Vapor disposal system

Abstract

Apparatus is disclosed particularly suitable for use at automobile and truck fuel tank filling stations, at tank truck loading stations and other storage and dispensing facilities, and preferably utilizing the pressure attendant upon the handling of combustible vapors such as those of gasoline, fuel oil, jet fuel, and other volatile combustible liquids, separating the vapor from the combustible liquid, and smokelessly burning the combustible vapor. The structure for burning is adapted for disposal of vapors over a wide fluctuation of firing rates and compositions, and has provisions to avoid flash back, to protect the system in the event of excessive operating temperatures and provisions for noise reduction.

Parent Case Text

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of my prior application for Vapor Handling Equipment and Vapor Disposal Unit Therefor, filed Dec. 8, 1972, Ser. No. 313,504, now abandoned.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to vapor disposal systems especially adapted for vapors of hydrocarbon fuels including collecting and separating apparatus and provisions for safe disposal of the vapors by smokeless combustion.

2. Description of the Prior Art

It has heretofore been proposed in the patent to Flynn, U.S. Pat. No. 3,497,308 to collect noxious components from a stack and burn the same. The structure there shown is not suitable for the purposes of the present invention because of the lack of suitability of the intended mode of collection of the combustibles for loading, storing and dispensing facilities and the lack of safety features to avoid flash back.

It has also been proposed in the patent to Husa, et al., U.S. Pat. No. 3,783,911 to collect hydrocarbon vapors before they are dispersed in the atmosphere, monitor the vapors to determine when they are near or in the combustible range and add propane, also combustible, to remove the danger of explosion or fire, storing the material in a holding tank and then periodically burning it. The structure shown by reason of its introduction of flammable gas such as propane, is not free from explosion hazards, including flash back.

Various burners have heretofore been employed for burning gaseous combustibles from a source under pressure but these are usually intended for continuous burning at selected firing levels. Note the patents to Barnes, U.S. Pat. No. 3,194,215 and Verner, U.S. Pat. No. 2,761,496 which are intended for very large quantities of gas containing combustibles and are unsuited for handling the quantities of vapor disposed of with the system of the present invention.

None of the structures heretofore proposed is as effective as that herein disclosed for hydrocarbon vapor elimination, with freedom from flash back and with ease of access for inspection and maintenance of the combustion chamber components.

SUMMARY OF THE INVENTION

In accordance with the present invention apparatus is provided for use at automobile and truck tank filling stations, and other storage and dispensing facilities preferably utilizing the pressure of the flammable liquid being dispensed for collecting combustible vapors such as those of gasoline, fuel oil, jet fuel and other cobustible liquids, separating the combustible vapor and burning it. The structure for smokeless burning is adapted for disposal of vapors over a wide fluctuation of firing rates and compositions, and has provisions at the burners and in advance thereof to avoid flash back and protect the apparatus from excessive temperatures.

It is the principal object of the invention to provide combustible vapor collection and disposal apparatus for the vapors from volatile combustible liquid dispensing apparatus which utilizes the pressure of the liquid being dispensed.

It is a further object of the invention to provide simple but effective apparatus of the character aforesaid which has reliable provisions for smooth and even combustion.

It is a further object of the invention to provide apparatus of the character aforesaid which optionally may include provisions for noise reduction and for weatherproofing.

Other objects and advantageous features of the invention will be apparent from the description and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The nature and characteristic features of the invention will be more readily understood from the following description taken in connection with the accompanying drawings forming part hereof, in which:

FIG. 1 is a diagrammatic view of one embodiment of vapor handling equipment in accordance with the invention and which is particularly suited for automobile and truck fuel tank filling stations;

FIG. 2 is a diagrammatic view of control apparatus for the vapor handling equipment in accordance with the invention.

FIG. 3 is a diagrammatic view of another embodiment of vapor handling equipment in accordance with the invention and which is particularly suited for tank truck filling stations and other storage and dispensing facilities;

FIG. 4 is a vertical central sectional view of one form of vapor burning unit employed with the present invention;

FIG. 5 is a vertical sectional view taken approximately on the line 5--5 of FIG. 3;

FIG. 6 is a vertical sectional view taken approximately on the line 6--6 of FIG. 3;

FIG. 7 is a view similar to FIG. 3 showing a modified form of a vapor burning unit employed with the present invention;

FIG. 8 is a fragmentary sectional view of a filling nozzle and vapor removing structure in accordance with the invention; and

FIG. 9 is a transverse sectional view, enlarged, of one of the vapor burner pipes.

It should, of course, be understood that the description and drawings herein are illustrative merely and that various modifications and changes can be made in the structure disclosed without departing from the spirit of the invention.

Like numerals refer to like parts throughout the several views.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now more particularly to FIG. 1 of the drawings an automobile or truck fuel tank loading station for a motor vehicle MV is shown to which volatile liquid combustible hydrocarbon under pressure is pumped by a motor operated pump LP through a supply pipe P (see FIG. 8) and filling nozzle N carried within a vapor take off and return pipe R within which the pipe P and nozzle N can be carried. The hydrocarbon can be gasoline, volatile oil, jet fuel or the like and is supplied under a positive pressure for delivery through the nozzle N into the fuel tank (not shown) of the motor vehicle MV.

The vapor take off and return pipe R is connected by a pipe 10 to a fluid connection 11 for return of any of the vapor which condenses to an underground liquid separation and storage tank 12 from which the motor operated pump LP is supplied through a supply pipe 13.

The fluid connection 11 is connected by a pipe 15 through a flame arrester grid 16 to a closed housing 18 containing a body 19 of non-flammable liquid such as water, providing a liquid seal, the pipe 15 extending below the level of the body 19 of liquid in the housing 18. A liquid level controller 20 for a supply control valve 21 can be provided to maintain the level in the housing 18 from a source of liquid 22.

A low level water probe LC1 is provided in housing 18 at a predetermined level to provide for control of the system if the water level is at or below a level at which operation would be unsafe.

The housing 18 has connected in series therewith a vapor take-off pipe 23 connected to the housing 18 above the level of the seal liquid therein, through a flame arrester grid 24 extending into a second liquid housing 18a below the level of the body 19a of liquid therein.

A liquid level controller 20a is provided for the housing 18a for a supply control valve 21a connected to the source of liquid 22.

A low level water probe LC2 similar to LC1 is provided in housing 18a to indicate an unsafe water level and is connected in series with the probe LC1.

The housing 18a has connected in series therewith a vapor take-off pipe 28 connected to the housing 18a above the level of the body 19a of liquid in the housing 18a.

The pipe 28 is connected through a flame arrester grid 29 to a vapor disposal unit DU for disposal by burning.

Referring now more particularly to FIG. 3 of the drawings a tank farm is illustrated having storage tanks 40 connected at their lower portions by pipes 41 for liquid distribution therebetween and with a liquid delivery pipe 42 having a motor driven pump LP therein for delivery of liquid through a delivery pipe P to a tank truck TT or the like to be filled.

The tanks 40 may be utilized for storage of volatile liquid combustible hydrocarbons.

The tank truck TT preferably has a vapor return pipe 43 connected thereto through a check valve 44 to a fluid connection 11.

The structure connected to the fluid connection 11 can be similar to that previously described with respect to FIG 1.

Referring now more particularly to FIGS. 4, 5 and 6, one preferred embodiment of a vapor disposal unit DU is there shown in detail.

The vapor disposal unit DU there shown includes an outer cylindrical metallic casing 50 with a liner 51 of ceramic refractory material secured thereto to resist combustion temperatures.

The casing 50 and liner 51 can be supported by legs 52. While the casing 50 and liner 51 are shown as circular in horizontal cross section, any other desired horizontal cross section can be employed.

The casing 50 has mounted therein at the lower end thereof a refractory burner ring 53 with spaced horizontal openings 54 for main gas burners M1, M2, M3 and M4 illustrated in opposed pairs with gas supply pipes 56. The refractory burner ring 53 is also provided with spaced horizontal openings 57 for the reception of pilot burners P1 and P2 preferably utilizing gas from gas supply lines 59.

The burners M1, M2, M3, M4 and P1 and P2 are preferably shrouded as at 60 and 61 and with their air inlets facing downwardly for burner protection, and for noise reduction.

Immediately below the burner ring 53, an air damper housing 62 is provided terminating above the ground for access of air therebelow. The damper housing 62 at the bottom thereof is provided with a plurality of parallel pivotally removably mounted horizontally disposed damper plates 63, whose positions are controlled in any desired manner for controlling the intake of air induced within the vapor disposal unit DU to support combustion, but as illustrated are controlled by a damper motor DM.

Within the interior of the damper housing 62 an acoustical lining 64 can be provided for sound absorption to reduce audible exterior noise.

The pipe 28, as illustrated in FIGS. 4, 5 and 6, extends horizontally with an upturned vertical end which terminates at a vapor burner head 65. The head 65 has a central cylindrical portion 66 with a plurality of radially outwardly extending tubes 67 each with a slit 68 along the side near the top thereof for delivery of vapor therethrough in a swirling combustion pattern. The slits 68 are of a width of the order of ten thousandths of an inch for quenching action and to prevent flash back through the slits 68.

The housing 50 as first described can serve as a combustion chamber but for some installations a cylindrical metal insert 70 open at the bottom can be employed spaced inwardly from the housing 50, to provide with a refractory liner ring 69 a passageway 71 closed at the top and with restricted access at the bottom.

The combustion chamber insert 70 is supported by spaced arms 71 below a frustoconical closure wall 72 on top of which vertical legs 73 are provided supporting a conical roof 74. The roof 74 can have a protective ceramic refractory lining 75 secured thereto.

The combustion chamber insert 70 and its cover are employed where protection from snow and wet weather is desired.

Referring now to FIG. 7, the structure of the unit DU there shown is similar to that previously described but employs oil burners M1A, M2A, M3A, and M4A in place of the gas burners previously described.

A thermocouple 78 is provided extending into the interior of the units DU for purposes of high temperature shut off control responsive to the temperature of combustion and is connected to a relay HTR.

Referring now more particularly to FIG. 2 the control circuit for safe positive control of liquid pumping is illustrated. To start the pump LP a signal is initiated in line 100 which is connected to low water level probe LC1 in housing 18, which signal passes to low water level probe LC2 if the water level is above the probe LC1 but stops the signal if the water level is at or below LC1. The signal from LC1 can pass through LC2 if the water level in housing 18a is also above the probe and is effective through line 101 to cause the ignition of pilots P1 and P2 and through lines 102 and 103 closes relays PR1 and PR2 to permit the signal from 101 to pass therethrough to line 104.

Line 104 is connected to normally closed relays BR1 and BR2 which by line 105 are connected through normally closed relays BR3 and BR4 by line 106 to the liquid pump LP permitting pump LP to operate for liquid loading.

The pipe 28 downstream of flame arrester 29 has a specific gravity measuring device SG of well known type connected thereto to sample the specific gravity of the flow of air and vapor from housing 18a . The device SG is connected by line 110 to a pneumatic multiplier PM and provides a signal thereto when the specific gravity of the air vapor mixture is above a predetermined level indicating a combustible content and varying in accordance with the combustible content. The multiplier PM is connected by line 111 to an air damper motor DM which controls the position of the air damper plates 63 and the flow of air into unit DU. A flow cell F is also connected to the pipe 28 to measure the flow of air and vapor in pipe 28 and is connected to a square root extractor .sqroot. and to multiplier PM by line 112 to provide a signal corresponding to the flow. A signal transmitting temperature probe T is inserted into the interior of the unit DU which measures the temperature linearly and is connected by a line 114 to multiplier PM to provide a signal related to the temperature.

The signals from temperature probe T, specific gravity measuring device SG, and flow measuring device F operate through the multiplier PM to provide a control signal to motor DM to position the plates 63 for optimium air flow depending on the flow, temperature and vapor composition of the mixture to be burned.

The line 111 has two pressure switches PSW1 and PSW2 connected therein which are activated at predetermined pressures at different levels determined by the number of burners M1, M2 and M3, M4 desired for the combustible content to be handled.

The switch PSW1 is connected by line 115 to the burners M1 and M2 or M1A and M2A and controls the turning on and off of these burners.

The burners M1 and M2, M1A and M2A are connected by lines 116 and 117 to relays MR1 and MR2 to cause the relays to close when the burners are activated and a signal from line 104 to pass therethrough. The line 115 is also connected to relays BR1 and BR2 and the signal therethrough causes these relays to open when burners M1 and M2, M1A and M2A are activated.

The switch PSW2 is connected by lines 120 and 121 to burners M3, M4, M3A and M4A with a signal therefrom causing the burners to be turned on and off. The lines 120 and 121 are also connected to normally closed relays BR3 and BR4 with a signal therefrom causing the relays to open.

The burners M3, M4, M3A and M4A are connected by lines 122 and 123 to normally open relays MR3 and MR4 with a signal from the burners M3, M4 and M3A and M4A causing the relays to close and permit a signal from line 105 to pass through the relays MR3 and MR4 to the liquid pump LP for starting.

The high temperature relay HTR is connected by a line 130 to a relay TR connected to line 106 which is normally closed but will be opened by temperatures above a predetermined high level in the units DU, thereby shutting off the pump LP.

The mode of operation will now be pointed out.

Combustible vapors displaced preferably by liquid delivered through a pipe P to a motor vehicle MV are returned through a pipe R as shown in FIG. 1 to the fluid connection 11 or by liquid delivered through a pipe 42 are returned through a pipe 43 to the fluid connection 11.

The vapors from the fluid connection 11 are delivered through the flame arrester 16, the flame trap provided by the liquid in the housing 18, the flame arrester 24, the flame trap provided by the liquid in the housing 18a, the flame arrester 29 and through the pipe 28 to the burner head 65 of the unit DU.

In the unit DU as illustrated in FIGS. 4, 5 and 6 the vapor is delivered through the slits 68 with a whirling action imparted thereto for combustion with the burning gas from the gas burners M1A, M2A, M3A, M4A.

Air for combustion is induced through the bottom space below the housing 62 by the position of plates 63 which are controlled by the combined effect of the temperature probe T, specific gravity devices SG and flow measuring device F through the multiplier PM operating the motor DM as called for.

It may be noted that there can be a wide fluctuation both in flow rate and in the composition of the vapor delivered to the disposal unit DU. The composition can be in a range from approximately 50% hydrocarbon and 50% air to about zero hydrocarbon and 100% air. These wide variations in composition are accompanied by a wide range of heat release. Air in precise quantities is required for smokeless combustion with additional air required for dilution to cool the combustion zone and prevent overheating of the disposal unit DU, and this is effected with induced draft by use of motor DM and plates 63.

When the quantity of combustible vapor is low then heat must be added to insure a hot oxidation zone so that none of the vapor will escape unburned and cause atmosphere pollution. The main burners M1, M2, M3, M4 or M1A, M2A, M3A, M4A are utilized for this purpose, one pair or no burners being required with high combustible content of the vapor delivered to the unit DU and additional burners M3, M4, or M3A, M4A being brought into or taken out of action as required.

The pilot burners P1, P2 are continuously available for initiating combustion of the fuel supplied by the main burners M1, M2, M3, M4 or M1A, M2A, M3A, M4A as well as vapors supplied by the vapor burner head 65.

The pump LP cannot be operated unless a signal passes through the low level probes LC1 and LC2, through the relays BR1, BR2 or MR1, MR2 and relays BR3, BR4 or MR3, MR4 whose operation is dependent upon the signal from the multiplier PM through pressure switches PSW1 and PSW2 activating the burners M1, M2, M3 M4 or M1A, M2A, M3A and M4A. Should any of the burners fail to ignite, the system will be shut down and the pump LP will not operate with one or more open relays in the circuit shown in FIG. 2 between lines 100 and 106.

Should the operating temperatures in the units DU be excessive the relay TR will open and the pump LP will be stopped.

It will thus be seen that apparatus has been provided with which the objects of the invention are attained.

Claims

I claim:

1. Apparatus for collection and disposal by combustion of combustible vapor from a tank displaced by liquid introduction loading which comprises

a pump for delivery of liquid to the tank,

a combustible vapor collector pipe associated with the tank for collection of vapors displaced therefrom under pressure by liquid introduced into the tank by the pump,

a disposal unit for combustion of said vapor comprising a combustion chamber,

a connection from said vapor collector pipe to said combustion chamber for delivery of vapor to said combustion chamber for combustion and having a plurality of flame arresters interposed therein,

a vapor burner supplying said vapor to said combustion chamber for combustion therein,

burner means for burning fuel in said combustion chamber to provide an oxidizing zone therein aiding the combustion of said vapor from said vapor burner,

air supply means for admitting air to said combustion chamber for combustion of said vapor and of said fuel from said burner means, and

means responsive to a condition in said apparatus for controlling said pump.

2. Apparatus as defined in claim 1 in which

said last mentioned means comprises a member responsive to the temperature in said combustion chamber for shutting off said pump when said temperature exceeds a predetermined limit.

3. Apparatus as defined in claim 1 in which

said last mentioned means comprises a member responsive to the operation of said burner means for preventing operation of said pump when said burner means does not operate.

4. Apparatus as defined in claim 1 in which

pilot burner means is provided for said combustion chamber, and

said last mentioned means comprises a control member for preventing operation of said pump when said pilot burner means does not operate.

5. Apparatus as defined in claim 1 in which

said flame arresters comprise a housing containing a predetermined quantity of non-flammable liquid providing a flame trap, and

said last mentioned means comprises a control member for preventing operation of said pump when said predetermined quantity of liquid is not present in said housing.

6. Apparatus as defined in claim 1 in which

said burner means comprises a plurality of selectively operated burners, and

means is provided responsive to the combustible condition of the vapor in said connection for determining the selective operation of said burners.

7. Apparatus as defined in claim 1 in which

said burner means comprises a plurality of selectively operated burners, and

means is provided responsive to the flow of said vapor in said connection for determining the selective operation of said burners.

8. Apparatus as defined in claim 1 in which

said burner means comprises a plurality of selectively operated burners, and

means is provided responsive to the temperature in said combustion chamber for determining the selective operation of said burners.

9. Apparatus as defined in claim 1 in which

said air supply means comprises an adjustable damper, and

damper control motor means is provided for adjustment of said damper.

10. Apparatus for collection and disposal by combustion of combustible vapor from a tank displaced by liquid introduction loading which comprises

a pump for delivery of liquid to the tank,

a combustible vapor collector pipe associated with the tank for collection of vapors displaced therefrom under pressure by liquid introduced into the tank by the pump,

a disposal unit for combustion of said vapor comprising a combustion chamber,

a connection from said vapor collector pipe to said combustion chamber for delivery of vapor to said combustion chamber for combustion and having a plurality of flame arresters interposed therein,

a vapor burner supplying said vapor to said combustion chamber for combustion therein,

burner means for burning fuel in said combustion chamber to provide an oxidizing zone therein aiding the combustion of said vapor from said vapor burner,

air supply means for admitting air to said combustion chamber for combustion of said vapor and of said fuel from said burner means,

said air supply means comprising an adjustable damper,

motor means for adjustment of said damper, and

control means for said motor means responsive to the condition of said vapor.

11. Apparatus as defined in claim 10 in which

said control means comprises a member responsive to the flow of vapor in said connection.

12. Apparatus as defined in claim 10 in which

said control means comprises a member responsive to the specific gravity of the vapor in said connection.

13. Apparatus as defined in claim 10 in which

said control means comprises a member responsive to the temperature in said combustion chamber.

14. Apparatus as defined in claim 10 in which

said air supply means comprises a plurality of damper plates pivotally mounted below said vapor burner positioned by a motor.

15. Apparatus as defined in claim 10 in which

said vapor burner means comprises tubular members with flash back preventing slits delivering vapor for combustion.

16. Apparatus as defined in claim 10 in which

said flame arresters additionally include a screen grid.

17. Apparatus as defined in claim 10 in which

said burner means comprises a gas burner.

18. Apparatus as defined in claim 10 in which

said burner means comprises an oil burner.

19. Apparatus as defined in claim 10 in which

said vertical casing has a weather protective cover mounted thereon and disposed over the upper end thereof.

20. Apparatus as defined in claim 19 in which

said cover has a combustion chamber liner extending downwardly therefrom in inwardly spaced relation to said vertical casing.

21. Apparatus as defined in claim 10 in which

said vertical casing has a refractory ring in which said burner means is mounted with burner members in opposed relation.

22. Apparatus as defined in claim 21 in which

said air supply means comprises a damper housing mounted below said ring and said vapor burner with a plurality of damper plates pivotally mounted below said vapor burner.

23. Apparatus as defined in claim 21 in which

said air supply means comprises a damper housing mounted below said ring, and

said damper housing has a sound deadening lining.