Zero Gap Electrolysis Process Research

The key equipment in chlor-alkli industry is electrolyzer. With the development of chlor-alkli industry, the process and new technology in caustic soda production has experienced three stages, from mercury method, diaphragm method to ion exchange membrane. The method of ion exchange membrane is the most advanced way to produce caustic soda. The key equipment electrolyzer also have been developed from mercury electrolyzer, diaphragm electrolyzer to membrane electrolyzer with the progress in power consumption, product quality and investment saving, or more stable and better environmental protection chemical process. In this work, we mainly study the most advanced chlor-alkli process and control technology by using zero gap electrolyzer to produce caustic soda.In this work, we firstly introduced the history of chlor-alkli process, the inner structure of zero gap electrolyzer; and mainly explained the electrolysis process by using zero gap electrolyzer.Because the cathode side of zero gap electrolyzer is much improved,from the structure with the space gap to mattress, the zero gap electrolyzers need a more stable operating condition. Therefore, the electrolysis process also is modified, including the design of purified brine tank, decreasing operation pressure, the design of the alarm and interlock of pressure and pressure difference of each single electrolyzer. And the control system design of the electrolysis process of zero gap electrolyzer is also discussed in this work.