Vaporizing apparatus

Sept. 24, 1946.

2,408,084

J. W. MARTIN

VAPORIZING APPARATUS

Filed Sept. 13, 1941 3 Sheets-Sheet 1

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Sept. 24, 1946.

2,408,084

J. W. MARTIN

VAPORIZING APPARATUS

Filed Sept. 13, 1941

Sheets-Sheet 2

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<img file="US2408084A_D0003.tif" />

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INVENTOR.

/. fPooc/MYarc/ Mar'/Tn,

BY

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Sept. 24, 1946.

J. W. MARTIN

2,408,084

VAPORIZING APPARATUS

Filed Sept. 13, 1941

Sheets-Sheet 3

TO

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INVENTOR.

BY

Patented Sept. 24, 1946

2,408,084

UNITED STATES PATENT OFFICE

2,408,084

VAPORIZING APPARATUS

James Woodward Martin, Dallas, Tex., assignor to Lone Star Gas Company, Dallas, Tex., a corporation of Texas

Application September

Claims.

This invention relates to improvements in vaporizing devices, and more particularly to a vaporizer adapted for vaporizing liquefied hydrocarbon gases, such as propane, butane, proylene, butylene, etc., or mixtures thereof.

In my Patent No. 2,084,297,1 disclosed embodiments of a vaporizing apparatus, and set out certain objects relating to the treatment of liquefiable hydrocarbons such as propane, butane and their mixtures. The present apparatus have the same objectives, and may be used in the handling of propylene and butylene which were not specifically mentioned in my patent.

Another object of the present invention is to supply a vaporizing device that may be employed in a most efficient manner for heating various liquids, including water, whether for hot water or for steam generation. Naturally, if the liquid to be heated is not combustible, the fuel employed for heating can be supplied from an outside source.

My new vaporizer, or heat exchanger and combustion system has the advantage over the original ones, in that it can be constructed separate from the liquid container, and on a production line, using stamped parts and assembling such parts with a welding arc, gas torch, or by brazing or soldering, etc., or using castings or any other suitable method of construction and assembly. It will therefore be understood that it is a further object of this invention to supply a vaporizer that can be manufactured at less expense than the ones disclosed in my patent.

With the foregoing objects outlined and with other objects in view which will appear as the description proceeds, the invention consists in the novel features hereinafter described in detail, illustrated in the accompanying drawings, and more particularly pointed out in the appended claims.

In the drawings:

Fig. 1 is a vertical sectional view, partly in elevation, and partly broken away, of an embodiment of the invention.

Fig. 2 is an enlarged end view of a portion of the same, with the draft equalizer removed.

Fig. 3 is an elevation of an end plate forming part of the apparatus.

Fig. 4 is a vertical sectional view of a portion of a modification.

Fig. 5 is an end view of the same.

Fig. 6 is an elevation of an end plate forming part of the structure illustrated in Fig. 4.

Fig. 7 is a vertical sectional view of another modification, in which the fuel employed for

13,1941, Serial No. 410,766 (Cl. 62—1) heating purposes is supplied from an outside source.

The embodiment illustrated in Figs. 1 to 3 inclusive is quite similar to the structures disclosed 5 in my patent, but employs a heating device arranged at the bottom of the main storage tank. In this embodiment, 8 designates a main tank or container for any liquid that is to be heated. If it is used for liquefied gases, it may be pro10 vided with a safety valve 9 and a fill valve 10, the latter being arranged in a suitable housing I f secured to the bottom of the tank. Vapor from the vapor space 12 of such tank can be discharged through a pipe 13 which leads from the upper 15 portion of the interior of the tank through the bottom thereof, and is provided with a main vapor valve 14. Vapor, after passing through the valve, will flow through a conventional regulator 15 for maintaining on the valved service line 16 20 a reasonably constant pressure of any desired value less than the pressure in the tank 8. A service safety relief valve 17 is interposed in the service line between the regulator and the service cock 18; and a pressure gauge 19 and 25 removable cap 20 are preferably connected to a branch 21 of the vapor pipe 13.

A pipe 22 having a valve 23 leads from the pipe 16 and branches out into a pilot tube 24 and a pipe 25; the latter leading to a thermostatical³⁰ ly controlled valve or pressurestat 26 which controls the passage of vapor to a conduit 27 leading to a main burner 28. If the part 26, connected to pipe (3, is a pressurestat, it will be understood that as soon as the pressure of the 35 vapor in the pipe (3 decreases sufficiently, the valve between the conduits 25 and 27 will open, allowing vapor to flow to burner 28, so that the flame from the pilot 29 will ignite the vapor issuing through the burner 28. Obviously, the 40 pressurestat or thermostat may be connected directly to the tank 8 to allow either the pressure or temperature of the liquid or vapor to be used to control the flow of vapor to the burner.

To ignite the pilot, a spark-plug igniter 30 is 45 provided, which, by means of a battery and spark coil (not shown), causes a spark to jump from the electrode on the spark-plug across the spark gap to the top of the pilot, so as to ignite the vapor issuing therefrom. Obviously, any other 50 suitable safe means may be employed to ignite the pilot.

The pilot is located in a certain relationship to the burner (Fig. 1), so that in addition to providing the heat to keep the safety device open and to effect ignition of the vapor as it passes

2,408,084 out of the burner, it also keeps the burner barrel hot, thereby maintaining a draft through the inside of the barrel itself. (The barrel is that portion of the burner into which the vapor discharges and in which the primary air and the vapor mix.) By so doing, and when a modulating or throttling type control valve, either pressurestat or thermostat, is used, and when this control valve just barely opens or is nearing the closing off position, allowing but a small flow of vapor into the burner barrel, which flow has no velocity, said draft will cause even such a slight amount to rise to the combustion end of the burner barrel and ignite from the pilot. If this draft is not maintained within this burner barrel, heavy vapor (such as liquefied petroleum gas vapors) would flow out through the orifice in the lower end of barrel and accumulate in the bottom portion of the burner compartment as unbumed vapors. In time, a sufficient amount of such unburned vapors will accumulate and become ignited from the pilot, filling the burner compartment or box with burnt gas and extinguishing the pilot. Without the heat from the pilot directed on this burner barrel to maintain this draft condition, other means must be provided to prevent the results mentioned.

Heat from the burners travels upwardly through a vertical stack or flue 31, surrounded by a tubular insulation jacket 32 to prevent dissipation of heat. The flue has a beveled upper end, and a baffle 33 is rigidly secured to the uppermost edge of the flue and functions to divert combustion gases leaving the flue, into a heat chamber 34, the top of which is formed by the bottom of the tank 8, and to facilitate the heating of the contents of the tank, the bottom of the latter may be provided with protuberances 35 which extend into the heat chamber. The latter may be formed by a tube of U-shaped crosssection, as indicated in Fig. 2, and the sharply bent portions of this tube may be secured to the bottom of the tank by lines of welding indicated at 36. Due to this construction, opposite Ushaped walls 37 and 38 are spaced from one another to provide a U-shaped passageway 39 through which air for combustion may travel toward the burner and be preheated on the way. The left end of the wall 38 (Fig. 1) terminates at one side of the burner compartment or box while the wall 37 continues across the top of the burner box and is secured to an end plate 51 of the housing I i. The portion of the wall 37 which extends over the burner box is provided with an aperture for the reception of the parts 31 and 32 so that combustion gases from the burner box are constrained to travel through the flue 3 i and cannot reach the heat chamber 34 by passing about the exterior of the insulating jacket 32.

One end of the heating chamber is formed by a vertical plate 40 shown in detail in Fig. 3, and the upper curved edge 41 of such plate may be welded to the bottom of the tank 8. A flue 42 is cradled in the U-shaped tube and connected to the plate 40, and one end of the flue terminates at the outer end of the U-shaped tube and is located within a draft equalizer 43. The bottom portion of the flue 42 may extend into the heat chamber 34 and be secured to the top portion or wall 37 of the U-shaped tube, as shown in Fig. 1. The draft equalizer is in the form of a vertical tube having end closures 44 and 45 which are held in spaced relation to the tube by means of brackets 46, to provide an air intake 47 and a gas outlet 48. Due to my construction, hot gases discharged into the stack 31 will induce air for combustion to enter the inlet 50 of the U-shaped tube so that it may flow into the air passageway 39. The gases in this stack are hot (somewhere around 2000 degrees) and hence extremely light in weight as compared to air at normal temperature, and their velocity is great as well as is their lifting power. The .flame in this stack serves as a pump, pushing the products of combustion through the heat chamber 34, flue 42, and the outlet 49, and thence out through the aperture at the top of the draft equalizer, and at the same time sucks in or induces fresh air through inlet 50 and through the passageway 39 into the burner compartment.

The draft equalizer 43 serves to prevent any outside atmospheric disturbances such as windstorms or other storms, etc., from altering the direction of flow of the flue gases and the air and from extinguishing the pilot and/or burner flames.

The inner end of the heat chamber 34 is formed by an end plate 51 of the housing i i, and such end plate is preferably joined to the tank by means of welding. Such end plate also forms a partition between the instrument compartment and the burner compartment, and in order to facilitate the removal of the parts 28, 29 and 30 as a unit from the burner compartment, these elements are mounted on a plate 52 that is detachably secured to the end plate 51 by any suitable means, such as bolts 53. To accommodate such procedure, the pipes 24 and 27 are provided respectively with union joints 54 and 55.

At this point it will be noted that the burner compartment may be provided with a window 56, and that the housing 11 has one or more doors which may be locked to prevent unauthorized tampering with the parts which are arranged within the housing.

As before stated the insulating jacket 32 is supported by the U-shaped tube, while the flue 3i and its baffle 33 are mounted on the insulating jacket and supported on the latter by radial arms which are secured to the flue and rest on the jacket.

For the drainage of condensation from the chamber 34, a drain tube 59 extends downwardly through the burner compartment, and to prevent freezing of condensate in the tube during cold weather, the tube may be insulated as shown at 69 and extended into the ground (not shown).

It is believed that the operation of the apparatus will be obvious from the foregoing description, but it may be stated briefly that the heated gases resulting from combustion will flow from the burner 28 through flue 31 and heat chamber 34, so as to heat the contents of the tank, before the products of combustion are discharged through 42 and 43. Of course, the outgoing hot gases will also heat the incoming air travelling through the passageway 39. The element 26 will control the burner so that the burner will be ignited upon a predetermined fall of pressure or temperature of the contents of the tank.

In the structure illustrated in Figs. 1 to 3 inclusive, the tube 42 is not surrounded by the passageway 39 but merely in contact therewith. Where a greater amount of heating of the air for combustion is desired, the structure may be modified as illustrated in Figs. 4 to 6 inclusive. In this case, the U-shaped tube 60a will terminate at one end in a plate 61 that may be welded to the storage tank 62. A flue pipe 63 may be arranged within and be surrounded by an air in2,408.

take pipe 64, the latter being secured at one end to an apertured plate 65 that is detachably secured to the plate 61 by any suitable means such as screws 66. The outer ends of the tubes 63 and 64 are closed as.indicated at 67, and the flue 5 63 has an outlet sleeve 88, while the tube 64 has. an inlet sleeve 69. In this embodiment, the parts 63 and 64 may be removed as a unit to facilitate cleaning of the passageways through which the air and gases travel. . 10

In Fig. 7, I have illustrated an embodiment adapted for the heating of various materials by fuel from an extraneous source. In this case, the heating and burning unit may be welded to the bottom of the storage tank 70, and the fuel 15 for combustion purposes will enter the heating unit through a valved pipe 71 connected to branches 72 and 73, the former leading to a thermostatically controlled valve structure or pressurestat 74 which has an element 75 extending 20 into the tank. The instrument will control the flow of fuel through a conduit 76 to the main burner 77, which fuel will be ignited by the pilot burner 78.

In this embodiment, instead of supporting the 25 flue 79 by the insulating jacket 80, an elbowshaped flue may be used and its horizontal outlet portion 81 secured to the tank by a welded joint 82. Likewise, the type of flue having a baffle at the upper end as shown in Fig. 1, may be used and the baffle welded directly to the tank. With such arrangements, the heat from the flue will be directly imparted to the metallic shell of the tank.

While I have disclosed what I now consider 35 to be some preferred embodiments of the invention, it is manifest that changes may be made in the details disclosed, without departing from the spirit of the invention, as expressed in the claims.