-------
TABLE 10
VOLATILE ACID AND SPECIFIC ORGANIC PROFILES
IN OPERATING PACKED COLUMNS
Feed(a)
6" from inlet
15" from inlet
(r)
Effluentv '
Methyl
Isobutyl
Ketone,
mg/1
132
19
5
nil
Crotonaldehyde,
mg/1
525
nil
nil
nil
Volatile Acids,
mg/1 as HAc
570
325
nil
nil
Feed(b)
6" from inlet
15" from inlet
Effluent
600
176
nil
nil
(a)
(b)
(c)
Unit receiving mixed degradable feed plus crotonaldehyde
Unit receiving volatile acid feed
Both columns are 30 inches total height
69
-------
During the second study, a combination of four inhibitors
(formaldehyde, ethyl acrylate, phenol, and acrylonitrile)
was slowly introduced to a column to the point of
complete inhibition (as measured by reduction COD
removal and gas production); the effluent from this
column was fed to another column for possible further
treatment.
The final phase utilized the performance of the control
observed in the first studies as compared to the
performance in treatment of two process unit waste
streams from one of Union Carbide Corporation's
petrochemical manufacturing facilities. These wastes
were introduced over a period of time to allow
acclimation to inhibitory materials known to be
present.
Packed-Bed Results
The control unit receiving the Synthetic Feed "B"
provided a baseline removal of 90 to 98 percent of
the applied COD while operating at a temperature
of 35°C, a detention time of 1.5 days, and a
volumetric loading of 110 to 130 Ib COD/1000 ft3-day.
Gas production for this unit ranged from 1.5 to
2 liters/day.
Crotonaldehyde Unit - Performance of the packed column
receiving the synthetic plus crotonaldehyde. both
under steady operating conditions and during failure
are illustrated in Figure 32. The unit had success-
fully received up to 500 mg/1 of crotonaldehyde in
gradually increasing (over 132 days) dosage with no
adverse effects. During this time the COD reduction
was comparable to that observed in the control unit
and gas production was in excess of that in the
control, both indicating degradation of the croton-
aldehyde .
Preliminary operational problems developed on Day 140
after two days of 700 mg/1 crotonaldehyde feed. A
drop in both gas production and COD removal was noted
at this time, and subsequent chromatographic analysis
indicated considerable leakage of crotonaldehyde
in the effluent. After the influent concentration
was increased to 800 mg/1 a complete failure of the
unit was observed. The effluent pH remained within
70
-------
FIGURE 32
EFFECT OF CROTONALDEHTOE ON PERFORMANCE OF PACKED-BED
ANAEROBIC TREATMENT UNIT
9.0
o. 8.0
u
I 7.0
C
y-i
" 6.0
s n
"
/
/
— • — o
A,
>)_
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^1
eh-
(
^
^v 1
v
\/
" Addttior
added
_^-<^
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^r
al buffer
j
124
132 136 1AO 144
Operating Time, days
71
148
152
-------
the desired range until about five days after the first
problem indication, at which time additional buffer was
required. The five-day lag indicates that the pH level
was not a contributing factor in the unit upset.
The crotonaldehyde concentrations treated in this study
are considerably greater than those at which inhibition
was noted in both the substrate limiting (200 mg/1) and
non-substrate limiting (150 to 200 mg/1) unacclimated
Warburg experiments. Although the upper limit of an
acclimated system in Warburg experiments was not
determined, the 600 mg/1 concentration which was
effectively treated was considerably greater than that
tested in the acclimated equipment and should yield
an effective upper limit for an acclimated system.
Effect of Combined Inhibitors
An examination of the effects of combined inhibitors
was made in a packed column in which four known
inhibitors (formaldehyde, ethyl acrylate, phenol and
acrylonitrile) were introduced in slowly increasing
quantities (equal concentration of each) spiked into
the degradable synthetic organic substrate. In the
latter part of the study after the column was inhibited
severely in gas production and COD removal but was
still producing volatile acids, the effluent was
treated in another column to determine the efficiency
of the packed column as a pretreatment, detoxifying
device.
Data obtained during the period of increasing concen-
tration of inhibitory materials and subsequent failure
of the column are presented in Figure 33 while data
on both the first and second of the series units are
presented in Table 11. System performance was inhibited
initially at 7.5 mg/1 dosage of each material but
subsequently recovered. Increasing the concentration
to 25 mg/1 of each material resulted in a complete
cessation of gas production and essentially no COD
removal. The acid-forming segment of the population
was still active as evidenced by the buildup in
effluent volatile-acid concentration. During the period
of time that a 25 mg/1 inhibitor concentration or
less was applied to the first of the series units,
the second unit was able to perform well on the
effluent yielding a 70 percent COD removal and above
72
-------
40
30
| - 20
O tt>
u
o
.0
f4
c
10 .
100
FIGURE 33
EFFECT OF FOUR INHIBITORS ON PERFORMANCE OF
PACKED-BED ANAEROBIC TREATMENT UNIT
(ladi
_ -T^
vidual Conor
. x 4 - 160
mg/D-
25
50
75
Time, days
100
125
150
150
73
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in the second reactor and an 88 percent removal in both
reactors As the concentration of each inhibitor was
raised to 40 mg/1 the second column was inhibited. The
acid-forming culture in the primary column was also
inhibited as evidenced by the decrease in effluent
volatile-acid concentration. An active volatile-acid-
forming culture would be necessary to alter the toxic
materials and prevent leakage of inhibitory materials
into the effluent.
Examination of the inhibitory concentration of each of
the four materials (Table 7 ) indicates that at the
40 mg/1 feed concentration formaldehyde was near the
inhibitory dosage while the ethyl acrylate, acrylonitrile,
and phenol was well below inhibitory levels for the
individual material. The severe nature of the
inhibition observed at this concentration indicates
that toxicity may be due to a cumulative effect of
the four materials.
Data collected from chromatographic examination of
the effluent of the two series columns on Day 125 are
presented in Table 12. During this time period the
second series column failed, The first column shows
virtually no alteration of the applied phenol or
formaldehyde, which allowed these materials to pass
through and inhibit the second unit. In summary,
the series operational system was found to be an
effective treatment scheme for the mixed inhibitors
at low concentrations, but failed with the penetration
of inhibitors at higher dosage levels. The mixed
inhibitors were indicated to act synergistically
since they were more detrimental to unit performance
as a mixture than would have been predicted based
on individual chemical inhibition tests.
In order to apply the results of this study, two actual
waste streams from one of Union Carbide's synthetic
organic chemical plants were treated in anaerobic
packed-bed reactors. These streams contained materials
which were identified as inhibitory in screening
studies or were detrimental to aerobic treatment.
The two streams used in testing were selected so
that neither associated cations nor contained
sulfates would cause toxicity problems, which might
complicate interpretation of any inhibition due to
organic constituents. In addition, wastes selected
75
-------
TABLE 12
CHROMATOGRAPHIC EXAMINATION OF SERIES PACKED COLUMNS
TREATING MIXED INHIBITORS
Compound Concentration, mg/1
Feed to first
series column
First-column
effluent
Second-column
effluent
Ethyl
Formaldehyde Acrylonitrile Acrylate Phenol
40
40
40
24
17
40
12
40
37
12
Gas chromatographic analysis employed the following conditions:
Column 6' x 1/8" Porapak P
Column temp.: 80°C for 2.5 min., then programmed at
5°/min to 150°C and 10°/min to 225°C.
Carrier flow: 50 cc/min
Injection port
temp.: 250°C
Detector: Flame ionization
Detector temp: 250°C
76
-------
were of reasonably low flow and high carbon concentra-
tion which would make separate anaerobic treatment a more
practical consideration.
The actual waste streams selected for study are described
in Table 13. The streams were modified as described below
prior to feeding to the packed-bed reactors. Waste C
was diluted with eight volumes of tap water to 1) provide
an equivalent COD loading to previous studies, 2) to
dilute known or suspected inhibitors (crotonaldehyde
and acetaldehyde in particular), and 3) to yield a
reasonable volatile acid level in the feed. Unit D
waste was increased in strength by adding 50 percent
by volume of the following mixture:
Acrylic acid - 270 mg/1
Acetic acid - 2430
Acetone - 405
Acetaldehyde - 135
Isobutanol - 270
Isopropanol - 270
TERGITOL Surfactant NPX - dosage increased
during course of experiment
The additives were used to compensate for dilute waste
content in samples collected from the operating unit
during the studies and to provide a reasonable COD
loading.
Experiments treating actual waste streams were conducted
in a manner similar to those with crotonaldehyde as
previously cited. The reactor was first seeded with
domestic anaerobic sludge and the degradable supplemental
feed used to achieve a suitable culture capable of
90 to 98 percent COD reduction. The waste in question
was then introduced slowly until it reached 100 percent
of the reactor feed.
Unit C - Data obtained while treating the inhibitory
waste are summarized in Figure 34 and Table 14.
Introduction of the wastewater resulted in a reduction
of performance from the 90 to 98 percent obtained
with degradable Waste B to an equilibrium level of
68 percent when treating 100 percent of the diluted
unit feed. A period of inhibition was initially
noted at 60 percent feed strength, but continued
feeding at this level resulted in a resumption of
satisfactory performance, Chromatographic examina-
77
-------
TABLE 13
WASTE STREAMS STUDIED IN ANAEROBIC PACKED COLUMNS
Waste A - Synthetic Volatile Acid Feed Used for Startup
COD - 3000 mg/1
990 mg/1 propionic acid (1500 mg/1 as COD)
1400 mg/1 acetic acid (1500 mg/1 as COD)
pH - 6.2 with sodium hydroxide
Tap water
COD/N/P ratio 100/1/0.2
Waste B - Degradable Mixed Organic Feed
COD - 2800 mg/1
Components
Acetic acid, ethylene glycol, ethanol,
methyl isobutyl ketone, sodium benzoate.
Added on equal COD contribution/compound
pH - 7,0 with sodium hydroxide
Tap water
COD/N/P ratio 100/1/0.2
78
-------
TABLE 13 (CONTINUED)
Waste C - Inhibitory Waste
Total Carbon - 10,000 rag/1
COD - 25,000 rag/1
Na and Ca content - 400-800 mg/1
Sulfate - 20 rag/1
Identified major constituents and order-of-magnitude con-
centrations, rag/1
Butanol 200 mg/1
Ethanol 200
Acetic Acid 2500
Butyric acid 300
Acetaldehyde 700
Crotonaldehyde 1500
Waste D - Surfactant-Containing Waste
Total Carbon - 800-1500 mg/1
Na and Ca content - 1000-2000 mg/1
Sulfate - 55 mg/1
Identified major constituents and order-of-magnitude con-
centrations
Isobutanol - 60 mg/1 Crotonaldehyde- 10
Ethanol - 5 Acetone - 5
Acetic acid - 10 mg/1 Benzene - 50
Acrylic acid - 10 mg/1 Methyl ethyl pyridine - 10
Acetaldehyde - 10 Isobutyl acrylate - 20
Surfactant concentration -
10-15 mg/1
79
-------
FIGURE 34
PERFOFMANCE OF ANAEROBIC PACKED COLUMN
TREATING INHIBITORY WASTEWATER
UNIT C
1UU
H
*
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5! 75
[*
a
2 »
to
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25
0
0
-
-
r^
J
60 120 180 240 30
Period of Teat, days
300
TZD ISO
Period of Test, days
2.5
120 180
Period of Test, days
240
300
80
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tion of the column effluent on Day 227 when the reactor
was receiving 60 percent inhibitory feed indicated that
the reduction in COD efficiency was caused by leakage
of acetaldehyde contained in the waste and methyl
isobutyl ketone contained in the supplemental feed.
Unit D - Data obtained while treating the surfactant-
containing waste are presented in Table 15 and Figure 35,
The waste was treated fairly well in terms of COD
removal at 100 percent of the feed, although a decrease
in COD removal from greater than 90 percent to
65 percent was noted above 80 percent (by volume) actual
wastewater in the feed. Treatment of this unit waste
was of particular interest due to contained "hard"
surfactants which caused foaming problems and are
not degraded in aerobic systems. If not degraded, these
surfactants could be expected to cause similar
problems in mixed anaerobic systems, particularly in a
system employing organism separation and recycle.
Surfactant measurements (cobalt-thiocyanate-active-
surfactant measurements, Appendix I) indicated that
the "hard" surfactants were not detected in the
effluent from the anaerobic reactor at waste concen-
trations of 45 mg/1 and below. The analysis is a
measurement of surfactant remaining in its original
form, since a color complex is formed with oxide chains
of six or more units. Supplementary foaming experiments
(Appendix I) indicated that the removal of greater
than 90 percent surfactant level was accompanied by a
decrease in foamabillty of at least 50 percent.
Foamability data would be conservative since many
biological systems have a tendency to produce foam.
Supplemental surfactant added to the unit waste up
to a concentration of 160 mg/1 resulted in a break-
through of material measurable by the cobalt-
thiocyanate method as indicated in Figure 35.
Once the surfactant began to appear in the
effluent there was essentially no decrease in
foamability.
Discussion of Acclimation Achieved
The conservative nature of the estimates of inhibitory
concentrations defined during initial Warburg studies
with unacclimated biomass was emphasized by the results
of anaerobic bacterial acclimation studies. In many
82
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TABLE i?
PHOTOSYNTHETIC BACTERIAL GROWTH ON PURE CHEMICAL SUBSTRATES
Seed Oroanic Chemical V1) Result^'
GSB(a) Distil led water
GSB Acetic acid
GSB Ethanol
GSB Ethylene glycol
GSB Methanol
GSB Acetone
GSB Methyl ethyl ketone
GSB Acetaldehyde
GSB Sodium benzoate
PSB^) Distilled water
PSB Acetic acid
PSB Ethanol
PSB Ethylene glycol
PSB Methanol
PSB Acetone
PSB Methyl ethyl ketone
PSB Acetaldehyde
PSB Sodium benzoate
PSB(c) Distilled water
MOd) Distil led water
(a) Predominately green sulfur bacteria
(b) Predominately purple sulfur bacteria
(c) Predominately purple sulfur bacteria
(d) Mixed culture
(e) 1 ml feed stock of each named
Red (R) and Green (G)
R
R
R
G
R
White (W)
R
W
G
G, R, Brown (B)
G
G&R
G
G &R
G
G &R
G
G
G
from laboratory lagoon
from Texas Plant lagoon
from another Texas lagoon
Finol pH
7.6
6.98
8.5
7.3
7.65
7.22
8.65
7.4
8.4
8.38
7.0
7.38
7.4
8.02
7.5
8.5
7.8
8.2
8.0
8.0
(f) After 25 days incubation in mixed incandescent-fluorescent light
NOTE: The media used was that of Skerman for growth of Chromotlum; Skerman, V. D. B.
Genera of Bacteria, Williams AWilkins Co., Baltimore, Md., 1967.
90
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Chlorobium chlorophyll while the red growth had those
characteristics of Chromatium species. Attempts
were made to seed with purple sulfur bacteria from
a waste treatment lagoon at Union Carbide's Texas
City Plant. After approximately two months of
operation the green sulfur bacteria containing
Chlorobium chlorophyll became the predominant
population. Attempts made to swing population
predominance to purple sulfur bacteria by pH
adjustment and by increasing feed stock concentration
were unsuccessful, so the less common green
sulfur bacteria of the family Chlorobacteriaceae
were used in these studies rather than the
Thiorhodaceae identified in the lagoons under
Grant 12020-DIS.
In an attempt to determine whether some component
in the feed was limiting growth, an experiment
was designed to test growth of the red and green
sulfur forms on various pure chemical substrates.
Results are included in Table 17. Results are not
conclusive but indicate that both green and purple
sulfur bacteria can grow on the media utilized in
the presence of acetic acid, ethanol, ethylene
glycol, acetone and acetaldehyde. The purple
sulfur bacteria were not observed to grow in the
presence of methanol, methyl ethyl ketone, or
sodium benzoate in this test. It is to be under-
stood that although the photosynthetic bacteria
can grow, they do not necessarily oxidize sulfides.
This work was not continued due to the limited
scope of the sponsoring project and lack of pure
photosynthetic bacterial cultures. It could act
as a starting point for other work testing inhibition
of organic chemicals on lagoon ecology.
In the face of changing photosynthetic cultures
the units provided approximately equal removal of
applied COD during the initial period. COD removals
during the length of the experiment are given in
Table 18.
Experiments were also conducted during the initial
period to measure diurnal changes in parameters
expected to vary in a situation of bacterial photo-
synthesis. Measurements of pH at the end of the
dark period and at the end of the light period during
89
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TABLE 16
ANAEROBIC LAGOON FEED
(a )
Feed Concentration, Equivalent TOD,
mg/1 mg/1
Acetic acid 400 428
Ethanol 100 210
Ethylene glycol 200 260
Methanol 75 112
Acetone 100 220
MEK 20 50
Acetaldehyde 40 58
Sodium benzoate 20 32
Sulfate 200 (initially)
1370(b)
NOTE: (a) TOD based on theoretical oxidation of all carbon
to CO2 and all hydrogen to H2O
(b) Actual COD 1230, Ratio of COD/TOD = 90%
The feed was made up as a concentrate and added
to 20 liters of distilled water which was sufficient
to last approximately 5 days. A more concentrated
feed was made by adding more of the concentrate to the
dilution water. Buffer-nutrient was described previously
88
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FIGURE 36
ANAEROBIC LAGOON
Light Source
25 watt Incandescent
40 watt Fluorescent
Wet Test Meter
— Vent
Effluent
Sampling Porh
Mixed Lev/-Solids
Supernatant
Heavy Domestic Sludge
Recycle Mixing
rXimp
87
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oxidation of produced sulfides, This oxidation would
provide a means of off-setting toxicity of sulfides
produced in anaerobic treatment of high sulfate wastes
as well as yield additional capacity for reduction
of oxygen-demanding wastes through re-oxidation of
sulfides to sulfates and by providing an additional
bacterial culture which could oxidize organic wastes.
The experimental apparatus described as follows was
assembled and seeded in an effort to reproduce
average feed and environmental conditions observed
in the previous experimental work.
Ex pe r i m e n t a 1 Ajjp a r a_t, us a n d__Proc e dur e for J5u 1 f jl de Study
The Laboratory lagoons consisted of two identical
units as illustrated in Figure 36. The containers
were constructed from glass battery jars while the
tops were of plate glass, which was selected to
allow passage of Light wavelengths desirable to
sulfur bacteria „ Continuous feed of the mixed
chemical feed indicated in Table 16 was provided
in order to treat a representative waste and to
develop an acclimated sludge. Continuous mixing
was provided via a recycle pump while an incandescent-
fluorescent mixed light source was connected in
series with a timer to allow any light-dark ratio
desired. Gas produced was measured using a wet test
meter and was sampled using a hypodermic syringe.
The units were initially seeded to a depth of 3 inches
with a 23 percent, solids domestic primary sludge
from the St. Albans, West Virginia wastewater
treatment facility. Hydraulic retention time
was set at 15 days. Samples from each unit
were taken each working day and were analyzed
daily for pH and periodically for COD, volatile
acids, alkalinity, sulfides, sulfates and ORP,
Daily gas production measurements were made.
ts of ___Sulf_ide _J3tudy
During the startup period both units were operated
on a 12-hr, light-dark cycle, During this
period, the suspended culture within the units
swung from a green to a red predominant coloration.
At times, one unit would be red, while the other
was green. Light absorption spectra indicated the
green growth had the predominant peaks for
86
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cases compounds which were inhibitory in unacclimated
Warburg studies were found treatable or able to be
tolerated in considerably greater concentrations
after acclimation,
Successful acclimation was found to take two general
courses. In the case of crotonaldehyde and ethyl
acrylate the compound was found to be degraded by
chroma tographic analysis when acclimation was success-
ful,, It is conceivable that the compound per se_
could still be inhibitory but was degraded at a great
enough rate so that sufficient concentrations were not
reached for inhibition. In the case of phenol no
decomposition of the material was observed in the
anaerobic system, however, higher concentrations
were tolerated after acclimation. While acclimation
was successful for some single inhibitors, a more
difficult problem exists with mixed inhibitor systems
which may produce synergistic effects.
Acclimation was found to be unsuccessful in a digester
type reactor unless complete mixing was provided.
No such problem was observed in the packed bed type
reactor .
Acclimation in anaerobic systems was at best a slow
process. Considerable difficulty would likely be
experienced in startup of a full-scale process treating
an inhibitory waste.
Inhibition due to sulfides in anaerobic treatment of
petrochemical wastes was studied due to the presence
of sulfate ions in many petrochemical waste streams.
The sulfate ions within the stream are reduced,
which produces hydrogen sulfide, that can cause
toxicity (16), odor, and corrosion problems.
Under the related EPA Grant 1202Q-DIS, "Anaerobic
Treatment of Synthetic Organic Wastes," an open
lagoon with a photosynthetic , sulfur-oxidizing
bacterial culture was found to be effective in
controlling sulfide concentrations.
In this study laboratory-scale lagoons were designed
to quantify under controlled conditions of feed,
temperature, and sunlight, the photosynthetic
85
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FIGURE 35
PERFORMANCE OF ANAEROBIC PACKED COLUMN
TREATING SURFACTANT CONTAINING WASTEWATER
0
100,-
100 200 300
Period of Test, days
400
2.5
100 200 300
Period of Test, days
400
250
100 200 300
Period of Test, days
400
84
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D| 3
-------
one day indicated no change during the photo period
(4/6 and 4/7/70). Measurements of sulfates and sulfides
under the same conditions at a later date also indicated
no change from day-night values (6/17/70) under the
low levels of feed sulfate tested.
After essentially identical performance had been
established in the two units, Unit B was covered
with black polyethylene while Unit A was subjected
to conditions of continuous light. The units were
then operated at the initial 200 mg/1 feed sulfate
level while increasing the concentration of organic
in the feed to determine differences in sulfur
transformation in the light-dark cases under
varying conditions of organic loading. As indicated
in Table 18, while the feed concentration was raised
to three times the original level no significant
differences were observed in measured sulfide levels, also
in neither unit was the sulfate concentration depleted
completely as would be expected in an anaerobic
environment. The increased feed brought the units
almost to failure as measured by pH and volatile
acid levels. Feed was, therefore, terminated for a
period of two weeks and was resumed for the remainder
of the experiment at a level of 1.5 times that given
in Table 16.
The final state of experimentation was a rapid increase
in sulfate feed concentration to unit failure. As
evidenced in the plot of sulfur compounds versus
time (Figure 37), the sulfates became a problem
at a level between 1500 and 3000 mg/1. Sulfates were
not quantitatively reduced to sulfides but lagged
well behind the equivalent level of applied sulfates.
During the period of initial operation approximately
75 percent of the applied sulfates were present in
the mixed reactor as sulfides. Both the light and
dark reactors experienced approximately the same
level. The lighted system apparently maintained
a greater level of bacterial activity and, hence,
a more rapid conversion was evidenced during the
final sulfate feed acceleration. The dark unit
provided a much lower overall sulfide level. If
photosynthetic oxidation were the controlling
mechanism limiting sulfide level, the results would
be reversed - that is, the light unit would have the
lower sulfide level.
92
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93
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When the sulfide level within the lighted lagoon
reached the 140 to 170 mg/1 sulfide-ion level, the
COD reduction within the unit rapidly dropped.
Attempts were made to revive the system by decreasing
organic feed levels with no success, The dark unit
maintained a satisfactory level of reduction during
this period. Strangely, the conventional parameter
of pH did not forecast the unit failure as pH was
satisfactory at all times. Possibly inhibition was
total rather than selective for methane bacteria
at the level observed. The observed level of
sulfide at which inhibition occurred was slightly
below the 200 mg/1 soluble sulfides quoted as
inhibitory by Lawrence, McCarty, and Guerin (16).
Purple sulfur bacteria reportedly (17, 18) are
inhibited in their utilization of sulfides by
presence of a more readily degradable feed such as
acetate. The observed extent of this sparing action
varies with the reporting investigator. Apparently
a similar phenomena exists with the green sulfur
group containing Chlorobium chlorophyll. The unit
providing a light source for photosynthetic growth
did not at any time exhibit significant evidence
of sulfide oxidation in diurnal measurements or in
comparison with an unlighted unit.
The lack of photosynthetic sulfur oxidation observed
in these studies was in direct contrast to the high
degree of oxidation previously reported in pilot-
scale anaerobic facilities treating similar wastes (10)
One immediately obvious difference between the
experimental systems was the predominant bacterial
groups present - Thiorhodaceae when oxidation was
observed and Chlorobacteriaceae when no oxidation
was observed. Some fundamental research beyond
the scope of this project on environmental conditions
for growth and inhibition would be required to
document the cause for the change in predominance
between the two systems.
94
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SECTION VI
ACKNOWLEDGMENTS
This project was completed by the Research and
Development Department of Union Carbide Corporation,
Chemicals and Plastics Division, under
the general supervision of Mr. R. A. Conway
and the immediate direction of Mr. J. C. Hovious.
Mr. J. F. Dietrich and Mr. G. T. Waggy conducted
most of the laboratory studies and Mr. Waggy
shared the reporting responsibilities with
Mr. Hovious.
The contributions of Messrs. J. W. Ferguson (Project
Officer), J. A. Horn and Ray George of EPA are
gratefully acknowledged.
Dr. P. L. McCarty of Stanford University and
Dr. J. Vennes of the University of North Dakota
contributed valuable technical assistance as
consultants.
95
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SECTION VII
REFERENCES
1. Fisher, J. A., Hovious, J. C., Kumke, G. W., and
Conway, R. A., Water - 1970, AIChE Chemical
Engineering Process Symposium Series, 67, 107
(1971).
2. Hovious, J. C., Conway, R. A., and Harvey, Z. B.,
"Pilot Studies of Biological Alternatives for
Petrochemical Waste Treatment," Presented at
26th Purdue Ind. Waste Conference, May 4-6, 1971.
3. Heukelekian, H., and Rand, M. C., J. Water Pollution
Control Federation, 27, 9, 1040 (1955).
4. Lamb, C. R. and Jenkins, G. F., Proc. 7th Ind. Waste
Conference, Purdue Univ. Ext. Ser. 79, 326 (1952).
5. Stack, V. T., Jr., Industrial and Engineering
Chemistry, 4£, 5, 913 (1957).
6. Hatfield, R., Industrial and Engineering Chemistry,
49_, 2, 192 (195TT
7. Gerhold, R. M. and Malaney, G. W., J. Water
Pollution Control Federation, 38, 4, 562 (1966).
8. Buzzell, J. C., Jr., Thompson, C. H., and
Ryckman, D. W., Behavior of Organic Chemicals
in the Aquatic Environment, Part III - Behavior
in Aerobic Treatment Systems (Activated Sludge),
Manufacturing Chemists Association(1969).
9. McCarty, P. L., Public Works, 95, 10, 123; 11, 91
(1964).
10. Hovious, J. C., Conway, R. A., and Ganze, C. W.,
"Anaerobic Lagoon Pretreatment of Petrochemical
Wastes," Presented at 44th Annual WPCF Convention,
October 3-8, 1971.
11. Umbreit, W. W., Burria, R. H., and Stauffer, J. F.,
Manometric Techniques, Burgess Publishing Company,
Minneapolis, Minnesota, 4th ed. (1964).
97
-------
12. McCarty, P. L., Jeris, J. S., and Murdock, W.,
J. Water Pollution Control Federation, 35, 12,
1501 (1963).
13. Lawrence, A. W. and McCarty, P. L., J. Water
Pollution Control Federation, 41, Rl (1969).
14. Lank, J. C., Jr., and Wallace, A. T., "Effect of
Acrylonitrile on Anaerobic Digestion of Domestic
Sludge," Presented at the Purdue Industrial Waste
Conference, May 1970.
15. Young, J. C. and McCarty, P. L., J. Water Pollution
Control Federation, 4J^ 5, R160 (1969).
16. Lawrence, A. W., McCarty, P. L,, and Guerin, F. J. A.,
Int. Journal Air Water Pollut., 1_0, 207 (1966).
17. Shaposhnika, V. N., Osnitskaya, L. K., and Chudina, V. I.,
Mikrobiologiya, 29, 9 (1960).
18. Vennes, J. W., Personal communication.
19. Standard Methods for the Examination of Water and
Wastewater, 12th ed., Am. Public Health Assoc., Inc.,
New York (1965).
20. Mausner, M., et al., "The Status of Biodegradability
Testing of Nonionic Surfactants," Scientific and
Technical Report No. 6 published by the Soap and
Detergent Association, October 1969.
21. Hovious, J. C., Fisher, J. A., and Conway, R. A.,
"Anaerobic Treatment of Synthetic Organic Wastes,"
Water Pollution Research Series 12020 DIS 01/72,
January 1972.
98
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SECTION VIII
APPENDIX
Analytical Methods
A. Alkalinity - Alkalinity was determined to
the methyl orange end point as given in
Standard Methods (19)
B. Anaerobic Gas Composition - Gas composition
was measured using mass spectrographic
equipment
C. Chemical Oxygen Demand (COD) - COD
determinations were made on filtered
samples by the dichromate-reflux method
as presented in Standard Methods (19)
D. Determination of Polyether Nonionic
Surfactants
Reagents
a. Cobaltous Thiocyanate Reagent:
Dissolve 28 grams of cobaltous
nitrate hexahydrate, Co (1^)3)2'6 H20,
and 62 grams of ammonium thiocyanate
in 85 grams of distilled water. Pre-
extract the reagent with three ten-mi
portions of chloroform.
b. Ethyl Ether: Reagent grade (use
appropriate precautions when handling
ethers)
c. Chloroform: Reagent grade
Procedure
a. To a 250-ml cylinder add 50 ml of
sample and 50 ml of ethyl ether.
b. Via a glass-frit sparging tube, pass
nitrogen thru the aqueous phase,
permitting the bubbles to form in the
aqueous phase before passing into
the ether layer. Allow this sparging
to continue for five minutes.
99
-------
c. Pour the two phases into a separatory
funnel and discard the aqueous
(bottom layer).
d. Place the separatory funnel in a steam
bath and evaporate the ethyl ether (vent)
e. After the ethyl ether is evaporated and
the funnel has cooled, add 2 ml of
cobaltous thiocyanate reagent.
f. Swirl the cobaltous thiocyanate
reagent over the entire surface
of the funnel.
g. Via a pipet, add five ml of chloroform
to the funnel and shake for one minute.
h. Allow the phases to separate, then
draw off enough of the chloroform
layer (thru a glass plug in the funnel
stem) to fill a one-centimeter absorption
cell.
i. A blank is prepared by starting with step
j. Measure the absorbance of 620 mu on
a spectrophotometer (Beckman Model B
or its equivalent) using the blank
to set the instrument zero.
Calculation
Surfactant concentration is calculated based
on standard curves prepared for the individual
surfactants.
E. Soluble Sulfides - Sulfides were monitored
by Orion Research Incorporated selective
ion electrode.
F. pH - pH was measured using the Glass Electrode
Method specified in Standard Methods (19).
100
-------
G. Sulfate - Sulfate ion concentrations were
measured using the Turbidimetric Method
presented in Standard Methods. The analysis
was investigated, and no interferences were
found in the anaerobic system.
H. Volatile Acids - Volatile acid concentrations
were determined by the Column-Partition
Chromatographic Method presented in Standard
Methods.
I. Total Carbon (TC) - Total carbon measurements
were made on filtered samples using the
Union Carbide Total Carbon Analyzer,
J. Foam - Foam measurements across the unit
were made by the following procedure
published by the Soap and Detergent
Association (20), A 50-ml aliquot of the
sample whose foaming ability was to be measured
was placed in a scrupulously cleaned, 100-ml,
glass-stoppered, graduated cylinder. The
cylinder was shaken by hand for 15 seconds
at a rate of 2 to 3 vigorous strokes in a
vertical direction per second. The volume
of foam was visually read from the calibra-
tions on the cylinder after the vessel had
set for 15 seconds and 60 seconds. The foam
volume was read in milliliters and reported
as "ml of foam per 50 ml of solution."
A foam reading of zero was reserved for the
condition of absolutely no foam. When
the surface of the test solution was only
partially covered with foam, such as by
a ring of small bubbles around the periphery
of the graduate, a special measuring
technique was used. The volume of foam was
estimated to the nearest 0.1 ml by viewing
from above and comparing to a standard set of
diagrams. The cylinders used were thoroughly
cleaned and rinsed prior to and between
foam measurements. The precision of
foam measurements was improved significantly
by having all determinations in a series
of tests performed by the same person.
101
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Experimental Procedures
Intermittently Mixed Digesters (Test Series #1) - The
technique used in Test Series #1 utilized ten one-quart
bottles as reactors, which allowed for duplicate test
units for three chemicals and two biomass controls
(one set of controls being fed calcium acetate). A
typical bottle charge consisted of 300 ml of screened
seed sludge from an anaerobic digester at a domestic
wastewater treatment plant, 0.5 ml of a buffer/nutrient
solution (21), 3 ml of calcium acetate solution to provide
approximately 300 mg/1 COD and the balance of the
liter made up with tap water and test chemical
dosage. Only 900 ml of this mixture were charged
to the bottle as 100 ml were retained for analysis.
The reactors were placed in a 35°C bath and attached
to a water-displacement gas measuring system.
The reactors were manually agitated twice daily and
gas production was recorded daily. Periodic unit
sampling was accomplished by withdrawing 30 ml of the
supernatant by attaching a 50-ml syringe to the
surgical tubing on the sample tube and releasing
the screw clamp. Gas readings were recorded before
and after sampling in order to correct for any volume
changes. Refeeding of the unit was achieved in much
the same way by diluting 3 ml of acetate solution,
0.1 ml of the buffer/nutrient and the desired test
chemical dosage to 30 ml in distilled water and
injecting the mixture into the sample tube by syringe
and then resealing the system. Although refeeding
was initially set up on a regular schedule, unit
activity or gas production ultimately controlled
the periodic refeeding and the rate of increases
in the test chemical dosages. During periods of
reduced gas production, the test chemical feeding
was held off to allow the system to recover.
Continuously Mixed Digesters (Test Series #2) -
Subsequent acclimation test series were based on
larger-volume, completely mixed reactors. Large
magnetic mixers were used to supply constant
agitation in the four half-gallon bottles utilized
as reactors. The bottle charge consisted of the
following:
102
-------
995 ml tap water
500 ml screened domestic primary digester
sludge
1 ml phosphate buffer-ammonium chloride
nutrient solution (COD/N/P ratio of 100/6/2)
4.5 ml calcium acetate solution
(10 percent acetate-ion content)
The charged reactors were placed in a 35°C constant
temperature bath and connected by rubber tubing to
the inverted-graduate gas collection system. The
water displacement bath was maintained at a pH of
4 to minimize carbon dioxide solubility. Since
no pH problems were evident in the initial test
series, the sampling procedure was eliminated from
this study in an effort to reduce the possibility
of oxygen contamination of the reactors. Refeeding
procedures were the same as in the initial series,
except that the volume of feed was reduced to avoid
over-filling the reactor since no effluent was
taken. Usually the acetate solution, test chemical,
and buffer system was less than 10 ml total volume.
Mixing of this feed out of the addition tube and
into the reactor was obtained by pumping the syringe
after the addition.
103
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SELECTED WATER
RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
1. Report No.
3. Accession No.
w
4. Title Identification and Control of
Petrochemical Pollutants Inhibitory to
Anaerobic Processes
7. Author(s)
Hovious, J. C., Waggy, G. T., Conway, R. A.
5. Report Date 1/73
6.
8. Performing Organization
Report If o.
10. Project No.
12020-FER
11. Contract/Grant No.
13. Type of Report and ,
9. Organization
Union Carbide Corporation, Chemicals and Plastics
Division, Research and Development Department,
South Charleston, West Virginia
12. Sponsoring Organization Ett^Jk3PCHMiental PTOt«e%tttll ;AgeQcy, OfflCS cl1; ItattMUhdU '&VL
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Environment -.1 " ; • L„ •-1 1on Agency
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