Investigation the Quality of Recycled Medium Density Fiber boards (MDF) via Two Different Method i.e. Hydrothermal and Ohmic heating

Document Type : Research Paper

Authors

1 Ph.D. Student of wood industry, Department of wood and paper science and technology, Faculty of natural resources, University of Tehran, Karaj, Iran

2 Associate Prof., Department of wood and paper science and technology, Faculty of natural resources, University of Tehran, Karaj, Iran

3 Professor, Department of wood and paper science and technology, Faculty of natural resources, University of Tehran, Karaj, Iran

4 Professor, Department of chemical and petroleum engineering, Sharif university of technology,Tehran, Iran

Abstract

In this study, fibers recycled via two different methods; hydrothermal and ohmic heating were used to manufacture medium density fiberboard (MDF). The purpose of this study was to determine the effect of recycling method on practical properties (bending strength, modulus of elasticity, internal bonding and screw holding in edge and surface and thickness swelling after 24 hours water immersion) of the boards. Also, a morphological analysis was done to evaluate the influence of recycling process on fiber dimensions. Also the existence of UF residues were observed by SEM.
The results related to classification and dimension analyze of fibers confirmed the negative influence of recycling process on quality of fibers. Also degree of deterioration in hydrothermal recycling was higher than that of ohmic recycling due to sever condition of heating.
Furthermore, the results showed that recycling of MDF wastes via ohmic heating method resulted in better physical and mechanical propertied as compared to the hydrothermal method. Overall results showed that MDF panels made from recycled fibers via ohmic heating method exceed the minimum values required by EN standards (EN 622-5, 2006) for all properties except thickness swelling. About ohmic heating method, increasing the time of ohmic heating led to improving the practical properties of recycled MDF boards. It was observed by SEM that much more residues of cured UF resin adhesive were existed on the surface of recycled fibers via hydrothermal method. According to the results it can be said that ohmic heating method is a useful process for recycling the wastes of MDF.

Keywords

References

[1] Athanassiadou, E., Roffael, E. and Mantanis,G., 2005. Medium Density Fibreboards (MDF) from Recycled Fibres. Bioresources Journal, 22:1-9.
[2] Moradikia, S., Doosthoseini,K . and Jahan Latibari,A., 2005. Investigation on possibility of utilization of MDF residues in its manufacturing process. Journal of the Iranian Natural Resources, 61(2)453-463. (In Persian).
[3] Dix, B., Schafer, M. and Roffael, E., 2001. Using fibers from waste fiberboards pulped by a thermo-chemical process to produce medium density fiberboard (MDF). Holz als Roh und Werkstoff, 59(4):276-276.
[4] Mantanis , G., Athanassiadou, E., Nakos, P. and Coutinho, A., 2004. A new recycling process for waste panels. In processing of European Countries Conference about Management of recovered wood. 22-24 April, Thessaloniki, Greece:  p 204-210.
[5] Lykidis, C.H. and Grigoriou, A., 2008. Hydrothermal recycling of waste and performance of recycled wooden particleboard. Waste management Journal, 28: 57-63.
[6] Roffael,E., Dix,B., Behn,C. and Bar, G., 2009. Chemical properties of TMP and CTMP prepared from pine wood and UF-bonded medium density fibreboards (MDF). European Journal of wood products, 67:113-115.
[7] Nicewics, D. and Leszek, D., 2010. Recycling of insulation boards by reuse. Journal of Forestry and Wood Technology, 72: 57-61.
[8] Zandi, M. and Niakousari, M., 2012. An investigation in to corrosion and ions migration from electrodes into food in an ohmic heating system. Journal of Wood Science and Technology, 36(9): 47-54. (In Persian).
[9] Bartlett, C. and New, J., 2012. Electrical heating for recycling of MDF. Wood Research Journal, 22 (5): 12-18.
 [10] Roffael, E. and Huster,H.G., 2012. Complex chemical interactions on thermo hydrolytic degradation of urea formaldehyde resins (UF – resins) in recycling UF – bonded boards. European Journal of wood products, 70 : 401-405.
[11] Michanickl, A. and Boehme, C., 2003. Method for recovering chips and fibers of bonded wood materials involves passing of steam through a vessel with such materials which have been soaked with a heated impregnation solution.Patent , DE10144793, WO03026859.
Iranian Journal of Wood and Paper Industries
Volume 8, Issue 2
September 2017
Pages 323-333

Files

Share

How to cite

Statistics