Electrical supply device for cathodes in soda-chlorine diaphragm electrolysis cell using plug welds through copper plate to ensure electrical connection to tank side wall

摘要

Ensuring electrical connection between a copper plate and the side wall of the tank is by an array of plug welds via an array of openings made in the copper plate, so the ends in electrical contact with the side wall are arranged in a manner such the routes taken by the current from each plug weld to the end of the nearest grid bar are all identical. Electrical supply device for cathodes (12-1 to 12-n) in a soda-chlorine diaphragm electrolysis cell comprising an electrolysis tank (10) and a number of cathodes and anodes of equal number, alternated and parallel to each other. The device contains an electrical connection element (16) formed of at least one copper plate fixed by electrically connecting means on the outside wall to one of the side walls of the electrolysis tank (11) and electrically connected on the inside wall to the cathodes by grid bars (14-1 to 14-n). The number of plug welds (18-1 to 18-m) is equal to the number of cathodes and the end of each plug welds is opposite the end of the grid bar associated with the corresponding cathode. Alternatively, there are half as many plug welds as there are grid bars, with each plug weld placed half-way between the ends of two grid bars. The copper plate is made of a number of superimposed thin copper plates of the same width but different lengths. The largest plate is fixed to the side wall of the tank and the plates are placed so the section decreases between the first and last cathodes to be supplied so each cathode is supplied with approximately the same current intensity. The plug welds are made of a conductive material with low resistivity, such as copper or copper aluminium alloy. The largest copper plate is fixed to the tank side wall by a peripheral weld and the plates are also fixed to each other by peripheral welds.