Other

Valmet Corporation

M-real Oyj

Kai Vikman

Rauno Verner Rantanen

The purpose of this invention is to provide a method and an apparatus for producing thermomechanical fibers using less energy per ton that has previously been required for similar type of production. The invention is based in that at least two refiners are combined so that mixture of chips, water and steam is first fed into a first refiner wherein the chips are broken up and the mass flow from the first refiner is then fed into the second refiner for breaking the fibers to final freeness level. The mass flow of steam and fibers is fed forwards at least in the first refiner by the rotational energy of the refiner rotor so that essentially no flowback of the steam occurs. The mass flow exciting the first refiner is fed completely to the second refiner and no steam is extracted from the mass flow before the second refiner.

Method and apparatus for producing mechanical fibers

A method and apparatus for two-side coating of a light base weight printing paper web containing mechanical pulp or recycled fiber. The first side of a web (,) is coated in a first coating station (,), the coating applied to the first side is dried at least partially in a first dryer unit (,). The second side of the web (,) is coated subsequent to the drying of the first side in a second coating station (,), and the coating applied to the second side is dried at least partially in a second dryer unit (,). Both coatings are formed by applying a required amount of coating mix onto the perimeter of respective soft film-coating rolls (,) and subsequently transferring the coat film to the web (,) in a nip (N,) formed between a respective backing roll (,) and the respective soft film-coating roll (,).

Method for two-side coating of a thin printing paper web containing mechanical pulp or recycled fiber

A method and apparatus for two-side coating of a light base weight printing paper web containing mechanical pulp or recycled fiber. The first side of a web (5) is coated in a first coating station (1), the coating applied to the first side is dried at least partially in a first dryer unit (3). The second side of the web (5) is coated subsequent to the drying of the first side in a second coating station (2), and the coating applied to the second side is dried at least partially in a second dryer unit (4). Both coatings are formed by applying a required amount of coating mix onto the perimeter of respective soft film-coating rolls (22) and subsequently transferring the coat film to the web (5) in a nip (N.sub.1) formed between a respective backing roll (24) and the respective soft film-coating roll (22).

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Kirkniemi, Finland

Kai Vikman