Method of treating waste paper for obtaining a stock suspension for the production of new paper and apparatus for the performance of the aforesaid method

An apparatus for treating waste paper in order to obtain a stock suspension for the fabrication of new paper, comprising:

• a stock slusher for defibering waste paper within which the waste paper is mixed with water in order to form a stock suspension;
• a sorting apparatus operatively connected with said stock slusher;
• said sorting apparatus incorporating means for sorting the stock suspension formed in the stock slusher into heavy contaminants, floatable contaminants, large-surface contaminants, not completely defibered paper pieces and fibers which can be used as good stock;
• the sorting means containing structure for separating out the contaminants;
• an additional defibering means for receiving the not completely defibered paper pieces;
• and
• means for receiving the fibers which are ready to be directly used and which have been separated out as good stock so that such received fibers can be directly employed for the paper fabrication.

A method of treating waste paper for obtaining a stock suspension for fabricating new paper, comprising the steps of:

• forming a stock suspension in a stock slusher by infeeding waste paper and water into said stock slusher;
• said stock suspension containing contaminants and incompletely defibered paper parts;
• withdrawing and removing in succession, outside of the stock slusher, the contaminants from the flow of the stock suspension in the form of heavy particles, floatable substances and large-surface contaminants which are insoluble in water;
• removing fibers from the stock suspension;
• removing from the remainder of the suspension incompletely defibered paper parts;
• further defibering the removed incompletely defibered paper parts;
• and
• feeding the fibers which have been removed from the stock suspension together with the fibers obtained from the incompletely defibered paper parts as good stock for further processing into paper.