Steady Atate Simulation And Analysis Of Caustic Soda Electrolysis Process

Caustic soda electrolysis technology, a very important country alkali technology with a characteristic of high NaOH concentration and small pollution, have been recognized as the world's most technologically advanced and most cost-effective alkali electrolysis technology. Therefore, in-depth analysis of its internal mechanism and characteristics is of great significance to its design and operation.Firstly, based on an actual device operating conditions as well as the physical parameters, the brine purification, membrane electrolysis, and hydrogen chloride absorption steps are modeled, respectively, using AspenPlus V8.4. Excel cell unit is developed and used for the steady-state simulation. The results obtained show good agreement with the field data and this verifies the accuracy and effectiveness of the resulted model.Secondly, the two section design membrane electrolysis process sensitivity analysis. For the brine purification section to study the effect of concentration of feed lye and sodium carbonate solution on the refining unit performance; for HCL unit, the influence of the amount of absorbent, temperature and pressure on the system performance. The simulation results in refined brine NaCL purity of 310kg/m3 or more, the finished cathode lye NaOH mass fraction of 32.6%, HCL absorber bottom liquid mass fraction of 31.0%,, the results are in reasonable range. The paper reveals the caustic soda electrolysis process in some of the key point in the process, for the design and operation of the system provides a valid pointer.