Study Of Application Of Pall Membrane Filter In Primary Brine System Of Ion-exchange Membrane Caustic Soda

With the development of chlor-alkali industry, the technology of ion-exchange membrane electrolysis technology is paid more and more attention in the chlor-alkali industry. This paper combines the preparation of primary brine of ion-exchange membrane caustic soda and the practical of Yangnong Company, study the application of Pall filter in the primary brine of ion-exchange membrane caustic soda.First combined the primary brine process of Yangnong Company, study and discuss the impurities due to the raw materials introduction. By analyzing the data, we put forward the impurity standards needed to control in the primary brine process.Secondly we take refine salt and bittern brine as raw materials in the study of using Pall filter in the system and focus on the process of crude brine. On the condition of making sure the flux and regeneration abilities of filter, we design three experiments schemes to deal with the Ca²⁺,Mg²⁺ and SO₄^2- respectively; compare with the filtration ability of solids when different impurities were added in the refine process; confirm and improve the crude brine process. We study the changing rules of flux by changing the condition of Pall filter, under different pressure between 0.013 to 0.06MPa. Screen of filtration conditions, conclude the best operation pressure is 0.03MPa and the best flux is 1.2 to 1.25m·h^-1. These provide the reference to the design of practical setups.In the end combine the experiments, we also calculate and design the mass balance and the parameters of major apparatus of the primary brine. The Pall filter's operation procedure, methods and relevant control values were confirmed. In the debug of industrial setups, we analyze the unusual conditions which especially on the rupture and tympanic of the Pall filter. By intensity test and SEM, we find the reasons and improve it. In the primary brine process, we solve the problems on the pollution by organic, dissociate chlorine etc, as well as filter element broken and filtration membrane tympanic. We make a first success in the using Pall filter separation technology in primary brine process. Make the traditional process simply, improve the quality of brine significantly and ensure the stable and effective of ion-exchange membrane caustic soda.