WO1997026205A2

WO1997026205A2 - Safety casings for fluid containers

Info

Publication number: WO1997026205A2
Application number: PCT/DE1997/000005
Authority: WO
Inventors: Mirco Winde; Patrick RÖGLIN
Original assignee: Mirco Winde; Roeglin Patrick
Priority date: 1996-01-17
Filing date: 1997-01-02
Publication date: 1997-07-24
Also published as: AU1922397A; WO1997026205A3

Abstract

The invention concerns a casing having a plurality of superimposed layers for fluid containers, in particular for containers for flammable liquids or gases, preferably for fuel containers. In order to provide a fluid container casing which has improved properties with respect to the prior art, withstands high mechanical loads and prevents the container contents from emerging and being discharged into the environment if the container is damaged, the casing comprises at least one shock-absorbing layer and at least one fluid-adsorbing layer.

Description

Safety casing for fluid containers

The present invention relates to a casing with a plurality of layers arranged one above the other for fluid containers, in particular for containers for flammable liquids or gases, preferably for fuel containers.

Examples of jackets for safety containers for the storage and transport of dangerous liquids and gases are known from the prior art. The design and materials of such safety containers are dependent on the hazard potential arising from the liquids to be stored or transported. Safety container for the permanent storage of dangerous liquids, such as For example, heating oil tanks installed underground or above ground must meet different safety requirements than, for example, transport containers for tank trucks for fuels, aggressive chemicals or other liquid dangerous goods or fuel tanks for petrol or diesel fuels in cars.

Dangerous liquids include flammable or explosive liquids, such as gasoline or diesel fuels for internal combustion engines, heating oils and other heating fuels, highly flammable organic solvents, but also aggressive or toxic, inorganic or organic chemicals. The potential danger of such liquids in the event of an escape from the storage or transport container can on the one hand be the direct danger to people, buildings or vehicles due to fire, explosion, burns or poisoning, and on the other hand in a long-lasting, far-reaching pollution of the environment, such as e.g. Contamination or poisoning of groundwater and drinking water or plants.

Known protective containers for dangerous liquids, which are used primarily for the transport of such liquids, are intended to provide protection against the leakage of the liquid by protecting the container wall from mechanical external loads by means of a reinforcing jacket. The disadvantage of the known casings is that they can only protect the container from damage to a certain extent in the event of a transport accident or other force. The protection of the container essentially depends on the material and the thickness of the casing. With high safety requirements, high material costs and large thicknesses or volumes of the casing have to be accepted, which is why the safety containers currently used always represent a compromise between price, weight and size on the one hand and residual risk in the event of an accident on the other hand.

U.S. Patent 5,180,190 describes a damage-protected polyolefin container for transporting hazardous liquids in tankers. The protection of the tank container consists of a two-day sheathing of the container with a first layer of flexible polyurethane and a layer of stable fiber fabric arranged above it. In the event of a transport accident, the polyolefin container is protected from damage to a certain degree of mechanical stress. However, if the mechanical strength of the casing is exceeded, the tank contents can flow out unhindered and pose a great danger to people and the environment.

GB 2 01 5 952 describes a fuel tank with a self-sealing casing. The casing has a multilayer structure which contains a material which swells when it comes into contact with fuel. In the event of perforation of the container and fuel leakage, the swelling material is intended to seal the outlet opening.

EP 0.351 .137 describes a double-walled storage container for liquids with an inner container wall, an outer jacket and a porous fiber material arranged between them. The fiber material is needle-like and not woven and is made by a Binder, such as a liquid resin, held between the two container walls. The fibrous material, on the one hand in connection with the binder, has the task of filling the space between the container walls and thereby giving the walls support and structure, and on the other hand absorbing liquid escaping through holes in the inner wall of the container. Furthermore, the double-walled container with liquid sensors arranged in the fiber material and a display device which indicate the penetration of liquid from the inside of the container into the wall space. The container is intended and particularly suitable for stationary, underground fuel or heating tanks. Protection against extraordinary mechanical loads is not provided.

The utility model DE-GM 70 1 2 360 describes a fuel tank for motor vehicles with a two-day coating of open-cell foam material. The inner foam layer lying against the wall of the fuel tank is porous and stretchable and has a volume of at least 1/5 of the tank volume. The outer layer consists of a foam material that is tight and resistant to fuel. It consists of polyethylene or polyurethane foam and has a shock-absorbing function. The function of the inner layer is to absorb the fuel if it emerges from the container by evading the volume of the fuel due to its extensibility. Furthermore, the fuel can be distributed in the large pores of the inner layer if it escapes. A disadvantage of this two-layer container casing made of open-pore foam material is that it must have a very large volume and a very high thickness in order to provide the required absorption capacity for escaping fuel and sufficient mechanical protection in the event of an impact. Since the space utilization in modern motor vehicles, especially in passenger cars, is increasing, the volume and the thickness of such a safety casing for the fuel tank can only have a limited extent, which in turn means a compromise between safety and residual risk. Another disadvantage of the coating of the fuel tank described is that although it offers some protection against surface impact loads, sharp-edged parts, such as cracked or broken metal, can easily penetrate the foam material. In such a case, the fuel flows out of the container with a slight delay, but cannot be prevented since the leaking fuel is absorbed in the inner foam layer but is not retained. The leaking fuel can get into the environment despite the casing and can be ignited by subsequent sparking, carelessly thrown away cigarettes or the like and lead to dangerous injuries and burns to the people involved. Another disadvantage, especially the transport container from the prior art, is that in the event of slight perforations or corrosion damage to the container, a creeping leakage of the transported liquid can occur, which remains unnoticed by the user of the container over a longer period of time. In addition to the risk of fire or poisoning depending on the hazard potential of the transported liquid, the gradual leakage of dangerous liquids in any case leads to an unnoticed, possibly widely distributed environmental pollution.

The object of the invention is to provide a casing for fluid containers with improved properties compared to the prior art, which withstands both high mechanical stress and in the event of damage to the container prevents leakage and release of the contents in the container to the environment.

According to the invention, this object is achieved by a casing which has at least one shock-absorbing layer and at least one liquid-adsorbing layer.

The arrangement of at least one shock-absorbing layer in the sheathing has the advantage and the task of protecting the sheathed container from mechanical stresses when it falls down or when it hits an object. In the event of damage to the container wall due to external influences or corrosion, the liquid-adsorbing layer of the casing absorbs the liquid and holds it there for at least a longer period of time. Is the liquid in the container z. B. easily combustible, the liquid-adsorbing layer prevents the liquid from reaching the interior of the container into the environment and can be ignited. The adsorption continues to minimize gas formation in volatile liquids and thus the formation of explosive gas-air mixtures. Another advantage of the liquid adsorbing layer is that it also reduces the risk of damage to the container wall due to external mechanical loads due to its material properties. Thus, if the container contains gas or solids, the casing according to the invention is also suitable for such containers, even if the liquid-adsorbing layer cannot absorb these substances, but only has an additional shock-absorbing function. The container itself, which is protected by the casing, can be constructed from metal, plastic or any other suitable material. If the container is made entirely or partially of metal, the casing additionally protects against external corrosive influences.

The casing preferably additionally has at least one liquid-impermeable. stretchable layer and / or at least one liquid-impermeable, tear-resistant layer. In addition to the liquid-adsorbing layer, both layers prevent leakage of liquid or other fluids to the environment. This is particularly advantageous if, in the event of damage to the container wall, locally limited large quantities of liquid penetrate into the liquid-adsorbing layer and the adsorption capacity of the liquid-adsorbing layer is no longer sufficient at this point to absorb the large liquid volume. Liquid that strikes one of the two liquid-impermeable layers is distributed and can be adsorbed elsewhere. Furthermore, the liquid-impermeable layers protect the casing against the penetration of liquid from the outside and thus against saturation of the adsorption capacity of the liquid-adsorbing layer by foreign liquid. Another advantage of the liquid-impermeable, stretchable layer is that it yields to external mechanical loads and, in addition to the shock-absorbing layer, absorbs energy that would otherwise damage the container wall. The liquid-impermeable, tear-resistant layer additionally protects in the event of mechanical stress from e.g. B. an accident or falling of the container before the penetration of pointed or sharp-edged parts or the bursting of the casing.

In a preferred embodiment, the shock-absorbing layer is resistant to liquid, in particular combustible liquid, preferably gasoline, other fuels and / or aggressive chemicals. The shock-absorbing layer preferably has foam, particularly preferably polyethylene foam. In the case of a creeping liquid, this material has the advantage of not dissolving and losing its shock-absorbing properties. Polyethylene foam is particularly suitable for this, since it is very inexpensive to manufacture and has long-term resistance to a large number of organic solvents, petrochemical products and aggressive inorganic and organic chemicals.

In a further preferred embodiment of the invention, the liquid-adsorbing layer has a liquid-adsorbing, porous material, preferably a small-sized or granulated material. Porous, particularly small-pored materials have the advantage of having high adsorption capacities for liquids with a low weight and small volumes. As a result, the sheathing can be made so light and thin that its dimensions are acceptable for most applications and generally do not represent a compromise between safety and residual risk from escaping liquid. The use of small-scale or granulated adsorption material offers the advantage, on the one hand, that the layer thickness of the liquid-adsorbing layer is arbitrary depending on the application can be varied, and on the other hand, the fine-grained or granular material of the liquid-adsorbing layer provides an additional protective function against mechanical stress. Small-grained or granular material can be shifted laterally when impacted and thus absorb impact energy and, as a solid, offers additional protection against the penetration of the sheathing of pointed or sharp-edged parts. In the case of large quantities of liquid emerging locally from the inside of the container, small-scale or granulated material in the liquid-adsorbing layer has the advantage that the liquid quickly distributes itself into the adjacent areas in the liquid-adsorbing layer and thus the risk of escaping from the casing through an opening due to an Damage is reduced. Particularly suitable liquid-adsorbing materials are porous clay granules, such as those used for. B. in commercial form by the fire brigade to absorb leaking fuel after accidents, or clay granules, which are used as water-storing media for the supply of potted plants. The porous clay granulate Terraperl S from Brandschutz TOTAL has proven to be particularly suitable in the tests that led to this invention. It has a high specific adsorption capacity of approximately 1.5 ml of H-0 per gram of granules and a low specific weight of approximately 0.5 g / cm ^3. The volume of this clay granulate required in the liquid-adsorbing layer is therefore low in relation to the volume of the container , and the thickness and weight of the sheath can be kept to an acceptable level.

It is further preferred if the liquid-impermeable, stretchable layer and / or the liquid-impermeable, tear-resistant layer have an elastic polymer material or rubber. Polymer materials which can be applied in liquid form to an underlying layer and which obtain their desired properties after polymerization have proven to be particularly suitable. For example, the product Mowilith (V) DM 1 340, which is available in liquid form, has proven to be a particularly stretchable polymer material, and the polymerized product Mowilith LDM 1880, both from Hoechst AG, has proven to be extremely tear-resistant. Both materials can be applied by painting or dipping in any layer thickness and polymerize independently by drying in air, whereby their weight is reduced by half compared to the liquid form. However, the polymer material or rubber can also be in polymerized form, e.g. B. as webs, are used.

In a preferred embodiment of the invention, the innermost layer of the casing adjoining the outer wall of a liquid container is the wall of the container partially or fully connected, preferably glued. It is also advantageous if at least two adjoining layers of the sheathing are connected to one another in partial areas or over the full area, preferably glued. As a result, the overall stability of the casing and the liquid container is significantly increased. Any adhesive suitable for the corresponding materials can be used as the compound. The connection of the layers to one another or to the outer wall of the liquid container in partial areas or over the entire surface prevents displacement of the layers against one another or against the outer wall of the liquid container and increases the integral stability of the entire system.

In a further embodiment of the invention, the liquid-adsorbing layer has chambers in which the liquid-adsorbing material is arranged. An embodiment in which the liquid-adsorbing material is arranged or sewn in liquid-permeable holding devices, preferably made of fabric, has proven to be particularly advantageous. For this purpose, for example, two fabric webs one above the other can be provided with seams which delimit chambers between the fabric webs in which the liquid-adsorbing material is arranged. The advantage of arranging the liquid-adsorbing material in chambers is that the liquid-adsorbing material arranged in the casing above or to the side of a liquid container does not become over time due to vibrations or simply due to the force of gravity in the section arranged below the liquid container Sheath can move. However, simple room dividers can also be arranged as holding devices in the liquid-adsorbing layer, or commercially available lamella networks can be used. Also suitable are materials such as those used, for example, for the manufacture of baby diapers or sanitary napkins that absorb liquids or allow them to pass in a preferred direction.

It has also proven to be particularly expedient to glue or otherwise secure the liquid-adsorbing material on a carrier layer. In this case, no space dividers are required in the liquid adsorbent layer which prevent the adsorbent material from moving within the jacket.

In a particularly advantageous embodiment of the invention, the casing, starting from the innermost layer

a) a shock-absorbing layer, b) a liquid-absorbing layer, c) a shock-absorbing layer and d) a liquid-impermeable, tear-resistant or stretchable layer or both arranged one above the other

on. Depending on the field of application, further liquid-adsorbing and shock-absorbing layers are arranged in further embodiments between the shock-absorbing layer and the liquid-impermeable layer. However, any other arrangement of the different layers is also possible, although at least one liquid-impermeable layer should not necessarily be arranged directly on, but at least always above, the outermost liquid-adsorbing layer, in order to achieve the above-mentioned advantages of the liquid sealing of the casing to the outside.

It is furthermore particularly advantageous to arrange at least one further layer, preferably a metallic coating or plastic coating, over the outermost liquid-impermeable layer of the casing. The metallic coating can be an aluminum coating, preferably vapor-deposited aluminum. As a result, the layers of the sheathing made of polymer material or rubber are protected against light and ionizing radiation for long periods of time and are prevented from drying out and becoming brittle. Furthermore, the metallic coating protects the casing and the liquid container underneath in the event of a fire from overheating too quickly, which can significantly reduce the risk of explosion for fuel tanks.

In addition to heat shielding, the entire jacket also offers protection against cold from the outside, which is important when storing liquids that are sensitive to cold, e.g. As diesel fuel or heating oil, is of great benefit.

In a further advantageous embodiment of the invention, electronic liquid sensors, preferably sensors for gasoline or other fuels, are arranged on the outside, the inside or in the layers of the casing. Appropriate gas sensors can be used for jackets for gas containers. The sensors are connected to a display module for the optical and / or acoustic display in order to display liquid that has escaped from the container and has been detected by the sensors. The sensors can be arranged, for example, directly on the outer container wall or in one of the layers, preferably in the liquid-adsorbing layer, of the casing. In the event of a liquid leak, the user of the liquid container is immediately over informed of this process and he can take appropriate security measures. The sensor system in conjunction with the electronic display module is particularly useful when there is a creeping liquid or gas leak, e.g. B. due to corrosion damage to the container, advantageous, since such creeping exits, in contrast to liquid keitsauslassen from tanks in serious accidents, are usually not noticed immediately. Greater risks to people and the environment can be avoided by timely detection of an exit.

If the casing according to the invention is used to protect fuel tanks for cars or other motor vehicles, it is particularly advantageous to arrange sensors both near the bottom and the top of the container. Accident victims or helpers are immediately warned when fuel leaks, regardless of whether the vehicle is in a normal position or in an upside-down position after the vehicle has overturned. Sensors that register escaping fuel both in liquid form and as a gas are particularly suitable.

The electronic display module can be constructed in such a way that it indicates the escape of liquid or gas from the interior of the container both optically by lighting or blinking of a lamp or light-emitting diode and by a signal tone. Furthermore, it is advantageous if the display module is a device such as. B. has a light emitting diode, which signals the operational readiness of the device.

The casing according to the present invention can expediently also be designed as a reusable transport device for liquid, gas or solid containers or as part of such a device. The casing according to the invention is suitable, for example, as security packaging for shipping dangerous goods containers in the chemical industry, such as pressure or liquefied gas bottles. So far, the dispatch of such goods has required a high level of packaging with voluminous, often non-reusable packaging material. By using the casing according to the invention for shipping such goods, material, volume, weight and thereby postage and other costs can be saved. Depending on the goods to be transported, it is expedient to design the casing as a bag with a closure device. For example, snap closures of any kind, but also Velcro straps, can be used as closure devices. A closure device has proven to be particularly suitable in which the edges are placed against one another at the bag opening and rolled up in the direction of the bag to such an extent that the container to be transported is seated firmly and without play in the casing. The rolled-up part of the bag is then placed on the outside of the bag and fixed with a snap or Velcro fastener. This results in a space-saving closure option in which liquid is prevented from escaping or penetrating through the opening of the bag.

Further advantages, features and possible uses of the present invention will become clear from the following description of preferred embodiments and the associated figures.

FIG. 1 is a schematic illustration of a liquid container with a casing according to the invention, sensors and display module,

Figure 2 is a schematic cross section through a portion of the shroud

Figure 1,

FIG. 1 shows a liquid container 10 designed as a fuel tank for a motor vehicle with a container wall 1 made of plastic or metal and a casing 12 according to the invention surrounding the container wall. The casing is composed of a first shock-absorbing layer 2, which rests on the container wall 1, a liquid-adsorbing layer Layer 3, a second shock-absorbing layer 4, a liquid-impermeable, stretchable layer 5, a liquid-impermeable, tear-resistant layer 6 and an aluminum coating 7. The shock-absorbing layers 2 and 4 consist of polyethylene foam, the first shock-absorbing layer 2 with the container wall is glued. The liquid-adsorbing layer 3 contains a gas-adsorbing clay granulate in the form of irregular spheres. The liquid-impermeable, stretchable or tear-resistant layers 5 or 6 consist of the elastic polymer material Mowilith (V) DM 1340 or Mowilith LDM 1880. The outermost layer 7 is a vapor-deposited aluminum coating which protects the layers below from light, heat and before drying out protects. Furthermore, FIG. 1 shows the arrangement of two sensors 8 and 8 ', which are arranged in the casing 12 near the top and bottom of the liquid container and are connected to a display module 9. The display module 9 is equipped with two light-emitting diodes 9 ′ and 9 ″, which indicate the readiness for operation of the display module or liquid emerging from the container and detected by the sensors.

Figure 2 shows in cross section the container wall 1 and the overlying casing 1 2 from Figure 1. The sequence and numbering of the individual layers arranged one above the other corresponds to that from FIG. 1. The diameters of the individual layers 2 to 7 and the container wall 1 are only shown by way of example in FIG. 2, but can vary depending on the application and requirement deviate from it.

Claims

Patent claims

1 . Sheath (12) with a plurality of layers for fluid containers (10) arranged one above the other, in particular for containers for flammable liquids or gases, preferably for fuel containers, characterized in that the sheath (1 2) has at least one shock-absorbing layer (2, 4) and at least has a liquid-adsorbing layer (3).

2. Sheath according to claim 1, characterized in that in addition at least one liquid-impermeable, stretchable layer (5) and / or additionally at least one liquid-impermeable, tear-resistant layer (6) is provided.

3. Sheath according to one of claims 1 or 2, characterized in that the shock-absorbing layer (2, 4) is resistant to liquid, in particular flammable liquid, preferably gasoline, other fuels and / or aggressive chemicals, and preferably foam, preferably polyethylene. Foam.

4. Sheath according to one of claims 1 to 3, characterized in that the liquid-adsorbing (3) layer has a liquid-adsorbing, porous material, preferably a small-sized or granular material.

5. Sheath according to one of claims 1 to 4, characterized in that the liquid-adsorbing layer (3) has a porous clay granulate.

6. Sheath according to one of claims 2 to 5, characterized in that the liquid-impermeable, stretchable layer (5) has an elastic polymer material or rubber.

7. Sheath according to one of claims 2 to 6, characterized in that the liquid-impermeable, tear-resistant layer (6) comprises an elastic polymer material or rubber.

8. Sheath according to one of claims 1 to 7, characterized in that the innermost layer (2) adjacent to the outer wall (1) of a liquid container Sheathing (12) is connected to the wall (1) in partial areas or over the entire surface, preferably is glued.

9. Sheathing according to one of claims 1 to 8, characterized in that at least two adjacent layers of the sheath (12) are connected to one another in partial areas or over the full area, preferably glued.

10. Sheath according to one of claims 1 to 9, characterized in that the liquid-adsorbing layer (3) has chambers in which the liquid-adsorbing material is arranged.

1 1. Sheathing according to one of claims 1 to 10, characterized in that the liquid-adsorbing layer (3) has liquid-permeable holding devices, preferably made of fabric, in which the liquid-adsorbing material is arranged or sewn.

12. Sheath according to one of claims 1 to 1 1, characterized in that the liquid-adsorbing material is fastened to a carrier layer, preferably is glued on.

13. Sheathing according to one of claims 1 to 12, characterized in that starting from the innermost layer a) a shock-absorbing layer (2), b) a liquid-adsorbing layer (3), c) a shock-absorbing layer (4) and d) has a liquid-impermeable, tear-resistant (6) or stretchable (5) layer or both arranged one above the other.

14. Sheath according to claim 13, characterized in that between the shock-absorbing layer (4) and the liquid-impermeable layer (5, 6) further liquid-absorbing and shock-absorbing layers are arranged.

1 5. Sheath according to one of claims 13 or 14, characterized in that at least one further layer (7), preferably a metallic coating or a plastic coating, is arranged over the outermost liquid-impermeable layer (6).

16. Sheath according to claim 15, characterized in that the metallic coating (7) contains aluminum, preferably vapor-deposited aluminum.

17. Sheath according to one of claims 1 to 1 6, characterized in that electronic liquid sensors (8), preferably sensors for gasoline or other fuels, are provided on the outside, on the inside or in the layers of the casing.

18. Sheath according to claim 17, characterized in that the liquid sensors (8) are arranged in the vicinity of the bottom or top of a jacketed container (10).

19. Sheath according to one of claims 17 or 18, characterized in that an electronic display module (9) for the optical and / or acoustic display of leaked from a jacketed container (10) and by the sensors (8) detected liquid with the sensors connected is .

20. Sheath according to one of claims 1 to 19, characterized in that it is designed as a reusable transport device for liquid, gas or solids containers or is part of such a device.

21. Sheath according to one of claims 1 to 20, characterized in that it is designed as a bag with a closure device, preferably a snap, Velcro or roll closure.

22. Fluid container, in particular container for flammable liquids or gases, preferably fuel container, characterized in that it identifies a casing according to one of claims 1 to 21.