DE102004002217B4 - Device for long-term leak monitoring of double-walled vessel systems, in particular flat tank structures with double tank bottom - Google Patents

Abstract

Facility for long-term leak monitoring double-walled vascular systems, in particular flat tank structures with double tank bottom, comprising a surveillance the tank shell, this being in the lower, near-surface tank jacket area a circumferentially extending Ableitschürze is provided to possible Tank shell leakage fluid to lead to a sensor arrangement and further wherein the diverter skirt merges into a trap for leakage fluid or forms part of such a collection space, as well as an am lowest point of the collecting space provided for controllable shut-off, characterized in that in the region of Doppelwandungs- or Double bottom clearance, penetrating the vessel or tank shell, over the Circumferentially spaced several laps are provided distributed, where at the respective leak from the vessel or Tank jacket connected to a flame arrester and a check valve are and the outlet of the check valve directed to Ableitschürze is, so that leakage fluid from the double wall or raised floor space to the same Sensor arrangement, located on or in the vicinity of the deflector, is guided, which is then capable of both exiting jacket leakage fluid as well as a leakage from the raised floor space to ...

Description

The The invention relates to a device for long-term leak monitoring double-walled vascular systems, in particular flat tank structures with double tank bottom, comprising a surveillance the tank shell, taking this in the lower, near-ground tank jacket area a circumferentially extending Ableitschürze is provided to possible Tank shell leakage fluid to lead to a sensor arrangement and further wherein the diverter skirt merges into a trap for leakage fluid or forms part of such a collecting space, as well as a provided in the lowest point of the catchment area controllable barrier, according to the preamble of claim 1

From the European patent application EP 0 633 460 A2 a device for long-term leak monitoring on double-walled vascular systems, in particular tank bottoms is already known. This arrangement makes it possible, with little effort, to monitor a large number of double-walled tank bottoms cyclically or simultaneously with regard to the occurrence of leaks. By means of the device it can be determined whether a leak has occurred in the outer bottom or in the intermediate bottom, wherein additionally the leakage size and the leak location can be determined. For this purpose, an intermediate layer is applied to the inside of an outer bottom, which serves to support the inner bottom. In the intermediate layer, a sensor cable with variable dielectric constant is laid largely protected. With the special intermediate layer, it is possible on the one hand to divert the forces acting on the tank bottoms and on the other hand to lay the sensor cable at defined locations, which are known in detail. The intermediate layers have special recesses or are laid so that the liquid flow is not hindered. Penetrating into the interstitial space liquid can propagate substantially along an intended direction of slope, towards the sensor cable, so that a timely and rapid detection of leakage is possible. The liner after EP 0 633 460 A2 is arranged so that in a first embodiment, a meandering laying of the sensor cable is possible. In a second embodiment, the sensor cable is laid helically on the inside of the outer bottom. It is also possible to lay the sensor cable on concentric circles on the inside of the outer bottom with different radii, with several Sensorkabelein- and sensor cable versions are provided for connecting and connecting the sensor cable to an evaluation device outside the tank.

It However, it has been shown that due to the necessary intermediate layer, for example, made of angle steel, yet a hindrance a leakage flow is given, especially if only small amounts of leakage occur. This in turn delays contacting the leakage with the sensor cable.

Farther is the introduction or subsequent thread of the sensor cable into the interstitial space technologically difficult and time consuming and costly. An optical Visual inspection of the laid cable is not possible. In case of damage of the cable it is as well problematic, the damaged one To remove cables.

In the device for long-term tank jacket leak monitoring after DE 196 00 970 C1 should be possible in particular for tank farms a review of the tightness of the tank shell by a sensor cable arranged on the outside. For this purpose, a height moderately at least partially disposed below the bottom of the flat tank structure and this outer peripheral surrounding annular collecting space via a slope having a collar connected to the lower end of the outer shell of the tank. The sensor cable is in this case on the cantilever or is located in the bottom area of the collecting space, eg in the channel bottom.

In the case where leaked due to leakage liquid from the tank farm, this runs either along the tank shell and enters the side of the collecting space, which is formed from cantilever and gutter. By a corresponding contact with the sensor cable then a leak alarm can be triggered. As a result, on the one hand leak alarm can be triggered early and on the other hand enough time remains to eliminate the accident, without any environmental hazard. The cantilever and the annular tube form the above-mentioned collecting space, which is able to collect even in the event of major leaks, emptying the tank and / or removing the leak, environmentally hazardous liquids. The cantilever and the catchment area are sufficiently far away from the tank shell, which means that in the case of a larger leak, even larger quantities of liquids that leak sideways can be caught and come in contact with the sensor cable. The sensor cable is also arranged in this case in the region of the cantilever or in the bottom area of the collecting space, for example in the bottom of the channel. The fact that the sensor cable is designed to be fluid-selective, for example, penetrating rainwater does not lead to the erroneous triggering of a leak alarm. The cantilever and the annular tube, both of which form the collecting space, can later in the lower Bodenab cut, the tank jacket surrounding, be attached, so that can be achieved without complex construction measures, a higher level of protection against environmental risks. The sensor cable after DE 196 00 970 C1 communicates with an evaluation device, which detects the emergence and the formation of a leakage flow contact and triggers the desired alarm in this case. At this time at the latest, a barrier, which is provided at the collecting space and which otherwise serves to drain precipitation, is closed.

In implementing the solution after DE 196 00 970 C1 It has been found that with a structurally justifiable effort a collecting space of sufficient size can be formed per monitored flat tank construction. The position of the sensor cable on the cantilever is optically controllable and it can be made targeted manipulations to check the functioning of the leakage system by applying a test amount of kohler hydrogen-containing liquid on a cable section, which then leads to alarm triggering.

A Complete leakage detection for both the intermediate floor double-walled Flat tank construction as well as the review of Tightness of the tank shell leads under consideration of the above-described solutions of the prior art inevitably a complex sensor cabling with correspondingly higher evaluation requirements.

From the U.S. Patent 4,939,833 shut-off valves for containers are previously known, which moreover have means for leak detection.

Regarding the state of the art to flame arresters for piping is still on the DE 43 38 013 C1 directed.

Out In the foregoing, it is therefore an object of the invention to develop a further Device for long-term leak monitoring double-walled vascular systems, Specify, in particular, flat tank structures with double tank bottom, which on the one hand a monitoring the tank shell allows and on the other hand, monitoring the tightness of the tank bottom assembly allows, without discrete sensor arrangements or sensor systems for the intermediate floor monitoring and the control of the tank shell will be required. The to be specified Device should allow multiple fault location and on the other hand the licensing requirements for explosion-proof Applications are sufficient.

Farther It is an object of the invention that the device for long-term leak monitoring in existing flat-bottom tanks of any size as well at reception areas, which no longer meet today's requirements, in a simple manner and with manageable Costs can be retrofitted should.

The solution The object of the invention is achieved with a device for long-term leak monitoring double-walled vascular systems, in particular flat tank structures with double tank bottom according to the combination of features according to claim 1, wherein the dependent claims expedient refinements and developments represent.

Therefore the basic idea of the invention is a proven tank jacket monitoring system to combine with a double floor construction for flat tank structures, the tightness of the container bottom monitored by the sensor arrangement of the tank jacket monitoring system at the same time becomes.

According to the invention, this is in the range of the double wall or double floor space, the vessel or Pervading tank coat, over Spaced apart the circumference, the design distributes a plurality of leaks provided, with the respective leak from the vessel or Tank jacket connected to a flame arrester and a check valve are.

Of the Outlet of the check valve is the existing diverter of the Tank shell monitoring system directed, allowing leakage fluid out the double wall or raised floor space to the same sensor arrangement, arranged on or near the deflector apron, guided which is capable then not only exiting jacket leakage liquid to detect but also that leakage fluid coming out of the double bottom space in the event of leakage of the internal soil.

According to the invention is on the deflector apron a plurality of spaced, strip-shaped sheets or angles arranged, which on the one hand a Anstaufläche for leakage fluid form and on the other hand provide protection for those in the respective Anstaubereich create a sensor array.

Of the Outlet or the outlet of the respective check valve is in front of a each of the Anstlälächen lying.

Prefers is the outlet or the outlet of the respective shut-off valve for Middle of the respective strip-shaped Sheet or angle oriented.

The Number of leaks with a tank diameter of up to 20 m is four. With a tank diameter between 20 m and 50 m are six Leak sockets and provided with a tank diameter over 50 m eight leaks, wherein the nozzle preferably arranged on the tank circumferentially equally distributed is.

at an advantageous embodiment of the invention are vascular or Tankinnenseitig between the inner tank bottom and the Tankinnenwandung cohesively and arranged tightly encircling ring angle, with the leak in Lead the space enclosed by the ring angle. The connection between if necessary subsequently introduced tank bottom and the tank inner wall takes place exclusively on the aforementioned Ring angle.

The Flame barrier as a prerequisite of approval for the application of the device according to the invention in potentially explosive atmospheres Areas is for example a so-called detonation tube fuse. The check valve may be preferred as a ball valve or shut-off ball valve accomplished be.

The Ableitschürze the tank monitoring device leads to a manifold having a plurality of inlet slots, wherein the controllable barrier connected to the bottom of the manifold is.

Prefers in the so-called 12 o'clock position can be upstand at the manifold to increase of the retention volume be arranged in the collecting space.

Of the inner, retrofitted or retrofittable Tank bottom consists e.g. from a welded tear sheet arrangement.

Also For example, the inner tank bottom may be a smooth-sheet arrangement, wherein Spacer to the outer tank bottom a steel mat or a steel mat mesh, in particular Baustahlgeflecht is provided.

When Sensor assembly may include a hydrocarbon-sensitive cable associated evaluation and protocol device find use.

The Hydrocarbon-sensitive cable is then preferred as a strand on the deflector apron laid.

Out the known, determined by cable assembly coordinate assignment the respective shut-off valve to the respective cable section is in Leakage case the leak location determinable.

Ausgestaltend each leak can with check valve an inner floor quadrant be assigned and it can the respective quadrants have a slope so that leaks in the respective quadrant preferred to the associated leak nozzle reach.

These measure Improves quick leak detection even in case of failure Repairs to large capacity and large capacity tank farms.

The Shut-off valves, which are arranged on the respective leakage nozzle, can be closed by hand in case of leakage of the double floor. Also in the embodiment of the invention is the possibility these check valves, after a leak has been detected, electronically or close by electric motor.

The outer peripheral side Laying the sensor arrangement, in particular in the form of a sensor cable, on the deflector apron allows the optical control, e.g. on possible damage, and a light exchange, if necessary.

The Sensor cable is routed so that leaks caused by a leak the tank wall over the deflector apron reach the sensor cable, alarm at the connected monitoring unit trigger.

at Leaks of the upper or inner soil in the tank accumulate Leaks in the space between lower and upper, i. between outer and inner ground and get over the leaks to the outside on the deflector apron. There, the leakage is detected by the tank jacket monitoring system and also an alarm triggered. The selection of the leakage detection systems corresponds to the respective ones Requirements for selectivity.

Next the leakage detection and location system known from the prior art under the influence of fluid variable Dielectric is also possible to use a fiber optic sensor cable, which Raman backscatter effects exploiting, when contacting with a medium other temperature related to the ambient temperature is capable of spatially resolved alarm signals to provide.

The sensor arrangement or the sensor cable arranged on the deflector apron is overflowed in the event of rainwater. The rainwater can then flow through the collecting pipe into the existing rainwater discharge. The rainwater discharge and the shut-off valve provided there are only then closed when a leak has been detected.

The Invention will be described below with reference to an embodiment and below With the help of figures closer explained become.

in this connection demonstrate:

1 a schematic diagram of the overall arrangement;

2 a plan view of a flat tank construction with deflector and manifold;

3 a detailed representation along the line AA according to 2 ;

4 a cross-sectional view of the manifold and a part of the deflector and a detailed view X with respect to the embodiment of the opening slots in the manifold and

5 Variants A to D of embodiments of a retrofitted double floor.

According to the schematic diagram according to 1 a flat tank construction has a tank jacket 1 and a raised floor 2 on.

At the tank bottom 1 is a deflector apron 3 eg connected by welding. The width of the deflector skirt is designed as a function of the desired retention volume and is, for example, in the range between 500 mm and 1000 mm.

The deflector apron 3 goes into a collecting pipe 4 over which slit-shaped openings 5 having.

These openings have dimensions of about 20 × 200 mm and are all 2000 mm pipe length intended.

On the deflector apron 3 is a strip-shaped sheet or a L-steel angle 6 attached, which forms a chaffing surface for possibly leaking leakage and at the same time provided as the sensor assembly sensor cable 7 protects.

Outer peripheral side of the tank shell 1 are several leaks 8th provided that connect to the raised floor 2 produce (see also 3 ).

The sensor cable 7 leads to a monitoring device 9 that in turn with a PC control room 10 in addition to the data printer for logging the monitoring results. At the monitor 9 is a potential-free contact for switching a controllable shut-off 11 provided, which is able to drain the rainwater 12 to close when detecting a leak.

To increase the collecting volume may preferably at the so-called 12 o'clock position of the manifold 4 an upstand 13 , again in particular by welding, are attached.

Of the Diameter of the manifold has a nominal diameter of DN 100 to DN 200 or bigger on and is also dependent of the desired retention volume designed.

The plan view of a flat tank according to the embodiment of the invention according to 2 leaves a total of four leaks 8th recognize, which are provided uniformly spaced over the circumference of the tank. Likewise are in the 2 the strip-shaped L-steel angles 6 recognizable, which serve the leading receptacle of the sensor cable and which form the mentioned Anstaupläche.

The structure of the leak port connection on the tank shell is using the 3 clear.

Inside the tank is between the inside of the tank shell 1 and an example subsequently introduced inner, new tank bottom a ring angle 15 connected by welding. In the connection area of the nozzle, the existing tank wall has a reinforcing plate 16 on.

At the tubular nozzle is a detonation fuse as flame arrester 17 connected, which outlet side with a check valve 18 communicates.

The spout 19 of the shut-off valve designed as shut-off ball valve 18 lies in front of the sensor cable 7 in the area of the L steel angle 6 , The deflector apron 3 has a gradient for liquid transport, which can range from 1.5% to 15%.

Based on the cross-sectional view of the manifold and a part of the deflector apron 4 is also the execution of the upstand 13 and the location of the slot-shaped openings 5 in the manifold 4 recognizable.

Variants A to D of possible embodiments of a retrofitted double floor are in the 5 shown.

at variant A becomes tear sheets butt-welded on the existing tank bottom, being used as a weld pool a backing strip with tear is provided.

According to variant B, the tear sheets are overlapped welded. Variant C is based on a smooth-plate arrangement, which is butt-welded. There is also a weld pool protection there provided in the form of a Unterlegstreifens.

Either in the smooth-plate variant to C and D is used as a spacer the existing tank bottom a mild steel mat in particularly cost-effective and easy to use.

In summary allows the tank monitoring device according to the embodiment with a single, easy-to-install sensor array, the preferred consists of a sensor cable, monitoring both the raised floor space as well as a tanker coat. Through this possibility of quasi-external Sensor arrangement, it is no longer necessary to larger distances in the raised floor area create a cable receptacle and cable management to detect a leak guarantee. The arrangement and training of several, tank outer peripheral side Distributed leaks ensure that even small leakage quantities relatively fast over the respective check valve and its outlet or outlet to the sensor arrangement reach. Even with a conceivable large-scale destruction of Tank interior bottom is the maximum leakage flow rate through the arrangement delimited from the drain and check valve, allowing enough time remains to close after detection of the leakage, the valves and suitable disaster control measures to initiate and carry out. Here is in particular the structurally created large catchment area advantageous.

1

tank shell

2

Raised floor

3

Ableitschürze

4

manifold

5

slotted opening in the manifold

6

L-angle bar

7

sensor cable

8th

leak socket

9

monitor

10

PC control room

11

controllable Shutting off the rainwater discharge

12

Precipitation sewer

13

backsplash

14

new inner tank bottom

15

ring angle

16

Support panel

17

flame arrester / Detonation tube fuse

18

check valve

19

outlet or outlet of the check valve

Claims (14)

Device for long-term leak monitoring of double-walled vascular systems, in particular flat tank structures with double tank bottom, comprising a monitoring of the tank shell, for this purpose in the lower, near-surface tank shell area a circumferentially extending Ableitschürze is provided to lead possible tank jacket leakage liquid to a sensor array, and further wherein the Ableitschürze passes into a collecting space for leakage fluid or forms part of such a collecting space, as well as provided at the lowest point of the collecting space controllable barrier, characterized in that in the region of the double or double bottom space, the vessel or tank shell penetrating, over the circumference distributed spaced a plurality of leaflets are provided, wherein the respective leak nozzle starting from the vessel or tank shell, a flame arrestor and a check valve are connected and the outlet of the check valve for Ableits apron is directed so that leakage liquid from the double wall or double bottom space to the same sensor array, located on or in the vicinity of the deflector, is guided, which is then able both exiting jacket leakage liquid and a leakage from the raised floor Detachment space and on the deflector apron a plurality of spaced-apart strip-shaped sheets or angles is arranged, which form a Anstaugläche for leakage fluid and in the respective Anstaubereich the sensor assembly is located. Device according to claim 1, characterized that the outlet or outlet of the respective check valve before a respective abutment area lies. Device according to claim 1, characterized that the outlet or the outlet of the respective check valve is preferred to the center of the respective strip-shaped sheet or the angle is oriented. Device according to one of the preceding claims, characterized characterized in that the number of leaks at a tank diameter of up to 20 m four, about 20 m to 50 m diameter six and over 50 m diameter is eight, with the nozzles are mounted evenly distributed on the tank. Device according to one of the preceding claims, characterized in that vessel or tank inside between the inner tank bottom and the tank inner wall materially and tightly a circumferential ring angle is arranged, wherein the leak-tight in the ring angle umschlos lead into this room. Device according to one of the preceding claims, characterized characterized in that the flame arrestor as a detonation fuse and the check valve are designed as a ball valve. Device according to one of the preceding claims, characterized characterized in that the diverter skirt leads to a manifold, which several Having inlet slots, the controllable barrier at the bottom connected to the manifold. Device according to claim 7, characterized that in the 12 o'clock position at the manifold a Aufkantung to increase the Retention volume the collecting space is arranged. Device according to one of the preceding claims, characterized characterized in that the inner tank bottom of a welded teardrop arrangement consists. Device according to one of claims 1 to 8, characterized that the inner tank bottom is a smooth-sheet arrangement, wherein Spacer to the outer tank bottom a steel mat or a steel mat mesh, in particular Baustahlgeflecht is provided. Device according to one of the preceding claims, characterized in that the sensor arrangement is a hydrocarbon-sensitive cable with evaluation and Protocol device includes. Device according to claim 11, characterized in that that the hydrocarbon-sensitive cable laid as a strand on the diverter skirt is. Device according to claim 2 and 12, characterized that from the known, determined by cable assembly coordinate assignment of respective check valve to the respective cable section in case of leakage the leak location can be determined. Device according to claim 13, characterized in that that each leak with check valve a Innenbodenquadranten is assigned and the respective quadrants have a gradient, so that leaks in the respective quadrant preferred to the assigned Get the leak.