Further considerations of magnetic deinking for wastepaper recycling mills

Magnetic de-inking has been shown to be an efficient process for the removal of certain toner particles from mixed office waste (MOW) furnishes. It is possible to achieve a dirt removal of 96% with the WHIMS (wet high intensity magnetic separator) if all toner particles present in the furnish are at least paramagnetic. However, the recycled MOW has a variety of toner particles thai vary from non-magnetic to ferromagnetic and , under these circumstance, it may be necessary to combine flotation with WHIMS in order to achieve a satisfactory level of dirt removal. On the other hand, flotation may not be necessary if agglomeration of non-magnetic and magnetic toner particles can be accomplished. In this regard, conditions for toner agglomeration have been examined and the toner agglomeration characterized. Specifically, the magnetic susceptibility of such aggregates has been measured in order to facilitate efficient magnetic de-inking for wastepaper recycle mills.