Acid addition issue in electrolyzer
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This post was last edited by sunjl1981 on 2013-1-6 at 22:40. After using an ion membrane electrolyzer for a certain period of time, its current efficiency decreases. To neutralize the OH ions that migrate back to the cathode, acid needs to be added. I wonder: the amount of acid we add is not that much, right? There’s no need for us to add it in small amounts every hour, as some people do…… The cucumbers have probably already cooled down by now. I also want to ask that once acid is added, it should be taken into account when calculating the total flow rate at the anode, right? # + +
The flow rate added is extremely small, and can be disregarded compared to the total flow rate of the saline solution. . .
Add acid with great care; it can be added slowly while monitoring the process. The acid flow is measured in liters, while the brine flow is measured in cubic meters; for the brine flow, the acid flow is negligible
Acid must be added slowly; this is essential. Adding acid in large amounts suddenly is strictly prohibited. Moreover, the change in current efficiency is very slow, and it basically has no impact on the operations carried out by DCS operators. However, the amount of acid added changes significantly when the current level is increased or decreased; over time, one learns to recognize this pattern.
Reply to 4# Galaxy: It’s absolutely not allowed to increase the value suddenly. We do have certain time limits in place for this, as there were rules in the past that required a half-hour before reaching a certain level. We think there’s no need for such slowness – after all, what amount of traffic is generated when so many slots are added at once? It’s sufficient to increase it gradually; there’s no need to set a requirement of one hour or several dozen minutes before reaching a certain value
Reply to 1# Man’s True Nature: The flow rate associated with acid addition is included in the total anode flow rate; this should have been specified during the design of the DCS. This data is needed when calculating current efficiency. Although its impact on the numerical values can be ignored, the flow rate of the acid added can provide a preliminary indication of the level and trend of current efficiency. The amount of acid added must be controlled carefully – it should neither be too much nor too little. By referring to the dissolution equilibrium diagram of chlorine in water, it is possible to determine how to control the pH value when adding acid. Adding acid to the electrolyzer can reduce the amount of acid needed during dechlorination; it also helps to lower the chlorate content in the brine, as well as the oxygen content in chlorine gas.
We have an online pH meter, which is used to control the flow rate of acid addition.
Reply to 7# liujiangfei: I know; we have it here too. What I mean is the control of the acid addition rate at the beginning
Care must be taken when adding acid to the electrolyzer. Once, our company added too much acid, which caused the shutdown of individual electrolyzers in a chain reaction; there were significant changes in both the chlorine pressure and the cell voltage. However, once the car was started again, everything was fine; in fact, the battery voltage dropped by about 3V. What a stroke of luck.
Reply to 9# tangyong421: What was the sequence of events that led to you stopping production due to adding too much acid?
Friends on the 9th floor, is there a linkage between the acid flow rate and the electrolyzer? (Or in other words, there is a linkage between acidity and the electrolyzer.) To what level should the acidity be increased? Is there a 3V voltage drop when starting the engine for the first time? What groove type? Could you be more specific? To wealth