Heat Transfer Investigation in Natural Fibers Insulation for Steam Pipes Application

The main goal of this study was to investigate the heat transfer in natural insulation made from sisal fiber, banana fiber, sheep wool, and rice husk ash that can be used for steam water pipes. The preparation of Sheep Wool Rice Husk Ash (SWRHA), Sisal Fiber Rice Husk Ash (SFRHA), and Bananas Fiber Rice Husk Ash (BFRHA) and Air gap insulation were done. Heat loss through pipes from asbestos insulation was prevented by comparing SWRHA, SFRHA, and BFRHA with an air gap. Steel pipes had a 63 mm internal diameter and a 1-meter length. The length (1.1 m) and diameter of pipe insulation are the same (172 mm). On the other hand, the pipe thicknesses of BFRHA, SFRHA, SWRHA, and Asbestos insulation had 80 mm, and 106 mm respectively. The maximum thermal conductivity of sisal fiber, sheep wool, banana fiber, and rice husk ash were (0.045, 0.044, 0.094, and 0.4) W/mK respectively. The maximum and minimum heat loss of BFRHA, SFRHA, SWRHA with air gap and asbestos insulation were (225.132, 223.38, 222.33, and 1328.271) kWh/yr, and (41.70, 52.56, 19.71, and 46.428) kWh/yr, respectively. For a unit length pipe at 90°C, the maximum energy saving of BFRHA, SFRHA, SWRHA with air gap and asbestos insulate was (244.708, 242.804, 241.602, and 1443.772) kWh/yr, irrespectively. Therefore, as the result indicated, the performance of BFRHA, SFRHA, and SWRHA with air gap is better than that of asbestos insulation. The result also showed that SWRHA with air gap insulation was better and cost-effective option than other insulating materials.