Sustainable Particleboards Based on Brewers Spent Grains

L. ROSSI; L. WECHSLER; PELTZER M.A.; CIANNAMEA, E.M.; RUSECKAITE R.A. ; P. M. STEFANI

Polymers

Multidisciplinary Digital Publishing Institute (MDPI)

Año: 2023 vol. 16 p. 1 - 14

Brewer’s spent grain (BSG) is the main solid waste generated in beer production andprimarily consists of barley malt husks. Based on the active promotion of circular economy practicesaimed at recycling food industry by-products, this study assessed for the first time the productionof particleboards based on BSG as the sole source of lignocellulosic material and natural adhesivewithout the use of additives or other substrates. In order to achieve particleboards from entirelysustainable sources, BSG particles have to self-bind by thermo-compression with water. In thiscontext, the aim of this study is to assess the effects of pressing temperatures and particle size onproperties such as modulus of elasticity, modulus of rupture, internal bond, thickness swelling, andwater absorption. The performance of binderless boards was compared with that of a control panel(control) using BSG combined with phenolic resin. Processing conditions were selected to produceboards with a target density of 1000 kg/m³ and a thickness of 5 mm. To confirm the efficiency of the self-adhesion process, scanning electron microscopy was used to examine the boards. The processes of self-adhesion and particle-to-particle contact were facilitated at a pressing temperature of 170 ◦C and a particle size range of 200–2380 μm (ground BSG), resulting in improved flexural properties and enhanced water resistance. The properties of BSG-based binderless boards were comparable to those reported for other biomass residues, suggesting that they might be used in non-structural applications, such as interior decoration.