-------
TABLE 5-24. TOXIC POLLUTANT CONCENTRATIONS AND LOADINGS IN TUNNEL
TYPE CAR WASH RAW WASTEWATERS
Pol lutant
Antimony
Arsenic
Beryl 1 f urn
Cadmium
Ch rom 1 urn
Copper
Lead
Mercury
Nickel
Seleni urn
Silver
Thai 1 i urn
Zinc
Number3
1/1
4/17
0/17
17/17
17/17
8/8
17/17
6/17
17/17
0/1
0/1
0/1
17/17
Maximum
Cone b
0.0045
0.016
__
0.066
1.7
0.3
2.2
0.0005
0.69
--
__
1.5
mg/1
Median,
Cone b
__
<0.01
--
0.014
0.026
0.10
0.55
<0.0001
0.13
—
—
__
0.55
Mean,
Cone
=_
0.0018
- =
0.022
0.14
0.15
0.78
0.00011
0.19
--
—
_.
0.70
kg/day
Avg/
Facility
=_
0.00014
--
0.0017
0.011
0.011
0.059
0.0000083
0.014
•
__
-.
0.053
Bis(2»ethylhexyl)
phthalate 1/1
Methylene
chloride
4-ni trophenol
1/1
1/1
0.027
0.011
0.011
a Ratio indicates the number of samples in which the specific pollutant was
found as compared to the total number of samples analyzed.
b Blanks indicate values below analytical detection limits. Appendix A
representative detection limits for each organic toxic pollutant.
75
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TABLE 5-25 NUMBER OF DIRECT DISCHARGERS IN THE LAUNDRY INDUSTRY
Subcategory
Industrial
Laundries
Linen supply
Power laundries
Diaper services
Total
Number
1,000
1,300
3,100
300
Direct
Number
0
1
16
0
Dischargers
Percent
0
0.1
0.5
0
Carpet and upholstery
cleaners 2,700
Coin-operated
laundries
Dry cleaning
plants
Car washes
32,000
28,400
22,000
140
6
100
0.1
0.4
0.1
0.5
76
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SECTION 6
SELECTION OF SUBCATEGORIES AND POLLUTANTS FOR REGULATION
This section identifies those subcategories and pollutants to be regulated and
those to be excluded from regulation in the Auto and Other Laundries point source
category. The reasons for exclusion or regulation are presented for each
subcategory and are based on wastewater volumes and characteristics presented in
Section 5.
6.1 SELECTED SUBCATEGORIES AND POLLUTANTS
Based on analytical data presented in Section 5 and on information from
industry contacts, both industrial laundries and linen supply laundries are being
recommended for discharge regulations.
6.1.1 Industrial Laundries
Industrial laundries clean garments and other materials from a variety of
industrial activities. Consequently, toxic pollutant loads generated in this
subcategory are the highest in the industry. The concentrations of toxic metals in
the raw waste at industrial laundries range from <0«00026 mg/1 for beryllium to 4.5
mg/1 for lead. Those in the highest concentrations are lead, zinc, copper, and
chromium whose average concentrations are 4.5 mg/1, 3.0 mg/1, 1.7 mg/1, 0.88 mg/1,
respectively. When toxic organics are found, they are generally present only in
minor concentrations. However, tetrachloroethyiene and toluene have been found at
certain locations in very high concentrations (maximum tetrachloroethyiene
concentration found was 93»2 mg/i while that for toluene was 50.9 mg/1). These high
values have tended to skew the average concentration of these toxic organics to the
high side. The average concentrations of tetrachloroethyiene and toluene are 9.1
and 5.2 mg/1, respectively.
Copper, chromium, lead, and zinc were selected for regulation in this
subcategory. As stated above, these toxic metals were found in the highest
concentrations, and are the primary contributors to the total toxic metal loadings
from industrial laundries (average 2.65 kg/day per facility for the combination of
the four metals versus an average 0.31 kg/day per facility for all other toxic metals
combined).
77
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6.1.2 Linen Supply
Total toxic metals in the raw waste at linen suppiy laundries average 0.85
kg/day per facility. This load is significantly below that generated at industrial
laundry sites and is nearer that generated at diaper service facilities. However, as
discussed in Section 3.1.2, many linen supply laundries are expanding their services
to include work traditionally done by industrial laundries. As this occurs, the degree
to which industrial laundering is conducted at a linen supply facility will be
reflected in the wastewater generated. Because of this trend, the Agency has
decided to regulate linen supply laundries in addition to industrial laundries.
As in industrial laundries, the same toxic metal pollutants (copper, chromium,
lead, and zinc) are the primary contributors to the average total toxic metal
loading. Toxic metals average 0.85 kg/day per facility with copper, chromium, lead,
and zinc contributing some 0.81 kg/day per facility of the total. For this reason,
these pollutants are recommended for regulation.
6.2 EXCLUDED SUBCATEGOREES AND POLLUTANTS
6.2.1 Excluded Subcategories
6.2.1.1 Power Laundries, Family and Commercial
Summary of Determinations - It has been determined that no further effort
will be given to developing regulations for this subcategory. The bases for this
determination are Paragraph 8(a)(iv) of the Consent Decree, which states "the
amount and toxicity of each pollutant in the discharge does not justify developing
national regulations" and Paragraph 8(b)(ii) which states "the toxicity and the
amount of incompatible pollutants (taken together) introduced by such point sources
into treatment works that are publicly owned is so insignificant as not to justify
developing a pretreatment regulation."
Production Process and Effluents - Power laundries are establishments
primarily engaged in operating mechanical laundries with steam or other power.
The average wastewater discharge for this subcategory is 230 m^/day per facility.
The average total toxic metals is less than 0.23 kg/day per facility, which consists
primarily of zinc, 0.099 kg/day per facility, copper, 0.037 kg/day per facility, and
antimony, 0.037 kg/day per facility. Of the toxic organics, phenol is the major
constituent with the average facility discharging 0.071 kg/day.
Plants - There are some 3,100 power laundry facilities in the country.
Status of Regulations - There are no existing regulations for this subcategory.
6.2.1.2 Diaper Services
Summary of Determinations - It has been determined that no further effort
will be given to developing regulations for this subcategory. The bases for this
determination are Paragraph 8(a)(iv) of the Consent Decree, which states "the
amount and toxicity of each pollutant in the discharge does not justify developing
national regulations" and Paragraph 8(b)(ii) which states "the toxicity and the
amount of incompatible pollutants (taken together) introduced by such point sources
78
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into treatment works that are publicly owned is so insignificant as not to justify
developing a pretreatment regulation."
Production Process and Effluents - Diaper services are establishments
primarily engaged in supplying diapers (including disposables) and other baby linens
to homes. The average wastewater discharge rate for this subcategory is 160
m^/day per facility. The average total toxic metals for this subcategory is 0.95
kg/day per facility, which consists primarily of zinc, 0.91 kg/day per facility. Toxic
organics were found in only very small quantities.
Plants - There are some 300 diaper service establishments in the country.
Status of Regulations - There are no existing regulations for this subcategory.
6,2A3 Coin-operated Laundries and Dry-Cleaning
Summary of Determinations - It has been determined that no further effort
will be given to developing regulations for this subcategory,, The bases for this
determination are Paragraph 8(a)(iv) of the Consent Decree, which states "the
amount and toxicity of each pollutant in the discharge does not justify developing
national regulations" and Paragraph 8(b)(ii) which states "the toxicity and the
amount of incompatible pollutants (taken together) introduced by such point sources
into treatment works that are publicly owned is so insignificant as not to justify
developing a pretreatment regulation."
Production Process and Effluents - The coin-op category is made up of
establishments primarily engaged in providing coin-operated laundry and/or dry-
cleaning equipment on their own premises. Wastewater flows from coin-op
establishments average 14 m^/day. Total average toxic metal discharge is 0.01
kg/day per facility, most of which is zinc, 0.0043 kg/day per facility. Toxic organics
are present only in very small quantities.
Plants - There are approximately 32,000 coin-op facilities in the country.
Status of Regulations - There are no existing regulations for this subcategory.
6.2.1.4 Dry-Cleaning Plants, Except Rug Cleaning
Summary of Determinations - It has been determined that no further effort
will be given to developing regulations for this subcategory. The bases for this
determination are Paragraph 8(a)(iv) of the Consent Decree, which states "the
amount and toxicity of each pollutant in the discharge does not justify developing
national regulations" and Paragraph 8(b)(ii) which states "the toxicity and the
amount of incompatible pollutants (taken together) introduced by such point sources
into treatment works that are publicly owned is so insignificant as not to justify
developing a pretreatment regulation."
Production Process and Effluents - The dry-cleaning subcategory consists of
establishments engaged in dry cleaning or dyeing apparel and household fabrics,
other than rugs, for the general public. Wastewater discharge from the dry-cleaning
industry is very small. Average total toxic metals is less than 0.01 kg/day per
facility and total toxic organics is less than 0.59 kg/day per facility.
79
-------
Plants - There are some 28,400 dry-cleaning plants in the country.
Status oi Regulations - There are no existing regulations for this subcategory.
6.2.1.5 Carpet and Upholstery Cleaning
Summary of Determinations - It has been determined that no further effort
will be given to developing regulations for this subcategory. The bases for this
determination are Paragraph 8(a)(iv) of the Consent Decree, which states "the
amount and toxicity of each pollutant in the discharge does not justify developing
national regulations" and Paragraph 8(b)(ii) which states "the toxicity and the
amount of incompatible pollutants (taken together) introduced by such point sources
into treatment works that are publicly owned is so insignificant as not to justify
developing a pretreatment regulation."
Production Process and Effluents - Carpet and upholstery cleaners are
establishments primarily engaged in cleaning carpets and upholstered furniture at a
plant or on a customer's premises. Wastewater flows from this subcategory are
extremely small. Average total toxic metals is less than 0.073 kg/day per facility,
with the primary constituents being zinc and copper.
Plants - There are some 2,700 carpet cleaning establishments in the country.
Status of Regulations - There are no existing regulations for this subcategory.
6.2.1.6 Laundry and Garment Services, Not Elsewhere Classified
Summary of Determinations - It has been determined that no further effort
will be given to developing regulations for this subcategory. The bases for this
determination are Paragraph 8(a)(iv) of the Consent Decree, which states "the
amount and toxicity of each pollutant in the discharge does not justify developing
national regulations" and Paragraph 8(b)(ii) which states "the toxicity and the
amount of incompatible pollutants (taken together) introduced by such point sources
into treatment works that are publicly owned is so insignificant as not to justify
developing a pretreatment regulation."
Production Process and Effluents - This subcategory consists of those
establishments primarily engaged in furnishing other laundry services, including
repairing, altering, and storing clothing for individuals, and the operation of
Chinese, French, and other hand laundries. Wastewater flows for this subcategory
are small due to the limited amount of laundering done within this subcategory.
Plants - There are some 2,700 establishments included in this subcategory.
Status of Regulations - There are no existing regulations for this subcategory.
6.2.1.7 Car Wash Establishments
Summary of Determinations - It has been determined that no further effort
will be given to developing regulations for this subcategory. The bases for this
determination are Paragraph 8(a)(iv) of the Consent Decree, which states "the
amount and toxicity of each pollutant in the discharge does not justify developing
80
-------
national regulations" and Paragraph 8(b)(ii) which states "the toxicity and the
amount of incompatible pollutants (taken together) introduced by such point sources
into treatment works that are publicly owned is so insignificant as not to justify
developing a pretreatment regulation."
Production Process and Effluents - The car wash subcategory is comprised of
facilities designed for the automatic or self-service washing of vehicles including
cars, vans, and pick-up trucks. There are three types of car washes, tunnel,
rollover, and wand which were described in Section 3.2.5. Average wastewater
flows for tunnels, rollovers, and wands are 75.7, 11.4, and 19.9 m^/day, respectively.
Average toxic metals is less than 0.17 kg/day per facility for tunnels, less than 0.12
kg/day per facility for wands, and less than 0.15 kg/day per facility for rollovers. In
all cases, zinc and lead were the major constituents of the total toxic metals. Toxic
organics were found in very small quantities.
Plants - There are some 22,000 car wash establishments of which an estimated
15,000 are tunnel, 3,500 are wand, and 3,500 are rollover.
Status of Regulations - There are no existing regulations for this subcategory.
6.2.2 Specific Pollutants Excluded from the Industrial Laundry and Linen Supply
Subcategories
6«,2e2=i Toxic Metals
Toxic metals other than those selected for regulation are excluded from
regulation under Paragraph 8(a)(iii) of the Consent Decree because they are present
only in trace amounts (average total toxic metals are 0.31 kg/day per facility for
industrial laundries excluding those being regulated) and are neither causing or are
likely to cause toxic effects or because they are present in amounts too small to be
effectively reduced. Appendix A provides the specific basis for the exclusion of
each of the toxic metal pollutants.
6.2.2.2 Toxic Organics
A variety of toxic organics were observed in raw waste samples from
industrial laundry wastewaters and several organics were observed at significant
concentrations. However, an evaluation of the occurrence, solubility and
treatabiiity of the various toxic organics has revealed the following problems
associated with regulating these pollutants:
o The organics occur erratically from one laundry to another and within
the same laundry (see Appendix C).
o The solubilities of the organics in oil range from slight to infinite.
Therefore, the degree to which oils are removed by DAF treatment will
be reflected in the removal of some but not all organics.
o Sampling data has shown that DAF treatment reduces total toxic
organics by 77 percent (see Section 7).
o The addition of applicable technologies, following DAF, for the specific
81
-------
control of toxic organics not reduced by DAF was found to be either
technically unfeasible because of the characteristics of DAF effluent or
economically prohibitive for this industry.
Based on the,above considerations and under the authority of Paragraph 8 of
the Settlement Agreement,*, the Agency is excluding toxic organics from regulation.
Specifically, Paragraph 8(a)(iii) allows exclusion of toxic pollutants present only in
trace amounts, in amounts too small to be effectively reduced, or "pollutants that
will effectively be controlled by technologies upon which are based other effluent
limitations and guidelines, standards of performance, or pretreatment standards."
Appendix A provides the specific basis for the exclusion of each of the toxic
organic pollutants.
82
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SECTION 7
CONTROL AND TREATMENT TECHNOLOGY
Technology applicable to the control and treatment of laundry wastewaters is
described in this section. Description and evaluation of all technology are based on
treatment system applicability in removing various pollutants prior to discharge to
POTW's or before direct discharge to navigable waterways. Those pollutants found
most consistently and/or at the highest concentration, as presented in Section 5, are
used as a basis for evaluation of current and potentially applicable technology. The
following subjects are discussed in this sections
o Pretreatment technology
o Treatment for direct discharge
o Recycle/reuse technology
o Sludge handling and disposal
Pretreatment of laundry wastewater for discharge to a POTW is classifed into
three types: (1) conventional, in-piant controls, (2) physical-chemical treatment
systems presently applied, and (3) potentially applicable treatment technology.
Conventional controls are designed to remove gross pollutants such as lint and sand
which obstruct piping and sewer drains, disrupting laundry operations and increasing
plant maintenance costs. In addition, heat reclaimers may be used to reduce the
temperature of the effluent through preheating of incoming fresh water. Physical-
chemical treatment systems (PCS's) are designed to meet regulations established for
the control of pollutants which may include oil and grease and heavy metals, and
high pH as defined by sewer ordinances for various municipal districts. Some
physical-chemical systems are designed for the expressed purpose of reclaiming
laundry wastewater for use in the wash process.
Controls required for direct discharge of laundry wastewaters are specified, in
this section, as a combination of physical-chemical treatment and on-site biological
treatment. Further removal of the pollutants mentioned above is required in
addition to reducing levels of BOD and TSS before direct discharge. Assessment of
the capabilities of small-scale biological systems for treatment of laundry
wastewater is based on limited data from coin-operated laundries.
Recycling or reusing laundry wastewater can achieve a reduction in the
volume of effluent per unit mass of laundry washed. In cases where recycle or reuse
is practiced, effluents from various systems treating laundry wastewater are mixed
with incoming fresh water and then recycled through the wash process. An example
of one reuse practice is utilization of untreated rinse water from one washload as
initial washwater for a second washload. The technical feasibility of recycling
laundry wastewater is discussed in Section 7.3.
83
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Sludges resulting from the treatment of laundry wastewater must be handled
and disposed of. Dewatering equipment, for the purpose of reducing sludge volume,
is described in Section 7.4. Ultimate disposal of laundry sludge is accomplished by
landfilling or incineration.
7.1 PRETREATMENT TECHNOLOGY
Since greater than 99% of all laundries discharge to POTW's removal of
incompatible pollutants is of major concern when describing wastewater controls for
the laundry industry. The extent and type of control practiced by individual
laundries has been dependent on local sewer ordinances, geographic location, POTW
limitations, and economic considerations. In Table 7-1, the number of plants in each
laundry subcategory having various control technologies is estimated from the
technical survey.
7.1.1 Conventional Technology
Generally, conventional technology is designed to remove gross pollutants such
as lint, sand, grit, and free oil. Heat reclaimers are used to recover heat from the
wastewater prior to discharge in order to preheat incoming fresh water.
Conventional equipment for the control of solids, free oil, and temperature is
described in the following subsections.
7.1.1.1 Solids Removal
Bar screens, lint screens, and catch basins (settling pits) are devices used to
remove sand, grit, lint, and other noncolloidal solids from laundry wastewater.
Solids removal is typically accomplished in many laundries .to prevent the
obstruction of piping and drains, thus ensuring constant hydraulic capacity.
Bar screens are constructed of flat steel bars welded together in a grid
pattern. Rectangular spaces formed by the steel grid are 6.3 mm (0.25 in.) by 19
mm (0.75 in.) in area and are designed to allow the free flow of effluent while
removing large objects composed of paper, wood, etc., from the wastewater stream.
In the laundry industry, bar screens are usually cleaned by hand.
Lint screens are usually installed after bar screens and will remove lint and
other particles such as sand and grit. Lint screens at laundries are generally of
cylindrical or rectangular design, are constructed of wire mesh or perforated metal
plate, and have openings 9.5 mm (0.37 in.) to 3.2 mm (0.12 in.) in width. They are
manually or mechanically cleaned. Hand cleaning of a lint screen is accomplished
by directing a stream of water from a hose against the screen in a direction opposite
to the wastewater flow. Mechanical removal of accumulated debris is mainly
accomplished by rotating or vibrating the lint screen to allow the trapped lint to fall
off and be collected. Automatic water jets may also be used to aid in the removal
of trapped lint from screens. •
Catch basins are also used in combination with lint screens to remove sand and
grit from laundry wastewater. Catch basins are typically built below ground and
have a hydraulic detention time of between 15 min and 40 min. Basins rely on the
84
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TABLE 7-1. ESTIMATED PERCENT OF LAUNDRIES (BASED ON
TECHNICAL SURVEY DATA) HAVING CONTROL
TECHNOLOGY
Control technology
Industrial
laundries
Linen supply
laundries
Pretreatment technology
(Number of responses)
Bar screens
Lint screens
Catch basins
Heat reclaimers
Oil skimmers
Equalization tanks
pH adjustment
Physical-chemical systemsc
Otherd
2.7
70
72
70
15
1.2*
8.1
(59)
5.1
81
78
81
0
2elb
5.1
0.3b
3.4
Estimate based on 13 physical-chemical systems operating at the 1,013 industrial
laundry indirect discharges. Also, 12 of these systems have equalization tanks.
Estimate based on 5 physical-chemical systems with equalization operating at
the 1,308 linen supply indirect discharges, plus the 1.796 of linen supplies that
have equalization tanks based on survey responses.
Major unit operations consist of chemical addition and floe removal by dissolved
air flotation.
Other includes filtration, separators, oil hold back devices, and miscellaneous
operations.
85
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difference in the specific gravities of soiids versus water to achieve particle
settling. The effectiveness of solids settling will depend upon the characteristics of
the particular laundry wastewater and the hydraulic detention time of the catch
basin. The percent of total solids removed will generally increase, to a maximum,
with increasing detention time.
Holding tanks with detention times of 2 to 4 hours are considered adequate for
providing flow equalization of laundry effluent. Detention times of this magnitude
will usually provide the maximum removal of suspended solids achievable without
resorting to additional technology such as physical-chemical treatment. Physical,
chemical, and biological reactions can also occur in an equalization tank, which may
cause reductions in pollutant concentrations (46). Details on the functions of flow
equalization are given as part of the general description of dissolved air flotation
treatment.
7.1.1.2 Free Oil Removal
Oils and greases in laundry wastewater are compounds that can be separated
from water by freon, hexane, and/or ether extraction. Non-emulsified or free oil
may comprise a portion of the total oil and grease in a particular laundry
wastewater. Data collected from industrial laundries indicate that 5% to 10% of
the total oil and grease loading may be free oil.
Free oil removal technology relies on differences in specific gravities of oils
and grease versus water (24). Treatment techniques involve retention of the oily
water in a holding tank allowing gravity separation of the oily material from water
to occur. The floating oils are then skimmed from the water surface.
7.1.1.3 Temperature Control
Heat reclaimers are used in the laundry industry to preheat incoming fresh
water prior to its use in the wash process. Preheating is accomplished with
reclaimers by noncontact heat transfer from laundry wastewater. As a result,
laundry effluent temperatures are reduced from 60%C-70%C (140%F-160%F) to
27%C-38%C (80%F-100%F). Preheating of washwater with heat reclaimers reduces
the amount of fuel needed to heat fresh water.
7.1.1.4 Capabilities of Conventional Technology
Data are provided in Table 7-2 for control equipment presently in place at
three laundries. The system, consisting of bar screen, lint screen, catch basin and
heat reclaimer, was selected as typical because it is in place at 70 percent or more
of industrial and linen supply laundries as presented in Table 7-1 survey data.
The data in Table 7-2 indicate that the effectiveness of conventional
treatment in removing pollutants, is variable and the results are basically
inconclusive. Median removal rates ranged from zero to 32 percent for conventional
and toxic pollutants. For the purpose of evaluating other treatment technologies,
conventional treatment is assumed to be in place providing for the removal of gross
pollutants only.
86
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7.1.2 Incompatible Pollutant Removal — Presently Applied Technology
Laundries operating under regulations that limit the discharge of incompatible
pollutants are currently using dissolved air flotation systems (DAFS) for wastewater
treatment. This system is described in the following section.
7.1.2.1 General Treatment Strategy
DAF treatment of laundry wastewater is comprised of the following unit
operations: flow equalization, chemical addition, floe removal, and sludge disposal.
Figure 7-1 is a block diagram for laundry wastewater pretreatment using DAF
technology. Conventional controls, such as lint screens and catch basins are
considered to be already installed in laundries and will not be discussed further.
Equalization tanks were briefly described under conventional equipment, however
their use in the laundry industry has been mainly restricted to providing constant
flow to DAF systems.
Flow Equalization - Equalized flow is defined as the constant flow of laundry
wastewater through the treatment system. Flow is constant if it is maintained at
approximately the same level during the entire period of operation of the DAF
system. For laundries this period of time is usually 8 to 10 hours. A secondary
objective of equalization is to dampen the mass flow variation of wastewater
contaminants by blending (25). Reductions in the variation of flow and pollutant
concentrations will minimize the required capabilities of a particular treatment
system. Because laundry wastewater flows and pollutant concentrations can vary by
orders of magnitude during a day's operation, flow equalization prior to DAF
treatment is a recommended technique.
Equalization tanks currently in use at laundries are of steel or concrete
construction and are built above or below ground. Hydraulic detention time for
laundry wastewater equalization is usually 2 to 4- hours, dependent on washroom
operation, building space limitations, and design criteria of the DAF system.
Equalization tanks at laundries require cleaning on a regular basis to remove settled
solids and grease deposits. The approximate areas required for equalization tanks
are given in Table 7-3 for 2-hr and 4-hr detention times of various wastewater
flowrates.
Chemical Addition - Pollutants, such as oil and heavy metals in laundry
wastewater, are usually in the form of colloidal suspensions which cannot be
effectively treated solely by physical techniques. Chemical addition is thus used to
aggregate the colloidal material into particles that can be physically removed by
flotation, sedimentation, or filtration.
Emulsified oil and grease is aggregated by chemical addition through the
processes of coagulation and/or acidification in conjunction with flocculation
mechanisms. Coagulation involves the use of chemical additives that destabilize the
colloidal material either by reducing the electrostatic repulsive forces between
colloids or by forming positively charged hydrous oxides which are absorbed on the
surface of the colloid (24, 27). Other pollutants such as lead, copper, and zinc,
which exist as colloids in laundry wastewater are also destabilized by coagulation.
Acidification of oil and grease colloids is accomplished by lowering the pH to a point
where the emulsion is "broken", thus allowing dispersed oil droplets to aggregate
88
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S
89 •
-------
TABLE 7-3 AREA REQUIREMENTS FOR LAUNDRY
WASTEWATER EQUALIZATION .
Selected
flowrate,
m3/day
(gal/day)
570
(150,000)
380
(100,000)
280
(75,000)
190
•(50,000)
38
(10,000)
19
(5,000)
Tank
capacity,
m3
(gal)
Tank
area,k
m3
Cft2)
*a x»
detention time '
• Two-hour
210
(56,000)
130
(35,500)
110
(28,000)
71
(18,700)
15
(4,000) •
8
(2,000)
100
(1,100)
63
(680)
50
(530)
33
(360)
7
(75)
4
(40)
Tank
capacity,
m3
(sal)
detention
Tank
area,t>
m-5
Cft2)
timea'c
Four-hour
360 170
(94,000) (1,800)
240
(62,500)
180
(47,000)
120
(31,000)
23
(6,000)
11
(3,000)
110
(1,200)
•84
(900)
56
(600)
11
(115)
6
(60)
a In determining required tank capacity an additional hour detention time
was factored into the calculation. Variations in wastewater flow over a
normal day's operation are assumed to be minimal for this example;
therefore, tank sizes shown should be considered the minimum required
for laundry wastewater flow equalization.
Tank area has been determined assuming a tank water level of 7 ft.
c Based on 10-hour day.
90
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(24). Coagulation and acidification may both be used in a DAF system to treat
iaundry wastewater.
Flocculation - Floccuiation is defined as partide transport and contact
occuring as a result of colloidal destabilization (coagulation). Particle transport
occurs due to thermal motion, bulk fluid motion (accomplished by mechanical
stirring), and differential settling (26). In all cases floes properly formed from
interparticle contact are then capable of being removed by physical means.
Destabilization of colloidal suspensions in laundry wastewater is accomplished
by adding coagulant chemicals at prescribed rates to the raw wastewater. Coagu-
lants currently in use at laundries are listed below:
Aluminum sulfuate (Alum, Al2 (50^)3)
Calcium chloride (CaCl2)
Ferric sulf ate ^62(50^)3)
Ferrous sulf ate (Fe(SO^))
Cationic polyelectrolytes
Floe particles that form as a result of chemical coagulation contain the
colloidal material intended for removal. Since proper floe formation is dependent
on various particle transport mechanisms (flocculation), the physical design of
chemical addition equipment must provide adequate time and mixing for
interparticle contacts during coagulation.
Design parameters considered important in achieving proper particle contact
include hydraulic detention time in the mix tank and the physical methods used for
mixing. Generally, the required detention time for flocculation is inversely
proportional to solids concentration (26). Baffles are generally used in mix tanks to
provide adequate particle contact through mixing. Additional mixing is also
provided through turbulence that occurs during stream pressurization due to
pumping and air injection. The main purpose of stream pressurization is for floe
removal by dissolved air flotation. This operation is discussed in the following
section.
Dissolved Air Flotation - In the pretreatment of laundry effluents, floe is
brought to the surface of a thickener unit by means of dissolved air flotation (DAF).
DAF is accomplished by pressurizing all or part of the effluent stream with air at 40
psig to 80 psig. Since the pressure exerted on the wastewater is greater than
atmospheric, the saturation point of air in water is raised, allowing excess air to
become dissolved. After the additional air is dissolved in the wastewater, the
pressure is reduced back to atmospheric, forcing dissolved air out of solution in the
form of minute bubbles throughout the entire volume of the liquid (23). These
bubbles become attached to floe particles causing them to rise to the surface of a
flotation tank (thickener), where the floe solids can be skimmed off by rotating
troughs or moving blades.
The principal components of a DAF unit are a pressurizing pump, retention
tank, pressure-reducing valve, air injector, and a flotation tank. For laundry
wastewater, two modes of pressurization are currently in use: full flow
pressurization (FFP) and recycle pressurization (RP). In FFP the entire effluent
stream is pressurized. In RP a stream of treated water is drawn from the flotation
91
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tank, ranging in volume from 50% to 120% of the effluent stream; this recycle
stream is pressurized and mixed with the effluent as it enters the flotation tank.
Factors that affect the design of a DAF unit include feed solids concentration,
hydraulic loading rate, and particle rise velocity (28). Ainsolids ratios are
frequently used to determine the design criteria for DAF systems. This ratio is
defined as the weight of compressed air utilized during pressurization compared to
the weight of solids entering the flotation tank (23). Typical airtsolids ratios for
DAF units are in the range of 0.005 to 0.1 (23, 27). Higher air:solids ratios can
cause floe shearing due to increased turbulence, resulting in an overall loss of
system efficiency.
The operating variables, air:solids ratio, hydraulic loading rate, and solids
loading rate have a direct effect on the performance of a DAF unit. For effective
treatment it will usually be necessary to conduct tests at the particular laundry
before installation of a full-scale DAF unit since large variations exist in
contaminant loadings and hydraulic loadings between laundries.
Pretreatment technology using DAF is being practiced at a number of
industrial and linen supply laundries. The results of sampling of wastewaters at 14
of these operational systems are presented in Appendix C. Table 7-4 summarizes
the removal efficiencies of selected industrial laundry DAF systems in terms of
percent removal and treated effluent quality for conventional and toxic pollutants.
The data in Table 7-4 indicate that DAF treatment is effective in reducing
toxic metals. Average lead and zinc removals were greater than 90 percent.
Copper removal averaged 75 percent and chromium removal averaged greater than
57 percent. Detracting from the efficiency of the DAF system, however, are the
variations that exist between different plants and among the various pollutants. For
example, chromium removal ranged from 41.8 percent at Plant D to 99.7 percent at
Plant L, and the concentration of chromium at the same plants was 0.57 mg/1 and
0.005 mg/1, respectively. This variability in the effectiveness of the same
treatment technology is believed to be the result of varying system parameters such
as air flow, chemical addition, and raw waste characteristics.
The data also shows that the DAF system is effective in removing toxic
organic pollutants from laundry wastewater. The removal of total toxic organics
was significant with an average removal of 77 percent and a range of 53.9 percent
to 92.7 percent. Although DAF systems are not designed to remove organics, the
removal of oil and grease accomplishes an incidental removal of toxic organics
soluble in the oil. Quantifying effluent quality in terms of toxic organics is
difficult, however, because of the variations in specific organics found from plant to
plant, the range of solubilities of those organics, and the variations in oil and grease
removal that can occur with the DAF system.
7.1.3 Incompatible Pollutant Removal - Potentially Applicable Technology
Technologies not used on a commercial scale but applicable to laundry
wastewater treatment include gravity settling, multimedia filtration, ultrafiltration,
diatom aceous earth filtration, and electrocoagulation. These technologies include
processes which may replace certain unit operations (such as gravity settling
92
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replacing DAF) or which may replace the entire physical-chemical process (such as
ultrafiltration replacing a DAF system).
7.1.3.1 Gravity Settling
Gravity settling or sedimentation may also be used to remove floe particles
from the laundry wastewater. After chemical addition, wastewater flows into a
tank (clarifier) having sufficient detention time to allow floe particles to settle.
Moving scrapers located at the bottom of the tank collect the settled floe and
discharge it to a sludge collection tank.
At present, pretreatment of laundry wastewater incorporates DAF rather than
gravity settling for floe removal. A system utilizing sedimentation is currently
treating the effluent from one institutional laundry (with a workload comparable to
that of a power laundry) for direct discharge. It is difficult to compare the
effectiveness of these two techniques, since available data involving laundry
applications are limited. DAF units generally operate at surface loading rates four
to eight times higher than gravity settlers. That is, the detention time required and
thus the capacity or volume of the DAF unit would be significantly less than a
gravity settler. Since laundries often have little space for treatment equipment, a
PCS with DAF is normally chosen due to the significant difference in required tank
volumes.
7.1.3.2 Filtration
Further removal of floe from laundry wastewater may be accomplished by
multimedia filtration. In general, those systems whose main purpose is to recyle
part of the laundry effluent utilize filtration, while systems discharging all treated
effluent to a POTW do not incorporate filtration. Variability in final effluent
quality due to floe carryover or very fine floe particles may be reduced by the use
of a multimedia filter.
Filters are sealed cylindrical tanks containing layers of filter media of
different specific gravities and particle sizes. Media are arranged so that the
heaviest material of the finest grade rests at the bottom of the tank. Wastewater is
pumped under pressure through the top of the filter, coming in contact first with a
coarse medium of low specific gravity. As water flows through the filter it
encounters media of increasingly finer grades and greater densities. Total head loss
across the filter increases as particles become trapped in the media. When head loss
raches a predetermined level, the influent flow is shut off and the filter is
backwashed with air and water in the direction opposite to influent flow (27).
As previously cited, however, a certain amount of variability in the efficiency
of a DAF system exists, and increases in effluent oil and grease will readily clog or
block a filter. For this reason, filtration following DAF is not considered feasible
for general application in this industry.
7.1.3.3 Ultrafiltration
Ultrafiltration is a process in which wastewater is pumped through a
semipermeable polymeric membrane at an operating pressure of 80 psig to 100 psig.
Water and most dissolved materials pass through the membrane, while suspended
94
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solids and other colloidal materials such as emulsified oils are retained and
concentrated. The capacity of a UF membrane to pass water is an important design
criterion. The rate of filtration is termed flux, which is the volume of water
permeated per unit membrane area per unit time, usually expressed as gallons per
square foot.
Bench-scale and pilot scale tests have been performed to determine the
effectiveness of UF in treating laundry wastewaters (14). Results have indicated
that although pollutant removal rates are on the order of 95 percent for metals and
conventional pollutants, clogging and fouling of the membrane reduced membrane
flux to levels too low for industrial application,,
From a technical standpoint UF systems with tubular modules have advantages
over physical-chemical systems utilizing chemical addition and DAF. UF does not
incorporate coagulation; thus it does not require chemical additives. In terms of
space requirements, UF systems would require less space than comparable physical-
chemical systems with DAF. This is due to the number of unit operations involved
in each system; these are chemical addition, DAF, and possible filtration for PCS's,
versus filtration for UF systems.
When considering the cost of treatment, however comparison of the two
technologies is less well defined. Since the cost of UF treatment is largely
dependent on flux, it will be necessary to evaluate UF systems on a full-scale level.
At this time there has been no long-term operation of a UF system at an actual
laundry.
7.1.3.4 Diatomaceous Earth Filtration
Diatomaceous earth (DE) filters have been applied to treatment of laundry
wastewater. In DE filtration a thin layer of precoat is formed on a porous septum in
order to strain out suspended solids in the effluent (27). A cake is formed on the
filter by deposition of suspended solids and DE, which is added to the effluent at a
constant rate. Head loss through the cake increases as filtration progresses; reverse
water flow is initiated when a preset maximum head loss is reached. Generally, DE
filtration is capable of excellent, removal of suspended solids but not of colloidal
matter (27).
Treatment of wastewater at a linen supply laundry was accomplished by DE
filtration. Effluent from an equalization tank was injected with DE and a
proprietary oil adsorbent, then pumped through precoated pressure filters. The
system provided moderate removal rates, 32 percent BOD, 65 percent TSS, 43
percent oil and grease and 40 percent metals. The system, although once in
fullscale operation, it has since been replaced by a treatment system using calcium
chloride coagulation and DAF.
7.1.3.5 Electrocoagulation
An electrocoagulation (EC) process has been pilot tested on a laundry waste-
water. In EC, an electric current is continuously conducted through a tank
functioning in a plug-flow mode. Current is provided by electrodes immersed in the
wastewater. EC system are designed to treat laundry wastewater through two
mechanisms. With the first, electrolysis induces coagulation by neutralizing or
95
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imparting a positive charge to negatively charged colloidal material. With the
second, microbubbles formed as a result of electrolysis float the resulting floe to
the surface of the contained effluent where it can be skimmed off (30).
In the pilot tests chemical addition was required prior to electrolysis to
achieve removal of incompatible pollutants. Alum, sulfuric acid, and polymer were
added. Removal rates included 80 percent oil and grease, 53 percent BOD and TS5,
and ^5 percent metals. ,
Theoretically, EC processes are capable of performing both coagulation and
floe flotation. In practice, however, chemical addition of the type described for
physical-chemical treatment is necessary to achieve an effluent quality comparable
to that achieved by presently applied technologies.
7.1.3.6 Other Technologies
Other treatment technologies have been laboratory or pilot tested on laundry
wastewaters with varying degrees of success. These technologies include reverse
osmosis, foam separation, distillation, and carbon adsorption (22, 31-33). In general,
these techniques were found either not applicable to removal of pollutants found in
laundry wastewater or are considered not economically comparable to technologies
previously described.
The use of carbon adsorption and steam stripping technologies following DAF
treatment was investigated specifically for the further removal of toxic organics.
Steam stripping was not considered technologically viable because of the boiling
point characteristics of many of the toxic organics found in laundry wastes.
Although volatile and semivolatile organics would be substantially removed by
stripping, organics with high boiling points, i.e., phthalates would not be reduced.
Carbon adsorption following DAF was also not considered technologically feasible
due to the characteristics of DAF effluent. Oil and grease levels found in typical
DAF effluents are sufficiently high that'a filtration step would be required prior to
carbon adsorption to prevent fouling of the carbon.
7.1.* Space Availability
Since laundries may have limited additional space for treatment equipment, it
is important to note the space required for PCS's. Average space requirements for
physical-chemical treatment by DAF are presented in Table 7-5 for selected
effluent flowrates. Chemical addition and floe removal equipment are the essential
hardware required; equalization tanks are assumed below .grade.
A site survey of b5 industrial laundry sites concluded that space is generally
available for the installation of treatment equipment. Less than 10 percent of
facilities would have major problems installing equipment. The costs associated
with space allocation were estimated from the survey. These costs were included in
site preparation charges as a part of capital costs presented in Section 8.
7.2 TREATMENT FOR DIRECT DISCHARGE
As indicated in Section 5, an extremely limited number of laundries are direct
dischargers. Only one linen supply laundry is known to be a direct discharger. No
96
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TABLE 7-5 AREA REQUIREMENTS FOR PCS's
Exemplary flowrate,
m3/day (gal/day)
570
380
280
190
38
19
(150,000)
(100,000)
(75,000)
(50,000)
(10,000)
(5,000)
Required area
for system,
m2
-------
industrial laundries are known to be direct dischargers. A survey of the industry
identified 23 coin-operated laundries and one institutional laundry (with a workload
similar to that of a power laundry) that operate wastewater treatment systems.
Thus, technical data on the performance of laundry wastewater treatment systems
(other than the pretreatment systems discussed in the preceding subsection) are
quite limited. Hypothetical treatment systems for the direct discharge of linen
supply and industrial laundry effluents are described in the following subsections.
7.2.1 Primary Treatment
Pollutants typically found in laundry wastewater are identified in Section 5 of
this report. Based on information provided there, pollutants which may require
control before direct discharge include oil and grease, pH, BOD, TSS, lead, copper,
chromium, and zinc. Treatment technologies capable of controlling these
parameters are classified as either physical-chemical or biological.
A previous study has concluded that biological systems cannot effectively
treat industrial strength laundry wastewater (17). One possible explanation for this
ineffectiveness is the inability of biological systems to cope with high concen-
trations of oil and grease, which may be found in linen supply and industrial laundry
effluents (see Section 5). Studies have indicated that systems incorporating
trickling filters or activiated sludge can effectively treat effluents with emulsified
oil concentrations of 100 mg/1 or less (34, 35). Median oil and grease concentrations
found in linen supply and industrial laundry wastewaters were 300 mg/1 and 720
mg/1, respectively. Microbial metabolism, a primary mechanism for pollutant
removal by biological systems, may be inhibited by oily materials due to the low
solubility of oil, the chemical configuration of oil molecules, and the nature of
microbial surface (36).
Since biological systems are limited in their capability, two stages, primary
and secondary treatment systems may be considered necessary for linen supply and
industrial laundry effluents being directly discharged. Noting the removals of
pollutants for pretreatment DAF is considered an effective primary treatment
technology and is used as the basis for primary treatment prior to direct discharge.
7.2.2 Secondary Treatment
/
Considering the pollutant concentrations shown in Appendix C for wastewater
after physical-chemical treatment, secondary treatment may be required before
linen supply and industrial laundry effluents can be discharged to surface waters.
Biological techniques are considered' suitable for secondary treatment of these
effluents. This assumption is based on limited performance data from coin-operated
laundries currently operating small-scale biological units.
7.2.2.1 Biological Treatment
Two biological units, trickling filters and facultative lagoons, are considered
for potential secondary treatment of laundry effluents. Selection of this particular
equipment is mainly based on survey information from coin-op laundries. A general
characterization of industrial and/or linen supply laundry wastewater after primary
treatment is given in Table 7-6. The indicated BOD loading of 300 mg/1 was used
98
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TABLE 7-6 CHARACTERIZATION OF LAUNDRY
WASTEWATER AFTER PHYSICAL-CHEMICAL TREATMENT
Estimated
concentrations3
after P-C
treatment,
Pollutant
Oil and grease
BOD5
TS5
Phosphorus
Copper
Lead
Zinc
PH
mg/L
70
300
100
0.*
0.2
0.1
0.4
7.0
Median concentrations are taken from
Section 5,
99
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for developing design parameters for biological systems incorporating either
facultative lagoons or trickling filters.
Wastewater from primary treatment is considered similar to raw wastewater
from coin-op laundries (see Table 5-8). Since certain parameters such as BOD are
somewhat higher for primary treated wastewater, the biological system for linen
supply and industrial laundries must be designed accordingly.
Stabilization Pond - An aerobic/anaerobic (facultative) stabilization pond
(lagoon) has been considered for secondary treatment of laundry wastewater. In this
system, surface aerators are used to mix the effluent in the upper portion of the
lagoon. Oxygen supplied to this area from aerator action is used by aerobic
microorganisms for metabolic waste conversion and BOD reduction. Incoming solids
and solids (microorganism cell tissue) formed during conversion settle to the lower
region of the lagoon where anerobic decomposition occurs, resulting in further BOD
reduction. Final effluent from this type of lagoon is generally more highly
stabilized than effluent from completely aerobic systems (23).
Table 7-7 presents effluent concentration data for three lagoons operated by
coin-op laundries. These data were taken from NPDES monitoring reports, and no
influent concentration data were available. Thus, the data serve only as relative
indicators of achievable effluent quality (in terms of BOD^, suspended solids,
phosphorus, and oil and grease).
Tricking Filters - Trickling filters are also considered viable secondary
treatment. A trickling filter consists of a circular basin filled with permeable
media to which microorganisms are attached and through which the laundry effluent
is percolated (23). The filter medium may consist of plastic chips or rocks; the
effluent is distributed over the top of the media by means of a rotary distributor
(23).
Microorganisms attached to the filter medium degrade the organic material
present in the wastewater, resulting in an initial reduction in effluent BOD. Solids
formed during filter action are carried with the percolating effluent through the
underdrain to a settling tank. Settling of solids in the tank is an additional
mechanism for BOD reduction.
Survey data showing the reduction of various pollutants by trickling filter
systems are given in Table 7-8 for two coin-op laundries. Average flowrate for one
laundry is 15 m^/day (4,000 gpd); flowrate for the other laundry is not available
from survey data.
7.2.2.2 Other Technologies
Secondary, treatment of laundry wastewater by carbon adsorption has been
tested on a pilot scale. Effluent from the UF unit described in Section 7.1.3 was
continuously directed through a carbon column during testing procedures. Removal
of dissolved organics by activated carbon occurs through adsorption, a process where
physical and chemical attractive forces bind organic molecules to a highly porous
carbon surface. Generally, low molecular weight or highly soluble organics are less
readily removed from wastewater by carbon than organics of low solubility and/or
high molecular weight.
100
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TABLE 7-7 EFFLUENT CONCENTRATIONS FOR LAGOONS
TREATING WASTEWATER FROM COIN-OP LAUNDRIESa
Pollutant
Parameter
BOD5
TSS
pH
Phosphorus
Oil and grease
Number of
data points
10
10
5
1
1
Median
effluent
concentration,
mg/1
20
83
9.3
0.02
2.5
Range
mg/1
1 - 130
1* - 273
8 - 9.9
--
—
a Data are from three coin-op laundries; average effluent flow
rates were reported as 3 m^/day (770 gpd), 5.7 m^/day (1,500
gpd), and 25 m3/day (6,500 gpd).
101
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Limited performance data developed during a two-week pilot-scale test of
activated carbon treating laundry wastewater from a UF unit (14) showed that
carbon did not further reduce BOD concentrations. Thus, activated carbon is not
considered as applicable for secondary treatment.
7.3 RECYCLE/REUSE TECHNOLOGY
Due to the rising costs of fuel and water incurred by laundry facilities, a few
operators are presently reusing or recycling their wastewater. For purposes of
discussion, reuse is defined as the use of untreated wastewater in a second
application that is different from the orginal. Recycle is defined as the treatment
of laundry wastewater by physical-chemical means enabling it to be used again in
the washing process. Both reuse and recycle techniques are discussed in the
following sections.
Reuse - In reuse strategies, laundry wastewater from one or more rinse cycles
is introduced into the wash process in the initial flush, break, and/or suds cycles.
Holding tanks are used for storage of rinse waters until a subsequent laod of laundry
is ready for washing. Fresh water is added to the rinse water in amounts that
provide an adequate quality of water for use in a preliminary wash stage. A laundry
operator will typically arrange his loads so that wastewaters from lightly soiled
articles can be reused on more heavily soiled loads. Before reuse, wastewaters may
be treated by conventional techniques such as lint screens or catch basins.
Recycle - In order to recycle an equalized flow of laundry wastewater,
physical-chemical treatment techniques are employed to achieve a water quality
acceptable for use as a washing medium. Quality specifications are difficult to
define since laundry personnel are not in agreement as to what constitutes
acceptable water quality, or the means of achieving such quality. Laundry
wastewater recycling is a comparatively new concept; only a very small number of
laundries (approximately 7) are practicing effluent recycle. Thus it is difficult to
determine the technical feasibility of effluent recycle on a large scale.
Two physical-chemical treatment systems are currently being used for laundry^
wastewater recycle. These systems use alum or polyelectrolyte for chemical'
coagulation, followed by dissolved air flotation and filtration for floe removal.
Treated effluent is usually stored in an insulated holding tank and pumped to
the washing machines as required. Recycled water is mixed with fresh water before
being used in the wash process. In present applications, 60% to 80% of this mixture
is recycled to keep dissolved vsolids concentrations at an acceptable level as part of
achieving the overall water quality necessary for laundering. Laundries with these
recycle systems report that the treated water is acceptable for recycle purposes so
long as the necessary dilution is provided. -•
•Recycle of industrial-strength laundry effluent is being practiced at only one
or two facilities with prototype treatment units. Therefore, the technical
feasibility of laundry effluent recycle on an industry-wide basis has not been proven.
Potential technical problems involving recycle which may require further
consideration are listed below:
103
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o Specific contaminants such as dyes and soivents may render the treated
effluent unacceptable for recycle.
o Increased concentrations of dissolved solids in recycle water may render
it unsuitable for certain laundering applications unless high dilution
ratios are used. Higher dilution ratios reduce the economic
attractiveness of recycling.
o Influent streams to recycle systems generally contain higher pollutant
loadings than influents to once-through treatment systems employing
similar treatment technology. This observation was made by one recycle
system manufacturer contacted during this study. Recycle systems, thus
may not achieve the effluent quality possible with once-through systems
when treating comparable strength effluents.
7A SLUDGE HANDLING AND DISPOSAL
Solid waste (sludge) is produced as a result of physical-chemical and/or
biological treatment of laundry wastewater. In a DAF system, floe formed by
coagulation is collected in the DAF unit, resulting in a sludge having a solids content
of 5% to 8% by weight. This sludge is composed of coagulant chemical precipitates
and pollutants removed from the wastewater. Biological sludges result from
microbial growth and decay. In the following section only solid waste from DAF is
discussed because no information was available on sludges resulting from the
biological treatment of laundry wastewater.
7.4.1 Sludge Dewatering
Sludges from DAF units are typically in a liquid state with a solids content of
5% to 8% by weight. Dewatering techniques serve to reduce the overall volume of
solid waste produced, converting sludge into a more solid form. Dewatering will
usually make handling and disposal of sludges easier and less costly for the laundry
operator. Certain laundries with DAF currently use rotary vacuum filters or screen
presses for dewatering purposes. A sludge cake with a solids content of between
20% and 30% is produced with these devices.
7.4.1.1 Rotary Vacuum Filters
A vacuum filter consists of a cylindrical rotating drum partially submerged in
a vat of sludge. Sludge adheres to a cloth or steel mesh filter that makes up the
drum surface. Vacuum imparted to the inside of the rotating drum draws water
from the sludge through the filter material to the drum interior where it collects
and is either discharged as final effluent or directed back to the equalization tank.
The resulting dewatered sludge (filter cake) is scraped from the filter and collected.
The ability of a rotary filter to dewater laundry sludge depends on the
following conditions:
o Type and concentration of contaminants in the laundry effluent being
treated,
104
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o Type and quantity of chemicals used for physical-chemical treatment,
and
o Design capabilities of the dewater ing equipment.
Laundries currently employing rotary filters report sludge cakes having
between 20% and 30% solids by weight. In instances where laundry effluents have
high solvent concentrations it has been reported that the resulting sludges are
relatively more difficult to dewater by rotary vacuum filtration.
7AA.2 Screw Presses
A screw press is used at one commercial laundry to dewater sludge from a
DAF unit. Before entering the press, sludge is conditioned by addition of a polymer
that chemically alters its characteristics, enhancing separation of water from solid
material. A rotating screw acts to compress the incoming sludge, squeezing out
water; the resulting sludge cake is approximately 20% solids by weight.
7.4.2 Sludge Quantity
The amount of sludge produced as a result of DAF treatment of laundry
wastewater was estimated to determine the sludge disposal costs given in Section 8.
Based on the median concentrations of oil and grease and TSS in industrial laundry
effluents, before and after treatment, it was assumed that a 90% reduction in these
parameters was typical for a DAF. This assumption and respective coagulant feed
rates of 1,200 mg/1 and 1,800 mg/1 for industrial laundry wastewaters were used to
calculate sludge production. Solids content in sludge from a DAF unit was assumed
to be 5% solids by weight. Table 7-9 gives the production of DAF sludge and
dewatered sludge at various flowrates for industrial laundries.
7A.3 Disposal Techniques
Most laundries operating DAF systems employ the services of an outside
contractor for disposal of sludge. The contractor may use a sanitary landfill or an
incinerator to achieve final disposal. It is reported from site surveys that present
contractors predominantly use sanitary landfills for final disposal of laundry sludges.
However, if laundry sludge is found to be hazardous as defined by the Resource
Conservation and Recovery Act (RCRA), then the sludge must be disposed of in
RCRA approved landfills.
105
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TABLE 7-9 SLUDGE QUANTITIES RESULTING FROM THE PHYS1CAL~CHEMICAL
TREATMENT OF INDUSTRIAL LAUNDRY WASTEWATER a
Sludge Production
from DAF unit"3
kg/day m^/day
(Ib/day) (yd3/day)
2,300 (5,000)
1,400 (3,120)
680 (1,500)
400 (875)
170 (375)
57 (125)
12 (50)
46 (60)
28 (37)
14 (18)
7.6 (10)
3.4 (4.5)
1.1 (1.5)
0.5 (0.6)
De watered
sludge b
m^/day
(yd3/day)
i
9.0 (12)
6 (8)
3 (4)
1.5 (2)
0.8 (1)
0.2 (0.3)
0.07 (0.1)
a Based on sludge solids content of 5% by
weight.
b Based on sludge solids content of 25% by
weight.
106
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SECTION 8
COSTS OF TREATMENT SYSTEMS
This section presents capital and annual cost estimates for treatment of
laundry wastewater. The treatment technologies selected tfor cost estimation
purposes are briefly reviewed. Capital and annual cost estimates for pretreatment
and direct discharge treatment of laundry wastewaters are presented in graphic and
tabular form. Selected flowrates based on industry data are used in the tables. Jhe
costs are in fourth quarter, 1978 dollars. The basis for capital and annual costs for
each component system is presented. Energy, sludge management, air pollution and
other nonwater quality environmental considerations are addressed.
Technologies for pretreatment and direct discharge treatment of laundry
wastewaters were discussed in Section 7. Technologies presently applied in the
laundries industry were selected for cost estimation purposes. Dissolved air
flotation (DAF) treatment was described as applicable technology for pretreatent of
laundry wastewaters. In addition, DAF plus biological treatment was described as
applicable technology for direct discharge treatment of laundry wastewater. The
DAF treatment systems considered incorporate chemical addition and floe-removal
techniques to remove pollutants. Trickling filters and stabilization ponds were the
biological treatment systems considered. Pollutant removal capabilities of DAF and
biological treatment systems were discussed in Section 7.
Differences in pollutant loadings affect operating costs but not capital costs
of DAF treatment systems; in addition they affect capital costs of treatment for
direct discharge. Typical pollutant loadings, as found in industrial laundries, were
used for cost estimation purposes.
8.1 CAPITAL AND ANNUAL TREATMENT COSTS ESTIMATE SUMMARY
Table 8-1 presents treatment technologies considered for cost estimation
purposes for the pretreatment and the direct discharge treatment of laundry
wastewaters. These technologies are DAF treatment for pretreatment, and DAF
plus biological treatment (either a stabilization pond or a trickling filter) for direct
discharge. These treatment systems are combinations of various alternatives that
affect capital costs, such as type of biological system.
Table 8-2 presents and summarizes, for selected flowrates, capital and annual
cost estimates for the pretreatment of laundry wastewater with DAF. Figure 8-1
graphically presents total capital cost estimates versus flowrate while Figure 8-2
presents total annual costs versus flowrate for the pretreatment of laundry
wastewaters. Data points shown in the figures were developed from vendor quotes
and estimates for various flowrates.
107
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TABLE 8-1. TREATMENT OPTIONS FOR LAUNDRY WASTEWATERS
Pretreatment Direct Discharge treatment
System
Physical-
chemical
Option Systems
DAF , Physical-
chemical
plus
biological
Options3
(Physical-
chemical system
using DAF) plus
trickling filter or
stabilization
pond.
Options are combinations of various alternatives that affect capital costs.
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Table 8-3 presents and summarizes, for selected flowrates, capital and annual
cost estimates for the direct discharge treatment of wastewaters with DAF and
either a stabilization pond or a trickling filter. Figure 8-3 presents graphically total
capital cost estimates versus flowrate while Figure 8-4 presents total annual cost
estimates versus flowrate: Total annual costs and total capital costs differ
significantly between DAF treatment with stabilization ponds and trickling filters
because of the significant differences between the capital and annual costs between
stabilization ponds and trickling filters.
8.2 COST BASIS
Total capital cost estimates include equipment costs, freight charges, site
preparation costs, installation costs, indirect charges for engineering and
construction, startup costs, and contingency allowance. Estimates do not include
allowances for working capital. Working capital costs will be insignificant because
large "product" and raw material inventories are not maintained.
Capital costs estimates were developed separately for DAF
systems and biological treatment systems.
treatment
All costs are given in fourth quarter 1978 dollars. Costs are based on
information, quotes, and estimates from vendors, industry associations, and the
literature. The data were aggregated and averaged where possible.
8.2.1 Dissolved Air Flotation Treatment Systems
A DAF treatment system was selected for cost estimation as the pretreatment
system for laundry wastewaters discharged to POTW's and as part of the treatment
system for the direct discharge of laundry wastewaters to receiving waters. The
DAF treatment system considered incorporates chemical addition and floe-removal
techniques to remove pollutants.
8.2.1.1 Capital Cost Estimate
Capital costs include equipment costs, freight charges, site preparation costs,
installation costs, indirect charges for engineering and construction, start-up
charges, and a 10% contingency allowance. The allowance was used to cover
potential price increases, construction delays, and other unforeseen expenses.
Allowance for working capital was not included because it will be insignificant.
The data points were determined using vendor-supplied quotes and estimates
for equipment, freight, installation, and start-up expenses. These vendors specialize
in treatment systems for laundries, and the majority of the systems offered are
turnkey systems or packaged, skid-mounted systems. Therefore, no component cost
breakdown (such as equipment, piping, installation, engineering, etc.) is possible
because of the nature of the quotes and estimates used.
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3.2.1.2 Annual Treatment Cost Estimates
Annual costs include amortization, operating, maintenance, insurance,
monitoring, and technical support charges.
Amortization - The annual amortization was determined from the total capital
cost estimate using the following equation:
Annual amortization, $/yr = CRF x A
where CRF = capital recovery factor, 0.163 (86)
A = capital cost estimate, $
(8-1)
A 10% annual interest rate, 10-year equipment life, and no salvage value were
assumed.
Chemical Costs - Chemical dosage rates for various systems of chemical
additives were evaluated following input from industry. These rates along with
literature sources (57), chemical supply vendors' estimates, treatment system
vendors' estimates, and chemical costs for systems in operation at laundries were
aggregated to produce a range of chemical costs, from $0.063/m3 of water treated
to $0.4-3/m3 of water treated ($0.24/1,000 gal. of water treated to $1.62/1,000 gal.
of water treated).
The most significant factor in determining the range of chemical costs was the
variations in the cost per kilogram (pound) or cubic meter (gallon) of the chemical to
be used. Therefore, local prevailing prices for chemicals will affect the chemical
cost per unit of water treated more significantly than will the system of chemical
additives chosen.
The average chemical costs of $0.28/m3 of water treated ($1.05/1,000 gal. of
water treated) were developed by averaging the chemical costs incurred by
industrial laundries and linen supply laundries, respectively, having DAF treatment
systems.
Figure 8-5 presents the relationship between annual chemical costs and
flowrates for the DAF treatment of laundry wastewaters. Based on laundry industry
data, 260 operating days/year are used to calculate annual charges.
Sludge Disposal Costs - Sludge disposal costs include the cost for the removal
of the sludge from laundry premises and the hauling of sludge to an approved
landfill. The sludge may or may not be dewatered depending on the economics of
dewatering. Disposal may or may not be performed by contract labor. Costs were
compiled from estimates and costs provided by the laundries industry, costs incurred
by laundries operating DAF treatment systems, and the literature (58).
Costs for sludge disposal range from $0.018/m3 of sludge to $65/m3 of sludge
($0.014/yd3 of sludge to $50/yd3 of sludge) with an average cost of $7.80/m3 of
sludge ($6/yd3 of sludge).
Daily sludge generation rates are presented in Figure 8-6. The information
was developed in Section 7. Dewatering of sludge to reduce volume, and therefore
disposal charges, will be economical when the annual savings from the reduced
116
-------
203 250 300 430450500 SCO 700 300
(200)
FLO WRATH, m/day
Figure 8-5. Annual chemical costs for DAF treatment of laundry
wastewaters.
117
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(20)
(40) (60) (80) (100) (200)
J I
II 111
20
50
100
150 200 250 300 400450500600700800
FLOWRATE,m3/day(103gpd)
Figure 8-6.
Daily sludge generation rates for DAF treatment of
laundry wastewaters.
118
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volume of sludge for disposal equals or exceeds the annual amortized cost of
dewatering equipment. This will be the lowest economical flowrate for sludge
dewatering. Labor and maintenance charges are not specifically quantifiable from
the estimates supplied by the laundries having these treatment systems. Graphing
the annual amortized equipment costs and the annual disposal charge savings for
dewatered sludge shows that sludge dewatering becomes economical at 64 m^/day
(17,000 gpd), as shown in Figure 8-7. Based on laundry industry data, 260 operating
days/year are used to calculate annual costs.
Figure 8-8 presents annual sludge disposal cost estimates versus flowrate for
the DAF treatment of laundry wastewaters. The average cost for sludge disposal is
$0.48/m3 of water treated ($1.80/1,000 gal. of water treated) for sludge not
dewatered and $0.094/m3 of water treated ($0.36/1,000 gal. of water treated) for
dewatered sludge from treatment of heavy pollutant loading laundry wastewaters.
The average cost for sludge disposal is $0.27/m3 of water treated ($1.00/1,000 gal.
of water treated) for sludge not dewatered and $0.054/m3 of water treated
($0.21/1,000 gal. of water treated) for dewatered sludge from treatment of medium
pollutant loading laundry wastewaters.
Electricity Costs - Electricity costs were developed from costs reported by
laundries operating DAF treatment systems. Electricity costs averaged $0.03/m^ of
water treated ($0.13/1,000 gal. of water treated), and the range is from $0.021/m3
of water treated to $0.066/m3 of water treated ($0.08/1,000 gal. of water treated to
$0.25/1,000 gal. of water treated).
Operating Labor Charges - Annual operating labor charges for DAF treatment
systems were developed from man-hour requirements and wage rates supplied by
laundries operating such treatment systems. Daily labor requirements were
estimated as 4 hours/day. Based on laundries industry data, 260 operating days/year
were used to calculate annual costs. An average, fully-burdened wage rate for
treatment system operators in the laundries industry is $15/hr.
Annual labor charges are estimated to be $16,000 for the DAF treatment of
laundry wastewaters and are independent of flowrate (total was rounded).
Maintenance Charges - Maintenance costs were estimated to be 2% of the
capital cost of DAF treatment systems.
Insurance Charges - Insurance charges were estimated to be 1% of capital
costs of DAF treatment systems.
Monitoring Charges - Monitoring charges include outside laboratory analysis
charges and costs for reporting results to regulatory agencies. The costs associated
with the collection and delivery of samples are included in the operating labor
estimates.
Monitoring for indirect dischargers (dischargers to POTW's) was assumed to be
necessary six times per year. Analytical charges were assumed to be $65 per
occasion. Four hours per occasion of management time were estimated at $30/hour.
Annual monitoring charges are estimated as $1,100 for the DAF treatment of
laundry wastewaters; this is independent of fiowrate.
119
-------
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;"80
60
40
20
10
8
6
4
S 2
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0.8
0.6
0.4
0.2
0.1
(1)
DISPOSAL
SAVINGS
FOR
DEWATERED
SLUDGE
AMORTIZED COST OF /
SLUDGE DEWATER ING
FLOWRATES ABOVE WHICH
SLUDGE DEWATER ING IS
ECONOMICALLY JUSTIFIED
' i > i i i t
t I I I I I L
(2)
(4) (6) (8) (10)
(20)
(40) (60) (80) (100) (200)
50
100
ISO 200 250 300 *0«0500600n»800
aOWRATE, m3/day (lo'gpd)
Figure 8-7
Annual sludge disposal savings for dewatered
sludge versus annual amortized cost of
sludge dewatering equipment.
120
-------
100
60
40
20
10
8
6
4
8
1
as
0.6
0.4
0.2
0.1
(1)
WITHOUT
DEWATERING
FLOWRATES WHERE THE
ANNUAL AMORTIZED
COST OF SLUDGE
DEWATERING EQUIPMENT
EQUALS THE SAVINGS IN
YEARLY DISPOSAL COST
(SEE PREVIOUS FIGURE)
THEREFORE ECONOMICALLY
JUSTIFY ING THE USE OF
SLUDGE DEWATERING
WITH
DEWATERING
' i i i » i i
_L
» i I I
(2)
(4) (6) (8) (10)
(20)
(40) (60) (80) (100) (200)
i i
iii i i j
20
50
100
150 200 250 MO 400450500 600700 800
FLOWRATE, m3/day (rfgpd)
Figure 8-8. Annual sludge disposal3 costs for.DAF treatment of
laundry wastewaters.
Only sludge disposal costs are shown on graph.
ing equipment cost not included.
Sludge dewater-
121
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Technical Support - Troubleshooting, fine tuning, and adaptation of the
treatment system to changing wastewater characteristics caused by changes in
laundry product mix will have to be performed for the life of the treatment system.
These services may be supplied by the equipment vendor, the chemical supply
vendor, in-house personnel, or a consulting firm. The cost is, therefore, highly
variable ranging from zero dollars paid for the service, if it is performed by
employees in addition to their other duties, to perhaps 5% to 10% of the capital
cost.
Technical support costs were estimated to be $6,000 annually for DAF
treatment of laundry wastewaters; this is independent of flowrate.
Summary of Annual DAF Treatment Cost Estimates - Table 8-4 summarizes
the annual cost for the DAF treatment of laundry wastewaters.
8.2.2 Biological Treatment Systems
Biological treatment systems were selected for cost estimation as part of the
direct discharge treatment technology for laundry wastewaters. Biological and DAF
treatment together comprise the direct discharge treatment for laundry
wastewaters.
Trickling filters and aerobic-anaerobic stabilization ponds were the biological
systems selected.
8.2.2.1 Trickling Filters
8.2.2.1.1 Capital Cost Estimate
»
Capital costs include equipment costs, freight charges, installation costs,
indirect charges, start-up charges, and contingency. Working capital is not included
because it is insignificant.
Major equipment component costs, such as filter media, rotary distributor,
underdrain material, containment panels, holding tank, and clarification tank were
obtained from vendors. The delivered, installed cost of' this equipment was
multiplied by a factor of 1.75 to estimate the additional piping, instrumentation,
start-up, indirect, and contingency charges for an add-on system to the physical-
chemical treatment system. A factor of 2.00 was used to estimate the total capital
cost of an independent treatment system. Figure 8-9 illustrates the capital costs
versus flowrate relationship for the trickling filter treatment of laundry
wastewaters.
8.2.2.1.2 Annual Cost Estimate
Amortization - Annual costs for trickling filters include amortization,
operating, maintenance, and insurance charges. Figure 8-10 illustrates the
relationship between annual costs and flowrates. The annual amortization was
determined using Equation 8-1 with capital recovery factor equal to 0.117 (62). A
10% annual interest rate, 20-year equipment life, and no salvage value were
assumed.
122
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TABLE 8-4 SUMMARY OF ANNUAL TREATMENT COST ESTIMATES FOR
DAF TREATMENT OF LAUNDRY WASTEWATER
Component costs
Annual cost
Amortization
Chemicals
Sludge disposal, dewatered
Sludge disposal, undewatered
Electricity
Operating labor
Maintenance
Insurance
Monitoring
Technical support
0.163 (capital cost)
($0.28/m3)a(flow)b
($0.094m3)c(flow)b
($0.48/m3)d(flow)b
($0.03/m3)e(flow)b
$16,000
0.02(capital cost)
0.01 (capital cost)
$1,100
$6,000
a Range of $0.063/m3 of water treated to $0.43/m3 of water treated.
k Flow equals m3/day times 260 operating days/year.
c Range of $0.00012/m3 of water treated to $0.45/m3 of water treated and
$0.00022/m3 of water treated to $0.78/m3 of water treated, respectively.
d Range of $0.00061/m3 of water treated to.$220/m3 of water treated, and
$0.001 l/m3 of water treated to $4.00/m3, respectively.
e Range of $0.02 l/m3 of water treated to $0.066/m3 of water treated.
f Range of $0.032/m3 of water treated to $0.32/m3 of water treated.
g Range of $0.008/m3 of water treated to $0.49/m3 of water treated.
n Range up to $0.87/m3 of water treated.
123
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Operating, Maintenance, and Insurance Charges - Operating, maintenance, and
insurance (OMI) charges were estimated as 6% annually of the trickling filter capital
cost based on literature sources (59,60).
8.2.2.2 Aerobic-Anaerobic Stabilization Ponds
8.2.2.2.1 Capital Cost Estimate
Capital costs include the items previously discussed. The costs of major
components such as aerators, concrete work, pond liner, excavation, and a
chlorinator were obtained from vendors. The cost of these items was multiplied by
a factor of 2.00 for an add-on to DAF treatment, and by a factor of 2.25 for an
independent system to estimate additional charges for piping, instrumentation,
installation, indirects, etc. Figure 8-11 illustrates the capital cost versus flowrate
relationship.
8.2.2.2.2 Annual Cost Estimate
Annual costs of stabilization ponds versus flowrates are illustrated in Figure
8-12.
Amortization - The annual amortization was determined using Equation 8-1
with capital recovery factor equal to 0.117. A 10% annual interest rate, 20-year
equipment life, and no salvage value were assumed.
Operating, Maintenance, and Insurance Charges - Operating, maintenance, and
insurance charges were estimated as 10% of the stabilization pond capital cost
based on literature sources (60,61).
8.3 ENERGY CONSUMPTION
The total annual electricity consumption for pretreatment in the subcategories
for which pretreatment may be necessary, industrial laundry and linen supply
subcategories, was estimated and is presented in Table 8-5. The electricity usage
per cubic meter of water treated (per 1,000 gal of water treated) was determined
from the cost of electricity for pretreatment ($0.13/1,000 gal as previously
developed) and an estimate of the average unit cost for electricity ($0.04/KWH).
An estimate for the electricity consumption in both subcategories from an
industry trade association is 80 M3/kg of laundry (10 KWH/100 Ib of laundry). Using
the same information, estimates of electricity consumption were developed and are
presented in Table 8-6. The increase in electricity usage if all laundries were to
install pretreatment systems (and none presently had them) is also estimated. The
increase in electricity consumption in industrial laundries and linen supplies would
be 20% and 17%, respectively.
Of course, these estimates are only crude approximations of the actual
increases in electrical consumption that would be incurred if all industrial laundries
and linen supplies were to install pretreatment systems. It is also important to note
that these percent increases apply to electrical power only, and not to total energy
consumption (which includes fuel for steam generation).
126
-------
pi.S
S J
CM -
S -
I I t i I I t I
O
CM
CO
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o
erf
S S
<*\ CM
8
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O
a. •
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ra
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127
-------
00
CO
o
o
100
80
60
40
20
10
8
6
INDEPENDENT
SYSTEM
i i i i i i t
JL !_J_J_J_L-L
(1)
(2) (3) (4) (6) (8) (10)
(20)
(40) (60)(80)(100) (200)
JL
JL
J_
t _i I I II
20
50
100
150 200
300 «D 45050060)700 800
FLOVVRATE,rn3/day(103gpd)
Figure 8-12.
Total annual costs for stabilization pond
treatment of 'laundry wastewaters.
128
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TABLE 8-5. ANNUAL ELECTRICITY CONSUMPTION
BY PRETREATMENT
Approximate
number of
indirect
Subcategory dischargers
Annual electricity
consumption by
treatment,
PJ (106 KWH)
Electricity usage
per 1,000 gal of
water treated,
MJ(KWH)
Industrial
laundry
Linen
supply
1,000
1,300
0.23
. 0.55 (150)
12 (3.3)
12 (3.3)
129
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TABLE 8-6. ANNUAL ELECTRICITY CONSUMPTION
AT LAUNDRIES
Subcategory
Industrial
laundry
Linen supply
Number of
indirect
dischargers
1,000
1,300
Annual
consumption
PJ/y (106 KWH/y)
1.2 (320)
3.2 (890)
Increase in
consumption
if pretreatrnent
technology used,
percent
20
17
130
-------
8.* SLUDGE'MANAGEMENT
Present sludge disposal practices consist of contracting with a hauler/landfill
operator to provide for disposal. The sludge may or may not be dewatered before
disposal. Presently, screw presses and vacuum filters are used to dewater sludge.
The quantities of sludge generated per year by pretreatment are estimated in Table
8-7, assuming all laundries installed these systems and none presently had them, and
that all sludge is either dewatered or all is not dewatered. Using the amount of
sludge generated per 1,000 gallons of water treated, the average number of gallons
of water used per laundry per year, and the number of indirect dischargers in the
subcategory, the amount of sludge generated per year for subcategories in which
pretreatment may be necessary was estimated.
New developments in sludge handling practices are underway in the Chicago
area. Recent legislation has required that the generation and disposal of industrial
waste be monitored by a set of forms (manifests). Monitoring is required from the
time of sludge generation to its ultimate disposal, and copies of the forms are
provided to each handler and to the sanitary district at each step. The system has
not been in effect for a time sufficient to permit the assessment of costs incurred
by industry.
The sludge composition is discussed in Section 7 and corresponds to pollutants
removed from the laundry wastewater plus additive chemicals.
8.5 OTHER NONWATER QUALITY ASPECTS
Presently, there are no other known, significant, nonwater quality
environmental impacts in terms of noise, radiation, or health from the selected
treatment technologies.
The nonwater quality aspects relating to air pollution that do not concern just
the automatic and other laundries industry are 1) a possible stripping of volatile
toxic pollutants in the treatment systems, and 2) release of air pollutants from
sludge incineration. Release of volatile toxic compounds by stripping is
theoretically possible, but it has not been measured at this time. The possible
impact on air quality has not been evaluated. The second aspect to be considered is
the release of air pollutants, especially heavy metals, as participate or vapor if the
sludge produced from laundry wastewater treatment is incinerated. This is not
presently practiced as a disposal method, and the possible air quality impact has not
been evaluated. »
131
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TABLE 8-7 AMOUNT OF SLUDGE GENERATED PER YEAR BY
PRETREATMENT
Subcategory
Number of
indirect
dischargers
Sludge generated
m^/m3 of water
treated (yd3 1,000
gal. of water
treated
m
3/yr
Industrial
laundry
Linen
supply
1,000
1,300
0.061*
(0.30)
0.012k
(0.060)
(0.17)
0.0069b
(0.034)
4.5
(6.0)
0.91
(1.2)
6.2
(8.1)
1.2b
(1.6)
aSludge not dewatered.
^Sludge dewatered.
132
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SECTION 9
SELECTION OF APPROPRIATE CONTROL AND TREATMENT TECHNOLOGY
AND BASIS FOR LIMITATIONS
In the industrial laundry and linen supply subcategories all plants but one are
known to discharge to POTWs. Based on the characteristics of wastewater
generated by these two subcategories and the potential for toxic pollutants to pass
through POTW systems, the Agency has deemed it necessary to propose
pretreatment standards for both existing and new sources.
Currently there is only one known direct discharger in the industrial laundry
and linen supply subcategories. A survey 'of NPDES permit applications indicated
that several previously direct dischargers are now discharging to POTWs. Because
of this trend and because it is unlikely that an existing indirect discharger will
become a direct discharger, the Agency has decided not to propose any BPT, BAT,
or BCT limitations. However, since new industrial or linen supply laundry facilities
constructed in the future may be direct dischargers, the Agency is proposing New
Source Performance Standards (NSPS).
9.1 PRETREATMENT STANDARDS FOR EXISTING AND NEW SOURCES
Proposed pretreatment standards are presented in Table 9-1. The
methodology used to develop these standards is presented in the following
subsections.
9.1.1 Technology Basis
The treatment technology used as the basis for developing pretreatment
standards for industrial and linen supply laundries is dissolved air flotation (DAF).
The technology includes flow equalization, chemical addition, and floe removal.
Although only a limited number of laundry facilities currently pretreat their
wastewaters, DAF is the most commonly applied technology in the industry. The
DAF system has shown to be effective in reducing toxic as well as conventional
pollutants.
The Agency investigated other technologies potentially applicable for the
treatment of laundry wastewaters. These technologies, which included
ultrafiltration, electrocoagulation, filtration and carbon adsorption, were rejected
because of limited performance data or for technological reasons. Filtration and
adsorption technologies were rejected primarily because the oil and grease found in
laundry wastes tend to dog or bind such units.
133
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TABLE 9-1. PRETREATMENT STANDARDS NEW AND EXISTING SOURCES
Pollutant
Chromium
Copper
Lead
Zinc
Estimated
Long-Term
Average
mg/1
0.18
0.74
0.93
0.74
Daily
Variability
Factor(l)
4.0
2.7
3.7
4.4
Proposed
Limitations
mg/1
24-hr, max.
0.74
1.5
3.7
2.9
30-day avg.
0.22
0.93
1.7
1.1
(1) Daily variability factor is the ratio of the estimated 99th percentile to the
estimated long term average.
134
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9.1.2 Pollutants to be Regulated
The toxic pollutants selected for pretreatment standards are chromium,
copper, lead, and zinc. These four metals are found most frequently and at the
highest concentrations in both industrial laundry and linen supply wastewaters. A
detailed discussion of the solution and exclusion of specific pollutants is presented in
Section 6 and Appendix A.
The Agency considered regulating major toxic organics but decided not to for
the following reasons. Although DAF effectively removes organics, it is difficult to
quantify that removal because it is often related to the removal of oil and grease.
In addition, technologies that might further remove organics following DAF, and
possibly allow for a numerical limitation were rejected for technological reasons
based on the characteristics of DAF effluent.
9.1.3 Statistical Methodology
Statistical analyses were performed on the laboratory measurements of four
toxic metals; copper, chromium, lead, and zinc found in the treated effluent waste
stream. Statistical calculations for variability factors of daily measurements for
these parameters are included herein, as well as probability performance curves for
30-day averages.
Data Sources - Data used in the development of pretreatment standards for
industrial and linen supply laundries are from the sampling and analysis of
wastewater discharges at eight industrial laundries currently operating DAF
treatment systems. Analytical data are presented in Appendix C. A total of 33
data points (daily samples) were used for statistical analyses; 23 from one laundry
and ten from seven other laundries.
Prestatistical Data Treatment - In recording of actual data, certain data
values were entered as "less than" detectability limits. In these cases, the sample of
monitoring data has been "censored" in the process of data recording since only the
threshold value has been retained (i.e., if a pollutant concentration was reported as
<0.050 mg/1, the value of 0.050 rng/1 was used). In the statistical analysis of
monitoring data, censored data values were included with measured values in the
sample. This practice provides a reasonable approach, both for assessing industry's
capability to perform and environmental concerns for valid pollutant limitations.
Since censoring was done for "less than" bounds, any bias from their inclusion would
cause a slight increase in the long-term average, moderately affecting (in the
direction of leniency toward industry) the estimate of long-term average pollution
levels.
The measurements obtained for each parameter were screened by statistical
methods for spurious or non-representative values. For this test of outliers as well
as other statistical analyses reported herein daily observations of pollutant levels
were assumed to follow the lognormal distribution. Under this assumption the
logarithms of these measurements follow a normal distribution.
The extreme values, i.e., maximum and minimum, were subjected to a
students' t-test for outliers. The test consisted of calculating a t-statistic, given by:
135
-------
t = max ((Ymax -y)/Sy, (y - ymin)/Sy)
where:
Ymax is the logarithm of the datum corresponding to the largest pollutant
measurement, and Ymin is the logarithm of the smallest.
y is the arithmetic mean of the sample logarithms.
Sy is the standard deviation of the sample logarithms.
Where the calculated t-statistic exceeded the 99th percentile of the student's
t distribution appropriate for the particular sample size, that value was rejected as
not belonging to the sample. Whenever an extreme value, either maximum or
minimum was rejected in the test for outliers, the sample statistics were
recomputed with the remaining data, and the screening for outliers performed once
more. The procedure for computing statistics, screening for outliers, rejection of
outliers, if any, and recomputation of statistics continued iteratively until no
outliers were found.
Statistical Analysis - Standard statistical measures of pollution levels in DAF-
treated effluents are tabulated and recorded in Tables 9-2 - 9-4. These include
minimum (Min), arithmetic sample average (Avg), sample maximum (Max),
arithmetic standard deviation (Stdv), and sample coefficient of variation (C.Var).
Table 9-2 presents a statistical summary of data collected at one industrial laundry
over twenty-three days (referred to as Plant Z). The summary does not include data
which was rejected for various reasons (see discussion of outliers above). Table 9-3
presents a statistical summary of data collected from seven different industrial
laundries. At two of the laundries multiple samples were taken so that a total of
ten data points were obtained. This summary also does not include rejected values.
Finally Table 9-4 presents a summary of all data obtained from the industrial
laundries excluding rejected values. Pooling of limited data from several laundries
will give a more comprehensive representation of the average level of pollutant
concentration as well as the variability to be encountered in this industrial
wastewater source.
However, the data from various sources should be consistent before
conclusions are drawn from aggregated or pooled samples.
In order to determine the suitability for combining additional data points with
Plant Z, a statistical test of the hypothesis that data from the seven other laundries
(as a group) came from the same distribution was performed for each of the four
toxic metal pollutants; copper, total chromium, lead, and zinc. The Wilcoxon-Mann-
Whitney test was used with the following results significant at the .02 level:
Cu
Reject
Pooling
Cr(t)
Accept
Pooling
Pb
Reject
Pooling
Zn
Accept
Pooling
In the following paragraphs, the selection of limitations for each of the four
toxic metals is based on the above results. For copper and lead, pooling of the data
136
-------
TABLE 9-2 STATISTICAL SUMMARY OF TREATMENT DATA FOR
PLANT Z
Parameter (mg/1)
Cu
Cr(T)
Pb
Zn
No
19
18
19
19
Min
0.50
0.04
0.04
0.09
Avg
0.86
0.13
0.98
0.77
Max
1.32
0:20
2.48
2.15
Stvd
0.23
0.04
0.73
0.60
C.Var
0.27
0.34
0.74
0.77
137
-------
TABLE 9-3. STATISTICAL SUMMARY OF TREATMENT DATA FOR SEVEN
INDUSTRIAL LAUNDRIES
Parameter (mg/1)
Cu
Cr(T)
Pb
Zn
No
9
8
9
8
Min
0.09
0.03
0.02
0.06
Avg
0.34
0.31
0.13
0.38
Max
0.89
0.62
0.47
1.20
Stdv
0.25
0.22
0.14
0.43
C.Var
0.75
0.72
1.14
1.14
138
-------
TABLE 9-4 STATISTICAL SUMMARY OF TREATMENT DATA FOR ALL
INDUSTRIAL LAUNDRIES
Parameter (mg/1)
Cu
Cr(T)
Pb
Zn
No
28
26
28
27
Min
0.09
0.03
0.02
0.06
Avg
0.69
0.18
0.71
0.66
Max
L32
0.62
2.48
2.15
Std
0.34
0.15
0.72
0.58
C.Var
0.49
0.81
1.03
0.88
139
-------
from all eight laundries is rejected and limitations will be based only on data from
Plant Z. In the case of chromium and zinc, pooling is acceptable and data from all
eight laundries will be used in setting limitations.
Assumptions Concerning Daily Pollutant Level Measurements
In the formulation and calculation of the following performance standards,
individual sample measurements of pollutant levels were assumed to follow the
lognormal distribution, a well known and generally accepted statistical probability
model used in pollution analysis. Under this assumption the logarithms of these
measurements follow a normal probability model. It was also assumed that recorded
measurements can be considered statistically independent and amenable to standard
procedures.
In order to ascertain the suitability of the lognormal distribution for each of
the toxic metals, a 95% confidence band was constructed around the sample
cumulative distribution function, using critical values from the distribution of the
Kolmogorov-Smirnov statistic, Dfvj. Confidence bands are computed as:
C(X) ± DN,
where C(X) is the relative frequency of sample observations less than or equal to a
given pollutant level X.
These confidence bands are plotted on the cumulative distribution plots of
daily measurements in Figures 9-1 through 9-4 inclusive.
In the analysis of daily data, the inherent variability of measured pollutant
levels in the effluent stream from the laundry industry must be incorporated in
calculating upper limits for daily pollutant discharge levels. Even well treated and
controlled plants may experience some days when atypically high level of pollutant
discharge is present in their waste stream. Such variations may be due to a variety
of factors, such as short-term maladjustments in treatment facilities, variation in
flow or pollutant load, or changes in the influent stream. To allow for this
variability, performance standards must necessarily be set above the plant's long-
term average performance and occasional, infrequent excessive discharges
permitted. Since pollutant concentration is often expressed in terms of average
level, it is convenient to describe standards of performance and allow variability in
term of multiples of this average. Such a method of computing limitation standards
as multiples of average level performance is used. The ratio of the pollutant
performance level to the estimated long-term average is commonly called the
"variability factor".
This factor is useful with lognormally distributed pollutant levels because its
value is independent of the long-term average, depending only upon the day-to-day
variability of the process and the expected number of excessive discharge periods.
For a lognormal population, the variability factor (P/A), the performance standard
P, and the long-term average A, are related by:
ln(P/A) = S'(Z - S'/2)
where:
140
-------
POLLUTANT: Copper
Proposed Daily Maximum Limitation (mg/1)
1.5
Long Term Average
Standard Deviation of Daily Measurements
99th percentile (Z=2.33)
Number of Observations
All Data
0.7*
0.3425
1.78
28
Plant "Z"
0.86
0.2334
1.54
19
DO
£
c
o
+3
flj
L*
+•«
w so ,a> n m m a it s»
Percentage
Figure 9-1. Cumulative Distribution of Daily Concentrations from Industrial
Laundry Treated Effluent
141
-------
POLLUTANT: Chromium
Proposed Daily Maximum Limitation (mg/1)
0.74
Long Term Average
Standard Deviation of Daily Measurements
99th percentile (Z=2.33)
Number of Observations
All Data
0.18
0.14
.74
26
Plant "Z"
0.13
0.0438
.26
18
o
'•g
8
§.
u
LOWER CONFIDENCE BAND
30 40 50 611 70 ta 90 95 98 99 99.8 it
nnt fttw 01 nz ns ,t i ? 5 .10
Percentage
Figure 9-2. Cumulative Distribution of Daily Concentrations from Industrial
Laundry Treated Effluent
142
-------
POLLUTANT: Lead
Proposed Daily Maximum Limitation (mg/1)
3.7
All Data
Plant "Z"
Long Term Average
Standard Deviation of Daily Measurements
99th percentile (2=2.33)
Number of Observations
0.93
0.7228
3.54
28
1.15
0.7269
3.68
19
DO
£
o
! Oat 0.1 0.2 0.5 1
Percentage
Figure 9-3. Cumulative Distribution of Daily Concentrations from Industrial
Laundry Treated Effluent
143
-------
POLLUTANT: Zinc
Proposed Daily Maximum Limitation (mg/1)
2.9
All Data
Plant "Z
11711
Long Term Average
Standard Deviation of Daily Measurements
99th percentile (Z=2.33)
Number of Observations
0.74
0.5752
2.90
27
0.87
0.5972
3.01
19
o
ttJ
u
3
LOWER CONFIDENCE BAND
UPPER CONFIDENCE BAND
B.OS 0.1 0.2 OJ 1 I S .10 20 30 40 50 69 70 80 90 95 9S 99 99.8
Percentage
Figure 9-4. Cumulative Distribution of Daily Concentrations from Industrial
Laundry Treated Effluent
144
-------
1. "In" represent the natural logarithm (base e) of a numerical quantity.
2. 5' is the estimated standard deviation of the logarithms of pollutant level
measurements.
3. Z is a factor derived from the standard normal distribution. Z is chosen
as Z = 2.33 so as to give performance limitations which provide a balance
between appropriate consideration of day to day variation in a properly
operating plant and the necessity to insure that a plant is functioning
properly.
This Z-value corresponds to the 99th percentile of the lognormal distribution
meaning that only 1 percent of the pollutant observations taken from a plant with
proper operation of treatment facilities would be greater than the performance
standard, P. This percentile is equivalent to allowing a plant in normal operation 3
to 4 exceedances per year.
Calculation of Variability Factors
As mentioned above, statistical analysis of daily pollution level measurements
was based on the assumption that these data, (XI, X2,...Xn), follow a lognormal
distribution. Following this assumption, if Yi=ln(Xi), where ln(Xi) represents the
natural logarithm or log base e of the pollution measurements,then the Yi; i=l,2,...n
are each normally distributed. If A' and S1 are the mean and standard deviation of
Y=ln(X) respectively, then the probability of k percent that an individual Y will not
exceed A'+ZS', where Z is the k-th percentile of the standard normal distribution,
e.g. Z=2.33, is the 99-th percentile of the standard normal distribution. It follows
that A'+ZS1 is the natural logarithm of the k-th percentile of X and that the
probability is k percent that X will not exceed a performance standard P=
exp(A'+ZS'). It is also known that the average value of X is A= exp(Al+S'(5'/2)). The
variability factor VF, is obtained by dividing P by A, hence,
VF = P/A = exp(S'(Z - S'/2)), and
ln(VF) = ln(P/A) = S'(Z - S'/2)
To estimate the VF for a particular set of monitoring data, S' may be
calculated as the square root of ln(1.0 + (CV)2), where the sample coefficient of
variation, CV = S/X, is the ratio of sample standard deviation to sample average.
Example Calculation of Variability Factors for 24-Hour Data
Given the following descriptive statistics for a particular parameter, as might
be found for copper (mg/1) in Table 9-3.
No.
1 28
Min
Avg
0.69
Stdv
0.09 0.69 1.32 0.3*
Calculate the estimated standard deviation of logarithms
(S1)2 = In (1.0 + 0.492) = 0.219
CV
0.49
145
-------
S1 = 0.468
Then
ln(P/A) = 0.468(2.33 - 0.468/2) = 0.981
The variability Factor VF is,
VF = P/A = exp (0.981) = 2.67
The performance standard P;
P = A(VF) = A(P/A) = (0.69X2.67) = 1.84 mg/1
The statistical interpretation of P, the performance standard, is that one
estimates that 99 percent of the daily pollution level measurements will not exceed
P. For large data sets, P is roughly equivalent to an upper 99 percent confidence
bound for an individual daily measurement.
Graphs of the cumulative distribution of sample results for each of these four
toxic metals being regulated are given in Figures 9-1 through 9-4. These graphs plot
cumulative relative frequency in the sample vs logarithm of pollutant concentration,
and are so scaled that a lognormally distributed variable plots as a straight line.
ASSUMPTIONS CONCERNING 30-DAY AVERAGE POLLUTANT LEVEL
MEASUREMENTS
Although individual pollution concentration measurements are assumed
lognormally distributed, that distribution does not extend to the statistical behavior
of averages, in this case where 30-day averages are to be used. However, if
averages are taken* over a "reasonably large" number of days, a statistical principle,
the Central Limit theorem, assures that probabilities pertaining to such averages
may be computed using the normal probability distribution. A 30-day average
contains enough individual daily measurements to insure that the normal probability
performance, even when daily values are lognormally distributed.
To assess the treatability level for the industrial laundry treatment technology
of DAF, the "probability performance" was calculated for each parameter in the
treated effluent stream. This quantity is the probability that a given stream will
have a 30-day average pollutant level (mg/1) that is within or less than a given level.
This amounts to the probability that a plant employing the proposed treatment will
produce a 30-day average concentration less than the corresponding level. Where a
pollutant discharge level is measured by the average concentration in thirty
individual daily measurements (the 30-day average), the probability performance is
the estimate of the proportion or fraction of the 30-day averages that will be less
than or equal to the given pollutant concentration.
146
-------
COMPUTATIONAL PROCEDURES FOR ESTIMATES OF 30-DAY AVERAGE
PERFORMANCE
To compute the maximum likelihood estimates (MLE's) of probability
performance, it is necessary to compute the MLE's of the long-term average
pollution level and the long-term standard deviation of pollution level using
logarithms of the individual measurements of data. The maximum likelihood
estimates of the mean logarithm and standard deviation of logarithms are done using
standard statistical formulae.
These estimates are computed and used to obtain the MLE's of the long-term
average, A, and long-term standard deviation, S, of the pollutant concentration.
Dividing the estimated long-term standard deviation, 5, by the square root of the
number of days (30) in the average, gives S*. the estimated standard error of the 30-
day average, and which can be used in computing probability performance. For any
pollutant level, P, the estimated probability performance, is computed as:
Probability (30-day average does not exceed P) = Pr(z)
where z = (P-A)/S*
and Pr(z) = probability that a standardized normal value does not exceed z.
Included with the technical analysis of each toxic metal are the probability
performance curves, Figures 9-5 through 9-8 and estimates of long-term averages
for each parameter. Note that the estimate of long-term pollution average is
obtained by maximum likelihood methods from the lognormal distribution and does
not necessarily equal the sample arithmetic average given in Tables 9-2 to 9-4.
Where a parameter curve is quite "steep", i.e., for those parameters that show
a sharp increase in probability (of a 30-day average not exceeding a given value) for
a small increase in pollution concentration, this is primarily due to a relatively small
coefficient of variation. In other words, the steepness of the curve is directly
related to the degree of consistency in the sample results.
9.2 NEW SOURCE PERFORMANCE STANDARDS
Proposed new source performance
laundries are presented in Table 9-2.
9.2.1 technology Basis
standards for industrial and linen supply
For NSPS, the Agency proposes the same treatment technology that is
proposed for pretreatrnent standards, dissolved air flotation, but with the addition of
biological treatment for the further reduction of conventional pollutants. Trickling
filters or stablization ponds (facultative lagoons) are recommended as biological
treatment options.
9.2.2 Pollutants to be Regulated
The toxic pollutants selected for NSPS are the same as those selected for
pretreatment standards, chromium, copper, lead, and zinc. The conventional
147
-------
POLLUTANT: Copper
Proposed Maximum 30-Day Average (mg/1)
0.93
Estimated Long Term Average
Standard Error of the 30-Day Average
95th percentile (Z=1.64)
Number of Observations
All Data
0.7*
0.1095
0.92
28
Plant "Z"
0
19
0.86
0.0*2
93
roblity Any 30-Day
s Not Exceed a Given Concentration
hat
ab
•o
-------
POLLUTANT: Chromium
Proposed Maximum 30-Day Average (mg/1)
0.22
Estimated Long Term Average
Standard Error of the 30-Day Average
95th percentile (Z= 1.6*)
Number of Observations
All Data
0.18
0.0253
0.22
26
Plant "Z"
0
0
0
18
13
0096
15
o
.«H
-M
2
•i->
^ «
l1^
9cS
o w
(0 O
•§Z
to
V
DATA
'
^
x^
k
^--
0.12 0.14
0.16
0.18
0.2Q
0.22
Concentration (mg/1)
Figure 9-6. Estimated Performance of Proposed DAF Treatment
149
-------
POLLUTANT: Lead
Proposed Maximum 30-Day Average (mg/1)
1.7
Estimated Long Term Average
Standard Error of the 30-Day Average
95th percentile (Z=1.64)
Number of Observations
All Data
0.93
0.4615
1.69
28
Plant "Z"
1.15
0.3121
1.66
19
f 30-Day
en Concentration
) O O O H
• • • •
* ^J 00 VO O
c.2 u.t>
> CJ
t! x n 4
:r! uj U.fi
IS +j
« o
o "" 0.3
V- 03
o<
-------
POLLUTANT: Zinc
Proposed Maximum 30-Day Average (mg/1)
1.1
Estimated Long Term Average
Standard Error of the 30-Day Average
95th percentile (Z=1.6*)
Number of Observations
All Data
0.7*
0.2113
1.09
27
Plant "Z"
0.87
0.21*2
1.22
19
1.0
c
o _ A
•2 0.9
td
L,
+••
^ % 0.8
>> u
<3'c
9fl
o u 0.7
CO C
•*. <"
c\S
<0 0.6
13 "*
ni o.s
>% u
•- iS
5" 0.4
m o
•§Z
i- to no
a, (U ,
n3^ 0.1
0.0
ALL DATA
^
7*
^*^
/
/
Xt
0
/
/
/
\
.5
rl
/
/
/
/
\
i
/
••!/
•
i
/
/
-j!
/ i
y
/
/
/
/
i.
/
K.
/
/
1
x
11 !
,x-r
^
- PLANT
x^j
Z
Y~*
0 I
.5 ' 2.
.
0 2
.5
Concentration (mg/1)
Figure 9-8. Estimated Performance of Proposed DAF Treatment
15-1
-------
pollutants selected for regulation are TSS, BOD, and oil and grease, the major
classical pollutants found in laundry wastes.
9.2.3 Basis for Numerical Limitations
Toxic metals limitations are the same as those proposed for pretreatment
standards. The basis for the limitations is presented in Section 9.1.
Because only one direct discharger has been identified in the linen supply and
industrial laundry subcategories, the Agency is proposing NSPS limitations for
conventional pollutants, TSS, BOD, and oil and grease, equal to those currently
imposed on that direct discharger. The Agency has determined that the limitations
are achievable using the technologies of DAF and biological treatment.
152
-------
REFERENCES
1. Draft Preliminary Qualitative Economic Assessment of Effluent Limitations in
the Laundries Industry. Contract 68-01-4618, U.S. Environmental Protection
Agency, Washington, D.C. (Preliminary document submitted to EPA by Energy
and Environmental Analysis, Inc., September 8, 1977.) 25 pp.
2. Economic Effects of Water Pollution Control on the Laundry Industry, Phase
II. Contract 68-01-2412, U.S. Environmental Protection Agency, Washington,
D.C. (Preliminary document submitted to EPA by Colin A. Houston &
Associates, Inc., April 15, 1974.) 207 pp.
3. Preliminary Quantitative Economic Assessment of Effluent Limitations in the
Laundries Industry. Contract 68-01-4618, U.S. Environmental Protection
Agency, Washington, D.C. (Preliminary document submitted to EPA by Energy
and Environmental Analysis, Inc., January 10, 1978.) 72 pp.
4. Johnson, K.C. Laundering. Ins Kirk-Othmer Encyclopedia of Chemical
Technology, Second Edition, Vol. 12. John Wiley & Sons, Inc., New York, New
York, 1967. pp. 197-207.
5. Osos, G. R. Successful Steam Tunnel Finishing. Linen Supply News, 61(2):90-
92, 1977.
6. Wile, J. L. Latest Development Rundown on Washroom Machinery & Supplies.
Institutional Laundry, 16(8):20-22, 1972.
7. Martin, A. R., F. Loibl, G. E. Leonhardt, and H. E. Reeves. Drycleaning. In?
Kirk-Othmer Encyclopedia of Chemical Technology, Second Edition, Vol. 7.
John Wiley & Sons, Inc., New York, New York, 1965. pp. 307-326.
8. Development Document for Effluent Limitations Guidelines and New Source
Performance Standards for the Auto and Other Laundries Category, Part I.
U.S. Environmental Protection Agency, Washington, D.C. (EPA draft
document, January 1977.)
9. Powder Power Puts Profit in Solvent Recovery. Laundry Cleaning World,
1(2):18-19, 1973.
10. Bee, B. Increasing Solvent Mileage. Coinamatic Age, 34(4):38, 1976.
11. McCoy, J.R. Solvent Filtration with Cartridge Type Filters. Coinamatic Age,
34(4):28-30, 1976. -
153
-------
12.
13.
REFERENCES - continued
Hasenclever, K.D. The Basis of Effective Drycleaning Distillation.
Laundry & Cleaning News, pp. 15-17, June 1977.
Power
An "update" on workwear processing in the USA.
News, November 11, 1977.
Power Laundry and Cleaning
14. Kleper, M. H., R. L. Goldsmith, and A. Z. Gollen. Demonstration of
Ultrafiltration and Carbon Adsorption for Treatment of Industrial Laundering
Wastewater. EPA-600/2-78-177, U.S. Environmental Protection Agency,
Cincinnati, Ohio, August 1978. 121 pp.
15. Rosenthal, B. L. et al. Industrial Laundry Waste Water Treatment Study.
Project #48, Massachusetts Health Research Institute, Inc., Boston,
Massachusetts, April 1964. 93 pp.
16. Cogely, D. R. and B. A. Weschler. Occurrence and Treatability of Priority
Pollutants in Industrial Laundry Wastewaters. Draft Final Report. Grant No.
S-804367-01, U.S. Environmental Protection Agency, Cincinnati, Ohio.
January 1978. 110pp.
17. Douglas, G. Modular Wastewater Treatment System Demonstration for the
Textile Maintenance Industry. EPA-660/2-73-037, U.S. Environmental
Protection Agency, Washington, D.C., January 1974. 342 pp.
18. Van Hess, W., E. W. Lard, and Dr. R. McMinn. A Continuous Shipboard
Laundry Wastewater Treatment and Recycling System. David W. Taylor Naval
Ship Research and Development Center, Annapolis, Maryland. 19 pp.
19. Guarino, V. J., and R. A. Bambenek. Development and Testing of a
Wastewater Recycler and Heater. EPA-600/2-76-289. U.S. Environmental
Protection Agency, Cincinnati, Ohio. December 1976. 106 pp.
20. Lent, D. S. Treatment of Power Laundry Wastewater Utilizing Powdered
Activated Carbon and Cationic Polyelectrolytes. In: Proceedings of the 30th
Industrial Waste Conference, Purdue University, Lafayette, Indiana, May 1975.
Ann Arbor Science Publishers, Inc., Ann Arbor, Michigan. January 1976.
21. Galonion, G. E., and D. B. Aulenback. Phosphate Removal from Laundry
Wastewater. Journal of the Water Pollution Control Federation, 45(8):1708-
1717. August 1973.
22. Aulenback, D. D., P. C. Town, and M. Chilson. Treatment of Laundromat
Wastes. EPA-R2-73-108, U.S. Environmental Protection Agency, Washington,
D.C., February 1973. 65 pp.
23. Wastewater Engineering, Collection, Treatment, and Disposal. Metcalf and
Eddy, Inc., McGraw-Hill Book Company, New York, New York, 1972. 782 pp.
154
-------
24.
REFERENCES - continued
Patterson, I. W. Wastewater Treatment Technology. Ann Arbor Science
Publishers, Inc., Ann Arbor, Michigan, 1975. pp 175-189.
25. Process Design Manual for Upgrading Existing Wastewater Treatment Plants.
Technology Transfer, U.S. Environmental Protection Agency, Cincinnati, Ohio,
October 197*.
26. O'Melia, C.R. Coagulation and Flocculation. In; Physicochemical Processes
for Water Quality Control, Chapter 2, W. 3. Webster, 3r., ed. Wiley-
Interscience, New York, New York, 1972. pp. 61-91.
27. Process Design Manual for Suspended Solids Removal - Technology Transfer,
U.S. Environmental Protection Agency, Cincinnati, Ohio, January 1975. pp. 4-
1, 4-2.
28. Wastewater Treatment Plant Design, Manual of Practice No. 8.
Pollution Control Federation, Washington, D.C., 1977. 560 pp.
Water
29. Pinto, S.D., Uitrafiltratioh for Dewatering of Waste Emulsified Oil's, In:
Proceedings, First International Conference, Lubrication Challenges in
Metal working and Processing, IIT Research Institute, Chicago, Illinois, 1978. 4
PP-
30. Ramirez, E. R. Electrocoagulation Clarified Food Wastewater. Deeds and
Data, Water Pollution Control Federation, April 1975. 3 pp.
31. Minturn, R. E., 3. S. Johnson, 3r., W. M. Schofield, and D. K. Todd.
Hyperfiltration of Laundry Wastes. Water Research, 8(11):921-926, 1974.
32. Grives, R. B., and 3. L. Bewley. Treating Laundry Wastes by Foam Separation.
3ournal of the Water Pollution Control Federation, 45(3):470-479, 1973.
33. McCarthy, 3. 3., and R. H. Chyvek. Evaluation of a Vapor Compression
Distillation Unit for Laundry Wastewater Reuse. Technical Report 7711, U.S.
Army Medical Research and Development Command, Washington, D.C.,
August 1977. 45 pp.
34. Baker, R. 3. Degan, and R. Weston. Pilot Plant Studies of the Biological
Treatment of Petroleum Refinery Wastes. Ini Proceedings of the
Pennsylvania Sewage Wastes Association, August 1952.
35. Coe, R. Bench-Scale Biological Oxidation of Refinery Wastes with Activated
Sludge. Sewage Industrial Wastes, 24(6):1952.
36. Tabakin, R. B., R. Trattner, and P. N. Chevemisinoff. Oil/Water Separation
Technology: The Option Available, Part 2. Water and Sewage Works,
125(8):72-75, 1978.
155
-------
REFERENCES - continued
37. Process Design Manual for Sludge Treatment and Disposal. Technology
Transfer, U.S. Environmental Protection Agency, Cincinnati, Ohio, October
1974. pp. 7-1/7-94.
38. Federal Register. 43(243):58956-58957, December 18, 1978.
39. Meredith, D. C., K. W. Wong, R. W. Woodhead, and R. H. Wortman. Design
and Planning of Engineering Systems. Prentice-Hall, Inc., Englewood Cliffs,
New Jersey, 1973. 393 pp.
40. Current Prices of Chemicals and Related Materials. Chemical Marketing
Reporter, 215(3):40-49.
41. Parker, R. S., Jr. Assessment of Dissolved Air Flotation Sludge Management
Options in Industrial Laundry Wastewater Treatment. (Draft) Contract No. S-
804367-01. U.S. Environmental Protection Agency, Cincinnati, Ohio, October
1978. 48pp.
42. Van Note, R. H., P. V. Hebert, R. M. Patel, C. Chupek, and L. Feldman. A
Guide of the Selection of Cost-Effective Wastewater Treatment Systems.
EPA-430/9-75-002, U.S. Environmental Protection Agency, Washington, D.C.,
July 1975.
43. Peters, M.S. and K. D. Timmerhaus. Plant Design and Economics for
Chemical Engineers. McGraw-Hill Book Company, New York, New York,
1968, 850 pp.
44. Pound, C. E., R. W. Cites, and D. A. Griffes. Cost of Wastewater Treatment
by Land Application. EPA-430/9-75-003, U.S. Environmental Protection
Agency, Washington, D.C., June 1975. 156 pp.
45. Letter from Institute of Industrial Launderers to Environmental Protection
Agency; October 31, 1979.
46. Nemerow, N. L. Liquid Waste of Industry, Theories, Practices, and Treatment.
Addison-Westey Publishing Company, Reading, Massachusetts, 1971. 584 pp.
47. Federal Guidelines, State and Local Pretreatment Programs. Volume 1.
EPA-430/9-76-017a, U.S. Environmental Protection Agency, Washington,
D.C., January 1977. '196 pp.
48. Beychok, M. R., Aqueous Wastes from Petroleum and Petrochemical Plants,
John Wiley & Sons, N.Y., 1967.
49. NIH-EPA Chemical Information System, The Oil and Hazardous Materials -
Technical Assistance Data System (OHMTADS), May 21, 1979.
156
-------
REFERENCES - continued
50. "Anaerobic Processes - Literature Review", Ghosh, 5., Journal of the Water
Poilution Control Federation, Vol. 44, No. 6, June 1972. p. 948.
51. "Inhibition of Anaerobic Digestion of Sewage Sludge by Chlorinated
Hydrocarbons," Swanwick, J. D. and Margaret Foulkes, Water Pollution
Control, Vol. 70, 1971. p. 58.
52. "The Effect of Chloroform in Sewage on the Production of Gas from
Laboratory Digesters," Stickley, D. P., Water Pollution Control, Vol. 69, 1970.
p. 585.
53. "Combined Treatment of Chemical Wastes and Domestic Sewage in Germany",
Bischofsberger, Wolfgang, Proceedings of the 24th Industrial Waste
Conference (1969), Purdue University, p. 920.
54. Ryer, F. V. Soap. In: Kirk-Othmer Encyclopedia of Chemical Technology,
Second Edition, Vol. 18. John Wiley & Sons, Inc., New York, New York, 1969.
pp. 415-432.
55. Schwartz, A. M. Detergency. In: Kirk-Othmer Encyclopedia of Chemical
Technology, Second Edition, Vol. 6. John Wiley & Sons, Inc., New York, New
York, 1965. pp. 853-895.
56. Zweidler, R., H. Hausermann, and J. R. Geigy. Brighteners, Optical. In:
Kirk-Othmer Encyclopedia of Chemical Technology, Second Edition, Vol. 3.
John Wiley & Sons, Inc., New York, New York, 1964. pp. 737-750.
57. Current Prices of Chemicals and Related Materials. Chemical Marketing
Reporter, 215(3):40-49.
58. Parker, R. S., Jr. Assessment of Dissolved Air Flotation Sludge Management
Options in Industrial Laundry Wastewater Treatment. (Draft) Contract No.
S-804367-01. U.S. Environmental Protection Agency, Cincinnati, Ohio,
October 1978. 48 pp.
59. Van Note, R. H., P. V. Hebert, R. M. Patel, C. Chupek, and L. Feldman. A
Guide to the Selection of Cost-Effective Wastewater Treatment Systems.
EPA-430/9-75-002, U.S. Environmental Protection Agency, Washington, D.C.,
July 1975.
60. Peters, M. S. and K. D. Timmerhaus. Plant Design and Economics for
Chemical Engineers. McGraw-Hill Book Company, New York, New York,
1968. 850pp.
61. Pound, C. E., R. W. Cites, and D. A. Griffes. Costs of Wastewater Treatment
by Land Application. EPA-430/9-75-003, U.S. Environmental Protection
Agency, Washington, D.C., June 1975. 156 pp.
62. Meredith, D. C., K.:W. Wong, R. W. Woodhead, and R. H. Wortman. Design
and Planning of Engineering Systems. Prentice-Hall, Inc., Englewood Cliffs,
New Jersey, 1973. 393 pp.
157
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APPENDIX A
BASIS FOR EXCLUSION OF TOXIC POLLUTANTS
Authority—The primary authority for excluding specific toxic pollutants is
provided by Paragraph 8 of the Settlement Agreement in Natural Resources Defense
Council, Inc. v. Train, 8 ERG 2120 (D.D.C. 1976), as modified, Natural Resources
Def^nsejguncil, Inc. v. Costle, 12 ERG 1833 (DoD.C. 1979). For the Linen Supply
and Industrial Laundry Subcategoriesy Paragraph 8(a)(iii) contains the major bases
for excluding specific toxic pollutants.
Where Paragraph 8 exclusions do not apply to a given nonregulated toxic
pollutant, that pollutant is deferred.
Bases for Exclusion—-Eighty-three toxic pollutants are excluded for all
subcategories under Paragraph 8(a)(iii) because they were not detectable in the
sampled linen supply and industrial laundry waste waters using approved analytical
methods. These pollutants are listed in Table 1 of this notice.
Table 2 presents the toxic pollutants that were detected during sampling but
have been excluded from regulation. The column headings in Table 2 assign a letter
to each basis for exclusion. Each letter corresponds to the detailed descriptions of
the various bases which follow:
V .
Basis A - Under Paragraph 8(a)(iii), the Administrator may exclude from
regulation any toxic pollutant which is "present only in trace amounts and is neither
causing nor likely to cause toxic effects". Where a specific toxic pollutant showed
an average influent pollutant concentration of <5Q ug/1 over the entire sample
population, it was presumed that the above provision would be applicable to permit
exclusion of that pollutant.
Basis B - Under Paragraph 8(a)(iii), the Administrator may exclude from
regulation any pollutant "present in amounts too small to be effectively reduced by
technologies 'known to the Administrator." As explained in Section 7 of this
document, dissolved air flotation (DAF) is the recommended level of technology for
discharge limitations within the linen supply and industrial laundry subcategories.
The above provision was presumed applicable where treatability data for a given
toxic pollutant (Table 2) indicated that technology was ineffective in removing that
pollutant where its influent concentration was low.
Basis C - Under Paragraph 8(a)(iii), the Administrator may exclude from
regulation any toxic pollutant which "will be effectively controlled by the
technologies upon which are based other effluent limitations and guidelines,
standards of performance, or pretreatment standards." This provision was presumed
A-l
-------
applicable where treatability data indicated that DAF technology reduced a given
pollutant to an acceptable level. As explained above, dissolved air flotation is the
recommended level of treatment for meeting discharge limitations in the linen
supply and industrial laundry subcategories.
A-2
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TABLE 1
EXCLUDED TOXIC POLLUTANTS NOT DETECTED DURING ANALYSIS
TOXIC'POLLUTANT
1. *Acenaphthene
2. *Acrolein
3. *Acrylonitrile
5. *Benzidine
7. *Chlorobenzene
8. if2f4-Trichlorobenzene
9. Hexachlorobenzene
10» l,2~Diehloro@than@
12. Hexaehloroethane
13. 1,1-Dichloroethane
14. 1,1,2-Triehloroethane
15. 1,1?2f2-Tetrachloroethane
16. Chloroethane
17. Bis(chloromethyl) ether
18. Bis(2~chloroethyl) ether
19. 2-Chloroethyl vinyl ether (mixed)
21. 2,4,6-Trichlorophenol
24. *2-Chlorophenol
28. 3,3'-Dichlorobenzidine
29. 1,1-Dichloroethylene
30. 1,2-Trans-dichloroethylene
32. 1,2-Dichloropropane
33e 1,2-Dichloropropylene (1,3-dichloropropene)
35. 2,4-Dinitrotoluene
36. 2,6-Dinitrotoluene
37. *l,2-=Diphenylhydrazine
39. *Fluoranthene
40. 4-Chlorophenyl phenyl ether
41= 4-=Bromophenyl phenyl ether
42. Bis(2-ehloroisopropyl) ether
43. Bis(2-chloroethoxy) methane
45. Methyl chloride (chloromethane)
46. Methyl bromide (brpmomethane)
47. Bromofbrm (tribromomethane)
48. Dichlorobromomethane
50. Dichlorodifluoromethane
52. *Hexachlorobutadiene
53. *Hexachlorocyclopentadiene
56. *Nitrobenzene
57. 2-Nitrophenol
58. 4-Nitrophenol
59. 2,4-Dinitrophenol
(continued)
A-3
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TABLE 1 - continued
TOXIC POLLUTANT
60. 4,6-Dinitro-o-cresol
61. N-nitrosodimethylamine
63. N-nitrosodi-n-propylamine
64. *Pentachlorophenol
72. Benzo(a)anthracene (1,2-benzanthracene)
73. Benzo (a) pyrene (3,4-benzopyrene)
74. 3,4-Benzofluoranthene
75. Benzo (k) fluoranthane (11,12-benzo£luoranthene)
76. Chrysene
77. -Acenaphthylene
79. Benzo(ghi)perylene (1,12-benzoperylene)
80. Fluorene
82. Dibenzo (afh)anthracene (1,2,5,6-dibenzanthracene)
83. Indeno (l,2,3-cd)pyrene (2,3,-0-phenylenepyrene)
84. Pyrene
88. *Vinyl chloride (chloroethylene)
89. *Aldrin
90. *Dieldrin
91. *Chlordane (technical mixture & metabolites)
92. 4,4'-DDT
93. 4,4'-DDE (p,p'-DDX)
94. 4,4'DDD (p,p'-TDE)
95. A-endosulfan-Alpha
96. B-endosulfan-Beta
97. Endosulfan sulfate
98. Endrin
99. Endrin aldehyde
100. Heptachlor
101. Heptachlor epoxide
102. ,A-BHC-Alpha
103. B-BHC-Beta
104. R-BHC (lindane)-Gamma
105. G-BHC-Delta
106. PCB-1242 (Arochlor 1242)
107. PCB-1254 (Arochlor 1254)
108. PCB-1221 (Arcohlor 1221)
109. PCB-1232 (Arochlor 1232)
110. PCB-1248 (Arochlor 1248)
111. PCB-1260 (Arochlor 1260)
112. PCB-1016 (Arochlor 1016)
113. *Toxaphene
127. *Thallium (total)
*Specific compounds and chemical classes as listed in the
Consent Decree.
A-4
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TABLE 2
EXCLUDED TOXIC POLLUTANTS DETECTED IN WASTEWATERS
Toxic Pollutant
Basis for
Exclusion**
ABC
4. Benzene
6. Carbon tetrachloride (tetrachloromethane)
11. 1,1,1-Trichloroethane
20. 2-Chloronaphthalene
22. Para-chloro-meta-cresol
23. *Chloroform (trichloromethane)
25. 1,2-Dichlorobenzene
26. 1,3-Dichlorobenzene
27. 1,4-Dichlorobenzene
31. *2,4-Dichlorophenol
34. *2,4-Dimethylphenol
38. *Ethylbenzene
44. Methylene chloride (dichloromethane)
49. Trichlorofluoromethane
51. chlorodibromomethane
54. *Isophorone
55. *Naphthalene
62. N-nitrosodiphenylamine
65. *Phenol
66. Bis(2-ethylhexyl) phthalate
67. Butyl benzyl phthalate
68. Di-n-butyl phthalate
69. Di-n-octyl phthalate
70. Diethyl phthalate
71. Dimethyl phthalate
78. Anthracene
81. Phenanthrene
85. *Tetrachloroethylene
86. *Toluene
87. *Trichloroethylene
114. *Antimony (Total)
115. *Arsenic (Total)
117. Beryllium (Total)
118. *Cadmium (Total)
121. *Cyanide (Total)
123. *Mercury (Total)
124. *Nickel (Total)
125. *Selenium (Total)
126. Silver (Total)
* Specific compounds and chemical classes as
Consent Decree.
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
listed
** See Section IX (A) of this notice for explanation
exclusion designations.
X
X
X
X
X
X
X
X
•
X
X
x
in the
of lettered
A-5
-------
-------
APPENDIX B
SURVEY OF THE AVAILABILITY OF SPACE
FOR WASTE WATER TREATMENT
AT INDUSTRIAL LAUNDRIES
Prepared for
Effluent Guidelines Division
Office of Water and Hazardous Materials
UoS. Environmental Protection Agency
Washington, B.C. 20460
November 1979
-------
INTRODUCTION
A study to determine the availability of space for the
installation of equipment for treatment of industrial laundering
waste water was conducted by the Jacobs Environmental Division of
Jacobs Engineering Group, Inc. under EPA Mission Contract No.
68-01-5767. The study consisted of a survey of 45 randomly
selected sites located in major metropolitan areas of the United
States. The sites were visited to gather information on plant
size, plant operations and waste water volumes and to assess the
availability of space for waste water treatment. Where space was
not readily available, an estimate of the cost of preparing space
or acquiring new space was made.
1,0 PURPOSE
• The purpose of this study was to provide an estimate of the
percentage of industrial l.aunderers with available space,
interior or exterior, for the installation of treatment systems
and to provide a breakdown of costs expected to be incurred by
facilities lacking readily available space.
A worst-case cost estimate, previously prepared, indicated
that costs for treatment of laundry wastes could be prohibitive
if space for equipment was not available. Since input from
industry sources indicated that space was generally not
available, it was evident that a site survey of the industry was
necessary.
2.0 SURVEY APPROACH
2.1 Target Population: Linen Supply and Industrial Launderers
The original design of the survey was to encompass sampling
from Industrial Launderers (SIC 7218) and Linen Supply (SIC
7213). In order.to ascertain the composition and extent of these
two segments of the laundry industry, reference was made to two
sources; e.g.. County Business Patterns and the EPA Draft
Development Document for Autos and Other Laundries. Table 2-1
presents the total number of U.S. establishments from these
B-l
-------
TABLE 2-1. REFERENCED NUMBER OP ESTABLISHMENTS IN U.S.
INDUSTRIAL LAUNDERERS (SIC 7218)
LINEN SUPPLY (SIC 7213)
Primary SIC
7213 7218
1167
1300
913
1000
Reference
County Business Patterns, 1976
EPA Dra-ft Development Document,
1978
B-2
-------
sources.
It was recognized during the initial planning of the survey
that the most severe economic impact due to lack of space for
treatment systems would more likely occur in metropolitan or
land-congested areas. Therefore, a decision was made to initiate
the survey in concentrated metropolitan centers. It was also
felt that industrial launderers and linen suppliers would be
found to be located near these centers approximately to the
degree that population is concentrated.
The Standard Metropolitan Statistical Area (SMSA) was chosen
as the geographic unit on which to base the sample design. It
has been estimated that at least 75 percent of the U.S.
population is located within SMSAs. For a given metropolitan
area, an SMSA may include a more representative cross section
than units having political boundaries such as cities or
counties. '
Since a major component of survey costs for this study was
travel to the SMSA rather than travel within a metropolitan area,
the five largest SMSAs which include the cities of New York, Los
Angeles, Philadelphia, Chicago, and Detroit were chosen for
survey. This provided sampling of laundries in areas of heaviest
population concentration while covering the largest fraction of
the laundry industry for a given number of trips.
Since it was necessary to formulate a survey design and plan
which would encompass all industrial .launderers and linen supply
including those not having SIC 7218 or 7213 as primary
classifications, the sampling frame was based on information from
two sources: telephone directory yellow pages and Dun and
Bradstreet Market Identifiers data base. Both sources were
required because little overlap was found to exist between the
two sources. Table 2-2 shows the state of knowledge concerning
establishments in these two industries.
It can be seen from the above table that one industrial
laundry or linen supply in seven (14.2%) is located in one of the
five .largest SMSAs »
2.2 Target Populations Industrial .Laundries
During the course of the study, emphasis was directed toward
industrial laundering as the target population since this
industry generates larger pollutant loads and is more likely to
be regulated. Since many linen supply establishments also have
industrial laundering as a secondary or other SIC operation,
however, linen supplies were not excluded from the list of
potential survey sites.
B-3
-------
TABLE 2-2.
NUMBER OF ESTABLISHMENTS* IN FIVE LARGEST STANDARD
METROPOLITAN STATISTICAL AREAS
INDUSTRIAL LAUNDERERS (SIC 7218)
LINEN SUPPLY (SIC 7213}
Standard
Metropolitan1 Duns
Statistical
Area Id
New York
Los Angeles
Philadelphia
Chicago
Detroit
Subtotal
Remainder of U.S.
In SMS A -
Outside SMSA
National Total
t Brad street
Market
lentifiers
118
75
45
60
53
351
1414
705
2470
Telephone Both D&B Net
Directory and Composite
Yellow Yellow Sampling
Pages Pages Frame
11.7 72 163
88 26 137
79 22 102
69 29 100
64 . 27 90
417 176 592
. '
* Establishments which declare SIC 7218 or SIC 7213 as primary
. through sixth Standard Industrial Classification to D&B
Marketing Services.
•B-4
-------
Because the target population consisted of both telephone
directory listings and Dun & Bradstreet data with little overlap,
and since there was no way to classify telephone listings,
estimates of the number of industrial laundry establishments were
made by using the fraction previously indicated for Dun &
Bradstreet. Table 2-3 shows these estimates.
It can be seen that from this estimate approximately 18
percent of all U.S. industrial launderers occur in one of the
five largest SMSAs.
2.3 Site Selection
To assure that all industrial laundering facilities were
included in the target population for potential site surveys, the
total known list of facilities in both SIC 7213 and SIC 7218 in
the five SMSAs was used for the sampling frame. Facilities were
numbered, and, from a list of random numbers, .were assigned an
order from which to be chosen to be surveyed.
Through telephone contacts, sites were either scheduled for
survey visits or eliminated from the survey. When requested,
Section 308 letters were sent to scheduled sites. The following
criteria were used for scheduling sites:
"7T'"5
a) Must not be a small operator; must have
at least ten employees.
b) Must have industrial laundering as at least
ten percent of plant operation.
Table °2-4 shows the number of sites contacted and scheduled
for survey. Los Angeles sites were randomly selected and
contacted from telephone directory listings before Dun and
• Bradstreet listings were available.
2.4 Site Survey
.•
For consistency, a survey form was developed for use by the
field survey personnel. The form includes information regarding
plant production, waste water generation existing treatment and
space available for treatment units. A copy of the form is
attached. In addition to completing the forms, survey personnel
prepared diagrams indicating potential locations for treatment
.systems.
The treatment system for which space requirements were
B-5
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TABLE 2-3, NUMBER OF INDUSTRIAL LAUNDERERS* IN FIVE
LARGEST SMSAs. (SIC 7218)
Standard
Metropolitan
Statistical
Dun & Bradstreet
Market
Identifiers
Net
Composite
Sam pi ing
Estimated
Industry
Total Number
«i <=d
New York
Los Angeles
Philadelphia
Chicago
Detroit
SIC 7218
and
SIC 7213
118
75
45
60
53
SIC 7218
only
35
27
15
29
26
ti k W&ttVS
163
137
102
100
90
(SIC 7218
48
49
34
48
44
^A>4Uft^&A *•
only)
Subtotal 351
Remainder of U.S.
In SMSA 1414
Outside SMSA 705
132
419
185
592
223
708
312
National Total 2470
736
1243
Jl
* Establishments which have SI 7218 as primary through si^th
Standard Industrial Classification.
B-6
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TABLE 2-4* NUMBER OP LAUNDRY SITES CONTACTED
AND SCHEDULED
SMSA
Composite
Sampling Frame
Contacted
Scheduled
New York
Los Angeles
Philadelphia
Chicago
Detroit
163 .
137
102
100
90
93
28
43
44
42
14- .
12 .
. 9
8
.7
Total
592
250
50
B-7
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developed is system la: equalization followed by dissolved air
flotation (DAF) «, The following units and equipment are included?
o equalization tank (above or below grade)
o dissolved air flotation (DAP)
o sludge handling or vacuum filtration unit
(only necessary for-flows over 48,000 gpd)'
o chemical storage
Table 2-5 presents space requirements for this system for a
range of industrial laundry waste water flows. For sites where
other operations take place, i.e.,. linen supply, diaper service,
etc., only the flow from industrial laundering was considered for
treatment. • ... . .
Where adequate space, was not readily available inside or
outside a laundry facility, the possibility of relocating
equipment to provide space was examined. Where no space could be
provided, the possibility of acquiring adjacent property foe the
location of treatment equipment was examined.
Although SO sites were scheduled, only 45 were successfully
surveyed. Once the survey personnel were in the field, two sites
were found t© not fit the required criteria? i.e., did not
conduct industrial laundering despite telephone confirmation of
such, and three sites refused admittance despite receipt of
Section 308 letters. Table 2-6 shows the breakdown of sites
visited and actually surveyed.
3.0 SURVEY RESULTS
Tables 3-1 through 3-5 present data on individual sites
surveyed in the five SMSAs.
The following items are presented in the tabless
o Number of employees - total number of plant employees
including office staff and drivers.
o Percent industrial — where other operations take place
at the same facility, this figure represents the
percent of total production (pounds per year)
attributed to industrial laundry.
o Industrial production - pounds per year processed.
B-8
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TABLE 2-5. SPACE REQUIREMENTS FOR TREATMENT OP
INDUSTRIAL. LAUNDERING WASTE WATER
Industrial Laundering
• Waste Water Flow
Space Requirement
for Treatment (sq.ft.)*
2,400
4,800
7,200
9,600
14,400
24,000
36,000
48,000
72,000
96,000
120,00.0
135,000
150,000
250,000
40
54
70
84
105
107
160
200
250
300
400
450
500
800
* Assuming equalization tanks below grade,
B-9
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TABLE 2-6„ INDUSTRIAL LAUNDERING SITES SCHEDULED
AND SURVEYED (SIC 7218)
asssssaasssBaaassBaasssssaasSssssssssass
SMSA
New York -
Los Angeles
Philadelphia
Chicago
Detroit
Totals
Number of
Sites
Scheduled
14
12
9
3
7
50
Sites Elimi-
nated in
Field
1
1 •
i« ma.
2
Number of
Sites Refusing Sites
Admittance Surveyed
2 11
12
1 ' 8
7
7
3 . 45
Jl
B-10
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o Industrial waste water flow - volume of. waste
water attributed to industrial production. Where
flow was not known, it was assumed to be proportional
to industrial production.
o Separate streams - where other operations take place,
existence or not of. segregated waste flows was
identified*
(1)
o Existing treatment - equalization, dissolved
air flotation.(2)
o Equalization capacity - where equalization exists,
the capacity is presented.
o Required equipment - an identification of
which units would be required at each site. Where
equalization already exists but is not of sufficient
capacity or could not be used because of mixing with
other wastes (i.e., linen wastes), it is indicated as
being required. Note; Most sites in Chicago have
treatment in place for industrial laundry wastes due to a
recent municipal regulation. Required treatment units
in the table reflect units added as a result of local
regulations.
o Space available - indicates interior or exterior
o Cost items — an identification of specific cost
items related to tlie location of a treatment system.
The items include:.
3- - housing required for exterior location,
, 4'— interior modification required such as
-••- relocating equipment or interior constraints
to excavation,
5 - acquisition of additional property,
6 - relocation of facility when no adjacent land is
available.
3*1 Cost Estimates
Following the survey, the costs for making or acquiring
space for each site not having readily available space were
developed.
o Housing — at $25 per square foot, construction of an
enclosure to house a.DAP unit.
B-16
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o Equipment relocation - all but one site requiring
relocation were for minor equipment. One site in
Chicago required relocation of major equipment and the
cost estimate is from plant management. For sites where
interior excavation would be required, an estimate of
excess labor costs was made based on excavation volume.
o -Acquisition of additional-property - only one site
required such. An estimate of property values in the
area was obtained 'from local authorities,,
o Relocation of facility - one site, surrounded by streets,
could not acquire additional space. No cost estimate was
made for relocating should it be required.
Table 3-6 - summarizes the survey findings by the type of
locational costs to be incurred by sites in each SMSAC
Table 3-7 presents the estimated costs to be incurred by
surveyed facilities without readily available space. Also
included in the table are estimated capital costs of treatment
for each facility as presented in the development document, and
the subsequent percent, increase in that cost due to additional
locational costs.
Not included in the cost estimates for any facilities are
.costs, for segregating waste streams or the additional cost for
placing equalization tanks below grade. The cost of segregating
industrial laundry wastes where other operations take place would
be minor, but could hamper operations at some small facilities.
-The additional cost of below grade equalization is estimated at a
maximum of 10 percent of the cost of an equalization tank above
ground.
i
3.2 Statistical Analysis of Survey Results
•
From the random sample of the five largest SMSAs, confidence
interval estimates were computed for the fraction of the industry
which is expected to be impacted by locational costs for waste
water treatment.
Stratified sampling parameters for each of the five SMSAs
-were-g-iven in Table 2-3. Results of the survey were given in
Table 3-6. For the purpose of interval estimates, those data in
.Table 3-6 are recapped in. Table 3-8 in terms of extensive,
moderater or no cost impact traceable to locational
:considerations.
Using standard stratified sampling estimation techniques
B-17
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TABLE 3-6. SUMMARY OP PROVISIONAL COSTS FOR INDUSTRIAL LAUNDERERS
1 TO ACCOMMODATE WASTE TREATMENT SYSTEMS
Modifications Required
SMSA Number
Faeilitie
Iff tsl 4m ^i
vi si tea
NY 11
LA 12
Phil. 8
Detroit 7
Chicago 7
Survey
Total 45
Average
per
Laundry
ts None Int
Minor
4 2 ($2, 000)
12
2 2($11,000)
1 2 ($8, 500)
1 1($5,000)
20 7
($26,500)
. $3790
erior Exterior
Facility
Ex ten- Land and Rel oca-
si ve. Housing Housing tion
3 ($13, 500) 1 ($35, 400) (1) —
•
4 ($38, 700)
4($57,000) .
1 ($100,000)4 ($47, 900)
1 15 .1 (1)
($100,000) ($157,000) ($35,400) ' —
$100,000 1, $10,1500 $35,400 —
(1)
No cost estimate made.
B-18
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TABLE 3-7. INCREASE IN CAPITAL COSTS DUE TO
ADDITIONAL LOCATIONAL COSTS
Facility
•-N-3-—
N-4
-N-5---
N-6
N-7 -
N-9
N-ll
P-l
P-2
P-3
P-4
P-5
,p-7 ...
C~l
C-2
C-4
C-5
C-6
C-7
D-l
D-2
D-3
D-4-.-
D-5
..D-6- .
Industrial
Plow (gpd)
Approximate
Capital Cost
of Treatment
Additional
Locational
Cost
Percent
Increase of
Cap. Cost
68 r 000
10,600
2,500
8,000 '
2,000
8,500
2,500
28,000
20,000
60,000
75,500
20,000
14,000
30,000
150,000
20,000
40,000
45,000
76,000
250,000
135,000
16,000
15,000
70,000
6,000
160,000
52,000
33,000
45,000
35,000
46,000
38,000
95,000
73,000
150,000
165,000
73,000
58,000
100,000
215,000
73,000
120,000
130,000
165,000
280,000
208,000
60,000
58,000
160,000
43,000
*-
7,350
3,750
35,400
2,400
1,000
1,000
10,000
7,350
14,000
8,500
. 2,500
7,350
10,000
100,000
5,000
10,900
10,900
16,100
31,250
7,500
7,500
. 1,000
14,000
4,400
*
14
10
79
7
2
3
10
10
9
5
3
13
10
46
7
9
8
10
' 11
4
12
2
9
10
* This site had no space and could not acquire adjacent
land. No cost estimate was made.
B-19
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TABLE 3-8. SUMMARY OF SAMPLE PROPORTIONS AFFECTED BY SPACE
REQUIREMENTS FOR EFFLUENT TREATMENT SYSTEMS (SIC 7218 ONLY)
Locational Costs
SMSA Stratum
Size
NY 48
LA 49
Phil. 34
Chicago 48
Detroit 44
Subtotal 223
Remainder
of U.S. 1020
Total 1243
Sample
Size
11
12
a _
7
7
45
Sampl ing. . None
Fraction
.229 4
.244 12
.235 2
.146 1
.159 1
.202 20
Moderate
5
0
6
5
6
22
•
Extensive
2
0
0
1
0
3
B-20
-------
based upon correction factors for finite strata f one obtains the
following statistics:
p =* 0.0699; estimated fraction of fives SMSAs
with extensive locational costs.
s » 0*0370; standard error of estimate p
T » 16; estimated number of laundries out of
223 with extensive locational costs.
The estimate p, above, is the point estimate. Assuming
normal approximation- to the sampling distribution of p, one can
calculate an upper confidence limit for Pj the fraction of the
five SMSAs affected. Since confidence intervals depend upon the
degree of, confidence specified, the following alternate interval
estimates are obtained:
Pr(0
-------
small as well as large facilities.
« Aooroxiraately seven percent of the industrial
llSndry facilities iS the five SMSAs will incur •
extensive locational costs.
4
a Aooroximately 93 percent of the industrial laundry
facilities in the five SMSAs will incur zero to
moderate locational costs.
and that nationwide, this impact may be even less.
>l
B-22
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Date of Visit_
Personnel
LAUNDRIES STJKVKX1 FORM
Name of Facility:_
Address:
Telephone s_
Contact:
Titlet
1. Classification of'Primary Business
SIC 7213 Linen Supply
SIC 7218 Industrial Laundry
2. Plant Operation
a. Total number of Employees
b. Hours of Washroom Operation
c. Days/Yr. of Washroom Operation.
3. Processes Used Approximate number of pounds processed annually
a. Water Wash Only
b. Dual-Process ' ,,_„___
c. Dry Cleaning Only ___
4. anrmal. Plant Production:
a. annual Poundage Processed
X. Percent Linen Supply.
2. Percent Industrial
3. Percent Other
(Family, Institutional, Diaper Service, Etc.)
4. Have you had any recent increases or decreases in
the percent of Industrial Laundry handled?
How much? (past year)
B-23
-------
5. Do you have the capability to handle future increases
in the percent, of Industrial Laundry? __
How ouch? _•
5. Water Usage and Flow Patterns
a. Hater Source
1. City
^ 2. Well
^ 3. Other
b. Estimate of daily water use for laundering
Source {meter reading, water bill, guess, etc.)
e* Peak washwater flow in gallons per minute
Source (sanitary distric surcharge, meter reading, ete).
d. Duration of peak flow
e» Pattern of flow ' ________«
LS
XL
• GPD
GPM
6. Effluent Discharge
a. If both, Linen Supply and Industrial Laundering are dones
1. are wastewater streams separate? o _
2. If not, how.can this be accomplished?
b. Method of Discharge
1» To- municipal sewer connection
2. Directly to surf ace water
7. In-Plant Controls
1. Lint screen
2. Catch, basin or sump {.size)
B-24
-------
3. Screen at bottom of catch, basin
4. Heat Reclaimer
5. Other (specify)
8. Wastewater Treatment
a. Is wastewater treatment practiced?
b» If "yes", please describes
c. Is wastewater recycled?
1. What percent?
Space Availability
(Please diagram all areas)
a. Readily available space (clear, unused areas)
• 1. Location (interior, 'exterior, basement, roof, etc.).
2. Distance from washroom equipment or available tank
Distance from sewer connection
3. availability of power and distance from power supply
availability of lights
Availability of heat . __
4. Will housing be,.necessary?- .--: • ±.-.-*-* "•." .^-. ... J:'---.^
b. If space is not readily available, then existing space, that could.Be
made available. -' . . ..
1. Location . • ;
2. Distance from equipment and sewer
B-25
':-^r--" ••;. •-•'T^S^ilS
-------
3. Availability'of utilities and distance from power supply.
4. Necessary modifications (briefly describe)
a. Movement of light equipment
b. Movement of heavy equipment^
c. Breaking through concrete
Walls
Floor
d. Can equipment necessary for performing'
modifications gain access to the area
)\
If not, what will have to be done to permit access
e. How will implementation of modifications--impact
plant operation?
s^~a«^^
f. Will housing of equipment be necessary?
c. If no space is available,tthen, space that can be. acquired;
1. Renting » ,
3
Leasing
•or Purchase ,
a. Location
b. Distance from equipment and sewer
c. Availability of utilities
10* Summary of Cost. Xtmes (piping, reinforcements, etc.!
B-26
jmyrnvag gjy?',^'_
-------
APPENDIX C
LAUNDRY WASTEWATER TREATABILXTY DATA
In the following tables, C-l through C-20, treatability data for the various
systems described in Section 7 are given:
o The data in Tables C-l through C-6 are given for industrial laundries
utilizing calcium choride coagulation and DAF.
o The data in -Tables C-7 through C-ll are given for Linen supply and
commerical laundries utilizing polyelectrolyte coagulation, DAF,
filtration and wastwater recycle.
o The data in Tables C-12 and C-13 are given for an industrial laudnry
utilizing alum coagulation, DAF, filtration, and wastewater recycle.
o The data in Tables C-l* and C-15 are given for an industrial laundry
utilizing ferrous sulfate coagulation and DAF.
o The data in Tables C-16 and C-17 are given for a linen laundry utilizing
ferric sulfate coagulation and DAF.
o The data in Tables C-l 8 and C-19 are given for a service laundry which is
a direct, discharger. The treatment system utilizes alum coagulation,
clarification, carbon adsorption, filtration and
chlorination/dechlorination.
o The data in Table C-20 is given for an industrial laundry utilizing calcium
chloride coagulation and DAF.
c-1
-------
TABLE C-l PLANT A
Concentration, mg/1
Qty
Pollutant Water
COD
TOC
TSS
Oil and grease
Phosphorus
Antimony
Arsenic
Cadmium
Chromium
Copper
Lead
Nickel
Selenium
Thallium
Zinc
Cyanide
Phenol (total)
Benzene
Carbon tetrachloride
1,1, 1-Trichloroethane
2,4,6-Trichlorophenoi -
Chloroform 0.0008
Dicnlorobenzenes
2,4-Dimethylphenol -
Ethylbenzene . . ' - -
Methylene chloride 0.007
Dichlorobromomethane 0.003
Naphthalene . -
Pentachlorophenol
Phenol
Bis(2-ethyihexyl)phthalate 0.018
Butyl benzyl phthalate
Di-n-Butyi phthalate 0.0007
Di-n-Octyl phthalate . - >
Anthracene/phenanthrene - *
Tetrachloroethylene ' 0.010
Toluene 0.0 10
Trichloroethylene
Influent
6,400
1,700
390
S31
869
515
596
* 4-1.6
0.09*
0.010
0.11
0.48
1.5
4.8
0.35
iO.OOl
< 0.040
3.7
0.057
0.78
0.003
0.002
0.018
0.0007
1.1
0.46
0.025
0.002
.9
0.098
1.2
04 t
.31
0.092
0.15
0.38
0.32
0.36
0.004
Effluent
3,200
690
98
144
149
125
155
1.7
< 0.010
0.002
< 0.002
0.27
0.50
0.13 -
0.25
0.002
0.050
0.23
0.054
0.76
0.005
0.001
0.014
0.003
0.0008
0.26
0.04*
0.002
Ostt.
• ot
0.027
0.042
0.22
0.019
0.033
0.066
0.33
0.38
0.006
C-2
-------
TABLE C-2. PLANTS
Concentration mg/1
Pollutant
PH
COD
TSS
Oil and grease
Antimony
Arsenic
Cadmium
Chromium
Copper
Lead
Mercury
Nickel
Thallium
Zinc
Phenol (total)
Chloroform
Ethylbenzene
Methylene chloride
Dichlorobromomethane
Isophorane
Naphthalene
N-Nitrosodiphenylamine
Phenol
Bis(2-ethylhexyl)phthalate
Di-n-Butyl phthalate
Diethyl phthalate
Tetrachloroethylene
Toluene
Trichloroethylene
City
Water
7.0
<0.020
<0.010
0.005
<0.050
<0.025
<0.010
< 0.0002
< 0.050
0.002
0.055
• .
0.030
-
0.020
0.015
-
-
-
—
1.2
0.005
0.005
0.007 ,
-
-
Influent
11.6
3,800
700
440
0.041
0.012
0.017
0.27
1.6
9.4
0.002
0.15
<0.005
4.5
0.016
0.010
0.26
0.54
-
0.19
4.0
1.8
0.60
-
•
-
0.88
0.75
0.21
Effluent
7.0
1,300
48
190
< 0.020
< 0.010
0.023
S.0.13
0.33
0.23
< 0.0002
< 0.050
< 0.005
0.20
< 0.001
0.008
0.11
0.50
—
-
0.79
0.62
0.12
-
0.29
-
1.0
0.79
0.030
C-3
-------
TABLE C-3. PLANT C
Concentration, mg/1
Pollutant
-pH -
IT
COD
tss
Oil and grease
Antimony
Arsenic
Cadmium
Chromium
Copper
Lead
Mercury
Nickel
Silver
Zinc
Phenol (total)
Chloroform
Ethylbenzene
Methylene chloride
Dichlorobromomethane
Naphthalene
Phenol
Bis(2-ethy IhexyDphthalate
Tetrachloroethylene
Toluene
City
water
7.3
<0.020
0.011
<0.002
<0.050
<0.025
<0.010
< 0.0002
<0.050
<0.015
<0.025
0.017
0.005
-
0.007
M
0.22
0.020
Influent
.11.3
3,200
520
760
<0.025
"0.013
0.05*
1.2
1.2
4.4
0.001
0.050
<0.029
"2.6
Oe028
0.035
1.0
0.11
~
0.10
0.084
2.*
Effluent
8.S
1,200
64
170
<0.020
0.012
<0.002
0.62
0.34
0.067
< 0.0002
<0o050
<0.015
< 0.068
0.56
0.009
0.97
6f\
.0
=.
0.48
0.10
0.005
24
el
C-4
-------
TABLE C-4. PLANT D
Concentration, mg/1
Pollutant
PH
BOD ^
COD
TOC
TSS
Oil and grease
Antimony
Cadmium
Chromium
Copper
Lead
Nickel
Zinc .
Cyanide
Benzene
Ethylbenzene
Bis(2-ethylhexyl)phthalate
Tetrachloroethylene
Toluene
City
water
7.7
<2
<5
2
<5
<5
<0.10
< 0.001
0.010
0.026
< 0.020
<0.01
0.09*
-
0.0*0
- .
-
-
0.010
Influent
11.7
2,*00
7,100
1,800
9*0
1,600
0.16
0.070
0.98
1.7
5.*
0.08
2.7
0.28
0.13
17.5
2.6
0.030
2.6
Effluent
9.3
1,000
2,000
500
100
230
0.31
0.003
0.57
0.15
0.11
-
-
0.29
0.20
-
1.0
0.98
0.90
C-5
-------
TABLE C-5. PLANT E
Contration mg/1
Pollutant
BOD-
COD3.
TOG
TSS
Oil and grease
Phosphorus
Antimony
Arsenic
Cadmium
Chromium
Copper
Lead-
Mercury
Nickel
Silver
Zinc
Cyanide
Phenol (total)
City
water
•
.
<20
„
-
0.005
<0.005
0.050
<0.020
<0.0001
<0.005
<0.001
<0.060
<0.050
Influent
1,700
4,900
460
900
230
13
0.12
0.011
0.060
0.30
i.O
3.0
<0.003
"0.080
0.008
2.0
0.2*
.0.10
Effluent
5*0
1,100
270
18
8*
23
0.029
-
<0.002
0.10
0.20
0.070
0.002
<0.005
0.019
0,060
0*53
0.32
C-6
-------
5
o S
i s
o
I
a
a
(M
O
\
a 9s S
•> m S m n o
S*a
' ft
«
ft
1
s ~
§
c?
S -
8
8 '» 8
I
i
U
I
07
-------
K
S
leemoegoooeoogoee i i i o 1000 to
5
I
O O «^
MM ooo
-------
TABLE C-8. PLANT H
Concentration, mg/1
Pollutant
pH
BOD-
COD^
TSS
Oil and grease
Cadmium
Chromium
Copper
Lead'
Nickel
Zinc
Phenol (total)
Chloroform
Methylene chloride
Dichlorobromomethane
Phenol
Bis(2-ethylhexyl)phthalate
Toluene
City
water
7.1
<6 .
2
<1
36
0.0003
<0.010
0.005
<0.003
<0.010
0.16
<0.001
0.006
0.007
0.008
_
-
0.007
Influent
10.9
850
2,*00
250
*30
0.010
0.060
0.15
0.11
0.025
0.43
0.13
0.020
-
-
0.030
9.0
0.025
Effluent
11.0
900
2,600
2SO
220
0.007
0.20
0.19
0.21
0.0*8
0.56
0.16
0.028
-
_
0.0*8
0.80
0.01*
c-a
-------
TABLE C-9. PLANT I
Concentration, mg/1
Pollutant
pH
r ,
COD5
Oil and grease
Antimony
Cadmium
Chromium
Copper
Lead
Mercury
Nickel
Zinc
Phenol (total)
o
Chloroform
Methylene chloride
Bis(2-ethylhexyl)phthalate
Toluene
City
water
7.4
<5
96
30
<0.002
0.0002
0.025
0.030
0.001
0.008
0.010
0.010
<0.001
0.020
-
0.020
0.017
Influent
9.9
780
1,700
400
0.014
0.003
0.038
0.095
0.038
<0.0005
<0.010
0.17
0.26
0.18
0.035
; 0.080
Effluent
9.6
820
490
110
0.010
0.003
0.015
0.070
0.047
<0.0005
<0.010
• 0-.065
0.055
0.022
0.030
0.040
C-10
-------
.3
•8
i
8 S S S
2 g
v v — • v
s
1 «
O O O
§
° o
I «
s 8
ooo<*ooo
§
V V V V
o o e
v v v
I
05
§
•a e o
S
S
if, o o o
K V V V
.1 S .5 - « 1 S
v v v
S I S
O O G O O O
v v v S v
u
C-ll
-------
TABLE C-ll. PLANT
. Concentration, mg/I
City
Pollutant water
Oil and grease
BOD,
5
COD
TOC
TSS
Phosphorus
Cyanide (total)
Phenol (total)
Antimony
Cadmium
Chromium
Copper
Lead
Nickel'
Silver
Zinc
1,1,1-Techloroethane
0
I
<10
2.5
-------
x
t-
i4
6
1
II
,1
ll
=3
t>
i
og
I
O <^
<*> o-«
\»oo o« WNO o e*
!s cs c» o ••
«•« o *^ •••
OOOOOOoOo— IO IOOOO lO
oo o oo « o o
~ i d d i d i d i d
, —
• o
.0 §
• did
moo m «
— o o
oa ON o o
• • • • • •
i oooo i e i o
§gg R 8 g
oo
i odd
o i o i o
4* o &• ••• O m N N N o o
5oSm rv vuo o c*o~ N o S
> ~ -id d d d "v i -= i vo d id t iddd to to 10
~vo « ooc
o« — oo <
\O
— I I IOOOO r lOOOIOIOOt
_«oo« oooo S
!ddddddd-A i i < dddd i i odd dodo id
S
o»
N<
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1S2 S ggg
ooooooooo— i i iooo looooo 10 iooo
, 1 S.I 9 i i ii
i d«ododddod odddodd i .id t i do 10 > 10 to i too
v vv v v v
I
i-s
Ifs|i|
lll|i?-
u
-------
TABLE C-13. PLANTK
(Data obtained from equipment manufacturer)
BOD
COD
Oil and grease
pH
Chlorine as Cl
Total dissolved solids
Total suspended solids
Volatile dissolved solids
Volatile suspended solids
Mercury
Cadmium
Lead
Sulfate, as SO^
Arsenic
Cyanide
Phenol
Total coliform, per 100 ml
Color, APHA color units
Carbonate, as CO3
Silicate, as 510$.
Calcium
Iron
Aluminum
Nickel
Zinc
Chromium
Total organic carbon
Copper
Antimony
Alkalinity as CaCOj
Ammonia nitrogen, as N
Nitrate nitrogen, as N
Sodium
Carbon dioxide, as CO2
Concentration, mg/1
Influent
180
1,290
175
10.64
<0.01
3,558
51
712
20
0.0010
0.02
OolO
1,590
<0.05
<0.01
0.046
<1
40
324
145
21
1.2
90
0.05
1.0
0.038
323
0.38
0.6
632
3.6
0.74
1,560
<0.1
Effluent
63
714
11
7.06
<0.01
3,650
16
409
3
<0.0005
<0.01
<0.01
2,330
<0.05
<0.01
0.033
<1
10
O ,09 A
78
23
0.38
1.7
<0.01
0.50
0.012
227
04 1
.13
0.6
97
3.7
0.83
1,540
16
•C-14
-------
-------
O
(<4 O O O SO
§<0
o
. i »
*^l T»^ '^™ ii
O O VJ "° *•*
0 m
v ^
1
ejJ
i;
.
Irt O «*• •««• >C
o o o o r» —
O fM
V JO
•&
0 •»
< S
H^
•S
«
I
S
i
g
o
g
s §
o
a
s &
f B
B!
Si
s
5
016
-------
s
1
5!
\a
3
I
1
3
1
Igfi ^^sa^sKj
•C-17 •
-------
i
o o «o o
s
a
oi
&s
iC
3
I
-».-*
s
S g S
Ift f^ ^*
S S g
? o o £.
I
- a o iv
o o a\ o
- §
o
&
-«" a »\ (?>
o o f» o
g
1 I I 1 1
-------
TABLE C-18. PLANT N
r
Concentration, mg/1
Pollutant
TOG
TSS
BOD-
COD^
Cyanide
Phenol
Antimony
Arsenic
Beryllium
Cadmium
Chromium
Copper
Lead
Nickel
Zinc
City
water
0.020
0.005
0.005*
<0.001
<0.002
<0.005
0.080
0.070
<0.005
0.060
Raw
wastewater
5*
2*0
62
232
0.020
1.9
0.0025
0.017
< 0.001
0.0*0
0.009
0.0009
0.30
< 0.005
0.30
Clarifier
effluent
0.020
53
0.0025
0.012
<0.001
0.060
0.0*0
0.001
0.080
<0.005
0.70
Filter
effluent
1*
22
19
85
0.020 .
7
0.0063
< 0.001
0.008
0.050
0.000*
' 0.030
< 0.005
0.60
c-ia
-------
TABLE C-19^ PLANTN
Concentration, mg/1
Pollutant
Oil and grease
BOD
5
COD
TOC
TSS
A Ww
Phosphorus
Cyanide (total)
Phenol (total)
Cadmium
Chromium
Copper
Lead
JtoW<*^»
Nickel
Silver
Zinc
Phenol
1,1,2,2-Tetrachioroethane
Chloroform
Methylene chloride
Dichlorobromomethane
Chlorodibromomethane
Pentachiorophenoi
Phenol
Bis(2-ethylhe3cyl) phthalate
Butyl benzyl phthalate
Di-n-Butyl phthalate
Di-n-Oetyl phthalate
Diethyl phthalate
Tetrachlproethylene
Toluene
Trichloroethyiene
Raw
wastewater
17
7
20
16
157
137
215
143
240
63
40
7.0
< 0.002
0.038
0.051
0.039
0.138
0.071
0.055
0.01*
0.609
0.0018
*"
•-
«
0,0006
-
. •
0,002
0..005
0.0005
Clarifier
effluent
7
1
5
3
60
*5
89
3*
125
*0
46-
1.6
< 0.002
0.-028
0.012
0.034-
0.031
0.066:
0.050
0.011
0.24*
0.002
0.07
0.03S
a.
-
0.002
0.067
0.36
0.007
0.005
0.10
0.003
0.012
Carbon
effluent
12
2
50
30
*5
17 '
136
38
78
2.0
< 0.002
0.029
0.015
0.036
0.0*2
0.065
< 0.036
0.007
0.212
0.001
0.018
0.003
• • "
•
0.003
Q.Q01
0.023
0.017
0.005
• 0.00*
0^032
0.00*
0.005
Filter
effluent
3
0
Q
o.
*1
11
2*
15
59
21
fOfi
37
• 0.9
<0.002
0.013
0.01*
0.025
0.032
0.031
0.037
0.007
0.24*
QArtrt^1
.0007
0.095
Ort \ rt
• u XW*
*
»-.
0.016
0.004-
0.003
0.002
0.031
0.006
0.003
C-2Q
-------
s
1
Lead
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«
an
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ft
p« o o o e
at at
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(*.(&'(*
« Oi ft
v m o»
M m rv o c> o p o o o o o
^<^•• ^oo \o(nt^o«^<*>fk'^
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cs rt
PS
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ft Ct
,»4rfN^«**'^<'>t*«
id
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0)
1
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o
-------