Diaphragm valves for chloroalkali electrolysis plant in Taiwan
At the end of the year, Luxemburg-headquartered SISTO Armaturen S.A., a member of the KSB Group, will supply 1550 diaphragm valves to Taiwan.
Example of the SISTO-16S/20 valves to be used for the Taiwanese chloroalkali electrolysis plant. (Image: KSB)
The valves are needed for upgrading a plant built by Japanese companies seven years ago and situated 250 kilometres to the south west of Taipei. The valves have nominal diameters of between 20 and 150 millimetres. All valves included in the scope of supply feature a diaphragm made of EPDM which is protected on the fluid side by a TFM plastomer film. An additional PVDF barrier film placed between the EPDM and the TFM prevents gas diffusion and thus protects the valve internals from aggressive chlorine gas. A metal spiral which supports the diaphragm from behind provides the SISTO-16S valves with long-term operating reliability, even at a temperature of nearly 90 °C. Taking into account the site s location near the coast and the salinity of the ambient air caused by the process, all valves will be supplied with a 240 µm thick top coat of special paint. Around the world, the so-called membrane electrolysis process has almost entirely replaced the various processes used in the past for the industrial production of chlorine, caustic soda and caustic potash. It is particularly environmentally friendly, because there is no risk of asbestos or mercury contamination. The final products are considered clean. The Luxemburg-based manufacturer was awarded the contract because the Taiwanese final customer had already used the enclosed TFM/PVDF/EPDM diaphragm with support spiral for earlier projects and was impressed with the product’s performance. Delivery will be complete by the end of 2011.
Source: KSB SE & Co. KGaA
