Abstract:
A bipolar assembly for filter-press type electrolysers is described comprising a single sheet, whose two faces work respectively as anodic and cathodic wall, characterised by a design of perimetral flanges which greatly simplifies its construction enhancing its reliability. The peripheral flanges are made of a first flange obtained by folding the peripheral portion of the single sheet and of a second flange formed by a rod or a tube with quadrangular section or, alternatively, the first and second flange are pre-formed by folding of adequate strips subsequently fixed to the single sheet. The electrolyser resulting from the assemblage of a multiplicity of assemblies of the invention is particularly suited to the process of electrolysis of hydrochloric acid solutions carried out with chlorine-evolving anodes and oxygen-consuming cathodes.
Abstract:
It is described a bipolar plate consisting of a single wall and a perimetrical sealing frame obtained by folding and provided with a planar abutment surface for the frame-to-wall welding. The wall is further provided with projections on one face thereof preferably obtained by moulding, and with supports on the other face consisting of sheet strips housed in the recesses formed by the concave part of the projections. The projections substantially extend along the entire length of the bipolar plate. The projections and supports are connected to electrodes or current distributors. The projections, the supports, the single wall and the perimetrical frame are made of the same metal or alloy. The electrode or current distributor supported by the projections, the same projections and the supports are welded together by a single pass of arc-welding or preferably laser-welding. The electrode or current distributor connected to the support and the support themselves are mutually welded by a subsequent pass of arc-welding or preferably laser-welding. The welding between wall and perimetrical frame on the abutment surface of the frame is carried out by diode-laser technique, allowing to obtain a robust connection but without a complete melting of the sheet, thereby eliminating the risk of process fluid leakage to the external environment.
Abstract:
The invention describes the design of a discharge duct for bi-phase gas-liquid mixtures in electrochemical reactors, which provides high stability of the outflow in a large variety of process parameters. The system is characterised by a vertical duct (1) wherein the gas and liquid are conveyed at the same time downward and the geometry of the inlet area, which foresees the concurrent presence of two inlet flow sections (3, 4) with different orientations and profiles, is suitable for avoiding both the formation of a discharge pulsating regimen, and the consequent fluctuations of the internal pressure of the electrochemical reactor.