Drvna Industrija (Sep 2010)
MDF/HDF Production from Plantation Wood Species
Abstract
The purpose of this research was to establish the raw material base for the newly built MDF/HDF production line in Mohács, Hungary. The desired raw material for the factory is 80 % poplar and 20 % other species (conifers and broad leaved species). These raw materials should be obtained from wood plantations. Laboratory experiments were done in production of MDF and HDF boards with the following raw materials: 5 and 10 year old Pannonia poplar (Populus x euramericana Pannónia), I214 poplar (Populus x euramericana ‘I214’), black locust (Robinia pseudoacacia) and Austrian pine (Pinus nigra). The selected trees were evaluated based on the following parameters: diameter, bark volume, ability for barking, ability for chipping, fiber yield, fiber quality, energy consumption of defibrating, chemical analysis of waste water after defibrating. MDF and HDF boards were made in laboratory from clear poplar species, and from a mixture of poplar and Austrian pine and poplar and black locust. In both cases of mixing, the ratio of poplar and other wood species was 80:20. Ureaformaldehyde adhesive and ammonium-sulphate hardener were used during board production. Also some paraffin was added to increase the moisture resistance. The following board characteristics were tested: bending strength, internal bond, modulus of elasticity, thickness swelling, density, moisture content, formaldehyde content. Except the values of internal bond, the results were very satisfactory, highly above the standard requirements. The reason for the low internal bond values is as follows: - in the laboratory we could not apply a proper blending of fibers and additives, - mat forming by hand. In spite of this, we are sure that an actual technological test production will give good results.
