For S 25 KV - 25 ... - IL dispersing elements. Allows inline operation mode, see UTL 25. Batch operation: DK 25.11 is mounted around the dispersing element. The DK 25.11 must be at a lower elevation than the surface of the liquid during operation. With this operating mode, no air is drawn in as a result of turbulence in the vessel. For S 25 KV - 25 ... - IL dispersing elements. Allows inline operation mode, see UTL 25. Batch operation: DK 25.11 is mounted around the dispersing element. The DK 25.11 must be at a lower elevation than the surface of the liquid during operation. With this operating mode, no air is drawn in as a result of turbulence in the vessel.