In cases where there is a membrane leak, what are some good methods to determine the extent of the leak?
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This post was last edited by sunjl1981 on 2013-1-6 20:16 after opening the polarized cell. The voltage of several slots is either high or low. It is said that there is a leak in the membrane. What are some good ways to determine whether there is a membrane leak, in case the membrane is no longer functional? Should it be replaced or repaired? 100 unit slots are designated for this repolarization slot. Can we use a few less? Does it affect driving? This post was last edited by yzhms on 2009-2-26 12:34. ] # ， ， &
What model of electrolyzer does the poster have? Is it from Chlorine Engineering, Beihua Machinery, Asahi Kasei, Woody, or some other company?
A low or high cell slot voltage is not necessarily due to a problem with the membrane; the electrocatalytic performance of the electrodes, the flow rate of the electrolyte, the concentration of the electrolyte, and the temperature of the electrolyte all have an impact. It’s just that the internal monitoring of each cell slot cannot fully reflect the situation, preventing us from making further judgments; it’s not possible for every cell slot to have a monitoring system as comprehensive as that of an electrolyzer! It is possible to determine this by performing a membrane leak test while the vehicle is parked; of course, it is also possible for problems to arise while the vehicle is in use! For membrane leaks, it is possible to carry out repairs using ion membranes, but this approach is not useful for large-scale leaks! The removal of the polarization slot units is possible, but it is best to remove two unit slots at the same time from both the positive and negative halves! It can be done based on the stroke of the hydraulic press, but it is essential to ensure the pressure exerted by the hydraulic press on the electrolyzer! Once, we removed too many unit slots; the pressure on the hydraulic press was normal, but after starting the machine, gaskets started to leak. Upon inspection, it was found that the stroke of the hydraulic press was insufficient. Although the pressure shown on the control panel appeared to be sufficient, the pressure acting on the unit slots was not enough. This is because once the stroke of the hydraulic press reaches its limit, the pressure inside the cylinder remains normal, but this does not reflect the pressure between the unit slots! So pay attention to this aspect! This post was last edited by yzhms on 2009-2-26 12:10]
To determine if there is a membrane leak, there are specific procedures to follow, and these must be adhered to strictly. Some cell slots can be removed, but the same number of cells must be removed from the front and rear areas of the battery cell (the positive and negative areas with respect to ground voltage).
The monitoring of the center point can also be adjusted via electrical controls; generally, there is a measurement point at each end of a single slot, which may make the adjustment process much less labor-intensive. After changing the membrane last time and driving, at one specific section I had to replace three cell slots in a row; ultimately, there was no other choice but to drive with two fewer cell slots. It was just a minor adjustment, and everything worked fine afterward. Only the situation of compression needs to be considered.
The overflow color of the anode, chlorine purity, voltage, pH and chlorate content in each anode cell, salt content in the cathode alkali – if the membrane is not working well, it needs to be replaced; this is how we do it in our factory.
In the case of membrane leakage, the following phenomena generally occur: 1. The cell voltage is low, with a deviation exceeding 300 mV； 2. The hydrogen content in chlorine will increase, which has an adverse effect on safe production ； 3. In cases of significant leakage, alkali will enter the anode side, where chlorates are formed and this leads to corrosion of the anode, resulting in tank leakage ； 4. Salts in the alkali will increase it ； 5. The voltage at the center point changes.
Membrane leakage is mainly caused by: 1) late coloring of the anode outlet hose and low cell tank voltage (at the start of operation); 2) large fluctuations in acidity at the anode outlet; 3) changes in the color of the anode outlet hose. This post was last edited by limingshuguang on 2009-3-3 13:02
It is possible to determine whether the membrane is leaking based on the following: 1. The color change of the hose at the anode solution outlet of the electrolyzer. 2. The pH value of the anode solution in the electrolyzer increases, with significant fluctuations. 3. The HCl consumption in the electrolyzer is abnormal and rising sharply. 4. Chlorine gas contains more than 0.3% hydrogen. 5. The cell slot voltage is unstable, either too high or too low (±0.1-0.3V). 6. The EDIZA indication is fluctuating and unstable.
Using a differential pressure transmitter to measure the differential pressure should allow for a quick determination of membrane blockage and leakage
Question: Does a change in the pressure in the cell slot relate to the hydraulic press? Is that what you mean? Please provide details as well. Additionally, I haven’t encountered the issue of reducing the number of slot pieces yet; thank you for sharing your experience~~