DE10256913B3 - Leakage monitoring device for vertical vessel wall of tank or silo for hazardous liquid detecting leakage liquid in collection space coupled to monitoring space between vessel inner and outer skins - Google Patents

Abstract

The leakage monitoring device detects a leak within a monitoring space (10.1,10.2) between an inner skin (9.1,9.2) and an outer skin (7.1,7.2) of the vessel wall, for activating an alarm. The lowest point of the monitoring space is coupled to a liquid-tight external collection space (11.1,11.2) for collection of the leakage liquid, containing a leakage detection probe (16) coupled to the monitoring device. A vent line (14) is positioned above the maximum filling level.

Description

The invention relates to a device for leakage monitoring on vertical vessel walls from at least one-shot standing tanks, containers and silos for storing liquids, especially water-endangering Liquids, with one between the inner and outer jacket the tank or container wall trained surveillance room, who with a monitoring device for Signal processing, storage and display of a leak in the monitoring room is in operative connection and means for triggering the alarm.

To protect against the escape of flammable, in particular groundwater-damaging, liquids from tanks, containers or silos as a result of leaks, it is known to either use the dangerous liquid in above-ground tank structures with a collecting cup ( DE 1 264 736 . DE 39 37 638 A1 ) or in double-walled underground containers or tanks ( DE 40 15 821 A1 . DE 41 27 090 A1 ) to store. The monitoring of the cavity formed between the inner and outer shell is then carried out by means of a vacuum monitoring device, which detects and displays a change in the vacuum in the cavity as a result of a leak.

The collecting cups of above-ground tank structures consist of regularly a reinforced concrete floor and a cylindrical one that projects upwards from it Sheet steel jacket. The collecting cups are very technical and expensive elaborate, require take up a lot of space and must be constantly checked for leaks become.

Double-walled vertical tank walls from above ground Tank structures consist of regularly several to tank jacket shots liquid-tight welded together Outer casing sheets, which represent the structural part of the tank structure. On the inside of the outer jacket there is a doubling by means of tear plates, smooth plates with Fabric liners or with spacers so that everyone can joined Tank jacket shot forms a separate monitoring room. Everyone of these surveillance rooms the one on top of the other arranged, welded Tank shell courses the entire tank structure requires separate vacuum monitoring, which is the total cost of raise the tank structure. To have to corresponding measuring lines to the individual monitoring rooms and to the measuring and evaluation center. These known vacuum monitoring devices enable the detection of a pressure loss, but cannot determine whether welded connections, Flanges, inner jacket or the outer jacket is leaking.

From the EP 0 705 773 B1 a storage tank with a single-walled tank jacket and double-jacket tank bottom is also known, the cavity of which is also checked by means of negative pressure monitoring, other known solutions for detecting leaks, for example on double-jacket tank floors ( DE 43 22 859 A1 . EP 0 633 460 A1 . DE 198 05 263 A1 . EP 0 251 045 A1 . US 3,721,898 . US 4,404,516 ) use sensor cables, which are either arranged directly in the monitoring room or routed around the tank jacket.

In the case of large tank containers such as tanks with a capacity of 10,000 to 100,000 m ³ , the positioning of sensor cables in the vertically extending cavity of the tank jacket leads to problems during the erection and assembly. Increases in temperature when welding the jacket sheets, mechanical effects when aligning the sheets, especially at the edge areas, have a negative effect on the sensitive sensor cables or probes.

A replacement of sensor cables is hardly possible or only with a disproportionately high effort, so that, for example, a changeover of the tank to another liquid storage item other electrical properties is not readily possible. It is also not possible to replace the defective sensors.

Furthermore, from the DE 296 21 536 U1 a cylindrical flat-bottom tank for the storage of flammable or water-polluting liquids is known, in which at least the cylindrical jacket has a double design, the two walls being at a small distance from the tank volume, and a vacuum is present in the monitoring space formed by the two walls and and liquid detection devices are monitored.

This is the state of the art the invention has for its object a device of the beginning to improve the type mentioned in such a way that precise leakage monitoring on double-walled vertical tank walls with little effort, high robustness and reliability, Maintenance and ease of use even with different ones bearing fluids possible is, an exchange of the sensor means depending on the type and properties the storage liquid guaranteed becomes.

This task is performed by a device genus mentioned at the outset with the characteristic features of the Claim 1 solved.

Advantageous embodiments of the The method and the device can be found in the subclaims.

The device according to the invention is characterized in that the leakage means, for example probes, for the detection of liquids are easily accessible from the outside, can be replaced in an assembly-friendly manner depending on the type and properties of the liquid stored goods, without complete emptying of the tank structure and removal the sensor technology becomes necessary. For this purpose, the leakage liquid is discharged from the monitoring room into a collecting room which is accessible from the outside and controlled by leakage probes and is detected there. Since such a simple detection space is assigned to each monitoring area of the tank jacket, the leakage location can be determined quickly, easily and simply.

The ease of maintenance and operation of the device according to the invention is well adapted to the conditions of rough tank operation.

The invention is intended to: an embodiment are explained in more detail.

In the accompanying drawing shows 1 a section through a vertical tank jacket of a fixed roof tank with the device according to the invention.

The device described comes in this embodiment with two-shot fixed roof tank 1 for use. The fixed roof tank 1 consists essentially of a cylindrical tank jacket 2 that from a first tank jacket shot 3 and a second tank jacket shot 4 is composed of the tank roof 5 wearing. The tank coat 2 is on a tank bottom not shown 6 placed. Every tank jacket shot 3 respectively. 4 has an outer jacket 7.1 respectively. 7.2 and one from the outer jacket 7.1 respectively. 7.2 by spacers 8th spaced inner jacket 9.1 respectively. 9.2 ,

Tank shell ring 3 and 4 are connected to each other by welding in a liquid-tight manner, the weld connection between the inner jacket 9.1 of the first tank jacket shot 3 and the inner jacket 9.2 of the tank jacket shot 3 is acted upon by the liquid against the direction of flow.

Between inner jacket 9.1 respectively. 9.2 and outer jacket 7.1 respectively. 7.2 is a surveillance room 10.1 of the first tank jacket shot 3 and, a surveillance room 10.2 of the second tank jacket shot 4 educated.

At the low point TP of the monitoring room 10.1 of the first tank jacket shot 3 is a gathering room 11.1 educated. This consists of an emptying nozzle 12 with removal 18 with the surveillance room 10.1 communicates.

Likewise, the monitoring room is at the low point TP 10.2 a gathering room 11.2 connected, which is led up to about the height of the low point TP of the interstitial space and in an emptying nozzle 13 ends.

The surveillance room 10.1 is through a ventilation line 14 , the outside of the outer jacket 7.2 leads along, the tank jacket near the tank roof 5 penetrates and ends inside the tank above the maximum level. This is necessary to compensate for pressure changes caused by temperature fluctuations in the tank jacket.

The emptying nozzle 12 respectively. 13 are each with a blind flange 15 sealed liquid-tight. The blind flange 15 has a liquid-tight bushing for a leak probe 16 that go into the detection room 17 of the drain port. The leakage probe 16 is connected to a commercially available monitoring device, not shown, which detects the probes 16 detected changes, for example in the continuity of current, resistance or in the capacity, processed, stored and optically and acoustically for display. The leakage probes 16 can also be designed as a sensor cable. It is understood that several collection rooms 11.1 respectively. 11.2 can be distributed on the outer circumference of the outer jacket. It is also part of the device described if a common collecting space is formed along the circumference, which is easily accessible from the outside and is monitored by a liquid probe with an extension.

If the storage medium is changed from an electrically conductive liquid to an electrically non-conductive liquid, for example, the leakage probes are replaced 16 , For this, the leakage probes 16 with their blind flanges 15 from the respective discharge nozzle 12 respectively. 13 solved and replaced by new probes adapted to the storage medium.

If there is a leak, the leakage liquid can flow out of the drain port 12 by means of a withdrawal 18 be drained.

 1

Fixed roof tank

2

tank shell

3

first Tank shell ring

4

second Tank shell ring

5

tank roof

6

tank bottom

7.1

outer sheath Of 3

7.2

outer sheath from 4

8th

distance Cold

9.1

inner sheath Of 3

9.2

inner sheath from 4

10.1

monitoring room Of 3

10.2

monitoring room from 4

11.1

plenum Of 3

11.2

Sammelrum from 4

12 13

drain connection

14

ventilation pipe

15

blind flange

16

leak probe

17

detection space

18

withdrawal

TP

low of the surveillance room 10.1 / 10.2

Claims (10)

Leakage monitoring device vertical vessel walls of at least one-shot standing tanks, containers and silos for storing liquids, in particular liquids hazardous to water, with a monitoring space formed between the inner and outer jacket of the tank or container wall, which has a monitoring device for signal processing, storage and display of a leak in the monitoring room is in operative connection and means for triggering the alarm, characterized in that the monitoring room ( 10.1 ; 10.2 ) at its lowest point (TP) between the inner jacket ( 9.1 ; 9.2 ) and outer jacket ( 7.1 ; 7.2 ) of a tank jacket shot ( 3 ; 4 ) with at least one liquid-tight outer collecting space ( 11.1 ; 11.2 ) to collect leakage liquid and at a position above the maximum product filling height with at least one ventilation line led into the filling space of the tank ( 14 ) is provided, and that in the collection room ( 11.1 ; 11.2 ) a leakage probe ( 16 ) is led to the detection of liquid which is connected to the monitoring device. Device according to claim 1, characterized in that the collecting space ( 11.1 ; 11.2 ) is formed from a plurality of separate receiving spaces distributed on the outside on the circumference of the outer tank wall. Device according to claim 2, characterized in that the separate receiving spaces from emptying nozzle ( 12 ; 13 ) with lockable withdrawals ( 18 ) consist. Device according to claim 1 and 2, characterized in that the collecting space ( 11.1 ; 11.2 ) is formed from a common ring-like receiving space arranged on the outside on the circumference of the outer tank wall. Device according to claim 1 to 4, characterized in that the emptying nozzle ( 12 ; 13 ) several superimposed surveillance rooms ( 10.1 ; 10.2 ) with their withdrawals ( 18 ) approximately at the low point (TP) of the first tank jacket shot ( 3 ) are arranged. Device according to claim 1 to 5, characterized in that as a shut-off means for the removal ( 18 ) a valve with a flange or a screw connection is provided. Device according to claims 1 to 6, characterized in that the leakage probe ( 16 ) in the collecting room ( 11.1 ; 11.2 ) or the receptacles are inserted and exchangeable. Device according to claims 1 to 7, characterized in that instead of the leakage probe ( 16 ) a sensor cable is provided. Device according to claims 3 and 8, characterized in that the leakage probe ( 16 ) or the sensor cable is an electrode arrangement that is responsive to changes in electrical conductivity or changes in capacitance. Apparatus according to claim 1 to 9, characterized in that the tank jacket section ( 3 ) and (4) is connected to one another in a liquid-tight manner by welding, the inner jacket ( 9.1 ) of the first tank jacket shot ( 3 ) compared to the inner jacket ( 9.2 ) of the tank jacket shot ( 3 ) is arranged overlapping against the flow direction of the storage liquid.