Waste wood
As waste wood means the wood residues from primary production, the impact of the forest, in the treatment and processing of wood in the industry, as well as in construction and mining are incurred.
This includes forest residues and industrial residues , untreated wood residues from construction sites , mines (scaffolding boards, support material, etc.). This can be processed further without any problems.
A distinction must be made between residual wood and waste wood (also used wood ), as this is wood that has already been used in some way. This can only be partially recycled; problematic wood waste includes wood treated with wood preservatives , coated wood waste and mixtures of problematic wood waste and other wood.
Occasionally, however, waste wood is also referred to as residual wood.
Residual forest wood
As forest residues is known in the forestry that the forest residues and thinnings wood residues contained.
Logging residues is composed of components of the impact overburden: stem wood (Stubbe wood, stalk wood) → stump , non-solid wood ( rice wood ), as well as tree tops , X-timber (not usable compact wood and inferior stem parts, stock lazy butt logs , and are transmitted, felled trees).
Forestry Economically designated forest residues when specified in Derbholz cubic meters the amount of non-recyclable Derb wood and the disclosure in tree wood cubic meters are not usable amount of standing timber and brushwood. In principle, forest residues are to be distinguished from industrial residues, which include all by-products, residues and waste that occur in the woodworking and processing industry.
use
Some of it can be used as industrial wood and it is also processed into fascines . Attempts have also been made to obtain fuel from residual forest wood. → Choren Industries
Due to the increased demand for renewable raw materials , especially in the field of energy wood , the residual forest wood is increasingly being used. Often attached sticks and even leaves are also removed. In the latter case in particular, the nutrients that are otherwise released when rotting are removed from the forest. Depending on the level of nutrient buffering, there may be a shortage of supply and subsequent reduced yields.
In Germany, many forest offices issue reading permits to interested private individuals. They are allowed to take reading wood on the assigned part of a playing surface , especially for the use of firewood . In addition, residual forest wood is used to produce wood pellets or is chopped and sold as bark mulch .
In Scandinavia , where the per capita forest area is several times higher than in Germany, machine bundling systems are in use, which after logging and removing the usable trunks also collect the remaining branch material. The material is tied into packages with an energy content of around one megawatt hour (MWh), which are used for the energetic use of biomass ( bioenergy ), which is very widespread in Scandinavia .
Industrial waste wood
All wood that accumulates as by-products, residues and waste in the woodworking and processing industry is referred to as industrial waste wood. These arise during the production of the desired main products as well as with various by-products of the wood-based materials industry ( chipboard and others) and are primarily available for energetic use. Part of the waste wood and especially the sawing by-products also fall into this group of raw materials. Section 2 of the Waste Wood Ordinance defines industrial waste wood as wood residues occurring in woodworking or processing companies as well as composite materials with a predominant wood content (more than 50 percent by mass) .
Industrial waste wood in its entirety, a fraction of 50 percent or more of the total processed can logs make up, the average yield of the sawmills of sawn timber is about 65 to 70 percent. The rest is used as industrial waste wood. In Germany, around eight to ten million tons are produced each year, around a third of which can be used for energy.
composition
According to its origin from the wood processing industry, industrial waste wood consists primarily of wood residues in the form of wood chips , wood cuttings, rinds , splinters , pieces of bark , shavings and wood dust.
Wood slabs are created when round logs are cut, while scrap or sections are generated as waste when logs are cut to length. Chips are also produced when processing raw wood and wood-based materials and, together with the rinds and sections, can be processed into wood chips for material and energy use. Wood chips and grinding dust are also collected and can be used both materially (chipboard) and energetically ( wood pellets ).
use
Industrial waste wood is mostly used energetically as fuel , although the use of many of these materials in a material use, especially in the wood-based materials industry, means great added value . The quantities of sawmill by-products that occur in Germany (as part of the industrial waste wood) are practically completely used and cover a good third of the raw material requirements of the wood-based materials industry. The proportion of sawmill by-products in the wood of chipboard is around 50 percent, with medium-density fibreboard (MDF) it is 70 percent. The wood pulp and wood pulp industries process comparatively small amounts.
The need for residual wood for pellet production and wood chips for energy generation has been increasing sharply for several years, thus increasing the demand for this raw material. Since these are by- products , the supply of saw-by-products depends primarily on the demand for sawn timber. An increase in demand, as is currently the case due to increased energetic use, can lead to a shortage with price increases, so that instead of sawing by-products, other raw material sources such as other industrial waste wood or residual forest wood are increasingly used.
In contrast to other industrial waste wood, bark residues can only seldom be used as a material due to their high water content and contamination. Some of them are used to make bark compost , which is used as a mulch material in gardening and landscaping. Another part is burned in appropriate combustion systems.
literature
- Lignocellulose plants produced by forestry. In: Martin Kaltschmitt , Hans Hartmann, Hermann Hofbauer (Hrsg.): Energy from biomass. Basics, techniques and procedures. Springer Verlag, Berlin and Heidelberg 2009, ISBN 978-3-540-85094-6 , pp. 75-88.
- Industrial waste wood . In: Martin Kaltschmitt, Hans Hartmann, Hermann Hofbauer (Hrsg.): Energy from biomass. Basics, techniques and procedures . Springer Verlag, Berlin / Heidelberg 2009, ISBN 978-3-540-85094-6 , pp. 141-143 .
Individual evidence
- ↑ Herwig Hulpke, Herbert Koch Reinhard Nießner (ed.): RÖMPP Lexicon Environment. 2nd edition, Thieme Verlag, 2000, ISBN 3-13-736502-3 , p. 60.
- ^ Gerhard Stinglwagner, Ilse Haseder, Reinhold Erlbeck: Das Kosmos Wald- und Forstlexikon. 5th edition, Kosmos, Stuttgart 2016, ISBN 978-3-440-15524-0 .
- ↑ The forest is swept on franzjosefadrian.com, accessed on January 19, 2017.
- ↑ Biomass use and nutrient extraction on waldwissen.net, accessed on April 21, 2011.
- ↑ a b c d e industrial waste wood. In: Martin Kaltschmitt , Hans Hartmann, Hermann Hofbauer (Hrsg.): Energy from biomass. Basics, techniques and procedures. Springer Verlag, Berlin / Heidelberg 2009, ISBN 978-3-540-85094-6 , pp. 141-143.
- ↑ Torsten Leps (Rosenheim University of Applied Sciences): Wood-based materials - state of the art, opportunities, developments and trends. Presentation at the CARMEN Forum, March 30, 2009, online at yumpu.com, accessed on January 18, 2017.