DE102024000206A1 - Device for leak detection on containers and pipelines for the collection and storage of water-polluting liquids - Google Patents

Abstract

Device for leak detection in containers for the reception and storage of liquids which are generally hazardous to water, characterized in that in a container (1) to be monitored, an electrically conductive layer (3) is arranged on the inside of the container wall and the container base, that an electrically insulating layer (4) is arranged between the container contents (2) and the electrically conductive layer (3), and that at least one electrode (5) which is connected to an externally arranged evaluation unit is arranged in the container contents (2).

Description

The invention relates to a device for leak detection in containers for the reception and storage of water-polluting liquids.

According to the Ordinance on Facilities for Handling Substances Hazardous to Water (AwSV), which came into force in 2017, it is necessary for containers with such contents and a size of 25m³ ^{or more} to be equipped with leak detection for substances hazardous to water in water classes 1-3 and generally hazardous to water.

State-of-the-art leak detection devices include visual methods, such as optical inspection by an inspector or container level measurement. These are highly inaccurate and depend heavily on the inspector's experience and the consideration of ambient conditions.

In the DE 20 2018 000 073 U1 A monitoring system based on an electronic measuring principle has already been demonstrated, whereby electrical measuring probes are placed around and beneath the container, distributed in the floor, and an electrical probe is also placed in the liquid in the container's contents. Both probes measure the electrical conductivity of the respective media at specified intervals and compare them with each other. This method is very complex to evaluate and is subject to significant interference from environmental influences, resulting in a certain degree of unreliability.

For this reason, the above-mentioned methods are very poorly accepted by the operators of such containers and systems.

Common containers for the collection and storage of water-polluting liquids, such as liquid manure, slurry, and/or silage leachate, or other water-polluting liquids, are made of concrete or foil-lined earth basins. The conductivity of concrete and typical soils varies greatly depending on their composition and water content, making electrical leak detection difficult and leading to inconclusive results.

The object of the invention is therefore to create a reliable method for detecting leaks in containers used for the containment and storage of water-polluting, electrically conductive liquids, which can also be retrofitted into existing containers and is straightforward to evaluate. It should function reliably regardless of environmental factors.

According to this, a device for leak detection in containers for the reception and storage of water-polluting liquids initially consists of an electrically conductive layer which is arranged on the inside of the container wall and the container contents to be monitored. An electrically insulating layer is arranged between the container contents and the electrically conductive layer, and at least one electrode is arranged in the container contents, which is connected to an externally arranged evaluation unit. Electric current is used as the test medium. A voltage is applied to the electrically conductive layer. If the insulating layer is damaged, an electrical circuit is formed and thus current flows. This allows the conclusion that there is a leak in the insulating layer. A breakdown occurs.

A prerequisite for the use of this device is that the container is also electrically insulated. The arrangement of the insulating layer within the container makes it suitable for any container, as the insulating layer shields it from the conductive liquid in the container's contents. This also allows its use with steel containers.

A further advantage is that both the conductive layer and the insulating layer can be subsequently incorporated into existing containers in order to monitor the safe testing of the container's tightness.

It has proven advantageous for the electrically conductive layer to be designed as a durable, electrically conductive film, composite film, and/or composite material. These films can also be equipped with a self-adhesive feature to allow for quick and easy integration and placement of the film in the container.

The conductive layer can also be designed as an electrically conductive filler and applied to the inside of the container wall. This creates a permanent conductive coating on the inside of the container wall. The filler contains electrically conductive components that, if the insulation layer leaks, generate a short circuit through the electrical voltage applied to the container liquid, thus indicating that there is a leak in the insulation layer.

It is also possible for the electrically conductive layer to be formed as electrically conductive concrete, which is applied as an internal coating to the inner wall of the container. The concrete mass also contains electrically conductive Components are integrated that create a closed circuit when an electrical voltage is applied to the container fluid if the insulation layer leaks. The resulting short circuit indicates that there is a leak in the insulation layer. If no closed circuit is created, the insulation film and thus the container are sealed.

The electrically integrated components in the concrete can be replaced by the metal reinforcement in the concrete or their conductivity can be enhanced. It is also possible to integrate wire mesh, which can replace the conductive components in the concrete and/or enhance their electrical conductivity.

Forming the electrically insulating layer as a flexible, non-conductive, durable, and diffusion-tight plastic film has proven advantageous. However, the use of a flexible, non-conductive, durable, and diffusion-tight textile fabric or fleece is also possible. It is important that the insulating layer does not allow vapor or moisture to pass through to ensure the electrical insulation of the liquid.

The liquid itself must be electrically conductive. This is the case with liquid manure, slurry, and silage leachate, so that when voltage is applied and a leak occurs in the insulating layer, a closed circuit is created, indicating a short circuit. Electrically speaking, this is salt water (an aqueous solution with ions), which is electrically conductive. An improved measurement is achieved with a 4-pole arrangement, in which two electrodes are used for the current input and the other two electrodes for voltage measurement. The two voltage electrodes form a movable dipole, and the surface voltage distribution is observed. If there is a leak in the insulating layer, this can be identified as a characteristic change in the voltage sign.

Before commissioning a leak detection device, the insulation layer is checked for leaks. An electrical voltage is applied to the conductive layer. The electrode, which is normally located inside the container, is exposed to a film of liquid and held in the empty interior of the container. In the event of a leak in the insulation layer, the film of water would create a closed electrical circuit and thus indicate the leak.

It is therefore a very simple, easy-to-retrofit, and cost-effective method for detecting leaks in a container containing water-polluting contents. This can reliably prevent the release of such liquids from the container area into the environment.

A further advantage is the use of this device for all types of containers, including foil-lined earth basins.

The invention will be explained in more detail using exemplary embodiments.

• 1 eine schematische Schnittdarstellung eines Güllebehälters 1 mit einer gesonderten elektrisch leitfähigen Schicht 3 und einer darüber angeordneten elektrisch isolierenden Schicht 4,
• 2 eine schematische Schnittdarstellung eines Güllebehälters 1 mit einer als elektrisch leitfähigen Schicht 3 ausgebildeten Behälterwand und einer darüber angeordneten elektrisch isolierenden Schicht 4,
• 3 eine schematische Schnittdarstellung eines Güllebehälters 1 mit einer in der Behälterwand 3 integrierten elektrisch leitfähigen Schicht 3 und einer darüber angeordneten elektrisch isolierenden Schicht 4 und
• 4 eine schematische Querschnittdarstellung eines Rohrleitungsabschnittes mit einer

The attached drawings show:

• 1 a schematic sectional view of a slurry tank 1 with a separate electrically conductive layer 3 and an electrically insulating layer 4 arranged above it,
• 2 a schematic sectional view of a slurry tank 1 with a tank wall designed as an electrically conductive layer 3 and an electrically insulating layer 4 arranged above it,
• 3 a schematic sectional view of a slurry tank 1 with an electrically conductive layer 3 integrated in the tank wall 3 and an electrically insulating layer 4 arranged above it and
• 4 a schematic cross-sectional view of a pipeline section with a

Example 1:

According to the 1 A device for leak detection on containers for the reception and storage of liquids that are generally hazardous to water consists of an electrically conductive layer 3, which is arranged in a container 1 to be monitored on the inside of the container wall and the container base in such a way that it completely covers the interior of the container. The electrically conductive layer 3 is designed as an electrically conductive, durable film in such a way that individual layers are reliably connected to one another by means of welded joints and, due to the nature of the film and the welded connection of the film, form a circumferential, water-permeable membrane that seals the interior of the container from the container wall. An electrically insulating layer 4 is arranged above this electrically conductive layer 3, between the container contents 2 and the electrically conductive layer 3, in such a way that it also completely covers and covers the interior of the container with the electrically conductive layer 3. This electrically insulating layer 4 is a flexible, non-conductive, durable and diffusion-tight plastic film.

The individual strips are also reliably connected to one another by means of suitable welds, thus forming a circumferential, water-proof membrane that seals the container interior from the container wall. At least one electrode 5 is arranged in the container contents 2, which is connected to an externally arranged evaluation unit. An electrical voltage is applied to the electrode 5 at regular intervals, and the evaluation unit indicates whether or not an electric shock has occurred.

This leak detection device for container 1 provides an effective way to quickly and clearly identify a leak.

When a voltage is applied to electrode 5, nothing happens if there is no leakage in the electrically insulating layer. However, if there is a leak in the electrically insulating layer 4, an electrical short circuit occurs when a voltage is applied to electrode 5, as the liquid reaches the electrically conductive layer through the leak.

Example 2:

According to the 2 The device according to the invention for leak detection on containers for receiving and storing water-polluting liquids consists of an electrically conductive layer 3, wherein the inner surfaces of the container wall and the container base are each formed from an electrically conductive concrete, thus forming the electrically conductive layer 3. However, the electrically conductive layer 3 can also be formed from an electrically conductive filler.

This electrically conductive concrete is sealed to the interior of the container 1 with an electrically insulating layer 4 in such a way that it completely encloses and covers the container interior with the electrically conductive layer 3. This electrically insulating layer 4 is a flexible, non-conductive, durable, and diffusion-tight plastic film.

Example 3:

According to the 3 The device according to the invention for leak detection in containers for the reception and storage of water-polluting liquids consists of an electrically conductive layer 3, which is formed inside the concrete wall and simultaneously serves as an electrically conductive reinforcement. This can, on the one hand, support the stability of the concrete wall and, on the other hand, ensure electrical conductivity.

The reinforcement can be designed as a wire mesh that runs seamlessly through the concrete to form the tank wall and the tank bottom.

The interior of the container 1 is provided with an additional electrically insulating layer covering it.

Example 4:

According to the 4 A device according to the invention for leak detection in pipelines for the passage and transport of liquids that are generally hazardous to water is designed such that an electrically conductive layer is arranged on the inside of the pipe wall in a pipeline section 6 to be monitored, based on its length, wherein the electrically conductive layer 3 is arranged on the entire inner wall of the pipeline section 6. An electrically insulating layer 4 is arranged between the pipe contents 7 and the electrically conductive layer 3 such that the entire interior of the pipe section 6 is also lined therewith. The electrically insulating layer 4 is designed as a flexible, non-conductive, durable and diffusion-tight textile fabric. At least in the area of the bottom and always in the area of the pipe contents 7, at least one electrode 5, which is connected to an externally arranged evaluation unit, is arranged. This ensures that when an electrical voltage is applied to the electrode 5, it can be indicated whether or not there is a leakage that would initiate the current flow.

All of the examples presented here demonstrate a fast, continuous, and reliable way to monitor leaks in containers or pipelines that store or transport liquids that are generally hazardous to water, at specified intervals. A further advantage of these variants is that they can all be retrofitted to existing containers and pipelines.

List of reference symbols

1

container

2

Container contents

3

Electrically conductive layer

4

Electrically insulating layer

5

electrode

6

Pipeline section

7

Pipe contents

QUOTES CONTAINED IN THE DESCRIPTION

This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 20 2018 000 073 U1 [0004]

Claims (10)

Device for leak detection in containers for the reception and storage of liquids which are generally hazardous to water, characterized in that in a container (1) to be monitored, an electrically conductive layer (3) is arranged on the inside of the container wall and the container base, that an electrically insulating layer (4) is arranged between the container contents (2) and the electrically conductive layer (3), and that at least one electrode (5) which is connected to an externally arranged evaluation unit is arranged in the container contents (2). Device for leak detection in pipelines for the passage and transport of liquids which are generally hazardous to water, characterized in that an electrically conductive layer (3) is arranged on the inside of the pipe wall in a pipeline section (6) to be monitored, that an electrically insulating layer (4) is arranged between the pipe contents (7) and the electrically conductive layer (3), and that at least one electrode (5) which is connected to an externally arranged evaluation unit is arranged in the bottom region of the pipe contents (7). Device for leak detection on containers for the storage of water-polluting liquids according to Claims 1 and 2 , characterized in that the electrically conductive layer is designed as an electrically conductive, durable film. Device for leak detection on containers for the storage of water-polluting liquids according to Claims 1 and 2 , characterized in that the electrically conductive layer (3) is designed as an electrically conductive filler. Device for leak detection on containers for the storage of water-polluting liquids according to Claims 1 and 2 , characterized in that the electrically conductive layer (3) is formed as electrically conductive concrete. Device for leak detection on containers for the storage of water-polluting liquids according to Claim 5 , characterized in that the electrical conductivity of the concrete is formed by a reinforcement arranged in the concrete. Device for leak detection on containers for the storage of water-polluting liquids according to Claim 5 , characterized in that the electrical conductivity of the concrete is formed by a wire mesh arranged in the concrete. Device for leak detection on containers for holding water-polluting liquids according to one of the Claims 1 and 2 , characterized in that the electrically conductive layer (3) is formed and arranged as a wire mesh on the inside of the container or pipe wall and the electrically insulating layer is formed from a non-conductive concrete mass and is arranged above the electrically conductive layer (3). Device for leak detection on containers for holding water-polluting liquids according to one of the Claims 1 until 5 and 8 , characterized in that the electrically insulating layer (4) is a flexible, non-conductive, durable and diffusion-tight plastic film. Device for leak detection on containers for holding water-polluting liquids according to one of the Claims 1 until 5 , and 8, characterized in that the electrically insulating layer (4) is a flexible, non-conductive, hard-wearing and diffusion-tight textile fabric.