Wood production, wood technology, and biotechnological impacts

The Removal of Cured Urea-Formaldehyde Adhesive towards Sustainable Medium Density Fiberboard Production: A Review

“…MDF can be used roughly for 30 years in decorative and interior applications before disposal (Deak 2013). With nearly 10 million m 3 of MDF is produced every year globally, it can be estimated that around 20 million tons will become waste MDF in the next 30 years (FAO 2019;Kharazipour and Kues 2007;Morris 2017). These wastes are regularly disposed in landfills or burned (Morris 2017;Rivela et al 2007).…”

“…Furthermore, disposal of these wastes may be a source of formaldehyde emission due to the degradation of urea-formaldehyde (UF) resins by microorganisms (Pérez 2016). Moreover, the leached UF resins may influence the groundwater and form methane that has a hazardous greenhouse effect than carbon dioxide (Kharazipour and Kues 2007). On the other hand, burning or incineration does not give a solution as it releases dioxins and carbon dioxide (Morris 2017).…”

“…This means to all wood waste, including decorative and interior appliances made from MDF. Therefore, deploying in landfills is not considered as a suitable solution for their handling because the degraded UF resins may affect the subsoil water (Table 2) (Kharazipour and Kues 2007;Rivela et al 2007). In addition, around 72% of the waste produced from MDF manufacturing goes to incineration for energy recovery and 28% goes to landfills (Rivela et al 2007).…”

“…Furthermore, a method to recover the recycled fibers is needed to re-manufacture a new panel from the recycled fibers (Antov et al 2020). Recently, four options are for the recovery of recycled fibers from MDF: ohmic heating process (Moezzipour et al 2018), autoclaving process (Kharazipour and Kues 2007), microrelease and microwave technology (Elias and Bartlett 2018), and hydrothermal process (Lykidis and Grigoriou 2008). Much effort has been done to find ways for recycling waste MDF.…”

“…Another process that can be used to obtain recycled fibers from waste MDF is autoclaving (Kharazipour and Kues 2007). This process combines a vacuum and pressurized steam with mechanical agitation at temperatures of up to 160°C.…”