CS237558B1 - Device for detecting leakage of electrically conductive liquids along the sealing of expansion joints of tanks - Google Patents

Abstract

The device is intended for detecting leakage of electrically conductive liquids along the expansion joint seals of tanks. The change in electrical conductivity between two electrodes is evaluated, with one electrode in constant contact with the monitored liquid and the other electrode placed along the expansion joint seal. The device can also be used to monitor the tightness of expansion joints of other objects in which electrically conductive liquid substances are stored or flow through them.

Description

The present invention relates to a device for detecting leakage of electrically conductive liquids along the expansion joints of tanks.

So far, the leakage control of electrically conductive liquids along the expansion joints of the reservoirs has only been performed visually on the above-ground parts of the buildings and methods for detecting the leakage of liquids are used with the following disadvantages:

a / The method of measuring wells also signals the presence of ground water that may enter the measuring wells.

b / Method of registering tank level fluctuations. This method is not applicable to tanks in which the amount of liquid in operation is constantly changing.

c / The method of freely placed probes indicating pollutants also registers groundwater contamination by other means, eg when fertilizing the land.

d / The inner vacuum jacket method indicates that this jacket will break even if the wall and bottom joint seals are not broken.

e / Radiometric detection system requires hazardous handling of radioactive substances.

and

The above drawbacks are eliminated according to the invention, which is based on the placement of a metal electrode in a tank, where the electrode is still in contact with the liquid to be monitored and the placement of the metal electrodes along the seals of the expansion joints.

Between the electrode still in contact with the liquid to be monitored and the electrodes disposed along the expansion joints, a change in electrical conductivity is signaled, indicating a leakage of liquid along the expansion joint seal.

The advantage of the device is that by evaluating changes in electrical conductivity between individual electrodes it is possible to determine with certainty which sealing of the expansion joints is damaged. A further advantage is that the change in conductivity between the measuring electrodes is not substantially influenced by any external influences.

An exemplary embodiment of the device according to the invention is shown schematically in the drawing in longitudinal section through two parts of the tank walls separated by an expansion joint.

In the tank 6, the walls and bottom of which are divided by expansion joints 6, there is a liquid to be monitored. Expansion joints 6 are sealed with gasket 6. An electrode 4, for example consisting of a stainless steel wire, is in constant contact with the liquid to be monitored.

Wire electrodes 6, also made of stainless steel, are disposed on both sides of the seal. A safe alternating voltage is applied to the electrodes 6 and 6 by a line 6 from the evaluation device T.

The leakage of the monitored liquid 2 from the tank 5 along the gasket 3 increases the electrical conductivity between the electrodes 6 and 5 and also increases the amount of alternating current flowing between these electrodes 6 and 6, the change of which is actuated by the evaluation device 6.

The evaluation device 6 reports the leakage of the monitored liquid 2 along the seal 6 by light or sound signaling. The electrodes 4 disposed in the expansion joints 8 of the tank 4 along the gasket 4 are connected to the inlet of the evaluation device 4 by separate conductors of the conduit 4.

In operation, all of the electrodes 6 are successively automatically connected to the input of the evaluation device 4 at short intervals of time so that only one of the electrodes 4 is connected to the input of the evaluation device 5 at a time.

The entire cycle of sequentially connecting the electrodes 5 to the input of the evaluation device 7 is repeated continuously, with simultaneous signaling which of the electrodes 5 is connected to the input of the evaluation device 7.

When the monitored liquid leakage 2 is signaled, the automatic switching of the electrodes 6 is blocked by circuits which are part of the internal connection of the evaluation device 6. The evaluation device now signals the leakage of the monitored liquid 2 and at the same time indicates which of the electrodes 6 is connected to the input of the evaluation device 6.

This determines according to which the seal 6 has escaped the monitored liquid 2.

The device operates on alternating current in order to avoid the electrolytic process that would occur when using direct current to potentially damage the surface of the electrodes 4 and 5 and thereby shut down the device.

The invention can be used in particular in agriculture as a control device for detecting leakage of harmful liquids, or in the chemical industry for detecting leakage of electrically conductive liquids.

Claims (1)

SUBJECT OF THE INVENTION Apparatus for detecting leakage of electrically conductive liquids along the expansion joint seals of tanks _from between two electrodes of alternating voltage and one electrode in contact with the monitored liquid, characterized in that the electrodes (5) are located along two sides of the expansion joints (3) The individual electrodes (5) are connected by detachable line conductors (6) to an evaluation device (7) for detecting the leakage point of the electrically conductive liquids (2).