Means for defibrating and sorting pulp in paper and cellulose industry

Abstract

 A means for defibrating and sorting pulp in paper and cellulose industry, comprising a defibrating means (1,2) consisting of a rotor (2) and a stator (1), wherebetween is established a defibrating zone, and of a sorter (3,4) consisting of another rotor (3) and another stator (4), wherebetween is established a sorting zone, and said stator (4) of the sorter being formed to be sieve-like, and said means comprising a pulp feed (6), accept removal (7) and reject removal (8). At present, defibrating and sorting processes have to be carried out using separate apparatus, which is expensive and space-consuming. With the aid of the present invention, the problem is solved in that the angle (α) between the centre-line of the shaft (9) of the rotor (2) of the defibrating means (1,2) and the defibrating zone is 5 to 45° and the angle (β) between the sorting zone and the shaft (9) of the rotor (3) of the sorter (3,4) is 75 to 105°, and that the defibrating and the sorting processes take place in the same pulp space (5).

Description

[0001] The present invention concerns a means for defibrating and sorting pulp in paper and cellulose industry, comprising a defibrating means consisting of a rotor and a stator, and a sorter consisting of another rotor and another stator, wherebetween is established a sort- ing zone, and the stator of said sorter having been formed to be sieve-like, and said means comprising a pulp feed, removal of accept and removal of reject.

[0002] Apparatus in present use are usually separate defibrators and sorters. Also such apparatus exists which both defibrates and sorts simultaneously.

[0003] However, existing technology is embarrassed by numerous problems. One problem is that several units are required, whereby the price is high and much space is needed. Simultaneous defibrating and sorting require a heavy and expensive construction. It is also a fact that simultaneous defibrating and sorting are not controllable. As a rule, defibrating and sorting take place at different consistency.

[0004] The object of the present invention is to provide a means similar to that described above for defibrating and sorting pulp in paper and cellulose industry, but which is not true of current problems. The means of the invention is characterized in that the angle between the centre-line of the rotor shaft and the defibrating zone is 5 to 45°, and the angle between the sorting zone and the sorter rotor shaft is 75 to 105°, and that the defibrating and sorting take place in the same pulp space.

[0005] As advantages of the invention may be mentioned, for instance, that without changing the sorting process the defibrating efficiency can be steplessly regulated. By pre-defibrating, the fibre flocs can be dispersed, whereby only particles which are not fit to be included in the accept pulp are removed. Similarly, the defibrating stage or the sorting stage may, if desired, be cut out from the means. When the speed of rotation range is properly chosen, the fluidizing effect of the defibrator enables efficient sorting in the same consistency range.

[0006] The invention is described in the following in detail by referring to the drawing attached, in which the figure presents the means of the invention for defibrating and sorting pulp.

[0007] In the figure is indicated the stator of the defibrating means by reference numeral 1 and the rotor of the defibrating means by refer­ence numeral 2, said rotor being rotating, as its name indicates. Pulp feed into the space between the stator and the rotor blades of the defibrator takes place through a connector 6. The angle α between the defibrating zone and the shaft 9 is 5 to 45°, preferably 25°. In the defibrating zone the pulp is defibrated and progresses to the sorter established in the same pulp space 5.

[0008] The sorter consists of a rotating rotor 3 and a stator 4, which is made to be sieve-like. The defibrated part of the material passes the sieve 4 and escapes through the accept exit connector 7. That part of the material which does not pass the sieve 4 exits through the reject exit connector 8. Between the rotor 3 and the sieve (stator) 4 is de-fined a so-called sorting zone which establishes an angle β with the shaft 9, this angle being between 75 to 105°, preferably 90°.

[0009] It is obvious to a person skilled in the art that the invention is not confined to the embodiment example presented in the foregoing and that it may be varied within the scope of the claim stated below.

Claims

A means for defibrating and sorting pulp in paper and cellulose industry, comprising a defibrating means (1,2) consisting of a rotor (2) and a stator (1), wherebetween is established a defibrating zone, and of a sorter (3,4) consisting of another rotor (3) and another stator (4), wherebetween is established a sorting zone, and which stator (4) of the sorter is being formed to be sieve-like, and said means comprising a pulp feed (6), accept removal (7), and reject re­moval (8), characterized in that the angle (α) between the centre-line of the shaft (9) of the rotor (2) of the defibrator (1,2) and the defibrating zone is 5 to 45° and the angle (β) between the sorting zone and the shaft (9) of the rotor (3) of the sorter (3,4) is 75 to 105°, and that the defibration and sorting processes take place in the same pulp space (5).

Drawing