The impact of frequent start-up and shutdowns in chlor-alkali production
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This post was last edited by sunjl1981 on 2013-1-6 23:29. In chlor-alkali production, frequent start-up and shutdowns of the electrolysis plant have a significant impact on the electrode coatings, membranes, and various control parameters. But exactly how does this impact occur? I hope my friends can provide a specific and detailed analysis. Thank you! # ， ， &
Frequent starting and stopping have a significant impact on the electrode coating; after shutdown, the anode becomes the cathode due to the back electromotive force, which causes the anode coating to dissolve and leads to an increase in the anode potential. The membrane contracts and expands repeatedly, resulting in a shift in the neutral zone (the membrane channel), as well as a decline in the membrane’s mechanical strength and selective properties, thereby exacerbating the side reactions in the electrolyzer. The overall result is an increase in slot voltage, a decrease in current efficiency, and an increase in power consumption; frequent start-up and shutdown operations should be avoided as much as possible.
In chlor-alkali production, frequent start-ups and shutdowns are to be avoided at all costs, as they severely affect production, lead to cost losses, reduce the service life of the membranes, cause voltage increases, lower efficiency, raise power consumption, intensify side reactions, and decrease the purity of chlorine. They can also allow large amounts of impurities such as calcium carbonate to enter the electrolyzer through the pipes
Thank you all! When removing the grooves, a brownish-red layer often forms on the diaphragm and the anode. Experts, could this be iron? If so, why is the iron content measured in the brine fed into the tank not high?
Frequent starting and stopping can also lead to the peeling off of the coating, especially on metal anodes, whose coatings are usually applied by spraying or brushing.
1. It has a greater impact on ordinary membranes, disrupting their equilibrium state and affecting the operational efficiency and performance metrics of the electrochemical cells； 2. Moreover, frequent start-up and shutdown operations can have a certain impact on safe and environmentally friendly production ； 3. It has a greater impact on newly created grooves shortly after their creation, potentially causing damage to the membrane as well as an increase in hydrogen content in chlorine ； 4. Therefore, one week or ten days before planning to stop production, no more tank cleaning plans are arranged, for the same reason.