Zur Nutzung von Agrar-Reststoffen in der Holzwerkstoffindustrie

Abstract

Considering on-going global deforestation and the increased demand for raw materials in all wood-processing sectors it is necessary to seek and employ alternative resources. Particularly for the wood-based panel industry (partial) substitution of conventional wood material by agricultural residues, for example, cereal straws or suitable lignocellulose-based raw materials may proof to be a resource of increasing importance. If some economic conditions (transport, storage, pre-treatment costs) are favourable, the use of these residues will satisfy the different aspects of sustainable management. The material utilization of renewable raw materials for high quality products generates high added value for both producers and rural suppliers. Furthermore, negative impacts on the environment (air pollution, high water consumption) due to conventional waste disposal and overexploitation of forests are reduced. An overview of potentials, development and challenges in the field of panel production made from agro-based lignocelluloses is provided

Alternative Materials from Agro-Industry for Wood Panel Manufacturing—A Review

“…The husks of cereals usually have low cellulose content, i.e., the respective cellulose content in corn, oat, and rice husks are 18%, 38.7%, and 25-45%, and vary with the growth conditions. Nevertheless, the ash content is generally higher than wood, which may cause some limitations for their processing by reducing the service life of machinery, i.e., tool wear, cutting or grinding machines [14,71,72]. A high ash content might be advantageous for specific applications.…”

“…Simultaneously, it relieves the pressure on virgin forest raw materials. Although there are various studies on the utilization of NWLMs and ARs for wood-based panels [10][11][12][13] and reviews that collected and summarized the findings [5,[14][15][16], there is still a lack of information about the critical requirements of these materials to serve as a partial or entire replacement of wood.…”

“…Some material properties, such as the anisotropic and hygroscopic characteristics of NWLM and ARs are similar to that of wood, while their density is generally lower [14]. This brings an advantage for producing low-density composites.…”

“…However, since combustion releases greenhouse gases causes high levels of air pollution, the field burning of agricultural waste or residu not permitted in most of the European Union's member states, among other places [ Valorizing the ARs into value-added products, such as in wood panel manufact (mainly particleboards and fiberboards), increases their value and brings ecological ben Simultaneously, it relieves the pressure on virgin forest raw materials. Although there ar ious studies on the utilization of NWLMs and ARs for wood-based panels [10][11][12][13] and rev that collected and summarized the findings [5,[14][15][16], there is still a lack of information a the critical requirements of these materials to serve as a partial or entire replacement of w Some material properties, such as the anisotropic and hygroscopic characterist NWLM and ARs are similar to that of wood, while their density is generally lower [14] brings an advantage for producing low-density composites. The wood particles or fibers not be replaced with alternative materials in a one-to-one ratio due to their low mecha strength and high proportion of fines [17].…”

Anaerobic digestion of monocotyledons in particleboard production – a concept of process integration to increase substitution of wood raw material

“…It is, however, difficult to include alternative raw materials, such as monocotyledons, in the conventional process for the production of particleboards (Müller, Schwarz and Thole 2012). The physical and chemical properties of monocotyledons vary even within a single species and they are essentially different from those of wood (Pahkala and Pihala 2000; Wiśniewska et al 2003).…”