Debarking (lumber)

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Debarker machine Debarker.jpg
Debarker machine
Manually decorticated trunk of a spruce as protection to bark beetles Fichtenstamm entrindet.jpg
Manually decorticated trunk of a spruce as protection to bark beetles

Debarking is the process of removing bark from wood. Traditional debarking is conducted in order to create a fence post or fence stake which would then go on to be pointed before being planted. [1] Debarking can occur naturally during powerful tornadoes. [2]

Contents

Process

Debarking generally involves the use of industrial machinery into which the log or stake is placed. [3] These machines can be either stationary or portable. Generally they are powered by hydraulic motors but can also be driven by a power take-off. The log or stake is then pressed against blades or knives which remove the bark while the log is turned to ensure the removal of bark from all around the log. Debarking can also take place by hand, although this can be very time consuming and may not be suitable for large volumes. [4]

Side-streams from debarking

Bark is the usual side-stream produced during log debarking. In several wood related industries, such as plywood, veneer and laminated veneer industries, the logs, before debarking them, are submerged in warm water to ease the debarking process [5] . The process conditions (temperature and time) depend on the country, company, wood species and their properties [5] [6] . In some countries, such as Finland, the water used in this process is discarded, but studies prove that it accumulates several valuable compounds, such as glucosides, proanthocyanidins and phenolics [7] . This water is a promising side-stream that should be further studied.

See also

Related Research Articles

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<span class="mw-page-title-main">Wood</span> Fibrous material from trees or other plants

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Tanning, or hide tanning, is the process of treating skins and hides of animals to produce leather. A tannery is the place where the skins are processed.

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<i>Betula alleghaniensis</i> Species of flowering plant in the birch family Betulaceae

Betula alleghaniensis, the yellow birch, golden birch, or swamp birch, is a large tree and an important lumber species of birch native to northeastern North America. Its vernacular names refer to the golden color of the tree's bark. In the past its scientific name was Betula lutea.

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<span class="mw-page-title-main">European spruce bark beetle</span> Species of beetle

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A hydraulic debarker is a machine removing bark from wooden logs by the use of water under a pressure of 700 kilopascals or greater. Hydraulic debarking can reduce soil and rock content of bark, but may increase the water content. Debarking water may be recycled after effective settling, but suspended solids may increase wear on high-pressure pumps. Hydraulic debarking has declined where water quality problems have arisen.

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<span class="mw-page-title-main">Molded plywood</span>

Molded plywood is the term for two- or three-dimensionally shaped products from multiple veneer layers that are glued together through heat and pressure in a pressing tool. The veneer layers are arranged crosswise at an angle of 90 degrees. Molded wood is used for flat furniture components such as seats, backrests and seat shells. When the veneer layers are arranged in the same direction, it is called laminated wood. It is used for armrests and chair frames. After pressing, the blanks are processed mechanically. A particular feature is the ability to produce different variations of shapes from the blanks. Due to its immense strength and low weight, molded wood is particularly suitable for interior decoration, seating furniture, bed slats, skateboards and vehicle construction.

References

  1. Debarkers. Energy Online Expo.
  2. Adams, Dave K. (2007). The structural engineer's professional training manual. McGraw-Hill Professional. p. 193. ISBN   978-0-07-148107-6 . Retrieved 24 May 2011.
  3. Leavengood, Scott. "Western Juniper Debarking Project" (PDF). Oregon State University. Retrieved April 14, 2011.
  4. "Chapter 10 - Debarking". Wood Harvesting with Hand Tools - An Illustrated Training Manual. International Labor Organization. 1987. p. 128. ISBN   9221062171. OCLC   816745408.
  5. 1 2 Rohumaa, Anti; Yamamoto, Akio; Hunt, Christopher Glaab; Frihart, Charles Richard; Hughes, Mark; Kers, Jaan (2016-05-11). "Effect of Log Soaking and the Temperature of Peeling on the Properties of Rotary-Cut Birch (Betula pendula Roth) Veneer Bonded with Phenol-Formaldehyde Adhesive". BioResources. 11 (3). doi:10.15376/biores.11.3.5829-5838. ISSN   1930-2126.
  6. Dupleix, Anna; Denaud, Louis; Bléron, Laurent; Marchal, Rémy; Hughes, Mark (2013). "The effect of log heating temperature on the peeling process and veneer quality: beech, birch, and spruce case studies". European Journal of Wood and Wood Products. 71 (2): 163–171. doi:10.1007/s00107-012-0656-1.
  7. Barbero-López, Aitor; Vek, Viljem; Poljanšek, Ida; Virjamo, Virpi; López-Gómez, Yeray Manuel; Sainio, Tuomo; Humar, Miha; Oven, Primož; Haapala, Antti (2022-05-01). "Characterisation, Recovery and Activity of Hydrophobic Compounds in Norway Spruce Log Soaking Pit Water: Could they be Used in Wood Preservative Formulations?". Waste and Biomass Valorization. 13 (5): 2553–2564. doi:10.1007/s12649-022-01676-2. ISSN   1877-265X.