Papers by Author: J.O. Osarenmwinda

Abstract: Study was carried out to develop a composite material from agro waste consisting of sawdust and palm kernel shell and to determine its physical and mechanical properties. The sawdust / palm kernel shell compositions by weight were in the ratios of 100: 0, 90: 10, 80: 20, 70: 30, 60: 40 and 50:50. Urea formaldehyde was used as the test binder at concentrations of 20% of oven dry weight of agro waste. Particle size of agro waste used was 300µm .Yield strength, ultimate tensile strength, modulus of elasticity, modulus of rupture, internal bond strength, density, thickness swelling and water absorption of the formed composite materials were determined and observed to be enhanced at high palm kernel shell composition. The composite composition by weight that gave the best results out of the six compositions tested was the one with sawdust: palm kernel composition of 50%:50% with its properties as: yield strength ( 4.47 N/mm²) ,ultimate tensile strength (7.75 N/mm²), modulus of elasticity (2603 N/mm²), modulus of rupture (16.67 N/mm² ), internal bond strength ( 0.54 N/mm² ), thickness swelling (10.30%) ,water absorption (18.90%) and density (996.18kg/m³).

Abstract: The production of an improved sawdust briquette, as an alternate source of fuel has been achieved. In addition to sawdust other constituents of the briquette were silica (sharp sand), starch and kerosene. The density, ash content, calorific values and moisture content of briquette were determined. The composition of starch and kerosene was constant throughout the experiment. It was observed that as silica percentage was increased, there was an increase in the briquette calorific value until maximum value of 20%. The sample which gave the best calorific value was with percentage compositions of 60% sawdust, 20% silica (sharp sand), 5% kerosene and 15% starch with a calorific value of 12.68mJ/kg .The produced briquette had a higher calorific value than wood and other agro waste it was compared with.

Abstract: The potential of periwinkle shell as coarse aggregate for concrete was studied in this paper. The properties of concrete made with periwinkle shell as coarse aggregate were examined. Test conducted on the concrete was compressive strength test. Prescribed mix designs of 1:1:2, 1:2:3, 1:4:6, 1:2:4 and 1:3:5 were used to produce concrete cubes used for testing. The different constituents that make up the periwinkle concrete are presented in ratio form as cement: sharp Sand: Periwinkle shell. Batching was done by volume and the corresponding weight recorded. The cubes were made and tested at hydration periods of 7, 14, 21 and 28 days to determine the compressive strength of the periwinkle shell concrete. The results show that periwinkle shell has a bulk density of 517kg/m3 and specific gravity of 2.05. The results also shows that design mix of 1:1:2, 1:2:3 and 1:2:4 with compressive strength of 25.67 N/mm2, 19.50N/mm2 and 19.83N/mm2 at 28 days hydration period respectively met the ASTM-77 recommended minimum strength of 17N/mm2 for structural light weight concrete while mix design of 1:4:6, and 1:3:5 with compressive strength of 14.00N/mm2 and 16.50N/mm2 respectively did not met the standard.

Abstract: The purpose of this study was to determine the effect of particle size on the mechanical properties (Modulus of Elasticity, Modulus of Rupture, and Internal Bond) and physical properties (thickness swelling and water absorption) of rice husk particleboard. The particle sizes used were 1.0mm, 1.18mm, 2mm, 2.36mm and 2.80mm. Each was mixed with a constant resin (urea formaldehyde) concentration of 20% of oven dry weight of rice husk particles. The results showed that as the particle size increased, the particleboard’s mechanical and physical properties decreased. For example, the modulus of elasticity, modulus of rupture, internal bond, thickness swelling and water absorption for 1.0mm particle size particleboard were 1590N/mm2, 11.11N/mm2, 0.28N/mm2,10.90% and 38.53% respectively, while for 2.8mm particle size they were 1958N/mm2,14.2N/mm2, 0.44N/mm2, 11.51% and 47.21% respectively. Overall results showed that particleboard made from rice husk exceed the EN standard for modulus of elasticity, modulus of rupture, internal bond. However, thickness swelling values were poor. Hence, the smaller the particle size the better the properties of the particleboard.