How much negative pressure in the cathode chamber affects the electrolyzer?
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This post was last edited by fws5850 on 2020-12-18 at 10:06. In the shutdown state of the natural circulation electrolyzer using Beihua Machinery membrane electrodes, after cleaning the inlet filters for the anode and cathode, they were reinstalled to check for leaks. Pure water was filled into the main inlet pipes for the anode and cathode, and then the liquid was drained; no pressure was present after draining from the anode, while draining from the cathode too quickly resulted in a negative pressure of -12 KPa (there was only a small amount of nitrogen at the end of the tank, so the liquid-level gauge was replaced with a level indicator). I would like to ask the experts: what impact will this have on the electrolyzer?
This is caused by insufficient N2 supply at the tail of the tank during drainage; it may lead to a decrease in the elasticity of the cathode mesh, an increase in the distance between the cathode and anode, and if there are broken wires in the mesh, they can puncture the membrane, causing holes in it. To determine the exact situation, it is necessary to apply full current after starting up the system and compare the voltage levels with those before shutdown.
Yes! The main reasons were the failure to increase the nitrogen at the tail of the cell in a timely manner, as well as a lack of understanding regarding the replacement of the liquid-phase differential pressure gauge with a level gauge in the electrolyzer.
12 kPa should not have much impact on the electrolyzer. If the total voltage is slightly lower than before stopping, there’s no problem with the full-charge current.
Thank you all for your advice! I hope there won’t be any major problems; otherwise the losses will be quite significant, over a million.:'(
Today, a membrane leak test was conducted, and no bubbles were detected in any of the 172 cells in the electrolyzer! One really has to be careful and meticulous when working with electrolyzers!
The theoretical pressure limit of the elastic mesh is 2 meters of water column pressure; exceeding this pressure can cause damage, which represents a fairly high level of risk. Over time, the mesh will also deform, as some netizens have mentioned, with an increase in the spacing between the mesh elements.