The electrolyzer keeps having problems; I don’t know how to maintain it (Please, fellow Sichuanese, share your insights.)
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This post was last edited by sunjl1981 on 2013-1-6 at 23:42. I just graduated a year ago and am working at a chlor-alkali company. Our factory has 6 electrolyzers for chlorine production; it is estimated that one of them breaks down each month. Whenever a problem occurs, everyone worries about it, and in the end the solution is to disassemble the electrolyzer and replace its membrane. A few days ago, several saltwater feed pipes became clogged. How should this situation be handled? Recently, there has been a leakage of alkali droplets on the cathode side of cell XX# in the electrolyzer; I’m not sure what caused it What aspects should be considered when maintaining electrolyzers? (Note: Our factory uses brine to produce soda ash, and the concentration of sulfate ions is above 8 g/l. We hope that our colleagues from Sichuan will kindly offer their advice.) This post was last edited by limingshuguang on 2008-1-15 09:24 ] # ， ， &
The blockage of the brine feed pipe may be related to the sedimentation aid TXY; it reacts with chlorine on the anode side to form viscous substances, thereby causing blockages in the brine feed pipe. It is necessary to regularly clean the anode solution circulation tank, as well as the filters at the inlet of the tank and at the pump outlet. As for the cathode side, the leakage of alkali droplets may be caused by the aging of rubber gaskets or corrosion of the electrode plates. This post was last edited by limingshuguang on 2008-1-15 at 10:55
One unit breaks down each month. How long has the ion exchange membrane been in use? What is the pressure and differential pressure control for hydrogen chloride, and what is the level of heavy metal ions in the catholyte? In ion-exchange membrane electrolysis, it is necessary to maintain stable hydrogen chloride pressure and pressure differences. If the pressure difference is unstable, friction between the membrane and the electrode surfaces can occur, leading to the formation of pinholes that pose a risk to safe production; in such cases, the cell must be disassembled and the membrane replaced. Regarding alkali leakage on the cathode side, it may be due to aged gaskets or nuts that have loosened as a result of temperature differences. If it is caused by aged gaskets, the system should be shut down for replacement; if the nuts are loose, simply tightening them again will suffice.
I have been driving for 1 year and 3 months now. The pressure difference between chlorine and hydrogen is kept around 350 mm; the chlorine pressure is approximately between -10 and -40, while the hydrogen pressure is around 300 to 330. These are my observations regarding the pressure difference – they’re not official figures. Nevertheless, there are still changes in pressure, and the current levels change frequently. The pinhole issue you mentioned was detected a few days ago; nearly ten new films have been installed. I didn’t know that alkalis contain heavy metals. . .
Frequent changes in current will cause the membrane to expand and contract repeatedly, leading to wrinkles and delamination. If the pressure difference is not properly controlled during these current changes, the membrane may swing and rub against the electrodes, resulting in pinholes; therefore, it is important to maintain a stable current level.
Are there several saline feed pipes blocked? Has it been determined what is causing the blockage – mechanical debris or something else? Or is it simply the case that there is no brine in the feed pipe? The leakage of alkali at the cathode is most likely due to a problem with the gasket. Since you haven’t been driving for long, other possibilities are unlikely. A high sulfate content in saline generally only affects current efficiency and membrane performance. If the membrane is changed frequently, the quality of the saline should be considered. The removed membrane should be checked for pinholes or tears. Where do pinholes mainly appear? Based on the phenomena you described, I personally believe the issue may lie in the installation process – uneven forces applied during installation and excessive torque can lead to poor sealing of the gaskets as well as damage to the diaphragm. However, the specific situation needs to be analyzed based on the actual conditions on site. There is much to learn in chemical production; attention to detail reveals knowledge everywhere.
Yes, you make a good point; I only now realize the importance of controlling the pressure difference. I would like to ask you: does a change in current from 14.6 KA to 14.7 KA constitute an increase in current? Our company often does this; the current level rises or falls by 1-2 KA every few days.
The reason you mentioned is indeed valid; our company’s maintenance workers are indeed careless when installing ion membranes, and their technical skills are not very good. There is a lack of supervision and guidance from skilled technicians, and mistakes are only fixed afterwards. Knowledge is absolutely essential! ! !