Electric current sensing and management system for electrolytic plants

Abstract

The present invention relates to an electric current management (ECM) system and method comprising at least one electrolytic cell having at least two electrodes in contact with electrolyte media; a plurality of sensor means for measuring the current passing through one or more electrodes, said sensor means being located inside at least one ECM bar installed in one or more operating electrolytic cells; a support means for supporting at least one ECM bar in each cell; wherein the support means is adapted to avoid disruption to normal electrode movements and damage to the ECM bar. The present invention introduces improvements for minimizing the effects that several types of variables have on current measurement, such as magnetic field interference, cell geometry and contact configuration, in order to provide a reliable approximation of the current passing through each electrode. The present invention can be applied to real time monitoring of each cathode, or anode, constituting a metal electrowinning or electrorefining cell or other electrolytic cell.

Description

FIELD OF APPLICATION[0001]The present invention relates to metallurgical systems, especially electrometallurgical systems, and enhancement of electrolytic cell and / or tankhouse behaviour.[0002]The present invention can be particularly applied to real time monitoring of each cathode, or anode, constituting a metal electrowinning or electrorefining cell or other electrolytic cell with parallel electrodes.BACKGROUND[0003]Metal extraction processes, such as those for copper, often include electrowinning or electrorefining recovery steps. With regard to these steps, it provides an advantage to monitor in real time each metal plate's performance in order to achieve optimum performance of the electrolytic plants.[0004]Within the electrolysis process, a short circuit may occur if electrodes are arranged misaligned; when due to physical flaws metal growth is not uniform on a surface, which may be a result of operational issues such as impurities, higher than acceptable cathode currents, part...

AI Technical Summary

Benefits of technology

The present invention relates to improvements in metallurgical systems, particularly electrometallurgical systems, for enhancing the behavior of electrolytic cells and tankhouses. The key factor is the improvement of electric current management, including its measurement and control. The invention introduces an electric current management system comprising electrodes, sensor means, and a support means for supporting the electrodes in each cell. The support means is adapted to avoid disruption to normal electrode movements and damage to the support bar. The invention also addresses the various factors that can interfere with current measurement, such as magnetic field interference, cell geometry, and contact configuration, to provide a reliable approximation of the current passing through each electrode. The improvements can enhance metallurgical systems by maximizing the device's functionality, adaptability, and control, providing a full enhancement of systems where the management of electric current is essential. The patent text is particularly applicable to real-time monitoring of each cathode or anode in electrowinning or electrorefining cells with parallel electrodes.

Problems solved by technology

Within the electrolysis process, a short circuit may occur if electrodes are arranged misaligned; when due to physical flaws metal growth is not uniform on a surface, which may be a result of operational issues such as impurities, higher than acceptable cathode currents, particulates in the electrolyte, damaged electrodes or peeling of electrodeposits that then touch the neighbouring electrode, among others.

A low current situation may also occur when there is a poor electrical contact between anodes or cathodes and their current source, resulting in a reduction of the system efficiency.

Both cases can lead to a low quality product, or as in the case of copper electrorefining, the desired purity is not achieved, wherein these cases can also lead to a reduction in current and power efficiency which can reduce plant production and increase costs.

In particular, the presence of the current sensing systems of the prior art can cause difficulties with electrode removal / replacement in a cell, due to the propensity of the electrodes to knock the sensor system as they are being lowered into the cell, causing damage to sensor systems and interfering with efficient loading of electrodes into the cell.

The crane bale and strong back electrode hooks used to pick up cathodes and anodes may in themselves provide means for damage to the sensor system.

Such a system does not yield a reliable measurement of the electric current passing through an electrode, as “ideal” theoretical scenarios rarely occur in practice.

Thus, the prior art method based on theoretical calculation does not cater for additional magnetic field contributions.

Additionally, the solution proposed in the prior art does not consider the external effects of the measurement, such as temperature, which affects both the behaviour of magnetic fields and the electric current measured.

In addition, conditions within electrowinning and electrorefining cells are very harsh.

As serious as this is, the physical environment with the frequent process of removing and replacing electrodes give many opportunities for damage to the sensors and for impeding of the movement of the electrodes by the sensors.

The versions described in the prior art are not robust to said conditions which would result in frequent failure.

As an additional constraint, in many cell systems a bar with round profile will not fit beneath the electrode header bars due to the thickness of its profile impeding the path of electrodes as they are lowered into the cell and electrode lifting hooks as they may be lowered beneath the header bars to lift the electrodes by their header bars.

Then, there is no clearly defined prior art for sealing a non-round section of non-round profile tubes in a manner that is suitable for this application.

The known standardised methods available in the art such as flanges and threaded end caps, are geometrically prohibitive for a non-round profile.

Internal methods of sealing such as o-rings are not practical due to the tight radius bends that may be present in the corner or corners of non-round profile tubes.

Gluing, epoxy resin and bonding a plug in the end of the tube were attempted by the Applicant but failed, due to what was understood to be differences in thermal expansion between the bonding material and the tube housing.

In addition, in the event of human error such that data is not recorded correctly and cells are not harvested within an acceptable band of time periods, inconsistent cathode weights, poor morphology, short circuits, damaged anodes and reduced current efficiency can result.

Where plants have fully automatic cranes these cranes can record the exact time that cells are harvested but such systems are expensive and most tankhouses do not have these cranes.

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