The Prediction of Thermal Conductivity of Agricultural Residues from Straw for Biomass Energy

Abstract

Agricultural residues from straw are widely used for energy and other applications. The thermal conductivity is one of the most important thermophysical properties considered when using agricultural residues, such as rice straw, in renewable energy engineering. In this paper, the thermal conductivity of rice straw was measured using a thermal probe by the transient hot wire method at selected moisture contents, temperatures and dry densities. The moisture contents of the samples ranged from 0 to 21.47 percent wet basis and the dry densities ranged from 90.7 to 136.4 kg/m3 and the temperature ranged from 0 to 170°C. Under those conditions, the thermal conductivity was measured and analyzed. Experiment results showed that the thermal conductivity increases with the increases of the density, moisture content and temperature, and the relationship among them is approximately described in a linear way. A new model to predict the thermal conductivity of agricultural residues from straw was proposed. The calculated results by the proposed model are in good agreement with the experimental data.

Simulation Studies on Microwave Assisted Drying of Biomass With Special Attention to the Size of Biomass

“…The simulation requires defining the electrical and thermal properties of rice straw. The same is provided in Table 2 [9][10][11]. The parametric study with the length of the rice stubble is performed for analysis.…”