DE2946176A1 - METHOD AND DEVICE FOR DISTRIBUTING NATURAL GAS - Google Patents

Description

PATENT LAWYERS DR. KADOR & DR. KLUNKER

K 12763 / 7h

Texas Gas Transport Company, Suite 304, 5407, N. IH-35, Austin, Texas 78723, USA

Method and device for natural gas distribution

The invention relates to a method and an apparatus for distributing natural gas from a supply station to one or more consumer connections. In particular, it relates to a method and a device for distributing natural gas to consumer connections without the use of a pipeline, the supply of the gas being essentially

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without interruptions and in such a way that the amount of natural gas transported per unit of work is ensured brings it to the maximum.

Natural gas is one of the most sought-after fuels, its immense Amount is available from boreholes all over the world. So far, the natural gas was by means of a Pipeline system collected from the boreholes and sent to a warehouse or directly to the consumer. In the last Time also turned to methods and devices for moving large quantities of natural gas to a store for subsequent distribution to consumers by means of devices other than pipelines. These processes and devices liquefy the natural gas as described in U.S. Patents 3,232,725 and

3,298,805 and transport it under high pressure as described in US Pat. No. 4,139,019. These new method of transporting natural gas from the natural gas well, in particular the method according to the US-PS

4,139,019 / has a large number of so-called trapped Boreholes for natural gas production opened, so that a much larger amount of possible fuel is available stands.

In U.S. patent applications Ser. 011 683 describes a method and a device or a system for ensuring the optimal extraction of natural gas from boreholes, which uses the high-pressure transport method according to US Pat. No. 4,139,019. This invention further contributes to the availability of natural gas as a fuel.

In times of energy scarcity, efforts are made to make full use of all available natural gas. With the use of pipelines, the liquefaction of natural gas and the new high-pressure transport methods, it is now

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more possible, significantly larger quantities of natural gas from the wells than was previously thought possible to win. This results in the problem of the uniform distribution of the extracted natural gas to potential consumers, so that the now more abundant source of energy can be used more fully.

Many potential natural gas consumers are located where pipeline construction is very difficult and expensive, such as in existing urban areas. Other potential consumers are about in relatively small numbers large geographical zones distributed, making the necessary economy for a pipeline laying easy is not given. In the latter, consumers are found, for example factories, schools, hotels and the like, which are located in all zones, almost all of which could use natural gas as energy if it were to Would be available. The situation also exists where ■ there is actually a sufficient number of consumers so that piping could be profitable, but where funding is not available until a corresponding market has been proven. In these cases, a pipeline could be laid if the Market, at least in part, would be tapped.

Many potential consumers of natural gas that fall into the groups shown are currently using propane, heating oil, Electricity and coal to meet their energy needs. In in many cases the use of natural gas would be much more desirable if it were available. Natural gas is a special one clean fuel, with which one can make decisive improvements in air quality, especially in older urban areas can be achieved if it is used instead of coal or heating

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oil uses. If natural gas were more readily available for the reasons mentioned above, it would be expected that it would would in many cases prove to be more economical than propane or electricity, for example.

The problem to be solved is how to effectively and economically get natural gas from a supply station can distribute to potential customers without laying a pipeline. With the necessary transport of the natural gas to the consumers the required mode of transport is connected in such a way that a uniform, trouble-free Supply is maintained. It is known that once technical equipment has been converted to natural gas, an interruption in the supply of natural gas can be both an inconvenience and a hazard. Under The distribution process must be a prerequisite for the demand for natural gas to change decisively from hour to hour and day to day be able to adapt to changing needs and at the same time be reliable and economical be. The present invention provides a method and apparatus for distributing natural gas that accomplishes this object solves.

According to the invention, natural gas is distributed from a supply station. The supply station can be connected to a natural gas field connected pipeline or can be a port storage facility for receiving in liquid state means of large F dgases transported by ships to the warehouse, whereby transports the natural gas by means of the method described in US Pat. No. 4,139,019 or a similar technical device became. The distribution method according to the invention begins at the supply station and is for supplying one or more remote consumer connections

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designed.

First, according to the method according to the invention, the consumer connection (or the consumer connections) examined to the required amount of natural gas over a certain Time to determine the expected fluctuations in consumption and other consumption-dependent factors. These dates the transport information, such as the distance to be driven, the Traffic conditions, the type of transport equipment available at the supply station associated amount of natural gas and flow rate and other factors. The distribution plan identifies the type and the number of transport pressure vessels required, the delivery schedules to be complied with and similar information.

The present invention relates to the high pressure transportation method according to US Pat. No. 4,139,019, which is intended to achieve an effective and economical natural gas distribution process has been modified. It also relates to those described in U.S. Patent Application Ser. 011 683 described Thoughts, especially with regard to the equipment to ensure automatic switching between two different pressure vessels, so that an uninterrupted flow of natural gas to the consumer connection is ensured is.

The device according to the invention comprises at least two Pressure vessels, of which at least one is between the supply station and the consumer connection to be supplied is movable. The other pressure vessel can also be moved or, if desired, permanently fixed to the consumer connection be arranged, provided that the

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allow other factors in the distribution plan to do so. The movable pressure vessel is at the supply station, such as in US Pat. No. 4,139,019 and, where possible, correspondingly to US Pat Ser.No. 011 683, loaded. The movable pressure vessel is then transported to the consumer connection where the natural gas is discharged.

The transport is carried out according to the distribution plan. The consumer connection is with a new arrangement equipped of components that ensure the appropriate implementation of the method according to the invention. the Apparatus at the consumer connection normally comprises a pressure control device, a safety control valve arrangement and a heater for the natural gas, together with an associated flow rate control · There are also precautions taken to switch between the connected pressure vessels, the device preferably being an automatic one Has switching, so that it is ensured that the natural gas flow to the consumer connection is not interrupted will.

It is the object of the present invention to provide a method and a device for distributing natural gas from a supply station to create a consumer connection (or connections) in which the supply is interrupted are as small as possible and ensure the greatest possible adaptation to changes in consumption.

This object is achieved by the characterizing features of claim 1.

With the method and the device according to the invention the labor costs for the transport of the natural gas per unit are kept as low as possible, whereby an economical

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lent supply of the not lying on a pipeline Consumer facilities is ensured.

The invention can be used in an advantageous manner to develop markets for the use of natural gas prior to building a network of pipelines to supply consumers and set up. With the invention it is possible in an advantageous manner, the number of personnel required to be kept as low as possible, with precautions being taken to ensure safe operation.

Embodiments of the invention are shown in the drawing and are described in more detail below. It demonstrate:

Fig. 1 is a schematic representation of a first embodiment of the unloading station in which the Device for discharging the natural gas is shown at the consumer station;

Fig. 2 is an enlarged partial view of the high pressure containers connected distributor for loading and unloading;

3 shows a schematic representation, similar to FIG. 1, of a further embodiment of the unloading station with a compressor for discharging the natural gas from the pressure vessels, the compressor being a Has bypass line with a flow rate control valve, which by means of the upstream Pressure is controlled; and

4 is an enlarged schematic partial view showing the automatic switching of the unloading device represents.

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US Pat. No. 4,139,019 describes a device for safely loading a pressure vessel with a certain amount of natural gas, normally at a pressure of approximately 138.46 173 kgf / cm ^2. It is believed that the high pressure transport method of this patent is used in the present process. Accordingly, the process steps associated with loading the pressure vessel are not described, but only reference is made to US Pat. No. 4,139,019.

As described in US Pat. No. 4,139,019, the pressure vessels have different shapes. For example, they can consist of a number of interconnected pressure vessels consist that are attached to a truck for overland transport or to railroad cars or to a boat are. To describe the invention it should be assumed here that the movable pressure vessel consists of a Number of interconnected pressure vessels, which are arranged for transport on a semi-trailer, wherein however, other arrangements are also possible.

The pressure vessels are loaded with certain amounts of natural gas at the supply station. As mentioned above, the supply station may be a pipe connection or any other connection to which natural gas is supplied. The method and the device allow the distribution of natural gas to one or more consumer connections, the can also be designed differently. For example The consumer connection can be the entry of a pipeline system in a factory, the entry line of a pipeline distribution system a settlement or a subdivision, the entry of a natural gas energy system of a Power station or a hospital or any similar

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before being a technical facility that supplies natural gas shall be.

In Fig. 1, an unloading station 2 is shown, which is located in the vicinity of a consumer connection 4. The unloading station 2 comprises a distribution system 6 with two unloading points 8, 10 for receiving the high-pressure containers to be unloaded Vehicles A and B. The vehicles A and B are shown in the drawing as semi-trailers 12, 14, which are loaded with high pressure vessels 16 and 18 and are connected to a motorized driver's cab 20,22. It is important that at least one of the two high pressure vessel arrangements A or B by means of a train, water power or as shown in the drawing is movable by means of a truck so that it can be used to transport a certain amount Natural gas can be used from a supply station (not shown) to the consumer connection. To have to at least two pressure vessel arrangements A and B are available for carrying out the method; in some cases however, additional high pressure vessel assemblies can be used.

If it is desired to use a stationary pressure vessel arrangement at the consumer station 4, this can be designed differently. In one embodiment, the pressure vessel assembly can be a simple parked one Be a semi-trailer 12 or 14 that is not moved. It can also be a large pressure tank or a series of interconnected tanks, a pipeline of particular Length, or any other suitable arrangement to accommodate a certain sufficient amount of natural gas can. The stationary pressure vessel must of course be filled with natural gas from time to time and be sufficiently large,

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a reserve supply in the event of unsuitable weather, a malfunction of the movable pressure vessel arrangement or other influencing factors or a similar emergency situation to ensure. The decision whether to use a stationary pressure vessel or not can be made by depend on many factors, including the expected length of time the pickup unit will be supplied and the amount of product to be supplied supplying natural gas. In some cases, the use of only movable pressure vessels will prove to be more appropriate turn out. This arrangement is shown in FIG.

In accordance with the teaching of US Pat. No. 4,139,019 and earlier US patent application Ser. 011 683, the pressure vessels 16 and 18 provided in the pressure vessel arrangement A and B must safely hold a certain amount of natural gas at a pressure of up to approximately 207.69 kgf / cm ² and above. Usually a number of cylindrical pressure vessels 16, 18 are mounted on each vehicle, all of which are connected to a common manifold. The high-pressure containers 16 are connected to a container manifold 24 by means of individual valves 26 provided with handwheels 28, each of which is provided with a bursting disc 30 or other suitable safety device to provide emergency relief in the event of excess pressure occurring while the associated valve 26 is closed. The illustrated valves 26 are operated by hand. It will be understood, however, that automatically operated valves can also be used as desired.

With the container manifold 24 is a connecting line 32 connected, the outer end of which is connected to a connector 34. With one side of the connector 34 is a filling line system 36 and at the other end

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Discharge line system 38 connected. The filling line system 36 includes a flow rate control valve 40, a drain valve 42 and an inlet port 44 disposed therebetween and one half 46 of a coupling 48 has. A one-way check valve 50 is between the flow control valve 40 and the connector 34 are provided to prevent backflow.

The discharge line system 38 includes a flow rate control valve 52 and a drain valve 54, between which an outlet connection 56 is arranged, one half 58 of a coupling having. The arrangement of the filling line system and the discharge line system 36 and 38, respectively, are similar to those described in US Pat. No. 4,139,019 and operate in US Pat same way as described there. The pressure vessels 18 of the pressure vessel arrangement B are with comparable filling line and discharge line systems 36 'and 38' and include flow rate valves 40 "and 52 ', drain valves 42 'and 54', a check valve 50 ', and coupling halves 46' and 58 '.

As stated in US Pat. No. 4,139,019, the drain valves 42, 42 ¹ , 54 and 54 'are used to relax the system prior to uncoupling. It is possible to dispense with the filling line system 36 and 36 'and to use only the discharge line systems 38 and 38' for carrying out the filling and unloading. The separate filling line systems with their additional couplings and non-return valves 50 and 50 ', however, create additional security insofar as a break in the filling line does not cause the high-pressure container to leak, since the non-return valves prevent an outflow. It can be sought to provide further relief devices in the system for additional emergency protection purposes.

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The distribution system 6 for unloading comprises a supply manifold or a supply line 60, which with a Feed line 6 2 is connected, which is connected to the consumer connection 4 for the supply of natural gas. With the opposite ends of the supply line 60 are connected to supply lines 66 and 68 leading to the unloading points 8 or 10 lead. In the supply line 60 there are two shut-off valves 70 on each side of the supply line 62 and 72, which are used to regulate the flow of natural gas from the unloading points 8 and 10. In the supply lines 66 and 68, one-way check valves 74 and 76 are provided, respectively, and the supply lines 66 and 68, respectively, end in flexible or adjustable discharge lines 78 and 80, coupling halves 82 and 84 at their outer ends for engagement with the coupling halves 58 and 58 '. The check valves 74 and 76 prevent backflow. Between the check valves and the discharge lines 78 and 80 is connected to the supply lines 66 and 68, respectively Drain valve 86 or 88 and an expansion valve 90 or 92, respectively. The drain valves 86 and 88 are used to drain of the pressure present in the system after the associated shut-off valve 70 or 72 is closed and before the coupling halves 82, 58 or 84, 58 'are uncoupled.

The one between the discharge lines 78 and 80 and the discharge line system Couplings used in 38 and 38 'can be of any type, but quick connect couplings are preferred used. The pressure relief valves 90 and 92 are used for safety, with their response pressure so is set so that the safety of the entire system and the operator is guaranteed.

Regarding the arrangement A and B of the high pressure vessel

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and the discharge line systems 38 and 38 'is the discharge distribution system identical in FIGS. 1 and 3. Accordingly, these components are not further described.

The distribution system 64 in FIG. 1 comprises a distribution line 94 which is connected to the consumer connection via a suitable Measuring device 96 is connected. The meter 96 can be a pressure meter, a flow meter, or both include. The inlet of a main shut-off valve 98 is connected to the supply line 62 for regulating the flow of the natural gas from the supply line 60 and the outlet of the main shut-off valve 98 is connected to the distributor line 94 .

In Fig. 1 it is assumed that the pressure of the natural gas prevails at the consumer connection 4 which is sufficiently low that unloading of the high-pressure gas from the pressure vessel arrangement A and B is possible essentially at any time without assistance. That is, the pressure of the pressure vessel assembly A and B is normally on the order of 138.46 207.69 kg / cm ³ and the pressure of the manifold connection is usually below 6.923 kg / cm ² , preferably in the range between approximately 3.46 kg / cm cm ² and about 13.85 kgf / cm ² . Under these conditions, no mechanical compression of the natural gas is required to convey it from the supply line 60 to the consumer connection 4. In order to carry out the method with a view to adapting it economically to demand and at the same time saving energy and ensuring a safe working environment, it is necessary that the flow rate of the natural gas is carefully regulated according to the distribution plan.

To regulate the pressure of the natural gas, which the consumer

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port 4 is supplied from the pressure vessel assemblies A and B in Fig. 1, a flow rate control valve 100 is in the distribution line 94 is provided, which is controlled by means of a controller 102 connected to the control valve 100, the regulator having a pressure branch line 104 connected to the manifold line 9 4 downstream of the control valve 100 is connected. The pressure control valve or the flow rate control valve 100 can be of any construction that achieves a variable flow orifice. A suitable valve is, for example, the commercially available "Fisher D Globe Style Valve" with a "4100 Series" Controller "which is arranged for back pressure regulation. The pressure regulating valve 100 is partially used to carry out the method necessary because, when the pressure vessel arrangement A and B is filled, the differential pressure between the consumer connection 4 and the pressure vessel is usually so large that, if it is fed directly to the consumer connection 4, it can pose a safety hazard, damage equipment, and cause other serious problems. The pressure regulating valve 100 serves to compensate for these potential problems by opening and closing and reducing the flow of the natural gas to the consumer connection 4 holds approximately at an acceptable constant pressure level, whereby both excessive pressures in the first stage of the discharge operation or very low pressures during the last stage of the unloading operation can be avoided. The pressure control valve 100 allows further changes in the natural gas demand at the consumer connection, whereby an economical operation is ensured.

A high-pressure shut-off valve 108 is provided between the control valve 100 and the consumer connection 4, preferably in the vicinity of the consumer connection. The valve 108 is controlled by a regulator 110, which has a pressure branch

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line 112 has upstream of the valve is connected to the manifold 94. The high pressure shut-off valve 108 is designed to shut off when the pressure in the distribution line 94, the safety pressure of the consumer connection 4 exceeds.

The natural gas transported in the pressure vessel assemblies A and B to the unloading points 8 and 10 is normally relative pure and free from moisture and liquid petroleum or the like. Technical facilities are accordingly usually not required to remove these contaminants from a consumer connection. However, if they do may be needed, a moisture trap and an oil-gas trap in the system shown in Fig. 1, preferably be provided in the supply line 60 or the supply line 62 upstream of the main shut-off valve 98.

The system shown in FIG. 1 further comprises a heater 114 arranged after the pressure regulating valve 100. The heater 114 is normally used to heat the natural gas so that its temperature is sufficiently high before it can enter the consumer connection enters, so that an embrittlement of the downstream of the heater 114 equipment is avoided. In some cases the heater can be omitted, but usually it is for successful Proceedings required.

Some consumer ports operate at a pressure significantly above the preferred range of 3.46 to about 13.846 kgf / cm ² , ie at or above the pressure of the natural gas in pressure vessel assemblies A and B, thereby creating difficulties in discharging the natural gas from the pressure vessels can arise. In these cases it is necessary

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to provide a compressor in the system (see Fig. 3). The components shown in Fig. 3, which correspond to those in Fig. 1, are provided with the same reference numbers.

3 shows several consumer connections 4, 4 ¹ with measuring devices 96, 96 ', which are connected to two distribution lines 122 and 124, which in turn are connected to the main distribution line 126. One-way check valves 132 and 134, respectively, are provided in the branch manifolds 122 or 124, and high pressure safety shut-off valves 128, 130 are provided downstream thereof, which correspond to the high pressure shut-off valve 108 in FIG. 1 and operate in the same manner. A heater 114 is normally located with the main manifold 126 upstream of the branch manifolds 122 and 124 and, as in FIG. 1, may be omitted under certain operating conditions.

The multiple customer distribution system according to FIG. 3 is a matter of course shown only as an example, i.e. that several consumer connections also with a single distribution line 126 can be connected. The same multiple arrangement can also be used in FIG. 1.

The system shown in Fig. 3 includes a compressor 120 and, by virtue of its presence, is the flow control valve 100 of FIG. 1 in FIG. 3 is not required. The compressor 120 is in between with the main manifold 126 the main shut-off valve 98 and the heater 114, with a one-way check valve 148 located upstream thereof is. A bypass line 138 is provided to bypass the compressor 120 and with the inlet opening and Outlet opening of the compressor connected. A flow rate control valve 140 is provided in the bypass line,

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which is controlled by means of a controller 142. The regulator 142 has a pressure branch line 144, which with the Main manifold 126 connected upstream of bypass line 138 and one-way check valve 148 is.

The compressor 120 is used to discharge the natural gas from the Pressure vessels of the pressure vessel arrangement A and B used and is used to regulate the flow rate of the natural gas to the connected consumer connections. Corresponding According to the method, the discharge operation should be carried out essentially uniformly, with no interruption in the Flow of natural gas when switching from one pressure vessel to the other occurs when the first pressure vessel is emptied. It should be noted, however, that this is not always accomplished for one reason or another so that a certain delay between the emptying of a container and the connection of the next container can occur. In such a case, the compressor bypass line is used.

When the pressure vessel connected to the distribution system 6 becomes empty, the pressure in the supply line 62 decreases. if this pressure drops below a certain value set in the regulator 142 and by means of the pressure branch line 144 is detected, the normally closed flow control valve becomes 140 opened, whereby the bypass line 138 is put into operation and the compressor 120 operates in a light idle mode. When the flow control valve 140 is open and the compressor is operating in light idling mode, the vacuum is on Entrance of the compressor 120 completely canceled, wherein the one-way check valve 148 is selected so that it

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under these conditions any reaction of the pressure from the pressure vessels or the distribution system 6 is prevented. The compressor 120 operates with minimal wear and tear during this light idling operation and requires minimal wear Amount of energy until the flow rate control valve 140 again is closed.

When the pressure upstream of the check valve 148 is completely built up again, e.g. when a full Pressure vessel is reconnected to the system, this pressure is detected by the pressure branch line 144 of the regulator and the flow rate control valve 140 is closed. The compressor 120 then again conveys natural gas under pressure to the consumer connection through the one-way check valve 148. The bypass arrangement serves to ensure that there is no negative pressure in the distribution system 6 and the pressure vessel occurs, thereby preventing air from entering the system, which could otherwise be caused by the compressor 120 generated vacuum could occur.

As already mentioned, the flow from the pressure vessels into the distribution line should take place without interruption. This requires an essentially simultaneous switchover from an emptied pressure vessel to a pressure vessel with a corresponding available amount of natural gas. Usually, the operator can use the shut-off valves 70 and 72 of the distribution system 6 manually operate in order to switch from an empty to a full pressure vessel without that there is a significant interruption in the flow of natural gas. However, the aim is to switch to this to be carried out automatically at a desired emptying point of the first pressure vessel. This becomes a uniform, economical operation guaranteed and

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In addition, in such cases, when no operator is available, or switching over by hand is not possible, security is guaranteed.

Referring to Fig. 4, there is an arrangement for performing an automatic switchover from an empty to a fuller container shown. In the figure, a loading distributor 200 connected to a supply line 202 is at its opposite side Supply lines 204 and 206 connected at the ends are shown. The load manifold 200 is with flow control valves 208 and 210, corresponding to the flow rate control valves 70 and 72, and the Supply lines have check valves 212 and 214, corresponding to check valves 74 and 76, drain valves 216 and 218, corresponding to drain valves 86 and 88 and Relief valves 220 and 222, corresponding to relief valves 90 and 92 of FIG. 1, on. With the outer Ends of the supply lines 204 and 206 are connected to discharge lines 224 and 226, respectively.

A connecting line 228, which connects to the two supply lines, extends between the supply lines 204 and 206 between the associated check valves 212 or 214 and the flow rate control valves 208 or 210 connected is. In the middle of the connecting line 228, a switchable control valve 230 is provided, which by means of a regulator 232 is regulated, which is provided with two pressure lines 234 and 236, which are connected to the connecting line are connected on opposite sides of the switchable control valve 230. The pressure branch lines 234 and 236, respectively are connected to a selector valve 238 which is arranged to have the lowest pressure in the two pressure branch lines 234 and 236 detected and only one

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Flow in the direction of the regulator 232 is permitted.

The switchable control valve 230 is initially closed and the pressure vessels are with both discharge lines 224 and 226 connected. The shuttle valve 238 then senses the lowest of the two operating pressures in the supply lines 204 and 206 prevail and, if the pressure in one of the supply lines falls below that in the regulator 232 set pressure drops so that the switchable control valve 230 is opened. The flow is then from the supply line 204 or 206 higher pressure directed to the lower pressure, using the appropriate check valves 212 or 214 prevent any backflow into the pressure vessel that has just been emptied. This is how the system becomes automatically switched from the emptied to the fuller pressure vessel.

The flow control valve is open some time after switching 208 or 210, which normally supplies natural gas to the supply line 202 from the now emptied pressure vessel, is opened, whereby the normal supply of natural gas is stopped and the other control valve 208 or 210 is closed. The supply line 206 or 208 coming from the emptied pressure vessel is then actuated of the associated drain valve 216 or 218, the pressure drop in the associated pressure branch line 234 or 236 is detected by the controller 232 and the switchable control valve 230 is closed. The empty pressure vessel is then replaced and the system works on it until the second pressure vessel is sufficiently emptied is, whereupon the switching process takes place again automatically.

The switching arrangement according to FIG. 4 represents a uniform

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Switching from an empty to a full pressure vessel safely, with no measurable interruption in the ongoing Natural gas flow occurs. This contributes to the achievement of one of the objects of the invention. There further the switching takes place automatically, it is not necessary for the operator to be overly attentive to the system to observe ,. allowing sufficient time to change the pressure vessel is available. This contributes to the security of the entire system and enables the entire device to the changing needs in a wide range that occur from time to time, can be customized.

If the method is operated accurately, it will provide minimal interruptions to the flow of natural gas at the consumer connection secure. The first step in the process is to study consumer needs to determine what amount of natural gas should be available. During this investigation, factors such as the rate at which the natural gas is consumed by the connected consumer devices, the changes and expected fluctuations in the weather, changes during the working weeks and the vacation periods and similar influences are taken into account and evaluated. Such procedures for Evaluations of this investigation are known in the industry.

The result of this investigation provides the maximum supply quantity, which is selected for the consumer connection. This will usually be two to three times that The average consumer amount of the consumer system. It should also be noted that the preferred supply amount can change over a period of time and accordingly a check in certain time

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The aim is to ensure a continuous and appropriate supply of natural gas.

Next, according to the method, the preferred production amount determined on natural gas at the supply station. The number of factors that need to be taken into account depend on the type of supply station and, in particular, on how the natural gas is transported to it. In In some cases the capacity of the supply station can be practically unlimited. In other cases, the production be limited.

Once a preferred supply rate and a preferred production rate have been selected, the next step is the selection the preferred number of separate pressure vessel assemblies and the nature of their operation required to achieve the Meeting demand and adapting to the production capacity of the supply station. In most cases it will a separate pressure vessel assembly consisting in a vehicle of suitable design that is movable from place to place and carries one or more pressure vessels in the manner described, be most suitable. The smallest The number of separate pressure vessels required to carry out the process is two; sometimes, however, are one or various additional separate pressure vessels for the continuous supply of the consumer connection or required to meet the given transport situation. At least one of the separate pressure vessels must be movable as mentioned above.

When the number of separate pressure vessel assemblies and their mode of operation is selected, different ones must be selected Factors are taken into account. The capacity of the separate pressure vessels for the selected operating

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pressure, which is usually between approximately 138.46 and 207.69 kgf / cm ² , the distance from the supply station to the consumer connection (or connections), the discharge rate at the consumer connection, the conditions of transport and that required between the supply station and the consumer connection Time and similar factors play a role. In any case, a production plan must be drawn up to ensure that the consumer connection is adequately and uniformly supplied with natural gas.

The type of vehicles used in the movable separate pressure vessel assemblies can be trucks, watercraft, Aircraft or possibly combinations of these. Usually, however, transportation is on Land by truck. If one looks at the pressure vessels attached to a semi-trailer in the drawing, so the minimum number to carry out the process is usually two such semi-trailers with pressure vessels and a driver's cab,. -to move them on the road. For isolated zones and consumer connections with a low natural gas requirement and when distances are short must be overcome, this minimum system is fully sufficient. It is also possible that only a separate The pressure vessel assembly is movable and the other is stationary; the switching required to create a continuous The gas flow is not impaired in this arrangement if the fixed, separate pressure vessel arrangement is filled with natural gas even at intervals.

To determine the adequacy of the equipment, one must calculate the following:

1.) The time required to fill a separate

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Pressure vessel assembly; and

2.) the length of time required for an unloading operation, the

(a) the time required to detach a movable, filled, separate pressure vessel from the supply station and to get ready to drive;

(b) the travel time to and from the consumer station;

(c) the time required to unload at the consumer station, which is of course determined by the rate at which the consumer station requires natural gas; and

(d) the time required to connect an empty, movable, separate pressure vessel upon return to the supply station.

If the discharge time is sufficiently within the filling time with some reserves for delays, this is the minimum Sufficient number of equipment. If this is not the case, there are usually several vehicles with pressure vessels, each representing a movable, separate pressure vessel arrangement is required. Among the ways of how one can enlarge the articulated lorry system, two examples should be explained:

System A

3 articulated lorry trailers with a system B cab

4 semi-trailers with two cabs.

Of course, other modifications are possible, which can be

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can turn, such as 4 or 6 trailers with 3 or 5 cabs. Each time, the goal is to have the lowest costs with an appropriate supply of the consumer connection (or the consumer connections) with natural gas within the production capacity of the supply station.

Once you have examined the values for the consumer connection and the supply station, and the number of After you have selected the pressure vessel and its mode of operation, this information is included in a distribution plan. Of the Distribution plan must also include a selection of the unloading system used at the consumer connection a decision about the need for a compressor included. With the distribution plan created, there is the next one Step of the method in the loading of a first pressure container arrangement and in its connection to the consumer connection. Then the second pressure vessel arrangement is loaded with a certain amount of natural gas and with connected to the consumer connection and prepared for switching. When the first pressure vessel up to a certain Point is emptied, the switch to the second pressure vessel is carried out, with no noticeable interruption the natural gas flow occurs and the first pressure vessel again with natural gas according to the distribution plan is filled. During unloading, natural gas is transported from the connected pressure vessel to the consumer connection, The flow is regulated to adapt to the needs of the consumer connection and the natural gas is normally is heated during such movement.

When all of the separate pressure vessel assemblies are movable they usually become the supply station for replenishment transported. If one or more of the separate pressure vessel assemblies is stationary at the consumer connection,

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it must of course be refilled from time to time at the consumer connection, preferably using a movable pressure vessel assembly.

After a switchover has taken place, the last method step consists in replacing the empty, separate one Pressure vessel by a full, separate pressure vessel in order to prepare the process for a new operating sequence.

In those cases in which only two separate pressure vessel arrangements are used and one of them is fixed at the consumer connection, the switchover carried out by the first, empty, movable, separate pressure vessel in the usual manner and the empty, movable, separate The pressure vessel is then removed and returned to the supply station. After filling, he returns to that Consumer connection and is reconnected to it. If the length of time compared to the capacity of the fixed pressure vessel is short, the refilling can be repeated a few or several times before the fixed pressure vessel must be refilled itself. The time between filling the stationary, separate pressure vessel can be expanded if the duration of its connection with the consumer connection is so short as possible. This is sometimes achieved by simply switching to the separate, movable pressure vessel, as soon as it is reconnected.

By increasing the number of movable, separate pressure vessels, it is possible to further reduce the time between to extend the filling operations of the fixed, separate pressure vessel. In the cases just described,

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the fixed, separate pressure vessel is only used to provide essentially continuous flow to ensure the consumer connection.

It should be noted that the present invention employs the high pressure transport method disclosed in US Pat. No. 4,139,019, in which the pressure vessels are not cooled, nor is the gas contained therein cooled. The natural gas is transported in discrete quantities at pressures of at least 55.384 kgf / cm ² , preferably about 103.845 kgf / cm ^2, and usually in the range of 138.46-209.64 kgf / cm ² . The method of transport of this patent makes the present invention possible because this method of transporting natural gas is both efficient and economical.

It was found that switching was done manually, however is preferably carried out automatically by means of the device shown in FIG.

There are, of course, various changes and amendments possible in the invention. It can also be seen that the method and device described the object of the invention solves, and that the invention is a distribution of natural gas in a continuous, uninterrupted and in an appropriate manner to allow consumer connections that are not connected to a pipeline are.

A method and a device are described in which a consumer system is provided with two unloading points is, and wherein at least two separate pressure vessel arrangements for supplying the consumer connection with natural gas are provided. At least one of the two separate ones

1 30019/0609

Pressure vessel can be moved to a supply station. The unloading station is preferably with an automatic Changeover switches are provided to switch from one pressure vessel to the other, thereby making use of the method and the device for natural gas distribution a continuous supply of natural gas at different demand rates the consumer connection is guaranteed.

ο 0019/0609

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L e r s e i t e

Claims (15)

PATENTAIVWALTE DR. KADOR & DR. KLUNKER K 12763 / 7h Texas Gas Transport Company, Suite 304, 5407 N. IH-35, Austin, Texas 78723, USA Method and device for natural gas distribution Claims 1 J Method and device for the continuous distribution of natural gas from a supply station to a consumer connection which is connected to a distribution system, characterized in that a first, movable, separate pressure vessel (16) is connected to the distribution system (6); Natural gas is discharged from the first, movable, separate pressure vessel (16) through the distribution system (16), the natural gas being discharged by means of a compressor 130019 / 060S ORIGINAL INSPECTED (120) is withdrawn from the first, separate pressure vessel (16) when the pressure of the natural gas in the first, separate pressure vessel (16) not above the pressure of the natural gas in the consumer connection (4) is around such a value that a uniform flow of the natural gas in the consumer connection (4) ensures, and that the unloading is carried out at a flow rate regulated so that a certain preferred supply of the consumer connection (4) is maintained; a second separate pressure vessel (18) with the Distribution system (6) connects before the first, movable, separate pressure vessel (16) completely is emptied; from the first, movable, separate pressure vessel (16) to the second separate pressure vessel (18) switches over when the first, movable, separate pressure vessel (16) has emptied a predetermined degree achieved, with no substantial interruption of the flow to the consumer connection (4) taking place; the second separate pressure vessel (18) in the same way as the first separate pressure vessel (16) emptied while the first, movable, separate pressure vessel (16) is removed and replaced; the filled, first, movable, separate pressure vessel (16) with full, movable, separate Replaced pressure vessels while the second pressure vessel (18) is emptied, and before its emptying is completed; and conveyed the empty, first, movable, separate pressure vessel (16) to the supply station which it is filled up, and then one to the consumer connection (4) returned, and then reconnects it to the distribution system (6). 130019/0809 2. The method according to claim 1, characterized in that one prior to the first-mentioned connecting selects a natural gas supply quantity for the consumer connection (4); - Determines a preferred amount of natural gas generated for the consumer connection (4); and you
the number of separate pressure vessels (16,18)
and the mode of operation of their operation selects to
to achieve the required selected natural gas supply quantity for the consumer connection (4) at the preferred natural gas production quantity, the number of separate pressure vessels (16, 18) being at least two, of which at least one is movable. 3. The method according to claim 1, characterized in that the second separate pressure vessel (18) is stationary, and that after the first, movable, separate pressure vessel (16) is reconnected to the distribution system (6) the natural gas flow from the fixed, separate pressure vessel (18) for emptying the full, first, movable, separate pressure vessel (16) is switched. 4. The method according to claim 1, characterized in that the second pressure vessel (18) is also movable. 5. The method according to claim 1, characterized in that the switching from the first, movable, separate Pressure vessel (16) to the second, separate pressure vessel (18) is carried out automatically when the first, movable pressure vessel (16) is emptied to a certain pressure level became. 3Ü019 / 0609 2945176 6. Device for the continuous distribution of natural gas from a supply station to a consumer connection, marked by - At least two separate pressure vessels (16,18), of at least one of which can be moved between the supply station and the consumer connection (4), and from both of which contain a separate, pressurized charge of natural gas; a loading device at the supply station for loading a separate pressure vessel (16, 18) with a certain amount of natural gas at a pressure above approximately 55.4 kgf / cm ² ; - A distribution system (6) connected to the consumer connection (4) for unloading - At least two unloading points (8,10) for the simultaneous reception of the separate pressure vessels (16,18); at least two supply lines (66,68), one of which is assigned to each unloading point (8,10) and which can be connected to the separate pressure vessels (16, 18); a distribution system (64) connected to the two supply lines (66,68) for unloading; a supply line (62) connected to the manifold system (64); - A distribution line (94, 126) connected to the supply line (62) and to the consumer connection (4); - Regulator (102, 142) and flow rate control valves (100, 140) for regulating the flow rate of the natural gas from the supply line (66,68) to the consumer connection (4). 7. Apparatus according to claim 6, characterized in that 130019/0609 that the supply line (62) between the two supply lines (66,68) is connected to the distribution system (6), and the control comprises a pair of flow control valves (70,72) mounted in the distribution system (6), one of which one in each case is arranged between the supply line (62) and each supply line (66,68). 8. Apparatus according to claim 7, characterized in that between the two supply lines (66,68) devices for automatically switching the natural gas flow from a first, connected to a first supply line (66), separate pressure vessel (16) to a natural gas flow from a second, with the other supply line (68) connected, separate pressure vessel (18) as a function of the decrease in pressure below a predetermined value are arranged within the first supply line (66). 9. Apparatus according to claim 8, characterized in that the switching device a connecting line (228) extending between opposite ends of the two supply lines (204,206) extends and is connected to them, a one-way check valve (212,214) in each supply line (204,206) upstream of the connecting line (228), a switchable control valve (230) in the connecting line (228), - A regulator (232) for the switchable control valve (228) with two pressure lines (234, 236) which are connected to the connecting line (228) on opposite sides of the switchable control valve (230), and
a selector valve connected to the regulator (232) i30019 / 0609 294S176 (238) comprises that between the pressure lines (234, 236) for detecting the pressure of the operating Supply line (204,206) is arranged. 10. The device according to claim 9, characterized in that at the outer ends of each supply line (204,206) provided for releasable connection to an assigned, separate pressure vessel (16, 18), connecting devices (224, 226) are, and that a drain valve (216,218) between the connecting device (224,226) and the associated flow control valve (208,210) upstream of the associated respective check valves (212,214) with each Supply line (204,206) is connected. 11. Apparatus according to claim 6, characterized in that for controlling the carrying out. ^ ¹ ußmenge of natural gas through the manifold (94), a driven means of a regulator (102) A flow control valve (100) is provided, wherein the controller with the pressure downstream of the control valve (100) works. 12. The device according to claim 6, characterized in that the device for regulating the flow rate of the natural gas through the manifold (126) has a compressor (120). 13. The device according to claim 12, characterized in that that the compressor (120) with the distribution line (126) is connected that a bypass line (138) with the distribution line (126) is connected and connects the outlet side and the inlet side of the compressor (120) to one another, that a flow rate control valve (140) is arranged in the bypass line (138) that a controller (142) for the Flow control valve (140) with a pressure line (144) 130019/0609 is provided, the pressure line being connected to the distribution line (126) upstream of the compressor (120) and that a one-way check valve (148) upstream of the compressor (120) in the distribution line (126) between the pressure line (144) and the inlet of the Compressor (120) is arranged. 14. The device according to claim 6, characterized in that that a heater (114) is arranged in the distribution line (94, 126) upstream of the consumer connection (4). 15. Apparatus according to claim 6, characterized in that that a high pressure safety valve (108,128,130) with the Distribution line (94,122,126) upstream of the consumer connection (4) is connected, which comprises a regulator (110) with a pressure line (112) which is connected to the distribution line is connected upstream of the high pressure safety valve. , 30019/0609