Sometimes we encounter situations where weak base anion exchange resins agglomerate due to silicone polymers. This will cause short-range operation and high conductivity of the weak base anion resin and will not be able to backwash normally. When the resin column is opened and the sample is taken out, the resin particles will condense together and even some sticky substances will be seen. This article mainly explains the causes of such problems and some methods to solve these problems.
Many water treatment desalination systems generally use strong alkali resins in addition to weak alkali resins. In order to minimize the amount of alkali when regenerating the resin, regenerating is a commonly used method. The waste alkali regenerated from the strong base resin is used to regenerate the weak base resin. Due to the high regeneration efficiency of the weak base resin, even the waste alkali can restore the performance of the resin.
The most basic of the application regeneration method is to confirm that the regenerated liquid from the strong alkali resin is discharged into the sewage before the application. Usually, the first 1/3 of the regenerated liquid from the strong base anion resin is discharged into the trench. If the silicon concentration is high when the regeneration starts, this will cause the above problems on the weakly alkaline resin.
First of all, the diversified operating conditions of the strong alkali resin will cause fluctuations in the silicon concentration, including the concentration of the alkali regeneration solution, the regeneration temperature, and the use of a new strong alkali anion resin. Under normal circumstances, the amount of recycled waste alkali discharged into the sewage should be increased before applying it. The stratified bed strong base anion resin and weak base anion resin are regenerated at the same low concentration of alkali and run at the same flow rate, so the possibility of silicon precipitation will gradually decrease.
Finally, the weak alkaline anion resin needs to be cleaned. Hot alkaline soaking helps to remove the silicon polymer and allows continuous operation. In some special cases, the weak base anion resin may need to be replaced.
Note: The caking of weak base resin may be due to organic matter or a combination of organic matter and silicon.