W fi
           •P  O
           0
           H  O
           ft  C
                                                             
-------
                                                                                    3
                                                                                    w

                                                                                    u
                                                                                    c
                                                                                    •H
                                                                                    N

                                                                                    M-l
                                                                                    O

                                                                                    C
                                                                                    0
                                                                                    •H
                                                                                    4J
                                                                                    O
                                                                                    W
                                                                                    (0
                                                                                    C
                                                                                    0)
                                                                                    4J

                                                                                    O
                                                                                    u
                                                                                     cu
                                                                                     01

                                                                                     X
                                                                                     O

                                                                                    -o
                                                                                     0
                                                                                     en
                                                                                     en
                                                                                    -H
                                                                                    TD
                                                                                        C
                                                                                     M  O
                                                                                     0  -H
                                                                                     3  4J
                                                                                     tj1 rt3
                                                                                    •H  M
                                                                                    rH  4J
                                                                                        C
                                                                                    T3  (U
                                                                                     0)  O
                                                                                        c
                                                                                        O
                                                                                        u
-H
 B
Wdd  '
                   N3SAXO Q3.KIOSSIQ
                                                                                     C   0)
                                                                                    •H   >
                                                                                        •H
                                                                                     CU  4-)
                                                                                     tr -H
                                                                                     C  'O
                                                                                     (0  T)
                                                                                    £   fl
                                                                                     o
                                                                                        r—)
                                                                                    M-l   (0
                                                                                     O   U
                                                                                        •H
                                                                                     CD   g
                                                                                    4-1   0)
                                                                                     (0  X
                                                                                    PS  t5
                                                                                    CM

                                                                                     CD
            0


           5
           •H
                                                                                                O1
                                                                                               •H
                                                                                               T3
                                                                                                0)

                                                                                               •H
            0
           M-l

            (0
           4J
            (fl
           T)

            CU
           4J
            Ifl
                                                                                                0
                                                                                               •H
                                                                                               4-1
                                                                                                Ifl
            cn
            0)
            M

            CU
            o
            c
            CU

            0)
           M-l
            OJ
            C
            CU
            w
            0)

            a cu
            0)  >

               4J
            O  -H
           fa  (0
               u
            W  -H
           -P  S
            O  CU

           CM  O
                                                                                     Cn
                                                                                    •H
                                  20

-------
                                                          O O
                                                     •H .H O t-
                                                   < H CJ O H
O
i-t
               O

               00
                       I

                       O
 I
o
 I
o
 I
o
                       _ CO
                                                                            •8
                                                                           _GO
                                                                             i-l
                                                                           _vO  2
                                                                             •1  O
                                                                           _O
                      o
                      o
                 Wdd  '1N31NOO N30AXO
                                                                                     |Q

                                                                                     M
                                                                                     0)
                                                                                     4J
                                           u
                                          • H

                                           0)
                                          •g

                                           0
                                           c
                                                                                              •H

                                                                                               (8
                                                                                              •O
                                                                                               0)
                                                                                               X
                                                                                              •rl
                                                                                               e
c
OJ
R
X
0
•o c
0) O
> -H
rH +J
0 ID
Ul Vl
Ul -P
•H C
•O Q)
0
H C
0 0
3 0
o<
•H Q)
H >
•H
•S3
X «O
-H -O
e 10
C i-l
•H ro
O
0) -H
S1 S
C W
m x
£ 0
IH

5
fO
T3
0)

(0
^

c
0
•H
+J
rO

•H
Pi
U)
(1)


0)
U

0)
tt
M-l

-------
   Table 5.   RESPIRATION  RATE DATA  FOP ACTIVATED SLUDGE MIXED LIQUOR
              CONTAINING CHEMICAL TOILET ADDITIVES
Chemical
Codea


40
40
40
40
40
83
83
83
83
33
33
33
33
33
33
33
96
96
96
96
20
20
20
20
38
38
38
38
26
26
26
26
26
Chemical
Concentration
(mq/1)
h
4,500
3,000
1,500
150
15
11,250
3,750
375
37.5
4,500
3,000b
1,500
750
750
150
15
13,500,
D
4,500
450
45
11,760,
3,920
392
39.2
5,100
1,700
170
17
8,820
4,420
442
44.2
22.1
MLSS/MLVSS
(mg/l/mg/1)


1250/1010
1250/1010
1390/1140
1390/1140
1390/1140
2055/1715
2060/1920
2060/1920
2060/1920
2390/1955
2670/2240
2670/2240
2670/2240
2670/2240
2670/2240
2390/1955
2055/1715
2055/1715
2055/1715
2055/1715
1485/1255
1485/1255
1485/1255
1485/1255
1300/1095
1300/1095
1300/1095
1300/1095
1115/915
1260/1030
1260/1030
1260/1030
1115/915
Reference
Rate, k
(mg/l/min)

0.366
0.366
0.379
0.379
0.379
0.236
0.242
0.242
0.242
0.343
0.344
0.344
0.344
0.344
0.344
0.343
0.204
0.204
0.204
0.204
0.261
0.26L
0.26L
0.26L
0.243
0.243
0.243
0.243
0.408
0.430
0.430
0.430
0.408
Relative
Rate , k
(mg/l^min)

0.049
0.050
0.067
0.325
0.404
0.063
0.131
0.401
0.252
0.053
0.070
0.084
0.102
0.096
0.154
0.315
0.025
0.029
0.180
0.400
0.098
0.317
0.428
0.527
0.021
0.019
0.185
0.327
0.027
0.041
0.148
0.355
0.346
Percent
Relative Rate,
k/k x 100

13.4
13.7
17.7
85.8
106.6
26.7
54.1
165.7
104.1
15.5
20.3
24.4
29.7
27.9
44.8
91.8
12.3
14.2
88.2
196.1
37.5
121.5
164.0
201.9
8.6
7.8
76.1
134.6
6.6
9.5
34.4
82.6
84.8
a  Chemical  code number legend:  Formaldehyde Type  =  20, 40, 83, 96.
   Zinc  Salt Type = 26,33.  Quaternary Ammonium Type  =  38.

b  Recommended dosage concentration.
                                        22

-------
Figures 4A and 4B show plots of the percent of relative respiration
rate versus chemical additive concentration.  The maximum nontoxic
chemical additive concentration was estimated from these graphs at the
point where each plot intersected the 100 percent relative rate value.
The dilution factor required to lower the chemical additive concen-
tration from its recommended dosage to this maximum nontoxic con-
centration was calculated with the result given in Table 6.
      Table 6.  TOXICITY DATA AND DILUTION REQUIREMENTS FOR
                CHEMICAL TOILET ADDITIVES
Chemical
Code
26
33
20
40
83
96
38
Active
Ingredient
Zinc Sulfate
Zinc Sulfate
Formaldehyde
Formaldehyde
Formaldehyde
Formaldehyde
Quaternary
Ammonium Salt
Recommended
Dosage
(mg/1)
4420
1500
3920
4500
3750
4500
1700
Maximum
Non- Toxic
Cone (mg/1)
20
15
5900
55
2350
400
110
Dilution
Factor
220
100
1.0
80
1.6
11
15
 Maximum chemical additive concentration that does not adversely
 affect the respiration rate of activated sludge.

 Volume dilution required of chemical additive at its recommended
 dosage to eliminate any adverse effect on respiration rate of
 activated sludge.
DISCUSSION

Respirometer data indicated a low tolerance of zinc by activated sludge.
The maximum zinc additive concentrations that had no adverse effect
                                  23

-------
                                                                               0)
                                                                               4-)
                                                                               C
                                                                               0
                                                                               •H
                                                                               -P
                                                                               Ifl
                                                                               M
                                                                               • H

                                                                               ft
                                                                               Ul
                                                                               0)
                                                                               cu
                                                                               4-1
                                                                               fC
                                                                               >
                                                                               •H
                                                                               4J
                                                                               U
                                                                               rd

                                                                               C
                                                                               o


                                                                               §
                                                                               •H
                                                                               4-)
                                                                               fO
                                                                               !H
                                                                               •P
                                                                               C
                                                                               QJ
                                                                               U

                                                                               0
                                                                               0
                                                                               -H
                                                                               4-1
                                                                               •H
                                                                                (0
                                                                                U
                                                                               -H

                                                                                0)

                                                                                O
                                                                                u
                                                                                a)
                                                                               W
                                                                                0)
                                                                                M
                                                                                3
                                                                                &i
                                                                               •H
aiva KOiiwaidsaa
                        24

-------
     01
    •a
s
u
X
u

In
O
 n)
 u
•H

 H
                                                                                                              W
                                                                                                              en
                                                                                                              •H
                 3J.VH
                                           25

-------
on activated sludge respiration rate ranged from 15 to 20 mg/1.  Based
on the chemical content, the calculated zinc concentration was 5 to 7
mg/1.  This result agrees quite well with the reported maximum level
of 5.0 to 10 mg/1 zinc that will not produce an adverse effect on
activated sludge treatment efficiency ''.

Formaldehyde additives had varying effects on activated sludge.  Each
additive was biodegradable over a certain concentration range, and
within this range the percent of relative rate data went through a
maximum indicating a point of greatest nutrient value to the activated
sludge microorganisms.  These maximum values varied significantly.
The concentrations at which these additives began to have adverse
effects on respiration rate also varied significantly.  Chemical Code
40 showed toxic effects at 50 mg/1, while Chemical Code 20 was bio-
degradable at concentrations greater than 550 mg/1.  These results may
be explained by differences in the composition and/or the solubility
of additive ingredients.  Liquid additives employing formalin were
toxic at much lower concentrations than solid additives using para-
formaldehyde.   Methylene blue,  present in certain liquid additives
as a dye, will have a definite toxic effect on most bacteria.

A maximum concentration of 55 mg/1 of Chemical Code 40 had no adverse
effect on respiration rate.  The calculated formaldehyde concentration
was 20 mg/1.  This additive was 95 percent formalin with methyl blue,
perfumes, and surfactants.  The reported toxic concentration of
formaldehyde in domestic sewage is 135 to 175 mg/1-'- .   The significant
difference in these results suggests additional toxicity from in-
gredients other than formaldehyde.  On the other hand, in the presence
of sewage, formaldehyde may readily react with proteins resulting in a
lower free-formaldehyde concentration available to microorganisms.  In
this case, higher initial formaldehyde concentration is required in
the presence of sewage to produce the same toxic effect on activated
sludge.  The absolute accuracy of toxic concentrations determined in
this study is questionable because interpolation of values from
limited data results in a large probable error. Therefore, only
qualitative significance should be given to these results.

To avoid the toxic effects of specific additives, significant volume
dilution is required.  Ten liters of waste containing the recommended
dosage of zinc additive may require dilution with as much as 2200
liters of water or domestic sewage before eliminating its adverse
effect on activated sludge treatment efficiency.


                                  26

-------
                             SECTION VI

        TREATABILITY OF SEWAGE CONTAINING CHEMICAL ADDITIVES
Respirometer studies of activated sludge/sewage mixtures were made to
determine relative respiration rates as a function of sewage suspended
solids and chemical additive concentration.  Comparison of these rates
indicated the relative treatability of such sewages and the maximum
tolerable concentrations of zinc and formaldehyde that would not have
adverse effects on the activated sludge process.
RESPIROMETER STUDIES

Using fresh raw body wastes, several series of sewage samples were pre-
pared with a suspended solids range of 900 to 9000 mg/1.  Zinc, formal-
dehyde, and quaternary ammonium chemical additives were added at their
recommended concentrations to specific samples.  An undiluted sewage
sample having no chemicals served as a control.  Portions of each
sample were analyzed for various chemical and biological parameters.
This analysis was repeated after aging all samples at 25°C for 72
hours.

Activated sludge mixed liquor was aerated for 30 hours without feed to
establish its endogenous state.  The reference respiration rate (k )
of this mixed liquor was determined by procedures described in Section
V.  Mixtures of activated sludge and chemically treated sewage were
prepared to maintain a constant loading factor (mg/1 BODs//mg/l MLVSS)
for each series of sewage suspended solids.  After aeration for 20
minutes to saturate this mixture with dissolved oxygen, the rate of
change in mixed liquor dissolved oxygen content was measured as a
function of time, and a relative respiration rate (k) was determined
for each mixture.  For comparison of these data,  percent relative
respiration rate values (k/kr x 100) were calculated for each sewage
sample.

Table 7 gives the characteristics of sewage samples involved in this
study.  Sample 1 describes the original sewage sample with no chemical
additives.  Sample 2 describes that same sewage after 72 hours aging.
                                  27

-------
Table 7.  CHARACTERISTICS  OF SANITARY SEWAGE  CONTAINING  CHEMICAL
           TOILET ADDITIVES
Sample Number

Chemical Additive Type
Additive Code No.
Additive Cone, (gm/1)
Age of Waste (hrs)
SS (mg/1)
VSS (mg/1)
COD (mg/1)
BOD5 (mg/1)
TOC (mg/1)
SOC (mg/1)
T-N (mg/1)
pH
CONDUCTIVITY (MHO)
COLIFORM (MPN/100 ml)
1

Control
—
0
0
10,400
9,000
20,800
7,300
7,600
4,000
4,600
9.0
18,000
13 x 1010
2

Control
—
0
72
10,000
7,900
14,600
6,400
7,400
4,200
4,600
9.1
23,000
6 x 106
3
a
Zinc
26
4.4
72
12,900
9,100
24,100
7,200
7,400
3,500
4,500
7.4
16,500
6 x 106
4
a
Zinc
26
4.4
72
6,400
4,400
12,100
2,700
3,200
1,500
2,100
7.4
8,600
2 x 105
5
b
Form.
40
1.5
72
10,200
8,200
24,200
7,100
6,800
4,200
4,500
8.7
16,000
5 x 104
6
b
Form.
40
1.5
72
4,900
4,000
10,000
3,200
3,300
1,900
2,200
8.1
7,700
6 x 106
7

Quat.
38
1.7
72
10,600
8,200
21,500
5,700
8,400
3,900
4,800
9.2
20,500
2 x 105
Zinc  sulfate.
Formaldehyde.
Quaternary ammonium compound.
                                   28

-------
Their comparison shows a moderate decrease in COD and BOD5 with a
slight increase in SOC after 72 hours.  These results are evidence of
normal decomposition and stabilization by microbial activity.  Samples
3 through 7 were all prepared from the control  (Sample 1).  Specific
chemical additive was added to undiluted control sewage and aged for
72 hours. These results are given under Samples 3, 5, and 7.  Similarly,
control sewage was diluted 100 percent with tap water (halving the
constituent concentrations), mixed with specific chemical additives,
and aged for 72 hours.  These results are given under Samples 4 and 6.

Comparison of the aged control sewage  (Sample 2) to the same sewage
treated and aged with specific chemical additives  (Samples 3, 5, and 7)
provides a basis for evaluating the effects of specific additives on
the waste characteristics.  The zinc sulfate additive in Sample 3
caused a significant increase in SS while formaldehyde had no similar
effect on Sample 5.  Both additives caused a major increase in COD and
a slight increase in BODs.  SOC was actually decreased in Sample 3,
possibly by the insolubilization of zinc organic salts.  Formaldehyde
indicated no effect on SOC.  Quaternary ammonium additive appeared to
cause a slight increase in COD and TOG but a decrease in BOD5 and SOC.
Formaldehyde additive had the greatest effect in reducing the coliform
population.

The interpretation of these results must be qualified.  Under the dy-
namic conditions of aging concentrated sewages, it is impossible to
determine the true net effect of the chemical additives.  Comparison
between these sewage samples provides at best only qualitative data.
Samples 4 and 6 may only be compared to each other as an indication
of specific additive effects on more dilute wastewater.

Table 8 gives the treatability data as a function of sewage suspended
solids and chemical additive concentration.  Percent relative res-
piration rate values for zinc and quaternary ammonium-treated sewages
are less than those for the control.  Formaldehyde treated sewages
have rates greater than the control.  These results are shown graph-
ically in Figure 5 as a plot of percent relative respiration rate
versus sewage suspended solids.   Separate plots are given for the
control and each chemically treated sewage.  The limiting condition
of zero suspended solids concentration represents infinitely dilute
sewage.   Data points at this limit are the percent relative respiration
rate values for activated sludge mixed liquor having a recommended
dosage of specific chemical additive.

These results were used to evaluate qualitatively the treatability of
simulated holding tank wastewaters.  As defined, percent relative res-
piration rate values greater than 100 indicate greater microbial res-
piration activity compared to the endogenous state.  This is the re-
                                  29

-------
co

 0)
0)
4J
(S O
0
01 rH
-P >

01 4-1
U Cd r4
r4 rH X
0) CD X,
p^ pr; ^
G
•H
> -e
4-1 » rH
cd CD \
rH 4-i tn
o) cd £
Cd Pd —
"G
0) -H
U r4g
C X \
CD \.
rH •• rH
CD CD \
IH 4-1 tn
0) cd 5
(O
° 1
4-J t
o -—
fe Q
o
Tj CD
cd _
3 f
rH
CD \
to tn
> .g

s \
c/> \
w tn
t— 1 £

CD ,—
Cn rH
03 \
s en
CD g
CO —


0)
rH CD
it >
U -H
•H 4-1
CD T3
.C T3
U <









Oj
CN
*




CO
CN
rH





CN
O
ro
O





Ol
ro
ro
0

0
cn
00
rH
O
in
CN
CN
O
CO
cn
~
en



3
cd
V-l
CD
« en
c s
O 01
Z tn









v£> r^ o oo
o co co co
rH ro in r-



O rH O O
o o k£i r^
^j1 cxj r- kD
O O rH rH





en r~ CN IN
r> o o rH
ro CN ro CN
o o o o





CTl rH O
1 ro  ^ in CN
ro rH CN ro
rH CN CN CM
O O O O
kO CN -31
t^ on CN
^ ..
•^t o
rH
CD"
TJ

r;
0)
T) O
(H ^T
cd
g^
0 0
D4 U







kD CO
. .
en <^ o o cn
1^3 ,_t CT, ,-(
.H ^ m



i-H CNJ ro O
^ ro ro ^ 'kD
O «H ro O ^
O O O rH O





o r-* CN CN r--
ro O O r—* O
M1 CN CO  LO o
I CN rH o r-
1 O 
-------
J
o
                                                en
                                                a
                                                H
                                                O
                                                w
                                                a
                                                w
                                                O
                                                I
                                                w
                                       o
                                                          0)
                                                          tr>
                                                          rfl
                                                          T)
                                                          G
                                                          •H
                                                          -P
                                                          •H
                                                          u
                                                          •rH
                                                          g
                                                          Q)
          §
         •H
         -P
          U

          P
         4-1
                                                          tn
                                                          (0
         •H
         r-t
         •H
         XI
          Iti
         4-)
          nj
          0)
          !H
         -P
                                                          S 0
                                                          Q) cn
                                                          w
                                                             T)
                                                          0) (!)
                                                          > T3
                                                          •H C
                                                          -P a)
                                                          03 ft
                                                          i-H W
                                                          QJ 3
                                                          OH W
                                                          LD

                                                          0)
                                                          cn
                                                         •H
aAiiva3H
  31

-------
suit of the presence of biodegradable nutrients available for as-
similation by microorganisms.  Conversely, values less than 100 in-
dicate a condition of microbial activity that is less than its normal
endogenous respiration rate.  This results from the inactivation or
death of microorganisms caused by the presence of toxic substances.
The application of relative respiration rate as an indication of
sewage treatability is based on this logic.

Results indicated that treatability of sewage was a function of speci-
fic chemical additive and sewage strength.  At low suspended solids,
zinc-treated and quaternary ammonium-treated sewages were toxic to
activated sludge.  With increased solids concentration, these sewages
were less toxic.  Sewages containing formaldehyde were biodegradable
over a broad range of suspended solids concentration with no adverse
effects on activated sludge.  Significant evidence was given to in-
dicate that the treatability of sewages containing formaldehyde;
additives was much greater than those containing zinc or quaternary
ammonium chemical additives.

Additional respirometer studies were conducted to evaluate the relative
treatability of domestic sewage mixtures containing increased amounts
of chemically treated wastes.  Combining domestic sewage with industrial
wastewaters before treatment is common practice.  The effect
of increased chemical additive concentration on activated sludge was
determined under simulated mixed sewage conditions.

Identical waste samples were charged with 4.5 mg/1 of zinc and formalde-
hyde additives  (Codes 26 and 40) and aged at 25°C for 72 hours.  Por-
tions of these wastes were combined with fresh settled domestic sewage
to give domestic/chemical sewage mixtures of 50/50 and 75/25 percent,
respectively, by volume.  These mixtures, having approximately 3300
mg/1 SS, were added at a constant loading factor of 1.6 to 1.8 to
activated sludge mixed liquor which had been previously characterized
for the reference respiration rate.  Each activated sludge/sewage
mixture was then aerated and analyzed for its relative respiration
rate.  This same procedure was applied to the domestic sewage having
114 mg/1 SS and the original full-strength chemical waste samples.
Table 9 gives the respiration rate data for this study.

Sewages containing formaldehyde-treated wastes had greater respiration
rates than those containing the zinc additive.  Relative respiration
rate data indicated that the treatability of sewage mixtures contain-
ing zinc was less than the untreated domestic sewage, indicating
toxicity to activated sludge.  As the volume percent of zinc-treated
wastes increased, the toxic effect also increased.  These results
are shown in Figure 6.  Since percent of chemical waste composition


                                  32

-------
§
H
E-i
H
CO
u
w
pa
CO
§
H
D
CH
co
I
Q
1-3
H
ffl
4->
(d
« 0
0
 H
Jj ^
C -H X

CL, O
3§
o «;
J 01
e
to
0) -~
tjl rH

S &>
 0
i &
0) O
0) U



U -H
•H +J
% -0
u D O
i/> r~ en




o t

I
o o





ID 1/1
O O 1
CN CN 1
• 1
O O

O O
rH rH

rH rH 1
O O 1
CO CO
rsl cv)
CN) CM




,C
CO rH l£>
00 CO rH
H rH IN

O O 0




rH O O
CN O O
f) t*) n
rn co m
O rH O rH Id -H
•H nj -H id u -P
4-1 U 4-1 U -H M
W -H {/} -H g CD

§ .C 0 XI O S
Q U Q U
tX> 
dC tfP tfP * O O
irt in o o o
r^ CN 1/1 in rH
 <^
r*- 'lO i
m m i
i
o o





m m
o o i

rH rH 1
O O 1
CO CO
fN fN
CN CN





O CN -°
rH rH rH

d o o




o o o
«^ m o
 O ro
(N m ro
* * rH U
O rH U rH (TJ -H
• H fU -H fCj U 4-1
4J O 4-> O -H W
tlQ -H (/I -H SO)
OJ g 0) E OJ S
E S E Q) X 0
Sx o x; u D
U Q U
dP dP dP dP O O
m m o o o
r-~ (N m m ,H
0)
4J
(0
H
W (N
1
O (U
•H 0
N 0
T)
O
•O

01
a
en
o
o
                                                                                        T3
                                                                                         D
                                                                                         fl
                                                                                         U
                                                                                              5

                                                                                              S
                                                      33

-------
                                                      co  w
                                                      Q  U

                                                      dP  dP
                                                      O  O
                                                         O
                                                      W  10
                                                      Q  U

                                                      dP  dP
                                                      ID  ID
                                                      CN  r^
                                                      co  to
                                                      Q  O

                                                      dP  dP
                                                      m  m
                                                      r-  fN
                                                      to  co
                                                      D  O
                                                      dP  dP
                                                      O  O
         CJ  CO
         H  U
         co
         M  H

         d  <
         Q  S

         |H  t/5

         M  i-l

         PS  U
         M  H
         PJ  S

            X
          -o
to  w    Z
Q  U    OH

dP  dP    E-i  W
O  O    HO
m  in    wo!
         o  w
                                                              O Q
                                                              U Z
                                                              U)
                                                              3:  Q
                                                              U ^
                                                              c/1
         H  W
                     §
                     •H
                     -P
                     •H
                     W



                     I
                     O

                     ID
                     -P
                     M
                     id
                     u
                    •H
                     a
                     0)
                                                                           c
                                                                           0)
                                                                           u
                                                                           M
                                                                           Q)
                                                                           a
                                                                          C
                                                                          0
                                                                          •H

                                                                          U
                                                                          C

                                                                          M-l

                                                                          fd

                                                                          en
                                                                          (d
                    4-1
                    •rH
                                                                          4J
                                                                          (0
                                                                          0)
                                                                          0)
                                                                          en

                                                                          Q)

                                                                         •H
                                                                          a
aAIlv^aa
             34

-------
can be equated to chemical additive concentration, substantial
evidence is given that increased zinc concentrations resulted in
decreased sewage treatability.  Sewages containing formaldehyde had
relative respiration rate values greater than the untreated domestic
sewage and, as formaldehyde concentration increased, the relative
treatability of these sewages increased and then reached a plateau.
DISCUSSION

A relative indication of the maximum tolerable zinc concentration in
sewage that  will not have an adverse effect on the activated sludge
process was given in the respiration rate data.  Toxic effects from
increased zinc concentration were indicated by percent relative
respiration rage values less than those for the domestic sewage control.
A sewage composition of 3 percent zinc treated waste  (97 percent
domestic sewage) gave the first measurable effect of  toxicity.  This is
shown in Figure 6 as the point of separation between  the plots for the
domestic sewage control and zinc treated sewage mixtures.  The cal-
culated zinc concentration of this sewage mixture was 40 mg/1.  These
results indicated that sewage mixtures containing more than 40 mg/1
zinc have adverse effects on the activated sludge process.  This zinc
content will occur in sewage mixtures that contain approximately 3 per-
cent (by volume) of undiluted waste charged with the  recommended
dosage of zinc-type chemical additives.  Undiluted waste refers to
the original sewage from recirculating/retention systems.  It is com-
mon practice to flush these systems after emptying.   Typical rinsing
dilutes the waste pumpage volume by 50 percent.  In this case, the
maximum tolerable amount of zinc-treated wastes would be approximately
5 percent by volume.

Formaldehyde-treated wastes gave no sign of toxicity  to activated
sludge.   Previous respirometer studies showed that formaldehyde
additives are biodegradable at low concentrations and cause an in-
crease in the relative respiration rate of activated  sludge.  High con-
centrations of formaldehyde in sewage would be expected to have toxic
effects on activated sludge.  This result is not shown here.  Formal-
dehyde is very reactive and will combine readily with proteins and
ammonia-*- .  The extent of tormaldehyde reaction with  sewage in-
gredients will determine the free formaldehyde-concentrations and
its effect on microorganisms.  Low formaldehyde concentrations will
be biodegradable as nutrients,- large concentrations will be toxic.
Therefore, the effect of formaldehyde on sewage treatability is a
function of sewage characteristics as well as formaldehyde concen-
trations.
                                35

-------
Sewage characteristics have similar effects on the toxicity of zinc and
quaternary ammonium compounds.  Chemical reactions may remove these
constituents from solution and reduce their net toxic effect.  Zinc
ion will readily complex with proteinaceous colloids as well as combine
with microbial floc^.  Quaternary ammonium salts completely dis-
sociate in water, and quaternary ammonium ions are very reactive with
bases and alcohols common in proteins and carbohydrates.  The ability
of microorganisms to assimilate specific reaction products will affect
the treatability of the sewage, and the extent of reaction will de-
termine the remaining concentration of chemical additive ingredients
and their effect on the activated sludge.  Therefore, treatability of
sewage is a function of both chemical additive concentration and sew-
age characteristics.
                                   36

-------
                              SECTION VII

             ACTIVATED SLUDGE TREATMENT OF CHEMICAL WASTES
Respirometer studies produced the significant result that biological
treatment of sewage was adversely affected by the presence of specific
chemical additives at relatively low concentrations.  Since the corre-
lation between aerobic respiration rate and treatability was strictly
qualitative, a detailed activated sludge treatment study was conducted
to substantiate the respirometer results.

Domestic sewage from a common source was mixed with varying amounts of
specific chemical wastes and fed to three replicate, activated sludge
plants.  One plant was operated on domestic sewage alone as a control.
The loading factor was held constant for all three plants.  Differ-
ences in effluent quality, organic removal efficiencies, and cell yield
values between the control and test units were attributed to the pre-
sence of the specific chemical additives.

The objective of this study was to determine the level of specific che-
mical waste that can be tolerated in wastewaters without reducing the
efficiency of the activated sludge treatment process.  The efficiency
of the process to remove specific chemical additives was also to be
evaluated.
PLANT OPERATION

The activated sludge treatment process was simulated in a 210-liter
(55-gallon) drum reactor equipped with a sintered ceramic air diffuser.
Three replicate reactors were used:  one as a control and two as test
plants.  A "fill and draw" technique was employed twice daily with
aeration periods of 6 and 12 hours to simulate diurnal flow patterns in
plug flow plants.  Mixed liquor volatile suspended solids were main-
tained constant by proper wasting.  Feed, effluent, and mixed liquor
samples were taken twice daily for analysis.  Each feed cycle continued
for five days.
                                    37

-------
PREPARATION OF FEED CHEMICAL SEWAGE

Fresh sanitary wastes from portable toilets at local construction sites
were blended in a 950-liter tank.  The measured suspended solids con-
centration was 17,500 mg/1.  Portions of this waste were diluted with
water until each had a suspended solids concentration of 2100 mg/1, rep-
resentative of typical watercraft waste pumpage.

Based on the manufacturer's recommended dosage, 841 grams of formalde-
hyde additive (Code 40) was added to 190 liters of prepared waste.  The
calculated formaldehyde concentration of this waste sample was 1575
mg/1.  Similarly, 835 grams of zinc additive (Code 26)  was mixed with
190 liters of identical waste.  The calculated zinc concentration of
this mixture was 1400 mg/1.  Both chemically treated waste samples were
aged at 25 C for 3.5 days, separated into 11- and 19-liter portions,
and refrigerated at 2 C.

Portions of each chemically treated sewage sample were analyzed imme-
diately after their preparation and then analyzed again after 3.5 days
aging.  Similarly, the control sewage without chemicals was analyzed
after equal aging.  Comparisons between chemically treated and untreated
aged sewage samples showed significant differences because of the pre-
sence of the specific additive.  Zinc treated wastes showed a signifi-
cant increase in SS with a loss in TOC, possibly caused by the zinc com-
plexing with colloidal solids.   Similar aged wastes containing formalde-
hyde had nearly doubled concentrations of COD, BOD, and SOC.  Both
coliform and total bacteria contents of the chemically treated sewages
were greatly reduced.  The measured formaldehyde concentration of the
aged waste was reduced because of chemical reaction and evaporation
losses.  Unfortunately, no data were obtained describing the original
control sewage to allow more accurate comparisons between unaged
(zero time) chemically treated and untreated sewage samples.
PROCEDURES

Each drum reactor was charged with 75 liters (20 gallons) of activated
sludge taken from a package treatment plant processing 190 kl/day
(50,000 gal/day) of domestic sewage from Santa Clara, California.  Fresh
settled domestic sewage from the same source was added and the mixture
aerated for 6 hours.  Supernatant effluent was removed after 2 hours of
settling, and domestic sewage was again fed to each reactor followed by
12 hours of aeration.  This procedure was repeated for 5 consecutive
days with proper wasting of mixed liquor to give a healthy, stabilized
activated sludge in each reactor with a 1200 mg/1 average mixed liquor
volatile suspended solids concentration (MLVSS).


                                    38

-------
Table 10.   COMPARISON  OF CHEMICALLY  TREATED FEED  SEWAGES FOR ACTIVATED
            SLUDGE PILOT PLANT STUDIES
Parameter
Active Chemical:
Age (days) :
SS (mg/1)
VSS (mg/1)
TS (%)
TVS (%)
TOC (mg/1)
SOC (mg/1)
BOD5 (mg/1)
COD (mg/1)
T-N (mg/1)
NH3-N (mg/1)
pH
T-PO (mg/1)
Conductivity (MHO)
Zinc (mg/1)
Formaldehyde (mg/1)
Coliform (MPN/100 ml)
b
Total Bacteria (SPC)
ontrol
None
3.5
2,080
1,673
0.37
0.23
1,240
550
1,140
2,740
820
196
8.9
210
4,000
0.5
<0.2
23 x 107
6
14 x 10
Sample A
Formaldehyde
0
2,420
2,010
0.49
0.32>
1,830
1,225
2,560
5,400
600
410
7.4
218
6,600
	
1,575C
	


3.5
2,260
1,950
0.51
0.34
1,920
1,260
2,500
5,320
625
210
7.1
213
4,700
	
<1,100
23 x 101

50
Sample B
Zinc
0
3,460
2,370
0.83
0.47
1,330
560
1,450
2,880
425
175
6.9
270
3,100
1,400°
	
	


3.5
3,760
2,300
0.86
0.49
1,035
530
1,630
2,090
590
190
7.2
240
4,000
1,300
	
^45

170
     Chemical Code 40
     Chemical Code 26
    'Calculated values based on chemical  additive composition
     Standard Plate Count'   the number  of  organisms per milliliter of sample
                                        39

-------
Three series of mixed sewages containing 1, 5, and 12 percent (by
volume) of chemical waste were treated by the activated sludge process
for 5 consecutive days.  A two-cycle per day "fill and draw" technique
was followed with aeration periods of 6 and 12 hours.  Feed sewage
samples were prepared twice daily, using fresh, settled, domestic sew-
age and chemical sewage.  Refrigerated feed chemical waste samples were
warmed to ambient temperature and diluted 50 percent by volume with
fresh water.  This dilution accounted for the flush water commonly used
to clean the holding tank or toilet system after the initial pumpout.
Specified volumes of diluted chemical wastes and fresh domestic sewage
were mixed and fed to respective reactors.  The volume of each mixed
sewage feed sample was controlled to maintain a constant loading factor
of 0.25 in each reactor.

Samples of feed waste and supernatant effluent were collected from each
reactor twice daily, composited, and analyzed for 11 chemical and bio-
logical parameters.  Samples of mixed liquor were taken after the 12-
hour aeration period and analyzed for SS, VSS, temperature, pH,  conduc-
tivity, and DO content.  Mixed liquor was periodically removed from
each reactor to maintain constant MLVSS.  A sludge volume index (SVI)
was determined for each mixed liquor as a measure of its settleability.
Mixed liquor samples were examined microscopically for changes in mi-
croorganism population, sludge size, and configuration.  Photomicro-
graphs were taken to show the physical results of any toxic effects
from increasing zinc and formaldehyde concentration.
RESULTS

Differences in effluent quality and degree of treatment between the con-
trol and test reactors gave evidence of the relative effects of specific
amounts of zinc- and formaldehyde-treated wastes.  Table 11 gives the
average removal  efficiencies  for activated sludge treatment of various
domestic/chemical sewage mixtures.  Characteristics of these feed sew-
ages and corresponding effluents are also given.

Activated sludge treatment of feed sewage mixtures (1 percent by volume
zinc-treated wastes, 99 percent by volume domestic sewage) having 9
mg/1 zinc gave effluents that had slightly higher concentrations of
TOC, SOC, COD, SS and turbidity compared to those of the control.  No
relative difference in BOD5 removal was noted.  However, some indica-
tion of loss of reliability of BOD5 data due to toxic effects of zinc
is given in the lower removal efficiencies of TOC, SOC, and COD.  Other
feed sewage mixtures (1 percent by volume formaldehyde-treated waste,
99 percent domestic sewage) having 10 mg/1 formaldehyde gave effluents
that showed no significant difference in quality compared to the control.


                                      40

-------
o
&
H
&
H

£
z
o
u

co
w
o
<:
co

s
EH
z
w
«;

§
EH

W

Q   CO
D   W
rj   EH
CO   CO
H
EH
U
     EH


     >H
EH   O
J   H
D   S
CO   W

§   O







Q

0
0











CJ

O
en














u
O

H





CU 4J
§e
01
rH O
0 H
> 0!













01 4J rH
en c u)
id Q) >


< en a
0) 4J
00 C —
rt CU rH
H 3 v.
01 -< tji
> 14-1 g

u
0)
00 —
rt T3 *H
h 0) ^N
CU 0) ff>
> fa ,§
0) 4J rH
Cn C ni
nj 0) >
rl 0 0


«! ft «
0) 4J
00 B ~*
CO 0) -H
U 3 \
01 r-l O>
> 14H B
< 14H ~-
Ed
0>
00 ^
W T3 rH
H 01 \
0) 0) rp
> fa E
< -5
O 4-1 rH
Cn C id
rd o t>
V4 U 0
> (U 01
< Oi &

0) 4J
oo c ^
crt qi .
)-< 3 \

> UH S1
<* C4-I -O
Ed
01
00 —
r4 0) \
> fa _e
*]i

u
CD .—
CJ CJ rH
"g 0~cn
^ &
o

"~i T3
CJ S 00
'*H d. cfl
1 c|



O> CTN OO CJ\ C30 00 CJ\ f^ Fv







CN i-l




InSS SScQ §S§

^H
oo oo oo ON r^. oo ON oo r*^





rH VO rH fO CM





3SS SSoo SOON
CM CM



ON ON 00 ON f* 00 CJ\ 00 OO





i— ( CM -^ 00 i— 1 O ON ^O rO
r- 1 i— ) rH ON CM CO CO






ooO1^ cocMr-N- i— i oo en
i— 1 CM CM CMOO-3" rH<|-vD
^
rH rH rH
O O O CO <-t
H O 0 M -^ tt - •
JJ * • 4J vO 4JCOCM
^ rH i— ( CfOUl fJrHrH
O O ^-^ O
U 0 0

•*. ^ "co



0) O) 01
'O T) T3
>!>*>>
CU 0) 01
T3 -0 T)
l-H r-t l-H
e C C c B c e E c
O O -H O O -H O O >H
atuN KfacsJ fSCuNl







Q

O
CO










H
M
Q
1— 1
m
g
H










C4
J




S
s
§



















ON ON ON ON ON ON ON ON ON





ooor^. r^-rHcM cooo
rH f*-. rH rH r-t
^




-j-vovo omcs OVOCM
OOOO rHOI^ CMCOrH
CMCMrH CMCOCM CMCOCO
i— 1
vO vD »^ TH vo Px O O O




co co *n in r^ rH vo oo c^
CM rH CM





vO 00 "J" ON ?H CM «J" «d" O
rH rH



CTN ON ON ON 00 00 ON ON OO
^**




^^^ ^SS °irQI3
p- "O O ^O — CO
rH




vo CM CM H


0) »>!>•>
>rH
                                                                                                                      J5  O
                                                                                                                       0)  r4
                                                                                                                      •a  u
                                                                                                                      -t  c
                                                                                                                       ctj  O
                                                                                                                       E  u
                                                                                                                      ol
                                                                                                                      00 rH
                                                                                                                      m  o

                                                                                                                      60 -H
                                                                                                                       u)  oo
                                                                                                                      J-  crj

                                                                                                                       cu  01
                                                                                                                       00  CO
                                                                                                                       CO
                                                                                                                       3 -a
                                                                                                                       o)  o>
                                                                                                                       CD  eu
                                                                                                                         MH
                                                                                                                      "O
                                                                                                                       01  }H
                                                                                                                      1
                                                                                                                      T)  O
                                                                                                                      0) 4-1
                                                                                                                      0)
                                                                                                                      U-i  0)
                                                                                                                          to
                                                                       41

-------
A significant drop in effluent quality and decreased removal efficiency
occurred with treatment of feed sewage mixtures having 47 mg/1 zinc.
This feed sewage consisted of 5 percent by volume zinc-treated wastes
and 95 percent by volume domestic sewage.  A similar decrease in efflu-
ent quality occurred with the treatment of feed sewages having 140
mg/1 formaldehyde.  This feed sewage consisted of 13 percent by volume
formaldehyde-treated wastes and 87 percent domestic sewage.

The results of slug feeding mixed sewage having 36 percent chemical
waste and a formaldehyde concentration of 380 mg/1 are given in paren-
theses in Table 11.  After 6 hours of slug feeding, uncontaminated do-
mestic sewage was fed to the reactor for the following 4.5 days.  A
major upset of the biological process occurred as evidenced by a signi-
ficant drop in effluent quality.  Increase in TOC and BOD5 may have re-
sulted from the chemical addition, but SS data does indicate a drop in
treatment performance.  Normal process efficiency and effluent quality
were restored 72 hours after initial shock loading.  Figure 7 shows the
effluent characteristics for 5 consecutive days following slug feeding.

Microscopic examinations were made of mixed liquor samples throughout
each treatment series and photomicrographs were taken periodically to
compare sludge characteristics.  Mixed liquor contaminated with 9 mg/1
zinc for 5 days showed no significant difference as compared to the
uncontamined control.  The full range of microorganisms characteristic
of active healthy sludge was present.  Sludge colonies were spherical,
normal size, and contained equal amounts of bacteria filaments.  At 47
mg/1 zinc, a significant reduction was noted in the number and type of
microorganisms.  Populations of ciliated and flagellated organisms were
most reduced.  Sludge colonies became fragmented and bacteria filaments
were significantly reduced.  At 113 mg/1 zinc, very little biological
life was detected.  Rotifers, flagellated protozoa, and free-swimming
ciliated protozoa were killed, while stalked ciliated protozoa were in-
activated.  Sludge size was greatly reduced and fractured and no bac-
teria filaments were present.  These changes in sludge characteristics
as a function of zinc concentration are pictured in Figure 8.

Mixed liquor samples containing varying amounts of formaldehyde were
similarly examined and photographed.  At 10 mg/1 formaldehyde, no signi-
ficant difference was detected when compared to the mixed liquor from
the uncontaminated control reactor.  Mixed liquor samples contaminated
with 140 mg/1 formaldehyde for 5 days showed a slightly smaller microor-
ganism population than the control.  Flagellated and ciliated protozoa
and rotifers were present in reduced numbers.  Sludge colonies became
quite clustered and bacteria filaments were greatly reduced.  The
changes in sludge characteristics as a function of formaldehyde concen-
tration are pictured in Figure 9.

                                      42

-------
100.
 90 _
                                                LEGEND
                     TIME AFTER SLUG-FEED, HOURS
  Figure 7.  Effluent characteristics after slug-feed of 380 mg/1
             formaldehyde
                                    43

-------
A.  Control - No Zinc (35X)
C.  9 mg/1 Zinc, 5 days (35X)
E.  47 mg/1 Zinc, 5 days (35X)



                ^r
     ,*E^
 '**"&$^'

 J^^L&r
 •.. % -3?*^>^

*>/*** '^Pii
                       B. Control - No Zinc (100X)



                           -p
                       D. 9 mg/1 Zinc, 5 days (100X)
                                       	

                       F.  47 mg/1 Zinc, 5 days (100X)
G.  113 mg/1 Zinc, 5 days (35X)    H. 113 mg/1 Zinc, 5 days (100X)
Figure 8.  Photomicrographs of activated sludge exposed to increased

       zinc concentrations
                    44

-------
                                                         -*.>v*


                                                                    g
A.  Control.  No Formaldehyde  (35X)  B.   Control.   No Formaldehyde (100X)
C.  10 mg/1 Form., 5 days  (35X)
D.  10 mg/1 Form., 5 days  (100X)

        Tf
i	  .*••>_		mi i"     i	__ •**
E.  380 mg/1 Form.,  Slug-Feed (35X)  F.  380 mg/1 Form., Slug-Feed  (100X)
G.  140 mg/1 Form., 5 days  (35X)     H.   140 mg/1 Form., 5 days (100X)
Figure 9.  Photomicrographs of activated  sludge  exposed  to  increased
           formaldehyde concentrations
                                 45

-------
Slug feeding of mixed sewage containing 378 mg/1 formaldehyde caused
relatively little change in the activated sludge characteristics.
After an initial reduction in rotifers and flagellated protozoa, normal
populations of microorganisms were attained within 48 hours after shock
loading.

Material balances were determined for each treatment series in order to
best describe the dynamic operation of the activated sludge process when
treating different sewage mixtures.  The average daily increase of
MLVSS was determined as a measure of the plant's production of biomass.
The average daily removal of total organic carbon (TOC)  was determined
as a measure of food consumption.  BOD removal data normally used for
this measure were not applied, because of questionable results relating
to the toxic effects of the chemical additives.  The ratio of these
values, AMLVSS/ATOC, provides a useful measure of biological activity
that can be compared to different plants or within the same plant treat-
ing different sewages.  For purposes of this research, loading factors
and MLVSS concentrations were kept relatively constant in the control
and two test plants.  This condition allowed the comparison of biologi-
cal activity between plants, with any differences indicating the effects
of zinc and formaldehyde in feed sewages.  These results are given in
Table 12.

A more accurate measure of the biological activity of each activated
sludge plant was determined by calculating a cell yield coefficient,
Ky, as defined by the following expressions:

           AMLVSS = Ky (ATOC) -  (MLVSS)  (C) (k )        (1)
               KY = iT^r^l + \tf^^\  (O  dO         (2)
     Where Ky     = cell yield coefficient

           AMLVSS = average change in MLVSS per unit time, day

           ATOC   = average removal in TOC per unit time, day

           MLVSS  = average mass of MLVSS, gm

           C      = biodegradability factor

           k      = endogenous respiration rate, day
                                       46

-------
Cn
O
W
EH

W

Q
D




Q
CJ
w  cn
O  W
    W
H
H  P
U  W

    <
J  J
W  I-H
M  
0 O O
!-" H G
Q) O
p I p*j

*
CO
CO CJ
|B
CJ CO i-H|
O CO — J E
H > M a
CJ 'Hi
H O1 "*
< ~
W X. >i
1 ?y
o
0)
60 CO
<« CO ^
*•< > E

O O "-H
•H (3 \

r! —
O


^H (1)
rt >
O -H
•«H i '
§.,_!
*Q
J3 13
0 ~H CO CO
CM CM CM



r^ CM i^«
0 .-H 0
CM CM CM
1
I o cn
! i-H


O (1J
VJ 13
4-) h)-.
c j:
O (U
O T3
S^ ^/ I— 1
fd
QJ E 0
a S c
0 0 -M
2: fl, Cs]

CO ^O
ON CO


m ^t
0 CD*

<}• VO
O ON
.-H O
CM CM
i-H i-H
 CM
CM CM CM
1 O ro
1 H H


O <1>

4J >>
C ^
O 
-------
The endogenous respiration rate of each plant's mixed liquor was deter-
mined during 50 days of continued aeration without feed.  The volcitile
suspended solids concentration was determined each day and plotted as a
function of time.  Applying standard equations given in the literei-
ture  '   ,  the endogenous respiration rates and biodegradability fac-
tors were calculated.*  All three mixed liquors had equal endogenous
rates of 0.064 day"1 and biodegradability factors of 0.55, 0.51, and
0.52 for the control, formaldehyde-treated, and zinc-treated sludges,
respectively.  These data were applied to equation (2) with the result-
ing cell yield coefficients for each treatment series presented in
Table 12.

The disposition of zinc in the activated sludge process was followed by
analysis of feed and effluent samples.  These results are given in
Table 13.  Total zinc concentration was determined by atomic absorption
analysis of the sample ash redissolved in acid.  The range of values
was quite large.  The original amount of zinc added was calculated from
feed sewage volume data and the known zinc concentration  (1400 mg/1) of
undiluted chemical waste.  No sludge samples were analyzed for zinc
content, but previous work  reports zinc removal by microbial floccula-
tion with zinc accumulation in the sludge.

        Table 13.  ZINC DISPOSITION IN ACTIVATED SLUDGE PROCESS
Zinc
Added
(mg/1)
0
9
47
113
Average Total Zinc Concentration, (mg/1)
Feed Sewage
1.2
5.8
41.0
120.0
Effluent
0.7
2.2
5.3
12.0
*In unpublished works, Hobbs has derived equations defining the biode-
 gradability factor, C.  This derivation is given in Appendix D.
                                       48

-------
DISCUSSION

Comparison of AMLVSS/ATOC and Ky values indicated a decrease in biomass
production and microbial activity as the volume percent of chemically
treated wastes was increased in the feed sewage.  Feed sewages contain-
ing 1 percent (by volume) of chemical waste and 10 mg/1 zinc or formal-
dehyde had little or no effect on activated sludge.  However, a signi-
ficant reduction in biological activity resulted with feed sewages
containing 47 mg/1 zinc  (5 percent by volume zinc-treated wastes)  and
140 mg/1 formaldehyde (13 percent by volume formaldehyde-treated
wastes).  Lower removal efficiencies and effluent quality data sub-
stantiated these results.

A maximum nontoxic zinc concentration of 15 to 20 mg/1 was determined
from a plot of normalized Ky values versus zinc concentration.  This
range agrees very well with zinc toxicity data reported in the litera-
ture  '  '  9.  These results indicated that sewages having more than
2.5 percent (by volume)  of zinc-treated wastes would have adverse ef-
fects on the activated sludge process.  The zinc concentration of these
sewages would be greater than 20 mg/1 based on zinc additive dosage and
50 percent dilution of the original waste with flush water.

Effluent qualities, removal efficiency data, and cell yield values in-
dicated that the maximum nontoxic concentration of formaldehyde was 100
to 120 mg/1.  Gellman and Henkelekian^-^ reported a higher toxic range
of 135 to 175 mg/1 formaldehyde from laboratory respirometer studies.
Gilcreas   reported that 100 mg/1 formaldehyde completely halted the
operation of a sludge digester and that similar formaldehyde concen-
trations in wastes from a penicillin plant caused major upset of a
municipal treatment system.  It was concluded that sewage containing
more than 120 mg/1 formaldehyde would have an adverse effect on the
activated sludge process.

Since specific formaldehyde additives had such varied effects on acti-
vated sludge respiration rate, it is difficult to predict the maximum
tolerable percentage of formaldehyde-treated wastes in general.  For
the specific formaldehyde additive (Code 40) used in the completely
mixed studies of this work, it can be stated that sewages having more
than 12 percent (by volume) formaldehyde-treated wastes will cause up-
set and loss of removal efficiency to the activated sludge process.
The formaldehyde concentration of these sewages would be greater than
120 mg/1, based on recommended dosages of chemical additive Code 40 and
50 percent dilution of original wastes with flushwater.


                                      49

-------
                             SECTION VIII

                        PROCESS DESCRIPTION


The FMC Waste Treatment System employs a physical/chemical process to
treat sanitary sewage and other wastes.  Chemicals are added to con-
dition the sewage, which is then filtered to remove suspended solids.
The system operates automatically on demand, with instantaneous on-
off treatment capability.  Influent sewage flow may be constant or
variable, with no loss in degree of treatment.

During the process, chemicals are added automatically in proportion to
the influent sewage flow rate.  The type and function of each chemical
is as follows:

     1.  Bactericidal Agent.   A bactericidal agent, chlorine, is used
         to destroy bacteria and inactivate viruses present in sewage so
         that the effluent water and solid filter cake are free of live
         pathogenic organisms.

     2.  Activated Carbon.  Powdered activated carbon is used to adsorb
         certain soluble organic compounds in sewage that could not be
         removed by filtration.  Once adsorbed, they are readily re-
         moved by filtering out the spent carbon particles.

     3.  Flocculating Agent.   A flocculating agent, aluminum sulfate,
         is used to destabilize the colloidal particles of sewage.  The
         result is the coagulation of many small colloidal particles
         into large floes, which are removed by filtration.

     4.  Filter Aid.  A filter aid, diatomaceous earth, is used to
         assist the filtration process.  Diatomaceous earth is a finely
         divided, insoluble,  rigid material that will not compact or
         channel when forming a mat during filtration.  This maintains
         the filtration rate by preventing fine gelatinous solids from
         blinding the filter surface.

The basic process, shown schematically in Figure 10, involves four
operations: (1)  comminution,   (2)  disinfection, (3) flocculation, and
(4) vacuum filtration.
                                     50

-------
                             ooHOPrERooo
                              ooooooooo
                              IOOOOOOOO
                              oooooooo
                              ooooooo
                              ooooooo
                               00000
                               JOOOO
                               oooo
     Figure 10.  Schematic drawing  of  FMC waste treatment system
Influent wastes are coarsely  screened and comminuted to reduce solid
particle size. A bactericidal agent  (aqueous chlorine)  is added auto-
matically with a metering pump.   This treated mixture flows to an
agitated surge tank designed  to  handle anticipated load fluctuations.
A dry chemical mixture of activated  carbon and filter aid is added
automatically to the surge  tank  by a vibrating feed mechanism supplied
from a hopper above the tank.  At a  set level, sewage in the surge
tank is moved by a low-volume pump into a reactor coil wound around
the surge tank.  Before entering the coil,  chemical flocculant is
added automatically to the  sewage/chemical mixture by a metering pump.
The coagulated sewage mixture then flows to a rotary vacuum filter,
which separates solids from the  liquid.   Sewage solids, filter aid,
and carbon retained on the  drum  filter fabric are removed with a "wire
doctor blade."  The clear effluent passes through an air separator
tank before being discharged.  The solid filter cake is accumulated
and disposed as sanitary landfill.
                                      51

-------
                                          IZ9ZS
                                                       0)

                                                      -p

                                                      14-1
                                                       0

                                                       w
                                                      4-1
                                                       c  o
                                                       a;  o
                                                       c  o
                                                       g  o
                                                       O  tn
                                                       o
                                                          iH
                                                       i-l  0)
                                                       CO g
                                                       C  (1)
t/)
                                                      •H
                                                      •H
                                                      4-)
                                                       C  4J
                                                       0)  C
                                                      T3  0)
                                                       Cn
                                                       O  0)
                                                       P
                                                       en
                                                      •H
52

-------
Complete automatic operation is accomplished with a magnetic flow meter,
electrical timers, relays, and liquid—level sensors.  Fail-safe in-
telligence systems prevent the unit from operating if any component
fails.  An alarm system sounds a warning of low chemical level and, if
not replenished, the system automatically shuts off.

Figure 11 is a photograph of the FMC Waste Treatment System Model 50-
2000, with major components identified.  An aluminum frame houses
copper-nickel plumbing and shielded electric motors.  Overall dimen-
sions are 239 cm long, 122 cm high, and 203 cm wide, with a total
empty weight of 1135 kg (2500 pounds).   Maximum electrical demand is
12 kva, using three-phase 220- or 440-volt current.  The design
flow capacity for processing domestic sewage is 15 kl/day (4000 gal/
day) at an average flow rate of 9.5 1/min (2.5 gal/min).
                                    53

-------
                              SECTION IX

                      LABORATORY PROCESS STUDIES
The demonstrated physical-chemical waste treatment system was originally
designed and developed as a marine sanitation device to treat sanitary,
galley, and shower wastes onboard ships.  During 2 years of development,
extensive testing and evaluation was done at the laboratory bench and
pilot-plant levels.   A 1000-hour performance test was conducted on a
full-scale preproduction model.  Fresh sanitary wastes having an aver-
age concentration of 800 mg/1 SS and 300 mg/1 BODs were used in test-
ing.  During 29 days of operation, the average removal efficiencies
of SS, BOD5, and TOC were 96, 89, and 79, respectively.

The treatability of marine holding tank wastes was also investigated.
Using actual boat wastes from a marina on Bethel Island, California,
the basic physical-chemical process was evaluated, first in the lab-
orabory and then with full scale-equipment.   A clear process effluent
having a slight blue color was obtained from processing 180 gallons of
holding tank wastes having 1460 mg/1 SS, 850 mg/1 BODs, and deep blue
coloring.  The percent reduction in SS and BODs was 98 and 94 percent,
respectively.  These developmental test results indicated the fea-
sibility of the proposed system to achieve a high level of treatment of
holding tank wastes.

For purposes of this research, a detailed process study program was con-
ducted to evaluate the ability of the proposed system to completely
treat recreational watercraft wastes containing chemical additives.
The effect of specific bactericidal agents on the process was determined.
The removal efficiencies of SS, BOD5, nitrogen compounds, phosphates,
and zinc were investigated and optimized with process modifications.
PROCEDURE

Raw body wastes no more than 3 days old were collected from portable
toilets at construction sites. These fresh wastes ranged from 10,000 to
20,000 mg/1 SS and 6,000 to 15,000 mg/1 BOD5.   Portions of these wastes
were diluted with water and/or fresh domestic sewage to give 1140- to


                                   54

-------
1890-liter  (300- to 500-gallon) batches of waste with SS and BOD5 con-
centration-ranges of 1,000 to 3,000 mg/1 and 800 to 3,000 mg/1, respect-
ively.  These ranges of waste concentration were intentionally chosen
to represent the stronger portion of holding tank samples identified
during the waste characterization program.  Specific chemical additives
(Codes 26 and 40), having zinc and formaldehyde ingredients, were add-
ed separately and/or together to various waste batches.  After
thorough mixing, these treated wastes were aged outside for 2 to 3 days.

Each process run involved the treatment of 950 to 1900 1 (250 to 500
gal )  of simulated holding tank wastewater.  A 3000 1 storage tank
supplied wastewater to the demonstrated full-scale treatment plant.
Influent sewage flow rate was maintained constant during each run at a
range of 3.7 to 7.6 1/min (1.0 to 2.0 gal/min).  Initial startup
adjustments required the setting of timer relays controlling the amounts
of liquid alum, liquid chlorine, and powdered dry chemical  (filter aid and
diatomaceous earth) added automatically to the influent flow.  The
applied vacuum across the rotary filter was manually set by adjusting a
bypass valve on the inlet side of the vacuum pump.  At this point the
equipment was operated "hands off" on automatic control. When the supply
of influent waste was depleted, the equipment processed the remaining
contents of the surge tank and then automatically shut off.  During
operation, composite samples of influent sewage and process effluent
were separately collected and immediately analyzed for characteristic
parameters.  Chemical and power consumption data were recorded for each
run.   During these runs, the aluminum ion concentration (per liter of
sewage) was maintained at 100 mg/1 and the dry chemical concentration
at 1.9 gm/1.  The process pH was 4.0 to 4.2. Previous laboratory
studies had determined that this pH, lower than the conventional alum
flocculating pH range of 5.5 to 7.0, was optimum for maintaining a suit-
able vacuum.filtration rate.   At higher pH values the aluminum hydrox-
ide floe tended to blind the filter fabric.
RESULTS

Average results of nine process runs using simulated holding tank wastes
are given in Table 14.  The presence of zinc and formaldehyde appeared
to have no significant effect on the removal efficiency of suspended
solids, organic nitrogen, phosphates, and turbidity.  However, SOC, BOD5,
ammonia nitrogen (NH -N), and COD removals were reduced.  Wastes con-
taining 1400 mg/1 zinc from treatment with Chemical Additive Code
26 showed a decrease in removal efficiency of BOD5 and COD when com-
                                   55

-------
w

1
w
co

Q
W
w
u
ffi
u
co

EH
hH
D
co
W
co
co
W
o
o
e!
CM


9
<
u
co

rH
 .Q
 rt)

 B
d Wastes0
,
Formaldet
,0
CO
(U
4-1
.
VQ
o
CO
oo
VQ
os
m
rH
i-H
O
1— 1
0
ft
co
oo
ON
OS
in
0
i^
VO
CM

r-l
1
co
co
VO
OS
u->
CM
0
OS
m
CO
0\
co
•d-
0
o
o
M
CM
OO
OS
co
CM
0
OS
vo
n
1-1

rH
60
e
co
CO
>
I-.
m
0
CM

60
25
1
H
O
i— I
O
o-
1— 1
m
m
i— i
00
CM
in
VO
r-i
0
co
CM
r-~
CM
O
r^
r-i
O
CO
CM

r-l
1
&
ff
"Z,
CM
oo
CM
r-l
m
vO
m
t-~
vO
r-i
CO
VO
oo
r~
CO
r-<
0
VD

i— 1
1
f
H
CO
OS
0
1-4
O
in
i— i
o
Os
o
co
0
0
co
CO
OS
o
CM
o
t^
CM
x— \
in
•-)
V— '
Turbiditj
CO
os
m
CD
0
-i
o
r-l
o
U
1
CM

<]
cd




e
o
M
MH
O
C
N
rH
~3>
e

0
0
iH

_f~\
4-1
•H
S

•a
CU
4-J
cd
CD
M
4-1

cu
60
n3
S
CU
cn

rH
O
IH
4J
a
o
O

60
•H
M
3
tn
c
3
^_i

in
to
CD
O
0

04 •
vO
O CM
U
4J CU
e 'o
0 0
!H
in CD
>
Cn -rl
4-1 -P
rH -H
3 73
tn 73
CD <
^1
H
CD ta
Cn o
(fl -rl
^4 S
CD CD
> 43
rt u
rs
CD
73
43
CD

rH
td

O
UH
rH
tn
E
o
o
LO
rH

JJ
•rl
3

73
CD

m
CD

4J

CD
tn
<0

CD
in

rH
o
>H
-P
c
o
o

73
CD
4-1
3
1 — 1
•H

tn
c
•r4
in
3

c •
3 o


in cu
tn 13
CD O
o cj
o
S-l CD
•H
CD 4-1
rH -H
tn 73
-SS
in
rH
m 10
o
14H -rl
o e

tn j5
-P U
rH
3 E
tn o
CD 1-4
a; m
a
                                                                            56

-------
pared to untreated wastes.  The effect of 1500 mg/1 formaldehyde from
Chemical Additive Code 40 was a significant reduction in effluent
quality.  Because of limited data from a single process run at this
high formaldehyde concentration, these results were taken qualitatively.
The significant decrease in organic removal efficiency may be explained
by the contribution of BODs and COD from formaldehyde itself.  Previous
work in this research study demonstrated the biodegradability of
formaldehyde, and the literature1^'-^ reports specific BOD5 values for
various formaldehyde concentrations.  Formaldehyde may readily bind
with proteins present in urine and feces and consequently be removed
with flocculated colloidal matter as a solid phase component.  If the
formaldehyde concentration exceeds the binding capacity of the sewage,
free formaldehyde will be present.  Because of high solubility and
small, symmetrical molecular size, free formaldehyde would not be
effectively removed by carbon adsorption during physical-chemical treat-
ment.  The process effluent would have significant BOD5 and COD con-
centrations from residual free formaldehyde.

Evidence of this formaldehyde effect is given in the process run data.
A portion of simulated holding tank wastes having 1000 mg/1 suspended
solids and 100 mg/1 formaldehyde was processed by the FMC equipment.
The remaining waste was charged with 1500 mg/1 formaldehyde by adding
the recommended dosage of Che.mical Additive Code 40.  After 30 hours
of aging, these wastes were similarly processed.  The BODs, COD, and
soluble organic carbon (SOC) data for influent and effluent samples
taken from these runs are given in Table 15.

Since identical wastes differing only in formaldehyde concentration
were similarly processed, the difference in influent characteristics may
be taken as a measure of the effect of added formaldehyde. The difference
of 1860 mg/1 BODs between the two influent wastes indicates
the BOD5 contribution from 1500 mg/1 formaldehyde.  This result compares
with the calculated value of 1650 mg/1 determined from empirical BODs
data for formaldehydel->.   The difference between the two effluents of
1505 mg/1 BODs indicates a nearly complete carryover of formaldehyde.
Evidence of this same effect is given in COD and SOC data.  These re-
sults indicate that physical-chemical processes cannot readily handle
large concentrations of formaldehyde.
PROCESS MODIFICATIONS

During the process studies, several operating variables were adjusted to
optimize the operation.  The feed concentration of alum flocculant was
increased 50 percent to give an aluminum ion concentration of 200 mg/1.
                                  57

-------



/• \
i-l
1
*~s
o
o
CO





x™\
I-l
DO
^^

a
8





i-i
ff
•*~s
in
a
8





r-4
$
•^
Cri
ir^
4-1
C
cu
r-l
IM
14-1
w
4J
CU
r-l
<4-l
C
r-4
i-l
nj

cu
oi
B~S
4J
01
3
i-l
14-1
<4-l
w
4J
C
1
14-1
I-l
r-4
n)
|
(S
B^
Eluentj
4-l
a
M
<1> C
•d o
>>-H
.£ 4J
a> id ^— .
T» fc r-l
r-l 4J — .
<8 C 60
S -
o>
r^



O
i-i
CO



i-i
ON

in
i^
r-4


o
-*
ON
I— 1

00
r^

in

58

-------
Simultaneously, sodium bisulfate was added as an acidifying agent to
the alum  (aluminum sulfate) solution.  As a result, the process was
maintained more consistently at a pH of 4.0 to 4.5 with significant
improvement in effluent turbidity and phosphate removal.  Dry chemical
mixture was changed from 3:1 to 2.5:1 parts filter aid to activated
carbon*, and its feed rate was increased 50 percent to 4 gm/1.  This
resulted in improved SOC, BODs, and color removal.  The average process
rate was decreased from 7.6 to 4.5 1/min with general improvement in
operating efficiency.  At this point, the proposed physical-chemical
system had demonstrated its ability to reduce the suspended solids and
phosphate concentrations of simulated holding tank wastes by 90 percent,
as well as control the coliform count of the process effluent at a
level below 20 MPN/100 ml.  Average BODs removal was 76 percent, while
total nitrogen removal was only 27 percent.
AERATION

In an attempt to improve the removal efficiencies of nitrogen compounds
and BODs, the effect of short term aeration of wastes before treatment
was investigated.  Fresh, raw body wastes were diluted with water to a
suspended solids concentration of 2150 mg/1.  Equal portions of this
waste were separately charged with zinc and formaldehyde chemical
additives at their recommended dosages, mixed together, diluted 50 per-
cent with water, and aged for 16 hours.  No pH adjustment was made of
the sewages.  This chemically treated waste was aerated for 24 hours at
2.0 cfm with mild stirring.  Grab sewage samples were taken after
various aeration times and analyzed for critical diagnostic parameters.
Analytical results indicated no significant conversion of organic
nitrogen to ammonia by bacterial hydrolysis while TOC, SOC, and BODs
concentrations were unchanged.  It was concluded from these studies
that short-term  (2 to 24 hours)  aeration of chemically treated holding
tank wastes at pH 7.3 had little or no effect on organic removal.
Ammonia removal by aeration of wastewater at an adjusted pH of 10 to 12
was not tried.  The literature   reports this pH range to be most
effective for ammonia removal by aeration.
CHLORINATION

The effectiveness of increasing amounts of available chlorine added be-
fore physical-chemical treatment was investigated using pilot-plant
test equipment.  Chemically treated wastes prepared for aeration
*A low surface area, large particle size activated carbon, Nuchar KD,
 was used to minimize the strike through of carbon into the process
 effluent during vacuum filtration.

                                   59

-------
studies were pretreated with increasing amounts of chlorine added as a
hypochlorite solution  (70 percent available chlorine) by means of an
adjustable feed pump.  Influent sewage flow rate was maintained at 5.7
1/min  (1.5 gal/min).   Analysis of influent and effluent samples indicated
no significant increase in removal efficiencies of BODs , COD, total
nitrogen  (T-N), and ammonia nitrogen (NH3-N)  when treated with chlorine
concentrations of 0 to 200 mg/1.  Effluent samples indicated no measur-
able free chlorine.  These results agree with the literature12 which re-
ports that chlorine oxidation of concentrated wastes having high COD
values is relatively ineffective and uneconomical.  It was concluded
that prechlorination would only be employed for bacteriostatic control
and not used as a process method for reduction of organic matter.

Postchlorination of residual organic compounds present in the process
effluent was investigated as a method of increasing the overall removal
efficiencies of BOD5 and total nitrogen (T-N).  Hypochlorite oxidation
of urea was characterized in the laboratory by following the rate of
SOC removal as a function of time at different urea and chlorine con-
centrations.  A pseudo first-order rate constant of 0.13 min"1 was de-
termined from urea concentration of 330 mg/1 at pH 7.7, reacted at 25°C
with 1500 mg/1 available chlorine.  Similar rate studies on actual
process effluent having 66 mg/1 SOC, 44 mg/1 T-N, and 39 mg/1 BOD5 gave
a rate constant of 0.006 min   calculated from SOC removal data.   The
initial chlorine concentration was 550 mg/1.

Chemically treated wastes prepared for previous aeration studies were
processed by the demonstration system.   The resulting effluent was
separated into four equal volumes,  charged with varying amounts of cal-
cium hyprochlorite, stirred slowly for 40 minutes, stopped with sodium
sulfite, and analyzed for diagnostic parameters.   These results,,  given
in Table 16, indicated that significant reduction of residual organic
matter can be accomplished by postchlorination of process effluent.
With 2725 mg/1 available chlorine reacting for 40 minutes, the overall
removal efficiency of T-N was increased f3:om 25 to 73 percent, while
NH3~N removal increased from 29 to 66 percent.  TOC and SOC removal
efficiencies were increased from 70 to 86 percent and 57 to 76 percent,
respectively.  These results indicated that BODs removal would also be
significantly improved.  Based on SOC data, the calculated pseudo first-
order rate constant was 0.010 min  , and the reaction half-life time
was 69 minutes, meaning that 50 percent of the SOC remaining in the
effluent would be removed in 69 minutes.  A retention time of 3.4 hours
would be required to remove 87.5 percent of the SOC originally present.

                                  60

-------
                  Table  16.   EFFLUENT CHLORINATION DATA
Parameter
Available Chlorine Feed (mg/1)
Reaction Time (min)
TOC (mg/1)
SOC (mg/1)
T-N (mg/1)
NH3-N (mg/1)
Influent
0
	
1,140
760
704
502
Effluent
A
0
0
340
326
526
355
Effluent
B
745
40
272
252
395
322
Effluent
C
1,490
40
210
219
289
233
Effluent
D
2,725
40
165
183
193
170
 It was decided that postchlorination of process effluent would be
 piloted  for improving the overall removal efficiencies of BOD5 and T-N.
 A simple chlorination system consisting of a chlorine feed pump and
 retention coil was assembled.  Using a positive displacement pump/
 process  effluent from the treatment unit was moved at a constant rate
 of 1.9 to 5.7 1/min  (0.5 to 1.5 gal/min), while a sodium hypochlorite-
 sodium hydroxide solution was added automatically with a precision
 metering pump.  Base was used to raise the process PH from 4.5 to
 6.0-9-0.   The chlorinated effluent flowed through a 2-inch PVC pipe
 retention coil, consisting of 26-foot pipe loops, having a total cap-
 acity of 107 gallons.  Retention time in the coil was maintained con-
 stant at 60 to 120 minutes by controlling discharge flow rates.

 Preliminary testing of the postchlorination system was conducted using
 simulated holding tank wastes charged with recommended dosages of zinc
 and formaldehyde chemical additives.  After normal processing of sewage
by the demonstration waste treatment system, the effluent was treated
with 2000 to 3000 mg/1 available chlorine and retained for 40 to 150
minutes.   Samples of chlorinated effluent were dechlorinated with
 sodium thiosulfate and analyzed for various parameters.   Operating
difficulties were experienced in controlling the process pH and flow
rate.   BODs and COD results were incomplete because of lost samples
caused by interference from excess,  unknown amounts of sodium thio~
sulfate.   Overall removal efficiencies of TOC and SOC were increased
approximately 10 to 15 percent,  while T-N and NH -N removals were in-
creased 50 to 60 percent.  These qualitative results demonstrated that
the proposed system,  coupled with postchlorination, indicated an
ability to process chemical holding tank wastes to a level of treatment
approaching 90 percent removal.
                                  61

-------
ZINC REMOVAL

Since watercraft wastes may contain significant amounts of zinc (50 to
1500 mg/1) which is known to be toxic to most microorganisms, its re-
moval was a goal of complete waste treatment.  Laborabory studies de-
termined that zinc was quantitatively removed from solution as a zinc
hydroxide-carbonate precipitate when reacted with sodium carbonate at
pH 9.5.  Actual process effluent containing 1400 mg/1 zinc was adjusted
to pH 9.5 with sodium carbonate, and after mild stirring for 5 minutes,
the precipitate was removed by filtration, giving a clear filtrate having
less than 0.3 mg/1 zinc determined by atomic absorption analysis.
Solubility studies of zinc hydroxide carbonate showed a significant pH
dependence with a minimum solubility at pH 9.5.   At pH 8.5, the residual
zinc content of the filtrate was 4.2 mg/1.

Using these characteristics, a zinc removal system was designed to treat
normal process effluent.  Basic components were a chemical feeder for
addition of base, a reaction coil where the zinc precipitate develops
and flocculates, and a filter to separate the solid precipitate from
the liquid effluent.  For efficient utilization of equipment, the zinc
removal process was incorporated into the postchlorination equipment.
The same metering pump and reaction coil were used.   Laboratory studies
determined the proper amount of sodium carbonate or sodium hydroxide to
be added to the sodium hypochlorite solution that, when added to the
process effluent, would give a chlorinating process pH of 8.5 to 9.5,
with a hypochlorite concentration of 2700 mg/1.   Process flow rate was
maintained constant at 1.9 to 5.7 1/min (0.5 to 1.5 gal/min)  by means
of a positive displacement pump.  From the outlet of the coils, the
treated effluent was filtered through a GAF pressure bag filter con-
taining a polyester filter bag having a rated porosity of 5 microns.
Preliminary testing showed that a constant filtration rate was main-
tained during the short term tests if the filter bag was originally
precoated with diatomaceous earth.

This equipment was evaluated during the process run studies operating
on simulated holding tank wastes.  Approximately 1500 1 of aged wastes
having a zinc concentration of 750 mg/1 were processed by the demonstra-
tion waste treatment system and the resulting process effluent was
treated for zinc removal.  Composite samples of effluent before and after
treatment were analyzed for total zinc by the atomic absorption method.
At a final effluent pH of 9.9, the zinc concentration had been reduced
from 268 mg/1 in the original process effluent to 1.5 mg/1, demonstrat-
ing the system's ability to remove over 90 percent of the zinc
originally present.
                                  62

-------
                               SECTION X

                         PROCESS FIELD TESTING
Phase II of this program involved extensive field testing of the full-
scale preproduction Model 50-2000 FMC Waste Treatment System.  The
Lake Mead National Recreational Area, Boulder City, Nevada, was selected
as the demonstration site after a thorough survey of marine locations
in all areas of California and Nevada.  Test equipment was transported
to the site in a 40-foot demonstration trailer owned by FMC Corporation.
After simple hook-up to waste supply and electrical power, operational
testing began.  Pumpage from watercraft holding tanks was processed
daily for a total of 8 weeks.  Analytical tests were performed to
describe the degree of treatment and data were recorded to define the
operating costs.
SITE SELECTION AND DESCRIPTION

A survey was conducted of 46 public and private marinas having nearly
18,300 boats located in freshwater and saltwater in areas of California
and Nevada.  Each marina was described by the following characteristics:
number of boats, average length, number of boats with onboard toilet
facilities, number of boats with waste retention/recirculating systems,
existence of boat pumpout facilities, means of waste disposal, avail-
ability of electrical power (three-phase 220 or 440 volts), and will-
ingness to cooperate in a demonstration program.  The specific
characteristics of 16 marinas involved in this survey as well as a waste
characterization program were given previously in Table 3, Section IV.
A summary of survey results from all 46 marinas is given in Table 17.

The results of this marina survey indicated low percentages of boats
equipped with waste retention / recirculating systems and few pumpout
facilities, especially at saltwater marinas.  All freshwater locations
covered in this survey had existing regulations prohibiting overboard
discharge of sanitary sewage.   Therefore, the percentage of boats with
waste retention systems was significantly higher than at saltwater
marinas.  Similarly, the pumpout frequencies and waste volume flows
were appreciably higher.  In Southern California, the larger coastal
                                  63

-------
•a
H
rH
A! 4-1
0) 3 0
(U Q 3
IS ft O
IT) ft
4-1
O
H
in
4J Ol
3 -H
0 4J
ft -H
6 rH
3 -H
ft U
id
fa
w en 4J
cn <3 -H
id -H o
SH U Id
0) rH ft
> 0 id
fiC DC U
1 i £
•H O
S 0) -H
4-1 4-1
4-1 tn c
S3 id a)
0) S 4-1
U 01
>H »;
0)
ft
4-> en
C X! 4-i
Ol 4-1 01
0 -H rH
H S -H
0) 0
ft EH
0)
tn 43
id 4-1
SH Cn
01 a
> 
rH







0\°
CO
CO
g j_l
rH ^~*
d £

•*
cn
o
^,
rH
rH



U1
rH


SH
0)
4J
i
4-i
rH
id
W
rH
id
rH IT1
0 0
0 0
in "">
^ *»
CSl VO




rH
CM




rH
i — i id
cn
in
cn 1/1
CM
*™ "*




cA°
^D
CM







o\°
CM
 >
s <
in
4-1
id
O
XI

T3
0)
SH
O
O
e
0
0
rH

4-1
tn
(0
0)
rH

4-1
id

•a
id
r;

TIJ
0)
K*^
0)
^
^
5
W

<0
C
-H
j_l
id
S

r^
0
id
H
id
boats, and houseboats.
rH
•iH
id
in

^
tn
4-1

O
XI
SH
0)

O
ft

rQ
0)
rcj
3
rH
O
c
•H

tn
4J
id
O
XI

•4H
O

S-t
0)



c

rH
id

EH
XI
ring peak boating season estimated from marina pumpout
3


y
0)
01


rj
ft

U
0)
4-1
tn
id
3

4-1
3
O
ft

3
ft

UH
0

3
O
rH
m

01

3
H
O


rH

£
EH
U
4-1
•H
O
Id
ft
id
o

Cn
C
-H
13
rH
O
43

0)
4J
in
id
3

4-1
id
o
XI

01
Cn
id
ti
01
£>
id

T3
C
id

t>i
u
C
11
3

0)
14H

regulations prohibiting the overboard discharge of

en
c
•rH
4-1
0)
• H
X
0)
13
id
r^

•O
01
>1
0)
^
u
p
in

tn
(3
O
• H
4-1
IT)
O
O
rH

^
0)
4-J
td
3

w
01
SH
14H

rH
rH
rc£
T3































•
tn
0)
4-1
CO
id
3

t^i
>-i
td
4J
•H
§
tn

number of boats in freshwater and saltwater.

0)
c1,
4-1

O
4J

F>1
rH
rH
id
C
O
•H
4J
M
O
ft
O
SH
ft

T3
0)
4J
_f|
Cn
•H
Ol
3

tn
4-1
rH
3
10
0)
^_)

0)
Cn
id
M
01
*^C
0)
                                       64

-------
marinas reported less than 1 percent boat usage of pumpout facilities.
At Marina del Rey, California, one fuel dock operates the only pumpout
facility for 21 separate marinas having a total boat population of
nearly 6000.  The reported frequency of individual boat pumpouts during
July and August (peak season months) was only 18 to 25 times per week.
The only significant volumes  (greater than 500 gal/week) of watercraft
waste pumpage occurred at marinas on large freshwater lakes where no-
discharge ordinances were enforded.  Marinas at Lake Mead and Lake
Shasta reported the largest watercraft waste flows of 7.6 to 17.0 kl
(2000 to 4500 gal) per week.  Lake Shasta was excluded as a potential
demonstration site because three-phase 220-volt current was not
available at the marinas willing to cooperate in the demonstration
program.

Lake Mead National Recreation Area, under the jurisdiction and adminis-
stration of the National Park Service, U.S. Depertment of Interior, was
chosen as the field demonstration site.  Located 25 miles from Las
Vegas, Nevada, this 3000-square-mile area encloses two large lakes,
deserts, canyons,  and plateaus.  The mild, arid climate permits year-
round enjoyment of over 5 million visitors each year, making it the
fifth most active National Park in the United States.  Lake Mead, 115
miles long with 550 miles of shoreline, was created by the construction
of Hoover Dam.

Lake Mead has six marinas of varing size, with moorings for approxi-
mately 2500 boats.  Although power boating and sport fishing are the
dominant activity, sailboats compose 35 to 40 percent of the boat pop-
ulation.  Conventional pontoon houseboats operate on Lake Mead only as
power boats, since no long-term onboard living is permitted.   Trailered
boats contribute significantly to the load factor of Lake Mead.  During
the summer season, the count of trailered boats entering the park
reaches 20,000 per month.  Although the average boat length at Lake
Mead is only 16 feet, nearly 50 percent (1200)  of the moored boats have
waste retention systems, with an average 50 gallon holding capacity.

A no-discharge regulation for sanitary wastes has been in effect and
enforced at Lake Mead for 7 years.  Pumpout facilities, located at
each marina and boat harbor, are owned and maintained by the National
Park Service.  Use of the facilities is free, with self-service by the
boat owner.  Each pumpout station consists of a floating platform
containing an electric-driven diaphragm pump, suction hose,  700-gallon
waste storage tank, freshwater flush line, level controlled transfer
pump, and piping system leading to shore.   Special adaptors and pipe
connectors are supplied to secure the pumpout hose to the boat's waste
deck fitting.  It is estimated that during the summer months a total of
15,000 liters (4,000 gallons)  of watercraft wastes are pumped each week.
                                  65

-------
On-shore wastewater treatment involves oxidation-evaporation lagoons.
Sanitary and galley wastewater from each marina is combined with pump-
out wastes and transferred by lift pump to remote oxidation ponds.
Sewage from trailer parks, campsites, and resident motels is also
pumped to lagoons by means of a common collection system.  Three lagoon
systems serve Lake Mead, each receiving 76 to 190 kl  (20,000 to
50,000 gal) per day.  Periodically these ponds are dried, and the
accumulated solids are removed.   At this date, three new waste treat-
ment plants offering secondary treatment are being planned to replace
the oxidation ponds, which cannot provide adequate treatment of the
Park's increasing wastewater flows.

Lake Mead Marina, located near the western entrance of the Park and 4
miles from Boulder City, Nevada, was chosen as the physical location
for the test equipment.  Being the largest and most visited marine in
the park, it provided the largest volume of watercraft wastes.  The
marina moored 450 boats averaging 28 feet in length, and 340 boats had
waste holding systems.  Two large excursion boats, making daily trips
to Hoover Dam, also operated from this marina.  The average weekly
flow of 5700 liters (1500 gal) of pumpage came primarily on Friday
through Monday.  To increase the total volume of pumpage available
for demonstration processing, boat wastes pumped at a nearby marina
were truck-hauled to Lake Mead Marina and deposited for treatment.  This
source supplied an additional 1900 liters (500 gal) per week.
EQUIPMENT INSTALLATION

The demonstration system, housed in a 40-foot trailer, was transported
to Lake Mead Marina and located in the overflow parking section 100
feet from the water.  This equipment is pictured in Figure 12.  Adjacent
to the trailer was an electrical utility stand having three-phase 220-
volt current, junction box, and power meter.  Direct connection of
leads to this junction box supplied the necessary power to the test
equipment.  A 3000-liter (800-gal) supply tank placed ahead of the
trailer was connected to the waste supply line coming from the floating
pumpout station.  This line was normally connected to a lift pump.  A
waste supply line and centrifugal transfer pump were attached to the
holding tank outlet and the sewage inlet of the trailer.  A freshwater
line was connected to the trailer to supply a laboratory faucet and
utility hoses.  A garden hose joined the effluent outlet located under
the trailer with the suction side of the existing sewage lift pump.  No
marina wastes, only boat wastes, were supplied to the test equipment.
To prevent the possibility of overflow from the holding tank, a bypass
valve and line were arranged to allow direct flow of wastes trom the
pumpout station to the lift pump, except when specifically directed to
the tank.
                                  66

-------
                                                 .*••-
;    o
~    a
    10
                                                                  •rH

                                                                  3
                                                                  !
                                                                  (0
                                                                  0)
                                                                     T3
                                                                  0)  T3
                                                                 r-(  (fl
                                                                 •H  0)

                                                                  2  s
                                                                 -P  0)
                                                                 O  J
                                                                 •H
                                                                 4-1  4J
                                                                 0)  (0
                                                                 M
                                                                 4-1  T)
                                                                 W  0)
                                                                 C  4J
                                                                 Q  03
                                                                 6  O
                                                                 0)  O
                                                                 Q  r-H
                                                                i-H

                                                                 0)
                                                                 Cn
                                                                •H
67

-------
OPERATIONAL PROCESSING

After functional testing of mechanical and electrical systems, the
demonstration equipment was operated on water while calibration curves
of feed pumps, flow meters, and level controls were confirmed.  Using
the trailer laboratory facilities, composite waste samples were analyzed
for suspended solids, pH, color, and buffering capacity.  With this
information, process chemical solutions were prepared at appropriate
concentrations, and dry chemical feed rates were calculated for various
influent flow rates.  Actual wastes were then processed under different
conditions to establish in general the optimum degree of treatment
based on visual inspection of the effluent.  The zinc removal post-
chlorination equipment was pressure tested and the base requirement for
pH control determined.  This preliminary testing required two men for
3 days.

Operational processing began on August 22, 1973 and continued for 8
weeks to October 16.  Because of heavy weekend activity, test equipment
was normally operated from Thursday through Monday, 5 days a week, for a
total of 35 operating days.  During this time, 42,000 liters  (11,000
gal) of watercraft wastes were treated by the demonstration equipment.
A daily volume of 950 to 1900 liters (250 to 500 gal) was processed at
an average rate of 4.1 1/min (1.1 gal/min).  Auxiliary zinc removal
postchlorination equipment was operated for 14 days.  Samples of in-
fluent, effluent, and solid filter cake were regularly collected for
analysis of various parameters, and records were kept of operating
conditions and chemical consumptions.  One technician monitored the
equipment, collected samples, and recorded operating data.

A standard procedure was followed each operating day.  Wastes accumu-
lated in the storage tank of the pumpout station were transferred
ashore to the 3000-liter holding tank.   Records were made of total
waste volume, chemical feed rates, chemical levels, and time.  Once
the control panel was set to automatic operation, waste was trans-
ferred from the outside holding tank to a 340-liter (90-gal) supply
tank equipped with level controls.  Influent rates to the demonstration
system were manually adjusted to 3.8 to 4.6 1/min  (1.0 to 1.2 gal/min)
as indicated by a magnetic flowmeter and recorder.  Primary and second-
ary vacuums of filtration equipment were adjusted to 28 to 18 cm (11
and 7 inches) of mercury, while air-blow pressure was set to maintain
proper removal of filter cake at the "wire doctor blade."  At this
point, the process was left to operate automatically and unattended.


                                  68

-------
Every 20 minutes, samples of influent waste and process effluent were
taken and properly composited.  Grab samples for coliform analysis
were collected in sterile bottles containing sufficient sodium sulfite
to reduce any free chlorine.  Solid filter cake samples were sealed in
special containers after removing a portion for total solids analysis.
All samples were refrigerated at 4 C.  Process control was monitored
by periodic analysis of effluent pH, turbidity, and total chlorine.
When processing was complete and the equipment had automatically shut
down, records were again made of chemical levels and time.  Total
solid filter cake production was weighed and recorded.  Volume of
process effluent was read from a recording flowmeter in the effluent
line and total power consumption was taken from a kwh-meter.

Zinc removal and postchlorination auxiliary treatment used a reactant
solution consisting of 6 gallons of water, 6 gallons of 14 percent
sodium hypochlorite, and 1600 ml of 50 percent sodium hydroxide.  A
precision metering pump delivered this solution at 120 ml/min to
process effluent that was pumped at 3.8 1/min through reaction coils
and pressure filter.  Under these conditions, the available chlorine
content was 2660 mg/1 with a retention time of 90 minutes and a process
pH of 9.5.  The metering pump ran simultaneously with a positive
displacement pump supplying effluent for treatment.  In this mode of
operation, effluent samples were collected after pressure filtration.
Chemical consumption and process rate were recorded at the end of
operation.
                                 69

-------
                             SECTION XI

                         PROCESS EVALUATION
Evaluation of the demonstration physical-chemical system was based on
operating results determined from analysis of samples taken each
operating day during the 8-week test period.  Chemical and power
consumption data were used to determine cost of operation.  Process
removal efficiencies for various chemical and biological parameters
were determined for each of the 35 operating days.  Average operating
results were calculated for comparative evaluation of the effectiveness
of postchlorination and zinc removal processes.
SAMPLE ANALYSIS

Composite samples of influent waste and process effluent collected each
operating day were analyzed for SS, VSS, TS, TVS, TOC, SOC, BOD5, COD,
T-N, NHa-N, T-POit, pH, conductivity, and turbidity.  Grab samples of
solid filter cake collected twice a week were analyzed for TS, TVS,
BODs, coliform, and zinc.  Influent and effluent grab samples taken
on the same 2 days per week were analyzed for zinc, formaldehyde, and
coliform.  Sample preservation and analytical procedures were done in
accordance with EPA's Methods for Chemical Analysis of Water and Wastes .
Zinc and formaldehyde analyses were performed by West Coast Technical
Service, Inc., Cerritos, California.  Atomic absorption analysis of the
acid dissolved sample ash was used for zinc determination, while for-
maldehyde was determined colorimetrically by the chromatropic acid
method-^.  BODs and COD analyses were performed by Clair A. Hill and
Associates, Redding, California, and the remaining analytical work was
done by the Environmental Engineering Laboratories, FMC Corporation,
San Jose, California.  Samples were air-transported within 6 hours to
respective laboratories where analyses were immediately begun.

Preliminary BODs determinations on influent waste samples gave evidence
of toxic effects of zinc and other chemical contaminants.  BODs results
varied significantly as a function of waste sample dilution.  Dilution
samples having a greater volume percent of waste consistently gave lower
                                  70

-------
BODs results.  On diluted seeded samples containing 0.5, 1.0, and 5.0
ml of watercraft waste per 300 ml, the BODs determinations were 1400,
830, and 330 mg/1, respectively.  Similar results were obtained with
different domestic sewage seed materials after strict sample pretreat-
ment to remove any oxidants.

It was concluded that toxic effects of zinc and other possible contami-
nants present in the wastes were the cause of the variances in BODs
results.  The zinc content of waste samples from Lake Mead averaged 340
mg/1 with a range of 8 to 1114 mg/1.  Brown and Andrew^ reported the
suppression of BOD5 results by the effect of zinc.  For domestic sewage
containing 50 mg/1 zinc, the measured BODs was 45 percent of the true
value.  With as little as 5 mg/1 zinc, the variance was nearly 30 per-
cent between true and measured BODs values.

In order to minimize the toxic effect, all BODs determinations on
influent watercraft wastes and solid filter cake were done on highly
diluted samples having 0.1 to 0.5 ml of sample per 300 ml.  Average
results of duplicate samples having the highest dilution that showed
at least 1 mg/1 residual dissolved oxygen (DO) and a minimum depletion
of 2 mg/1 DO were chosen as most reliable.

A glucose-glutamic acid standard solution was analyzed for BODs to check
the quality of dilution water, the effectiveness of the seed, and the
analyst's technique.  The resulting mean BODs value of 229 mg/1 compared
very well to .the reported standard value of 218 mg/120 when using- a
fresh, settled sewage seed.
ANALYTICAL RESULTS

A complete record of analytical and process data for each day of
operation at Lake Mead is qiven in Appendix E.  Analytical results
characterized daily composite influent and effluent wastewater samples
with 17 diagnostic parameters including chemical, physical, biological,
and microbiological tests.  Process data included daily chemical  and
power consumptions, process rate, and total processed volume.

A summary of analytical results from samples collected the first 21
days of normal operational processing is given in Table 18.  Zinc
removal postchlorination equipment was not operated during this time.
A broad range of influent waste concentrations were processed to a high
degree of treatment.  Suspended solids, BODs, and COD removals all
averaged 97 percent.  While total-phosphate (T-POi,)  was nearly quantita-
tively removed (98 percent average), nitrogen compounds received little
treatment as evidenced by total-nitrogen (T-N) and ammonia nitrogen
(NH3-N)  removal efficiencies of 30 and 25 percent, respectively.  Zinc
                                  71

-------
rtj.
 O
 z
 H

 S
 M
 H


 §
 S

 to
 EH
 ij
 D
 W
  •8
  EH
4J
C
tu
o
M

C
3
UH
14H
W

U)
U)
CU
(J
o
^
CU









a
CU
in
to
S
4J
c
CU
3
rH
14H
C
H








CU
4-1
CU

fB
t.
rfl
CU



(I)
cn
rfl

tu
>
<
nimum
•H
S


§
E
•H
X
1



tu

fO

(U

g
g
•rl
C
•H
a


c
E
•H
X

S


tu

(O

01

<3















r^ tr» I i incNf^r^omco i
en t7^ 1 1 fji CO CJ^ 0*1 ro tN o^ 1


OlBr>O'3'rHrHCN'3'aitNO
rH rO rH rH i-H ^ i-H O • •
• . rH rH O "*
O O V




oincyi^i^cooooinoco
romr-tNCOr>i-ir-cNO • •
H « . ro H ro ro ro TJ
O O rH





in co o ^o CN *>o ^* *•}* o ^-i1 o ^J1
inrHinrHrotNi-HT^'i-H • •
• i i-H CN tN in T
o o

OOrorjiOinOOOrOkOin
^Q^*CNOino^OCNrocor~ •
fOCNt.cN iHCNCNrH F>
o o
rH




OOVDVDOOOOOOOCO
CNCNCO^CCTirOOrHCOCOrH .
^J* f**l • • if) O4 ^O O ^* *^ 0^ 00
» 0 0 -
r^- in fH co ^f
rH




ominoo<»ooooorH
fN <~H ro CN P"* ^* O O ^* (J^ ^D *
^f^l • «^r-H^'v£rO(N(NOO
^ o o •>
i-l >-t tT1 rH

r-\ t— t rH i— 1 rH rH rH rH i— t
01 O^ ^^n **"^ 01 01 0^ 01 0* 01 01
ee-^^ssseees








z •»
1 0
to COUOQDZ"Oi
tocoto>oooo i a i ac
to>EHEHEHCOOfflEHZEH Q<



1
1


o
o
CO
ro



o
o
tN
*«
^




o
o
o
^
in
o
in
CN
fc
CN




o
o
ro
*
"•31





O
m
rH
^
ro

S
S,

^i
4J
• H
J>
•H
4J
O
P
-o
c§



VD
CO


ro




in
v^







rH
CN



O
o
i-H






O
in
CN







in
^
rH



EH




^i
P
•H
T)
•rl
A



vO
m


*>




ro
in







1— 1
CN




CN







CTi








CO
rf




rH
I









U
C
•rl
N



in
r~


•
o




(-»
•
ro






tN
•
tN


00
•
rH






CM








0^
•
00



i-H
I

Q)
*O
^
£
0)
T3

(rt
&



i
i


ro
V




O
rH







^




in
o
rH
X
ro
CN



CO
O
H
X
CN
*£>



CO
O
rH
X
r*^
rH
i-H
g
O
o
i-H
Z
Qj
S5
*— '

e

0
4H
•H
i-H
8










0
o
o
CN

o
in .
c
rH 0
CU -H
'O 4-*
O rfl
S C
•H

i U
tO 4-1

c R
tu
Brl
O
rfl
0) H

£ >

•P CU
in M
rfl
S 0
C
fj -H
S N
)H
en O

•H
t/1 4-*
3 C
cn E
C 4-3
•rl (0
tn cu
in rl
tu -P
o
0 >i

ft rfl
• H
T3 rH

rfl 'x
T) 3
C (0
rfl
P O
to z
rfl
ro
tn
r-l
(U
CU
•P
ft
tu
to
tN
48
.p
01
p
tn
3
telj

CN
tN

E
0
14-4

w
^1
rfl
'O

in
in
cu
o
O
rl
ft

(U
4J
rfl
rfl
ft
tu
in

H
CN
U)
•P
C
0)
in
cu
ft
cu
M

rfl
•P
rfl
't?

rH
rfl
O
•rl
4J
^i
H
rfl
C
K£
J3
                                                           72

-------
CTl
 01
rH

•8
4-1 rH
C rd
CD >
O O

CD CD
Pi K

C]
4J
C
CO
3
MH
MH
W

Cn
co
o
0

CM









^Q
0)
i)
en
(B
3

4J
C
CD
3
rH
MH
C
M









M
CD
4-1
CO

ft)
(0
CM




CO
en
m
^_i
CD
>

nimum
•H
S



5
g
•H
X

S


CD
Cn
rd

CD
1
§
g
•H
C
•H
S




g
•rH
X
(0
S

CD
Cn

^
CD
j>
<£

















CTI CTI i j in vf> in vo vo
CTI CTi t 1 CTt 1 C7i CTi v£>


OOr-^DCNCOCOCNCN
• • ^ O rH PI
in rH . •
0 O





cricNo^co^otno
PlrHLnCNCNCTl^inPl
. . rH in rH CN
r-\ 0





CTicNrHPicor-ocoin
rH •rHrH-sfPlminCTI
•d1 • i CN
rH O

ooirirHOinoOrH
CTlrHCNrHrHlflinOCO
co v£> • • in «3* PI
0 O
rH




oor~ooooooo
OOCTiinP>CNCOOOkD
om • . ^r PI CD r~- PI
» » 0 0 ^ -
P) CN rH PI P)




oor^pimoooo
vOCTiPlCNOOinOrHCO
Ovo • • 00 ' — ir^mcN
-^00 -
CN rH t rH

i-H rH rH rH rH rH rH
CP Cn *— » - — Cn Cn Cn Cn Cn
gEoOOOO 1
co>E-ifHE-|to(jeaEH



PI O 1 1
^D CTi | 1


rH CN CN O
V • • O
O PI CO
V ••
in




in o o o
rH . . O
CN PI rH O
rH ••
CO
rH



un co PI o
CO « • O
O CO 00
w
CN
rH
CO O PI O
PI ^r • o
[*^ rH
^
CN




O ID O O
CTi Is- • O
CN rH CTi m
^
PI




o ^r rH o
P) O .0
CN i— 1 00 O
^
PI

r— t I-H ^
\ \ o
Cn Cn X
g E E

-^
4J
•H
•H
4-1
O
2 j- 3
1 O t3




vD
CTi


O
in





O
rH







*3*
•
r^.


in
CN
rH






O
oo
CN






O
03
rH



3
£-H
•"3




4J
•H
T3
•rH
J"J
|



CN
CTi


O
H





O
t
CN
rH





>£
t
PI


PI
r-H







in
lO







IX)
*-p




rH
Cn
_§








O
C
•H
N



rH 1
r- i


O P)
• V
rH





PI in
•
in






00 PI
•
CN


rH Vfl
• 0
'sj' rH
X
CN
I



in co
. O
r- H
rH X
in
P)


CO
CO 0
• rH
cn X
^
rH
rH
rH
X. O
Cn O
g rH
2
CD CM
T) &
>i ~-
(D E
"O SH
rH 0
rd MH
a>H
rH
0 0
fc, U
                                                                                                                                             CJ
                                                                                                                                            o
                                                                                                                                             CN
                                                                                                                                             m
                                                                                                                                              I
                                                                                                                                             O
                                                                                                                                             PI

                                                                                                                                             •p
                                                                                                                                             CO

                                                                                                                                             CD
                                                                                                                                             O
                                                                                                                                              C
                                                                                                                                              CD
                                                                                                                                             4J
                                                                                                                                              CD
                                                                                                                                             CO
                                                                                                                                             4-1
                                                                                                                                             3

                                                                                                                                             •r-l
                                                                                                                                             g
                                                                                                                                             CO
                                                                                                                                             CD
                                                                                                                                             Cn
 10


 0
•r-l
4J
•H
T3
 C
 0
CJ



 0
•H
•p
 rd
 C
•H
         CD
         a
         o
                                                                                                                                                     VD
                                                                                                                                                     S
         CD
         4J
                                                                                                                                                      CO
                                                                                                                                                     CO
                                                                                                                                                      O
                                                                                                                                                      )H
                                                                                                                                                     MH
         T3

         cn
         w
         CD
         o
         0

         ft

         0)
         4J
         (0
                                                                                                                                                      ft
                                                                                                                                                      CD
                                                                                                                                                      cn
                                                                                                                                                     4J
                                                                                                                                                     c
                                                                                                                                                     a>
                                                                                                                                                     cn
                                                                                                                                                     CD

                                                                                                                                                     ft
                                                                                                                                                     CD
                                                                                                                                                     (0
                                                                                                                                                     T)
 CJ
•H
4J
         (0
         C
                                                                             73

-------
and formaldehyde removals averaged 56 and 75 percent, respectively.
Effluent coliform content was consistently below 10 MPN/100 ml.

The results of zinc removal and postchlorination processing are given
in Table 19 which represents 14 days of processing.  Postchlorination
resulted in a significant increase in removal of nitrogen compounds.
T-N and NHs-N removals were nearly doubled to 66 and 63 percent,
respectively.  Suspended solids, BODs, COD,  and T-PO^ removal efficien-
cies all averaged greater than 95 percent.  Average effluent turbidity
was reduced from 21 to 10 JTU* with the additional filtration of the
auxiliary treatment.  Postchlorination had no significant effect on
removal of formaldehyde because of its very high break-point chlorine
demand.  Removal of zinc was increased to 92 percent with auxiliary
treatment at pH 8.5 to 11.0.  Optimum removal efficiency was attained
at pH 9.5.

Grab samples of solid filter cake discharged from the rotary vacuum
filter were taken during 21 days of operation and were individually
analyzed.  The average results of these tests are given in Table 20.
Total solids (TS) averaged 31.7 percent and total volatile solids  (TVS)
averaged 10.7 percent.  Dry filter cake production averaged 13.2 kg/kl
(110 lb/1000 gal) based on effluent volume.   Approximately 4.4 kg of
this cake were sewage solids with the remaining 8.8 kg being filter aid
and diatomaceous earth.  The zinc content of the cake averaged 1.5 mg/g
of dry solids.   Jnfluent wastewaters had an  average zinc concentra-
tion of 45 mg/1.  BOD5 determinations on fresh, wet cake samples
averaged 53 mg/g of dry solids.  A material  balance over the process
showed fair agreement between total zinc and BODs contents of influent
wastes compared to total effluent and filter cake contents.  A more
accurate balance may have been achieved had composite cake samples
been collected instead of grab samples.

           Table 20.  CHARACTERISTICS OF SOLID FILTER CAKE
Parameter
TS
TVS
BODs
Coliform
Zinc
(%)
(%)
(mg/gm)
(MPN/gm)a
(mg/gm)
Average
31.7
10.7
53
65
1.5
Maximum
34.6
12.9
105
340
5.4
Minimum
27.5
8.9
12
10
0.1
          Per gram of dry solids cake.
*JTU is Jackson Turbidity Units
                                  74

-------
Coliform determinations on wet cake samples averaged 22 MPN/g of wet
solids  (65 MPN/g  of dried solids) with a range of 3 to 120 MPN/g of
wet solids.  These results indicated good control of coliform population
in the filter cake.  No total bacteria or virus analyses were performed.
Disinfection was achieved by adding 500 to 700 mg/1 available chlorine
during standard processing.  Residual chlorine content of the process
effluent was 0.3 to 1.2 mg/1.  Samples of wet filter cake aged in
sealed containers for 10 to 30 days at 22 C produced no detectable
sulfides and were not malodorous.  Other cake samples dried at room
temperature for 3 days had no measurable coliform.

Laboratory analyses of filter cake solids produced during preliminary
field testing gave the following average results on a dry solids basis:
51 mg/g BOD5, 70 MPN/g  ooliform, and 1.3 mg/g zinc.  These data were presented
to the Nevada State Divisions of Health and Environmental Protection as
well as the inspector's office of Clark County.  Permission was obtained
from these parties to dispose of the filter cake solids as sanitary
landfill.   No special permits were required.  Filter cake solids were
accumulated in a plastic bag during plant operation and then discarded
in a solid waste hopper used by the marina.  Twice weekly these hoppers
were emptied in an authorized landfill area outside of Las Vegas.
CHEMICAL AND POWER CONSUMPTION

Average consumption rates of process chemicals and electrical power
are given in Table 21.  A recording kilowatt-hour (kwh) meter measured
the power requirements of the demonstrated treatment unit excluding
auxiliary postchlorination and zinc-removal equipment.  Total power
requirements for motors associated with auxiliary treatment was esti-
mated at less than 0.3 kwh.  Dry chemical (filter aid and diatomaceous
earth) feed rate remained basically constant over the entire test
period, even though influent waste characteristics varied substantially.*
Power consumption varied slightly as a function of process rate and
influent waste concentration.  Heavier wastes required longer processing
times by  rotary  vacuum filtration equipment.  Based on an average power
consumption of 5.4 kwh per hour of operation, a total of 22 kwh was
required to process 1000 1 (264 gal) of watercraft wastewater at a rate
of 4.1 1/min (1.1 gal/min).
*Dry chemical feed requirements are proportional to influent waste con-
 centration.  On automatic operation, dry chemical feed rate is set for
 the highest expected waste concentration.  This condition results in
 excess chemical consumption and overtreatment of less concentrated
 influent wastewaters.
                                  75

-------
EH
CO
O
O
§
H
EH
ft
S
D
co

§
U
o

Q
u
H
ffi
O
CM

0)
^
m
0

Cn
C
•H
4J
rd
SH
ft
0

rd
4-1 0)
•H O
C -H
3 M
ft




01
rd
On

q
o
•H
4-1
ft
0)
C
O





































rH
rd
en
S





rH




XI
rH
•o




H
rd

S
\
(")
rH




rH
x^
Cn
A;




0)
rH
rd
o
•H
g
0)
g

01
01
0)
o
o
SH
ft





4J
C
01

.p
rd
0)
SH



i£> CO ro rji in H
^D en CN 00 H rj>
•3* rH o <* ro ^
rH




ro CN vfl en ro ro
CN in O CN CO CJ1
rH O O rH O rO

in in
VD en r^ CN o
o r- CN oo ro
in H





CN o ro ro CN o
cyi m co en ^j* v£i
CN in CN CN
rH







rH O O rH Cn rH
rH ro rH r- CN in
rH


H rd
XI 04->
CD in o
•U EH
•H 0) —
SH 4-1 Q
O O) 0) -H $6
rH 4-1 4J rH
x; rd rd CD SH
O 4H MH O rd
0 rH rH —- XI
ft 3 3 U
>x co in T) 3
ffi -H -H Z

§3
C g SH C
•H -rH 3 01 O
U g -H H-) X!

rd rH O H rd
CJ < CO fe U




T)
^
rd
T)
C
rd
4-1
CO

^f in en
CN CN •*
o un m





v£i cn m
O CO ^f
O rH rH

rH
O rd
0
•
in
ro
rH
rd
CP

ro \.
rH
rd
Cn

in
rH


rH
^ ,*^
O rH

in
rH
rH
rd
4-1
0 O
0) EH
4-1
•H
0) ^1
T3 O
•H rH
x x;
o o
SH O
T3 ft

a: ca

g g
3 3
•rH .rH
T3 T3
O 0
co co
c
o
H
4-1
-P rd
0) C
0 -H
O-i V-i
o
rH
^
u

t —
•*
o





CN
H
O


0
rJ





r^
vo









00
o









0)
73
•H
X
o

rrj
*>1
K



•rH
rrj
O
CO
rH
rd
£>
o
g
(D
oi

o
c
•H
IS]

l£
ID
CN





O

0
0)
•3

-o
0
CN
.
ro
rH
rd
Cn


cl
3


ro
00

rH
*\
x;
3

CN
CN










T3

O)
4J
rH
O


O

CN
01
0)
rd
x;
ft
1
ro
•— '

SH
41
3
O
ft
mber 3, 1973. Schnell
01
0
S

«.
4>
4-1
|^
0
ft
Ol
PH

01
C
•r)
4J
0)
\J
SH
1

rH
rd
O
•rH
g
CD
r*
U

ro
r—
cn
rH


ro
CN

SH
0)

g
CD
£>
O
z
MH
0
in
CD
u
•H
SH


0)
*>
•rH
4-1
0
CD

W
rd















































B
O
C
H

*.
>
O
u

Cn
q
•H
(~l
01
•rH
rH
•a
ft


«
c
0
-H
4J
U
0)
c
•H
in
•H
T3

^_l
0
I4H
C
O
•rH
4-J
rH
O
in

01
3
O
0)
3
O1
rrj
C
•rH

rrj
0)
01
P

CD
q
•H
SH
O
rH
x:
o
Q)
rH
•S
rH
•H
rd
^
rd

4-1
C
CD
(J

0)
ft
in
>£>
X)
O
MH
rH
C
o
13
4>
0)
D
0)
C
• H
SH
O
rH
x;
o
4)
rH
•S
rH
•H
rd

CtJ

rH

1

o
CO
rH
Cn
c
•H
£>
ro
x;

0)
4-1
•H
SH
O
rH
x;
C)
o
ft

X.



•H
•a
o
01

MH
o
c
o
•H
4-1
3
rH
o
O)

4-1
q
0)
u

Ol
ft

rH
O



















































c
o
"—
CD

._
1-
o
— _
-C
o
i/>
O
O.

1
at a process rate of
r>
Is
M
^
•
in
M-l
0

4)
Cn
rd
SH
01
rd

q
rd

O

rrj
4)
in
rd
XI

4-1
C
0)
B
rd
0)
SH
4-1

T3
in
fd
T3
C
rd
4-1
0)

£q
o
MH

0)
q
01
g
01

•H
3
rj •
41 .t

j-
SH ~~~
CD —
3 r-
O
ft *fr
TJ
December, 1973. Based
*
rd
•H
C
IH
0
MH
•H
rH
rd
U

K
0)
in
o

c
rd
CO

Ik
q
rd
ft
g
o
u

o
•H
SH
-P
o
41
rH
W


£J
rd

01
rd
U

u
•H
rH
•a
ft

XI

CD
J_)
rd
SH

4)
£>
•rH
•P
O
4)
MH
W
4)
XJ
O
O
o
^
1^1
rH
CD
4-1
rd
g
•H
X
0
SH
ft
ft
rd
MH
O

•a
q
rd
g
O)


>i
rH
x:
-P
q
o
g
rH
rd
4-1
0
4-1

rd

x:
4-1
•rH
3

C
O
•H
4-1
rd
SH
0)
ft
0

01
3
O
3
C
-H
4-1
C
0
U
C
0

                                                         76

-------
OPERATING COSTS

Average costs of treatment chemicals and power requirements for the
demonstration system are given in Table 21.  Total cost for standard
treatment was $4.63/kl  ($17.57/1000 gal).  Postchlorination of effluent
at pH 7 with 2700 mg/1 available chlorine cost $1.45/kl ($5.49/1000 gal).
Zinc removal from the effluent at pH 9.5 cost $0.12/kl ($0.47/1000 gal).
Complete treatment consisting of all three operations cost $6.20/kl
($23.50/1000 gal).  Current prices for truckload quantities of treatment
chemicals were used in cost calculations.  Electrical power costs were
determined using current price quotations of 3.2C/kwh.  California
Public Gas and Electric Company quoted this price based on continuous
plant operation in San Jose, California with a monthly total power
demand of approximately 4000 kwh.
MAINTENANCE

Daily routine maintenance service involved resupply of process chemicals
and disposal of solid filter cake.  Lubrication of pumps and bearings
was done monthly.  All mechanical and electrical components functioned
properly and no equipment failures occurred during the 8-week test
period.  Under the field test operating conditions, one man managed the
plant and supplied treatment chemicals.
OPERATING PROBLEMS

No major operating problems were experienced.  Fluctuation in voltage
of supplied power caused periodic trip-out of equipment which was later
remedied with electrical modifications.  Consistent operation occurred
after long periods of down time with no plugging of equipment.  Level
sensors controlling the operation of the rotary vacuum filter equip-
ment required periodic cleansing of accumulated solids.  This was done
automatically with a small wash line from the effluent discharge pump.
Channeling of dry chemical in the feed hopper resulted in a decreased
feed rate to the surge tank.  This problem was significantly reduced
by installing cross baffles in the hopper.  Process control of pH was
constant with varying influent waste concentrations.  Only when cleaning
chemicals in the waste seriously changed the normal influent pH was it
necessary to adjust the process chemical feed rate for pH control.

Auxiliary equipment for zinc removal and postchlorination functioned
properly.  The retention coil and pressure filter did not leak at a
maximum test loading of 586 dynes/m2 (120 psi).  A single bag filter
was used during testing without plugging, and a constant process rate
of 3.8 1/min was maintained.  An antisiphon device and check valve were
required on the hypochlorite feed pump.
                                  77

-------
                              SECTION XII

                               DISCUSSION
The reliability and accuracy of BODs data obtained during field testing
requires discussion.  The BOD  test is an empirical bio-assay-type
procedure, consequently, the results obtained are influenced greatly by
the presence of toxic substances or use of a poor seeding material.
For industrial wastes containing toxic chemicals, the standard 5-day
incubation period is often insufficient for proper stabilization^0.
Toxic substances cause a decrease in microbial assimilation and oxi-
dation of organic matter present in the waste which results in less
depletion of dissolved oxygen.  Since the BOD  test measures the dis-
solved oxygen consumed by microbial activity, the empirical result is
low compared to the true value.  Evidence of this effect has been shown
in this work and is reported in the literature1^' 20/ 21.  After a
variable time lag, microorganisms become acclimated to these toxic
substances.  A stabilized waste results, which approaches normal micro-
bial activity and yields a more accurate BOD result.   Considering these
facts, the BOD testing of such waste should involve the determination
of the complete oxidation curve and the ultimate or total carbonaceous
BOD.

Since this approach was outside the scope of contract finances, 5-day
BOD determinations were made on very dilute samples of influent waste
and filter cake solids  (to reduce toxic material concentrations).
Those dilutions showing a minimum residual DO of 1 mg/1 and depletions
of at least 2 mg/1 were averaged and reported.  There is no acceptable
method for determining the accuracy of the BOD test,  but the procedure
followed in this work should have given BODs results with a mean
standard deviation of 17 to 20 percent.  Additional information relat-
ing to the oxygen-demanding characteristics of wastes involved in
this program are given by TOC, SOC, and COD results where determinations
are .not affected by the presence of toxic materials.

Process results indicated a net increase in total dissolved solids (TDS)
concentration after treatment by the demonstration system.  This is ex-
plained by addition of treatment chemicals.  Calculating the TDS as the
difference between TS and SS, influent wastes averaged 1610 mg/1 TDS.
                                   78

-------
With standard treatment, the process effluent averaged 4945 mg/1 TDS
for a net .increase of 3335 mg/1 TDS.  Based on average chemical con-
sumption, the addition of aluminum sulfate, sodium bisulfate, and
calcium hypochlorite totaled 1500 mg/1, which accounts for the TDS
increase.  Similarly, chemicals added during zinc removal and post-
chlorination contributed even more TDS.  After auxiliary treatment,
the effluent TDS averaged 11,100 mg/1 for a net increase of 9490/mg/l.
Besides normal treatment chemicals, sodium hydroxide and sodiuei
hypochlorite additions totaled 7520 mg/1 which accounts for this in-
crease in TDS.  It should be recognized that the TDS loading in the
effluent is exceptionally high.  Further studies are required to
optimize process chemical treatment to reduce the effluent TDS con-
centration.

Postchlorination of process effluent increased the removal efficiency
of nitrogen from 30 to 66 percent.  Treatment involved an available
chlorine concentration of 2700 mg/1 with 90 minutes retention at pH 9.5.
These nitrogen removal results are in basic agreement with preliminary
results obtained in the laboratory (see Section IX).  In recent work
on ammonia-nitrogen (NH3-N) removal for wastewaters22t the Ep^ reports
a requirement of 10 mg free chlorine to remove 1 mg of ammonia-nitrogen
by break-point chlorination.  During these studies on secondary effluents,
little or no chlorine demand was determined for other wastewater con-
stituents.  This case does not exist in the postchlorination of water-
craft waste effluent following physical-chemical treatment.  Soluble
organic chemicals like formaldehyde and methanol, not readily removed
during standard treatment, remain in the effluent to exert a chlorine
demand.   The application of 2700 mg/1 free chlorine to effluent having
approximately 250 mg/1 ammonia-nitrogen was insufficient to achieve
complete removal of ammonia-nitrogen.  The presence of other compounds
having real chlorine demands may explain these results*.  Without
further work, no statements can be made regarding the limit of nitrogen
removal that can be achieved by postchlorination at higher free chlorine
concentrations and longer retention times.   This approach of break-
point chlorination for nitrogen removal is quite expensive and in-
efficient.  Other possible methods for approaching the objective of
90 percent total nitrogen removal include air stripping of effluent at
pH 10.5  , ion exchange with clinoptilolite   (a natural mineral ore
with ion exchange properties),  a biological nitrification-denitrifi-
cation  .  Major work remains to be done in this field before a high
degree of nitrogen removal can be achieved efficiently and economically.
*No residual chlorine data was obtained on chlorinated effluent samples
but a strong chlorine odor was detected.

                                   79

-------
The high operating cost of the demonstrated system requires qualification
and discussion.  Disposition of concentrated chemically polluted waste-
waters will utimately be decided by the availability of adequate treat-
ment facilities and not the cost of operation.   Since public recreational
activities are concentrated in rural land and marine areas, access to
municipal treatment plants may be impossible or prohibitively expensive.
Truck transportation of wastes is becoming increasingly expensive, with
rates as high as $40/1000 1 ($150/1000 gal) reported in Washington and
Northern California's.  in many sanitary districts, chemical wastes will
not be received for treatment because of the serious upset and loss of
operating efficiency caused to biological treatment plants.  A great
number of municipal sanitary treatment plants are presently overloaded,
and they do not have additional flow capacity to treat recreational watercraft
wastes which require 10 to 220 times dilution before toxic effects are
eliminated.

Results of field testing at Lake Mead have shown the demonstration
system to provide greater than 90 percent removal of SS, COD, and BODs
from recreational sanitary wastes containing chemical toilet additives.
These results, combined with variable capacity design and automatic
on-demand operation, indicate that the demonstration system offers an
effective method for the treatment of low volume flows of concentrated
chemical wastes where conventional biological treatment would be in-
adequate and troublesome.
                                  80

-------
                              SECTION XIII

                               REFERENCES
 1.  Pretreatment of Discharge to Publicly Owned Treatment Works, U.S.
     Environmental Protection Agency. Washington, D.C. Office of Water
     Programs Operations, 1973. P 1-15.

 2.  Federal Register, Washington, D.C., 3_7_  (122) : 12391-12393, June 23,
     1972.

 3.  Federal Register, Washington, D.C. , .39  (42): 8038-8044, March 1,
     1974.

 4.  Personal Communication.  Contra Costa County Sanitary District,
     Antioch, California, February, 1973.

 5.  Methods for Chemical Analysis of Water and Wastes, U.S. Environmental
     Protection Agency, Water Quality Office, Cincinnati, Ohio, 1971.
     310 p.

 6.  Personal Communication, Holiday Harbor Marina, O"Brien, California,
     May 1973.

 7.  Earth, E.B.,  et al, Summary Report on the Effects of Heavy Metals
     on the Biological Treatment Process.  Journal WPCF, 37  (1) :86-96,
     1965.

 8.  McDermott, G.N.,  et al, Zinc in Relation of Activated Sludge and
     Anaerobic Digestion.  In:  Proc. 17th. Industrial Waste Conference,
     Purdue University, Lafayette, Ind., 1962. P 461-475.

 9.  Interaction of Heavy Metals and Biological Sewage Treatment Proces-
     ses.  U. S. Public Health Service, Cincinnati, Ohio. 999-WP-22. U.S.
     Department of Health, Education, and Welfare. May 1965. p 61-78.

10.  Gellman, I.,  and H. Heukelekian, Biological Oxidation of Formaldehyde.
     Sewage and Ind. Wastes. 22:1321, 1950.
                                   81

-------
11.  Noller, Carl R. Textbook of Organic Chemistry.  2nd Edition.
     Philadelphia, W.B. Sounders Company, 1958. p 655

12.  McKinney, Ross, E. Microbiology for Sanitary Engineers. New York,
     McGraw-Hill Book Company, Inc., 1962.  p 194-198.

13.  Lampe, Wallace D. The Rate of Endogenous Respiration in a Completely
     Mixed Activated Sludge System. M.S. Thesis, University of  Iowa,
     Iowa City, Iowa. 1966.

14.  Gilcreas, F.  W. Inhibition of Sludge Digestion by Penicillin
     Manufacturing Wastes. Sewage Works Eng. 3/7j360, 1946.

15.  Heukelekian,  H. and M.C. Rand, Biochemical Oxygen Demand of Pure
     Organic Compounds.  Sewage and Ind. Westes 2T_(B) , 1955.

16.  Stafford, W.  and H.J. Northrup, The BOD of Textile Chemicals.  In:
     Proc. Amer. Assoc. Text.  Chem. and Colorests. 1955.

17.  Benneworth, N.E. and N.G. Morris, Removal of Ammonia by Air
     Stripping, J. Water Pol. Control. 71(5):485-492, 1972.

18.  Boos, R.N. Anal Chem. ^D:964, 1948.

19.  Brown, P. and P.R. Andrew, Some Effects of Zinc on the Performance
     of Laboratory-Scale Activated Sludge Units.  Jour. Water Pol.
     Control. 21(5):549-555, 1972.

20.  Standard Methods for the Examination of Water and Wastewater.  13th
     Edition. New York, New York, Amer. Public Health Assoc., Amer.
     Water Works Assoc., Water Pol. Control Fed. 1971. p 489-495.

21.  Rudolfs, W.,  et al. Review of the Literature on Toxic Materials
     Affecting Sewage Treatment Processes, Streams, and BOD Deter-
     minations. Sewage and Ind. Wastes. 2_2_:1157, 1950.

22.  Cowan, J. U.S. Environmental Protection Agency, Cincinneiti, Ohio.
     Unpublished report.

23.  Slechta, A.F., and G.L. Gulp, Water Reclamation Studies at the
     South Tahoe Public Utility District.  J. Water Pol. Control Fed.
     39^(5) : 787-814, May 1967.

24.  Downing, A.L., et al. Nitrification in the Activated Sludge Process.
     J. Inst. Sewage Purif.  (Brit.), 130, 1964.

25.  Personal Communication, Lake Shasta National Recreational  Area,
     Redding, California. May 1973.


                                  82

-------
                              SECTION XIV

                              APPENDICES

                                                                   Page

A      Analysis of Recreational Watercraft Waste Samples            84

B      Waste Characterization Data of Atomic Absorption
       Analysis for Twenty-Two Elements                             94

C      Statistical Results of Waste Characterization Data          100

D      Activated Sludge Material Balance Equations                 106

E      Results of Lake Mead Testing                                109
                                   83

-------
 X
•H
t!
 C
 0)
 a















^



•*



eo


















1
*
Jl
a.
CO




1

CO
1



rH
1

CO
CM
CO

rH
7
CO

rH
CM
1
CO


1
r*,
CM
CM
CO


rH


CM
1
CM
CO

rH



CM
CO



S
^

o
CJ


a)
3
•0

•rl
•o
P


S
•H


°
rH
M
5
2
•3
3
•a
iH
•H
'S
M
rH

•H
"S




•o

T3
M



O
a
i



a.
H
41
1




CO

CM
CM
CO


CO

I
CM
CM
CO

R
CM
CM
CO


R
1
CM
CM
CO


R
1
CM
CO



eo

i
rH
CO





O
1


n









u
*
S
iH
H






rH
«




rH
«


4J
H
5


4J
rH
CO



rH
£





U
rH
CO




to




a
ft
rl
5
7


CM



M
*


4J
•H

O
I
o

•*
Power
CO
eo

0,
00

rT
01
g
PH

VD
en


4)
£
tu
4J
•H
CO
O
a
g


4-1
9
*
&
H
u
(0
1
U
«
3
O*

m
i
H
§
CJ
(0
g.

m
H

1



m
H



m
H
i




m*
H
01
4J
•rl
to


g


0)
5
4-1
-H
1
rH
U
•H
§
6






O
in




i
i
i


o
m
00



M




tN






m



m
CM
en


p
i
o
0
U
a
CD
3






1
-1




T3
(*

.*
m
CM


1
T3
m


1

m





4>
rH


ta

rt
t)




00
at
4J
0]






•n
S





£



1

B
1
s






o





°



3


O
CM



O
CO





0
"*





1-1



1

^
!






CO
rH





*
•a
S
o
s
•o
tu
1



1-1



**






e*
4





£



t


1
N






§
rH
rH




§
CO
en


S
m
rH


o
§
CO


§
•
rH





§
•*



o

""".


1
•H
•rt
*
•0
g
O







vO




CO
^


CM
r*.


00
oo



CM
00





m
m





r-.






a




o

K
CM
rH


"A

X
N

•a
X
CM


a
X
vO


0
X

"





?
rH

•ft


X
o

rH
E
I
z
I
a
o
IM
•H
rH
S
                                                 84

-------
w
fa

§
H
w
OS
o
0)

                                            85

-------
w
w
i-q



O
H



H

U
w
H

 X
•H
 0)
                                                     86

-------
 X
•H

Ti




 I
 ft
                         i
                         o
    s
    o
                                                                                                              3
                                          I
                                                                                §
    g
    O
S

 X
                                                               §
S
CO
o
1-4

M


S
                                                   I
                                                   s
                                                                                                                       e

                                                                                                                       §

                                                      87

-------
CO




w









u


H





A



O
\-\




1



1






 H
 W



 §






 •=c

 X
 •H
m
cn

CO

en
en

CM
en

o
en

^
o

rfl
OS
CM



£
CD
CL
CO
rH
OS
m
1
CM
cn
rH
1
O
vO
1
CM
OO
CO
rH
1
CO
I
CO
rH
1
1
CN
cn
rH
1
vO
m
i
CM
CO
rH
1
u-i
1
CM
CO
rH
1
Kl-
in
CM
CO

$
CD
0)
4J
•H
CO
O
t
U
ndividual
M
cfl
•iH
•H
M
idividual
M
rH
§
13
•H
•H
"3
M
idividual
M
rH
cO
3
"3
M

CU
CL
H
CU
CL
cn
r-,
i
rH
**
en
r-.
i
rH

1
rH

CO
1
rH
*
en
[*-
i-H
"
en
1
rH
•*
CO
r-.
rH
•*
OJ
AJ
Q
s
Collectic
«
*"
«
1

4-t
•H
CO
O
1
O
en
CU
ca

3
CU
CO
3
X
CM
CU
?
M
cn
0)
to
3
X
^f
CO
0)
CO
*
CO
aT
g

tt
c
n

&
ca
o
P3
u
-•H
o bi
H eu
m
i

u
•H
Ot
in
H
1
U
1
4J
CO
ii
g
1
4J
cO
X
1
1
4-1
cO
W
CD
••H
4J
•d
rH
to
u
-H
U
1
1
1
m


rH

CM

"

•"^


l—t
in
i
o

CU
CM
CO
•Si
§
CM


00
(U
ca
cO















CO
•H
CO
r-t
C
a
o
CM
m
0
CM

o
vO
rH
1
CM
O
rH
rH
cn
0
m
l^*
0
en
'*"

00
E
CO
O
"*
§
VO

o
rH
rH
0
rH
O
m
CM
0
o
VO

-------
o
,-1
U-l
O
VO
0)
60
nj
Pj






en
w
ij
d<
w

H
H
03
<
S
r .
t^
fa
8
H
H
<
[5
J
<
Z
0
EH
<
%
(j

H
&
i-M
O
w
H
W
>l
J
<
g

en







OO
en







P^
en








vO
CO



1
^
ex
I


rH
1

vO
1
CM
CD
CO



rH
vO
vO
1
CM
00
CO




"I*
m
vO
I
CM
CO
CO



1— J

vO
1
CM
00
CO





rH
1
CO
1
CM
CO





rH
1
CM
vO
1
CM
CO





rH
1
iH
vO
I
CM
00
en


Vt
s

o


fl
d
t)
•H
•H
•a
C
H


0)
3
T3
-H
M



CU
4-1
•H
CO
O
a

°


cO
-d
•H
•H
1




rH
rt
3
•d
•rH
•rH
"8
H




n)
3
•d
•rl

•H
-d
C




cd
3

1



CU
a.
H

H
0!
C
S


-s.

1




o
o
o
•
CN




§
PS.
m





o
o
0






§
CM








O
O
O
CO







o
o
CO






o
3
CM
rH
S
£
4J
•rl
&
•H
j_j
1 Conduct






en
01





vo
fs.






PS.






in








m
^









OS







r-l





X
O.


en
o
rH
X

vO



Os
O
*"^
st
CM




PS.
o
r-l
CO
CM



ps.
O
rH
CO
CM





PS.
O
i-H
*
CO
CM





VO
O
i-H


CM





(s.
O
rH
M
S
rH
a
o
i-H
1
g
1 Colifo;
89

-------
o
r-4
(M
O
r*.
CD
00
>
H
4)
i-H
CL,
I




en

i
CO



cn
i
CO
1





en
p*.
i
oo
1


R
GO
**






en
i
CO



R


-*





en
r-
i



0)
n)
O
C
•H
4J
CJ
0)
rH
pH


•o
4t



S


a
«
S
V
j:
CO



T3
«

H>
1

•3

•«
>->






1
4)
3



g
4J
1$
O
*J
CO





U
o
CO




o
•rH

to
U
o
,-J







CM












-




rH






rH






^






*



r4
0)
,0
2


i-t
1






CO
g



CO
41
V*






•g
01


^
4)
ft,






-C
CO
at
fu



CO
CD

fc





CO
01



(U
O-
H



4J
3:


0)
•H
CD
O

1

V
•H
1
O



41
4J
•H
n
o
o.
u

CM
CD
i
o





4>
Compos it


VO
cn
4)
CO


sc




to
cn
4)
CO
I

w
£
«
t-J
O)
s
H


1


41
•H
CO
0
D.
«

4)
•H
CO
O
CJ



4)
4J
•H
CO

o



m
H

•o
O
o

a)
s
M


ss
rH H

H o




C
a
li
U 4J
i-H -H
iH M
3 O

ct>
•H
4J
•o
CD
U
-H

O







O
rH



O
vO






O
00



o
CM






O
O
I-l



,


1






o
en


5
i— i
o

4)

CO
n)



CO

0)
a»
CM


CO
1






CO
S1
•o
CM


CO
•3
s
CM






13
CM



CO
•3
41
s

CM





CO
•o



CD
00

CD
4J
CO
m
















































•H
CO
m
c
rH
a









o
m




§
r-T






o
CM



O
0
CM






0



O
o

CM





S
rH


_
,— (
"f




W





O

m



o
§
*







0
cn
GO


o
-*
r-t






rH



S
cn

rH






O
cn
CO


_
ff




CO
to







rH



R
•






r*.
en
o



vO
o






vO
in
0




CO

0





p>.
CM
0



3




£






en
rH



0
cn







m
i-H
O



en
o






r-
CM
0



cn


0





m
rH
0



&?




CO







cn



o
CM
"







O


O
m
^






0
s



o


CM






S
r-



I1




O
g







O
cn
CO



0








-


o
rH
rH






0
ON



O
o
P«s

rH






O
rH



ff




S





o
vO
o
CM



O
"







O
m



O
00






§
oo



o
CM
CO

en






o
m
r-



bO
C



m
a
a




o
CM
P-.
cn



0
rH
*






§
rH
cn


o
rJ
CM






0
rH
m
m



o
vO
en

CO





o
cn
rH



f




o
CJ







rH



O
CM
*







O
CM
m


o
3
rH






0
CO
rH



o
en


CM






o
»n



bO
e




EH





O
CM
O
i-H



0
in







o
rH


o
rH
rH






§
cn



o
r*.
CM

CM






o
CM



1


2;
1
ff







O
00



0
vO







O
in
CM



9
•^
CM






O
en






vO






o
s



-»


^+
o
pi
I







i-H
rH



0
CM







CM
O
CM



^
•d"






O





o







CO
m



I



u
•iH





O
o
CO
vO



§
O







o
o
cn


o
vO
m"






0
s



o
o
o


rH





§
O

S
5
4J
^
i-t
4J


TJ
C
o
o







CO



CO








m
CO



cn
^'






CO




vO

0>






CM








a
0.



o
i-H


cn
CM


O
rH
en




r-
o
rH
X
CM
vO


o
rH
X
S






m
o
rH
X
s



CM
S

cn
CM





tn
o
x
CM
vO
rH
E

rH
&
1
E
o
14H
•H
rH
o
u

















C!
0
•H
4-1
3
CO
a.
^
£ d
S 5
a] 4J
H U
4J 3
O>
1!
A a
4-1 M
01 CD
m co

CM cd
u
* 4J
S j
4J 6
CO rH
g^
Q) 4J
U
cd 
-------
o
rH
(M
O
00

3?
0.





w
w
a
Oi
w
w
H
w
<
s
H
CM
U
A
H
H
fiC
S

ij
<;
2
o
H
EH
<
W
PS
O
§
PM
o

CO
H
w
>l
3
<


*
f$*
X
-H
T3
£

i
E?
at

a.
1




CO
i
CM
CM
"*


CO

t-H
CM
1




cn
r-»
i
i-H
CM
1
*d-






en
r-.
i
oo






en
r-.
1
00
i
••d"





cn
r-.
i
oo
i









en
OO
-d1



01
H)
Q
C
•i-t
4J
U
01

o
o

rH
4)

P-i

rt




j:
w
a)
r-(





J4
(0
g
&y






j-
CO

^
•<
rH
rt

•H

U





o
CO




o
CT*
rH






m
rH






o
o








o







o

r**








o
h*



d-
1
3
o

a>
4J
(fl
«
S



00
t-<
3
O
o
rH



"ai
g
rH



CO
»-l
3
O
^:
o
rH






4J
C
o
g
rH





^
4->
B






•U
|

CM






ta
fC
U
S
CM






<

*
rH
c

O.


w





0
oo
VO




o
o
vO
r-





o
vD
rH







0

r-l







3






g
"^
o
cn








o
rH



,_,
00
e




to




o
m
m
rH
rH



o
oo
o
vO





0
§









0
r..
vo







o
o






g
r-l

rH








O
S
oo



^
~»
g




£





OO
OO
en




5
i-4






o
VO








CJN
CM
o






rH
en







rH

m








CO
rH





ff-2




H





00
CO
CM




in
0






rH








vO
0






00
o







rH
CM

cn








en
1—1




^
6-5




B




0
CM
CM
O
rH



O
rH
VO
cn





o
rH









0
CM







O
O






g
**„
CM
rH








O
m
vo
CM



^^
00
E




0




0
s
m



o
r-l
CM





0
VO









CM







O
O






O
vO
CM

r-4








O
CM
rH



^
00
g




U




o
m
"!
rH



O
CM
-d-





o
h-









o
vO
vO







o
en






o
o
"*.
0









o
a
en



^^
00
E




8




0
r-.
r-
CM



O
rH
^






o
oo
vO







o

CM







O






g
r*.

m








s
en
CM



^
"M
G




Q
8




O
m
en
m



o
rH
rH





0
rH
a*









o
t-»
CO







o
vO






0
CO

r-l








O
m



^
00
e




i
H





O
OO




0
00
00
rH






O









CM







O






0


rH








O
m



^
bO
e




rf




O
vD
rH



0
O
rH






O
en









O
m
CM







m






o
S3


o
3
•o
C
o
u





0-N
m




CM
00






CO









m







o







vO

f^-








00
CO










a





o
CM
vD

r^-
0
rH
X
(M



C-J
O
rH
X

-------
0
r-l
H
3
2
<

<
X
-H
T)
C











cn







ON
m
rH




00
cn




CO
-d-
o*






vQ
O
CM




n
O





o
0

CM






6*2





00









O

m







CO
CO
o




S
CM




cn
en
o






r-l

r-H




r^
^
O




^
m

i— j






fr~£




C/j
>






o
o
CO

o
r-H






o
m
-d-"



o
m
r-l



O
m
r-*.






O
CJN
in*




o
o

CM




o
m
en





^

ao
E





g







O
cn


ON






O
in
cn



o
m
r— i



o
3
rH






O
O
cn
cn




o
m





o
CO
o

m





CJD
E





O
w






o
o
-d-









O
CO
00



o
o
cn
T-l



O
in
CM






O
r-H
^




0
CM
CO
r-H




O
ON

t--






6



m
Q
S






O
O
I—I

0
m





o
o
cn
CM
i-H



O
o
ON
CM
CM



O
in






o
o

CM
T-l




O
cn
m
cn



o
o

m






00
-S




a
o
u






o
en
CO








o
ON



o
3



O
cn
en
r-l






O
ON
CM





O
vD
CO




O
o







GO
&





t
H






O
in
m








o
ON
en



o
CO
CM




O
ON







O
CO





o
a\
r-H




O
r-H
O

cn






E



i
rn
S
^






o



r-l






C'
CO
-



C
O1
O1




o
ON






O
O
ON
rf





O





8






/-•

bf)
3








01
O
a)
4J



CD

2
QJ
4J
U




C
s.




in
aj
4-1
CJ
OJ
4J
'O
OJ
C
o








ON
CM





CM






O
ON
en



^^

00




o
C
•rH






o
o
cn

CO






o
o
CM
CM



O
O
cn
-d-
CM



0
S






O
o

CO




o
0

m



0
o
cn

CO


|

^
^

•rH
4J
0
a
•o
c
0









o

00







0




00




r-
cO







T-4
r-~





CM
in







o>












33





O


x

CM





O
T-l

cn
CM

ON
O
r-l
X
-d-
CM


"S
T— 1
X
cn





ON
o
rH
X

CM


O
T— 1
X
cn
CM


m
0
i-H
X

CM
VO
6
o
o

P-.

" —
1
o
U-l
•H

O

92

-------
-H
•o
                                            93

-------
co
H
co
H
EH
O
O
H
•s,

I
CO

a
D
CO
   co
2 EH
O 2
H pq
EH S
sC W
N (J
H W
05
W O
EH S
O P
O  EH
X  2
U  W
13
>=C  O
S  fa
m

x
-H
T3

QJ
a
a
            uinuTumiV
w
4-)
• H
c
              rH 60

              < E
                  OOOZOOOOOOOOOOOOZOrHOO





                  Q Q Q rH Q rH Q Q Q O Q Q Q Q Q Q Q Q Q Q Q

                  Z z' Z O Z o Z Z z' Z* Z* Z* Z* Z* Z* z' Z* z' Z* z' Z*







                  ZZZOZZZooooooozZZoooo




                  OOOOOOOOOOOOOOQOOOOOO













                                                                         (H
                  QQQQQQQQPQQQQQQQOQQQQ'

                  z* z' z z z z z* z' z* z* z z' z' z z' z z z* z z* z


                                                                         r-t


                  PQQQQQQQQQOQQQQQQQQ    Q

                  zzz'zzzzz'z'z'zzz'-zzzzzz^z


                                                                         IM


                     Q O Q Q Q Q Q O Q Q Q Q Q Q Q Q Q Q P Q    w  

                                 I  I   t  I   I  I   I  I   1  I  t   t  t   I  I   1  I   I  I   I  I



                                 I  t   I  I   I  t   I  I   I  I  I   I  I   I  I   I  1   I  I   I  I


                                000000000000000000000000000000000000000000
                                                                         • H

                                                                         00  II
                                                                         ^  z
                                                94

-------
co
H
co
§
H
EH
o
co
u
H
s
o
o

CO
EH
J
D
co
Q (0
    CO
h^  C_l
§  2
H  W

<  §
N  rl

aw

E^i
U  P
<  EH

O  H

H  EH
H

w  O
m
 x
•rH
 C
 0)
                     umipog
                     J9AITS
•P
•H
                    ISO

                    6
                            - CM  rH
                                               • ^- to OO  •    ^-^-
                                             2    10 00 2    LOO
                                                                                             Q^- Oo Is-
                                                                                              • vo   «O* rH
                                                                                             2 0-) 2    to
                                           Q             Q                                 Q
                                            • VO rH (VI t"-   •rHOt^OLOOOOOlOrt'  • OO O O O
                          000000202000000000000





                          Q Q Q Q' Q Q O Q Q Q Q' O Q Q Q Q Q* Q Q' Q Q


                          2' 2 2 2* 2 22 22*222222*2'22'2*2'2*






                          OO ^^ tO CTl \O G5 ^^ i^J ^^ O"l OO ^H i™H O"! '"dj* GO r^ O^ O^ ^^ ^^
                          tO ^D LO        nH C^J tO OO C*J OO pH O"l ^J ^Tl nH    OO fO O*J tO
                                                      rH      [^ ^^ j^^ ^^ r^ ^^« ^f) fv, j^^


                          2o2rH2"o222202oo2'o2csooc5





                          Q Q* Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q


                          2 2' 2* 2* 2* 2' 2' 2' 2* 2* 2 2* 2* 2' 2' 2* 2* 2* 2* 2' 2'


                                                                                                 SC


                          QQQQQQQQQQQQQQQQQQQQQ


                          2' 2* 2* 2* 2 2' 2 2 2 2* 2* 2* 2* 2* 2 2* 2* 2* 2' 2 2      E

                                                                                                 o




                          00000020tOrH22rHfvl2fM0020rH     'e   ^
                                                                                                 3
                                                   <    <
                                           I   I   I   I   I   I   I   I   I   I   I   I   I
                                                                                          I   I   I   I   I    I
                                           i   i   i   i   i   i   i    i   i   i   i   i   i   i    i   i   i   i   i   i    i
                                         cgrgtvicscvir^r^cvjfMr>j(N)cMtvitM(vitN](sjrM(vjtN  CM
                                         COOOCOOOCOOOCOOOOOOOOOCOOOOOOOOOOOOOOOOO  OO
                                                                                                 c   a>
                                                                                                •H   -3

                                                                                                 c      o
i/)
o
                                                                                                r-l   O
                                                                                                <  z
                                                                95

-------
 w
 H
 !S
 o
 H
 o

 CQ


 U
 H
 a
 tf
 o
Qn3
   CO
H H
EH S
<, H
IS] ,4
H H

W O
EH ft
U P
u
w a;






              Q Q Q Q Q Q Q O Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q


              zzzzz'zzzzzz'zzz'zzzzzzzzz

                                                                                 n!


              QQPQQQQQQQQQQQQQQQQQQQQ



                                                                                 S


                                                                                 O

OTU8S.IV   QQQQOQQQQQOQQQQQQQQQQQO     „,

              Z Z* Z* z' z' Z Z* z' z' z' z' Z* Z* Z Z* Z Z z' Z Z* Z* Z* Z     -H   o
                                                                                 C'   ^)
                                                                                 3   *J


                                                                                 •H

                                                                                 C   C
                                                                    CM           >   Z


                                                                                 DO  II

                    <
              r-Hi-lrHiHrHt-lrH'-IMt-lrHi-l
               I  I   I  I   I   I  I   I   I   I  I   I   I  I  I   I   I  I  I   I   I  I   I      „,   _,
                              i   i  i  i   i   i  i   i   i  i   i   i   i  i   i   i  i   i   i   i  i   i   i
                             cMrsipgfMrviNCsir-a(Nicsjpvjf\]r
-------
 co
 H
 CO
 EX
 t4

 £
 §
 S
 o
 1
 U
 fa
 o

 CO
 D
 CO
 Qrd

 Z8
 o  is
 H  W

 <  w
 IS!  i-3
 H  W
 04
 w  o
 EH  S
 U  S

                                  CMUO
   UIHTP°S   OrHtOOOtOi-lTl-t-.tOOOOOOr')CT>LnoOi-(t-*a-LO

                r-Hcnoir-cnoaivOr-icnoi-tcMi-i
                                rH












                Q    Q  Q O O Q Q O Q O O Q Q Q Q O Q Q Q Q Q Q
                  • oo	

                2r-i222222222222222222222








                Locr>oooooooo\or^-t-~r>-TtrOTti-ioo»o«*<(j-t^fMiHCM
                             rH    i-H                t-H





                OOCSlOOOi-lr-HiHrHrHr-trsJOi-IOOOi-IOOOO


                                                                                           I


                Q O Q  Q Q Q Q O Q Q Q Q Q Q Q Q Q Q Q Q O Q Q     £


                2 2' 2*  2* 2 2* 2* 2 2 2 2 2' 2 2 2' 2 2* 2 2* 2* 2* 2 2*     &

                                                                                           g
                                                                                           ca


                QQQQQQQQQQQQOQQQQQQQQQQ     .H


                2* 2* 2  2* 2* 2* 2* 2* 2* 2 2* 2 & 2 2* 2 2 2 2* 2* 2* 2' 2

                                                                                           E

                                                                                           i
                \OQCMQQQQLOr-OQf~OOirtvOQaQQQrOQfM     O


                O 2 <*i 2 2 2 2 O-i 2 2--I O o O 2 2 2 2 2 O 2 O     %   ^
                                                                                           H   O

                                                                                           §   S


                                            Q             Q    O       Q    Q        5   "°
                MOOOOOvOOOO  «O\OiHCNl  -^t   -bOO  »O  «^-          j>

                                                           - ...       ... _        C   C
                                               Lft                      (s                 (u   _o

                                                                                           • H
                                                                                           t«  II

                                                                                           in    .
                                                                                           •1-1   a
*                               ***s ^^  -   '   •   '   •   •  ....  _-   -   ....      ^   ^r



                 I   I   I   I   I   I   I   I   I   I   I   I   I  I  I   I   I   I   I   I   I   I   I      rH
                                                                                                V
  bo            oooooooocooooooooooooooooocooooocoooooooooooeo


                                                                                           rt
                                                              97

-------



H

§
o
H
a
0
CQ
U
H
fc
SULTS C
8
1
Qd
2 g
O 2
H H
EH S
< H
N ij
H W

EH 5
U H

ffi 2
U W
H
<; o
5 [i)
CQ
•H
C
0)
*

pB9T

uoai

Jaddo3


HBqo3

uinxuiojqo

-TSK)
uiniuipBD


uininXjiag


UltlT-IBg


oTuasjy

uinuiuinxv
(/)
•H
G
rH
rH "^
rH 00
< 6


22222o\ocM2 i — i tocsi2OCDOoooo o
O rH
rH t-~ rH tO i>] ts] rH
• rH
rsj rH

C3 t^-r-l f^*1 fT*l fT*) f^ f^*t ^*\ ^^] £^ ^j ^j p^) j**^] £13 f|^ C^l f^*j CNJ ^^ dj
22222222222222220202
• * | i |
f*^, (— \ (*^ f^) cs] |_^ t^j «^ \^ c^ ^^ tO vO I**~ ^«C^ ^O t*H T~H C^Q ^H t~H
00220^-0^0^0^ .-^CMOOOO 0
rsjOOOOOOOOOOOOOOOOOOO rH
rH CM rH
.LnOOLOLOOOOltOOOOOCTl.... •• rH
20oooo^oooc,02222rHrH22

p p p P p P p p P p P p P p P P p P P p o
22222222222222222222

PPPPPP PP PPPPPPPPP rH
222222 22 222222222 o

pppppppppppppp PPPPPP
22222222222222222222
. . . . o
P P P P
22 t^ rH CM un rH 2 2 
CO
1/1
+J
1— 1
3
r-H
r-<
<:
rt






















•o
o
«)
0)
•a

+-"
o

-------
w
H
EH



O
u
H
•s,
O
CM
O
Dn!
H W
EH S
< H
N J
H H

H O
EH S
U EH
K a
u w

H EH
EH

<3 O
S fa
ffl

X
•H
T3

 ot~-oocr>ocvjtorj-Lo^ot--oocr>OrHborj-Ln>o
                               \Dvo\ovovot--t^-t--r-st~~t^r~-r-t~~oooooooooooo
                                i  i   i   i   i  i  i  i   i   i  i  i  i   i   i  i   i   i   i   i
                               O-lCMCMCSI(N]CMts](NI
                                                                                                           -3
                                                                                                            O
                                                                                                           U
                                                                                                           0)
                                                                                                           O
                                                                                                           -o
                                                                                                           O
                                                                                                           z
                                                                                                           
-------
I

§
H
g
N
H
o
I
s
O
H
EH
W
H
E-t
 o
•rH
•O
 C
 (1)
 ft
      £•


      3
4J  B^w
O "U 4J
co S "a
m Q
ON O

U
•tf d
fc« O
3 s
5 *>
t/l CU


U,~N
*S w6
fill
*3 iJ

 (S








is
1.3
I5







Minimum
Value



h K
V V
a «
81
s 2
S<2



§o
CD
rH fN.
CO





§
m




O
5









s
00








00

ON
00








s
o








CM



/-*
rH




S3
	 ,

o o
33
CN





O
-*




O
CM
rH








0
rH
en








^

CO









0
ON








en
NO



^
rH




W
(A


O V0
CO CO
CM O





vO
en
o





00
t-H








f^
oo









CM
^









en
00








d





^^^
H


CO
H


00 CM
0 O





*1
o"





o
vO
O*








^
CO










rH









ON
rH








8
d




-
^
H


E


is
rH CM





o
ON
en




O
O
00
rH








O
NO









0
rH
IN.









O
o
rH








O
ON
m



if^
r-t




g


0 0
00 r-N
rH





o
CM




O
CM
~*








S
in
A








0
IS.
**l









O
o









O



^
rH




£


S S
NO CM
CM rH





o
en




O
o
O\
•-1








o
^








o
o
CM









O
CM








O



,—•
rH

lr


f


O 0
i-< CM
r~ m





S
ON




O
(M
m








o
00
r-l








0
CM









O
CM









O



/"X
rH




§


00
CM





O
00
en




o
CN.
•N
«H








O
OO








r-(

05









°
OO








ON



j^>
rH

B


I
H
	

oo
ON CM






O
r-l





O
en









0
O








CM

ON









O









00



^^
rH
M
8

x
f
	

§s
en rH






O
fN.





0
CM









O








*>

1-4









§









3



/-N
r-<
00
f

Nt
S
1
H


«
CM o






00
00





o
m
r-l









S








o
en
CO









o









o
o"



^
rH

B


M


§O
^3
*/«T
CM



O
§
Nt




8

r-<







O
O
O
00








g

ON









CM
O








§
CM
r-t

|
•*-*


i?
•rl
•H
U
|



O CM
OO fN.





M.
o





VO
(N,









r-










m










QO
OO







en
m









0.


o
K O
m
"*


o
t-H
>t
m
— '



o
X
0

*"*





o

X
•






'30
0
rH

K

vO






°0
rH
X
CM







m

rH
B
O
O
^
g
a
•^

0
U4
•H
rH
S





9
•H
rH

§
Q
CO
"4-1
0

•rl •
U Q
3
*J rH
>
£ O
ni -3
« b
C« U
JG
01 i->

SB a>
0 3
S rl r-l
*W (d
0 « >

cn § t» S
rH \4 U
. n) y
u m  O
CM M W rl
C •O 0)
1 -rl O<
4J 4) 1
rH x .c m
crj bO •<-> ON
O  O -H
ii 
w a) i 5p
(Q CU rl
0) > B
rH 1 8>
g. g W 3
S 4 O rH
S « o m
w £ od >
Cfl ^i U "^










                                                            100

-------
I
g
H
U
g
 U
 C
 IP
 ft

e 85
 oS
fa
a «


I *

J4.3
e a
S"


U M
a a
a o!
2 §
n rt
rt p^



O 0
$5
•4 i-*





O
CO


0
8




0

OO
CO



CO
CO

m

0
CO
in





CO



^
r-f
fiP
B


CO
w


0 O
co *n
r- O
CO ft





o

vC

o
CO




o

1— 1
CO


Q
M?

CO

0
CO





o



/_1_
i-H
M)
B


«


in i-i
~H 0







o

8






m



CO
vD


o
•




CM






,__
6-S


CO
H


CO CO
ON co
0 0





T-*

O

CO






0



ON
CO


*






•





/-x
fr*


en
&


0 0
O1* CO
CO i-<





o

m

o
i-H




o

ON
CO



«

CM

O
m
CO




o
•*



j—s
i-t
"&P
0


8


ss
CO ON
CM





0
m
CO

o




o

m
CM



o
CM
CO


O
CO
"•




o
r— 1



^^
l-l
op
S


§


0 O
CO "1
•4" *~|





0
CM
CO

o
ON
CM




O

QO


O
i-l
OO

CO

§
CO
ON




O
ON



^_^
r-H
00
8


B"


O 0
O M?
CO CM
O **
i-l


0

m

i-H

o
CO
CM



0
CO

o
l-l


o
ON
p*.

00

O
O
o


o
I— 1






l-l
60
S


§


O 0
l-l l-l
•* CM
CM i-«





O

CO

O
00




o

CM



O
CM
CO


O
CO
CO





o




^^
l-l
M)
B


A


O O
ON ON
m r-.
^4







CM

O
ON




O

^



m

"

o
00





in
o




i-H
bO
W


ff


O O
00 CO






o



o
00






o
CM
CO



00
0
ON
"

o
CO
•>





CM



^^
rH
bO
E


S
H


i-H ON
m co
CM







CO









v§



CM
ON
i-H
"

CM
ON
r-H
"




O





T-l
00
S


a


0 0
00 CM
CO CO
CM in
i-i


o





§



o
CO

l-l
r-t


O
O
o

f^

o
o
o
o


o




?
S


&

u
u
I


m r^.
oo r-»





CM

O

r-l






CO





•







CM










a
^ ON
O O
i-4 r-t
X K
• **^
i-H CM


ON
O
r-4

M

CO
CM
ON
0



O


X
OO
CO
o
o
i-H


CM
O
0

.
CM



m

'B
§
^
yi
&j
^
e
o
3




























CM
•W
H
(Q
3

«•
3
~









                                                                                                                                                                                                               ti    01
                                                                                                                                                                                                               S    5
                                                                                                                                                                                                               2    "
                                                                                                                                                                                                               &   «
                                                                                                                                                                                                                          •S
                                                                                                                                                                                                                           c
§
i:
U    9
                                                                                                     101

-------
a
2
o
H
H
05
H
H
O
JB
O
H
D
W
U
EH
W
EH
<
EH
CJ
 C
 0)
C O^— '
a v -M
u 3 'g


o
"E §
CO .H
^ 4J
g rt
CTJ -H
cn cu
P

ti -H $

u
4J
II
*J s
•H
<
0) CD

> as



-H iH
1


Js
g>
cy v





3


0 0
rH UO



O



o
CO


o
CO
CO

CN
00
CO



o
CO

un



CO



9
^



£

0 0
f-x rH



O
O



O
rH
cn


o
CN

0
-d-
CO


o

cn"



o
cO


$
"- '



co

£g



CN
O



m



rH







CO



rH
rH
O


P
*-"



CO
H

CN CN



O
O



CN
vD



CN
O

O
•




°.



cn
o
o


p
•~-f



CO

0 0
CO 
o >n



o
CN|



O
rH
m


o
cn
CM

rH
CO
"


0

cO




rH


r?
^^



1
H

O 0



0



o
CO


o
CM
rH

CN
CN



o

CN




CO
rH

rf
^


SB
r

cn ^0
m CN



00



o
o



o



O

CT\




rH


C>0
'*-'


.


3
O



0^



CO







CO



C*J
uO







a

o o
r- 1 rH
X X
in r*-
in o
CT-
o
X
CN



CT-
o
CO

o
X
CN
O
i-i
O
r-l


CN
O
0

X

CM



rH
g
rH

§


0
4-1
1
                                                                                                                               o>  C
                                                                                                                           i-t   H  4J

                                                                                                                           W   «  0)
                                                                                                                               S  1
                                                                                                                               O  O
                                                           102

-------
U


X
•H
T3


(U

ft
di
a S3

CJ 
rH |

!> (S

Js


1.
•H «-*
d a)
a"


« S
ki
u u
eo n
5*





§§

CM



8



O
rH



0
cn
rH
CM


vO
vO

f*»

0
cn
P."


s



t-i
f




to



O 0

r-T



O




O
a



o

rH


O
O

m

o
•n


o
o



r-l
f



»
>




VO CM
0 0


ON
O




CM
-d-
CD




00
o


rH

rH


rH


CM




H




H




en o
o o


vO
0




CM
d




CM
en
o


m
o

rH


i-H

00
o




H



CO
S



o o
•st VO
I-l



0
o



o
ON
rH



O
en
i-H


o
o

en

o
o
en"


8



r?
f



rj
g



IncS
m CM




OO




0
CM




O
in


Q

00

o
o
r-l


S



rH
$



U
$



O 0
at in




g




O
CM




O
m
OO


o
cn
00

rH

O
vD
CM


O
en



3
$




S



0 0
CM r3
m CM



0



o
vO
cn



o
OO
cn
"d"

o
00

rH

o
CM
S


S



rH
$



Q
8



°°
rH s±
rH



O




O
ON




O
ON


O
rH

r-4

§
rH


0



H
t



z
A



O O
ON cn




O
m




o
vO
vO




S
p-


0
i-H
o

rH

O
o
rH


O
ON



H
f


f.
i
g



O O
en 1-1




m




0
vO




0
m


m

ON


CO
ON


m



p
f


^
g
H



OO CM
sj- r3




ON




O
rH
en




S
m


vO
o
rH

r-t

^
J


O



H"
f



H
•A



O O
rH OO
m CM



o
00




ON
cn



o
OO

                                                 103

-------
CJ

X
•H

"S
0)
ft
a-   i
u wo
d p*-'
SO) 4J
•o -<
Ml
i d J
m o
a* u
A
tandard
viation'
CO $
o



1736
£§§
C0.fi «
3 h


u
Ithmatl
Mean
h
^




.1*


Jj
I'-




ll



n u
4J 4J
H
II
!>



o o
8 a


in





o
a.
"



o
o






CM
CO
cn


o
3





3



*-.
^
f


CO
CO


o o
ON m
cn


s
00





s




o
CN
cn






o
3


O





O
cn



^
.^
f

CO
s


33
rH 0


CM
O





M9




*






2


§





es
0





ft


S


f-i in
0 CM
rH O


3
o





2




00
o






CT>
00


O





rH
O





**

V)
fi


0 Q
CM O
•> *
*Cf r-4


O
cn
r-*





§




S
-*_






8
00








1



^
*^
f

„
g


CN


3





o




§






o
o_


§
OO
rH





0
cn




o
i-H
r-i






O


8





O
rH
cn
rH



^
^
f

fi
8


II
CM


O
m





§
CO




0
CM
0
cn






o
CM


O
S





o



x-v
^
f

K
H


O O
m rv


•st
CN





o
t-H




O
rH






O
O


O
GO
CM





O
rH



x-v
^
f

JP
f


m cn
eo cn


o
cn










o
g









o
00





o
3



/-,
—
I1

sf
1
H


O 0
OO CM
CM


in





o




CO






CM


CN
Oi





O
0



x-s
^^
ff

g
•H
N


O O
OO 00
ON cn


I
i-H





O
00
rH
oo"



o
in
CM
i-H






O
o
cn


o
o
cn





o
o
o
tn

i
^

>*
•H
|
1
S
o


oo r^


m
CM
O





 tJ
rH S
* «
o a)
4-1 0)
o
43 T)
a)
00 4J
cJ x:
•ri QQ
•O i-l
0 >
y
y 4i
m js
4J
a. o
ra C
,C >H
U U
d) «
^ » •$
rH M 4)
C T3
1 -H
*~J J2 &
H |j o
V* 0)
0) rl
CO 4J 0}
2""1 g"
 s e
a r-( fl
J * p
! J 8
tn £ oi
352








                                               104

-------
H
«
H
H
U
ffi
U
O

CO
EH
A
D
CO
CO
H
EH
CO
O
 C
 0)
 ft
C CJ-.P*'
O 0) 4J
M T3 -H
OJ -H £
*v *s 3
in o

O
"S 0

n «
4-1 >
Q
*0 *H^

-C 6 n



u
•r4
W
«) c







cd rt


Si


i U
B 3
C M
**

V 0)
m Q
5 §
•u h




o o
OO 00




o
o




o
00


en

-d-
CM



O

°x
vO

O
VO
en
*



o

-------
                             APPENDIX D

             ACTIVATED SLUDGE MATERIAL BALANCE EQUATIONS
Cell yeild coefficient, biodegradability factor,  cell  retention  time,
and aerobic stabilization rate* are dynamic parameters describing "fill
and draw" activated sludge systems.  Their definitions and  calculations
are given by the following equations.

Cell Yield Coefficient, Ky;  Empirical constant that represents  the
sludge that is formed by conversion of BOD5 to cellular solids,

         AMLVSS = Ky (ABODs) -  (MLVSS)(C)(k )                  (1)
                   [AMLVSrl   [AMLVSsl
                   ABODs J   |_ABODs J
y   i —J-..^. i   , i .-.I.-JAJ..^_ i  /,-,',/,>                  ,_.
where        Ky = cell yield coefficient
         AMLVSS = average change in MLVSS per unit  time,  day

          ABODs = average removal of BODs per unit  time,  day  :

          MLVSS = average total mass of volatile solids in  system,  gm
              C = biodegradability factor
             k  = endogenous respiration rate, day

Biodegradability Factor, C:  The portion of activated  sludge  mass  that is
biodegradable.. C is not constant for all sludges but  varies  inversely
with sludge age.

                  (MLVSS)o - (MLVSS)n
              C ~~       (MLVSS) o                                (  '
*Theory and equations derived by M. Floyd Hobbs,  FMC  Corporation,  San
 Jose, California, 1973.  Unpublished work.

                                    106

-------
where         C = biodegradability factor

        (MLVSS)  = initial mass of volatile suspended solids, gm

        (MLVSS)  = nonbiodegradable volatile solids as determined by
                  aerobic stabilization, gm

Cell Retention Time, Qc:  Average residence time of activated sludge in
the system.

             0  = 		                         (4)
              c   (MLVSS)w +  (MLVSS)e


where        0  = cell retention time, day

          MLVSS = average total mass of volatile solids in system, gm

         MLVSS  = average mass of volatile solids wasted per unit time,
                  gm day

         MLVSS  = average mass_of volatile solids in effluent per unit
                  time, gm day

Aerobic Stabilization Rate, R:  Rate of reduction in sludge mass per
unit time due to biological oxidation of biodegradable sludge components.

Aerobic stabilization or aerobic reduction of biomass is based on
endogenous respiration of the bacterial mass.  This phenomenon occurs
during all phases of bacterial growth and only becomes predominant when
the carbonaceous nutrient level in the environment is insufficient to
support the living biological mass.  Under these conditions, cell death
and lysing exceeds cell growth.  Consequently, bacteria utilize stored
food within their cells or biological solids obtained by lysing of other
bacteria that have died.  In this manner, the cell mass is reduced to
material that, in essence, is nonbiodegradable.  Thus, aerobic stabiliza-
tion is the reduction in sludge mass caused by the biological oxidation
of sludge of reduced concentration that is not readily oxidized by
bacteria.

This phenomenon can be expressed mathematically by the following equation:
                   rdml                                       fc)
        R = kera = -[dtl                                       (5}

where         R = aerobic stabilization rate, gm day

             k  = endogenous respiration rate, day

              m = total biodegradable sludge mass, gm

             —- = change in biodegradable cell mass per unit time, gm days
                                   107

-------
Rearranging and integrating this equation gives:

                     M
       R = -k t = In -^                                        (6)
             e       M
                      o

where        M  = total biodegradable cell mass at given time, t, gm

             M  = initial biodegradable cell mass at zero time, gm

              t = time, day

The biodegradable mass present at a given time  is approximately equiva-
lent to the difference between the total mixed  liquor volatile suspended
solids and the mass of stabilized or nonbiodegradable volatile solids.
This is expressed as follows:

             M  = (MLVSS)  -  (MLVSS)                           (7)
              T-.          L.          II

where  (MLVSS)  = total mass of nonbiodegradable matter, gm

Substitution of Equation 7 into Equation 6 gives the following expression
in common log form:
                             (MLVSS). -  (MLVSS)
       R = -k t = 2.303 log 	 t	^n               (8)
             S               (MLVSS)  -  (MLVSS)
                                   o          n

Equation 4 expresses aerobic stabilization rate in measurable quantities.

The half-life time  (TjJ required to reduce by 50 percent any given  quantity
of biodegradable sludge mass can be calculated  by the following expres-
sion:
                  0.693
             T, =
                    k
                     e
The above expressions appear to be applicable for the design of batch
homogeneous reactors or continuous plug-flow reactors such  as  longi-
tudinal flow baffled or tubular reactors.

                                    108

-------
s
H
H
W
Q
^

H
Pn
§


g

t§
W
X
•H
•O
c
1)
Of
                                        sf
                                                  109

-------
w
X
•H
cu
&
OH
     11

     1
                                                      110

-------
o
S3
m
w
§
W
H
En
W
S
6-i
O

C/3

S
D
W
W

 X
•H
•o
 c
                                                     111

-------







a
H
H
CO
EH
FIELD
Q
<
S
s
<
1-1
fe
o
CO
§
w
§

w
X
T3
0)
ft
£







fl
m 0
CN
"2


3
fl O

Ol 1



to j
fN O

in

in
m

in
vO
vD


0

,_,

in
O
vO


O
r-


00
f=
tO
CO
>
^
0
<*
o
PI
r-H
•^T
0
ro


<*
*T
O
m

r--
m
O



bC
E
U
g
CO
ro
O
r-t
CO
vD

CN

0
in

O
CO
s

m
(N

p-H
^D

m

CN
,H
.

vD
CN


00
E
U
8
m
•y
o
£
-
o
(N

CN

O
(--
vD
m

o
CO
r-t
i

0
m
CO


o
o

c-i

0
01
r-
CO

0
iH
^r


00
E
lA
Q
S
O
fN
0
S
m
r-
CN
O
^H
m

n

o
o
^
0
01

o
01
00
o

S

&
o
^
CO
m

0
T
,
-1
0
T
CN


t
Q
O
u
o
CO
§
CN
CN
CN
O
fN

P-.

m
^
fN
ffl
(N

0
(Ji

0


o
m

kD

0
ro
in
rsi
IT
rr


00
e
z
H
r^
m
^r
m
m
CTi

\D

m
r-
rH

0
•j
CN
r--

O
ID

"
1^1
cn

m
^
m
m
CN
m
CN
in
1)


f
Z
I
f
*
O
CO
U"l
O
o
0
1— 1
r-.


**
r^
Q
Z

m
r-v
Q

CO


0
vD

Q

•^1


O
\£>


»
g'
1
H
CO
CJ^
CT>
r-
CM
m
CN
CO
*f


cn
r*
O

p-
r-
o

T
CO
m

cr>

in

vo
CO
CTi

in
ro



33
Q.
o
o
o
iO
^H
8
ro
0
0
o
m
o
0
•H

0
in
m
O
O
8
CO
O
o
m
o
o
r-.
O
o
in
f

O
CO
r\
0
O
m
o
0
0^
o
c
o
lT>
l/l
o
0
•^

1
4J
| Conduct i\
in
•*
<&
O
m
"


CO
m

S
H

O
M)
M)

ro

r~j

yD
r-


CN
m


§
Z
N
m
T
oi
^
m
r-
>£


oi
cn
CN

r-
co
•^r

c
ci

rn
10

kD
m

en
r~-
m

0>

01
e
CD
T3
^
| Formaldel
r^
o
0
CN
CO
m
fN
CN



0
m
„

O
T
T

0
•^1
^

O

0

0
in
o

0
CO
<"S)

g

f Turbidity
!
i
m
CO
c
X
If)

1
1

i
in

i
i
j

|


C)
M
o
U>
1
'
1
cl

i
G
O
O
2
o>
2:

Q
<4-l
C
o


o
•<»



'

v£>
*>

^
ro
r»i

T
r-l





iD


fi^

C/l
H

J
c.

^D
CN

•^J1



1
(


CN


vO


1—1



1



^
00
E

Q
O
03
0>
^
03
U

1

0
^D






>i>


•51


"






vD
E
O
O
£
2
|
1-
"c
u
OJ
^
CI
o

























t
w
to
b
c

o
CO
en

»
CN



in


S


CO
0>
0


Oi
m



0


ID
r^

^
a
o
>
a
0
(1
3
__,

n



O



D
^1
•-I


(T.
-H

0>


^1


O
CTi
1—1


^


l/>


&
Jd
n
u
^:
O
>i
t-i
Q
^T
CO
O
O
i-H



O


X


o


lO



CO


r-
co


E
b
^

X
O
(0
z
o
CO

i£
ro


•^T


O>


"5T


m
m



en


en


£
Oi
^

CJ
o
n)
z;

^

m


1*1





\o
^r

m






T

M
X
S

M
G.
112

-------
g
H

W
H
H
H
§
w

s
D
H



•H
                                               113

-------
                                  TECHNICAL REPORT DATA
                           (Please read Instructions on the reverse before completing)
1. REPORT NO.
      EPA-670/2-74-056
                             2.
                                                           3. RECIPIENT'S ACCESSION-NO.
4. TITLE AND SUBTITLE
 DEVELOPMENT OF ON-SHORE TREATMENT SYSTEM FOR SEWAGE
 FROM WATERCRAFT RETENTION  SYSTEM
                                                           5. REPORT DATE
                                                             July 1974; Issuing Date
             6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
 James H.  Robbins and Arthur  C.  Green
                                                          8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS

 FMC Corporation
 Advanced Products Division
 San Jose, California  95108
                                                           10. PROGRAM ELEMENT NO.
              1BB038/ROAP 21-BBU/TASK 03
             11. CONTRACT/GRANT NO.

                       68-32-0220
12. SPONSORING AGENCY NAME AND ADDRESS
National Environmental Research  Center
Office of Research and Development
U.S.  Environmental Protection Agency
Cincinnati, Ohio  45268
             13. TYPE OF REPORT AND PERIOD COVERED
                         Final
             14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
16. ABSTRACT
 A two-phase program developed  and  demonstrated a new method  for on-shore treatment  of
 sewage from recreational watercraft.   Phase I characterized  wastes and chemical
 additives associated with recirculating/retention systems.   Statistical analysis
 determined probable ranges of  waste characteristics as a function of watercraft type
 and  location.  Typical wastes  had  suspended solids and biochemical oxygen demand of
 2000 mg/1.  Respirometer studies evaluated toxicity of additives to activated sludge.
 Treatability of chemical/sewage mixtures was determined from pilot-scale activated
 sludge plant operations.  Cell yield  coefficients were calculated.  Photomicrographs
 recorded physical changes to activated sludge.  Concentrations  greater than 20 mg/1
 zinc or 120 mg/1 formaldehyde  caused  adverse effects to the  activated sludge process.
 Phase II field tested full-scale physical-chemical treatment equipment operating on
 watercraft wastes.  Average removal efficiencies for suspended  solids, biochemical
 and  chemical oxygen demand, phosphate, and zinc were greater than 90 percent.  Efflu-
 ent  coliform was less than 10  MPN/100 ml.  Discharge solids  were nonodorous and
 innocuous.  Postchlorination increased total-nitrogen removal from 30 to 70 percent.
 Operating costs were determined.
17.
                               KEY WORDS AND DOCUMENT ANALYSIS
                  DESCRIPTORS
                                             b.lDENTIFIERS/OPEN ENDED TERMS
                          c.  COSATI Field/Group
 *Waste treatment, Sewage treatment,  *Zinc,
 *Formaldehyde, Toxicity, Operating costs
*Physical-chemical sew-
age treatment,  *Marine
sewage  treatment,  fold-
ing tank,  *Chemical
additives,  Recreational
watercraft  sewage, Pump
out wastes,  Post chlori-
nation	
13B
18. DISTRIBUTION STATEMENT
        RELEASE TO PUBLIC
                                              19. SECURITY CLASS (This Report)
                                                   UNCLASSIFIED
                           21. NO. OF PAGES
                                  124
20, SECURITY CLASS (Thispage)
     UNCLASSIFIED
                                                                        22. PRICE
EPA Form 2220-1 (9-73)
                                            114
                                                      S. GOVERNMENT PRINTING OFFICE. 197'*-757-58l4/5330 Region No. 5-11

-------