Document Type : Research Paper

Abstract

Part of the process of feed preparation or oil extraction for date pits is to soak the pits in water. Soaking softens the pits and reduces the required milling energy. In this research, the effects of water temperature at 25°, 35°, 55° and 65°C on water absorption and grinding of the date pits was investigated. The water absorption curves indicated that the rate of absorption and the final moisture content of the pits increased as the water temperature increased. The final moisture content of the pits for these temperatures were 59%, 62%, 71% and 73% w.b., respectively. Modeling water absorption using analytical, Page and exponential models indicated that the three models showed good fit with the experimental data (R2>0.95). The best results were obtained using the Page model with R2 = 0.99. The results of grinding the pits indicted that the average diameter of the ground particles decreased as soaking time and temperature of the water increased. A logarithmic model was defined to express the diameter of the particles as a function of grinding time. The presented model fit well with the experimental data (R2>0.98).

Keywords

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