WATER POLLUTION CONTROL RESEARCH SERIES 16070 DCD 09/70
The Oxygen Uptake Demand
of
Resuspended Bottom Sediments
ENVIRONMENTAL PROTECTION AGENCY WATER QTJAT TTV
ljllY OFFICE
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WATER POLLUTION CONTROL RESEARCH SERIES
The Water Pollution Control Research Series describes
the results and progress in the control and abatement
of pollution in our Nation's waters. They provide a
central source of information on the research , develop-
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Reports should be directed to the Head, Project Reports
System, Office of Research and Development, Water Quality
Office, Environmental Protection Agency, Room'1108,
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THE OXYGEN UPTAKE DEMAND OF RESUSPENDED
BOTTOM SEDIMENTS
by
Seattle University
Seattle, Washington
for the
WATER QUALITY OFFICE
ENVIRONMENTAL PROTECTION AGENCY
Program No. 16070 BCD
Contract No. 14-12-481
September, 1970
For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 - Price 50 cents
Stock Number 5501-0124
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EPA Review Notice
This report has been reviewed by the Water
Quality Office, EPA, and approved for publication.
Approval does not signify that the contents
necessarily reflect the views and policies of
the Environmental Protection Agency, nor does
mention of trade names or commercial products
constitute endorsement or recommendation for
use.
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ABSTRACT
A laboratory study has been conducted to show the application of
the Warburg respirometer in evaluating the influence of light, NaCl,
dilution salts, temperature and agitation on the maximum oxygen uptake
rate of disturbed bottom deposits. Experiments were conducted on
estuarian benthic material obtained from Bellingham Bay, Washington.
In all experiments the initial oxygen uptake rate was the
maximum uptake rate. Results obtained using distilled water as the
suspending medium were not appreciably altered due to the addition of
B.O.D. dilution salts, or NaCl in concentrations less than 30,000 mg/£.
The initial uptake rate also appears to be insensitive to light.
Ambient temperatures were varied from 10°C to 20°C and agitation
settings were varied from instrument maximum to twenty-five percent of
maximum. The Squalicum Creek sample showed variations in initial up-
take from 1,956 to 56,760 mg/fi, of oxygen per hour. The Whatcom Creek
sample had a range of from 2,784 to 83,040 mg/£ of oxygen per hour.
Results indicate that the maximum uptake rate is very sensitive
to temperature, degree of disturbance, and the total volatile solids
concentration of the benthic material.
Agitation alone was shown to .account for at least a ten fold
increase in the maximum oxygen demand.
This report is submitted in fulfillment of Project 16070 DCD,
Contract No. 14-12-481 between the Water Quality Office and Seattle
university.
Key Words: Benthic sludge, Warburg respirometer, B.O.D.,
estuaries, dissolved oxygen, sediment, Bellingham
Bay, sludge.
ill
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CONTENTS
Section ££&£.
I Conclusions 1
II Recommendations 2
III Introduction 3
IV Nature and Scope 5
V Methods and Instrumentation 6
VI Results and Discussion 8
VII Acknowledgements 34
VIII References 35
IX Glossary 37
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FIGURES
Page
1 Oxygen Uptake Study for the First Squalicum Creek Sample 10
2 Replica Agreement for the Second Squalicum Creek Sample 11
3 Enveloping Curves Showing Variations in Maximum Oxygen
Uptake as a Function of Temperature and Amplitude Setting
for Squalicum Sludge 15
4 Oxygen Uptake Study, Squalicum Creek l6
5 Oxygen Uptake Test on Squalicum Sludge Using Distilled
Water and Sodium Chloride as Dilution Mediums 18
6 Long Term Oxygen Uptake Analysis for Squalicum Creek
Sludge Using Sodium Chloride and Distilled Water as
Dilution Mediums 19
7 Light and Dark Oxygen Uptake Tests on Squalicum Sludge
Using Distilled Water and Standard B.O.D. Dilution
Water as Suspending Mediums 21
8 Oxygen Uptake Study for the First Whatcom Creek Sample 23
9 Enveloping Curves Showing Variations in Maximum Oxygen
Uptake as a Function of Temperature and Amplitude Setting
for Whatcom Sludge 2?
10 Long Term Oxygen Uptake Analysis for Whatcom Creek Using
Sodium Chloride and Distilled Water as Dilution Mediums 29
11 Oxygen Uptake Study for the First Whatcom Creek Sample
Using B.O.D. Dilution Water and Distilled Water as
Suspending Mediums 31
vi
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TABLES
Least Squares Analysis of Data Defining a Functional
Relationship between L and Sludge Concentration
for Squalicum Creek 12
Two Way Classification for Slope Coefficients Used to
Relate L and CB 13
Least Squares Analysis of Data Defining a Functional
Relationship -Between Maximum Oxygen Uptake Rate and
Sludge Concentration for Squalicum Creek 14
Least Squares Analysis of Data Defining a Functional
Relationship Between Maximum Oxygen Uptake Rate and
Sludge Concentration for the First Whatcom Creek Sample 24
Least Squares Analysis of Data Defining a Functional
Relationship Between Maximum Oxygen Uptake Rate and
Sludge Concentration for the Second Whatcom Creek
Sample 25
Oxygen Uptake Studies for Light and Dark Studies on
the First Whatcom Creek Sample Using a Distilled Water
Medium 33
VII
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SECTION I
CONCLUSIONS
1. The oxygen demand of resuspended bottom sediments can be determined
by using the Warburg respirometer. The instrument is especially
useful for determining maximum oxygen uptake rates.
2. The magnitude of the maximum oxygen uptake rate is sensitive to the
elapsed storage time of the samples. Storage at 4°C does not
eliminate this problem.
3. The bottom sediments tested in this study did not require external
seeding to initiate the biochemical reaction. No lag phases were
encountered in any of the experiments.
4. Distilled water was used as the suspending medium in this study.
Maximum oxygen uptake rates were not changed when the suspending
medium was modified by introducing NaCl (concentrations up to 30,000
mg/&) or B.O.D. dilution salts.
5. Maximum oxygen uptake rates of bottom sediments do not appear to be
light sensitive.
6. The magnitude of the initial oxygen uptake rate is sensitive to
temperature and degree of agitation.
7. Suspension can increase the quiescent, maximum oxygen uptake rate by
more than a multiple of ten.
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SECTION II
RECOMMENDATIONS
This investigation has demonstrated that the oxygen demand of re-
suspended bottom sediments is different than those noted while the
material remains quiescent. Of particular interest is the fact that
uptake rates observed in the suspended state are exceedingly high com-
pared to observed quiescent rates.
The oxygen demand rate of disturbed bottom sediments could signi-
ficantly affect the dissolved oxygen concentration of estuaries during
periods of dredging. This phenomena would be particularly serious in
estuaries where tidal action promotes suspension for prolonged time
periods.
Any anticipated dredging operation should be preceded by efforts
to determine the resulting effect on ambient oxygen concentrations. The
Warburg respirometer and the methods outlined in this study provide a
means for approaching the problem. At the very least, the Warburg ap-
proach can be used to anticipate the maximum and minimum effects on
estuarian oxygen concentration due to dredging operations.
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SECTION III
INTRODUCTION
The influence of biochemical oxygen demand (B.O.D.) on ambient
oxygen concentration has long been a subject of interest to environ-
mentalists concerned with obtaining a more comprehensive knowledge of the
dissolved oxygen problem. Recent literature has indicated a revived
interest in the effect of benthic B.O.D. on the oxygen concentration of
the overlying water.
The removal of oxygen due to the microbial respiration of benthal
deposits has been recognized for many years (1) (2). In principle the
mode of oxygen removal by benthic deposits is caused by one, or a combina-
tion of, the following.
1. B.O.D. may be introduced from the benthal deposits by scour (3)
(4).
2. Oxygen may be consumed by the gases which are produced by
anaerobic decomposition and rise from the benthal layers (5)
(6) (7) (8).
3. Oxygen may be consumed by the soluble end products of benthal
decomposition which diffuse into the overlying water (5) (9).
4. The oxygen demand of the sludge itself.
Many studies have been made in an effort to identify the prime
variables which might affect the rate of benthal decomposition. Investi-
gators have studied the possible influence of: (a) light, (b) salinity,
(c) sludge depth, (d) oxygen concentration in the overlying water, and
(3) season and temperature.
Recent work by Hanes (10) has indicated that the benthal oxygen
uptake rate is independent of oxygen concentration. Subsequent work by
McDonnel (11) indicates that oxygen uptake rates are indeed dependent on
the overlying oxygen concentration. The controversy is whether or not
the oxygen uptake is controlled by the rate of transport of oxidizable
materials from the interior of the deposits to the overlying water or by
the rate of diffusion of oxygen into the deposit.
Other work by Hanes (12) suggests that the oxygen uptake rate of a
benthal system increases with increased concentrations of sea water, and
also increases with the addition of B.O.D. nutrients to the system.
Oldaker (13) indicates that the benthic oxygen demand varies with
sludge depth. His work also suggests the importance of benthic nitrifica-
tion to the oxygen budget.
The maximum oxygen uptake rate has been used by both Hanes and
McDonnell to evaluate the influence of temperature, sea water and added
nutrients on the oxygen demand of bottom deposits. Both investigators
have expressed oxygen uptake in units of mass per area per hour. The
area concept is poor. It does not permit the results of different in-
vestigators to be compared.
Past studies conducted to determine the oxygen demand of benthic
-------
materials have been designed so that the sediment remains stationary,
while the overlying water has an induced velocity gradient. It is
obvious that bottom sediments are frequently resuspended by flood flows
dredging and scouring action. The question is raised, "does the in- '
creased surface area, caused by resuspension, create an oxygen demand
significantly exceeding that observed in the quiescent situation?" If
resuspension is a significant factor the act of dredging might seriously
affect ambient oxygen concentrations in many estuaries. A survey of the
literature suggests that this aspect of the benthic problem has not
received attention.
It is the purpose of this paper to evaluate the use of the Warburg
apparatus in determining the oxygen uptake demand of disturbed bottom
deposits and to determine if resuspension significantly alters the
oxygen demand rate of benthic material.
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SECTION IV
NATURE AND SCOPE
The purpose of this investigation is to examine the oxygen uptake
rate of resuspended estuarian bottom sediments. Particular interest is
directed toward observing the change in magnitude of the maximum uptake
rate due to changes in ambient temperature, NaCl concentration, and the
presence of B.O.D. dilution salts, while the benthic material is exposed
to various states of agitation. These parameters are selected for study
because of their possible influence on the rate of oxygen depletion in
estuaries due to the resuspension of bottom sediments during periods of
intense dredging.
The Warburg apparatus was chosen as the instrument best suited for
this study. The number of simultaneous experiments which can be run on
the instrument provides a good capacity for exposing several replicas to
parametric variations. The instrument also has excellent thermal control,
a means for varying agitation and an illumination system for light and
dark studies.
Bottom samples used during the study were collected from Bellingham
Bay on January 14, 1969,and on March 21, 1969. This sampling site was
selected-because information made available by F.W.Q.A. (14) indicates
that the Whatcom Creek and Squalicum Creek areas of Bellingham Bay con-
tain extensive bottom deposits capable of exerting high biochemical
oxygen demands. Bellingham Bay, being only a ninety minute drive from
the laboratory, provided both a convenient and significant sampling site.
The oxygen uptake of these samples is studied using three suspend-
ing mediums: distilled water, B.O.D. dilution water and salt suspensions
up to 30,000 rag/A of NaCl. Ambient temperatures are varied from 10°C
to 20°C. Agitation is accomplished by varying the eccentricity setting
of the Warburg cam. The entire eccentricity range has been observed.
The possible influence of light on the oxygen uptake profile has also
been examined.
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SECTION V
METHODS AND INSTRUMENTATION
SAMPLE STORAGE
Sludge samples were returned to the laboratory within twelve hours
of collection. Bottom material was retained in polyethylene containers
and stored at 4"C until required for testing.
DILUTION MEDIUMS
There were three basic dilution or suspending mediums used during
the test sequence.
Distilled Water - Distilled water was obtained from a standard,
single-stage distilling apparatus.
Sodium Chloride - Sodium chloride suspensions were made by dis-
solving the required weight of sodium chloride crystals (reagent grade)
in distilled water.
Dilution Water - Standard dilution water was used as described in
Standard Methods (15) under the section discussing procedure for testing
biochemical oxygen demand.
THE WARBURG APPARATUS
A Gilson (RWBP 3) Warburg apparatus was used during this study.
This instrument is refrigerated and is equipped with a bank of 30 watt
reflector spotlights for light and dark studies. Temperature is con-
trolled to within + 0.05°C.
The reaction vessels have a 125 ml capacity. Brodie solution was
used as the manometric fluid and a 10% KOH solution was used in the cen-
ter well to absorb carbon dioxide.
Flask calibration constants were obtained using the mercury
method.
There are two settings on the instrument which determine the degree
of flask agitation. The first is the number of shaft revolutions per
minute. This variable was fixed during the entire test series at 110
revolutions per minute. The second is the cam or amplitude setting which
is controlled by a set screw. The degree of eccentricity was set in four
equal steps from minimum to maximum. In this report the set screw posi-
tions are referred to as 25, 50, 75 and 100 percent maximum amplitude.
WARBURG TEST PROCEDURE
One of the prime variables which has to be determined for each
test run was a measure of the sludge concentration in the reaction
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vessels. The magnitude of this variable was calculated by making a
series of dilutions using wet sludge. The concentration range on a set
sludge basis varied from 10,000 to 100,000 mg/Jl. Portions of these
mixtures were subjected to a total volatile solids analysis, and the
final sludge concentration was recorded in mg/SL of total volatile
solids (T.V.S.).
A 30 c.c. syringe, without needle, was found to be the most
efficient and reproducible method of introducing the material into the
reaction vessel. The entire 30 c.c. volume was placed in the vessel.
When conducting a Warburg run, the instrument was allowed sufficient
time to reach thermal equilibrium before the reaction vessels were placed
on the manometer stems.
LIGHT AND DARK STUDIES
Several experiments were run during the test sequence to determine
if the presence of light significantly influenced the rate of oxygen up-
take. When these tests were conducted,replica reaction vessels were
placed on the manometer stems. One flask was wrapped in two layers of
aluminum foil while the other was left unmodified.
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SECTION VI
RESULTS AND DISCUSSION
The results presented in this section reflect oxygen uptake
studies conducted on bottom deposits obtained from Bellingham Bay.
Samples were collected at the mouth of Squalicum Creek and Whatcom
Creek. All analyses were made using facilities at Seattle University.
SQUALICUM CREEK SLUDGE
Samples were taken at the Squalicum Creek station on January 14,
1969, and on May 20, 1969. Warburg studies were conducted at several
temperatures and agitation settings using distilled water and NaCl
solutions as dilution media. Samples were also subjected to light and
dark studies to determine if light significantly influenced reaction
kinetics,
Distilled Water .as _a Dilution Medium - Warburg studies for both
Squalicum Creek samples suggest that the initial biochemical reaction
can be approximated by first order kinetics when distilled water is used
as the suspending medium.
For purposes of this paper, the first order solution is defined as:
where,
y =* oxygen consumed during elapsed time "t" in mg/fc,
LTTT_ = ultimate first stage oxygen demand in mg/£,
ULT
k = reaction constant in hours ,
t = elapsed time in hours.
Figure Number 1 is a typical Warburg study conducted on the first
Squalicum Creek sample, using an agitated and unagitated flask. Note the
substantially reduced oxygen uptake profile for the Warburg flask that
was not agitated.
The Thomas method (1) was used to calculate k and L^^. The maxi-
mum oxygen uptake rate is defined as:
= 2'3kLULT>
o
and is expressed in mg/il per hour.
The second Squalicum Creek sample was subjected to Warburg studies
-------
using ambient temperatures of 10°C, 15°C and 20°C. Figure Number 2 is a
typical run showing replica oxygen uptake profiles.
Table Number 1 is a tabulation of the ultimate first stage oxygen
demand as a function of temperature and amplitude setting. Table Number
2 is a two way classification of the slope coefficients given in Table
Number 1. Statistical analysis using the F-test at the 99th percentile
indicates that the ultimate first stage B.O.D. for the Squalicum creek
sample is independent at temperature and amplitude setting.
The mean value of LTTTr_ is 22.6 C_ and the associated standard
UL1 Ii
deviation is 3.2 C . The coefficient of variation for the data is ap-
proximately fourteen percent.
Table Number 3 is a summary of data relating maximum oxygen uptake
rate and the total volatile solids concentration of Squalicum sludge.
For a given concentration of T.V.S., the magnitude of the maximum oxygen
uptake rate appears to depend on both the ambient temperature and the
amplitude setting.
Figure Number 3 indicates how the amplitude setting influences the
magnitude of -^ for fixed ambient temperatures.
o
Figure Number 4 indicates an insignificant change in the initial
0 uptake curve during storage at 4°C. This is a very important point,
because any change during storage would require that all measurements be
adjusted for elapsed storage time.
-------
35,000 |-
30,000
25,000 -
20,000 _
CM
O
O
<=«
60
C
H
D
QJ
15,000 -
10,000 -
5?QOQ
y - 37,322 [1 -
21,000 rng/H per hr. of
Test Conditions
Temperature 2Q°c
Dilution Medium - Distilled Water
Sludge Concentration - 2,000 mg/Ji T.V.S.
O - flask agitated
[j - flask not agitated
D
D
D
I I
I I
elapsed time in hours
Figure No. 1 - Oxygen Uptake Study for the First Squalicum
Creek Sample.
10
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-T*- J « «
36,000
30,000
24,000
18,000
o-i
O
O
^ 12,000
e
c
H
0)
^ 6,000
c
£
O
a
^B
- o
Test Conditions
Temperature 20°C
g Dilution Medium - Distilled Water
Sludge Concentration - 2,000 mg/£ of
volatile solids
-
,11111 .1 1
1 2 J-3 4 5 6 7 8
elapsed time in hours
Figure No. 2 T-, Replica Agreement for the Second Squalicum Creek Sample.
11
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Table No. 1 - Least Squares Analysis of Data Defining A Functional
Relationship between LTJTT and Sludge Concentration for
Squalicum Creek.
Temperature Amplitude
°C % Max.
20 100
20 75
20 50
20 25
15 100
15 75
15 50
15 25
10 100
10 75.
10 50
10 25
Function
400 mg/£ < CB < 4000 mg/£
T.V.S. T.V.S.
LULT =
LULT =
LULT=.
LULT =
LULT =
LULT =
LULT =
LULT =
LULT =
LULT =
LULT =
LULT =
26.
19.
25.
19.
22.
18.
26.
18.
23.
23.
26.
21.
78
16
59
28
02
45
42
80
21
09
78
90
CB
CB
CB
CB
CB
CB
CB
CB
CB
CB
CB
CB
0
0
0
0
0
0
0
0
0
0
0
0
r
.99
.99
.99
.99
.99
.99
.99
.99
.99
.99
.99
.99
Illustrative Example:
The expected first stage B.O.D. for 2,000 mg/Jl T.V.S. of
Squalicum sludge suspended in distilled water at 20°C and
at full amplitude setting on the Warburg is:
LULT = 26'78 (
= 53,560 mg/Jl of 0
12
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Table No. 2 - Two Way Classification for Slope Coefficients Used To
Relate LULT and CB
Temperature
20
15
10
Amplitude
Mj2an
Amplitude in
25 50
19.28 25.59
18.80 26.42
21.90 26.78
19.99 26.26
% Maximum
75 100
19.16 26.78
18.45 22.02
23.09 23.21
20.23 24.00
Temperature
Mean
22.70
21.42
23.75
22.62
General
Mean X
13
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Table No. 3 - Least Squares Analysis of Data Defining A Functional
Relationship Between Maximum Oxygen Uptake Rate And
Sludge Concentration for Squalicum Creek
Temperature
°C
20
20
20
20
15
15
15
15
10
10
10
10
Amplitude
% Max.
100
75
50
25
100
75
50
25
100
75
50
25
Function
400 mg/S, < C < 4000 mg/Jl
T.V.S. T.V.S.
f ' U'19 °B
o
dJ = 9'77 °B
o
£ = 11-80 CB
O
dt = 6'32 CB
0
£ - U-32 CB
o
dt = 8'82 CB
o
f o II-09 S
f - 4'53CB
o
dt = 8'58 CB
o
^ - 8 23 C
dto 8'23CB
£ - *'* CB
o
to = 4'89CB
0
r
0.99
0.99
0.99
0.99
0.99
0.99
0.99
0.99
0.99
0.99
0.99
0.99
Illustrative Example:
The expected maximum oxygen uptake rate for 2,000 mg/S, .T.V.S. of
Squajicum Creek sludge suspended in distilled water at 20°C and
at fall amplitude setting on the Warburg is:
. 14.19 (2,000)
= 28,380 mg of 0^ per liter per hour
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14
13
12
11
I 1Q
^
-------
36,000
3Q,QOQ
24,000
18,QOQ
cs
O
W-l
O
e 12?OOQ
H
O)
1
I 6,QQO
&
o
/A
A jy\
A
A
^^k*
~ A
Test Conditions
Temperature 20° C
Dilution medium - Disti
Amplitude of 75% maximum
__ ^^ sludge concentration - 2
K
A Test Date - June 23, 196
__ ^ Teat Date - Sept. 2, 196
»
1 1 1 1 1 1 1 1 1
T.y.s.
oo
elapsed time in hours
Figure No. 4 - Oxygen Uptake Study, gqualicum Creek,
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Sodium Chloride Solution as a^ Dilution Medium - Experiments were
conducted to determine if the oxygen uptake profile would be significantly
altered by the presence of varying concentrations of sodium chloride.
The results of a typical experiment are shown in Figure Number 5.
The amount of oxygen consumed during the test period is greater for the
salt medium than for the distilled water medium. However, the initial
uptake rate is essentially independent of sodium chloride concentration
up to 30,000 mg/Jl.
Figure Number 6 is a comparison of two long term Warburn experi-
ments. The long term oxygen uptake profiles are influenced by the
presence of sodium chloride and the shaking rate.
17
-------
48,000
42,000
36,000
'30,000
24,000
18,000
o
o
a 12,000
0)
a
4-1
C
§0 6,000
&
o
: ':'
*
A Test Conditions
2 Temperature 20°C
Sludge Cone. 2000 mg/fi, T.V.S.
_ A Dilution Medium
W 20, .000 mg/ji , NaCl
Arap. of 75% maximum
Date - Sept. 3, 1969
Temperature 20°C
_ A . Sludge Cone, 2000 mg/£ T.y.S.
8 A Dilution Medium - Distilled Water
Amp, at 75% maximum
Date T-. Sept. 2, 1969
1
I I 1 1 1 1 1 1 l
CS
CO.
IT)
\O
00
elapsed time in hours
Figure No. 5 - Oxygen Uptake Test on Squalicum Sludge Using
Distilled Water and Sodium Chloride as Dilution
Mediums.
13
-------
^
o
03
O
o
0
,_)
H
0)
"««
£
0)
00
fr
o
130
120
110
100
90
80
70
60
50
40
30
20
-
0»
0
0
o
* o °
X* o o ° ° °°
$OO Test Condition
O Temp. 20°C
^ Sludge Cone. 2000 mg/Jl T.V.S.
A Dilution medium - 20,000 mg/2. NaCl
_ Amp. at 75% max.
_ Date - Sept. 3. 1969
W Temp. 20°C.
_ Sludge Cone. 2000 mg/Jl T.V.S.
^O Dilution medium - Distilled Water
Amp. at 50% max.
Date - Sept. 11, 1969.
1 1 I 1 1 1 1 1 1 1 1 1 I 1 1 1
eM'«*v00O O'CMStvOOOOCMSfvOOOO
CM
CM
CM
CM
elapsed time in hours
Figure No. 6 - Long Term Oxygen Uptake Analysis for Squalicum
Creek Sludge Using Sodium Chloride and Distilled
Water as Dilution Mediums.
-------
Light and Dark Tests - Figure Number 7 is a typical plot of data
obtained from Warburg studies where replica runs were made using foil
wrapped and unwrapped reaction vessels. There appears to be an insignifi-
cant difference between the oxygen uptake in vessels exposed to high in-
tensity light and those vessels where light has been essentially excluded.
Tests were also run using standard B.O.D. dilution water as the sus-
pending medium. As in the case of sodium chloride suspensions, the
oxygen uptake was higher in the modified suspension medium than in the
distilled water medium, but the initial uptake rates were similar.
Comment - It appears, for the experimental conditions imposed dur-
ing this investigation, that the accumulative oxygen uptake curve is a
function of T.V.S. concentration, temperature, agitation, and the nature
of the suspending medium. However, the initial oxygen uptake rate does
not appear to be significantly influenced by the presence of sodium
chloride in concentrations less than 30,000 mg/£ or by the presence of
dilution salts. The presence or absence of light does not appear to be a
significant factor in measuring the initial oxygen uptake for Squalicum
Creek sludge.
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70 r-
65
6Q
55
50
45
40
35
^ 30
I»A
£
o 05
to
o
o
S 20
c
H
8 15
«
4-J
3* n
* 10
&
o 5
& * *
^y /\
A ^\
6^ 8 8
"A . 8 8 °
: * s«80
A Test Conditions
A ^ Sludge Cone. - 2000 mg/£ T.V.S.
~ ^ Temp. 20°C.
^ Amp. 50% maximum
^ Date - Sept. 17, 1969
Dilution Medium - Distilled Water
_ £ Foil Wrapped
Q ONot Wrapped
~ Dilution Medium - Dilution Water
4^ Foil Wrapped
^^Not Wrapped
~*
0
-
i I 1 1 1 1 1 1 1
csj-vf vD OO O CM «tf VO 00
elapsed time in hours'"1
Figure No. 7 - Light and Dark Oxygen Uptake Tests on Squalicum
Sludge Using Distilled Water and Standard B.O.D.
Dilution Water as Suspending Medium.
2-1
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WHATCOM CREEK SLUDGE
Samples were taken at the Whatcom Creek Station on January 14,
1969, and on May 20. 1969. Warburg studies were conducted at several
temperatures and agitation settings, using distilled water and NaCl
solutions as dilution media. Samples were subjected to light and dark
studies to determine if light significantly influenced reaction kinetics.
Distilled Water as _a Dilution Medium - Warburg studies for the
Whatcom Creek sample suggest that the initial biochemical reaction can
be approximated by first order kinetics when distilled water is used as
the suspending medium. Figure Number 8 shows the results of a typical
Warburg study.
The first Whatcom Creek samples were subjected to tests at 20°C
and 10°C using several agitation settings. Table Number 4 is a least
squares fit of the data relating the maximum oxygen uptake rate to
temperature and agitation. The elapsed time during which these tests were
run was relatively short and oxygen uptake curves obtained at the begin-
ning of the test period were duplicated at the end of the test period.
Apparently storing the sludge for several weeks at 4°C did not produce
a significant interference.
The second Whatcom Creek sample was tested on the Warburg, and
the resulting least squares fit for maximum oxygen uptake is presented
in Table Number 5.
22
-------
CM
O
O
CO
O
O
O
-------
Table Number 4 - Least Squares Analysis of Data Defining a Functional
Relationship Between Maximum Oxygen Uptake Rate and
Sludge Concentration for the First Whatcom Creek
Sample
Temperature
°C
20
20
20
10
10
Amplitude
% Max.
100
50
25
75
25
Function
480 mg/£ < O, < 4800 mg/«,
D
T.V.S. T.V.S.
f- 21'8 CB
O
£ = 18'2 CB
o
f 9'9 CB
o
-^ =10.2 CB
o
4j - 9.46 CR
ut o
O
r
0.99
0.99
0.99
0.99
0.99
Illustrative Example:
The expected maximum oxygen uptake rate for 2,400 rng/5.
T.V.S. of Whatcom Creek sludge suspended in distilled water at
20°C and at 75 C amplitude setting on the Warburg is:
20 (2,400)
- 48,000 mg of 02 per liter
per hour.
-------
Table Number 5 - Least Squares Analysis of Data Defining A Functional
Relationship Between Maximum Oxygen Uptake Rate and
Sludge Concentration for the Second Whatcom Creek
Sample
Temperature Amplitude
°C % Max.
20 100
20 75
20 50
20 25
15 100
15 75
15 50
15 25
10 100
10 75
10 50
10 25
Function r
480 rng/A < C < 4800 mg/£
T.V.S. T.V.S.
&- = 17.3 Cn 0.99
at a
0
~Z- = 15.4 C,, 0.99
at o
o
& = 14.0 Cn 0.99
dt D
0
rfc - 10.0 CB 0.99
at o
o
§ = 12.0 C., 0.99
dt B
o
& = 12.6 C,, 0.99
dt o
o
^ = 11.4 CD 0.99
dt JB
0
dt = 9*5 CB °'"
o
f - 10'° CB °'"
o
f - 9'3 CB °'"
o
41 = 8.1 CB 0.99
at D
o
4s- = 5.8 C_ 0.99
dto B
Illustrative Example: See Table Number 3.
25
-------
Several months elapsed during this series of tests. The ultimate
first order B.O.D. did significantly change during this period. To com-
pensate for the storage factor, all data were adjusted to agree with the
data obtained at the beginning of the test period. The data in Table
Number 5 have been adjusted.
Table Number 4 and Table Number 5 indicate for a fixed C_ that the
initial oxygen uptake is sensitive to both temperature and agitation.
This observation is graphically illustrated in Figure Number 9. If the
data of Table Number 4 were plotted on this graph, different curves would
appear for the 20 C and 10 C temperature setting. This apparent incon-
sistency is readily explained by the fact that storage time for the
Whatcom Creek sample plays an important role in determining the magnitude
dv
of -rr . Since the two Whatcom samples were stored for different periods
° dv
of time before testing, the absolute magnitudes of -rr should differ,
o
but the relative influence of temperature and agitation should be, and
is, similar,
When the first order ultimate demand (Lm ) was calculated from
the data of the first Whatcom Creek sample, it is found that the lower
°
thermal environment (10C) yields an Ivr,T about fourteen percent lower
than that observed at the higher thermal environment (20°C) . A similar
analysis for the second Whatcom Creek sample yielded an eleven percent
difference. No such dependency between L.rrm and temperature was observed
for the Squalicum Creek samples.
-------
g
H
4J
tr
0)
I
18 _
16
14
12
10
0)
co
M-l csl
O O
Q) U-l
^t Q
O
CO 0
A
temp. 10 C
c
rH
O
Cxi
CO
00
amplitude setting in percent maximum
Figure No. 9 -
Enveloping Curves Showing Variations in Maximum
Oxygen Uptake as a Function of Temperature and
Amplitude Setting for Whatcom Sludge.
27
-------
Sodium Chloride Solutions as a_ Dilution Medium - Whatcom Creek
samples were tested in mediums containing up to 30,000 mg/& of sodium
chloride. As in the case of the Squalicum Creek samples, the sodium
chloride medium appears to have no significant influence on . .
However, the total oxygen uptake curve is significantly higher for the
salt medium than for the distilled water medium. Figure Number 10
shows a typical Warburg run comparing sodium chloride and distilled
water as suspending mediums.
-------
A
~6C
e
M-l
O
(0
O
o
o
rH
C
H
0)
J-l
P.
c
fit
0
190 r A
180
170
160
150
140
130
120
110
100
90
80
70
60
50
40
30
20
10
A
A
A
A
A
A
A
A
A -
A
*
/^A
t_^
~~ w Test Conditions
_ Jk Temp. 20°C
^ Amp. 50% max.
_ Date - Sept. 15, 1969
II Dilution Medium - Distilled Water
_ A ^Dilution Medium - 30,000 mg/£ NaCl
A Sludge Cone. 2,400 mg/S- T.V.S.
I | | 1 1 1 1 1 1 1 1 1 1 1
-------
J}.(3.J). Dilution Water as _a Suspending Mediimt - Figure Number 11 is
a Warburg analysis run to compare the use of B.O.D. dilution water and
distilled water as suspending mediums for Whatcom Creek sludge. The
data indicate little or no difference in the oxygen uptake profile for
the two mediums during the first six hours of experimentation.
30
-------
J.MU
130
120
110
100
90
80
70
^
$ 60
o
in
- 50
o
o
0
r-|
c 40
1
5 30
§
e
& 20
fr
o
10
_
O
O
0
o
o
Test Conditions
-
~ Temp. 10° C
Amp. at 25% max.
Sludge Cone. 2,400 mg/£ T.V.S.
Date April 4, 1969
A Suspending Medium
- O~ B.O.D. Dilution Water
A - Distilled Water
^^
f^
-
, II I 1 1 .._! 1 1 1
co
00
elapsed time in hours
Figure No. 11 - Oxygen Uptake Study for the ELrst What com Creek Sample
' Using B.O.D. Dilution Water and Distilled Water as
Suspending Mediums
31
-------
Light and Dark Tests - Table Number 6 presents a typical result
from a Warburg run using unwrapped and foil wrapped reaction vessels.
It would appear from these test conditions that no significant difference
in uptake kinetics exists due to the presence of light for elapsed time
periods up to eleven hours.
Comment - For the experimental conditions imposed during this
investigation the cumulative oxygen uptake curve appears to be a function
of T.V.S. concentration, temperature, agitation, and the nature of the
suspending medium. However, the initial oxygen uptake rate is not signi-
ficantly influenced by the presence of sodium chloride in concentrations
less than 30,000 mg/£ or by the presence of dilution salts. The presence
or absence of light does not appear to be a significant factor in measur-
ing oxygen uptake for Whatcom Creek sludge.
32
-------
Table Number 6 - Oxygen Uptake Studies for Light and Dark Studies on the
First Whatcom Creek Sample Using a Distilled Water
Medium
Test
Conditions
Temp. 20°C
Amp. 50% Max.
T.V.S. @
2400 mg/£
Time
(hrs.)
0.5
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
11.0
mR/fi,
wrapped
22,181
45,792
83,475
107,802
122,351
133,083
139,284
144,054
147,393
150,255
152,163
153,594
of oxygen
not wrapped
22,181
45,792
83,475
108,756
124,497
134,991
141,192
145,962
150,732
154,071
155,502
157,410
33
-------
SECTION VII
ACKNOWLEDGEMENTS
The guidance and assistance of Dr. Donald J. Baumgartner of the
WQO has been greatly appreciated.
Mr. Geza Palotas is deserving of recognition for his efforts in
obtaining the necessary laboratory data.
This work was supported in part by the National Coastal Pollution
Research Program, WQO, under Research and Development Grant No. 16070
BCD.
-------
SECTION VIII
REFERENCES
1. Schroepfer, G. J., "Pollution and Recovery of the Mississippi River
At and Below Minneapolis and St. Paul." Sewage Works Jour.. _3, 4,
693 (Oct. 1931).
2. Wisely, W. H., and Klassen, C. W., "The Pollution and Natural Puri-
fication of Illinois River Below Peoria." Sewage Works Jour.. 10. 3,
569 (May, 1938).
3. Streeter, H. W., "Measures of Natural Oxidation in Polluted Streams.
I. The Oxygen Demand Factor." Sewage Works Jour.. T_* 2» 2^1
(March, 1935).
4. Velz, C. J., "Factors Influencing Self-Purification and Their Rela-
tion to Pollution Abatement. II. Sludge Deposits and Drought Proba-
bilities." Sewage Works Jour..21. 2, 309 (March, 1949).
5. Baity, H. G., "Some Factors Affecting the Aerobic Decomposition of
Sewage Sludge Deposits." Sewage Works Jour.. 10, 3, 539 (May, 1938).
6. Henrici, A. T. and McCoy, E., "The Distribution of Leterotrophic
Bacteria in Bottom Deposits of Some Lakes." Trans. Wisconsin Acad.
Sci., Arts. Letters. JJ1, 323 (1938).
7. Lardieri, N., "Aerobic and Benthal Oxygen Demand of Paper Mill Waste
Deposits." Tappi. 17, 12 (1954).
8. Masselli, J. W., e_t al., "White Water Wastes from Paper and Paper-
board Mills." Report to New England Water Poll. Control Comm.,
Boston, Mass. (1963).
9. Fair, G. M., Moore, E. W., and Thomas, H. A. Jr., "The Natural Puri-
fication of River Muds and Pollutional Sediments." Sewage Works
Jour.. 13, 2, 270 (March, 1941).
10. Hanes, N. B. and Irvine, R. L., "Oxygen Uptake Rates of Benthal
Systems by a New Technique." Proc. 21st Ind. Waste Conf. Purdue
Univ., Ext. Serv. 121. 468 (1966).
11. McDonnell, A. J. and Hall, S. D., "Effect of Environmental Factors
on Benthal Oxygen Uptake." Jour. Water Poll. Control Federation.
_41, R353 (August, 1969).
12. Hanes, H. B. and White, T. H., "Effects of Seawater Concentration on
Oxygen Uptake of a Benthal System." Jour. Water Poll. Control Fed-
eration. 40, R272 (August, 1968).
35
-------
13. Oldaker, W. H., Burgum, A. A. and Pahren, H. R., "Pilot-Plant
Studies of Benthic Oxygen Demand of River Bottom Sediments."
Jour. Water Poll. Control Federation. .40, 10, 1688 (October, 1968).
14. "Pollutional Effects of Pulp and Paper Mill Wastes in Puget Sound,"
Dept. of Interior (F.W.Q.A.), Mar. 1967.
15. American Pub. Health Assoc., "Standard Methods for the Examination
of Water and Waste Water." 12th Edit., New York, N.Y. (1965).
36
-------
SECTION IX
GLOSSARY
Agitation - Any external means used to disturb and maintain in
suspension sediment material.
Benthic - Refers to that sediment material found on the bottom of rivers,
lakes, and estuaries.
Biochemical Oxygen Demand (B..O..D.) - The amount of dissolved molecular
oxygen required to satisfy the biochemical reactions involved in the biochmical
breakdown of organic material, mg/Jl.
Bottom Sediments - see Benthic.
Dilution Salts - A solution mixture of phosphate buffer, magnesium sulfate,
calcium chloride and ferric chloride used to insure buffering capacity and
the presence of necessary trace elements during the biological decomposition
of organic compounds.
dy_ - The initial oxygen uptake rate mg/A/hr.
dto
It - First order rate constant, hr
L - The ultimate oxygen demand attributed to the first order biochemical
reactions which occur during the decomposition of organic compounds, mg/£.
Microbial Respiration - That biological oxidation process in which molecular
oxygen is used as the oxidizing agent.
Nitrification - The conversion of ammonia to nitrate.
Oxygen Demand - see Biochemical Oxygen Demand .
Reaction Vessel - That component of the Warburg apparatus in which the
biochemical reactions occur.
Resuspended Bottom Sediments - Refers to that normally quiescent bottom
material that has been disturbed and placed in suspension as a result of
agitation.
Seeding - The process of introducing external microorganisms into organic
solutions to enhance the presence of biochemical reactions.
Sludge - see Bottom sediments.
37
-------
_t - Elapsed time in hours.
Total Volatile Solids - That amount of the total solids which will ignite
at 600°C.
Warburg Cam - Mechanical component of the Warburg appratus which can be
used to vary the severity of agitation experienced by the reaction vessel.
Warburg Respirometer - A mechanical instrument that can be used to measure
microbial respiration.
£ - The amount of oxygen consumed due to microbial respiration, mg/R,.
38
-------
i Accession Number
r. Subject Fu
02K
c Organization
Id &, Group
SELECTED WATER RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
Wachinnt.nn. Denartment of Civil Encrineerina
Title
THE OXYGEN UPTAKE DEMAND OF RESUSPENDED BOTTOM SEDIMENTS.
10
Authors)
Berg, R. H.
16
21
Project Designation
16070DCD09/70
Note
Contract 14-12-481
22
Citation
Water Pollution Control Research Series 16070DCD09/70, 34 p.
23
Descriptors (Starred First)
*biochemical oxygen demand
sludge
estuaries
dissolved oxygen
sediments
25
Identifiers (Starred First)
*Warburg respirometer
Bellingham Bay
benthic sludge
27
*bstract A laboratory study has been conducted to show the application of the Warburg
respirometer in evaluating the influence of light, sodium chloride, chlution saIts,
temperature and agitation on the maximum oxygen uptake rate of disturbed bottom sedi-
ments. Experiments were conducted on estuarian benthic material obtained from
in a., experiments the initial oxygen uptake rate was the maximum "P^e rate
Results obtained using distilled Water as the suspending medium were not Appreciably
altered due to the addition of BOD dilution salts, or sodium jjloride in concentrations
less than 30,000 mg/1. The initial uptake rate also appears to be insensitive to light.
Ambient temperatures were varied from 10°C to 20°C and agitation Bettings were
varied from instrument maximum to twenty-five percent of maximum. .*/2xv^er hour
samole showed variations in initial uptake from 2,000 to 57,000 mg/1 of oxygen per hour.
TheWhalcom Crelk sample had a range of from 2^00 to 83,000 mg/11 of oxygen per hour.
Results indicate that the maximum uptake rate is very sensitive to temperature,
degree of disturbance, and the total volatile solids concentration of the benthic
materAgiiation alone was shown to account for at least a ten fold increase in the maximum
oxygen dema
IJTT HUT1"!! '.-1lrT
Abstractor p
T
H,
ffi-1fii
'P' '«'
Berg
syfem
itted.in ful
v Qffirp ana
Institution
fillment
Seattle
Seattle
fif. Project
GmverSitv
University
16070DCD, Contract
, Washington
No.
14-12-481,
WR:102 (REV. JULY 1968)
WRSIC
US DEPARTMENT OF THE INTERIOR
WASHINGTON. D. C. 20240
* GPo: 1969-359-339
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|