Recycling of Rice Husk into a Locally-Made Water-Resistant Particle Board

Abstract

A large quantity of rice husk in Nigerian rice milling industries poses a serious environmental health hazards. Rice husk particleboard is therefore one of such material which may be considered a potential substitutes for woods-based board products. This study presents an experimental work which investigates the potentiality of rice husk in the production of particleboards using starch wood glue (Top bond) as an alternative source of adhesives. The weighing scale was used to weigh the rice husk, starch, wood glue (Top bond) the mixture ratio adopted being 0.75 kg: 0.15 kg: 0.10 kg of the rice husk, starch, wood glue respectively, thoroughly mixed manually by using the mixer. The mixture was then poured into a mould with a dimension 300 mm × 300 mm × 15 mm. The particleboard was compacted using a hydraulic press in two (2) compacts. The particleboard was tested for water absorption in both cold hot media. The cold absorption test was performed by immersing the composite sample was immersed into the cold water a period of 30mins, 1 h, 2 h, 4 h, 6 h 8 h at room temperature (25°C) the thickness of the board. In hot absorption test, the composite sample was immersed into the hot water with temperature ranging 45°C, 65°C, 85°C and 100°C at constant time of period of 1hour the thickness of the board taken. The percentages of absorption were then calculated for both the cold the hot medium. The thickness of the particle board produced increases with an increasing time temperature for both the cold hot media water, until a point is reached when a saturation point is attained the board could no longer accommodate any more water. At this point the density remains constant. This value indicates that the board should be reserved for indoor application since percentage water absorption absorbed increases with increasing time of immersion. It is concluded that rice husk waste can be utilized in the manufacture of a water-resistant particleboard tropical area like Nigeria with long raining season. The use of starch, a biodegradable adhesive reduced the use of the more expensive synthetic adhesive based on petroleum resources. The test results showed that the rice husk, starch wood glue combination provides results which have high potential to be used in the production of particleboard.