TECHNICAL ASSISTANCE PROJECT
AT TIE
ALBANY FETROPOLITAN WASTEWATER TREATMENT PLANT
ALBANY, GEORGIA
Environmental Protect ion Agency
Region XV
Surveillance and Analysis Division
Athens, Georgia
-------
TECHNICAL ASSISTANCE PROJECT
AT THE
ALBANY METROPOLITAN WASTEWATER TREATMENT PLANT
ALBANY, GEORGIA
April 1976
„r,!»av
U v'
Environmental Protection Agency
Region IV
Surveillance and Analysis Division
Athens, Georgia
-------
TABLE OF CONTENTS
Page
INTRODUCTION 1
SUMMARY 2
RECOMMENDATIONS 3
TREATMENT FACILITY 5
TREATMENT PROCESSES 5-
PERSONNEL 7
STUDY RESULTS AND OBSERVATIONS 8
PLOW 8
WASTE CHARACTERISTICS AND REMOVAL EFFICIENCIES 8
AERATION BASINS ' 12
EXAMINATION OF MICROSCOPIC ORGANISMS 15
OXYGEN UPTAKE RATES 17
C'LARIFIERS 18
DISINFECTION 20
SLUDGE HANDLING 21
LABORATORY 21
REFERENCES - 23
APPENDICES
A. CHEMICAL LABORATORY DATA 24
B. DISSOLVED OX1/GEN PROFILES 31
C. GENERAL STUDY METHODS . . . 33
D. ACTIVATED SLUDGE FORMULAE FOR GENERAL CALCULATIONS . . 35
E. OXYGEN UPTAKE PROCEDURE 37
F. DESIGN DATA 39
LIST OF FIGURES
1. ALBANY METROPOLITAN WTP 6
2. WASTEWATER AND RETURN SLUDGE FLOW . 9
3. SPECIAL COD ANALYSIS - ALBANY, GA WTP 11
4. MLSS SETTLEABILITY 14
5.- POPULATION DYNAMICS IN AEROBIC WTP's ' 16
6. CLARIFIER DYE TRACER STUDY 19
LIST OF TABLES
I. WASTE CHARACTERISTICS AND REMOVAL EFFICIENCIES 10
II. OBSERVED AND RECOMMENDED PARAMETERS FOR THE MODIFIED
CONVENTIONAL ACTIVATED SLUDCE PROCESS 12
III. DO CONCENTRATIONS AT
SELECTED STATIONS 15
IV. OXYGEN UPTAKE RATES 18
V. OBSERVED AND RECOMMENDED PARAMETERS FOR
SECONDARY CLAIUFJERS 20
-------
INTRODUCTION
A technical assistance study of operation and maintenance problems
at the Albany Metropolitan Wastewater Treatment Plant (WTP), Albany,
Georgia was conducted March 29 - April 2, 1976 by the Region IV, Surveillance
and Analysis Division, U. S. Environmental Protection Agency. Operation
and maintenance technical assistance studies; are designed to assist waste-
water treatment plant operators in maximizing treatment efficiencies as
well as assisting with special operational problems. Municipal wastewater
treatment plants are selected for technical assistance studies after con-
sultation with state pollution control authorities. Visits are made to
each prospective plant prior to the study to determine if assistance is
desired and if study efforts would be productive.
This plant was selected because of the low BOD^ and solids removal
efficiencies and the sludge bulking problems. The specific study objec-
tives were to:
© Optimize treatment through control testing and recommended opera-
tion and maintenance modifications,
o Introduce and instruct plant personnel in new operational control
techniques,
o Determine influent and effluent wastewater characteristics,
o Assist laboratory personnel with any possible laboratory pro-
cedure problems, and
o Compare design and current loadings.
A follow-up assessment of plant operation and maintenance practices
will be made at a later date. This will be accomplished by utilizing
data generated by plant personnel and, if necessary, subsequent visits
to the facility will be made. The follow-up assessment will determine
if recommendations were successful in improving plant operations and if
further assistance is required. Contact has been maintained with plant
personnel since the study in order to relate preliminary study findings
and stay abreast of process changes and results. Most of the recommenda-
tions in this report have been implemented since the study and recent
reports have shown significant improvements in removal efficiencies.
The cooperation of the Georgia Environmental Protection Division is
gratefully acknowledged. The technical assistance team is especially
appreciative of the cooperation and assistance received from personnel,
of the Albany WTP.
-------
SUMMAKY
The Albany, Georgia Metropolitan Wastewater Treatment Plant (WTP)
was designed to treat 20 mgd of combined industrial, and domestic waste-
waters with a total BOD^ loading of 45,420 lbs. for the project design
year. Currently, the plant is operating at 67 percent of hydraulic
design loading and 113 percent of organic design loading. The heavy
organic loading (avg. influent BOD^ concentration - 460 mg/l) is due
to unregulated industrial discharges. An active industrial monitoring
program plus better in-planL laboratory process control monitoring is
needed, which will require additional field and laboratory staff. Currently,
there is a shortage of qualified operators at the WTP. Plans have been
made and approved by the city to hire additional staff.
The WTP is designed to use the Krauss Process; however, it is
currently being operated in the plug flow mode. For the first time the
plant now seems to be responsive to operator control; and hopefully, wi.thin
a period of months a good, stable operational record can be established.
After it has been established that the WTP can be satisfactorily operated
in the current plug flow mode, start-up of the Krauss Process should be
considered.
Two of the four anaerobic digesters were out of service, causing
severe overloading of the two units in service. Detention time in each
digester was approximately five days. This heavy loading produced highly
acid conditions, poor digestion, and low quality gas production. Parts
for the digesters were on order, and were scheduled for delivery and
installation in May. Poor digestion and the lack of the use of polymer
in centrifuges, resulted in a very poor quality centrate returned to the
aeration (nitrification) basins. This return stream alone required 1/3
of the total aeration capacity of the plant, since two of six aeration
basins were utilized solely for oxidation of the centrate.
During the study, severe bulking conditions were occurring in the
final clarifiers resulting in a large volume of solids discharged in the
effluent. It was observed that a major portion of the aei'ation basin
contents contained very low dissolved oxygen levels, the final clarifiers
were septic and the mixed liquor solids (MLSS) was composed largely of
filamentousvgrowths. Settleability of the MLSS was very poor. The com-
pressed air supply to the aeration basins was stepped up in increments
until adequate DO concentrations existed throughout the basins. The
amount of air required was excessive due to the very young age of the
sludge, excessive filamentous growth, and residual septic conditions.
As the sludge quality improved the air demand decreased. Settleability,
after three weeks of adequate air, exhibitied almost ideal settling
characteristics. This corrected one of the problems; however, severe
carryover of solids still occurred in the clarifiers. This indicated
problems with the sludge collection and return systems.
-2-
-------
RECOMMENDATIONS
Rased on observations and data collected during the study, the
following suggestions are made for improved operations:
1. The dissolved oxygen. (DO) concentrations in the aeration basins
should be monitored and maintained at a minimum of 1.5 mg/1 at
all times. Clarifier DO should also be checked frequently and
aeration basin DO should be sufficient to maintain a residual
DO in the clarifier overflow.and return sludge.
2. An industrial monitoring program should be initiated immediately
to assure compliance with the city sewer ordinance. Excessively
strong wastes are currently being discharged to the system.
3. The return sludge system including pumps, valves, meters, and
vacuum pickup systems should be checked for proper operation.
4. Laboratory control testing and plotting of trend charts should
be performed daily. One individual should then be in charge of
interpreting the data and making decisions on process control
changes.
5. An active program should be developed for recruiting additional
staff and training the existing staff. A one or two hour meeting
and training session each week for operators, laboratory staff,
and supervisors may be useful. These meetings could be used to
train the operating staff in the significance and methods of
control testing. The importance of making visual observations, and
what to look for in clarifier, aeration basins, etc. emphasized.
The meetings would also help to promote better espirit de corps
which is absolutely essential for good operations.
6. Installation should be completed and repairs made to place all
flow measuring devices and recorders in service.
7. The two aeration basins now being used for oxidation of the
centrate should be converted to parallel operation, with the
oth^r four basins, for treatment of raw waste. The quality of
the centrate stream should be improved by the addition of
polymer in the centrifuges and the stream diverted to manhole
//5. The centrate stream may be removed temporarily from the
system by storing" in an on-site lagoon. This flow scheme makes
more efficient use of the plant aeration capacity and eliminates
the uneven flow split into the two nitrification tanks.
-3-
-------
8. The WTP should be operated in the plug flow mode until a good
performance record is established or until information indicates
that this mode will not pr.oduce satisfactory results. Start-up
of the Krnuss process may be advisable at a later date.
9. The intake line for the effluent composite sampler should be
moved to collect a sample from the total plant effluent rather
than from only clarifier it2. Relocation or modification of the
"influent sampler is also needed to prevent clogging.
-------
TREATMENT FACILITY
TREATMENT PROCESSES
A schematic diagram o I; the 20 mgd WTP is presented in Figure 1.
Plant design data arc shown in Appendix F. The WTP was originally designed
in 1955 as a .10 mgd primary treatment facility, and expanded in 1975 to a
20 mgd activated sludge system.
The collected wastewaters are introduced into the treatment facility
by a 54 inch west Slide interceptor sewer, a 36 inch river road interceptor
sewer, and two 20 inch force mains. Wastewaters enter the preliminary
treatment structure containing bar screen and aerated grit chamber, with
flow measurement by two parallel 54 inch Parshall flumes. Chlorine is
applied to the incoming raw wastewaters to freshen the waste and control
odors. Following preliminary treatment, a raw sewage pump station, con-
sisting of eight centrifugal pumps with maximum pumping rates of 60 mgd,
lifts the wastewater to four primary sedimentation tanks. Settled solids
are collected mechanically and pumped to the digesters.
The patented Krauss Process was provided in the addition to the WTP.
This process is designed for nitrogen limiting situations where digester
supernatant nitrogen is oxidized in nitrification tanks and reintroduced
into the aeration basins to support the biological growth. This process
also has the advantage of providing a large volume of well acclimated
activated sludge in the nitrification tanks. The system at Albany con-
sists of six rectangular aeration basins with air diffusers located along
each side of the tanks. The diffusers are located near the bottom on one
side, and near the midpoint on the other side, which produces a rolling
countercurrent circulation in the tanks. Currently, two of the six tanks
are used for nitrification of the digester centrate.
Four circular Rex clarifiers follow the aeration basins. The clari-
fiers are center feed with a single unitube sludge vacuum pickup system.
Each clarifier has a single peripheral overflow weir.
After final clarification, wastewaters flow to the chlorination
facilities. The chlorine application rate is controlled by the flow rate
over the 40 vfoot effluent weir. The outfall line was constructed to pro-
vide a 30 minute contact time, at a flow of 20 mgd.
Thickened primary and waste activated sludge is pumped to four
anaerobic digesters (two out of service for repairs). Supernatant was
returned to the head end of the aeration basins via manhole //5. Digested
sludge is processed in three centrifuges, with the centrate returned to
the nitrification tanks and the solids hauled to a landfill.
-5-
-------
FIGURE I
ALBANY METROPOLITAN WTP
O'.lKrLO* i BYPASS STRUCTURE
>
I
CTv
I
70
S-.MT
LA Ml."
EXISTING STRUCTURES
vnw STRICTURES
-------
PERSONNEL
The City of Albany employs a wastewater treatment staff of 28 persons.
At the time of the study, there were eight certified operators—seven at
the Albany plant and one at the Naval Air Station wastewater treatment
facility. A shortage of qualified operators and full time laboratory staff
exists. Additional laboratory staff will be required if plant operational
control testing and industrial discharge monitoring functions arc adequately
performed.
-7-
-------
STUDY RESULTS AND OBSERVATIONS
A complete listing of all analytical data and study methods are
presented in Appendices A, 13, and C. Formulae used for general calcula-
tions are enumerated in Appendix D. S Lgnf ic.a;.ii; results and observations
made during the study are discussed in the following sections.
FLOW
Due to operational problems with the level recorder on the influent
Parshall flumes, influent flow records are not reliable. Better flow
data was obtained by installing a recorder on the forty foot sharp crested
effLuent weir. The sensitivity (head to discharge relationship) of this
weir could be greatly improved by blocking off about half of the weir
length. Figure 2 is a plot of the influent and effluent flows during
the study. The large discrepancy (6 mgd vs 15 mgd) at the start of the
study was due to clogging of the bubble tube and stilling well on the
influent Parshall flumes. On the second day of the study, the system was
flushed out and performance of the recorder improved; however, clogging
occurred again. On March 30, 1976 the head was measured on each of the
flumes and the flow rate was determined to be 13.4 mgd vs a flume recorder
reading of 8.2 mgd. The 13.4 mgd value agreed closely with the effluent
recorder reading.
The average daily effluent flow was calculated at 13.4 mgd from the
stage recorder charts on the effluent weir. Mean hourly flows varied from
8.6 mgd to a maximum of 19.2 mgd, which occurred during a heavy rain.
Approximately 40 percent of the total plant flow was industrial
wastewater from varied sources, i.e., meat packing, paper processing,
food processing, textiles, laundry, agrichemical, distillery, etc.
Return sludge flow (RSF) from the final clarifiers to manhole #5
can be varied, but was controlled at approximately 5 mgd (Figure 2) during
the study period, and was measured with a magnetic flow, meter equipped
with a recorder and totalizer.
WASTE CHARACTERISTICS AND REMOVAL EFFICIENCIES
Table I presents a chemical description of the influent and effluent
wastewater with calculated average percent reductions. Analyses were
made on 24 hour proportional-to-flow composite samples.
-8-
-------
/¦/ !
V/?3T:rtfATtR; ,4NO Rffuw SlU06E
FUy/3, ALbmw, (£a.
'• ~7J
/T
i
/;!
/:-!
¦\
\ A
jh>./
/
A
\. \
V
-¦}
\
\ i
:2_ <
r^/2 rj
c.-/"_'!•:
:vt"/
A
, / ^
;¦ i
! I
i / \ J
v v
w w
V
71
0 ' '
1
2 frrn* tsf*/£jt? ,%«-
/ (J}vrLua;r)
v
)
SiuzC-jr rJsM
r&isL™iiy±!>'rr °~gJ
N- z^--
\ V
\ /
V
,w
. i
H
V
•£' I
j3 /-;!
')
~7~?A'7,
ftiQ'jR)
H
-Vi
f\
-!h
-------
TABLE I
WASTE CHARACTERISTICS AND REMOVAL EFFICIENCIES
ALBANY, GA WTP
Parameter
Influent:
(nig/1)
Effluent
(ma/1)
% Reduction
BOD
COD
Suspended Solids
Total Solids
TKN-N
nh3-n
ko3-no2
Total Nitrogen
To tal-P
Pb
Cr
Cd
Cu
Zn
460
834
293
1015
28
88
371
224
84 2
19.4 .
10
.04
81
55
23
17
31
4 7
18.9
.02
28.02
14. 8
19.44
10.5
31
29
.093
.153
<.02
.077
.337
. 150
. 183
<.020
.095
. 327
Based on these BOD^ and COD analyses, it is apparent that the Albany
WTP receives a strong organic waste. In fact, the plant was designed to
treat 20 mgd of combined industrial and domestic waste with a total BOD^
loading of 45,420 lbs/day. Currently the hydraulic loading is 67 percent
and the organic loading is 113 percent of the project design loading.
Fortunately, this plant has the aeration capacity to handle this overload;
however, it points out the urgent need to monitor and control industrial
discharges to the system.
Because of the high carbon content of the wastewater and the presence
of filamentous bulking, a careful look was taken at the nutrient ratio of
carbon (B0Dr) , nitrogen and phosphorus. This ratio was calculated to be
100/10.5/5 ior BOD^/N/P which is near the recommended limits of 10/12/2 (5)
Based on these, data, it appears that there are no problems with the nutrient
balance of the waste.
Average solids removal during the three day period was very poor (23%),
due to the heavy loss of solids on March 31, 1976, because of bulking sludge.
This situation had been occurring at regular intervals (about weekly) for
the past few months. On.this particular date, the situation was aggravated
because one of four air compressors went out the previous night, producing
septic conditions in the final clarifiers.
In order to determine the hourly variation in organic loading, an
additional composite sampler was placed at the influent on March 31, 1976,
to collect hourly samples for COD analysis; Figure 3 is a graph of this
data with values ranging from 514 to 1,280 mg/1. The highest peak, observed
at 6:00 p.m. was probably due to infiltration, since it coincides with the
high plant flow, caused by heavy rain. Other peaks at 2:00 a.m. and at
-10-
-------
FIGURE 3
SPECIAL CCD ANALYSES
ALBANY, GEORGIA WTP
1900 2J00 2200 0100 0200 0500 C7C0
TIME - h 0 U R S
-------
8:00 a.m. on April 1, may indicate industrial process startup or slug
discharges. The average for the 24 hour period was 804 nig/1. This data
did not; show the presence of excessively strong slug discharges; however,
a review of plant data revealed that BOD^ influent values exceed 1000 mg/1
once or twice per month, with smaller peaks to 500-600 ing/] . On one
occasion, during a dry period, the flow rate entering the plant was 60 mgd
for a two hour period.
Hourly pH readings were taken on the influent flow (data in Appendix
A). These readings ranged from 5.0 to 7.8, which indicates the possibility
that acid wastes are discharged to the system. Wastewaters outside of
the pH 6.5-7.5 range, for any significant period of time, may have a detri-
mental effect on the activated sludge. Larger pli variations may kill the
biological process.
AERATION BASINS
Crab samples were collected at the discharge from each of the four
aeration basins (SLations A3, A4 , A5, and A6). Dissolved oxygen (DO) con-
centrations were measured at various locations in the aeration basins, and
the results are presented in Appendix B. Settlometer, TSS, VSS, and percent
suspended solids by centrifuge were run on each sample. Samples for micro-
scopic examination were grab samples, collected at the effluent collection
box.
The average mixed liquor suspended solids (MLSS) and mixed liquor
volatile suspended solids (MLVSS) concentrations were 2,866 and 2,610 mg/1,
respectively. The percent solids by volume, as determined by centrifuge,
ranged from 5.0 to 6.0 percent.
Presented in Table II are various activated sludge operating parameters
calculated during the study, and corresponding recommended values for the
conventional, plug-flow activated sludge process.
TABLE II
OBSERVED AND RECOMMENDED PARAMETERS FOR THE MODIFIED
CONVENTIONAL ACTIVATED SLUDGE PROCESS
Actual
Recommended (5)(6)
Hydraulic Detention Time (hours)
5.0
4.6
0.45
0.91
4-8
Sludge Age (days)
3.5-10
0.2-0.4
0.5-1.0
Lbs. BOD/day/lb MLVSS
Lb. COD/day/lb MLVSS
Lb. BOD/IOOO cu. ft.
MCRT (days)
Air (cu. ft./lb BOD)
Aeration Basin
73.2
2.9
1,393
40
5-15
800-1,500
-12-
-------
Settlometer test results are presented in Appendix A. The aver aye
volume, of settled mixed liquor s.ludge from all four basins after 60 minutes
of sett Ling was 73-80 percent which indicated a very sLow settling sludge.
Figure 4 is a plot of settling curves from each basin and is discussed in
the clarifier section of this report.
Data for dissolved oxygen (DO) profiles are presented in Appendix B.
Prior to the study, plant personnel were attempting to maintain DO levels
in the aeration basins at about 0.5 mg/1. This was being done to conserve
electricity and possibly to control the high concentration of filamentous
growth in the MLSS.
The first DO profile through each basin was conducted on March 30, 1976.
The data indicated that the major portion of all aeration basins was at
essentially zero mg/1 DO concentration. An exception to this condition
was observed in nitrification tank IfI where the DO level was high. This
was because tank #1 was receiving a very small portion of the centrate
return, due to poor flow splitting into tanks N-l and N-2. It was also
determined that the electronic DO meter used at the WTP was reading 0.5
mg/1 in a 0.0 mg/1 DO solution. The very low concentrations in the basins
did not provide sufficient air for the MLSS, and the clarifier contents
and return sludge was septic. This resulted in a poor quality return
sludge and a predominance of filamentous growth in the MLSS which produced
a classic bulking sludge.
The air flow delivered to the aeration basins on March 29, 1976 was
14,000 cu. ft./min. in the 8 psi diffuser system and 17,000 cu. ft./min.
in the 4 psi system with an even split between the head and discharge
ends of the aeration basins. After running the DO profiles, the air
flow rates were increased to, 17,500 and 20,000 cu. ft./min. in the
respective systems; however, compressor problems prevented maintaining
a sustained supply. On March 31, 1.976 blower problems were corrected
and a sustained supply was maintained. At a rate of 17,500 and 20,000
cu. ft./min the air to BOD^ ratio was 1500 cu. ft./lb of BOD^ removed.
Additional DO measurements (Appendix B) dictated increased air supplies,
so on April 1, 1850 cu. ft./lb of BOD5 was added. This level finally
brought the DO concentrations in the aeration basins up to an acceptable
level. This excessive air demand was probably due to the partially
septic conditions which had existed, the large concentration of filamen-
tous growths and to the high demand of a young, overloaded sludge. After
the study, as a better quality sludge was developed, the air requirement
dropped considerably. Table III is a tabulation of aeration basin DO
concentrations at selected stations.
-13-
-------
-------
TAJ3LE III
DO CON CEN TKAT1ONS AT SELECTED STATIONS*
Stations DO (mp./ L)
3/30 " 3/31 " A/1 4/2
1 ft.-5 ft. 'i ' rt.-j It. 1 ft.-5 ft. 1 ft.-5 ft.
(28,600 ft3/mi.n) (38,800 ft3/r,iln) (4 8,500 ft3/inln)^-'=
A3-1
0.8
0.6
1. 8
1.1
2.6
2.4
4.6
4.2
A3-9
0. 4
0.0
1.8
1.4
2.0
1.0
3.0
2. 7
A4-17
0.3
—
0.2
0.1
0. 2
0.1
0.6
0.4
A4-26
—
—
0.5
0.7
0.5
0.3
3.6
3.6
A5-18
0.4
—
0.2
0.1
0. 7
0.5
1.6
1.4
A5-25
—
—
0.2
0.1
1.4
1.4
3.8
3.7
A6-19
0.4
—
1.2
0.7
0.6
0.4
2.8
2.8
A6-24
—
—
0.6
0.8
2.4
2.5
4.2
4.4
Nl-20
3.9
—
0.6
0.4
2.7
2.2
5.2
5.0
Nl-23
5.7
—
5.1
5.0
4.2
4.0
6.6
6.4
N2-21
0.2
—
0.2
0.1
0.2
0.1
0.4
0.1
N2-22
0.6
—
0.5
0.2
0.4
0.2
2.2
2.2
*Sc-c Appendix B for station locations and additional data
;V*Ai r flow irate supplied to the aeration basins.
EXAMINATION OF MICROSCOPIC ORGANISMS
A determination of the quality of an activated sludge can be made by
a microscopic observation of the sludge appearance and of observed changes
in Protozoa species as bacterial floe develops. Figure 5 is a graphic
generalization of what is to be observed when making a microscopic examina-
tion of different phases of the aeration process.
-15-
-------
FIGIJlili 5
POPULATION, DYNA>n.CS IN AEROBIC WASTEWATER TREATMENT (9)
PROCESS
Or;uu Lc H.itCe r (c'oad)
A particular sludge can be classified into the following general
groups according to age and predominant groups of organisms.
I. Young Sludge - Solids dispersed, fluffy, light tan in color, protozoa
population heavy with a good mixture of flagellates, free-swimming
ciliates and amoebae. Solids settleability poor.
II. Mature Sludge - Individual solid particles flocculating, settleability
fair with spongy blanket. Protozoa population consist of a sparse
population of flagellates, numerous stalked ciliates, rotifers,
oligochaetes, and crawling ciliates.
-16-
-------
III. Stable sludge - Solids comivu: l, tan to dark brown in color, forming
.1 good, heavy floccuianl mass that settles uniformly >50% by volume.
Protozoa populations consisting of stalked caliar.es, rotifers ,
crawling ciLintes, and oligochaetes.
IV, Very stable to old sludge - Solids very heavy, clumped, black to dark
grey in color, settles very fast, leaving straggler solids dispersed
throughout the supernatant. The protozoa population consist primarily
of crawling ciliates.
The activated sludge system (mixed liquor and return sludge) at the
Albany WTP can be characterized as having similar conditions as Groups I
and II of Figure 5. Compounding the problem of poor settleability
was the presence of a very heavy growth of filamentous organisms. Filamen-
tous growth may be caused by variable pH, nutritional deficiencies, low
dissolved oxygen (DO) or other conditions. Control of these growths may
normally be accomplished by correcting one or more of the forementioned
causes. Low dissolved oxygen concentrations were measured in the aeration
basins. As the dissolved oxygen concentrations were increased, sludge
settleability increased, the concentration of filaments decreased and the
sludge was aged slightly with stalked ciliates becoming rather common.
Similar conditions were observed in the nitrification basin, with one
basin containing adequate DO (N-l) and one with low DO (N-2)„ Conditions
in the nitrification basin with adequate DO demonstrated populations
similai to Group III plus heavy filamentous growth, but the solids concen-
tration was low.
To determine if the filamentous growth was being continually introduced
into the aeration system, samples of raw influent and primary effluent
were examined. Samples from each source revealed the presence of the
filamentous growth. Tufts of fungal filaments were found in the raw
wastewater stream, while only small fragments of filaments were found in
the primary effluent. Numerous fungal filaments were returned in the
thickener overflow and digester supernatantt
OXYGEN UPTAKE RATES
The oxygen uptake rate is a measure of the general sludge activity,
i.e., the biodegradability of a particular waste by a particular activated
sludge. This activity is measured by mixing return activated sludge
with influent (fed) and nonchlorinated effluent (unfed) and determining the
uptake rates and calculating the load ratio.
Load Ratio - ADO (PPm/min) fed sludge
ADO (ppm/min) unfed sludge
The detailed procedure for this test is contained in Appendix E.
In general, a load ratio in the 2 to 5 range indicates a readily biodegradable
waste. It also Indicates that the sludge is well acclimated to the waste
and that pH, temperature and other environmental conditions are favorable.
-17-
-------
Lower ratios may indicate toxic waste or unfavorable environmental conditions,
A very young, actively growing sludge produces a high ratio due to the
high rate of oxygen.uptake. Table IV shows the results of the uptake
tests.
TABLE IV
OXYGEN UPTAKE RATES
Date
Time
%RS
3/30/76
1100
63
3/31/76
1525
53
4/1/76
1030
42
Average O9 Uptake
mg/X . mg/1
lTDC^1'
URS^'
0.96
0.74
0.46
FRsj7
2.9
2.4
1.78
Load Ratio
FRS/URS
3.02
3.24
3.86
1/ - URS - United Return Sludge using clarifier effluent
2/ - FRS - Fed Return Sludge using raw influent from primary
settling basin.
These data show a rather high load ratio which is a result of rapid
oxygen uptake. This is typical of young sludge. Thus> it should be
expected that a rather large amount of air would be required in the
aeration basins and that an unusually high demand would be present at the
head end of the tanks due to the very rapid growth.
CLARTFIERS
The primary problem encountered with the clarifiers was bulking sludge
resulting in excessive solids carryover. This situation was partially
due to the heavy filamentous growth in the sludge producing very poor
settling characteristics (Figure 4). Turbidity of the clarifier effluents
ranged from 6-10 NTU when there was no solids carryover to 1,260 NTU during
bulking. Plant effluent settleable solids for the 24 hour composite
sample collected on April 1 were 250 ml/1. This is typical of the cyclic
loss of solids which had been experienced at the plant for the past several
months.
Dye was injected into the aeration basin effluent in order to deter-
mine the flow split and detention time in each clarifier. Concentration
curves are shown in Figure 6. These curves indicate that the flow split
to each clarifier is very good with very similar concentration curves-^for
each clarifier. Clarifiers //3 and //4 received slightly more flow than
//1 and //2. The centroid of each dye curve was approximately 1.3 hrs. after
the dye was introduced into the clarifiers. This figure represents the
average detention time. Plant flow during the dye study was 11 mgd, and
the return sludge flow rate was 5 mgd.
-18-
-------
280
260
240
220
200
180
160
140
120
100
80
60
i\
I \
I \
FIGURE 6
CLARIFIER DVE TRACER STUDY
CLAR1FIER NO. 1
" NO. 2
" NO. 3
G r~G a NO. 4
Time
-------
The observed and recommended hydraulic loading, solids loading, and
weir overflow rates for final clarifiers following activated sludge are
presented in Table V.
TABLE V
OBSERVED AND RECOMMENDED PARAMETERS FOR SECONDARY CLARIFIERS
Observed Recommended (2)(3)(6)
Hydraulic Loading (gpd/sq. ft.)
Solids Loading (lbs/day/sq. ft.)
Weir Overflow Rate (gpd/ft.)
Detention Time (hrs.)
526
12.5
11,828
2.15*
400-800
20-30
<15,000
2.5
^Calculated based on displacement - dye study revealed 1.3 hrs.
As shown in Table V, the clarifiers are sized to adequately handle
existing loads.
The data presented in Figure 4 indicates that the poor settling sludge
may be responsible for the excessive solids in the effluent. The lower
curve in this figure also shows that with increased air supply, an almost
perfect settleability curve was obtained after a three week period. This,
however, did not produce a satisfactory effluent,, indicating problems with
the sludge collection and removal mechanism in the clarifiers.
DISINFECTION
Chlorine gas is used to disinfect the treated wastewater effluent, to
disinfect excessive storm water inflow and to control odors in the raw
sewage influent. The chlorine is fed by use of a system of four chlorinators—
three are automatically controlled by the WTP flows, and one is manually
operated.
Chlorine gas is fed into the final clarifier effluent at Manhole No.
8. From Manhole No. 8, the effluent flows to the chlorine contact struc-
ture which provides a 30-minute detention time at 20 mgd. The plant outfall
line is of sufficient length to provide the additional detention time needed
at higher flows.
At a dosing rate of 1000 lbs/day, a total residual chlorine of
<•05 mg/1 was measured on March 31 and 5.27 mg/1 on April 1. This differ-
ence was due to a tremendous solids carry-over taking place when the
March 31 samples were collected.
-20-
-------
SLUDGE HANDLING
Two digesters were out of service for repairs during the study, and
a third was unheated. Parts for the heat exchangers had been on order for
several months, and interior piping was being replaced in one of the
digesters. All repairs were expecked to be completed by May 1976.
With two digesters out of service, all sludge was pumped into the two
remaining operational digesters. They were operated in series with the
heated unit as a primary, and the unheated unit as a secondary digester.
The units were overloaded, with a sludge detention time of less than
ten days, and a pH of 5.4 in the primary and 6.4 in the secondary. Gas
production was very low and of poor quality.
Primary and waste activated sludge is passed through an air flotation
sludge thickener where the solids concentration is brought up to seven or
eight percent before putting it into the digesters. The thickener overflow
is returned to manhole //5 where it flows into the aeration basins. This
sidestream is a significant.load amounting to approximately 1 mgd with a
1000 mg/1 BOD^ concentration.
Sludge is dewatered by centrifuge with the centrate returned to the
aeration basins. Due to poor digester operation and the lack of polymer
use, the centrate quality was very poor (COD averaged 40,000 mg/jL)» De-
watered sludge is trucked to a landfill. A few old sand drying beds
are available for use as needed.
LABORATORY
The laboratory at the Albany WTP is staffed by a chemist and two
technicians. The chemist's duties were divided between plant operations
and laboratory work. As a result, problems could arise with the more
complicated analytical procedures. It would be best if the chemist could
spend more time in the laboratory to insure the highest quality sample
handling and analytical techniques, especially since critical plant
controls depend on the laboratory data.
Obtaining a representative sample is an important part of laboratory
quality control. At present, the influent and effluent composite samples
are of little or no value. The influent sampler is either clogged or
inoperative most of the time. The effluent composite sampler is positioned
on only one of the four secondary clarifiers. In order to obtain a true
evaluation of the effluent, it will be necessary to get a sample after
the flows have combined from all four clarifiers. Care should also be
exercised in selecting sampling stations within the plant for process
control.
-21-
-------
At the time of the study, the settleability of the solids in the
aeration basins was being determined in a one liter graduated cylinder.
It was suggested that the 2 liter settlometer be used since this reduces
side wall interference and more closely represents clarifier conditions.
At the conclusion of the study, the settlometer test was being initiated
in the daily plant control routine.
During the study, dissolved oxygen in the aeration basins was being
monitored by plant personnel with a portable electronic DO meter. The
WTP DO meter was checked and found to be very unstable yielding question-
able data. Since the study was completed, WTP personnel have related by
telephone that the instability was due to weak, batteries, and that this
had been corrected.
-22-
-------
REFERENCES
1. "Process Design Manual for Suspended Solids Removal", US-EPA
Technology Transfer, January'1975.
2. "Process Design Manual for Upgrading Existing Wastewater Treatment
Plants", US-EPA Technology Transfer, October 1974.
3. "Sewage Treatment Plant Design", American Society of Civil Engineers,
Manual of Engineering Practice No. 36, 1959.
4. "Recommended Standards for Sewage Works", Upper Mississippi River
Board of State Sanitary Engineers, Revised Edition, 1971.
5. "Wastewater Engineering", Metcalf and Eddy, Inc., 1972.
6. "Operation of Wastewater Treatment Plants", A Field Study Training
Program, US-EPA, Technical Training Grant No. 5TT1-WP-16-03, 1970.
7. "Standard Methods for the Examination of Water and Wastewater",
13th Edition, 1971.
8. "Modernization of the BOD Test for Determining the Efficiency of
Sewage Treatment Processes", Sawyer and Bradney, Reprinted from
Sewage Work Journal, Vol. XVIII, No. 6, November, 1946.
9. "Microorganisms in Water", Laboratory Analyses in Treatment Plant
Operations, FWPCA, October 1968.
-23-
-------
Appendix A
Loborncory' D.:i
*ALb.r.iy K.iiLJvatjr 1 tv.icn.^ru P1 :ic
' ) K *1 ^ \_ ry •" ¦
Influent, H flu-Mir ¦ i'-c1 Primary Cl.irif'i-r v f 1u'm-.c
\
1
7"
. j STATION"
**
o
«
1
>*
i i svy 12'' i.r*. j,m j ¦ ¦¦
1 i
I
j :' -
T
¦ -> '/f; ! 7c : 1500 ! 533
32.31 19.51 .02
15
1 5(1
-------
A^;>cr,di>. A (continued)
L.T^or.-uorv, D.,L.t
¦Vib.'iny '•.V.»:e,.vacor 1 Vc.iLu.jr.c P1 ar;
\lhr;
fVnr"
Special COf> Annlvso.s
I
NJ
Ln
I
C - .-a | —
09:>:i ! 1-1 76 0900 1 70 j !
1
I 1 ! f 1 I I- I l~\
" i r 1
n't""
y • ' ' ' 1 i I < i
! 2 : 1 1 1 i 1 , 1000 j £93 1
' 1
i 1 ! 1 i 1 1 i 1 J
! !
1
3 ! i i
' 1 ' I'OO 1 7i1 i
i
... 1 1 ..J .
1
1
1
1
i
1
; . i
1
! 1 ! 1200 1 925
1
wiili car
1 irv! il "icn.r
1 • 1 s i 1 1
j hourly sp-nltJ boin<: rvif1
• 5 |
i
1
I 1300 j 759
foi COD
in.-ilvslis ."is
. u . 1. . .
1 cncck ror j hic.i
, < 1 r
1 online fro
1
' —j
; 6 1
I
1
1 U00 ) S37
b.i^ch di
chj r ci n;^.
! 1.
7 1
1
1
1
j 1500
917
f i
f
! ! s i
j
j ItCO j s:.s j
| I
I
I
1
i i 9 Mi
1
1
J 1700
917
1
j
1
i
1 ¦ 10 1
1
1
f •
I ISOO jl2fc0
1
j
j
1
]
i ! ii i
!
1
) 1900 |] 031
i : :2 !
! ! !
j 2C00 j 664
1
¦
I
L_ L
1 i -3 III
:
t 2:00 ! 60i
1
1
! l-i
I
!
1 1 '
! 1
!
i i Ji
I
1 1 2:00 j 913
!
¦i ! J
!
i
! ! 15 1
i
i
| I 2300
597
i
1
1
1
! ! i6 !
1
i 1
2400 j 634
If
'1
1
1 i 17 lli
i i
03 00
60]
If
I
1
r
la ill.
14
con !
1
1
i:i
Mi
I
1
t
l
t
;
! ! 1 U 1 1 I
! 1
1
I
i
1
-------
Appendix A (concir.iiecj)
Laboratory Dacla
• J j
Alb'any Wastewater Treatment Plant
Albany, Georgia
Special'COD Analvses
-------
Appendix A (continued)
Laboratory Data
Albany Wastewater Treatment Plant
A1 'vin v ,__LGc_or L'-'j ^
Aeration Basins
0 i K
sno
STATION"
H
o
TIME
0876
1 A-l
3
130 |76
0900
99
98
96
' 9*6
95*1 95
90 | 83
84 I Fluffjy; ¦bounded
5.5 | 3300
2650
0377
A-2 J 3
30
76
0900 | 99
98
96
96
95
93
8&- | 83
7S
settled un
venly
'5.5
3275
2650
l - I
oes7
A
-3 1 3
30
76
1545 | ~
-
-
-
- ¦
- ' -
- I "
-
-
-
-
13.5
03? f
1
I "?
31
76 ! im
I
99 1 99
97
95
95
94
90
86
83
flufT
y, unijven
¦5.0
3125
2625
0913 !
1 4 ! '1
76 ! 0040 ! 97'
96
94
91
89
86
30
75
73 | set:!
: r.,c
I -
3075
24 75 |
- i
052? i
r
4
2
76
0S50 | 98
95
95
95
85
80
73
• . 70
6S
cl Gar
suce
"natanj; —
—
—
—
0S3S
A-
-4
3
30'
76
1545
¦
! __
13.0
1 1
i
0997
. ! 3
31
76
1115 i 99
99
98
96
95
93
89
88
80
5,0
3?on
9 750
-
0914 j
4
i j 76
0940
98
97
93
•
92
90
89
85
84
80
-
3075
2500
- i
1
<
1
0335
A-5
3 | 30
¦76
15 45.
—
-
—
—
-
I _
—
—
—
12.2 t
0333
3
31 ! 76
1115
99
99
98
96
93
88.
84
[ 80
77
s.l
"307?
2S7S
- ¦
0916
*
4
1 | 76
0940 97
96
95
94
• 94
90
87
1 8,
80
3180
9 Mn
—
0390 ' A-6
3
1.
30 I 76
1545
; ,
i 1
—
—
—
13.0
CS95 !
3
31
76
ins.
99
99
98
94
90
S8
SO '|!! 70
. 75
6.0
3150
2600
-
r»»
o-»
o
4
1
76
0940 98
97
95
• 94
94
94
94
i 94
as
— '
3275
267 S
-
I
1
J
1
1
1
|
f
!
I
1
J
I
1
1 1
'i
i
.1
i
1
1
' 1 ! !
ii
1 1
1
1
I
-------
-------
Appendix A ('continued)
Laboratory Data
Albany. Wastewater Treatment Plant
Albany, Georgia
Thickener Overflow, Centrate, Anaerobic Dlgestors and Return Sludge
1
*
j
0 -f A\
s-->0
STATION"
P
1
o
<
l:-
TIXE }
' j
rnr
! ~
p-«
>•
1
7 ^
^/c- ic/ ^ < <
> \ Ac ,
^ ^vL
SV/
OS^'A j to_i j 3
1 31 j 76
1345
740
1675
59.0
29'. 2
.01
36.5
1 260 j 540 |<20 1 220
910 1
1.0 -
~T~ 1 f
0911
!
4
1
"76
I
1400 ! 1320
2690
77
20
.02 I 42 L500-
Bio 1
VO
I
-------
APPENDIX A (continued)
Hourly pK Reading on Influent Wastewater
Albany, Georgia
Date 1976
/ /
3/30
3/30
3/31
3/31
4/1
4/1
4/2
I !
l •
AM
1:00
py
1:00
5.9
| -\!-l
| 1:00
6.6
PM
1:00
6.6
AM
1:00
6.7
PM
1:00
6.4
AM
1:00
6.5
1
i j
2:00
2 : CO
7.0
2:00
7.1
| 2:00
6.9
!
2:00 6.9
2 :00
6.6
! 2:00
6.5 i !
i i
i i
3:00
3 :Oo| 6.7
3:00
1 |
6.9 | 3:00
6.9
( 1 1 i 1
| 3:00; 7.0 | j 3:C0| 6.5
1 3:00
1
6:5! !
; i
' f
« r
1 1
4:00 ! I
4:00
6.4 i
1
4:00' 6.8
[ 4:00
6.8 | J 4:00j 6.9 | | 4:0oj 6.5
j 4:00 j 6.3 j ! ;
I
i
i
5:00 | j
5 -• ooj 6.3
5:00; 6. 9 J
5:00
6.7
5:00| 6.7|
1
5 ;OOj 6.4
5 :00 j 6.5
i ;
i
1
*-
1 1
6 :00 j |
I
6 :OOJ 7.1
1
6: OO) 6.9
6:00
6.3
6:00; 6.7
6: Ooj 6.5
t
6:00 | 6.6
1
\ j
7:00
1 1 i
j | 7 :CO] 6.9
| 7:00
1
6.8 |
7:00
6.7
7:00| 6.3
7 :Ooj 6.5
7:00 S 6.6 i 1 !
1 1 1
' ! ! I
! | | 8:00| 6.6
8:00
7.1
8:00
6.7
8:00
6.8
8 :CCj 6 .3 j
S: 00! 6.5
8:00
1 1
1 ! !
! j ! 9:00
7.0
9:00
7.4
9:00
6.6| i 9:00
6.5
9: Ocj 6.3
9 :00- 6.5'
9:00
1 1
i !
1 I ' i
! 1 (10: r.O; 6.2
| 1
[10:0oj 7.7
10:00
6.8
| 1
jL0:00 ) 6.8
j 10 :00? 6.6 j j 10 : Ooj 6.6 j
10:00 j
i !
! i
1 1 ! ' 1 i '
- ; 111:00J 5.0 } |ll:00j 6.5
i 11:00
6.5
Jll:00 j 6.9
1 |
11:00 6.3l
11:0C> 6.5
11:00
1 ' 1
1
! ) 1
j j jXoon j j
i ! J12:00I 6.3 |
12 :Oo| 7.8
isoon
12:00
! 1
6.8 (12:00
1
6.9 j
12:Ocj 6.6 |
12 :Ooj 6.4 |
J^/.l
12:00
1
i (
! 1
i :
|
I
1
i
1
j
i
! !
1 !
!
1 i
1
i !
! i
l
<
!
1
1
I
1
1
i 1 ! i
lit'
II!
1
i
|
!
1
1 i
I 1
II!:
II!
j
! i
i 1
! !
i !
1 )
i 1 i
i 1 1 !
1 1 ¦ !
I
u>
0
1
-------
Appendix B
Dissolved Oxygen Profiles
Albany, Georgia
3asin
AB-1
A3-2
I
U)
AE-3
A3-4
NB-1
N3-2
26
27
23
29
30
13
25
31
32
34
37
19
24
33
35
36
40
20
23
38
41
43
45
21
22
29
42
44
46
26
26
26
26
26
26
3/30/76 1000 - 1100
0.4
0.4
3.7
5.7
0.2
0.6
Station
Ter.p °C
1 ft.
5 ft,
1
26
0.8
0.6
2
26
0.6
3
26
0.7
0.4
4
26
0.6
5
26
0.1
0.2
6
26
0.2
7
26
0.1
0.0
8
26
0.1
0.0
9
26
0.4
0.0
10
26
0.1
0.0
11
26
0.0
0.0
12
26
0.1
13
26
0.1
0.0
14
26
0.2
0.1
15
26
0.2
0.2
16
26
0.2
0.1
17
26
0.3
P.O. £g/l @ specified depth
10 ft.
0.2
12 ft.
0.2
0.0
0.2
0.1
0.0
0.0
0.0
0.0
0.0
0.0
0.1
0.1
0.1
0.3
0.2
0.2
3.4
0.1
Aeration Basin D.O. Profile Stations
15 ft.
0.2
0.0
0.0
0.0
0.0
0.0
0.0
0.1
0.1
Centrate
Influent
39
Basin
KB-2
42
21
44
46
22
38
Basin
NB-1
41
20
43
45
23
j ^
33
Basin
A3-4
35
19
36
40
24
32
Basin
AB-3
34
18
37
31
25
o
28
17
29
30
27
Basin
AB-2
26
affluent
16 15
Basin
A3-1
14 13
.2 11 10
9 "
7 6
• #
5 4
3 2
1
T
-------
Appendix B continued
Dissolved Oxygen Profiles
Albany, Georgia
3/31/76 1450-1515 4/1/76 1115-1530 4/2/76 0945-1030
D.O. raf»/l P.O. ir.q/i Q P.O. r.g/1
Easin Station Tea? °C 1 ft. 5 it. Tenp °C 1 ft. 5 fc. Te~p C 1 11. 5 ft.
AB-1 1 27 1.8 1.1 26 2.6 2.4 26 4.6 4.2
2
3
4
5 26 1.7 1.4
6
7 26 0.6 0.4 26 3.2 3.0
8
9 27 1.8 1.4 26 2.0 1.0 3.0 2.7
¦ 10
11
12
13
14 26 0.1 0.0
15
16 26 0.1 0.0 26 0.4 0.3
A?.-2 17 27 0.2 0.1 26 0.2 0.1 26 0.6 0.4
26 27 0.5 0.7 26 0.5 0.3 26 3.6 3.6
27 26 0.1 0.0 26 0,3 0.3
28 26 0.1 0.1
29 26 0.4 0.2
30 26 0.3 0.2
AB-3 18 27 0.2 0.1 26 0.7 0.5 26 1.6 1.4
25 27 0.2 0.1 26 1.4 1.4 26 3.8 3.7
31 26 0.2 0.1
32 26' 0.4 0.2 26 0.1 0.0
34 26 0.2 0.1 26 0.3 0.2
37 26 0.2 0.1 26 2.9 2.7
AB-4 19 27 1.2 0.7 26 0.6 0.4 26 2.8 2.8
24 27 0.6 0.8 26 2.4 2.5 26 4.2 4.4
33 26 0.2 0.1 26 0.2 0.1
35 26 0.6 0.6 26 0.8 1.2
36 26 0.2 0.1 26- 3.6 3.2
40 26 0.4 0.1
NB-1 20 28 0.6 0.4 26 2.7 2.2 24 5.2 5.0
23 27 5.1 5.0 26 4.2 4.0 24 6.6 6.4
38 26 0.2 0.1 25 0.6 0.8
41 26 1.9 1.7
43 26 4.6 4.3
45 26 4.0 3.8
NB-2 21 28 0.2 0.1 26 0.2 0.1 26 0.4 0.1
22 28 0.5 0.2 26 0.4 0.2 26 2.2 2.2
23 0.1 0.0 27 0.0 0.0
39
42 28 2.2 0.1
44 28 0.4 0.2
46 28 0.2 0.1
-------
APPENDIX C
GENERAL STUDY METHODS
To accomplish the stated objectives, the study included extensive-
sampling, physical measurements and daily observations. Plant influent,
primary effluent, and WTP effluent Stations I, PE, and E, respectively,
were sampled for three consecutive, 24 hour periods with ISCO Model
1392-X automatic samplers. Aliquots of sample were pumped at hourly
intervals into individual refrigerated glass bottles which were composited
proportional to flow at the end of each sampling period.
An additional sampler was installed at Station I to collect individual
hourly samples for COD analysis. A Steven stage recorder was installed on
the WTP effluent to determine plant flows. An additional recorder was
installed on the aeration basin influent. Hourly WTP totalizer flows
were used for all inplant stream flows during the study period.
Dissolved oxygen was determined initially at all stations throughout
the plant, and thence daily at stations in the aeration basins using a
YSI Model 51A dissolved oxygen meter.
Hourly influent pH variations were determined from the individual
samples of the 24 hour composites. Daily pH determinations were made at
selected stations on the plant site.
Temperature was recorded while measuring the dissolved oxygen concen-
tration. Individual samples of the two, 24 hour compositing periods were
used to determine hourly influent pH variation.
Depth of the secondary clarifier sludge blankets was determined
daily using equipment suggested by Alfred W. West, EPA, NFIC, Cincinnati.
Sludge activity was determined by the oxygen uptake procedure presented
in Appendix E.
A series of standard operational control tests were run daily:
o Settleability of mixed liquor suspended solids (MLSS) as determined
by the settlometer test.
o Percent solids of the mixed liquor and return sludge determined
by centrifuge.
o Suspended solids and volatile suspended solids analysis on the
aeration basin mixed liquor and-return sludge.
o Turbidity of each final clarifier effluent.
-33-
-------
Rhodamine WT fluorescent dye was used to determine the flow pattern
and the actual detention time of the clarifiers.
The BOD5 procedure deviated from standard methods (8). Samples were
set up at the study site and transported within the incubator to Athens, GA.
The samples were removed to an incubator at the laboratory facility. Time
of travel was four hours, and incubator temperature on arrival at Athens
was 21°C. Temperature determination was made using a calibrated thermometer
placed in a BOD bottle of distilled water incubated along with the samples.
An amperometric titrator (Fischer & Porter Model 17T1010) was used to
determine effluent chlorine concentrations.
Visual observations of individual unit processes were recorded.
Mention of trade names or commercial product does not constitute endorse-
ment or recommendation for use by the Environmental Protection Agency.
-34-
-------
APPENDIX D
Activated Sluclge
Formulae Used For General Calculations
Aeration Basin
1. lbs. of solids in aeration basin
Basin volume = ro.g.; MLSS (conc.) = mg/1 '
(MLSS cone) x (Basin vol.) x 8.34 = lbs. of solids
2. Aeration basin loading (lbs. BOD or COD/day)
Inf. flow to aeration basin = mgd
Inf. BOD or COD = mg/1
(iiuu or cujj; x J.J.UW /w o. Jk vy wx/ y
3. Sludge Age (days)
MLSS conc. (avg. of daily values) = mg/1
Aeration Basin Vol. = m.g.
TSS, Primary Eff. or Basin Inf. conc. = mg/1
Plant Flow = mgd
(MLSS) x (Basin Vol.) x (8.34)
(TSS) x (Flow) x 8.34
4„ Sludge Vol. Index" (SVI)
30 min. settleable solids (avg. of daily values) =
MLSS conc. = mg/1
(%, 30 min. set. solids) x (10,000)
MLSS
5. Sludge Density Index (SDI)
SVI Value 100
SVI
6. Detention time (hours)
Volume of basins = gal.
Plant flow = gal./day
Return sludge flow = gal./day
Basin volume x 24
Cf
10
(Flow) + (Return sludge flow)
7. F/II Ratio (Food/Microorganism) BOD or COD
Basins Inf. B0D5 conc. (avg. or daily value) = mg/1
Basins Inf. COD conc. (avg. or daily value) = mg/1
Plant Flow = mgd
MLVSS conc. (avg. or daily value, note Volatile SS) = mg/1
Basin Vol. = m.g.
(BOD.s conc.) x (plant flow) x (S.34) = pnn/iv.
(MLVSS) x (Basin Vol.) x 8.34 it>S- 130D/-I-D-
-35-
-------
(COD conc.) x (plant flow) x (8.34) rnn/n -trv-
(MLVSS) x (Basin Vol.) x (8.34) lbs" COD/lb. MLVSS
8. Mean cell residence tirae (MCRT) = days
MLSS conc. (avg. or daily value) = mg/1
Basin vol. = m.g.
Clarifier vol. = mrg.
Waste activated sludge conc. - mg/1
Waste activated sludge flow rate=mgd
Plant effl. TSS = mg/1
Plant flow = mgd
(MLSS) x (Basin vol. + Clarifier vol.) x 8.34
^ A. - ™ J* ^ J ml •< J n a 't 'N ¦* r ( r»4- -p 1 \ ' >r O O /} _i_ S
\ M UiW" w Vy CA. W b >. V M SA v_» V*. V# ^ a y - - y •> M w — — ^ w « w ««
(Plant em. T55 ^ pla.r,t flcv; r « 34)
Clarifier
1. Detention tirae = hours
Plant flow to each clarifier = gals/day
Individual clarifier vol. = gals.
(clarifier Vol. (each) x 24 _ jlours
Plant flow + Return Sludge Flow"
2 Surface loading rate = gal./day/sq. ft.
Surface area/clarifier = sq. ft.
plant flow to clarifier = gal./day
Plant flow to clarifier = _/d / _
Clarifier surface area
3. Weir Overflow Rate (gal./day/lin. ft,)
Weir Length = ft.
Plant flow to clarifier = gal./day
Plant flow n
Mr length = 6*1./day/lin. «
-36-
-------
APPENDIX E
OXYGEN UPTAKE PROCEDURE -
A. Apparatus
1. Electronic DO analyzer and bottle probe
2. Magnetic stirrer
3. Standard BOD bottles (3 or more)
4. Three wide mouth sampling containers (approx. 1 liter each)
5. DO titration assembly for instrument calibration
6. a t-ofl r> ir 1 ¦? i-> >• /OCrt —1 \
* ----- — ^ /
7. Adapter for connecting two BOD bottles
B. Procedure
1. Collect samples of return sludge, aerator influent and final
clarifier overflow. Aerate the return sludge sample promptly.
2. Mix the return sludge and measure that quantity for addition
to a 300 ml BOD bottle that corresponds to the return sludge
proportion of the plant aerator, i.e. for a 40% return sludge
percentage in the plant the amount added to the test BOD
bottle is:
300 X .4 = 120 = 86 ml
1.0 + . .4 ' 1.4
3. Carefully add final clarifier overflow to fill the BOD bottle
and to dilute the return sludge to the plant aerator mixed
liquor solids concentration.
4. Connect the filled bottle and an empty BOD bottle with the
BOD bottle adapter. Invert the combination and shake vigorously
while transferring the contents. Re-invert and shake again
while returning the sample to the original test bottle. The
sample should now be well mixed and have a high D.O.
5. Insert a magnetic stirrer bar and the previously calibrated
DO probe. Place on a magnetic stirrer and adjust agitation
to maintain a good solids suspension.
6. Read sample temperature and DO at test time t=0. Read and
record the DO again at 1 minute intervals until at least 3
consistent readings for the change in DO per minute are
obtained (ADO/min). Check the final sample temperature.
This approximates sludge activity in terms of oxygen use
after stabilization of the sludge during aeration (unfed
sludge activity).
-37-
-------
APPENDIX E (Cont)
7. Repeat steps 2 through 6 on a replicate sample of return
sludge that has been diluted with aerator influent (fed
mixture) rather than final effluent. This A DO/minute
series reflects sludge activity after mixing with the new
feed. The test results indicate the degree of sludge
stabilization and the effect of the influent waste upon
that sludge.
The load factor (LF), a derived figure, is helpful in evaluating
sludge activity. It is calculated by dividing the DO/min of fed sludge
by the DO/min of the unfed return sludge. The load ratio reflects the
conditions at the beginning and end of aeration. Generally, a large
loLuot means aDunaanc, acceptable teed under favorable conditions. A
small LF means dilute feed, incipient toxicity, or unfavorable conditions.
A negative LR indicates that something in the wastewater shocked or
poisoned the "bugs."
Taken from "Dissolved Oxygen Testing Procedure," F. J. Ludzack and
script for slide tape XT-43 (Dissolved Oxygen Analysis - Activated Sludge
Control Testing) prepared by F. J. Ludzack, NERC, Cincinnati.
-38-
-------
APPENDIX F
DESIGN DATA
THE METROPOLITAN ALBANY WASTEWATER TREATMENT PLANT
ALBANY, GEORGIA
DESIGN FLOW
Average
Peak
20 mgd
60 mgd
PRELIMINARY TREATMENT
Bar Screen
Number
Screening range
Capacity
Bar Spacing
Velocity
Area
Slope
2 units, mechanically cleaned
0.5 to 5.0 ft. -Vrng
30 mgd
1 inch
0-3 ft./sec.
15.5 ft.2
84 inches
Parshall Flumes
Number
Dimension
Width
Height
Throat
Capacity
2 units
A.5 ft.
7.42 ft.
3 ft.
0-30 mgd each
Grit Removal
Number
Dimensions
Length
Width
Depth
Capacity
Velocity
Blowers
Capacities
Surface Loading
Raw Sewage Pumping Station
Number and Capacities
PRIMARY CLARIFIER
Number of tanks
Dimensions
Length
Width
Depth
Wetted Volume
2 units, aerated
53 ft.
20 ft.
17 ft.
30 mgd each
1 ft./sec.
3 units
30 hp each, 75 7 CFM @ 7 psi
14, 150 gal./day 1 ft.2
6 - 4900 gpm @ 75 hp
2 - 2100 gpm @ 30 hp
4 rectangular
78.67 ft.
40 ft.
11.42 ft.
35,936 ft."^ each
268,800 gal. each
143,746 ft.3 Total
1,075,200 gal. Total
-39-
-------
Detention Time @ 20 mgd
Surface Loading Rate
Sludge Collectors Ea. Tank
1.29 hours
1,589 gal./day/ft.^
2' longitudinal
1 cross
Sludge Pumps
Number Weirs
Weir Overflow Rate
Number Weirs
Length
AERATION BASINS
Number of Basins
2 (plunger type)
25,000 gal./day/LF
twin sets of 6/tank
8.25 ft.
6 Total
2 nitrification
4 aeration
Dimensions
Length
Depth
Width
303 ft.
16 ft.
30 ft.
Volume
Detention Time w/o
Recirculation
136,350 ft.
1,022,625 gal. each
545,400 ft.-* Total (4)
4,090,500 gals. Total (4)
4.91 hours
with 50% or 10 mgd
Recirculation
3.01 hours
Aeration
Number of Blowers
Diffusers
Rate O2 Transfer
FINAL CLARIFIER
Number
Dimensions
Diameter
Depth
Weir Length
7 w/total hp of 1650
2 piped to deliver 4
3 piped to deliver 4
@ constant speed
2 piped to deliver 4 or 8 psi @
@ variable speed
72 units (B-4 swing)
1.04 cfm/lb. BOD
4 units circular, centerfed
90 ft. .
11.08 ft.
1,130.4 ft.
psi 0 constant speed
or 8 psi
-40-
-------
Volume
Detention Time
Surface Loading
Overflow Rate
Return Sludge Pumping Station
Number
Minimum Ratings
Variable Capacities
Scum Removal
Number
Capacities
SLUDGE THICKENER
Primary Holding Tank
Dimension
Length
Width
Depth
Blowers
Sludge Withdrawal Pumps
Sludge Feed Pumps
Thickening Tanks
Dimension
Length
Width
Thickened Sludge Pumps
Pressure Water Pump Station
Number Supply Pumps
Number Return Pumps
SLUDGE DIGESTION
Digestion Tanks
Number
Old
New
Dimensions
Diameter
Depth
70,450 ft. each
528,390 gals, each
282,000 ft.3 Total
2,114,000 gals. Total
2.5 hours
786 gal./day/ft.
17,700 gal./day/ft.
6 (centrifugal)
4 activated sludge
1 feed nitrification tank
1 waste sludge
30-50 hp
1,500 - 2,400 gpm
2 (simplex plunger pumps)
2 hp @ 105 gpm
2 units
33.50 ft.
5.75 ft.
11.50 ft.
2 @ 240 CFM each
2 - 2 hp variable speed
@ 102 gpm
4-7.5 hp variable speed
4 units
70 ft.
18 ft.
2 - 7.5 hp duplex plungers
@ 225 gpm
3 turbine pumps, 15 hp @
1200 gpm
3-15 hp @ 1,400 gpm
4 units
2 each
2 each
80 ft. all units
26.5 ft. new units
24 ft. old units
-41-
-------
Volume Old
Volume New
Total Volume
Sludge Recirculation Pumps
Number
Sludge Transfer Pumps
Number
Macerating and Centrifuge
Feed Pumps
Number
SLUDGE DEWATERING
Centrifuges
Number
Capability of Dewater
Range of Dewatering
Capability (% solids)
Polymer System
Mixing Tank
Storage Tank
Pumps
Sludge Cake Conveyor
Belts
Capability
Chlorination
Chlorinators
Number
Capacities
140,900 ft.3
1,054,000 gals, each
151,600 ft.3
1,134,000 gals, each
585,000 ft. 3
4,379,000 gals.
4 units
2 old
2 new rated 350 gpm @ 15 hp
2 constant speed plungers
rated 235 gpm @ 10 hp
3 variable speed range 50 - 170
gpm @ 7.5 hp pump and 10 hp macerator
3 (bowl scroll type)
80 gpm
6-90
1 @ 1,500 gals.
1 @ 1,500 gals.
1 - Solution transfer rated 100
gpm @ 5 hp
3 - Chemical feed rate 16 gpm @
1.5 hp
24-ft. wide
9 tons/hour @ constant speed of 50 ft./min.
using a 0.5 hp reversible motor
4 units
3 vacuum operated
1 manually operated
2 @ 6,000 lbs./day
2 Q 2,000 lbs./day
-42-
------- |