EPA-R2-73-108
FEBRUARY 1973 Environmental Protection Technology Series
Treatment of Laundromat Wastes
Office of Research and Monitoring
U.S. Environmental Protection Agency
Washington, DC 20460
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and
Monitoring, Environmental Protection Agency, have
been grouped into five series. These five broad
categories were established to facilitate further
development and application of environmental
technology. Elimination of traditional grouping
was consciously planned to foster technology
transfer and a maximum interface in related
fields. The five series are;
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
H. Environmental Monitoring
5. Socioeconomic Environmental Studies
This report has been assigned to the ENVIRONMENTAL
PROTECTION TECHNOLOGY series. This series
describes research performed to develop and
demonstrate instrumentation, equipment and
methodology to repair or prevent environmental
degradation from point and non-point sources of
pollution. This work provides the new or improved
technology required for the control and treatment
of pollution sources to meet environmental quality
standards.
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EPA-R2-73-108
February 1973
TREATMENT OF LAUNDROMAT WASTES
By
Donald B. Aulenbach
Patrick C. Town
Martha Chilson
Project 12120 DOD
Project Officer
Richard Keppler
Environmental Protection Agency
John F. Kennedy Bldg.
Boston, Massachusetts 02203
Prepared for
OFFICE OF RESEARCH AND MONITORING
U.S. ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D.C. 20460
For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402
Prloe 95 cents domestic postpaid or 70 cents QPO Bookstore
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EPA Review Notice
This report has been reviewed by the Environmental
Protection Agency and approved for publication.
Approval does not signify that the contents necessarily
reflect the views and policies of the Environmental
Protection Agency, nor does mention of trade names or
commercial products constitute endorsement or recommenda-
tion for use.
ii
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ABSTRACT
Laboratory and field studies were conducted to evaluate the capabilities
of two commercially available laundromat waste treatment systems to
treat laundromat wastes with the possibility of recycling the treated
effluent. The Winfair Water Reclamation System (WWRS) involves the
addition of alum to a pH of 4, sedimentation, sand filtration, carbon
absorption, and passage through ion exchange resins. The American
Laundry Machinery Industries (ALMI) system employs chemical precipita-
tion prior to filtration through Diatomaceous Earth.
The WWRS achieved a 56% BOD reduction, 62% COD reduction, and 94% ABS
reduction, but suffered from a buildup of total solids in the effluent.
The system produced an effluent suitable for discharge into many streams,
For effluent recycling, a functioning demineral!zer would be required.
The ALMI system achieved a 63% BOD reduction, 69% COD reduction, 87%
ABS reduction, 94% PO^ reduction, and complete coliform removal. The
increase in effluent alkalinity and hardness render very questionable
the suitability of the effluent for reuse without softening and pH
adjustment. The use of the system would cost about 10C per wash.
This report was submitted in fulfillment of Project Number 12120 DOD
under the (partial) sponsorship of the Water Quality Office, Environ-
mental Protection Agency.
111
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CONTENTS
Section
I Conclusions
II Recommendations
III Introduction
Part I
IV Basic Laundry Waste Treatment Systems
V The Winfair Water Reclamation System
VI Laboratory Studies of Detergent Removal
VII Treatment System Operation
VIII Discussion of the Winfair System
Part II
IX The ALMI Filtration System
X Laboratory Analysis
XI Discussion of the ALMI System
XII Acknowledgements
XIII References
XIV Glossary
Page
1
3
5
7
13
17
25
35
37
43
59
61
63
65
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FIGURES
PAGE
1 LAUNDROMAT WASTE DISCHARGE 8
2 RANGE OF LAUNDROMAT WASTE WATER QUALITY 9
3 TYPICAL COMPOSITION OF DETERGENTS 10
4 WINFAIR WATER RECLAMATION SYSTEM 14
5 EFFICIENCY OF ALUM TREATMENT OF LAUNDROMAT WASTES 19
AT VARIOUS pH VALUES
6 EFFICIENCY OF VARIOUS ALUM DOSAGES FOR TREATMENT OF 22
LAUNDROMAT WASTES AT SEVERAL pH VALUES
7 EFFICIENCY OF VARIOUS ALUM DOSAGES FOR TREATMENT OF 24
LAUNDROMAT WASTES
8 SCHEMATIC FLOW DIAGRAM —AMERICAN LAUNDRY MACHINERY 26
INDUSTRY— DIATOMITE FILTRATION SYSTEM
9 LAUNDROMAT TREATMENT PLANT 27
10 DETERGENT CONCENTRATIONS THRUOUT WINFAIR SYSTEM 28
11 SUMMARY OF TOTAL DISSOLVED SOLIDS IN WINFAIR SYSTEM 33
12 ALMI WASTE WATER TREATMENT SYSTEM 38
13 SCHEMATIC FLOW DIAGRAM — ALMI -- DIATOMITE FILTRATION 39
SYSTEM
14 DIATOMITE FILTER FILTRATION CHARACTERISTICS 42
15 EFFLUENT TURBIDITY vs. pH IN THE ALMI SYSTEM 47
16 EFFECT OF CaCl DOSAGE ON TOTAL DISSOLVED SOLIDS IN 51
EFFLUENT FROM ALMI SYSTEM
17 EFFECT OF pH ON PO^ REMOVAL IN THE ALMI SYSTEM 53
18 EFFECT OF CaCl DOSAGE ON P04 REMOVAL IN THE ALMI SYSTEM 54
VI
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TABLES
1 Effect of pH on Alum Treatment of Laundromat Wastes 18
2 Effect of Various Concentrations of Alum at Different pH's 21
for Treatment of Laundromat Wastes
3 Effect of a Wide Range of Alum Concentrations for Treatment 23
of Laundromat Wastes
4 Summary of ABS Removal in Winfair System 29
5 Summary of Overall BOD and COD Removal in the Winfair 31
Reclamation System
6 Summary of pH Values in Winfair System 31
7 Summary of Total Dissolved Solids in Winfair System 32
8 American Laundry Machinery Industries Diatomaceous Earth 40
Filtration System
9 Summary of ABS Reduction with Various CaCl2 and Roccal 44
Additions
10 Summary of Removal of Alkyl Benzene Sulfonate in the ALMI 45
System
11 Summary of Reduction of Biochemical Oxygen Demand in the 45
ALMI System
12 Summary of Reduction of Chemical Oxygen Demand in the ALMI 46
System
13 Effluent Turbidity vs. Filter Aid 48
14 Summary of Changes in the Organic Nitrogen in the ALMI System 50
15 Summary of the Increase in Total Dissolved Solids in the 50
ALMI System
16 Summary of the Changes in Hardness in the ALMI System 52
17 Summary of PO^ Removal in the ALMI System 55
18 Summary of the Alkalinity in the Raw and Treated Waste 57
19 Summary of the Acidity in the Raw and Treated Waste 57
vii
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TABLES (CONT'D.)
No. Page_
20 Optimum Combination of Chemical and Mechanical Factors in 58
Removal of Pollutants and Pathogens from Laundromat Waste
Water in the ALMI Wastewater Treatment System
Vlll
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SECTION I
CONCLUSIONS
Part I
The Winfair Water Reclamation System was evaluated for its ability to
treat a laundromat waste for possible reuse. Alum added to achieve a
pH of 4-5 resulted in an effluent containing an average of 11 mg/1 ABS.
This is twice the level recommended for the detergent removal ion ex-
change resin. This will require replacing the resin twice as often as
specified.
The BOD reduction was in the order of 61%, and the COD reduction 71%.
This may be sufficient for discharge to many streams, and certainly
satisfactory for discharge to a subsurface disposal system.
The demineralizer system was absolutely non-functional. This will re-
sult in a build-up of'total solids if the effluent is reused. If the
effluent is to be discharged to waste, the demineralizer system is
not needed.
The system appears to operate satisfactorily without neutralization
before sedimentation. The average ABS reduction was 94%, having an
average residual of 2.3 mg/1.
With satisfactory operation of a demineralizer system, this effluent
could be reused at least once in a laundromat. Consideration of the
amount of make-up water to control the build-up of non-removed mater-
ials would have to be made. The system produces an effluent which
should be suitable for discharge into many streams.
Part II
The American Laundry Machinery Industries (ALMI) Diatomaceous Earth Fil-
tration System can be an effective system for laundromat waste treatment.
Under optimum operating conditions the System can achieve better than
98% ABS reduction, 94% P04 Deduction, 70% BOD reduction, and 84% COD
reduction. Coliforms can also be effectively removed.
A 98% or better removal of the ABS can be achieved with the addition of
24 mg/1 or greater of Roccal (a combination cationic detergent and germ-
icide). No apparent relation was observed between calcium chloride
addition and ABS removal, or between chemical addition and BOD or COD
reduction. In most cases the COD exceeded the BOD.
The total dissolved solids in the effluent was directly related to the
calcium chloride dose added. Thus to minimuze the increase in total
dissolved solids, a minimum amount of calcium chloride should be used
to effect treatment. The increase in total organic nitrogen due to
treatment was not significant.
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The turbidity of the effluent was directly related to the pH. At pH
values above 8 with the addition of NaOH the transmittance was always
greater than 95%. The transmittance dropped off sharply at pH values
below 7.
There was a general slight reduction in the hardness due to the treat-
ment; however, there are insufficient data to achieve a statistical
significance to this conclusion. Several data suggest that an excess
of CaCl2 increases the hardness in the effluent.
Increased CaCl2 dosage can result in an increased removal of phosphate.
However, more significantly an increase in pH results in a marked in-
crease in phosphate reduction with lower CaCl2 dosages. Pre-treatment
with alum followed by settling in the Winfair Water Reclamation System
(WWRS) prior to treatment in the ALMI system resulted in a high phos-
phate removal at a low CaCl2 dose.
The ALMI System meets most of the requirements for treatment of wastes
from coin-operated laundromats. The introduction of this system into
existent laundromats would increase the cost of washes by about 10t.
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SECTION II
RECOMMENDATIONS
Individual recommendations must be made on the basis of specific exist-
ing and potential uses of these treatment systems.
1. Treatment of laundromat wastes for discharge into the ground or to
a surface water.
Either system could be used for this degree of treatment. The ALMI
system is recommended due to ease of operation and greater reliability.
Additional studies could be made into the reason for the failure of
the demineralizer system in the WWRS.
2. Reuse of the treated effluent in the laundromat.
The WWRS was designed for reuse, whereas the ALMI system was not. Due
to the malfunction of the demineralizer system of the Winfair Water
Reclamation System (WWRS), the effluent from this system cannot be rec-
ommended for continuous reuse. Due to adverse conditions during opera-
tion of the American Laundry Machinery Industries (ALMI) system, no
determination of the buildup in total solids could be made. In order
to determine potential reuse, it is recommended that additional studies
be made at a location where at least partial reuse of the effluent could
be practiced.
3. Potential for phosphate removal.
In view of the use of alum in the WWRS and of calcium and potentially
ferric chloride or alum in the ALMI system, both these systems have a
potential for use in phosphate removal. It is recommended that addi-
tional studies be made of the use of these treatment systems for phos-
phate removal. (Note: This recommendation has already been carried
out as reported in a paper entitled "Phosphate Removal From Laundry
Waste Water" presented at the winter meeting of the New York Water
Pollution Control Association in New York, January 26, 1972.)
4. Application to treatment of other types of liquid wastes.
Since both treatment systems have been shown to be reasonably effective
in treating laundry wastes, they should also be effective in treating
normal domestic sewage, especially for phosphate removal. The systems
used in these studies could be used for small housing developments or
shopping centers. The principles could be expanded to serve larger
facilities. It is, therefore, recommended that studies be made to
determine the applicability of these systems to treat domestic sewage,
particularly for phosphate removal.
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SECTION III
INTRODUCTION
There are many diverse types of wastes which produce problems today.
One of these is the wastes from coin-operated laundromats, particularly
those located in areas where sewer systems are not accessible. Numer-
ous treatment systems have been devised for treating these wastes. Two
such systems became available and formed the conception of this study.
It is the purpose of this study to evaluate these two systems for the
treatment of laundromat wastes.
The post-World War II era gave rise to three developments which compli-
cated the laundry waste problem. First, was the mass production of
automatic home laundry equipment. Second, the building boom in suburban
areas placed much of this equipment in unsewered areas. Finally, the
appearance of coin-operated laundromats in these new suburban centers
meant that millions of gallons of detergent, germ, and soil-laden waste
water was being discharged into streams, estuaries, ponds and ground-
water supplies.
Since most of the early laundry detergents were not biodegradable, con-
ventional septic tank systems were ineffective in treating these wastes.
With the advent of biodegradable laundry detergents, some of the prob-
lems were ameliorated, but only if the coin-operated laundromats were
located in areas where there was a sufficient quantity of suitable land
for the construction of leaching fields. This was seldom the case since
most of these installations were in densely populated new suburbs "where
land was at a premium. Therefore, waste treatment facilities for coin-
operated laundromats in unsewered areas had to fulfill the following
requirements:
1) provide an effluent acceptable to health regulations
2) handle peak loads as well as normal demands
3) require a minimum of service and operational maintenance skills
and time
4) be able to be easily dismantled, transported and reassembled
at a new site
5) occupy a minimum of space
6) be economically feasible in terms of cost per load of wash, and
7) whenever possible, recycle the water for further use.
The first part of this report evaluates the Winfair Wastewater Reclama-
tion System (WWRS) which claims to fulfill all of the above requirements
This second part of the report describes the operation of the American
Laundry Machinery Industries (ALMI) wastewater treatment system, which
claims to fulfill all but the recycle requirement of laundromat waste
treatment system in unsewered areas, and evaluates the actual function
of that system.
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SECTION IV
BASIC LAUNDRY WASTE TREATMENT SYSTEMS
Wastes from both individual home laundries and multiple-unit coin-oper-
ated laundromats can present problems where they cannot be discharged
into sewerage systems provided with adequate treatment facilities. The
spread of population into unsewered areas is followed by the establish-
ment of coin-operated laundromats in these unsewered areas. An indica-
tion of the magnitude of the problem may be given by the estimate that
there are over 120 laundromats in Suffolk County, Long Island, New York,
alone^^). A summary of the amounts of wastes produced is shown in Fig.
1 and representative quality parameters are shown in Fig. 2. Nearly
all of these ultimately discharge their effluent into the ground. The
switch to the use of synthetic detergents (syndets) has also contributed
considerably to the problem. The conversion to linear alkyl benzene
sulfonates (LAS) (Fig. 3) has reduced this problem where aerobic biolog-
ical treatment is provided. However, under anaerobic conditions, such
as in septic tanks and saturated soil, there is little breakdown of the
LAS. In saturated soils, these syndets may travel considerable distances
without being decomposed, thereby entering water supplies. In addition,
studies on Long Island'"^ have shown that the synthetic detergents seem
to cause other pollutional material, specifically coliforms, to be car-
ried greater distances than conventional soaps do. This is in partial
disagreement with work done by Robeck, et al. who showed that in-
creased concentrations of ABS had no effect upon the travel distance of
coliforms in water-saturated, sandy soils under laboratory conditions.
The problems created by laundromat wastes have led to many studies of
methods for treatment, and to the creation of numerous waste treatment
systems. A large volume of work was done at Manhattan College for the
State of New York^5^. Work was done to determine the amount of alum
needed to improve the quality of the waste (with no consideration of
ABS removal), and further, the amount of powdered activated carbon
needed to remove the ABS. An alum dose of 100 grains/gallon (1700 mg/l)
and an activated carbon concentration 7 times the ABS concentration are
recommended to remove substantially all anionic syndets. Close scrutiny
of the data reveals that the optimum conditions for clarification of the
waste without regard to ABS'removal are 1530 mg/l of alum at pH 5.7,
with the ranges being 850 - 2210 mg/l alum and pH 5.1 6.0. A dose of
1360 mg/l of alum and 340 mg/l powdered activated carbon at pH 6.0 pro-
duced an effluent containing 1.8 mg/l ABS. No studies were made to de-
termine the removal of ABS by alum alone.
Flynn and Andres recommended treatment with alum at pH 4.0 and pow-
dered activated carbon to be effective in treating laundromat wastes.
Rosenthal, et al. ^) conducted a more thorough study of laundromat waste
treatment using alum and activated carbon. They found that 800 mg/l of
alum alone at pH 4.5 removed 77 percent of the ABS. The acceptable pH
range was 4.3 4.6. In the laboratory, 2000 mg/l powdered activated
carbon (Nuchar) increased the ABS removal to 97 percent. In an actual
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00
FIGURE 1
LAUNDROMAT WASTE DISCHARGE*
Avg. Total Water Discharge/Laundromat 1.25 x 10 gal./yr.
Avg. Pounds Detergent/Laundromat _
(and other compounds) "
Avg. Wastewater Flow/Machine 89-240 GPD
Maximum Avg. Flow/Machine . 587 GPD
Minimum Design Basis for Treatment C[-A , , , .
/•Tr, v. -i \ 550 gal./machine
(12 hour day) &
* 120 Launderettes - Suffolk Co., New York (1963)
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FIGURE 2
TYPICAL LAUNDERETTE WASTE
(4)
1
Substance
ABS
Suspended Solids
Dissolved Solids
COD
Alkalinity
Chlorides
Phosphates
pH
Nitrates
Free Ammonia
Sulfates
Range (mg/1)
Minimum Average
3.0 44.0
15.0 173.0
104.0 812.0
65.0 447.0
61.0 182.0
52.0 57.0
1.4 148.0
5.1
< 1.0
3.0
200.0
Maximum
126.0
784.0
2,064.0
1,405.0
398.0
185.0
430.0
10.0
-
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FIGURE 3
TYPICAL COMPOSITION OF DETERGENTS
DETERGENTS CH,
i°
ABS NaS0 <>CH ..... CH- C-CH
CH
3 2 ..... 2- -3
LAS CH3-CH2 ..... CH -CH2 ..... COOH
0
o
S-ONa
COMPOSITION OF DETERGENTS _%_
SURFACTIVES I0~30
AMIDE FOAM STABILIZERS 3-6
POLYPHOSPHATES 25 - 4O
SILICATES 5-7
CARBOXY METHYL CELLULOSE OR ,n
(SOIL SUSPENSION) Ut5~ LO
SODIUM SULFATE 15 - 25
WATER 6-15
10
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laundromat, alum plus 400 mg/1 powdered activated carbon resulted in
83 percent removal of the ABS. The use of granular carbon in a series
of three filters instead of powdered carbon increased the ABS removal
to 99 percent in the laboratory and 93 percent in the plant. Further
studies showed that alum coagulation at pH 11.4 with lime produced a
clearer effluent which settled more rapidly and used less alum to achieve
the same ABS reduction. Passing the alum-lime effluent through a 10 foot
deep granular activated carbon pressure filter produced a 99.8 percent
reduction in ABS in the laundromat waste treatment plant. Paulson *-5'
used granular activated carbon to remove syndets from filtered sewage
plant effluents. He applied the effluent to 4 - 5 foot units in series
at 10 gpm/ft2, and regenerated the first unit when the ABS in the efflu-
ent reached 0.5 mg/1. Weber'-1-0' determined that the ABS uptake by gran-
ular activated carbon increased with decreasing pH.
The basic types of laundry waste treatment systems have been studied by
Flynn and Andres^'. Their conclusion is that those employing alum at
a pH of about 4.0 and powdered activated carbon produce the greatest re-
duction of ABS at the most reasonable cost in operation time, equipment
and chemicals.
11
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SECTION V
THE WINFAIR WATER RECLAMATION SYSTEM
A proprietory treatment plant utilizing the basic treatment principles
of Flynn and Andres, that of employing alum at a pH of about 4.0 and
powdered activated carbon^ , is manufactured by the Winfair Corporation,
Green Lake, Wisconsin (now a subsidiary of the Oshkosh Filter Company,
Oshkosh, Wisconsin). A complete Winfair Water Reclamation System was
installed at the Coin-Op Laundry at Burnt Hills, New York. This is a
small community north of Schenectady, where individual wells and waste
treatment systems are the only means available to obtain water and dis-
pose of liquid wastes, respectively. The ground water table in the
immediate area surrounding the laundromat is near the surface, and is
used as a water supply by some neighbors. Water about 70 feet below
the surface is highly sulfurous and has a total dissolved solids content
of around 700 mg/1. Permission could not be granted to dispose of the
untreated laundromat waste in a septic tank system. The problems of
water supply and disposal were both overcome by the installation of this
complete water reclamation system.
In this system (Fig. 4) the washer effluents are first screened and then
stored in a holding tank. From here a 15 gpm pump conveys the waste
through the alum coagulation system. Alum is added to pH 4.2 4.5 and
then the waste enters a 45 gallon upflow tank for floe formation (3 min.
contact time). The effluent from this tank is treated with lye so that
the pH after settling is 7.0 (pH slightly higher than 7.0 at the test
point). The waste now travels through 3/4 inch copper tubing to the
mid-depth of a large settling tank. The sludge is disposed of periodi-
cally and the clear supernatant is pumped through 1 of 5 pressure sand
filters in parallel (3 gpm through each). The sand filter effluent
passes up through a bed containing Duolite (Diamond Alkali Company,
Redwood City, California) anion exchange resin A 102 D for detergent re-
moval. After removal of the detergent, the waste passes up through a
bed of granular activated carbon for taste, odor, and color removal.
From there, 1/3 of the flow passes through a cation and an anion exchange
resin for complete deionization. After recombination, the waste is
chlorinated and the pH neutralized before it enters the clean water tank
prior to reuse.
It appears that such a system should provide a satisfactory water for
reuse in a laundromat. It is claimed that the cost of the additional
treatment is offset by the saving of fresh water and reheating of the
water, since it is normally still warm after passing through this treat-
ment system. However, some difficulty was encountered after the system
had been operating for several months. The detergent removal resin be-
came saturated, and no longer functioned in its capacity to remove de-
tergents. This resin cannot be regenerated by ordinary means and must
be returned to the manufacturer for regeneration. Also, the two deion-
izer resins were entirely ineffective, causing the total solids in the
13
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FRcfM
HOLDING
TANK
CHEMICAL
FEED
COAGULATION
TANK
3min.
pH
CONTROL
TO
DISCHARGE
SETTLING TANK
1000 GAL.
CHLORINE
I
L
CATION
EXCHANGE
SUPERNATA^J
ANION
EXCHANGE
A A'A A A
I T Tr T 1
SAND
1
F
ILTERS
\
ACTIVATED
CARBON
ANION
ABS
EXCHANGE
RESIN
FIGURE 4-WINFAIR WATER RECLAMATION SYSTEM
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recirculating water to increase constantly. These resins are normally
regenerated weekly by conventional acid and alkali techniques. Efforts
to rejuvenate them proved fruitless, and the total solids continued to
increase.
The reason for the failure of the detergent removal resin was quite ap-
parent. This resin was designed to function on the basis of an effluent
from the alum coagulation system containing 5 mg/1 of ABS or less. By
test, the alum treatment effluent contained approximately 15 mg/1 ABS.
Thus, the resin became saturated in 1/3 the expected time. Replacement
of this resin produced an effluent containing only 2 mg/1 ABS after com-
plete treatment. Further, the anion exchange resin in the deionizer
would attempt to remove a portion of the residual detergent not removed
by the other portions of the system. During the period when the deter-
gent removal resin was saturated, a high detergent concentration reached
the anion demineralizer where it was exchanged into the resin. Since
the detergent cannot be removed from the resin by conventional means,
this resin became saturated with the detergent and no longer functioned
as an anion remover. No similar analogy can be made for the reason the
cation exchange resin failed.
The major portion of the problem appeared to be the failure to achieve
the expected ABS removal in the alum coagulation system. Whereas it
was expected that this system should produce an effluent containing
5 mg/1 of ABS or less, the actual effluent contained around 15 mg/1
ABS, or a removal, in the order of 50 percent. Since the work done at
Manhattan College did not include an evaluation of the removal of
ABS by alum alone, and the work done by Rosenthal et al. °' showed
77 percent removal of ABS by alum alone at pH 4.5, it was felt that
further studies to determine the removal of detergent by alum coagula-
tion alone were needed to evaluate the problem.
15
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SECTION VI
LABORATORY STUDIES OF DETERGENT REMOVAL
Three series of experiments were performed to study the removal of deter-
gents by the use of various concentrations of alum at various pH values.
All mixing and coagulation were done using a typical 6-place multiple
laboratory stirrer. Inasmuch as possible, an attempt was made to have
the laboratory procedures reproduce the treatment provided by the Winfair
Water Reclamation System. After adding alum, the samples were mixed at
50 rpm for 3 minutes. Then the pH was adjusted to the appropriate value,
and coagulation was produced by stirring at 30 rpm for 10 minutes, after
which the samples were allowed to settle for 30 minutes. Determinations
were made for ABS to determine the detergent removal, and for chemical
oxygen demand and turbidity to determine the quality improvement. The
sludge volume after settling was also determined in order to provide
some additional information on the amount of sludge storage capacity
needed. ABS was determined by the methylene blue extraction technique,
using 2 ml of sample. This volume of sample did not tend to produce
emulsions during the extraction. All other analyses were made according
to Standard Methods^9\
The waste samples were secured from the holding tank containing the
mixed laundromat wastes. The only pre-treatment it received was screen-
ing to remove lint and other large particles. The temperature of the
waste at the time of sampling was 40°C.
In the first test, sufficient alum was added to a portion of the waste
sample to lower the pH to 4.5. This same amount of alum was then added
to four other samples; a control containing no alum was given the same
physical treatment. After mixing for 3 minutes, the pH of the samples
containing alum was adjusted with acid or sodium carbonate as needed to
values of 3.5, 4.5, 5.5, 6.5, and 7.5. No pH adjustment was made in the
control. The results are summarized in Table 1, and the reductions in
ABS, COD, and turbidity are shown in Fig. 5.
The best reductions in ABS and COD occurred at pH 4.5, whereas the best
turbidity reduction occurred at pH 7.5. Actually the turbidity reduc-
tion was good throughout the entire pH range. The lowest sludge volume
occurred at pH 3.5, although the amount of sludge produced at pH 4.5
was still quite low. The high total solids content of the waste reflects
the failure of the deionizer in the treatment system. Also to be noted
is that the alum treatment resulted in an increase in the total solids
content of about 1,000 mg/1. The results from the control containing no
added alum showed no ABS removal, and a slight increase in turbidity.
The reduction in the COD of the control is likely due to sedimentation
of larger particles. There was some sediment on the bottom of this con-
tainer, but it was insufficient to measure on the percent scale. It is
apparent that all the ABS reduction in the test samples was due to the
added alum, and not due to plain sedimentation.
17
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TABLE 1
EFFECT OF pH ON ALUM TREATMENT OF LAUNDROMAT WASTES
00
Sample
Alum Cone, mg/1
PH
H2 SO^ Cone, mg/1
Na0 CO Cone, mg/1
t- O
pH Before Settling
Final pH
ABS, mg/1
COD, mg/1
Turbidity, mg/1
Sludge Volume, %
Temperature, °C
- >
Total Solids, mg/1
Waste 1
1500
7.25 4.5
0.13
0
3.. 5
3.9
32.1 22
699 296
125 1
3.7
22
9,0'76 ' 13,364 '
2
1500
4.6
0
- o
4.5
4.5
13.6
285
5.5
8
-
10,176
3
1500
4.6
0
455
5.5
5.6
15.2
285
1
40
-
10,046
4
1500
4.6
0
740
6.5
6.6
17.6
293
0.8
24
-
10,116
5
1500
4.6
0
1150
7.5
7.5
17.9
300
0.5
28
-
10,376
6
0
7.25
-0
0
-
7.3
32.9
551
140
- 0
-
9,392';..
-------
FIGURE 5
EFFICIENCY OF ALUM TREATMENT
OF LAUNDROMAT WASTES AT
VARIOUS pH VALUES
O
100
90
80
70
60
I-
o
Q 50
LU
o:
40
30
20
10
••cr-
TURBIDITY
COD
XUUL
3.5. 4.0 45 5.0 5.5 6.0 6.5 7.0 75
FINAL pH
19
-------
In an attempt to determine if satisfactory results could be obtained at
any lower alum dosages, a second experiment was run adding 1,000, 1,250
and 1,500 mg/1 alum. Further, in order to evaluate the recommended oper-
ation of the Winfair treatment system in which the alum treated mixture
is neutraJized to pH 7.0 before sedimentation, duplicate samples were
run: 1 with no pH adjustment, and the other adjusted to pH 7.0 with
sodium carbonate after 3 minutes mixing at 50 rpm and before 10 minute
coagulation at 30 rpm. The results are summarized in Table 2, and the
reduction in ABS, COD, and turbidity for the unneutralized and the neu-
tralized samples are compared in Fig. 6. The pH was similar with all 3
alum dosages. The ABS removal without pH adjustment was consistently
near 60 percent over the range of alum additions, whereas in the samples
adjusted to pH 7.0, the greatest ABS reduction was about 50 percent with
1,000 mg/1 alum, and this reduction dropped to 40 percent with 1,500 mg/1
alum. Neither the alum concentration nor the pH in the ranges covered
had any significant effect upon the COD removal. The turbidity removal
was poor with 1,250 and 1,500 mg/1 of alum without pH control, but at
pH 7.0 the turbidity removal was nearly constant at 90 percent. At all
alum dosages used, the sludge volume without pH adjustment was about 1/3
that at pH 7.0.
Since the previous experiments indicated better ABS removal with no pH
neutralization, but covered only a narrow range of alum dosages, the
next logical step seemed to be to study the effects of a wide range of
alum dosages with no pH neutralization. Alum was added to samples of
the waste in 250 mg/1 increments from 500 to 1,750 mg/1. No attempt was
made to maintain the pH near 4.5. Mixing and coagulation were maintained
as in the previous experiments. The results are summarized in Table 3,
and the efficiencies of removal of the ABS, COD, and turbidity are shown
in Fig. 7. The addition of 500 mg/1 alum lowered the pH to only 5.5
whereas the addition of 750 mg/1 and greater lowered the pH to nearly
4.5 and even slightly below this level with 1,750 mg/1 alum. The maxi-
mum ABS removal of 67 percent occurred with the addition of 1,000 mg/1
alum, and only slightly less removal occurred in the range of 750 to.
1,250 mg/1 alum. Poor ABS removal occurred with only 500 mg/1 of alum,
and again with 1,500 mg/1, but increased removal again occurred with
1,750 mg/1 alum. The COD removal was fairly consistent above 750 mg/1
alum, but was somewhat less with only 500 mg/1. The best turbidity
removals occurred between 750 and 1,250 mg/1 alum. There was no sig-
nificant difference in the sludge volumes produced with the various alum
additions. The total solids generally show the effect of the added alum,
but there appeared to be a slight reduction in total solids with the
addition of 500 and 750 mg/1 alum. Generally, it appears that optimum
conditions for ABS, COD and turbidity removal are 750 to 1,250 mg/1 alum
in the pH range of 4.5 to 4.8.
An important observation of these lab studies is that the lowest ABS con-
centration achieved for any procedure was in the order of 10 mg/1. This
is twice the value claimed by the manufacturer, and upon which "the ABS
removal resin is based. This means simply that the resin will be satu-
rated in half the predicted time, or to put it another way, the cost for
the ABS removal by the resin will be twice that predicted by the manufac-
turer.
20
-------
TABLE 2
EFFECT OF VARIOUS CONCENTRATIONS OF ALUM AT
DIFFERENT pH'.S FOR TREATMENT OF LAUNDROMAT WASTES
Sample^
Alum Cone, mg/1
Na0 CO Cone, mg/1
£. d
pH Before Settling
Final pH
ABS, mg/1
COD, mg/1
Turbidity, mg/1
Sludge Volume, %
Temperature, °C 20
Raw
Waste
-
-
7.1
-
38.7
625
128
_
1
1000
0
4.7
4.6
16.8
382
15
9.5
2
1000
560
7.0
6.9
19.6
400
3.9
22.2
3
1250
0
4.6
4.6
15.6
382
52
8.7
4
1250
780
7.0
7.1
21.6
385
4.6
28.5
5
1500
0
4.6
4.5
15.9
385
76
8.2
6
1 1
1500
925
7.0
7.0
23.5
389
5.4
26
-------
FIGURE 6
EFFICIENCY OF VARIOUS ALUM DOSAGES
FOR TREATMENT OF LAUNDROMAT
WASTES AT SEVERAL pH VALVES
2
p
o
—V
—}
Q
\
\
\
\ <^
^^x^-ABS
^ ^^N^
° r° a ^~*i ^
^COD °" ^COD
-
-
-
iii iii
1,000 l£50 1,500 1,000 1,250 1,500
ALUM CONCENTRATION mg/l
22
-------
TABLE 3
EFFECT OF A WIDE RANGE OF ALUM CONCENTRATIONS
FOR TREATMENT OF LAUNDROMAT WASTES
CO
Sample
one. mg/1
pH _
'g/1
ig/1
ity, mg/1
Volume, %
Raw
Waste
-
7.2
33.2
585
135
_
1
500
5.5
23.5
358
65
9
2
750
4.8
12.3
314
7
13.2
3
1000
4.7
10.8
307
8
12
4
1250
4.5
14.9
307
15
10
5
1500
4.5
18.3
314
60
10
6
1750
4.4
14 .4
314
90
7.5
Final pH
ABS, rag/
COD, mg/
Turbidit;
Sludge V
Temperature, °C
21
Total Solids, mg/1
9,334
9,118 9,132 9,316 9,478
9,670 9,862
-------
FIGURE 7
EFFICIENCY OF VARIOUS ALUM DOSAGES
FOR TREATMENT OF LAUNDROMAT WASTES
100
90
80
70
o 60
o
Q
LU
CC
50
40
30
20
10
0
5.5
TURBIDITY
4.8 4.7 4.5 4.5
PH
ABS
4.4
0 500 750 IpOO 1,250 1,500 1,750
ALUM CONCENTRATION mg/l
-------
SECTION VII
TREATMENT SYSTEM OPERATION
The above studies were performed under the auspices of the New York
State Health Department, and showed the need for a more thorough study
of the system. Meanwhile, the laundromat operator had to discontinue
use of the Winfair system due to complaints by customers of odors and
foaming in the recycled water. In an effort to alleviate the problem,
he purchased and put into use a treatment system designed by American
Laundry Machinery Industries. This system is based upon the precipi-
tation of the anionic syndets by means of a cationic syndet, the pre-
cipitation of phosphates and other materials with CaCl_, and separating
the solids by means of a pressure diatomaceous earth filter (Fig. 8).
Whereas this provided satisfactory treatment of the waste, it did not
solve the problem of water supply nor the hydraulic discharge of the
treated effluent. Thus, the operator was forced to discontinue his
laundromat operation at Burnt Hills.
However, the operator retained the 2 treatment systems and offered their
use for research purposes. When a Federal Water Pollution Control Admin-
istration Grant became available, he graciously offfered their use at
another laundromat. They were set up in a shed which was somewhat re-
modelled and electrified. The flow diagram is shown in Fig. 9. A 4,000
gal. holding tank was installed and four 1,000 gal. tanks were provided
for settling, sludge holding, and treated water. Chlorination was ap-
plied in the treated water storage tank. The system was designed so
that the waste would flow into the holding tank, and when it was full,
the waste would overflow into the existing distribution boxes and tile
drainage field. Physical problems were encountered with these last two
appurtenances, in that trucks delivering to the adjacent food market
would drive over them, crushing them and blocking them. This resulted
in the overflow of raw wastes from our holding tank.
The Winfair system was set up and put into operation first while re-
placements were awaited for the filtering elements for the ALMI system
which were found to be rusted beyond use upon receipt of the units.
The Winfair system was operated for a period of 9 months. Analyses
were performed for ABS, COD, BOD, pH, and total dissolved solids.
The ABS concentration throughout the system is shown in Fig. 10. The
actual values are summarized in Table 4. The greatest removal of ABS
was accomplished by the alum addition followed by sedimentation. This
was in the order of 76% of the initial ABS, and resulted in an average
ABS, after settling, of slightly over 11 mg/1. This is in the same
order as the laboratory experiments. The sand filter removed a little
more ABS, but the detergent removal resin lowered the ABS to an average
of less than 3 mg/1. This resin actually removed in the order of 70%
of the remaining ABS. The activated carbon and the demineralizer system
removed little additional ABS. The average overall ABS removal was 94%.
25
-------
TO CHLORI NATION,
AND DISCHARGE
TRANSFER
PUMP
PRECOAT
FLOAT
CONTROIL
i-CHEMICALS
PUMP t
CHEMICAL
TANK
FILTER
PUMP
FLOAT
CONTROL
y
r
Ln
1
HOLDING TANK
No. I
FILTER
4-tX-
SLUD
PUMP
RAW WATER
"FROM WASHER
No.2
FILTER
TO SLUDGE
HOLDING TANK
VALVE SETTINGS
PRECOAT ON STREAM DESLUDGE
OPEN 1,2,3,6,7,8 1,2,3,6,7 4,5,6,7
CLOSED 4,5 4,5,8 1,2,3,8
FIGURE 8
SCHEMATIC FLOW DIAGRAM-AMERICAN LAUNDRY
MACHINERY INDUSTRY-DIATOMITE FILTRATION SYSTEM
-------
J3S' TO LAUNDROMAT
25'
HOLDING
TANK
4,000 GALS.
0 o
ALMI
SYSTEM
WINFAIR
40'
CLEAN WATEF
8 CHLOR-
INATION
1,000 GALS.
ALL 1,000 GAL. TANKS
APPROXIMATELY 6'x4x7'DEEP
60' TO
DISCHARGE
FIGURE 9
LAUNDROMAT TREATMENT PLANT
SYSTEM
-------
100
10
CO
m
0.1
1440
109.0
FIGURE 10
DETERGENT CONCENTRATIONS
THRUOUT WINFAIR SYSTEM
EACH DOT OR CIRCLE
- REPRESENTS 1 ANALYSIS
^ LINE CONNECTS AVG. VALUES
o
QjU.
O
m
oc
a:
LJ
N
<
oc.
1-UJ
UJ
en
QUJ
1
ou.
(TUJ
UJ
UJ
Q
28
-------
TABLE 4
SUMMARY OF ABS REMOVAL IN WINFAIR SYSTEM
ID
Unit
Raw Waste
Settling Tank
Sand Filter
Detergent Removal
Activated Carbon
Detnineralizer
Number
of
Samples
75
67
67
68
68
74
Max.
144.0
31.5
27.0
4.7
3.8
4.4
ABS, mg/1
Min.
21.5
2.5
4.6
1.4
0.54
0.08
Avg.
47.15
11.25
9.69
2.86
2.61
2.31
Avg.
% of
Original
76
3
14
0.5
0.6
Reduction
> % of
Remaining
76
13
70
8
11
Overall
94.1
-------
The BOD and COD results are summarized in Table 5. These parameters
were determined to show the effectiveness of this system as a treatment
system. If the effluent is to be recycled, these parameters must be
followed in order to be alerted to an undesirable build-up. If the
effluent is to be discharged, their concentrations must be known in
order to determine if the effluent will be acceptable in the receiving
body of water. The average BOD of the effluent was 52 mg/1 and the
average BOD reduction was in the order of 56%. The average COD of the
effluent was 114 mg/1 and the average COD reduction was 62%.
The pH (Table 6) of the raw waste was generally near neutral to slightly
alkaline. On only two occasions was the pH below 6.8. These are con-
sidered due to the production of septic conditions in the holding tank.
The pH adjustment in the flocculating tank was maintained between 3.9
and 5.1 with one value at 6.0. The pH increased more than one unit on
an average as it passed through the settling tank. By the time it
reached the end of the treatment system it reached an average value
great er than 6.0.
The total dissolved solids pose a problem if the effluent is to be reused
in a laundromat. The dissolved solids through each unit of the system
are summarized in Table 7. The variation was greatest in the raw waste
which had a minimum value of 625 mg/1 and a maximum of 1,4-50 mg/1. The
primary concern is that the overall system resulted in an increase of
total dissolved solids, rather than the desired reduction. This is shown
in Fig. 11. The greatest increase was due to the alum addition, and was
in the order of 20 mg/1. The demineralizer, which was designed to reduce
the dissolved solids, resulted in an average increase of 6 mg/1, or essen-
tially no effective reduction.
The effluent from the system was chlorinated in the final holding tank
before being discharged to a swampy area of a slow-running stream. This
stream was little more than a drainage ditch which helped to drain the
high water table of the surrounding area. All the houses in the area
are provided with septic tank and tile field systems. The overflow from
the holding tank (as described previously) also reached this swampy area.
During warm weather an offensive odor arose from the stagnant stream,
causing complaints by the neighbors. An injunction was brought against
the laundromat operator to prevent the overflow of wastes from the hold-
ing tank. It was decided to install a float valve on the holding tank
so the system would operate automatically when the holding tank was full.
Even with the promise to have the float valve operative within a week's
time, the judge closed the laundromat. This also resulted in the land
owner's filling in the swamp and digging a channel to carry off the
water, thereby eliminating the problem created by the stagnant water.
Whereas the injunction closed the laundromat, there was no claim against
the operation of the treatment system. Arrangements were made to trans-
fer 2,000 gal./day of laundromat waste from another laundromat about 3
miles away. This allowed operation of the treatment system without mov-
ing the equipment. However, no further studies were performed using the
Winfair system.
30
-------
TABLE 5
SUMMARY OF OVERALL BOD AND COD REMOVAL
IN THE WINFAIR WATER RECLAMATION SYSTEM
No. of Influent mg/1 Effluent mg/1 Average %
Parameter Samples Max. M_in._. Ayg._ Max. Min. Avg^ Reduction
BOD 101 185 50 119.2 118 20.5 52.2 56.4
COD 70 438 136 293.4 244 38 113.8 62.1
TABLE 6
SUMMARY OF pH VALUES IN WINFAIR SYSTEM
Unit
Raw Waste
Flocculation Tank
c -
Settling Tank
Sand Filter
Detergent Removal
Activated Carbon
Demineralizer
No. of
Samples
134
136
117
117
117
117
134
Ma?c.
7.6
6.0
6.7
6.7
7.0
6.9
6.8
Min.
5.0
3.9
4.2
4.5
5.0
5.2
5.1
Avg.
7.13
4.45
5.58
5.76
5.95
5.99
6.07
31
-------
TABLE 7
SUMMARY OF TOTAL DISSOLVED SOLIDS IN WINFAIR SYSTEM
Unit
Raw Waste
Settling Tank Eff.
Sand Filter Eff.
Detergent Removal Eff.
Activated Carbon Eff.
Demineralizer Eff.
Number
of Samples
81
79
79
79
79
81 -
Total Dissolved Solids, mg/1
Max.
1,450
1,425
1,400
1,375
1,410
1,325
Min.
625
750
700
690
700
750
Avg.
931
952
953
956
968
974
-------
FIGURE II
SUMMARY OF TOTAL DISSOLVED SOLIDS
IN WINFAIR SYSTEM - mg/1
980 r
970
960
E950
CO
o
_l
o
00 940
o
930
^920
910
900
890
O
o
UJ
LU
cr
QUJ
CO
C9
UJUJ
oo:
a:
ut
a:
LU
o<
-------
SECTION VIII
DISCUSSION OF THE WINFAIR SYSTEM
The Winfair Water Reclamation System was operated for a period of nine
months adjusting the pH of the raw waste with alum in the range of 4.0
to 5.0, but with no neutralization prior to sedimentation. The average
ABS content after settling was 11 mg/1, which correlates well with the
results of the lab studies. The value is double that which the manufac-
turer claims can be expected from this portion of the system. However,
it is less than the 15 mg/1 obtained by the original operator. It does
confirm that the anion ABS exchange resin will be depleted in half the
time predicted by the manufacturer. So long as consideration is made
for this, it will not create a serious problem except for an increase
in cost for the operation. The overall ABS reduction was 94%, result-
ing in a residual ABS of 2.3 mg/1. This is greater than the recommended
drinking water standards but should be satisfactory for reuse in a
laundromat.
The BOD and COD removals are intermediate between primary and secondary
treatment. The residual may or may not be acceptable for discharge
depending upon the receiving stream. This would also depend on the
volume of the waste from each individual laundromat under consideration.
Generally speaking, the average BOD of 52 and the average COD of 114 in
the effluent are considered rather high for recycling of the effluent.
Chlorination may reduce these slightly and also prevent septic condi-
tions in the recycle holding tank.
pH was to have been an important key in this study. Since the initial
pH adjustment was difficult to establish, it was expected that a wide
range of pH values would be obtained allowing for an evaluation of the
degree of treatment over a wide pH range. Instead, the lab assistants
went to extreme pains to maintain the pH between 4.0 and 5.0 in order
to obtain what the laboratory studies had shown to be the pH for the
greatest purification. An attempt was made to correlate the pH vs
treatment, but the results showed no conclusive trend. It is inter-
esting to note that when the system was first set up and operated to
get the bugs out, on one occasion the pH in the flocculation tank was
6.0, and the ABS in the effluent was recorded as 0.0. Since this was
a break-in period both from the standpoint of operating the system and
perfecting lab techniques, no great value can be placed on this single
result.
One of the greatest disappointments was the operation of the demineral-
izer system for removal of the total dissolved solids. The increase in
the total dissolved solids due to the addition of the alum of about
20 mg/1 was less than that of up to 1,000 mg/1 experienced in the lab
studies. This indicates better control and separation in the system
than in the lab. The increases in passing through the remaining units
of the system are insignificant. However, when it comes to the deminer-
alization, this is supposed to reduce the total solids, not result in an
35
-------
insignificant increase. When the system was started up, fresh resins
were placed in the units. Some difficulty was found in balancing the
valves so that approximately one-third of the flow passed through the
demineralizers. After this was established samples were secured for
the dissolved solids test which showed no reduction. It is possible
that in establishing the flow, the resins became exhausted. Therefore,
they were regenerated as per specifications, but with no change in
results. Numerous efforts were made to regenerate the resin and they
were completely replaced later in the study. The flow was regulated
to all extremes including passing all the liquid through the resins.
All of these efforts proved fruitless. It can only be concluded that
the demineralizer system provided by the company was not capable of
performing the job for which it was designed. This is the same con-
clusion reached with the initial evaluation of the failure of the sys-
tem in its first location.
Although the possibility of reuse of the treated effluent was considered,
it was not attempted in any of these studies. The water supply for the
laundromat was adequate, and it was felt that the existing good quality
water would be preferred to reused water. The only advantage that could
have been gained by reuse would have been a saving in waste water that
would have had to be discharged. The quality of the effluent is con-
sidered to be adequate for reuse in a laundromat, but certainly not for
drinking. No consideration could be made of the number of reuse cycles
that could have been made before the build-up of non-removed materials
would reach an undesirable level.
It is also considered that this treatment would result in an effluent
which could be discharged into a subsurface disposal system with a min-
imum of problems.
36
-------
SECTION IX
THE ALMI FILTRATION SYSTEM
As early as 1944, the U.S. Army Corps of Engineers developed a diatomite
filtration unit for use in supplying safe and potable water for field
troops^-1'. These units had to (a) be portable and (b) operate at a
high rate of output. Since the nation was then involved in a global
war, the economic factor was not of great import in evaluating the over-
all success of the system. In addition to the conventional health and
aesthetic requirements, the system had to remove the cysts of Endamoeba
histolytica and the cercaria of schistosomes. This was particularly
crucial in both the South Pacific and the Mediterranean Theatres of war.
At flow rates of 6 to 12 gpm psf, many cysts passed through conventional
sand type filtration units. On the other hand, the diatomite filters
affected virtually complete removal of cysts under the most severe tests.
These findings were again utilized as the post World War II boom of home
laundries and public laundromats spread into unsewered areas, increasing
the need for effective treatment units. The American Laundry Machinery
Industries (ALMI) Diatomaceous Earth Filtration System was developed for
such laundry waste treatment.
Structually, the ALMI wastewater treatment system (WWTS) used is a con-
tinual water filtration system consisting of a mixing tank, 2 chemical
feed tanks, 2 pressure filter units operated in parallel, and the appro-
priate pumps, valves, and connecting piping. Additional appurtenances
include a :4,000 gal." raw wastewater holding tank to provide flow equal-
ization, a 1,000 gal. treated water tank which served as a chlorine
contact tank, and a 1,000 gal. sludge holding tank which retained the
filtered materials plus the spent diatomaceous earth (DE) until hauled
away by a scavenger. Each filter unit contains 45 vertical mesh screen
tubular elements (total of 90 elements) which serve as a septum for the
diatomaceous earth (DE) precoat. Figure 12 shows an 8,000 GPD system.
A schematic flow diagram is shown in Figure 13. The principal charac-
teristics of this unit are listed in Table 8.
System operation consists of applying a precoat on the filter elements
by recirculating a water suspension of DE from the mixing tank through
the filters with return to the mixing tank. The precoat operation usu-
ally requires 3-6 min. using a 45 Ib. change of diatomaceous earth.
Following precoating, the waste purification cycle is intitiated by
pumping wastewater from the holding tank to the mixing tank, through
the filters and to the treated water tank. A purification cycle nor-
mally lasts 15 minutes during which 400 gallons of wastewater are proc-
essed at a flow rate of 25 GPM. Following each 15 minute filtration
cycle, a timer switch shuts off the filter pumps and activates a mechan-
ical shaker mechanism which "bumps" off the precoat from the filter ele-
ments. The precoat and filtration cycles are then repeated following
completion of the bump phase. The periodic bump to remove and re-precoat
the filter elements restores pressure drop loss which occurs as solids
37
-------
co
oo
V
Wc: 12. AMERICAN LAUNDRY mCHIHERY IND3UTRIES WASTE WATER TRfiATMEST SYSTEM
-------
co
10
TO CHLORI NATION,
AND DISCHARGE
TRANSFER
PUMP
•*»-
rCHEMICALS
f
CHEMICAL
TANK
FILTER
PUMP
FLOAT
CONTROL
r
1
HOLDING TANK
No. I
FILTER
I-H-
SLUD
RAW WATER
"FROM WASHER
-«-•
N..2
FILTER
TO SLUDGE
HOLDING TANK
VALVE SETTINGS
PRECOAT ON STREAM DESLUDGE
OPEN 1,2,3,6,7,8 1,2,3,6,7 4,5,6,7
CLOSED 4,5 4,5,8 1,2,3,8
FIGURE 13
SCHEMATIC FLOW DIAGRAM-AMERICAN LAUNDRY
MACHINERY INDUSTRY-DIATOMITE FILTRATION SYSTEM
-------
TABLE 8
AMERICAN LAUNDRY MACHINERY INDUSTRIES
DIATOMACEOUS EARTH FILTRATION SYSTEM
Overall Size
Base
Height
No. Filter Elements
Size
Mesh
Filter Element Area
Total
5'-3" X 5'-5"
7'-2"
90
25.5" long X 1" dia.
60
0.564 ft2/element
50.76 ft2
Normal Flow
In
Out
Flow Loading
Diatomite Charge
Normal Total Daily Flow
Chemical Feed Solution Rate
25-26 gpm
14-15 gpm
0.5 gpm/ft filter area
45 pounds (0.89 Ib./ft )
6300-8500 gals.
60-70 ml./min.
-------
accumulate on the filter elements. Figure 14 illustrates the rate of
pressure drop increase (and flow decrease) as a function of number of
filtration cycles /2) Usually, it is possible to achieve 10-15 filtra-
tion cycles with one DE charge, which allows processing of 4000-6000
gals, of wastewater.
The recommended chemical operation of the ALMI system consists of the
addition of CaCl2 and Roccal (commercial name for a quaternary ammonium
compound which is in effect both a cationic detergent to remove residual
anionic detergents and a germicide to kill bacteria) to the raw waste
in the mixing tank. In addition, NaOH, alum and ferric chloride were
added in tests to study the removal of phosphates. Finally, sodium
hypochlorite (Clorox) was added to the effluent to reduce bacteria.
The entire chemical reactions of the ALMI Wastewater Treatment System
take place in the mixing tank. They are designed to neutralize and/or
precipitate phosphates, spent detergents, nitrates, organic matter and
suspended particulates in the wastes. To the degree that the the chem-
ical process is effective, these substances are then trapped upon the
filter medium, theoretically leaving a clear, odorless and non-pathogenic
effluent low in organic matter.
This entire phase of this study was conducted under less than ideal con-
ditions. Just prior to commencing Part II of this project, an injunc-
tion was obtained against the laundromat operator, forcing him to shut
down his operation. This was due to an overflow of wastes from the
holding tank at the treatment plant. The system was designed so that
when the holding tank was full, the waste would spill over into a septic
tank and leaching system. However, delivery trucks had crushed the pipes
leading to the septic tanks and tile fields, so that the waste overflowed
at the holding tank. Fortunately, the injunction which closed the laun-
dromat said nothing about the treatment plant, so arrangements were made
with the operator of a laundromat about 3 miles away to truck 2,000 gal.
per day from his septic tank to our holding tank. This waste was septic
and not fresh as the local waste was. This probably made the waste more
difficult to treat. It was assumed that if this system could treat this
septic waste satisfactorily, it could do an even better job of normal
fresh laundromat wastes.
-------
o> 3
ul
I 2
u_
25 ._
(0
o.
20
a:
a.
o;
UJ
60
iu 50
o
40
0)
30
g 20
10
I
I
I l
I
0 2 4 6 8 10 12 14 ,16
CYCLES
FIGURE 14-ALMI SYSTEM PRESSURE DROP-
FLOW CHANGES
-------
SECTION X
LABORATORY ANALYSIS
Discussion of the information available from the data is expanded for
each of the parameters measured, and then the most nearly optimum oper-
ating conditions are evaluated.
ABS Removal
With one exception, 97% or better ABS removal was achieved with Roccal
dosages of 26 mg/1 and greater as summarized in Table 9. With one ex-
ception, the ratio of CaCl2 to Roccal ranged between 4.78 5.1 on these
occasions. Poorer ABS removals occurred when the Roccal addition dropped
below 26 mg/1 and the CaC^: Roccal ratio was greater than 10. The sum-
mary of the removal of ABS is shown in Table 10. The concentration of
ABS in the raw waste was fairly constant with a variation only from 16
to 26 mg/1 and an avg. of 20 mg/1. The highest value in the effluent was
5.2 mg/1 and on numerous occasions the ABS was removed completely. The
avg. ABS in the effluent was 2.5 mg/1, representing an avg. reduction of"
87%.
BOD Reduction
The values of the BOD reduction are summarized in Table 11. The highest
BOD recorded in the influent was 371 mg/1, but the next highest value
was 168 mg/1. The avg. BOD of the waste was 126 mg/1. The avg. BOD of
the effluent was 47 mg/1. The avg. reduction was 63%; the max. was 82%
and the minimum 7%. The 82% reduction was achieved using a 4-6 Ib. charge
of Pitcher Celatom and resulted in an actual reduction of BOD from 109
mg/1 to 20 mg/1.
COD Reduction
Table 12 shows the summary of the COD reduction. The COD of the influent
ranged from 200 to 455 mg/1 with an avg. value of 340 mg/1. The values
in the effluent ranged from 42 to 196 mg/1 with an avg. of 104 mg/1. The
greatest reduction of 84% occurred on two occasions and the poorest re-
duction was 31%. The avg. reduction in .COD was 69%. The best COD reduc-
tion was achieved using Diatomite in a 44 Ib. charge resulting in actual
reductions of 258 6 285 mg/1 to 42 g 45 mg/1, respectively.
Turbidity Reduction^
The turbidity of the effluent varied appreciably with the pH as shown in
Fig. 15. (Percent transmittance is plotted instead of actual turbidity;
a high transmittance indicates a low turbidity.) It may be seen that
the best turbidity removal occurs when the pH is adjusted to values
greater than 8. Table 13 shows the variation of the effluent turbidity
with various dosages of each of the diatomaceous earths used. The best
43
-------
TABLE 9
SUMMARY OF ABS REDUCTION WITH VARIOUS
CaCl2 AND ROCCAL ADDITIONS
Date
8/27/69
8/6/69
8/27/69
8/7,8,11/69
9/17/69
8/21/69
8/19/69
8/12/69
8/26/69
8/26/69
9/17/69
8/19,21/69
8/13/69
9/20/69
9/22/69
8/29/69
9/20/69
11/18/69
8/28/69
8/29/69
9/3/69
9/11/69
8/14,15/69
9/3,4/69
Ratio CaCl2
Roccal Dosage (mg/l) To Roccal
110.0
105.0
88.5
84.0
64.0
63.2
63.0
56.0
55.6
48.5
45.0
32.0
29.2
26.2
24.0
23.8 (NaOH Added)
20.2
20.0 (Alum + FeCla Added)
19.8 (NaOH Added)
18.3 (NaOH Added)
15.4 (NaOH Added)
15.2
12.0
9.2 (NaOH Added on 9/3
4.8
4.8
4.6
4.8
4.9
11.5
4.8
4.8
4.8
5.1
4.9
4.8
4.8
9.9
6.75
24.0
9.7
No Data
23.8
23.8
22.7
10.1
4.7
23.7
Average
Reduction %
100
No Data
97.77
100
97.76
99.04
91.59
100.00
99.31
98.10
97.78
98.25
99.37
97.93
38.33*
97.96
88.45 .
No Data,
81.02
80.48
72.43
75.98
77.58
46.34
Only - Results Not
Typical)
1500 mg/l Alum Added, Settled in WWRS Before ALMI Treatment
.44
-------
TABLE 10
SUMMARY OF REMOVAL OF ALKYL BENZENE
; SULFONATE IN THE A.L.M.I. SYSTEM
INFLUENT
High
Low
AVE
Date - mg/1 Date mg/1 mg/1
8/26 25.7 8/8 15.7 20
EFFLUENT
High
Low
Av«
9/3 15.3 8/2,7,8,
11,27
REDUCTION
High
Low
Date mg/1 Date mg/1 mg/1 Date
2.5 8/2,7, 100
8,11,27
Date
9/3
18
87
TABLE 11
SUMMARY OF REDUCTION OF BIOCHEMICAL
OXYGEN DEMAND IN THE A.L.M.I. SYSTEM
INFLUENT
EFFLUENT
High
Low
High
Low
„ _____ - Avg.-
Date mg/1 Date mg/1 mg/1 Date mg/1 Date mg/1 mg/1
8/14 371 8/21 80 126 8/16 102 9/4 15 47
REDUCTION
High
Low
Date
8/21
82
Date
8/16
7.3
AVE
63
-------
TABLE 12
SUMMARY OF REDUCTION OF CHEMICAL OXYGEN
DEMAND IN THE A.L.M.I. SYSTEM
INFLUENT EFFLUENT REDUCTION
High Low Avg. High Low Avg. ' Higfr^^ Low ~~~~ AT
Date mg/1 Date mg/1 mg/1 Date mg/1 Date mg/1 mg/1 Date % Date %
8/19 455 8/8 200 340 8/6,19 196 8/26 42 104 8/26,29 84 8/19 31 69
•F
O>
-------
FIGURE 15- EFFLUENT TURBIDITY VS pH IN THE
A.L.M.I. SYSTEM
too
90
80
o
z
-------
TABLE 13
EFFLUENT TURBIDITY VS. FILTER AID
Filter Aid
Diatomite
Diatomite
Diatomite
Pitcher Celatom
Pitcher Celatom
Pitcher Celatom
Dosage
Lbs.
24
42
44
46
43
50
Average
pH
7.1
7.4
7.4
N.D.
N.D.
9.1
Avg. % Transmittance
87
85
81
61
No Data
96
(NaOH Added)
Diatomite
(NaOH Added)
Diatomite
(NaOH Added)
Diatomite
(NaOH Added)
Diatomite
(NaOH Added)
43
37
43
43
N.D.
N.D.
N.D.
N.D.
91
No Data
No Data*
59.5
Johns-Manvilie
Hyflo-Supereel
Celite 545
44
44.5
N.D. No Quantitative Data (Poor)
7.6
79.5
* Six (6) Minute Precoat Hereafter
48
-------
reduction of turbidity was achieved using Pitcher Celatom at a 50 Ib.
charge resulting in an effluent which manifested 96% transmittance.
Organic Nitrogen
The small number of results for Kjeldahl nitrogen available are summar-
ized in Table 14. Although the data are not statistically significant,
on one occasion there was an increase in the organic nitrogen of 146%
from the influent to the effluent; on the other two occasions there was
a reduction.
Total Dissolved Solids Increase
In all cases, due to the chemicals added for the treatment, there was an
increase in the total dissolved solids as shown in Table 15. The aver-
age increase was 61%. The greatest increase was 144% from 450 mg/1 to
1,100 mg/1. The least increase, 3%, from 390 and 400 mg/1 to 400 and
410 mg/1, respectively, occurred using Diatomite in a 44 Ib. charge com-
bined with 56 mg/1 of CaCl2 and 12 mg/1 of active Roccal. That the
increase in total dissolved solids is directly related to the CaCl2
added is shown visually in Fig. 16.
Hardness
The scant hardness data do not lend themselves to statistical evaluation.
It would be useful to correlate hardness in the effluent with CaCl2 dos-
age, but this is not possible. A summary of the existing data is shown
in Table 16. The hardness in the influent varied only between 172 and
248 with an average of 209 mg/1. On two occasions on the same day there
was an extreme increase in hardness in the effluent to 620 and 668 mg/1.
Including these two values the average hardness in the effluent was 284
mg/1 showing an average increase of 36%. Excluding these two abnormal
values there was an average reduction of 20% to 166 mg/1.
Phosphate Removal
It is well known that phosphate removal is directly related to the pH of
the solution. This is shown clearly in Fig. 17. Below pH 7.5 the phos-
phate removal was in the order of 25%, whereas above pH 8.5 it was above
90%. To show any effect of CaC^ dose on phosphate removal, Fig. 18 was
constructed. It may be seen that increased CaCl2 dosage does result in
a greater removal of phosphate, but this removal approaches only 50%
with CaCl2 dosages up to 700 mg/1. On the other hand, CaCl2 dosages in
the range of 400 to 600 mg/1 removed over 90% of the phosphate when NaOH
was added. When alum was added and the waste settled in the Winfiar sys-
tem prior to treatment in the A.L.M.I, system, an 85% reduction of phos-
phate was achieved using only 150 mg/1 CaCl2- For these reasons, the
summary of the phosphate removal results (Table 17) is divided into sec-
tions showing the removals with CaCl2 alone, with addition of NaOH, and
with alum and settling. The maximum phosphate removal, from 169 mg/1 to
49
-------
TABLE 14
SUMMARY OF CHANGES IN THE ORGANIC
NITROGEN IN THE A.L.M.I. SYSTEM
INFLUENT
High
Low
EFFLUENT
Ave.
High
Low
Date
8/6
mg/1
10.1
Date mg/1 nig/1 Date mg/1
8/7 5.6 7.8 8/7 13.8
Date
8/8
mg/1
7.5
Avg.
mg/1
11.25
CHANGE
High
Low
Date
8/8
-24
Date_
8/7
+146
AVE
01
o
TABLE 15
SUMMARY OF THE INCREASE IN TOTAL DISSOLVED
SOLIDS IN THE A.L.M.I. SYSTEM
INFLUENT
EFFLUENT
High
Low
Avg. High Low Avg.
Date mg/1 Date mg/1^ mg/1 Date mg/jl Date mg/1 mg/1
8/19 690 8/15 390 442 8/21 1,100 8/15 400 713
INCREASE
High
Low
Date
Avg.
Date %
8/21 144 8/15 2.5 61
-------
FIGURE 16- EFFECT OF CaCI2 DOSAGE ON TOTAL DISSOLVED SOLIDS
IN EFFLUENT FROM A.L.M.I. SYSTEM
o
Ul
1201-
co
o
IJ 100
o
CO
o
in
CO
80
60
Ul
CO
<
LU
(T
o
40
20
O
O
O
100 200 300 400 500
Ca CI2 DOSAGE , mg/l
600
700
800
-------
TABLE 16
SUMMARY OF THE CHANGES IN
HARDNESS IN THE A.L.M.I. SYSTEM
01
ro
INFLUENT
High
Date
8/19
mg/1
248
Low
Date
9/3
mg/1
172
Avg.
mg/1
209
EFFLUENT
Low
High Low Avg.
Date mg/1 Date mg/1 mg/1
8/21 668 8/19 96 284
8/19* 218* 166*
CHANGE
High
Low
Date %
8/19 -56
Date_
8/21
+660
Avg.
+ 36
-20*
* Excluding two (2) extremely high values on 8/21
-------
lOOr-
90k
80
70
60
< 50
o
2 40
30
FIGURE 17-EFFECT OF pH ON P04 REMOVAL
10
IN THE A.L.M. I. SYSTEM
8
PH
10
53
-------
too
90
FIGURE 18 - EFFECT OF Ca CI2 DOSAGE ON
£ A P04 REMOVAL IN THE A.L.M.I.
SYSTEM
80
70
CaCI2 ONLY
CaCI2 + NaOH
ALUM ADDED, SETTLED IN
WINFAIR SYSTEM, THEN CoClg ADDED
60
5
so
o.
#
40
30
20
10
100 200 300 400 600
CaCI2 DOSAGE, mg/l
BOO
-------
TABLE 17
SUMMARY OF PO^. REMOVAL IN THE A.L.M.I. SYSTEM
INFLUENT
High
Low
Date mg/^ Date mg/1 mg/1
9/11 199 8/12 84 146
EFFLUENT
REDUCTION
High
Low Av(
Date mg/1 Date m_g_/_l_ mg/1
CaCl2 Only 9/11 199 8/21 55 113
High
Low Avg.
Date % Date _% %_
CaCl2 Only 8/21 50 9/11 0 22.6
9/20 0
en
en
CaCl,
NaOH
8/28 28 8/29 3 11.7
CaCl.
NaOH
8/29 98 8/28 86 94
Alum;
Settled In
Winfair;
Then CaCl2
9/22 36 9/22 9 24
Alum;
Settled In
Winfair;
Then CaCl,,
9/22 95 9/22 80 87
-------
3 mg/1, representing a 98% reduction, was obtained using Pitcher Celatom
in a 50 Ib. charge with the addition of NaOH to a pH of 9.55, and 435
mg/1 of CaCl with 18.3 mg/1 of Roccal (23.77 to 1 ratio).
Alkalinity
The results of the alkalinity are summarized in Table 18. The average
alkalinity in the raw waste was 368 mg/1 with a range of 340 to 420 mg/1.
With no addition of NaOH, there was an average slight reduction in alka-
linity to 329 mg/1. With the addition of NaOH, the alkalinity increased
to an average of 475 mg/1.
Acidity
The results of the acidity are summarized in Table 19. The average acid-
ity in the raw waste was 91 with a range of 73 to 124 mg/1. With no NaOH
added, the average acidity showed a slight increase to 112 mg/1 during
treatment. Upon addition of NaOH the acidity was lowered to an average
value of 31 mg/1, with occasional instances of completely removing the
acidity (pH > 8.3).
Optimum Operating Conditions
There was no one set of operating conditions which produced the maximum
reduction of all parameters of pollution. However, the best overall
results, as shown in Table 20, were produced under the following con-
ditions: (1) 50 Ibs. of Pitcher Celatom as filter aid; (2) a three
minute pre-coat time; (3) 567 mg/1 of CaCl2; (H) 23.8 mg/1 of active
Roccal during a 7,530 gallon run; and (5) with the addition of NaOH.
This combination of treatment resulted in: (1) 98% reduction of ABS
from 21.6 mg/1 to .20 mg/1, satisfactory for USPHS Drinking Water Stand-
ards; (2) a 73% reduction of BOD from 133 to 34 mg/1; (3) an 85% reduc-
tion of COD from 285 mg/1 to 45 mg/1; (4) a 94% reduction of POi^ from
169 mg/1 to 6 mg/1; (5) a 97% transmittance for turbidity of the efflu-
ent; (6) no significant change in acidity; (7) raising the pH from an
influent value of 7.2 to 8.5; (8) increasing the total dissolved solids
(TDS) 44% from 488 mg/1 to 715 mg/1; (9) little change in the alkalinity;
(10) an 8% increase in the hardness from 208 mg/1 to 266 mg/1; and (11)
< 10 coliform/100 ml when chlorinating the effluent.
56
-------
TABLE 18
SUMMARY OF THE ALKALINITY IN THE RAW AND TREATED WASTE
INFLUENT EFFLUENT EFFLUENT
NO NaOH ADDED NaOH ADDED
High
Low
AVE
High
Low
Date mg/1 Date mg/1 mg/1 Date mg/1 Date mg/1
9/3 420 8/21 340 368 8/19 350 8/21 288
Avg.
mg/1
329
High
Low
Date
9/3
mg/1
500
Date
9/3
mg/1
452
m.g/1
475
TABLE 19
SUMMARY OF THE ACIDITY IN THE RAW AND TREATED WASTE
INFLUENT EFFLUENT
NO NaOH ADDED
EFFLUENT
NaOH ADDED
High
Low
Avg.
High
Low
Avg.
Date mg/1 Date mg/1 mg/1 Date mg/1 Date
9/3 124 8/19 73 91 8/19 158 8/19
High
Low
Avg.
mg/1 mg/1 Date tng/1 Date mg/1 mg/1
87 112 9/3 68 9/3 0 31
-------
TABLE 20
OPTIMUM COMBINATION OF CHEMICAL AND MECHANICAL FACTORS
IN REMOVAL OF POLLUTANTS AND PATHOGENS FROM LAUNDROMAT
WASTE WATER IN THE A.L.M.I. WASTEWATER TREATMENT SYSTEM,
FILTER AID-PITCHER CELATOM USING A 3 MINUTE PRE-COAT
TIME-RESULTS BASED UPON 7530 GALLONS OF TREATED WASTE.
en
oo
Filter Aid
Dosage
50 Ibs.
COD
Inf. Eff.
mg/1 mg/1
285 45
Acidity
Inf. Eff.
CaCl2
Dosage
567
(mg/1)
Red'n.
85
Red'n.
%
Active Roccal
Dosage 1
23.8
(mg/1)
TDS
Inf. Eff. Incr.
mg/1 mg/1 %
488 715 44
Alkalinity
Inf. Eff. Incr.
/i <-| g.
NaOH
Yes
Inf.
mg/1
21.6
Turb.
% Trans.
Eff.
ABS
Eff. Red'n. Inf.
.20 98 133
P04
Inf. Eff. Red'n.
mg/1 mg/1 %
97 169 6 94
Hardness Coliform/100
Inf. Eff.
mg/1 mg/1
Incr. Inf.
%
BOD
Eff. Red'n.
mg/1 %
34 73
pH
Inf. Eff.
7.2 8.5
ml
Eff.
91
89
368
372
208
266
> 2,000
< 10
-------
SECTION XI
DISCUSSION OF THE ALMI SYSTEM
The first criterion for a satisfactory effluent is that it meet health
department standards. In New York, this demands (1) an effluent which
manifests a coliform count of zero after chlorination based upon a 1 ml
sample and (2) a reduction of 75% in biological oxygen demand. The ALMI
System meets the requirement with respect to the elimination of coliform
organisms and at optimum conditions achieves a 73% reduction of BOD.
The AriS and total solids in the effluent meet the U.S.P.H.S. drinking
water standards.
The second requirement of a wastewater treatment system is the ability
to handle peak loads as well as normal demands. The ALMI System proved
able to treat a maximum of 25-26 gpm and also produce a satisfactory
effluent at a regular flow of 14-15 gpm resulting in a total daily flow
of 6300-8500 gallons per day. At two runs per day this unit can treat
a total of 7530 gallons per day. At a maximum average flow of 587 gpd
per washing machine as shbwn in Fig. 1, the maximum average daily efflu-
ent from 12-13 machines could be treated in these two runs. It required
252 minutes or 4.2 hours to treat the average daily effluent from approx-
imately seven machines. Based upon a 12 hour day, the ALMI system could
treat the average daily flow from approximately 20 machines. The holding
tank of 4000 gallon capacity provided storage during peak flows.
The third requirement is that it requires a minimum of service, opera-
tional and maintenance skills and operator time. After the optimum com-
bination of chemical and mechanical aids was determined, it required
very little time to add the DE charge and refill the chemical solution
reservoirs. However, with two runs a day, the operator would have to
return to add the second DE charge. All the other operations were such
that the system could be activated automatically by a float valve in
the holding tank. It would be possible to install an automatic DE
charging setup so that the system could operate unattended during the
weekend which is usually the peak usage period of the laundromat. Also
the sludge holding tank must be pumped out periodically, approximately
on a weekly basis. This is best handled by a conventional septic tank
service. ,
/
The fourth criterion is easily met be the ALMI system which was dis-
mantled and removed to the R.P.I, laboratories with a minimum use of
labor and transport facilities. It should be noted, however, that re-
moval of the 4,000 holding tank, 1,000 gal. clean water tank and 1,000
gal. sludge tank was not included, as these are fairly permanently
installed in the ground.
As for the space requirement, the fifth criterion, the ALMI system, ex-
clusive of holding and storage tanks, required no more than 80 square
feet, including storage of filter aids and chemicals, with a normal
ceiling height.
59
-------
An estimate was made for the cost of operation of the system. This was
broken down as follows:
cost/8,500 gal. day
Chemicals $1.00/1,000 gal. $ 8.50
Electric power 1.5 KW/hr., 9 hr./day @ 3C/KW .50
Labor, maintenance 1 hr./day @ $2.25/hr. 2.25
Sludge scavenging $20/wk. 3.00
Misc. .75
Total
Based upon 30 gallons per wash, there are approximately "-*VA" 280 washes
per day. At $15.00 per day, this results in ^fso" 6*/wasn- This value
is slightly high, and would require the addition of at least 5£ to the
cost of each wash. This value does not include amortization of the cost
of the treatment equipment. This would probably increase the total cost
for treatment to IOC per wash. This is a significant increase in the
cost. Thus, this system does not meet the requirements for an economical
system.
The goal of recycling water for further use should be an ultimate aim of
any waste water treatment system. In terms of reduction of spent deter-
gents, phosphates, coliform organisms, turbidity, organic nitrogen, BOD
and COD, the effluent could be reused for uses other than drinking.
However, the increases in TDS, and pH, while within the upper limits of
U.S.P.H.S. drinking water standards, might not be suitable for certain
agricultural and industrial uses. Furthermore, the increase in alkalinity
and hardness, due to the addition of NaOH, and the high ratio of CaCl2
to Roccal (22.3:1) in order to increase PO^ removal, render very question-
able the suitability of the effluent for reuse without softening and pH
adjustment.
The American Laundry Machinery Industries Diatomaceous Earth Filtration
System can thus be an effective system for the treatment of laundromat
wastes. Whereas there was no single optimum operating condition under
which all waste parameters were removed to the greatest extent, there can
be reached an optimum chemical addition and operation which will effect-
ively treat the waste and render it safe for certain reuse or discharge
into a receiving water.
60
-------
SECTION XII
ACKNOWLEDGEMENTS
The laboratory studies in this project were supported by the New York
State Department of Health, Division of Laboratories and Research.
The authors would like to thank Mr. James A. Messina for allowing the
use of his laundromat treatment equipment for this project, Mr. Ralph
Carpenter for providing the building to house and the power to operate
the equipment, and Mr. Edwin Lagasse for cooperating in providing the
laundromat waste . Diatomaceous Earth for this study was provided by
the Johns-Manvilie Corp., Celite Division.
The operational studies were supported by a grant from the Federal
Water Pollution Control Administration (now Federal Water Quality
Administration), Department of the Interior. Special thanks is also
extended to Mr. Richard Keppler, Project Officer, for his guidance.
61
-------
SECTION XIII
REFERENCES
1. Black, Hayse H., and Spaulding, Charles H., "Diatomite Water Filtration
Developed for Field Troops," Jour. AWWA 36_, 1208 (Nov. 1944).
2. Eckenfelder, Wesley, Proceedings of 19th Industrial Waste Conference,
Purdue University, (1964) p. 467.
3. Flynn, J.M., "Long Island Ground Water Pollution Study Project,"
Proceedings at 1st Annual Water Quality Research Sumposium, New York
State Department of He lath, Albany, N.Y. (Feb. 1964).
4. Flynn, J.M., and Andres, B., "Launderette Waste Treatment Processes,"
Jour. Water Poll. Control Fed., 35, 783 (1963).
5. Paulson, E.G., "Organics in Water Supply," Water and Sewage Works,
110, 216, (1963).
6. "Removal of Synthetic Detergents from Laundry and Laundromat Wastes,"
Research Report No. 5, New York State Water Pollution Control Board,
Albany (March I960).
7. Robeck, G.G., Bryant, A.R., and Woodward, R.L., "Influence of ABS on
Coliform Movement Through Water-Saturated Sandy Soils," Jour. AWWA
54_, 75 (1962).
8. Rosenthal, B.L., O'Brien, J.E., Joly, G.T., and Cooperman, A., "Treat-
ment of Laundromat Wastes by Coagulation with Alum and Adsorption
Through Activated Carbon," Mass. Dept. of Public Health, Lawrence
Experiment Station, (March 1963).
9. "Standard Methods for the Examination of Water and Wastewater,"
12th ed., A.P.H.A., New York, (1965).
10. Weber, W.J. Jr., and Morris, J.C., "Kinetics of Adsorption on Carbon
from Solution," Jour. San. Eng. Div., A.S.C.E. 89, SA2, 31 (1963).
63
-------
SECTION XIV
GLOSSARY
ABS - Alkyl benzene sulfonate; a constituent of detergents; in this
paper used to connote both the older branched-chain non-biodegradable
forms and the newer LAS.
Anion An electronegative 3on.
Cation - An electropositive ion.
Cerearia - The larval form of a parasitic worm.
Coliforms - A group of bacteria, native to the human intestinal tract,
used as a water pollution index. The concentration of coliform bacteria
is indicative of the extent of fecal contamination to the water.
Cysts - A capsule surrounding a microorganism in its resting state; it
is shed after the organism resumes activity.
Diatomaceous earth - A fine earth derived from the cell walls of diatoms
and used as an absorbent.
LAS - Linear alkyl benzene sulfcnate; now a conrtituent of the new bio-
degradable detergents.
Roccal - The commercial name for a quaternary ammonium compound which
is both a cationic detergent to remove residual anionic detergents and
a germicide to kill bacteria.
Schistosome - A genus of worm, parasitic in the blood of man.
Syndets - Synthetic detergents.
65
4U.S. GOVERNMENT PRINTING OFFICE: 1973 5U-15J/200 1-3
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SELECTED WATER
RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
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Treatment of Laundromat Wastes
Sept. 1971
Donald B. Aulenbach, Patrick C. Town, Martha Chilson
Rensselaer Polytechnic Institute
Troy, New York 12181
12120 DOD
:-?,TT. - -w Environmental Protection Agency
Pc'\o^ uo'-cr-. Final
3/1/64 - 11/30/69
Environmental Protection Agency report
number, EPA-R2-73-108, February 1973.
Laboratory and field studies were conducted to evaluate the laundromat waste treat-
ment capabilities and the effluent recycling possibilities of two systems. The
Winfair Water Reclamation System (WWRS) involves the addition of alum at a pH of 4,
sand filtration, and passage through an ion exchange resin. The American Laundry
Machinery Industries (ALMI) Diatomaceous Earth Filtration System employs chemical
precipitation prior to filtration.
The WWRS resulted in a 61% BOD reduction, 71% COD reduction, 94% ABS reduction,
and a buildup of total solids in the effluent. The system produced an effluent
suitable for discharge into many streams. For effluent recycling, a functioning
demineralizer would be required.
The ALMI System achieved a 70% BOD reduction, 84% COD reduction, 98% ABS reduction,
94% PO^ reduction, and complete coliform removal. The increase in effluent alka-
linity and hardness render very questionable the suitability of effluent reuse
without softening and pH adjustment. The introduction of the system into existent
laundromats would increase the cost of washes by about IOC.
Ids x'
JO.
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