The function of the saltwater sump
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This post was last edited by sunjl1981 on 2013-1-6 at 21:29. Our process includes a high-level tank, but it is only used during startup and shutdown; it is not utilized during normal operation. May I ask which company uses a head tank to supply liquid to its electrolyzers? What is the function of a saltwater sump? During unplanned shutdowns, is the brine used for filling and submerging the electrolyzer also provided by the brine sump? What factors determine the volume of a sump? # hcbbs
In my understanding, electrolyzers that operate on a natural circulation principle use a sump to supply liquid; this results in a smaller pressure difference, and thus there is no need for a sump when shutting down the system to flush out chlorates or when refilling liquid during startup. The volume of the sump should be as large as possible, provided that it offers a good cost-performance ratio; this way, in the event of a failure in the anode or cathode pumps, there will be sufficient time to switch to another pump, thereby avoiding disruptions to production
At Wood, Chlorine Engineering, and Beihua Machinery, natural circulation cells all come equipped with high-level tanks for saline and alkaline solutions. During operation, these solutions flow into the cells due to the pressure difference; therefore, the high-level tanks must be placed at an appropriate height to ensure that the saline and alkaline solutions can enter the cells smoothly, overcoming the pressures in the anode and cathode chambers of the cells. Furthermore, during a power outage across the entire plant, the backup power supply often fails to be activated in time; therefore, making the high-level tank larger provides a certain margin for filling it in case of a power outage
The electrolyzers provided to us by the British side are naturally circulating electrolyzers that use pumps for liquid supply, with the brine sump being used only during startup and shutdown. In my opinion, since a high-level tank is available for supplying liquid, wouldn’t the flow rate and pressure fluctuations be more stable? 2# lujianfei79
What kind of electrolyzer are you using? It’s only for starting and stopping the process – isn’t that necessary?
For the Ineos electrolyzer, the construction has just begun. However, based on the material flow diagrams and PID diagrams provided by the foreigners, it seems that the brine sump is indeed used only during startup and shutdown procedures; during normal operation, the brine does not pass through this sump but is directly pumped to the electrolyzer. Is this reasonable? 5# *ou*ngzhe
Personally, I think it’s unreasonable; during normal production, liquid can be pumped in directly, right? Isn’t the same thing true when filling the system during startup or shutdown? It would be more reasonable either to remove the high-level tank, or to allow brine to flow into the electrolytic cell from the high-level tank while the machine is not in operation
When driving normally, a high-level tank is used, which allows the steady supply of brine to the electrolyzer through static pressure. During an emergency stop, the amount of salt water in the high-level tank can ensure sufficient filling for the electrolyzer. Using a sump to feed brine is smoother than using a pump.
The functions have been explained very clearly by the moderators; it’s better to go with a larger size!
Hehe, first of all, it’s necessary to ensure that the electrolyzer is fully filled and submerged during shutdown; even during normal operation, a head tank is used. Shouldn’t the capacity required be significantly higher than these conditions allow? But it’s too large; the cost of manufacturing such equipment is high, and it’s also a waste. Moreover, if it’s placed at a high height, higher requirements are placed on the pile foundations. Therefore, I would like to ask what the appropriate size range is. Could you please provide an answer? 9# liuyan126595
In my opinion, the functions of the high-level tank are as follows: 1. It is put into use during operation to provide the power necessary for material transfer, and it ensures stable pressure through level control; this is very important for high-electrolyte-density natural-circulation electrolyzers. 2. In the event of an emergency stop, the brine in the high-level tank can displace the chlorine trapped in the electrolyzer; this design takes into account the situation where no power supply is available.