DE2144073A1 - Device for storing and dispensing liquid gas - Google Patents

Description

PATS) 5TAKWAM DIFL. ING. K. HOLZEB

89 AUGSBURG

THERE

K. 389

Augsburg, September 1, 1971

The British Oxygen Company Limited, Hammersmith House,

London W6 9DX, England

Device for storing and dispensing liquid gas

The invention relates to devices for storing and dispensing liquid gas

Known devices for dispensing liquid gas normally have a vessel containing the liquid gas, a line connected to this vessel for dispensing the

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Liquid gas and devices for increasing the pressure inside the vessel by evaporation of the contained therein Liquefied gas on «

In such known devices, the pressure increasing system has a line in which the liquid gas flows from the bottom of the vessel into a heat exchanger, in which it is evaporated, and another line which carries the steam from the heat exchanger into a vapor space in the upper part of the vessel · A valve is arranged in one line so that the liquid gas flow into the heat exchanger can be regulated during operation or, if the vessel is not in operation, it can be blocked. However, such pressure increase systems have the disadvantage that in case of leakage of the valve, an undesirable liquid loss occurs and / or the pressure is increased within the vessel · Moreover, the presence of an afferent to the base of the vessel conduit is undesirable because they provide a path for the flow of heat in the liquid gas forms

The invention aims to solve the problem

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a device for storing and dispensing liquid gas to improve the pressure booster works valveless and that there is no pipeline through which an undesirable inflow of heat into the liquid gas takes place.

In order to achieve this object, the invention includes a device for storing and dispensing Liquid gas, which is characterized by a vessel closed with a lid, and also by a Dispensing tube passed through the lid, which connects part of the interior of the vessel in the vicinity of the lid and an outlet for the discharge of the liquefied gas in liquid or vapor state manufactures, and by a heating device for the evaporation of liquid gas, which is with the heating device is then in contact when the vessel is inverted, the liquefied gas vapor formed being the pressure in the Increased vessel and the delivery of liquid or vaporized liquefied gas, depending on the position in which the The vessel is located under pressure.

According to the invention, the heating device, which

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causing the increase in pressure is valveless.

After the pressure in the vessel on the liquid dispensing If the desired value has been increased, the delivery takes place with the vessel in its upside down position is held. On the other hand, evaporated liquid gas is released either by turning the vessel back into its starting position or by leaving the vessel in its upside down position and by connecting a heat exchanger to the delivery pipe, this heat exchanger the liquid gas flowing through it evaporates.

The invention also includes a method of dispensing vaporized liquefied petroleum gas from that described above Device according to the invention, which is characterized by the following steps:

a) Turn the vessel over so that the liquid gas comes into contact with the heating device and evaporates will,

b) Introducing the vaporized liquefied gas into a vapor space above the liquefied gas,

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c) turning the vessel back into its normal position when the pressure in the vessel has reached a certain level Has reached value, and

d) Dispensing of the vaporized liquid gas via the dispensing line

The invention also includes a method for dispensing vaporized liquefied gas from the device according to the invention, the delivery pipe of which is connected to a heat exchanger, which by the following steps is marked:

a) Turn the vessel over so that the liquid gas comes into contact with the heating device and evaporates will,

b) introducing the vaporized liquefied gas into a vapor space above the liquefied gas, and

c) Introducing the liquid gas into the heat exchanger connected to the discharge line when the pressure in the vessel has reached a certain value

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In general, the heating device draws its heat energy from the surroundings. In a further development of the invention the heating device is a heating block, which has the shape of the lid and is either solid or has one or more channels inside. In another embodiment of the device according to the In accordance with the invention, the heating block has the shape of a pipe coil, which is arranged around the lid

The heating block can also be formed from one or more pieces of material with high heat capacity, which or which are arranged in the interior of the vessel in the vicinity of the lid. The heating block can for example be a housing which is suspended from the lid of the vessel and which contains lead shot. When the vessel in its normal position, i.e. in its initial position, the steam surrounding the housing isolates it versus the liquefied petroleum gas inside the vessel · However, if the vessel is upside down, the liquefied gas will touch the heating block and extracts heat from it

If the vessel is double-walled and if insulation is provided between the walls, the heating block between these walls can be in heat

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Contact with an area of the outer surface of the inner wall in the vicinity of the lid. Preferably a shield is provided which covers the inner surface of the wall area with which the heating block is in thermal contact is, protects. This prevents the Heating block is cooled by this during the filling of liquid gas into the vessel.

The heating block is usually insulated. The mass and the specific heat of the heating block can be adjusted accordingly the desired flow of heat into the vessel can be selected.

The device according to the invention can be provided with a heating block of limited heat capacity so that Under normal operating conditions, excessive pressure build-up within the vessel is not possible.

The heating device can optionally be a heat exchanger which, in contrast to a heating block, is traversed by a fluid.

According to the invention, this heat exchanger is provided with a line which passes through the cover

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connects to a part of the vessel near the lid, and with one also through the lid Connected further line leading into the interior of the vessel, so that to increase the pressure a reversal of the Vessel is required.

In a further method for dispensing gas from that device according to the invention, which one for increasing the pressure serving heat exchanger and in which the further tube in a remote from the cover At the end of the area of the vessel, another heat exchanger is connected to the Plilssig gas discharge pipe and leave the vessel in its inverted position during the entire dispensing process.

In another preferred embodiment of the device according to the invention, the further line ends in a region of the interior of the vessel adjacent to the lid. An outflow of vaporized liquid To ensure from this line end, the further line preferably protrudes further into the interior of the vessel than the one line. In addition or in addition, a device can be provided which a flow of

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Liquid through the heat exchanger used to increase the pressure initiates through. For example, the end part of the further line can be in the form of a pipe coil for this purpose or a U-tube, the outlet of which is opposite the lid of the vessel. When LPG is dispensed is to be, the vessel is turned over and liquid gas flows into the heat exchanger used to increase the pressure one in which it is vaporized. The liquefied gas vaporized in the process passes through the liquid in the vessel through into the vapor space above the liquid. When the pressure inside the vessel has a certain value has reached, the dispensing tube is opened and liquid is dispensed. If gas is to be released, it will The vessel is then turned back to its original position when the pressure has been increased to a desired value. Thereafter the valve in the dispensing tube is opened.

This embodiment of the device according to the invention and, moreover, those embodiments of the Device according to the invention, which have a heating block, offer both the gas and the Liquid delivery has the advantage that the vapor in the space above the liquid is in equilibrium with the same is. This balance is achieved by the

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vapor emanating from the heat exchanger or heating block is passed through the liquid in the vessel will. The beneficial consequence of the liquid-vapor equilibrium is that during the delivery of Liquid or gas the pressure within the vessel remains essentially constant, so that the delivery with can take place essentially constant speed or amount.

The heat exchanger used to increase the pressure can be switched on with one line and with the other line form a common part. It must be able to withstand the pressure of the liquefied gas and should therefore for example, be of cylindrical or plate-shaped design. Preferably it is in the form of a Cover arranged around the pipe coil.

In addition, the heat exchanger used to increase the pressure can form a common part with the cover or be arranged within a lid which has a large heat capacity. With this arrangement the lid is ribbed to improve the heat transfer from the environment to the liquid gas.

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21U073 44

In that device according to the invention which has a discharge heat exchanger, construction and Dimensions of the lid, the discharge heat exchanger, the booster heat exchanger and the discharge pipe preferably chosen so that the heat transfer from the environment to the liquid gas is the desired amount or Speed of gas delivery causes. In such a device according to the invention is also when instead of a heating block, a pressure-increasing heat exchanger has been chosen, the cover expediently endowed with a large heat capacity by being made of a material of high specific heat will. Such a lid creates a good heat transfer from the environment to the liquid gas when the vessel is turned upside down is. When the vessel is in its starting position, the vapor space forms between the liquid gas level and the lid an insulation for the liquid gas

In addition, the liquid gas delivery pipe should be insulated so that the evaporation of the liquefied gas within the heat exchanger can be controlled. The discharge heat exchanger is preferably easy with the outlet of the liquefied gas delivery pipe via one or more removable pipe couplings connected. This connection

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can be done, for example, via a flexible coupling. Such a coupling connection enables an empty vessel to be easily replaced by a full one. The outlet of the discharge heat exchanger is preferably provided with a gate valve and with a gas flow spreader Mistake.

The discharge heat exchanger is preferably made of a material of high thermal conductivity and lower Density. For example, aluminum is a particularly suitable material. The discharge heat exchanger is for example cylindrical or plate-shaped. One inexpensive type of discharge heat exchanger is a around the vessel is a coiled pipe. The discharge heat exchanger can also be in a support frame be accommodated to which the vessel is attached · Accordingly, a holding frame with a pipe coil another inexpensive embodiment of a discharge heat exchanger

If the output quantity from a heat exchanger is to be increased, an additional heating device can be provided. will see, for example in the form of a hot water jacket

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In the embodiment of the device according to the invention, which has a pressure-increasing heat exchanger, advantageously have the discharge pipe and that to the pressure-increasing heat exchanger a pipe leading to a common inlet.

There should be a valve in the delivery pipe or in a device into which the liquid gas is fed. This valve is opened when a pressure suitable for dispensing liquid gas has been built up. This valve can work automatically if it has been set so that it opens at a certain pressure. In general, a pressure in the range from 15 bar to 20 bar is suitable.

For ventilation, the liquid gas dispensing device according to the invention is preferably provided with a pressure relief valve This valve can be provided in a pipe passage which is connected to the delivery pipe If necessary, the valve can be used to reduce an excessively high internal pressure before the vessel is filled.

The lid is fluid-tight with the vessel

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connected and preferably provided with a protective shield, which protects it from damage «In particular, when the heating block or pressure-increasing heat exchanger is arranged in the form of a pipe coil around the cover is, the shield also serves to protect the pipe coil, the lid can be made of brass, copper or, for example stainless steel.

The vessel is preferably vacuum insulated · an insulating powder or spaced apart Layers of insulation material can improve the insulation effect between the vessel walls, which enclose the evacuated space, be arrangedThe inner wall must be constructed in such a way that it can withstand the pressures, which are reached during the delivery of liquid gas, withstands. The vessel can, for example, have an inner wall made of stainless steel with a large wall thickness and an outer wall made of stainless steel with a smaller wall thickness « The vessel can also be provided with tensioning anchors or ropes, for example made of stainless steel which reduce the stresses caused by turning the vessel over

In order for the jar to be easily turned over, it is

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held in a holding frame which is mounted on a trolley. For attaching the vessel to the Retaining frames are preferably used with easily detachable connections. Such connections are, for example, spring joints The vessel can also be rotatably mounted on a holding frame, which on the frame of a Trolley is attached.

The liquid gas dispensing device according to the invention has numerous advantages over known devices of this type. In known devices there is a risk that the operation of a valve provided in the pressure-increasing device will be impaired by the formation of frost. In the device according to the invention, this risk is avoided by a valve-free pressure-increasing device. In particular, a valveless pressure increasing device which does not receive any liquid when the vessel is in its normal position, that is to say in its starting position, enables the reliable storage of liquid gas. The attachment of the pressure increasing means at the lid of the vessel allows for a vessel structure in which no _s are available through the vacuum insulation projecting through pipes so that the problem of heat influx is not along such tubes in the vessel.

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Attaching the heat exchanger or »the heating block on the lid of the vessel enables a particularly robust vessel construction.

Another advantage of the device according to the invention is that the delivery tube in a nearby of the lid located vessel area ends, so that no flushing line needs to be provided in the vessel. Rather, the vessel is filled with liquid gas by simply removing the lid and the liquid gas directly is filled from a storage tank.

The device arrangement, in which the pressure is increased by turning the vessel upside down, also has the advantage that it is only necessary to determine whether the pressure increasing system is in operation is to look at the position of the vessel. In known vessels of this type, a pressure gauge must be provided for this be. In addition, the device according to the invention is so constructed that the vessel is easily turned over and with the help a trolley can be easily transported. A portable or transportable liquid gas source is particularly desirable for many welding and flame cutting work,

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Another advantage of the liquid gas dispenser according to the invention is that it can deliver liquid or gas. A particularly favorable construction of the device according to the invention for supplying gas is achieved by using easily removable connections between the holding frame and the vessel and between the discharge heat exchanger and the outlet of the discharge line. With this arrangement, the outlet of the discharge heat exchanger can remain connected to a device which is being supplied with gas, while an empty liquid gas discharge device is replaced by a full device. Furthermore, the mounting of the discharge heat exchanger around the vessel or in a support frame allows a robust construction. The device according to the invention is particularly easy to operate and can be designed so that it automatically delivers gas after turning it over, the gas flow being controlled by actuating a control member.

Several exemplary embodiments of the invention are illustrated in the drawings and are described below described in more detail. Show it:

Fig. 1 schematically shows an embodiment

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2K4073 4g

form of a device according to the invention, which is set up for the delivery of liquid gas is,

Fig. 2 that is on a trolley

brought device according to Fig. 1,

3 schematically shows another

Embodiment of the device according to the invention, and

4 to 6 each still further embodiments of the device according to the Invention, in each of which a heating block is used to increase the pressure.

According to the illustration in FIGS. 1 and 2, a vacuum-insulated vessel 2 is on a protective base 30 attached. A lid 4 is seated in a fluid-tight manner on a neck 5 of the vessel 2. One used to increase the pressure Heat exchanger coil 6 passing through the cover 4

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2H4073

is passed through, is via a line 8 with part of the interior of the vessel in the vicinity of the lid 4 in Link. The heat exchanger coil is also connected to part of the interior of the vessel via a countersink tube 10, which is remote from the lid 4, in communication. A likewise arranged in the cover 4 Plüssiggasabgabeerohr 12 leads to a discharge heat exchanger 28, the via a flexible coupling 26 with the Tube 12 is connected. The heat exchanger 28 is connected to the base 30 via spring joints 38 and also provided with pressure pads 42 which rest on the vessel 2. The heat exchanger 28 is shown in FIG. 2 by means Trunnion 44 is pivotally mounted on a trolley 46.

When the vessel 2 is in the position shown in FIG. 1, a liquid gas level is sufficient in its interior so far that the line 8 and the pipe 12 with the vapor space above the liquid gas level in connection are and that there is no differential pressure between the sink pipe 10 and the line 8, the one Liquid gas flow caused by the coil 6 therethrough.

When the vessel 2 is turned over, i.e. pivoted by 180 °

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is, the line 8 and the pipe 12 are in communication with the liquid gas. By turning the vessel upside down, a liquid pressure is formed within it, which presses the liquid gas through the line 8 into the coil 6. Steam then emerges from the lowering tube and enters the part of the interior of the vessel that is removed from the cover 4. Before turning around, this part of the interior, in which there is now steam, was occupied by liquid gas. As the amount of steam penetrating into this vapor space increases, the pressure exerted on the liquid gas by this vapor increases. The inner wall 20 of the vessel 2 is made of stainless steel and has a large wall thickness so that it can withstand this pressure. In order to prevent damage to the neck 5 of the vessel 2, steel pull cables 2k are arranged between the inner wall 20 and the outer wall 22. When the pressure in the vessel 2 reaches a suitable value, a gate valve 14 arranged in the liquid gas discharge pipe 12 is opened so that liquid gas can flow into the discharge heat exchanger 28, in which it is evaporated. The speed at which gas exits from an outlet 36 of the heat exchanger can be controlled by a control element 32, which is a

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Has a safety valve and a gate valve 34, being controlled.

A load measuring device 40, which is connected between one of the spring joints 38, shows the amount of Liquid gas in the vessel 2. One in a line 16, which is in communication with the pipe 12, arranged Pressure relief valve 18 opens when the pressure in vessel 2 exceeds a certain value.

The device shown in Fig. 1 is set up for the delivery of gas, but it can easily can be adjusted to dispense fluid by disconnecting the flexible coupling 26 from the tube 12 will.

The embodiment shown in Fig. 3 of the Apparatus according to the invention is generally similar to the embodiment shown in FIG. The device according to However, FIG. 3 does not include the discharge heat exchanger or valves 32 and 34. The reference number 28 in this embodiment denotes a holding frame for the vessel 2. Another difference is that the countersunk tube 10 is in a region of the

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Vessel interior in the vicinity of the lid 4 ends, but that it is like that in Pig. I illustrated embodiment of the device according to the invention is longer than that Line 8.

When the vessel 2 is turned over, the liquid gas reaches the one in the immediate vicinity of the cover 4 Area of the interior of the vessel its lowest level. As a result, a liquid pressure forms in the interior of the vessel from which a liquefied gas flow from the inlet of line 8 through the pressure increasing heat exchanger coil 6 through to the outlet of the sink tube 10 is generated. The liquid gas is in the Heat exchanger coil 6 evaporates and passes through the liquid in the form of bubbles into the Vapor space above the liquid. The vapor passing through the liquid in the form of bubbles causes the vapor to be in equilibrium with the liquid.

When the pressure has reached the desired value within the vessel, the gate valve 14 is, if liquid is to be delivered, opened, when

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on the other hand, gas is to be delivered, the vessel is turned back to its normal position and the gate valve 14 then opened. When the vapor is in equilibrium with the liquid in the vessel, it becomes gas or liquid dispensed at a substantially constant rate.

In the device according to the invention shown in FIG. 4, the cover 4 forms a heating block which consists of copper and is provided with an insulating cap 48. The delivery pipe is the only pipe that leads through the lid.

When the vessel 2 is turned over, the liquid gas contained therein comes into contact with the cover 4. Heat transferred from the cover 4 to the liquid gas leads to the evaporation of part of the liquid gas. The liquid evaporated in this way enters the vapor space above the liquid in the form of bubbles. As in the case of the device shown in FIG. 3, a liquid-vapor equilibrium is thereby created.

When the pressure within the vessel has reached a desired value, the process with reference to FIG

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Pig. 3, liquid or vaporized liquid can be dispensed.

For a vessel with a fit of 50 liters, which contains 40 kg of liquid nitrogen, is increased by an insulated heating block made of 3 kg of copper the pressure inside the vessel to 10 bar.

Two other embodiments of a heating block are shown in Figs. The heating block of FIG. 5 is a copper ring 50, which within of the vacuum-insulated space of the vessel and is in thermal contact with the neck of the inner wall 20. A substantially cylindrical shield 52 is over insulation pieces 54 on the outer surface of the neck attached to the inner wall 20 and prevents the cooling of the during the filling of liquid gas into the vessel Copper ring 50 through this liquid gas.

The embodiment shown in Fig. 6 of the The heating block consists of a housing 60 filled with lead shot 62, which extends from the cover 4 into the neck of the interior of the vessel is suspended.

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Claims (20)

2U4073 Claims lyDevice for storing and dispensing liquid gas, characterized by a vessel (2) closed with a lid (4), and also by a vessel passed through the lid Dispensing tube (12) which connects a part of the interior of the vessel in the vicinity of the lid and an outlet (14 or 36) for discharging the liquefied gas produced in liquid or vapor state, and by a heating device (6, 10 or 50 or 60, 62) for the evaporation of liquid gas, which is in contact with the heating device when the The vessel is turned upside down, the liquefied gas vapor formed increasing the pressure in the vessel and the discharge of liquid or vaporized liquid gas, depending on the position in which the vessel is, under pressure. 2. Apparatus according to claim 1, characterized in that the heating device (6, 10 or 50 or 60, 62), which causes the pressure to increase, is valveless. 3. Device according to claim 1 or 2, characterized - 25 209812/1047 21U073 46 shows that the vessel (2) is vacuum-insulated. 4. Device according to one of claims 1 to 3, characterized by one connected to the delivery tube (12) Heat exchanger (28). 5. Apparatus according to any one of claims 1 to 4, characterized in that the heating device is a heat exchanger (6) is. 6. Apparatus according to claim 5 »characterized in that the heat exchanger (6) with a line (8) which connects this through the lid (4) with a part of the vessel (2) in the vicinity of the lid, and with another line (10), which also leads through the lid into the interior of the vessel, is connected, so that it is necessary to turn the vessel upside down to increase the pressure. 7. Apparatus according to claim 5 or 6, characterized in that the heat exchanger (6) serving to increase the pressure is a coil wound around the cover (4). 8. Apparatus according to claim 6, characterized in that - 26 -209812/1047 21U073 that the further line (10) in a region of the interior of the vessel ends in the vicinity of the cover (4) and that steam can escape at this end of the line. 9. Apparatus according to claim 6, characterized in that the further line (10) in one of the cover (4) distant area of the interior of the vessel ends. 10. Device according to one of claims 5 to 9 »thereby characterized in that the heat exchanger (6) used to increase the pressure has a joint with the cover (4) Part forms or is housed within the same. 11. Device according to one of claims 1 to 4, characterized in that the heating device is a heating block (4, or 50 or 60, 62). 12. Apparatus according to claim 11, characterized in that the cover (4) forms the heating block. 13. Apparatus according to claim 12, characterized in that one or more channels are formed in the cover (4) are. - 27 209812/1047 14. Apparatus according to claim 11, characterized in that the heating block has the shape of a coil (6). 15. Apparatus according to claim 11, characterized in that the heating block consists of one or more parts (4, 48 k or 50 or 60, 62) is made, the material of which a has high heat capacity and which are arranged within the vessel (2) in the vicinity of the lid (4). 16. Apparatus according to claim 11, characterized in that the vessel (2) is double-walled (20, 22), that further insulation is provided between these walls and that the heating block (50) between them Walls in thermal contact with an area of the outer surface of the inner wall (20) in the vicinity of the lid (4) "is arranged. 17. Apparatus according to claim 16, characterized in that the inner surface of the wall area (20) with which the heating block (50) is in thermal contact, protective shielding (52) is provided, which while the liquid gas is being introduced into the vessel (2) - 28 - 209812/1047 2U4073 this liquid gas prevents the heating block from being cooled. 18. Apparatus according to any one of claims 11 to 17, characterized in that the heating block is insulated. 19. A method for dispensing vaporized liquid gas from the device according to claim 1, characterized by following steps: a) Turn the vessel over so that the liquid gas comes into contact with the heating device and is vaporized, b) Introducing the vaporized liquefied gas into a vapor space above the liquefied gas, c) turning the vessel back into its normal position when the pressure in the vessel has reached a certain value, and d) Dispensing the vaporized liquefied gas via the dispensing line. - 29 209812/1047 20. Method of dispensing vaporized liquefied petroleum gas from the device according to claim 4, characterized by the following steps: a) Turn the vessel over so that the liquid gas comes into contact with the heating device and evaporates will, b) introducing the vaporized liquefied gas into a vapor space above the liquefied gas, and c) Introducing the liquid gas into the heat exchanger connected to the discharge line then, when the pressure in the vessel has reached a certain value. - 30 209812/1047