2ABSTRACTRice husk ash is used as a siliceous material to produce a composite panel with acoustic thermal insulation properties.The rice husk ash has about 90% of silica content.Sound absorption coefficient = 0.79 (at 2 KHz)Coefficient of thermal conductivity = Wm-1K-1
3Introduction Rice husk can be utilised as a source of renewable energy.Calorific value = 15MJ/kgMicronised RHA contained high silica.This study explored the use of RHA to produce a lightweight sodium silicate thermal insulation composite material.
4MATERIAL FORMULATION AND PROCESS RHA is used as a siliceous material.The mixture of RHA and sodium silicate solutionplaced in a 50 mm cube mould at a predetermined depthsubjected to elevated temperature in a furnace
5EXPERIMENTALStudy on experimental production of the insulating composite and the determination of :densitycompressive strengththermal conductivitySound absorption coefficient
6EXPERIMENTAL Sodium silicate composite The RHA was mixed with sodium silicate solution in a ratio of 1:3 by weight.filled into a cube mould at about one-third of its depthfurnace at 350C for 3 hours.
7EXPERIMENTAL Lees’ disc method suitable for measuring the thermal conductivity of poor conductors.constructed from three aluminium discs.The heating element was sandwiched between the first and second disc and the test specimen was placed between the second and third disc.The discs and test specimen were clamped together firmly with the heating element and were then placed on the stand.
8RESULTS AND DISCUSSION The micronised RHAspecific gravity of 2.21moisture content of 1.28%specific surface of m2/kg.bulk density of RHA is approximately498 kg/m3.
9RESULTS AND DISCUSSION RHA compositeDensity = 400 to 450 kg/m3.Compressive strength = 1.65 to 1.85 MPa.The composite was found to have a coefficient of thermal conductivity ranging from to Wm-1K-1.
10RESULTS AND DISCUSSION The low compressive strength is unsuitable for use on its own.The inclusion of expanded polystyrene and polyurethane will be experimented to enhance its strength and insulation properties.The effect of spray applied coating on its surface hardness and the acoustic thermal insulation properties will also be studied.
11CONCLUSION Sodium silicate 90% SiO2 RHA Composite density ranging from 400 to 450 kg/m3.compression strength was between 1.65 to 1.85 Mpa.coefficient of thermal conductivity = Wm-1K-1low compressive strength makes it more suitable for use as an acoustic thermal insulation composite material.