U.S. patent number 3,913,633 [Application Number 05/516,738] was granted by the patent office on 1975-10-21 for liquid dispensing and vapor recovery system.
This patent grant is currently assigned to Weil-McLain Company, Inc.. Invention is credited to Trueman W. Hiller.
United States Patent |
3,913,633 |
Hiller |
October 21, 1975 |
Liquid dispensing and vapor recovery system
Abstract
A liquid dispensing and vapor recovery system in which an
underground storage tank is connected to a first conduit for
delivering a liquid, such as gasoline, to a vehicle gasoline tank,
or the like, under the force of a pump disposed in the storage
tank. A second conduit is connected to the first conduit and to the
storage tank for diverting a portion of the gasoline in the first
conduit back to the storage tank while forming a reduced pressure
zone in the second conduit. A recovery vessel is connected to the
vehicle tank for receiving the vapors from the latter tank and
separating same into relatively heavy and relatively light
portions. The heavy vapors are passed directly into the storage
tank and the light vapors are drawn into the second conduit and are
partially absorbed by the gasoline flowing in the latter conduit
before being passed into the storage tank.
Inventors: |
Hiller; Trueman W. (Bettendorf,
IA) |
Assignee: |
Weil-McLain Company, Inc.
(Dallas, TX)
|
Family
ID: |
24056886 |
Appl.
No.: |
05/516,738 |
Filed: |
October 21, 1974 |
Current U.S.
Class: |
141/45; 55/459.1;
222/318; 96/195; 96/220; 55/338; 141/59 |
Current CPC
Class: |
B67D
7/0484 (20130101) |
Current International
Class: |
B67D
5/01 (20060101); B67D 5/04 (20060101); B67D
005/04 () |
Field of
Search: |
;222/72,318
;141/7,8,37,43,45,50,52,53,59,123,290 ;220/85VR,85VS
;55/184,338,459 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Reeves; Robert B.
Assistant Examiner: Rolla; Joseph J.
Attorney, Agent or Firm: Lane, Aitken, Dunner &
Ziems
Claims
I claim:
1. A liquid dispensing and vapor recovery system comprising storage
means for said liquid, first conduit means adapted to connect said
storage means to receptacle, and pumping means for pumping said
liquid from said storage means through said first conduit means and
to said receptacle, wherein the improvement comprises second
conduit means connected to said first conduit means and to said
storage means for diverting a portion of said liquid in said first
conduit means back to said storage means, means for forming a
reduced pressure zone in said second conduit means in response to
liquid flow through said second conduit means, a recovery vessel
for receiving the vapors from said receptacle and separating said
vapors into a relatively light portion and a relatively heavy
portion, and means connecting said vessel to said reduced pressure
zone for drawing the relatively light vapors from said vessel
through said second conduit means for passage into said storage
means, said recovery vessel being directly connected to said
storage means for directly passing said relatively heavy vapors
into said storage means.
2. The improvement of claim 1 wherein said means for forming a
reduced pressure zone comprises a nozzle and a venturi disposed in
said second conduit means.
3. The improvement of claim 1 wherein said relatively light vapors
mix with said liquid in said second conduit means.
4. The improvement of claim 1 further comprising a dispensing
device connected to said first conduit means for dispensing said
liquid from said first conduit means into said receptacle and
connected to said vessel for drawing vapors from said
receptacle.
5. The improvement of claim 1 wherein said liquid is fuel, said
storage means is an underground storage tank, and said receptacle
is a vehicle fuel tank.
6. The improvement of claim 1 wherein said vessel is adapted to
separate said vapors by cyclone separation.
7. The improvement of claim 1 wherein said vessel includes means
for creating a relatively high velocity draw of vapors into said
vessel.
8. The improvement of claim 1 wherein said second conduit means is
in open communication with said first conduit means and said
storage means for continuously diverting a portion of said liquid
in said first conduit means back to said storage means.
9. The improvement of claim 1 further comprising condenser means
having an inlet connected to said recovery vessel and an outlet
connected to said second conduit means, said condenser adapted to
receive vapors from said recovery vessel, condense said vapors into
liquid, and pass said liquid to said second conduit means.
Description
BACKGROUND OF THE INVENTION
This invention relates to a liquid dispensing and vapor recovery
system and, more particularly, to such a system in which liquid is
dispensed from a storage tank to a receptacle while vapors from the
receptacle are drawn to the storage tank.
With the increased emphasis on preventing pollution of the
atmosphere, attention has been directed to minimizing the
introduction of gasoline vapors into the atmosphere from both
permanent type underground storage tanks for the gasoline, and from
the vehicles to which the gasoline is ultimately dispensed.
Gasoline vapors can easily be recovered from underground storage
tanks by providing a separate vapor return line which connects the
storage tank to the transport truck which periodically fills the
tank. In this manner, the gasoline introduced into the tank from
the transport truck will displace the vapors and force them through
the vapor recovery line to the truck whereby they are ultimately
disposed of either by burning or through compression -
refrigeration systems.
However, it has been extremely difficult to devise a satisfactory
vapor recovery system from the gasoline tanks of vehicles due to
the fact that the configurations of the tanks vary to a wide degree
and to the fact that many of the tanks have open vents in their
fill necks which allows the vapors to be displaced through the
vents to the atmosphere during a fill cycle. This problem may
become even more acute since some state and federal regulations may
very well ultimately require full recovery of vapors from existing
automobile gasoline tanks, whether vented or not.
Previous proposals to recover the gasoline vapors from automobile
tanks have included what is commonly referred to as a balanced
displacement system in which the gasoline entering the tank forces
the vapors through a separate line to the storage tank. However,
this system has been less than satisfactory, largely due to the
difficulty in creating a proper seal between the gasoline
dispensing and recovery nozzle and the automobile tank.
Although it has also been suggested to use a vacuum pump along with
a compressor and chiller assembly to remove the vapors from the
vehicle tanks, this type of installation has proved to be
relatively expensive and therefore impractical.
In copending U.S. patent application Ser. No. 400,555, filed by
Kirk Fowler and Elmer M. Deters on Sept. 25, 1973, and assigned to
the same assignee of the present invention, a gasoline dispensing
and vapor recovery system is disclosed which overcomes the
above-mentioned problems by providing an injector for establishing
a reduced pressure zone in response to fluid flow from the storage
tank to the vehicle receptacle, with the reduced pressure zone
functioning to draw the vapors from the receptacle back to the
tank. Although this design has proven to be satisfactory, the size
limitation of the injector has imposed limitations on the capacity
of the system, thereby preventing use of the system in relatively
large installations.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide a
liquid dispensing and vapor recovery system in which liquid is
dispensed from a storage tank to a receptacle while vapors in the
receptacle are recovered and delivered back to the storage
tank.
It is a further object of the present invention to provide a liquid
dispensing and vapor recovery system of the above type in which an
injector is used to create a vacuum in response to the dispensing
of the liquid from the storage tank to the receptacle, and is
utilized to draw the vapors from the receptacle back to the
tank.
It is a further object of the present invention to provide a liquid
dispensing and vapor recovery system of the above type which can be
used in relatively large installations yet utilizes an injector of
a relatively small size and capacity.
It is a more specific object of the present invention to provide a
liquid dispensing and vapor recovery system of the above type in
which a recovery vessel is provided in the line connecting the
vehicle tank to the storage tank for receiving the vapors from the
vehicle tank and separating them into relatively light portions
which are fed to the injector, and relatively heavy portions which
are fed directly to the storage tank, to thus enable an injector of
a relatively small size and capacity to be utilized.
It is a further object of the present invention to provide a liquid
dispensing and vapor recovery system of the above type which is
relatively simple in operation and relatively low in cost.
Toward the fulfillment of these and other objects, the system of
the present invention comprises storage means for the liquid, first
conduit means adapted to connect said storage means to a
receptacle, and pumping means for pumping said liquid from said
storage means through said first conduit means and to said
receptacle, wherein the improvement comprises second conduit means
connected to said first conduit means and to said storage means for
diverting a portion of said liquid in said first conduit means back
to said storage means, and means for forming a reduced pressure
zone in said second conduit means in response to liquid flow
through said second conduit means, a recovery vessel for receiving
the vapors from said receptacle and separating said vapors into a
relatively light portion and a relatively heavy portion, and means
connecting said vessel to said reduced pressure zone for drawing
the relatively light vapors from said vessel through said second
conduit means for passage into said storage means, said recovery
vessel being directly connected to said storage means for directly
passing said relatively heavy vapors into said storage means.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial schematic, partial elevational view of a
service station installation having a gasoline dispensing and vapor
recovery system of the present invention utilized therein; and
FIG. 2 is an enlarged, partial sectional, partial elevational view
of a portion of the installation of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As an example of the use of the liquid dispensing and vapor
recovery system of the present invention, it will be described in
connection with a gasoline dispensing installation for use in
service stations or the like. Such an installation is illustrated
in FIG. 1 and includes an underground tank 10 for storing a
quantity of gasoline which is delivered to one or more pedestals 12
through delivery lines 14 and 14a, under the force of a submersible
pump unit 16 disposed in the tank.
A casing 18 is attached to the tank 10 and extends upwardly
therefrom to connect the tank to a discharge head, or manifold, 20
which is preferably disposed below ground level in a well 22.
The pedestals 12, the pump 16 and the manifold 20 are all described
in detail in U.S. Pat. No. 3,183,723. Therefore, for the
convenience of presentation, the structural details of these units
are not shown in the drawings and will be described only generally
as follows.
The pump unit 16 is an electrical operated centrifugal type which
operates to draw the gasoline into the unit through a plurality of
intake ports disposed at the bottom thereof, and to force the
gasoline upwardly around a sealed electrical drive motor to the
manifold 20, in a conventional manner.
The manifold 20 supports the upper portion of the pump unit 16
while permitting the electrical connections for the drive motor to
be brought outwardly for connection to the proper controls. It is
understood that an adapter unit, or packer, is supported within the
manifold housing and has an inlet chamber communicating with the
outlet of the pump unit and an outlet chamber adapted for
registration with the line 14. The packer also includes a port
between the inlet chamber and the outlet chamber which cooperates
with a check valve to permit the flow of gasoline from the pump 16
to the line 14 while preventing flow in the opposite direction,
also in a conventional manner.
An injector assembly 30 is connected in the line 14 between the
manifold 20 and the pedestals 12 and is better shown with reference
to FIG. 2. In particular, the injector assembly 30 is preferably
disposed below ground level in a well 32 and is connected to the
line 14 by a by-pass conduit 34 which registers at one end with the
line 14. As a result, upon flow occurring through the line 14, a
portion of the gasoline is diverted through the conduit 34 and to
the injector 30. A nozzle 35 and a venturi 36 are formed in the
injector 30 in communication with the by-pass conduit 34 to form a
reduced pressure zone at the throat portion of the venturi in a
conventional manner. A conduit 37 registers with the outlet of the
venturi 36 and extends into the tank 10 where it terminates near
the floor thereof. A conduit 38 is connected to the injector 30 and
communicates with the nozzle 35 and with the above-mentioned
reduced pressure zone. The other end of the conduit 38 is connected
to an underground recovery vessel 40, to be described later.
As shown in FIG. 1, the line 14 extends from the manifold 20 to the
vicinity of each of the pedestals 12 whereby it is connected to
same via branch lines 14a. In a similar manner, the recovery vessel
40 is connected to the pedestals 12 by means of a line 42 and
branch lines 42a.
A hose assembly 44 extends from each of the pedestals 12 with each
assembly including an inner hose surrounded by a spaced, coaxial,
outer hose. As shown schematically in FIG. 1, the inner hose of
each hose assembly 44 is connected to the gasoline delivery line
14a and the annular space between the inner hose and outer hose is
connected to the vapor recovery line 42a within each respective
pedestal 12. A dispensing unit 46 is connected to the free end of
each hose assembly 44, it being understood that each unit 46
includes a dispensing nozzle connected to the inner hose of its
respective hose assembly and a vapor recovery conduit connected to
the annular space between the inner and outer hoses of each
assembly. Also, each dispensing unit is operated by a manually
operated valve 46a, in a conventional manner.
A support and switch assembly 48 is associated with each pedestal
12 and is adapted to support its respective dispensing unit 46,
with the switch operating to actuate the pump unit 16 upon release
of the dispensing unit 46 therefrom in a conventional manner.
Although not shown in the drawings, it is understood that the
pedestals 12 can be provided with the proper linkage, interlock
valves, meters, etc., in accordance with conventional designs.
As shown in FIG. 2, the recovery vessel 40 is disposed in the well
32 and is in the form of a cyclone separator having an inlet 52
connected to the vapor recovery line 42, a first outlet 54
extending below the well 32 and emptying directly into the storage
tank 10, and a second outlet 56 connected to the line 38 extending
to the injector 30. It is understood that the vessel 40 operates in
a conventional manner to create a centrifugal action which causes
the relatively heavy vapors entering the inlet 52 to fall to the
bottom of the vessel and pass directly into the tank 10. Also, the
relatively light vapors will tend to rise in the vessel and exit
through the outlet 56 into the line 38 for passage into the
injector 30. A plate 58 having a slot 60 formed therethrough is
provided in the upper portion of the vessel 40 to create a high
velocity draw through the vessel and thus promote the introduction
of the vapors from the vehicle tank shown schematically in FIG. 1,
through the line 42, and into the vessel.
A check valve 62 is provided in the line 14 to insure that gasoline
flow will occur only in the direction indicated by the solid arrows
in FIG. 2, while a check valve 64 is provided in the line 38 to
insure that vapor flow through the latter line will occur only in
the direction indicated by the dashed arrows in FIG. 2.
In operation, upon an operator releasing one of the dispensing
units 46 from its support and switch assembly 48 on a pedestal 12,
the pump unit 16 will be actuated to pump gasoline from the tank 10
through the manifold 20 and the line 14 to the pedestal 12. From
the pedestal 12 the gasoline will pass through the inner hose of
the delivery hose assembly 44 whereby, upon manual actuation of the
valve 46a associated with the dispensing unit 46, it will be
introduced into the gasoline tank of the vehicle.
A portion of the gasoline flowing through the line 14 will be
diverted through the line 34 and will pass into the injector 30
where it passes through the nozzle 35 and the venturi 36 before
passing into the line 37 and back to the tank 10. As a result, a
reduced pressure zone will be formed in the injector 30 which is
transferred, via the line 38, the recovery vessel 40, and the lines
42 and 42a, to the annular space between the inner and outer hoses
of the delivery hose assembly 44.
This reduced pressure zone, plus the force of the gasoline as it
displaces the vapors from the vehicle tank, will cause the vapors
to pass from the tank into the space between the inner and outer
hoses of the delivery hose assembly 44, through the lines 42a and
42, and into the vessel 40. In the vessel 40 the vapors will be
subjected to a centrifugal action which causes the relatively heavy
vapors to pass downwardly and out through the exit 54 directly into
the storage tank 10. The relatively light vapors will tend to rise
in the vessel 40 and will pass through the slot 60 in the plate 58,
through the outlet 56, and into the line 38 for passage into the
injector 30. In the injector 30, the vapors pass through the nozzle
35 and the venturi 46 where they are partially absorbed by the
gasoline entering the injector 30 from the line 34. The resulting
mixture then passes from the injector 30, through the line 37 and
into the lower portion of the tank 10 where even more absorption
will occur as the vapors rise upwardly through the gasoline in the
tank. In this manner, some absorption of the vapors is achieved
while permitting an injector of relatively low capacity to be
used.
At the tank 10 the vapors supplied to the tank directly from the
recovery vessel 40, as well as those from the line 37 that were not
absorbed, will either condense of will be recovered by the
transport truck for supplying gasoline to the storage tank in the
manner discussed above.
In addition to the advantages discussed above, it is noted that, in
the event of a failure of the injector 30, the recovery vessel 40
will enable the system to revert to a balanced displacement system
in which the vapors would be drawn to the tank 10 solely by virtue
of their displacement from the vehicle tank, thus minimizing any
potential damage to the system. Also, the vapor recovery system of
the present invention limits the amount of negative pressure of
vacuum that will be applied to the vehicle tank by virtue of the
recovery vessel 40, thus eliminating the chance of damage to the
tank.
According to an alternate embodiment of the present invention, an
optional condenser system 70 may be provided which receives excess
vapors from the recovery vessel 40, via a line 72, and condenses
the vapors in accordance with conventional practice, before passing
same through a line 74 back to the line 37 for passage into the
tank 10. Since this type of condenser system is well known in the
art, it will not be described in any further detail.
It is thus seen that the present invention provides an effective
and safe means of recovering vapors in a vehicle tank without
polluting the atmosphere.
It is understood that several modifications may be made in the
foregoing system without departing from the scope of the invention.
For example, the system can be adapted for vapor recovery only by
simply terminating line 14 at the vicinity of the check valve 62 to
permit all of the gasoline pumped from the tank into the line 14 to
be passed through the injector 30. Also, the system of the present
invention is not limited to the dispensing of gasoline and the
recovery of gasoline vapors but could be applied to any
installation, such as chemical plants, or the like, in which vapor
recovery is desired.
Of course, variations may be made in the foregoing system without
departing from the scope of the invention as defined by the
appended claims.
* * * * *