Characterization of Clay and Granite Dust Blends as Novel Materials for Energy Storage and Diffuser in Constructing Flat-plate Solar Collector

Sun is the main source of solar energy, and the energy it releases to the Earth’s surface in one hour is more than what the whole planet consumes in a year. This present work is about characterizing novel material that can be used as energy storage and diffuser in constructing flat plate solar collector. Materials used are clay and granite dust obtained from Okelele and Kulende Quarry sites, both in Ilorin, Kwara State, Nigeria. The materials were sun-dried; the clay crushed before the two materials were sieved into different particle sizes. They were thereafter blended into different ratios and then characterized for thermal, physical and mechanical properties. Results showed that the highest thermal conductivity, thermal diffusivity and compressive strength were obtained from sample of particle size 0.075 mm and clay: granite ratio 50:50 (0.268176 W/mK, 3.58514 10–4 m2/sec and 3.571 N/m2, respectively). This same blend has a density of 0.91 g/cm3 and specific heat capacity of 824 J/kgK. This sample, having the optimal thermal, physical and mechanical properties will be a good replacement for conventional insulating materials currently being used for solar flat-plate collector construction as it will serve as both energy storage and diffuser. Keywords:    Solar energy; solar collector; insulating material; clay; granite dust; thermal conductivity; thermal diffusivity &nbsp

MODELING AND SIMULATION OF MECHANICAL PROPERTIES OF PULVERIZED COW BONE AND LATERITIC PAVING TILES

This study included the experimental production and investigation of the mechanicalproperties of paving tiles produced from a mixture of laterite, silica sand, pulverized cow bones,and cement. Empirical models of compressive and flexural strength were also developed andherein presented for the paving tiles. The maximum compressive strength of the paving tiles wereobtained for 20, 15, and 10% cement content as 5.05, 5.05 and 3.08 MPa, while the maximumflexural strength for similar values of cement content were obtained as 1.83, 1.21 and 0.26 MParespectively. The results indicate that there was no noticeable difference in the values of thecompressive strength at 20 and 15% cement content, while a sharp reduction of the mechanicalproperties was experienced as the cement content reduces from 15 to 10%. Recommendedcomposition for paving tiles with pulverized cow bones composite is cement, 15%; pulverized cowbones, 30%; laterite 35% and silica sand, 20% respectively. Sustainable production of paving tilesand a sustainable environment can, therefore, be enhanced by replacing granite constituent withwaste cow bones, which can easily be replicated by the empirical models herein developed