Analysis of indicators after the new tank is put into operation
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The last edit to this post was made by sunjl1981 on 2013-1-6 at 23:32. There are several aspects related to the performance of the electrolyzer assembled using Asahi Glass’ ion exchange membrane 8031 that are confusing: our electrolyzer is an older model with forced circulation; the current densities for forced circulation and natural circulation are 3.3 KA and 3.0 KA respectively. Brine fed into the tank was not acidified): 1. The purity of chlorine was low during the first approximately 30 hours of operation (96.5%), and it took some time for the purity to rise to around 98%, though it still wasn’t very high. 2. The sodium hypochlorite concentration in the brackish water exiting the tank was relatively high, reaching 3.5 g/L, whereas the sodium chlorate concentration remained low, below 1.0 g/L. Previously, we used DuPont ion exchange membranes and Asahi Glass ion exchange membrane 8031 together in the same cell and operated them in one system, but this phenomenon did not occur in the DuPont ion exchange membrane electrolyzers. After the DuPont ion-exchange membrane electrolyzers were put into operation, the purity of chlorine produced reached 98% right away, and this value continued to increase as the current increased and stabilized. However, the Asahi Glass ion-exchange membrane 8031 electrolyzers, which were operated together in the same system, exhibited the aforementioned phenomenon. I’m very confused; I don’t know if it’s because of our wrong way of using it or if there are other issues I hope experts in the chlor-alkali industry can offer some guidance. # ， ， &
http://bbs.hcbbs.com/thread-147807-1-1.html Some additional content has been added for reference. :handshake Last edited by yzhms on 2008-2-14 18:26 ]
What are the temperature and power delivery speed while driving? When driving, it is essential to ensure that the electrolyte maintains a certain temperature (above 70 degrees). The power supply speed should be adjusted according to the temperature of the tank, and it is also important to check whether the pipe gaskets are properly sealed.
For a newly installed tank, the tank temperature is generally kept above 70 degrees before power is supplied. After power is applied, the tank operates at a low current level during the initial running-in phase, and full load is only reached after eight hours. Regarding the relationship between power delivery speed and slot temperature, we use PLC control; generally, we adjust the parameters first before increasing the current.
Ideal conditions: Current density: Gradually increased to < 4.0 kA/m2. Temperature: >70 oC. Concentration of the catholyte: 28 – 30% NaOH. Concentration of the anolyte: 190 – 220 gpl. Current rate: 0.05–0.06 KA/min. The specific operating conditions are determined by the cell supplier, based on the type of cell used and the membrane employed, in order to optimize performance. This post was last edited by yzhms on 2008-2-15 22:11]
The surface of the current DuPont membrane has been coated in order to increase the rate at which chlorine and hydrogen escape from the membrane surface, to enhance the disturbance caused by these gases on the fluid near the membrane surface, and to prevent excessive concentrations from forming locally on the membrane, which could affect its long-term operation. This post was last edited by yzhms on 2008-2-20 22:29.]