DE1191245C2 - Ship for storing and transporting liquefied gases at around atmospheric pressure - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

PATENT LETTERING

Int. Cl:

Number:

File number:

Registration date:

Display day:

Issue date:

B63b

German class: 65a2-30

1191245
C21182XI / 65a2
April 9, 1960

April 15, 1965

December 16, 1965

The patent specification corresponds to the patent specification

It is known to have a solid support column in a container for the transport of liquids by ship to be rigidly connected to the ship's structure. The inner tank is attached to the support column by struts attached. The support column is made of layers of an insulating material and these in turn surrounded by a sheet metal jacket. In this known arrangement, the column only has the task of to hold the inner tank in place. No pump can be arranged in its interior.

A fuel tank with a pump has also been designed with a tube extends downward from the tank top and envelops at least part of a pump assembly. the The purpose of the known arrangement is to prevent fuel from entering the electric motor. to For this purpose, the end of the tube in which the motor is located is filled with oil or grease, i.e. with Substances which, because of their hydrostatic pressure, ensure that the fuel does not start the engine achieved. There are therefore the following differences compared to the present invention:

1. As the tube is filled with oil or grease, the motor is difficult to access.

2. The tube has only a small diameter, so that no one has to run , Repairs could get into the tube.

3. The pump is practically outside the tube.

4. The tube is not attached to the bottom of the tank and therefore cannot be used to reinforce it contribute.

5. The tube is not thermally insulated.

6. The tube does not extend downward beyond the bottom of the tank, so that a fastening of the tank in the hold is not possible in this way.

7. The tube does not extend upward either over the top of the tank so that there is no possibility of anchoring there either.

According to older proposals, the liquefied natural gas is housed in large metal containers which are built into the hold of a ship, which contain an outer and an inner shell made of metal. The inner shell is separated from the outer shell by side tanks. The hold is completely insulated with the help of a material that does not conduct heat well; the insulation material is attached to the inner surfaces of the inner hull to provide heat conduction to the inside of the insulated cargo ship for storage and transportation
liquefied gases at around atmospheric pressure

Patented for:

Conch International Methane Limited,

Nassau, Bahamas (UK)

Representative:

Dr.-Ing. F. Wuesthoff, Dipl.-Ing. G. Pulse and
Dipl.-Chem. Dr. rer. nat. E. Frhr. v. Bad luck man,
Patent Attorneys, Munich 9, Schweigerstr. 2

Named as inventor:

John A ₁ . Murphy, Norwark, Conn. (V. St. A.)

Claimed priority:

V. St. v. America April 9, 1959

space arranged containers to reduce to a minimum.

Since the container due to expansion and contraction with temperature changes their dimensions change significantly, the containers in the hold should be supported so that unhindered movement between the containers and the ship structure are possible while at the same time Means are provided to keep the containers within the insulated cargo space even when ramming and To fix rolling movements of the ship in their position. According to the older proposals listed above are for this purpose wedges and wedge tracks or grooves on the bottom and top of the container as well as provided on the ship's construction.

The inside of the container is for filling and emptying, for discharging vapors, for regulation the level of the liquid and the like. Accessible via a shaft of smaller dimensions, the extends upwardly from the top of the container through an opening in the deck of the ship. All of the inlet and outlet pipes, pressure regulating means, steam outlets and the like extend from this shaft into the container.

In these embodiments, many components are temperature changes during use exposed to the ambient temperatures prevailing during installation of about 28 to about 38 ° C, d. H. when the containers are empty, up

509 736/197

vary approximately -160 ° C when the containers are filled with liquid and have cooled down. When the outlet pipe extends down through the duct to the bottom of the container and the Pump placed on the sump, therefore, numerous parts of the pump are exposed to extreme temperature changes exposed so that expansion or contraction of the material to jamming moving parts or freezing of the pump. With such disturbances, the Liquid is completely removed from the container and the container can be heated to the point in question To be able to repair parts.

In the event that the main feed pump freezes or becomes inoperative for other reasons, a blower housing pump must be available at the bottom of the container, with the help of which the liquid is removed in a time-consuming manipulation. To do this, the pressure is changed alternately, to displace liquid, whereby the pressure is released again in each case, so that the liquid can flow into the blower housing.

It is also obvious that when a manhole is constructed, its dimensions are smaller are as those of the container, only limited space is available inside of which the various connections and welding work can be made, whereby the costs increase and the production of perfect welded joints is hindered.

In contrast, a ship is used to store and transport liquefied gases at around atmospheric pressure and low temperature, containing a rigid shell, the inner surface of which with a heat-insulating material is provided, which in turn has a tank arranged therein with a central, surrounding hollow, insulated, rigid column, which is rigidly connected to the tank walls, as a support serves for the tank and extends beyond the tank bottom and the tank top, according to the invention characterized by the fact that the closed one striving out above the tank ceiling Part of the tubular column has a manhole that the inner pipe surface with a heat-insulating Material is lined - and that at the level of the tank bottom or near the same within the column a pump is arranged, which is via a line at the level of the tank bottom or near the same, with the interior of the tank and via a line passed through the column with the free one Deck communicates.

In an expedient embodiment, in which the tank from a bottom layer of the heat-insulating. the material located on the bottom of the rigid outer shell extends the closed bottom part of the column goes down through the bottom of the tank and engages tightly into one Wedge guide in the layer of heat insulating material that is on the bottom of the rigid outer shell is located.

The pump can be in the bottom portion of the hollow column below the level of the bottom of the tank be arranged.

Even if the invention in the following using the example of the storage and transport of liquefied Natural gas is described, it can easily be compared to that of other liquefied gases adapt to the occurring conditions. Other such gases are ethane, ethylene, and propane Propylene.

For ships with such containers, a heat insulating material such as balsa wood is generally used. used, which completely or substantially completely surrounds the container. The containers can be used individually or together with other similar or different containers which will be discussed in more detail below. The ships are particularly suitable for overseas transport of liquefied gases, such as methane, which in the liquid state has a temperature of about -160 ° C.

The invention is explained in more detail below using an exemplary embodiment.

In Fig. Fig. 1 is a side view, partly in longitudinal section, of a ship with an outer hull 12 and 12 an inner sleeve 14 is shown, the latter being offset somewhat inwardly with respect to the outer sleeve, however, is connected to the outer shell, so that there is a rigid structure within which there is an open space 16 which can be divided into tanks for ballast water. Through the A heat exchange medium can also be routed to the transition from cold to the interspace to prevent outer shell.

The hold inside the inner hull is provided by extending transversely to the ship's longitudinal axis Partition walls 18 divided into individual rooms, the inner surfaces of which with a relatively thick layer 20 one heat insulating material e.g. B. balsa wood or quippo are occupied. In these isolated holds one or more containers 22, each with a column 34, are arranged. The liquid container consists made of aluminum, stainless steel or a metal whose strength even at the temperatures liquefied gases is sufficient. The inner and outer hulls 14 of the ship can be made of ordinary Be made of steel, but it is preferably made of a sufficient at low temperatures resistant material, so that if a container 22 is leaked as a secondary container can serve.

The containers 22 can have a cylindrical, but preferably a prismatic cross-section, so z. B. have a square or rectangular cross-section. They are also suitable for that Storage of liquefied gas on land.

In Fig. 2 and 3, the same reference numerals as in FIG. 1 are used for identical parts. You explain the construction and arrangement of a container the dimensions of which are such that it can accommodate a large amount of liquid 24. The one with round, square, rectangular, triangular or otherwise prismatic cross-sectional shape formed container has a top wall 28, a lower wall 30 and side walls 32 which are connected to one another in a gas-tight manner. The in A column 34, preferably located downwardly of the center access to the container, extends vertically downward in the form of a tubular member of cylindrical or polygonal cross-section. the Column has a greater height than the part of the container used to hold the liquid, so that it protrudes a short distance over the upper and lower container wall and a lower extension 36 and an upper extension 38 forms. The cross section of the column is chosen so that

There is enough room to provide access for workers and equipment to the lower end of the Pillar to create. The walls 40 of the column are made of a metal similar to that of the container walls 28, 30 and 32, and the walls of the column are matched with the adjacent container walls Way, e.g. B. by welding, tightly connected to the inside of the column from the liquid to be kept separate in the container.

The inner surface of the column is covered with a layer of insulating material 42 around the To reduce the transfer of heat or cold to a minimum, so as little as possible Heat enters the liquid and the inside of the column can be heated when people enter the Get in the column and have to work there. It can be seen that on the walls of the column im Compared to the rest of the walls of the hold, considerably less insulation material needs to be installed needs because it will very rarely be necessary to enter the column, and on that occasion warm air can be circulated inside the column. The pump 44 for displacement the liquid from the container is located within the column and preferably close to its bottom. The drive 46 z. B., in the form of an electric motor or a turbine, can be near the Pump may be provided. A line 48 connects the inlet of the pump to the outlet port 50 at Bottom of the liquid space of the container to allow the liquid from the container to the pump can flow. The line is provided with a flexible intermediate piece 52 so that it can move in response to changes in temperature can expand and contract. It can also be equipped with a valve 54 which can be opened and closed with the help of a remote control. The outlet of the Pump is in communication with a pipe for dispensing liquid from the container the line 56 which extends from the pump up through the column to above the liquid space. From there, the Continue piping through the top of the column, but it is preferred to have the delivery piping through pass the side wall of the column at a point where the container is protected by the insulation 58 is. Correspondingly, many of the lines that previously ran along the shaft can now have been laid below, can be passed through the column in order to move from this in a lateral direction to be led out through the column wall into the liquid space of the container. The top of the column is provided with a manhole 60. The parts 38 and 36 of the column can serve to fix the container within the isolated space.

The portion 36 of the column which extends downwardly beyond the lower wall 30 of the container, can act as a wedge that is received by a wedge guide 62 which is in the Container-carrying insulating bottom 26 is provided, the guide wedge and the receiving opening determine the stable position of the container, but allow the outer parts of the container to to shift towards and away from the guide when temperature changes cause expansion and cause contraction movements.

The part 38 of the column protruding upward beyond the upper container wall can be carried out in a similar manner act as a guide member extending from a guide opening 64 in the upper insulating wall or in another bracket is received so as to stabilize the position of the upper end of the container. The part of the extension 38 to be received by the guide opening 64 is dimensioned in such a way that that its length is greater than the theoretical value for the contraction that occurs, when the temperature of the container is decreased from about 38 ° C to about -160 ° C. Consequently the container can move freely in a vertical direction with respect to the ship's structure expand or contract without the guide portion disengaging from the guide comes, which enables independent movements of the container in all directions, when there is an expansion or contraction.

he follows.

The inside of the insulated column will normally be at a significantly higher temperature than the liquid in the container. If there are operational difficulties, you can Remove the pump from the unit without first having to remove all of the liquid remove from the container. It is also possible to keep the column at one temperature in the event of malfunctions hold where workers can make repairs inside the column; to this This avoids significant delays that would result from the liquid would have to be removed from the container first.

By extending the column downward beyond the bottom 30 of the container, it is possible to the inlet of the pump on one lying below the liquid in the container To arrange level, so that the liquid can be practically completely withdrawn from the container can. This enables the container to be used for other purposes during the return journey, d. H. no charge is lost and no time is needed for the liquefied to be completely removed Gas to be used. In addition, the arrangement according to the invention enables remove the liquid from the container as much as previously using it the bladder case pump was not possible. As most of the connections of the liquid receiving space the container can be moved through the column to the top of the container, one can see the number of pipelines (not shown here) that have run through the shaft of the Extend the container upwards, as well as significantly reduce the number of welds, thereby reducing simplifies the construction of the container and contributes to the manufacture of a stronger and better container low cost. These additional pipelines, not shown here, can Inlet pipe for filling the containers, pipes for removing vapors from the containers and the like.

It is not necessary to use a column 40 according to FIG. 3 to be provided in each individual container. It It is sufficient if only one or two of the containers arranged within an insulated cargo space are included a column construction of the type described are provided. In such cases, the

on the adjacent container according to FIG. 2 connected to one another by pipes or channels 70 be equipped with remotely controlled valves 72 so that the flow of liquid in a container or out of a container, a regulation of the liquid level in neighboring Containers, effected; thus can of one or more equipped with a column 40 according to the invention Containers from all containers can be emptied or filled.

The centrally arranged column contributes to a considerable extent to increasing the strength of the Container at, so that you can construct containers with an even larger capacity. The pillar can also be used as a support for stiffeners as shown in FIG. 3 as horizontal extending beams or plates 74 are shown. They are with the walls of the container and the Column preferably connected at vertical intervals.

To counteract the rocking of the container caused by stomping and rolling movements, you can buffers or stabilizers known per se, e.g. B. on the upper part of the container, arrange. In the case of the in FIG. 3 are coil springs for this purpose 80 are provided, the outer ends of which are fastened to a bracket 82.

The column can also be offset with respect to the central axis of the container. However, the column determines if it serves as a guide for the container, also its stable position, opposite which the expand or contract the outer parts of the container.

Claims (3)

Patent claims: 1. Ship for storing and transporting liquefied gases at around atmospheric pressure and low temperature, containing a rigid shell, 35 whose inner surface is provided with a heat-insulating material, which in turn surrounds a tank arranged therein with a central, hollow, insulated, rigid column which is rigidly connected to the tank walls, serves as a support for the tank and extends over the tank bottom and the The tank ceiling extends out, characterized in that the closed part (36) of the tubular column (40) protruding above the tank ceiling (28) has a manhole (60), that the inner pipe surface is lined with a heat-insulating material (42), and that at the level of the tank bottom (30) or close to it within the column (40) a pump (44) is arranged, which via a line (48) at the level of the tank bottom (30) or close to it, with the interior of the tank ( 22) and is in communication with the free deck via a line (56) guided through the column (40). 2. Ship according to claim 1, characterized. shows that the bottom with the tank bottom (30) connected and also extending closed bottom part (36) of the column (40) tightly engages a wedge guide (62) in the layer of heat insulating material (26) with which the bottom of the rigid outer shell (14) is provided., 3. Ship according to claim 2, characterized in that the pump (44) in the bottom part (36) the column (40), below the level of the tank bottom (30) is arranged. Considered publications:
German Patent No. 966 655;
French Patent No. 847 844;
Belgian Patent No. 557,263;
British Patent No. 801,507;
U.S. Patent No. 2,061,013. 1 sheet of drawings 509 539/41 4.65 Q Bundesdruckerei Berlin