Metso Paper Inc.

Valmet Corporation

Valmet Paper Machinery Inc.

Oy Tampella Ab

Valment Corporation

Valmet Technologies, Inc.

Timo Vuorinen

Jouko Hautala

Juhani Valli

Ismo Hourula

Jorma Pet&auml;jist&ouml;

Jorma Petajisto

Tuomo Aho

A fiber mass suspension is produced by mixing together a fiber material (FM) and water (W) in a pulper (). The formed fiber mass suspension is divided into an accept fraction and a reject fraction. The reject fraction is supplied continuously to a first secondary pulper () for further screening and defibring. The accept fraction formed in the first secondary pulper () is supplied continuously for further processing and the reject fraction formed in the first secondary pulper () is supplied continuously to a second secondary pulper () for further processing. The accept fraction formed in the second secondary pulper () is supplied continuously for further processing.

Apparatus and method for manufacturing fibre mass suspension

An apparatus for separating fibers from reject material produced in the manufacture of recycled pulp. The apparatus comprises a rotating reject cylinder provided with openings, to one end of which the reject material is fed and from the other end of which it is discharged, water nozzles for feeding water to the reject material in the cylinder to separate fibers from it, a collecting basin for recovering water and the fibers separated with it, and discharge channels connected with the collecting basin, and means for discharging fibrous water and light and heavy particles from the collecting basin. The collecting basin is formed of two basin structures at least partly within each other and connected with each other.

Apparatus for separating fibers from reject material

The invention relates to a method and a screen for screening two or more pulp mixtures with different roughness. The screen comprises a first screen cylinder and a second screen cylinder. A coarse first pulp mixture is fed into the inlet end of the first screen cylinder, and a second, less coarse pulp mixture is supplied to the second screen cylinder. The pulp mixtures are screened by means of a screen surface of the screen cylinders into accept that passes apertures provided in the screen surface and reject that does not pass the apertures. The accept from the second cylinder is conveyed by means of a guide tube provided between the cylinders towards the inlet end of the first cylinder and it is finally mixed with the first pulp mixture. The accept from the first and the second pulp mixture passes the screen surface of the first screen cylinder.

Method and screen for screening at least two pulp mixtures

The invention relates to a method for controlling a multi-step screening apparatus (,), the method comprising controlling other accept, reject and dilution flows in relation to the flow measured in the accept channel (,) of the first screening step (,). Thus a simpler control unit (,) can be used and accept of higher quality can be obtained than before. The invention further relates to an apparatus for controlling a multi-step screening apparatus (,), said apparatus comprising a control unit (,) arranged to measure the flows of all accept, reject and dilution water channels (,) and to adjust the flow of the other channels on the basis of the flow of the accept channel of the first step.

Method and arrangement for controlling a multi-phase screening apparatus

A method and apparatus for controlling a multi-step screening apparatus (1) controls other accept, reject and dilution flows in relation to the flow measured in the accept channel (7a) of the first screening step (3a). Thus a simpler control unit (9) can be used and accept of higher quality can be obtained than before. The apparatus has a control unit (9) aranged to measure the flows of all accept, reject and dilution water channels (7a-7c, 5a, 5b, 11a, 11b) and to adjust the flow of the other channels on the basis of the flow of the accept channel of the first step.

Method for controlling a multi-phase screening apparatus

Mixing device in pulping

In a method and apparatus for removing impurities from paper pulp, the pulping space enclosed by a solid jacket is divided into a primary and a secondary space by means of a partition wall. Both the primary and the secondary space are provided with separate rotor units and perforated screen plates in connection with rotor units. The paper pulp to be purified is conducted into the primary space and a connection between the primary and secondary spaces is arranged within the partition wall which allows for continuous use of both spaces for removing impurities.

Growing community of inventors

Tampere, Finland

Timo Vuorinen