Note: Descriptions are shown in the official language in which they were submitted.
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COOKING OIL SALVAGE ~iYSTEM
BAC~CGROI~D OF THE INVENTION
The subject invention is in the field of disposal
- systems and is more specifically directed to a unique
system for receiv:ing and storing for subsequent collection,
spent or used cooking oil from a restaurant or the ~ike.
The handling of spent cooking oils for disposal pur-
poses in restaurants has normally been effected manually
by the draining of such oils into receptacles which are
eith~r manually carried or conveyed on dollies or other
~ vehicles to outdoor storage containers. The hi~h tempera-
ture of such oils, which can exceed 300F., presents sub-
stantial safety hazards to workers and oehers ~n the
vicinity who may be aceidentally burned. Additionally,
1~ the hea~y weight of such oil frequently result~ in other
injuries, such as back sprains, ant ~he like.
In addition, spent cooking oil m~y be sold for re-
processing. Ho~ever, in order to do so, it is necessary
that the oil be collected and maintained in a fashion that
allows its ready rcmoval from the premises of the restaur-
ant where the oil has been used. To date, spent cooking
oil has norma}ly been stored outside of the restaurant in
open drums having removeable lids or at best, in drums
stored inside drum cabinets. Because the security provided
for these drums is minim~l~ the oil is often contaminated
by waste refuse or various animals. Where drum storage
cabinets are used, in most cases, after a few months of
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use, the cabinets have been seriously damaged during xe-
moval of the drums. Normally, when these drums are full of
waste storage oil, they are picked up by oil renderer's
trucks and transported to the ~actory for processing.
However, the drums are extremely heavy and difficult to
handle. In some instances, the drums have been overturned
and the contents spilled on the restaurant's par~ing area
in attempting to load them onto the truck. The cooking oil
salvage system of the instant invention provides security
for cooking oils. In the past, waste cooking oil has been
extremely valuable and ha6; often been stolen. The tank of
the instant invention subs;equently reduces or eliminates
this problem. Secondly, by storing cooking oil outside of
the restaurant in a closed, controlled access container,
internal and extexnal restaurant housekeeping and sanitation
problems normally associated with waste cooking oil are
eliminated. For example, previous extern~l storage con-
tainers often leaked onto black-top surfaces, causing severe
degra~ation. In the past, health department rules often
made difficult the storage of waste cooking oil within the
restaurant facility. Moreover, by storing the oil in a
closed and sealed container, rodents, insects and solid
cont~minants are eliminated and potential external and
internal sewer clogging from waste oil discharge is elimi-
nated. Additionally, the cooking oil salvage system of theinstant invention provides a cost saving means for the
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restaurant op~rator by increasing the amount of usable
internal restaurant space and by providing an additional
source of money from the sale of an upgraded salvaged
cooking oil. Because this system provides an exact account-
5 ing of all cooking oil supplies, it substan~ially reducespilferage by store employees. Finally, becauce virtually
all possibili~y of oil rontamination during storage is
eliminated, the oil itself may be reused, for example, as
an additive for soaps, cos~metics, animal foods, plastics,
~tc.
Thereore, it is an o'bject of this invention to pro-
vide a new and improved me,ans for handling and disposing
of spent or used cooking oils.
It is another object of this invention to provide a
method for readily storing for sale spent cooking oil, so
that it may be removed from the restaurant in a convenient,
easy-to-handle fashion.
These and other objectives ~re obtained by utilizing
the system of the instant invention.
20 SUMM~RY OF INVENTION
Achievement of the foregoin~ objects is 0nabled by the
preferred embodiments of ~he invention through the provision
of a receiver means mounted inside the building from which
the spent or used cooking oils are to be removed. The
receiver means is connected to a transfer conduit extending
through one of the walis of the building and having an
outer termination external of ~he building comprising a
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connection to an insulated holding tank permanently
mounted outside the building. The holding tank may be of
cylindrical construction and is provided with an electric-
ally-powered heater means to maintain the temperature of
5 oil in the holding tank at a desired ~emperature above the
solidification temperature o~ the particular cooking oil.
Used cooking oil is discharged from the holding tank by
means of a discharge tube inserted into the tank. Used oil
whîch is maintained at pumping viscosity by the heater is
1~` periodically collected by connecting a hose to the discharge
tube And pumping the liquid into a collection vehicle such
as a tank truck.
A better understanding of the ma~ner in which the pre-
fe~red embodiments achieve the objects of the invention will
15 be ~nabled when the following detailed description is con-
sidered in conjunction with the appended drawings in which
like xeference numerals are used for the same p~rts as
shown in the different figures.
BRIEF DESCRIPTION OF THE DRAWTNGS
Fig. l is a sectional view of the in~ention.
Fig. 2 is a partially cut away front view of the
invention.
Fig. 3 is a diagrammatic side elevation with parts
in phantom of a deep fat pressure fryer and a Collectra-
matic~ filter floor dolly illustrating one method of
draining the oil from the cooker and pumping it into the
holding tank.
3~
Fig. ~ is a side elevation of the prior art method of
emp~ying the contents of ~he pressure cooker or fryer into
a stock pot.
Fig. 5 is a side elevation, diagrammatically illu5-
trating the method of puD~ing oil from the holding tank intothe tank truck.
DESCRIPTION OF THE PREFER~D EMBODIMENT
Fig. 1 of the drawin~;s illustrates the preferred
embodiment of the inventive cookin~ oil salvage system,
generally designated 10, ~ich is shown in conjunction with
a building wall 12 which will normally be an external wall
of a restaurant or the like. The s.ystem may include a
receiver slnk 14, preferably formed of stainless steel,
and including a removable filter screen not shown. In an
alternat_ve arrangement, a simple drain pipe 16 or receiver
means may replace the r~ceiver sink, in which case a
regular dolly oil filter may be employed to pump fil~ered
oil from deep fryers in the restaurant directly into the
pipe and thus into the cooking oil salvage system.
This method is illustrat~t in Fig. 3 in which a floor
dolly 55 is positioned with its basin 56 directly below
the drain valve 53 of the pressure fryer 52. The hot oil
drained therefrom can be pumped through the filtering
system located in the vertical portion 57 of the floor
25 dolly 55 snd pumped via wand or probe 58 back into the
ccoker 52. The wand or probe has an insulated handle 60
~Z~1634
welded a~ point 59 to the wand so as to be offset there-
from and prevent scalds or burns to the party handling
~he wand.
After the oil has been used for a suf~icient time to
become rancid or, after l;he fat~y acid concentration has
reached or surplassed an alcceptable limit, the oil is dis-
carded again by draining the oil from ~he fryer 52 through
ehe drain valve 53 into t:he basin 56 of the floor dolly 55.
The floor dolly 55 is then pushed toward the building
wall 12 and the end of the wand 58 is inserted into the
horizontally disposed col~duit 16 e~tending through the
vertically disposed wall so as to pump the hot and fil-
tered used oil into the holdin~ tank 20. Since the hold-
ing tank 20 i5 located within the tank housing 24 which is
filled wi~h insulation 26, the heat of the oil is not
rapidly lost. However, in cold weather, the heating ele-
ment 42, con~rolled by the thermostatic control 44 can
maintain the oil at any desired temperature.
Dolly filters or floor filters are commercially
available from Collectramatic, Inc. of Louisville,
Kentucky, Mies Filter Products of West Bend, Wisconsin,
and Dean IndustriPs of Culver C~ty, California. The hot
oil is drawn from the cooker, f~l~ered free of all partic-
ulate matter, and pumped via a tube and nozzle ~known in
the trade as a wand) of the dolly filter back to the
cooker. Whenever the free fatty acid of the oil reaches
l634
or exceeds 1.5%, the oil must be discarded, since a
rancid taste is then imparted to the food. It is at this
time that the operator drains the cooker of the hot,
rancid oil into the dolly filter, and then rolls the
5 dolly filter tc~ the wall adjacent to pipe 16. He then
pumps the oil, filtered Eree from all particulates, through
the wand into the pipe 1l5 or storage in the ~ank 2G. In
some fast food establishments, dolly filters are not used.
o In these es~ablishments, the hot oil is dralned through
lO a large funnel-shaped fi'Lter into a five~gallon s~ock pot
with handles on either siLde. The employees then must
pour the polished or fill:ered oil ~ack into the cooker.
Prior to this invention, if the oil had become rancid,
it became necessary for him to carry ~he hot oil, holding
15 it at arms length away ~rom his body, to the drum storage
area where it was to be s~ored. This was usually at ~he
rear of the parking lot. According to this inven~ion,
~he distance to which the hot oil had to be carried was
much reduced. It was now only from the covker to the
20 sink 14 on the inner surface of the wall - rather than
from the cooker to clear across the parking lot. Since
most fast food restaurants employ teenage workers a~
minimum wage, and, since it is necessary to hold the hot
stock pot of oil away from his body for some d~stance,
25 prior to this invention, it was not uncommon for some of
the hot grease to splash over the side and spill onto the
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lZ1163~
worker, causing serious second and even third de~ree
~urns. This was particularly true in a busy ~staurant
where the worker had, in effect, to open up the door with
his foot or with his back, holding the four or five
gallons of 300~F. oil at ~Eull arms length away from his
body and make the trip to the drum storage ar~a. A mis-
step, or a slip, could and did cause young employees
serious and painful injur:ies.
According to a preferréd em~odiment of this inven-
tion, spent oil ls pumped via the wand of the filter
dolly Lnto pipe 16 and flows outwardly through the trans-
fer conduit 16 extending through the wall 12 and into the
interior of a cylindrical holding tank 20 permanently
- mounted on foundation 22. The holding tank is mounted on
15 i~s cylindrical side, preferabiy parallel to the sides of
the building. The tank is placed inside a tank housing
24 whieh is provided with insulation 26 preferably sur-
rounâing the tank 20 itself. In addition, it is preferred
that ~he transfer conduit 16 coming through the building
wall not be exposed to e~terior elements, but rather that
the tank housing be mounted flush against ~he wall area
where the transfer conduit penetrates the wall~ so that
any oil flows directly from the inside of the building
~hrough the wall 12 to the inside of the tank housing.
25Fig. ~ illustrates the prior art method of draining
the pressure fryer or cooker through drain valve 53 into
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stock pot 50. In this embodiment, ~he stock pot ~an be
manually picked up and carried to the building wall 12
and poured into the receiver sink 14. Thus, the hot oil
will run through conduit or pipe 16 to the holding tank
5 20 inside of the tank housing directly adjacent to the ex-
terior building lwall 12 as previously indicated.
As is illustrated in Fig. 5, the holding ~ank can be
emptied easily and quickly by connecting a hose to discon-
O nect coupling 38. A pump P and meter are diagrammatically
10 illustrated in the hose 63 leading to tank truck T.
Since the oil is filtered and can be maintained clean
and ~ree of contaminants, the oil collector or renderer
can determine exactly how much high-grade oil has been
pumped into his truck~ The restaurant operator gets top
15 tollar for his waste oil and the safety and housekeeping
problems encountered with open drum storage are eliminated.
The system will normally be positioned in the building
in ~n area convenient eo the deep fat cooking rea so as to
be convenien~ly located for receiving the spent or used
20 cooking oil. The spent or used cooking oil can be deposited
in the sink 14 by pump and con~uit means, or from manually
positioned containers or stock pots or preferably by pump-
ing the oil directly from the deep fryers via the wand or
probe of a dolly oil filter and pump of conventional design
25 through conduit 16 horizontally disposed in the verti~al
ex~erior wall 12 to the holding tank 20 disposed in the
insulated housing 24 directly adjacent to the buildlng.
ThP transfer conduit 16 extends through the top of
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the holding t~nk 20 to permit direct dischar~e of used
cooking oil directly into the interior of the tank. For
easy acces~ to the tank itself and to the dis~har~e tube
30, a service door 28 may be provided, for example, on
the top of t~e housing. Side service doors may also be
included to facilitate cleaning and maintenance. In a
preferred embodiment, a service door latch means 32 is
located inside the building. The latch is engagable in
a latch receiver 34 on ~he sexvice door. Since the latch
is operable only from th~ inside of the buildin~, access
to the cooking oil salvage system is not permit~ed except
with permission of the store occupants. As a result,
urther protec~ion against cooking oil pilferage or damage
to the salvage system is provided.
A discharge tube 30 is shown in Fig. 2, which in-
cludes a valve to be opened to permit the pumping of the
contents of the tank to a collection ~ehicle. The dis-
char~e tube extends nearly to the bottom of the holding
tank, ~o tha~ virtually all of the used cooking oil m~y
~0 be pumped ~rom the tank into the collection vehicle.
Connected to the end of the ~ischarge tube is a flexible
hose 36 provided with a quic~ disco~nect coupling 38,
coupling onto a corresponding receiver hos~e on the col-
lection vehicle. For drainage and cleaning, a gravity
discharge petcock 40 is provided at the bottom end of the
~ank, to allow complete drainage of the tank when cleaning
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is necessary. The tank is also provided with a heating
element 42, wrapped around at least a portion and prefer-
ably all of the tank. It i~ preferable to ma mtain the
contents of the tank at flowable viscosities, usually at
5 temperatures in the range of about 105F. to 110F.
Normally, with a llO-gal:Lon tank, a 350-watt heating
cable is sufficient, whiLe with a 220-gallon tank, a 700-
watt heating cable is required. The heating cable is pro-
vided with a thermostat control means 44 to m~intain the
temperature of the cooking oil at the desired temperature.
In order to insure tha~ t:he tank is no~ over filled, an
automatic shut-off valve 47 or warning indicator electric-
ally connected to a light 49 inside the restaurant is pro-
vided. ~egartless of which embodiment is chosen, a fluid
level measurement means 46 is provided. This measuremRnt
means either activates a light 49 or closes a valve 47
located preferably on the transfer conduit 16 when the
cooking oil reaches a predetermined helght in the tank.
In addition, in order to protect the inside of ~he tank
housing from excess cooking oil, an overflow pipe 48 is
provided to discharge excess oil.
In use, the cooking oil saivage system of the instant
invention is gradually filled with used cooking oil. At
periodic i~tervals, the conten~s of the tank are pumped
from the tank into a bulk cooking oil salvage vehicle, such
as a tank truck, and sold. In this manner, a safe and cost-
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effective storage recovery of used cooking oil is pro-
vided. By using this system, restaurants may make hun-
dreds of dollars a year in the form of sales ~f used
cooking oil, while at the same time~ restaurant employees
are protected from dangerous hot cooking oil.
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