Abstract: SC paper which is produced from a fibrous stock suspension containing fibers which are partially loaded with ash is characterized in that the ash content in the SC fiber web which was produced from the fibrous stock suspension is higher than 35%, preferably higher than 39%. Newsprint which is produced from a fibrous stock suspension containing fibers which are partially loaded with ash is characterized in that the ash content in the newsprint fiber web which was produced from the fibrous stock suspension is higher than 15%, preferably higher than 19%. Wood-free, uncoated paper which is produced from a fibrous stock suspension containing fibers which are partially loaded with ash is characterized in that the ash content of the wood-free, uncoated fiber web which was produced from the fibrous stock suspension is higher than 15%, preferably higher than 19%.

Abstract: The present invention relates to a method and a paper machine for producing a calendered paper web. The method includes the step of partially loading with ash a plurality of fibers of a fibrous stock suspension. The paper machine for the production of a calendered paper web from a fibrous stock suspension including a plurality of fibers which are partially loaded with ash includes a first device for loading a fibrous stock suspension with ash. The first device can include a first static mixer, a preparation unit for adding calcium oxide or calcium hydroxide, a press or a dewatering screw, an equalizing reactor or an equalizing screw, a container serving as a crystallizer, a second static mixer, and a carbon dioxide storage tank or a second device for recovering carbon dioxide.

Abstract: A machine for producing a fibrous web is characterized in that a measuring arrangement for measuring the ash content is mounted inside the machine, particularly inside the wire section, the press section, the drying section or after the drying section in front of a calendar. This measuring arrangement is connected, via a signal line, to a controller that is mounted inside a device for producing the fibrous material suspension.

Abstract: A sheet forming system of a paper or cardboard machine. A headbox includes a headbox nozzle with to laterally extending side panels and first and second nozzle walls extending along a width of the machine. First and second screens converge in a region adjacent the headbox nozzle. At least two guide mechanisms, each having a guide surface, guide the first and second screens in the region. At least one support mechanism supports at least a portion of one of the first and second nozzle walls against said guide surface of at least one of said at least two guide mechanisms.

Abstract: Process for cleaning or maintaining the cleanliness of a low-consistency branch of a stock density-regulated headbox system including a constant part of a paper or cardboard machine having at least one high-consistency branch and one low-consistency branch, possibly sectioned. The final concentration output by the headbox onto a wire or between two wires is determined by a mixing ratio of high-concentration and low-concentration suspension flows. The process includes supplying the low-consistency branch with an increased content of solid particles. Headbox system including a constant part of a paper or cardboard machine, having a stock density regulation that is sectioned across the machine width by variably mixing a high-consistency suspension and a low-consistency suspension, with a high-consistency branch and a low-consistency branch. The headbox system includes at least one supply to the low-consistency branch for introducing solid particle contents into the suspension flow.