old wood

from Wikipedia, the free encyclopedia
Shredded waste wood

As waste wood is called Wood that had been already supplied to a purpose and as waste for disposal of waste wood or as a secondary raw material is ready. Waste wood can be recycled materially, for example in the wood-based materials industry for chipboard or thermally.

definition

According to § 2 No. 1 of the German Ordinance on Requirements for the Recovery and Disposal of Waste Wood ( Waste Wood Ordinance ), waste wood is " industrial waste wood and used wood , insofar as this is waste within the meaning of Article 3, Paragraph 1 of the Recycling Management and Waste Act (KrWG). is ". According to this regulation, waste within the meaning of the Waste Act is "all movable objects [...] whose owner discards, wants to or has to discard."

Section 2 no. 2 and no. 3 AltHolzV differentiates industrial wood and utility wood. Industrial waste wood is wood residues that occur in woodworking or processing companies as well as composites with a predominant proportion of wood (more than 50 percent by weight). Used wood are used products made of solid wood, wood-based materials or composites with a predominant proportion of wood (more than 50 percent by weight). While the used wood is clearly understood as waste at the end of its service life, this classification is more difficult for industrial waste wood.

With the reorganization of the Recycling Management Act, saw by-products are clearly no longer waste. The law includes the term “by-products” for the first time in Section 4 of the KrWG.

This is important for the sawmill and wood industry insofar as saw by-products have so far only been defined by interpreting the term "products" and the fact that there is no will to dispose of them and saw by-products are produced specifically according to market specifications. The term “by-products”, which has now been included in the law, leads to a clarification of the term waste in the cases of the combined production common in the sawing and wood industry.

In the justification for the regulation on the disposal of waste wood (AltholzV), the Federal Cabinet had already determined on February 6, 2002, on presentation of the state working group on waste (LAGA), that waste wood is not recorded: “ Residual wood , which is to be classified as a by-product or by-product is, for example, chips from sawmills or small wood from thinning ”. In the explanation, special part, Article 2.1 (to § 1 area of ​​application) is further elaborated: "This particularly includes unpolluted industrial waste wood (for example shavings from sawmills), which in the opinion of the producer or owner, taking into account the public opinion, is a so-called by-product is to be classified (compare § 3 Paragraph 1 Clause 1 in conjunction with Paragraph 3 KrW- / AbfG 1994) not in the scope of the [Waste Wood] Ordinance ”. The same applies to so-called residual forest wood (small wood resulting from thinning).

Reclaimed wood categories

Due to the different origins of waste wood, waste wood can be contaminated with foreign substances to different degrees. For this reason, the wood in § 2 No. 4 AltHolzV is divided into four categories of waste wood:

  • A I - natural wood that has only been mechanically processed,
  • A II - glued, painted, coated, varnished or otherwise treated waste wood without organohalogen compounds in the coating and without wood preservatives,
  • A III - waste wood with organohalogen compounds in the coating without wood preservatives,
  • A IV - waste wood treated with wood preservatives , such as railway sleepers , line masts , hop poles , vine stakes, as well as other waste wood that cannot be assigned to waste wood categories A I to A III due to its pollution, with the exception of PCB waste wood.

In addition, it is classified as waste wood containing PCBs . This is waste wood that contains polychlorinated biphenyls within the meaning of the PCB / PCT waste ordinance and must be disposed of in accordance with their regulations. In particular, these are insulation and soundproofing panels that have been treated with agents that contain polychlorinated biphenyls ( Section 2 No. 5 AltHolzV).

In order to simplify the use of the materials, an attempt is made to keep different waste wood streams separate and thus prevent the different qualities from being mixed up. The quality of the individual wood fractions can also be improved by technical sorting processes, for example by air sifting scrap wood chips to sort out coating residues.

Come up

The majority of the waste wood is collected and disposed of separately. Other waste wood, which were previously deposited in mixed waste will be collected separately since 2005, as the legally become in June 2005 Storage Ordinance prohibits the dumping of untreated waste from households and industries by law. In Germany, around 95 kg of waste wood are produced per inhabitant each year, 65 kg of which are collected separately. This volume results in an annual total of about 8 million tons (2003), of which about 5.4 million tons are collected separately. It is divided into waste from the wood industry (2.441 million tons, completely collected separately), construction waste (3.623 million tons, of which 2.348 million tons collected separately), municipal waste (974,000 tons, of which 385,000 tons collected separately) and packaging waste (891,000 tons, of which 229,000 Tons collected separately).

use

Waste wood can be used for energy as well as material, whereby in Germany currently (2009) energetic use predominates with around two thirds of the volume. Across Europe, around 34% of the waste wood accumulated separately was used energetically and around 38% materially, the remaining 28% was used for other purposes, for example through composting and as mulch stock .

Energetic use

In the energetic use, waste wood is particularly relevant due to the combustion in biomass heating plants or biomass power plants for the generation of electricity and heat. According to the waste wood classification AI wood can be used in all system sizes, while A-II to A-IV wood can only be used in systems with a thermal output of over 1 MW. In the case of A-II wood, incineration in small combustion systems of the wood processing industry is also approved. A-III and A-IV wood combustion require extensive exhaust gas cleaning technologies, which are regulated by the Federal Immission Control Ordinance (17th BImschV) and which, due to the high technical effort, only enable economical combustion from 10 MW thermal output.

Another energetic use is the incineration as secondary fuel in furnaces, which are primarily fired by fossil fuels (co-firing). This plays a role in Germany especially in the cement industry .

Material use

Chipboard is the most important material use for waste wood

Waste wood can be used materially in the wood-based materials industry in particular , whereby only AI and A-II woods can be used without restrictions if untreated. A-III woods can only be used if varnishes and coatings are removed before use. There are very few plants for processing A-III woods (only one in Germany). Waste wood contaminated with A-IV and PCBs is not permitted for further material use.

Reclaimed wood is used primarily in the production of molded pressed wood parts (compressed wood pallets), chipboard and, less frequently, in the production of medium-density fibreboard (MDF), with a total of between 1.7 and 3.0 million tons of waste wood being processed in Germany each year . Waste wood chips are also used in small quantities in niche applications, for example as animal bedding in equestrian halls. In addition to these uses, the Waste Wood Ordinance also provides for the use of waste wood for the production of synthesis gas as a raw material for the chemical industry or the production of activated charcoal or industrial charcoal ( Section 2 No. 7 lit. c AltHolzV).

Scrap wood is occasionally used again as a building material. When renovating half-timbered buildings, it makes sense to use old wood . Reclaimed wood is also occasionally reused in new buildings; here, depending on the client, either aesthetic or ecological aspects provide the impetus. Reclaimed wood is also used to create a rustic look in furniture or interior fittings. The waste wood is either processed in the original form as a beam, plank or board or in the form of multi-layer panels with a top layer of waste wood. On the one hand, waste wood is delivered to joiners and carpenters via the timber wholesalers, but it also finds its way directly to the end consumer via hardware stores.

literature

  • Old wood. In: Martin Kaltschmitt, Hans Hartmann, Hermann Hofbauer (Hrsg.): Energy from biomass. Basics, techniques and procedures. 2nd edition, Springer Verlag, Berlin / Heidelberg 2009; ISBN 978-3-540-85094-6 , doi : 10.1007 / 978-3-540-85095-3 , pp. 143-148.
  • B. Sundermann, F. Spoden, R. Dohr: Emergence and recycling routes for waste wood in Germany. Garbage and waste 31 (5), 1999, ISSN  0027-2957 , p. 269 ff.
  • Udo Mantau , Jörg Wagner, Janett Baumann: Wood material flow model: Determination of the occurrence, use and whereabouts of wood products. Garbage and waste 37 (6), 2005, ISSN  0027-2957 , pp. 309-315.
  • Federal Association of Waste Wood Processors and Recyclers (BAV e.V.) (Ed.): Guide to waste wood recovery

Individual evidence

  1. Kaltschmitt et al., 2009, p. 144.
  2. Kaltschmitt et al., 2009, p. 145.
  3. a b c d Energetic use. In Kaltschmitt et al., 2009, pp. 147-148.
  4. Appendix I (to Section 3, Paragraph 1): Procedure for the recycling of waste wood. In: Ordinance on requirements for the recovery and disposal of waste wood (Altholzverordnung - AltholzV). From Rechts-im-Internet.de, accessed on February 3, 2017.
  5. a b Material use. In Kaltschmitt et al., 2009, p. 147.
  6. Current projects, objects and offers from Thomas Knapp Historische Baustoffe GmbH. Retrieved February 6, 2019 .
  7. Current projects, objects and offers from Thomas Knapp Historische Baustoffe GmbH. Retrieved February 6, 2019 .