Waste wood is assigned to category A III if the wood shows halogen-organic compounds in the coating. However, wood preservatives must not be contained here either.
Halogen-organic compounds are often found on furniture and kitchen parts in the waste wood sector. Elastic decorative films and edgebandings are relevant PVC sources that qualify interior furnishings for the A III category. PVC can also penetrate into the waste wood through plastics from the construction sector, e.g. through plastic fittings on the wood.
The material recycling of A III wood is possible, provided that coatings and varnishes are largely removed by pre-treatment. State-of-the-art treatment technology, such as light goods separators, screening systems or the WKI procedure, separate the loosened surface particles and PVC coatings from the rest of the material.
In thermal utilization, waste wood of category A II is used in large-scale plants. Since combustion requires extensive flue gas cleaning technologies in accordance with the Federal Immission Control Ordinance, use only becomes economical in biomass CHP plants with a thermal firing capacity of more than 10 MW.