Patent ID: 8480855
Filing Date: 2013-07-09
Classification: D21H

Abstract:
1. A precipitation reactor suitable for precipitating mineral particles onto fibers, said precipitation reactor comprising at least one gas feeding device adapted to supply a gas containing a precipitant substance to a gas space of the precipitation reactor; at least one feeding device adapted to supply fiber material and a reactive mineral substance, either separately or together as a fiber suspension, at least one disintegration device adapted to receive said fiber material and reactive mineral substance from said feeding device, said disintegration device capable of disintegrating the fiber material and reactive mineral substance into small solid particles or liquid fractions and discharging them into said gas space, said disintegration device being further capable of activating the fiber material so that its ability to bind with itself and precipitated mineral substances is increased prior to discharge into said gas space, wherein said disintegration device is a through-flow mixer operating on the principle of an impact mill, such that the through-flow mixer is fitted in a top section of the gas space, the through-flow mixer has predominantly an open outermost ring which allows the fiber suspension having flowed through the through-flow mixer to be discharged in different directions directly into said gas space, and said device for removing the treated fiber suspension from the precipitation reactor is located at a bottom section of the precipitation reactor, at least one device for discharging a treated fiber suspension containing the fiber material and a precipitated mineral substance from the precipitation reactor, such that in operation a dwell-time of the fiber material in said disintegration device is less than 10 seconds.