US2450824A - Liquefied gas dispensing apparatus - Google Patents

Description

0d- 5 1948- w. c. BUTTNER LIQUEFIED GAS DISPENSING APPARATUS Filed June 25, 1941 Patented Oct. 5, 1948 Es PATENT OFFICE LIQUEFIED GAS DISPENSING APPARATUS William C. Buttner, Winnetka, Ill., asslgnor to The Bastian-Blessing Co., Chicago, Ill., a corporation of Illinois Application June 25, 1941, Serial No. 399,715 15 claims. (01; scf-1) The present invention relates generally to liquefied petroleum gas dispensing systems and more particularly tothe type of installation in which the storage tank is buried underground where heat present in the ground assists in vaporizing the gas. v

The present invention is a continuation in part of application Serial No. 359,002, filed by me September 30, 1940, for Gas dispensing apparatus and now abandoned.

In many respects, the apparatus employed to represent the present invention, is similar to that shown in the William C. Buttner application Serial No. 271,089 filed May 1, 1939, reference to which is hereby made. To the extent that a similarity of parts exists between the embodiments of the two inventions, the disclosure of the above application is incorporated herein for a better understanding of the present invention.

The petroleum product employed in the systems with which the present invention is concerned, is preferably of the paramn series, such as butane or propane, or both, and this fuel is stored in the form of a liquefied gas.l

In order to use the fuel in an appliance such as a gas stove, the liquefied gas is vaporized and vaporizaton may be accomplished in one of two ways which are essentially similar.

One of these ways is the so-called batch system, in which vaporizaton is carried on in the tank and the vaporized fuel is progressively withdrawn for service fromthe top of the tank. The second, or so-called flash system; the liqueed gas is withdrawn from the bottom of the tank and conducted through a pressure regulator where a sudden reduction in pressure causes the fuel to flash into gas.

In the batch system, the heat absorption due to vaporizaton is largely confined to the tank, whereas in the flash system, the refrigeration effect is concentrated or localized with respect to the region of the pressure regulator. In the former case, the fuel is mostly gas when it reaches the reduction regulator and comparatively little refrigeration is involved outside of the tank except Y that involved in revaporization, whereas, with the flash system, a great deal of heat absorption is -required in a small space.

, 2 y transfer of heat from the earth to the regulator. In brief, with such an installation, the regulator creates a secondary frost line and a condition which, like a frosted coil in a refrigerator, defeats the purpose of bringing the regulator into contact with the earth and hinders the needed transfer of heat.

Although the present invention will improve vaporization for both systems, it is illustrated in y its preferred form in combination with the flash system where the conditions are found to be more severe. However, certain relations are discussed which will enable one skilled in the art to adapt the invention to batch systems. Consequently, it is one of the objects of the present invention to improve heat transfer conditions in the vaporizaton phase of a liquefied petroleum gas system.

A further object of the invention is to provide a vaporizing system for liquefied petroleum gas dispensers wherein the vaporizaton regulator as well as the service conduit, is supplied with heat drawn from a surface area of earth greatly in excess of the surface area withinV which the heat lis absorbed. It is another object of the invention to locate a vaporizaton regulator in the earth, below the frost line, and remove it from contact with the earth by providing an air space so disposed that moisture condensation collecting upon the regulator will run o into the ground remote from the air space and further humidity I acquired from the ground assists, along with convection in transferring ground heat to the regulator.

Moreover, it is one of the objects of the invention to have the vaporizaton regulator in heat transfer contact with the wall of a container having an anti-freezing iiuid therein exposed to ground heat, which prevents excessive frosting of the regulator under heavy or sudden flows of gas in the service conduit and serves to defrost the regulator rapidly at periods of time when the ow of fluid is less active.

More specifically, it is yone of the objects of the invention to locate the vaporizaton regulator in heat exchange contact with the wall of the storage tank for the purpose stated so that the gas inside of the tank can condense upon the wail of the tank proximate to the regulator to discharge heat thereto and will then drip back into the liquid to absorb more heat which has been accumulated from the ground by the body of liquid through the wall of the tank.

It is also a purpose of the invention to minimize the amount of' service conduit disposed outside the tank as regards that portion of service conduit disposed between the vaporization regulator and the point where it connects with a coil disposed in th'e storage tank.

These being among the objects of the present invention, other objects will become apparent from the drawing, the description relating thereto and the appended claims.

In the drawing: 4

Fig. 1 is a side elevation partly in section illustrating the invention in its preferred embodiment.

Fig. 2 is a fragmentary enlarged section taken upon the line 2-2 in Fig. 1.

Fig. 3 is an enlarged section taken upon line 3 3 of Fig. 2.

As has already been mentioned, the invention is illustrated in connection with the flash system in which liquefied gas is first withdrawn from the storage tank having pressures normally experienced with liquefied petroleum gas; is passed through a first vaporizing regulator which reduces the pressure to a first stage pressure range as low as practical and then is conducted through a second pressure regulator which reduces the gas pressure to the service pressure of 6 ounces per square inch.

cap spring 84 is employed to stabilize the action of the valve and diaphragm.

The back cap 4I is attened at its lowest extremity to contact the top of the container II in heat exchange relationship.

A platform 43, which, if made of metal, may be welded to the tank I I as at 44, has an aperture therein to receive the back cap 4l and permit that portion of the regulator to contact the tank in heat exchange relationship. The apertured platform serves to support th'e regulator against damage in transit and also serves as a heat conveying n on the tank which radiates conducted heat after the tank is installed.

Vaporized gas is conducted from the regulator 35 by tubing 46 connected to the outlet side thereof, and the tubing 46 leads directly back Into the tank as at 41 in sealed communication with a coil 48 which is disposed in the tank with a major portion of its length submerged in the liquefied gas 3|.

The regulator 35, the valve 34 and connections 36 and 46 are covered by a box or housing 5I which rests on top of the tank II and has a In the drawing, a storage tank is indicated at I I, as buried in the earth I2 below the frost line I3 normally expected in the region where the installation is made. The tank is filled and vented through a standpipe I4 which carries a slip tube gauge I5 accessible at the cap I6 and a vent or vapor return pipe I1 provided with a splash` bolts 29. The liquefied gas 3| is withdrawn from the bottom of the tank by a dip tube 32 provided with an excess flow check valve 33 therein to prevent escape of the fuel from the tank in the event there is a break in the system outside of the'tank. A manually controlled shutoff safety valve is connected to an automatic pressure regulator or pressure reduction valve 35 by nipples 36 and a union 31.

. The regulator 35 comprises a body portion 42 having an inlet 18 and outlet 19 therein with the inlet leading through a bridge 88 to a port 8i and the outlet leading from a valve chamber 82. The chamber is closed by a diaphragm 83 held in place by a bonnet 84 as flexed inwardly by means of a compression spring 85 mounted between a diaphragm plate 86 upon the diaphragm and an adjusting screw 81 threaded into the bonnet to establish a predetermined pressure upon a screw. A locknut 88 prevents inadvertent loosening of the screw 81,

The diaphragm plate has a threaded opening therein to fasten a yoke 89 upon the diaphragm whichI yoke straddles the bridge 80 and carries on the bottom-end thereof a valve member 90 supporting a seat 9i in cooperation with the port 3|.

A back cap 4I extending downwardly from the valve body forms the bottom wall of the chamber and is in heat exchange contact not ,only with the body portion 42 but also with the valve member 90 where a cylindrical boss 82 guides a center piece 93 upon the valve member. A back hinged or removable cover 52. A pipe 53 lled with insulating material 54 connects the housingl 5I with the concrete box 26 through an opening in the concrete box, and has disposed therein a valve shaft 55 operating the hand valve 34 as controlled by a handle 56 disposed in the box 26.

Other than for the slight infiltration that might take place through the heat insulating material 54, the stand-pipe I4 and regulator 35 are air and heat sealed from each other as by the filling of earth between them. With this construction. the regulator 35 and connections conducting the liquefied gas and vaporized gas outside of the tank areA sealed from access of freely moving atmosphere by a layer of removable earth filling, yet the valve 34 in the housing 5I can be controlled without need for the removal of the earth filling which seals the housing 5I from the atmosphere.

The outlet end of the coil 48, indicated at 51 is preferably spaced from the inlet 41 of the coil as separatedby earth, and, although shown as disposed at the center of the head 58 of the tank, may be located at any point convenient upon the tank.

A service main 6| leads from the outlet 51 into the cellar 62 or space below the first floor 63 of a dwelling. 'I'he main 6I when necessary, passes through the foundation 64 at an opening such as that indicated at 65 where it is sealed against the passage of moisture by an annular member 66 preferably made of a workable dense material which can be packed in place.

From the main 6I, which preferably slopes towards the tank, the gas is carried upwardly by a riser 61 which connects with a finned vaporizer 66 of a type such as that disclosed in the Patent #1,752,166 issued to R. G. Ford, March 25, 1930.

At the outlet of the vaporizer 68, a hand operated shutoff valve 1I is mounted on a bracket 12 which supports a shelf 13 on which is disposed a pressure reduction regulator 14 connected to the hand valve 1I by a tube 15. The pressure regulator 14 reduces the vaporized gas to the service pressure of 6 ounces per square inch and the gas is then delivered to an appliance (not shown) by the appliance conduit 16.

In the present invention the vent tube 18 for the regulator 14 is inclined downwardly throughout its length to drain from the regulator any moisture collecting therein. In the particular arrangement shown, the regulator 14 is'disposed above the outlet 18 of the vent tube and also above the space into which the outlet opens whether it be a glycerin cup such as shown in the co-pending Buttner application, Serial No.

, back into the coll for the revaporization men- 27l,089, another source of anti-freeze fluid, or a confined spaced where humidity is kept at a minimum. f

In operation, once the tank \|l has been filled to the permitted level,.in the well known manner, vthe heat present in the earth becomes effective to raise the temperature of the liquefied gas to-its boiling 'point Vby which suiilcient vapor is generated to establish a pressure head in the tank.l

The valve 34 is opened and liquefied gas will be forced through the regulator by the head pressure in the tank and the pressure of the withdrawn gas is reduced by the' regulator to a low pressure. Y

With this reduction in' pressure, the boiling point of the liquefied gas is-'suddenly lowered and the liquefied gas ashes into vapor to the extent that vaporization is supported by heat units available in the conducting parts that are necessary to sustain the temperature of the vapor above the condensation point at that pressure.'

Thus, the regulator 35 and conduit 46 beyond the regulator becomes a refrigerated agent requiring a large quantity of heat to sustain the vapor phase of the fuel gas. The `area of these parts is relatively small and therefore the heat tioed/ providedV the neat of the ground around the service main is insufficient-mathe purpose.

The iinned vaporizer 68 assists in r'vaporizing when disposed where a Warm fluid may contact it. Consequently, by maintaining the fuel in the service conduit vaporized by the means already described, the further reduction in pressure taking place in the second regulator further lowers the point of vaporization and assures a full flow of dry gas to the appliance.

In view of the fact that the second regulator breathes, the pressure control side of the diaphragm therein is vented to the atmosphere by thel tube 19. The breathing action has `a tendabsorption exerted at these points is very high.

However, with the tank in contact with the relatively warm earth over a large area and the contact between the regulator and the tank, this provides for direct heat conduction of large quantities of heat to the regulator. Furthermore,

the housing 5| being in contact with the earth A over a large area and the encompassed air which circulates convectively between the walls of the housing and the surface of the regulator, also supplies heat to relieve the refrigeration conditions.

The contact between the regulator and the tank renders the heat in thewall of the tank available to the regulator at the back cap to which any liquid unvaporized gravitates. Transfer of heat from the tank to the regulator in this area creates a cold zone at the top of tank onto which vaporized gas in the tank condenses to discharge heat to the cold zone and then drops back into the liquid to be heated and vaporized again, conduction and convection, both, taking place inside the tank for the accomplishment of this purpose. l

With regard to the heat transfer in the housing 5I, humidity in the air in the housing 5I condenses o n the regulator to supply it with heat and the condensate runs onto the warm tank where it is evaporated again and again to repeat the convective and condensation-evaporation cycle. In-these ways, the rst stage regulator is ableto effect vaporization to the maximum degree and maintains same for the normal flow or less than normal flow, experienced in the use of the gas. V

Under the extra heavy iiow of gas, the coil 48 in the tank assists in the initial vaporization, and where extreme outside cold might induce condensation in the service line, revaporization is had in the coil through the relatively abundant supply of heat available in the liqueiied gas.

In this connection, with the tube 6I slanting towards the tank Il, any condensation sufllcient` ency to cause the collection of moisture in the tube and if it were possible for the moisture to reach the diaphragm compartment, it might freeze there and upset the functioning ofthe system by locking theA diaphragm and the valve controlled thereby. This would constitute a dangerous condition.

The vent tube 19 in the present invention is l'inclined downwardly so that moisture at all times In this way, the present invention provides animproved liquefied gas dispensing apparatus and although in some respects it is diiiicult to account fully for the improved results which are obtained by the method and apparatus of the present invention, it is to be understood that any attempt to analyze the theories which are believed to be responsible for the improved and new results, is to be construed not as defining a mode of operation, but merely as a possible explanation of certain physical phenomena which have been observed.

Consequently, although a certain preferred embodiment of the present invention has been shown and described herein, a way has also been suggested by which the present invention may be utilized in the so-called batch systems and spirit or lsubstance of the invention, the scope of which is commensurate with the appended claims.

What is claimed is: v

1. In a liquefied petroleum gas dispensing system having a storage tank buried below the frost line, a service conduit leading from the tank to an appliance, a vpressure reducingvalve in said conduit in contact with the tank, vault means providing an air space around the regulator sealed from the atmosphere by a wall of earth, means for lling the tank remote from the regulator, and a coil in said conduit between the regulator and appliance and disposed inside the tank.

2. In a liquefied petroleum gas dispensing system having a storage tank buried underground in heat exchanging relation with the surrounding earth and adapted to be iilled from above the ground level, a delivery conduit communicating with the tank and extending to a point of use; a pressure reducing regulator in said delivery conduit arranged with the back cap thereof in contact with the tank to absorb some heat there- 7 from; and filler material between the regulator and the ground level to prevent atmospheric air from freely circulating in contact with and to permit access to the regulator only when the filler material is removed.

3. In a liquefied petroleum gas dispensing system having a storage tank buried underground in heat exchanging relation with the surrounding earth and adapted to be filled from above the ground level, a service conduit communicating with the tank at a point spaced from the point of illing by earth fill and extending to a point of use, a pressure reducing regulator in said conduit arranged in contact with the tank to absorb heat therefrom, means supporting earth around the regulator to provide a space containing a fluid between the regulator and the earth, and filler material between said means and the ground level to prevent atmospheric air from freely circulating in contact to the regulator.

4. In a liquefied petroleum gas dispensing system having a subterranean storage tank receiving heat from the earth and adapted to be filled from above the groundl a. service conduit leading from the tank to a point of use, a pressure reducing regulator in said conduit disposed in contact with the tank, a housing around said regulator providing a space containing convectively circulated fluid between the regulator and the adiacent earth, and ller material between said housing and the ground level to prevent atmospheric air from freely circulating in contact with and to permit access to the regulator only when the filler material is removed.

5. In a liquefied petroleum gas system having a subterranean storage tank receiving heat from the ground and adapted to be filled from above the ground, a -delivery conduit communicating with the tank and extending to a poinlt of use, said conduit comprising a dip tube whose inlet is near the bottom of the tank for removing liquid from the tank, a pressure reducing regulator in contact with lthe tank and receiving liquid from said tube, and means including a iiller material between the regulator and the ground level to prevent atmospheric air from circulating in contact with the regulator, said regulator being accessible when said means is removed.

6. In a liqueed petroleum gas system having a subterranean storage tank receiving heat from.

the ground, a delivery conduit communicating with tbe Tank and extending to a point of use, and comprising a dip tube for withdrawing fuel from the tank in its liquid phase, a pressure reducing regulator in contact with the tank, and a second pressure regulator reducing the gas to a usable pressure at said point of use.

'7. In a liquefied petroleum gas system having a subterranean storage tank receiving heat from the ground, a delivery conduit communicating with the tank and extending to a point of use, said conduit comprising a dip tube opening near the bottom of the tank for removing liquid from the tank, a pressurereducing regulator in contact with the tank, a coil disposed in 'heeft exchange relationship with the content-s of said tank and a second pressure regulator reducing the gas to a usable pressure at said point of use.

8. In a, liquefled petroleum gas system having a subterranean tank receiving heat from the ground, a service conduit for vaporizing a liquefied petroleum gas comprising a dip tube opening near the bottom of the tank for withdrawing liquid from a body of liquid under pressure, a pressure reducing regulator in contact with said tank, a

second pressure regulator reducing the gas to a usable pressure at a point of use, a cover enclosing the first regulator to prevent atmospheric air from circulating in contact with the first regulator, said ilrst regulator being accessible when the coveris removed.

9. In a liquefied petroleum gas system having a subterranean tank receiving heat from the ground, a service conduit for vaporizing a liquid petroleum gas comprising a tube for withdrawing liquid from a body of liquid under pressure at a point near the bottom of the tank, a pressure reducing regulator in contact with the tank, a vaporizer disposed in heat exchange relationship with the contents of said tank, a second pressure regulator reducing the gas to a usable pressure at a point of use; means including a ller material between the I*first regulator and the ground level to prevent atmospheric air from circulating in contact with the first regulator, said first regulator being accessible when said means is removed.

l0. In a liquefied petroleum gas system having a subterranean tank receiving heat from the ground, a lservice conduit for vaporizing a liquefied petroleum gas comprising a tube opening near the bottom of the tank for withdrawing liquid from a body of liquid fuel under pressure, a pressure reducing regulator in contact with said tank. a second pressure regulator reducing the gas to a usable pressure at a point of use, a housing over the first regulator providing a space between the first regulator and the earth and filler material between the housing and the ground level to prevent atmospheric air circulating in contact with the first regulator being accessible when the filler material is removed.

11. In a liqueiled petroleum gas system having a subterranean tank receiving heat from the ground, a service conduit for vaporizing a liquefied petroleum gas comprising means for edu-ating liquid from a body of liquid fuel under pressure, a

pressure reducing regulator in heat conducting.

contact with said tank, a vaporizer disposed in heat exchange relationship with the contents of said tank, a second pressure regulator reducing the gas to a usable pressure at a point of use; a housing over the rst regulator providing a space between the first regulator and the earth, and filler material between the housing and the ground level to prevent atmospheric air circulating in contact with the housing, said first regulator being accessible when the filler material is removed.

12. In a liquefied petroleum gas dispensing system having a tank buried underground in heat exchange relationship with the surrounding earth, a conduit for vaporizinga liquefied petro-I leum gas comprising an inlet receiving fuel under pressure, a pressure reducing regulator having a body portion and a protruding portion thereon in heat receiving contact with the tank, a platform associated with the tank and having a hole therein for receiving said protuberance, said platform being disposed proximate the body vportion of the regulator.

mospheric air, means for filling the tank remote from the pressure reducing device.

sus

1'4. In a liuueiied petroleum ses vdispensing system, a container having a vaporizable liquid therein. a pressure reducing valve having a body with a chamber therein extending into the low-4 est porti-on oi the body. a member upon the container .to locate said lowest portion in contact with a wall of the container, means for conducting fuel Ito the valve under pressure, and means for conduit communicating with the tank and extending to a. point of use; a pressure reducing regulator in said delivery conduit arranged in direct contact with the tank to absorb some heat therefrom: and earth` illl between the regulator and the s i0 freely circulating in contact with and .to permit access to the regulator only when the nller material is removed.

v WILLIAM C. BUTINER.

americas c rrnn The iollowini'r references are of record in the ille of this patent:

UNITED STATES PATENTS Number YName Date 2,155,340 Stroud Apr. 18, 1939 2,251,796 Howard Aug. 5. 1941 2,357,777 AWhite Sept. 5. 1944 15 y2,400,569 Norway May 21, 1946 OTHER REFERENCES Individual consumer Buxx systems" by E. L Mills. pases 52 to 55 and 'I0 o! March 1937, issue ground level to ,prevent atmospheric air from n of Gas. See particularlyFlg. 2.

Images