摘要:
A sieve for sorting fiber suspensions, symmetrical in relation to an axis, with an inflow side for the fiber suspension to be sorted and an opposite outflow side. This sieve is useful for pressure sorting machines having a rotor that may be rotated around the axis of the sieve and that is provided with profiled elements around the inflow side of the sieve in order to generate positive and negative pressure pulses in the fiber suspension that is to be sorted. The inflow side of the sieve has grooves approximately parallel to the axis of the sieve that follow each other in the circumferential direction of the sieve. A through-channel opens into each groove. The grooves are delimited by a front and a rear side wall, seen in the direction of rotation of the profiled elements. In order to increase the capacity of the pressure sorting machine, the grooves have an approximately V-shaped cross section in a section perpendicular to the axis of the sieve and the front sidewall of the groove forms an angle from approximately 40.degree. to approximately 70.degree. with the circumference of the sieve.
摘要:
A size press having at least one coating nip avoids splashing of the sizing or equivalent coating agent by leading the web to be treated through said nip. Coating supply apparatus supplies coating pools at the nip entrance between a coating roller and the web entering said nip. The coating supply apparatus includes filling pieces in the nip entrance, placed in the coating pool in operating position. The filing pieces consist of permeable, porous, or perforated material and extend along the entire width of the web. The filling pieces suppress the coating pools and prevent or, at least, essentially decrease, the splashing of the coating agent.
摘要:
The subject invention concerns a novel enzymatic process for bleaching kraft pulp. Specifically, novel enzymes, designated rLDM.TM., and other ligninolytic enzymes present in the extracellular growth medium from a fermentation of Phanerochaete chrysosporium, are used to bleach kraft pulp to a desired lighter color.
摘要:
Coating apparatus includes three coating rollers, in a closed group, forming two coating nips with each other. First coating supply apparatus is provided on the first coating roller, followed by knife or doctor coating apparatus. Second coating supply apparatus is provided on the second roller after the first nip, followed by knife or doctor coating apparatus. After the second roller, the paper web runs through a second nip formed by the second roller and a third coating roller. The coated web is released from the third coating roller and transferred to drying apparatus, for example. If necessary, heating apparatus is provided at the first and second coating rollers for drying the web and the coating agents by heat radiation without contact with the web.
摘要:
A method and apparatus for high speed application of sizing compositions in which there is a pair of oppositely rotating rolls forming a coating nip therebetween through which a paper web to be sized is directed. Sizing composition is delivered to the nip in sufficient quantity to form a pond of sizing composition above the nip. The invention is particularly concerned with reducing the effects of translational energy which is transmitted into the pond from the rolls by providing at least one flexible baffle member which extends into the pond on opposite sides of the paper web into proximity with the nip. The baffle member should be sufficiently long to absorb translational energy which would otherwise be absorbed by the pond of sizing material.
摘要:
A cylindrical rotating thickening device including an axial core, a plurality of longitudinally extending spaced apart support ribs extending radially from the axial core, and a shell surrounding the support ribs and supported thereon. The shell includes a plurality of longitudinally extending spaced apart grooves, and a perforated deck surrounding and supported on the shell. The deck includes a plurality of closely adjacent deck segments, and each deck segment includes a leading edge and a trailing edge. Each deck segment further includes an integral bar attached to the leading edge and received in the shell groove, and a plurality of fasteners for securing the bar to the shell.
摘要:
Paper pulp is added to a stain solution. The stain solution and pulp fibers are mixed to form a slurry. Samples are removed from the slurry and are admixed with dilution water and a bleach. Then, the fibers are moved into a flow cell where they are subjected to a light source adapted to stimulate fluorescence from the stained pulp fiber. Before the fiber slurry enters the flow cell it is mixed with a dilution water of bleach to reduce background fluorescence. The fluorescent light is collimated and directed through a dichroic filter onto a fluorescence splitting dichroic filter.
摘要:
Method and an apparatus for controlling the production of thermomechanical pulp meter chips by metering elements (9, 10) into a feed chest (2), and by feed elements (3, 7) connected to the feed chest feeds chips for refinement between thermomechanical pulp refining discs (5). Water is added to the chips prior to feeding the chips between the discs (5). Moisture content of the thermomechanical pulp is measured after the thermomechanical pulp refiner at least in a semicontinuous fashion by at least one measurement device (21, 22, 23, 24) operating on-line, and on the basis of measured moisture content, the quantity of chips and water to be metered is controlled so as to regulate the moisture content to a desired level of having a constant value by, e.g., increasing the volume of metered chips and simultaneously decreasing the quantity of fed water for an increasing trend of moisture content, and correspondingly, applying an opposite strategy to counter a decreasing trend of moisture content. The implementation provides for a consistent quality of thermomechanical pulp.
摘要:
Foam applicators having specific lip configurations and substrate orientation, used for applying foamed treating compositions to substrates, including rapidly moving paper, provide uniform distribution of treating agent onto the substrate.
摘要:
Surface-treated paper in the form of a continuous web is made by first roughening a base paper which serves as a starting material on the sides to be treated. The roughened web is then passed over and in direct contact with a discharge slot from a container that extends across the web and through which the desired treatment liquid is flowed onto the surface of the web, and the surface-treated paper is then dried and finally reeled.