Dosing device, useful in machine for producing fibrous web from suspension for addition of aluminum ions to first aqueous working fluid e.g. clear water, comprises measuring and control unit that determines quantity of ions in second fluid

摘要

The dosing device comprises a measuring and control unit (140) that determines a quantity of active aluminum ions in a second aqueous working fluid (170). The second aqueous working fluid includes suspension, direct white water, indirect white water, waste water, and clear water. The measuring and control unit comprises an ion selective sensor, which detects quantity of the active aluminum ions. An independent claim is included for a method for dosing aluminum ions.