In the production of pellets made of wood, often wet saw dust is used as entrance material. For pellet production this saw dust must be dried, often drum driers used for drying, using exhaust gases as a heating media. At temperatures above 250 °C some problems in pellet production appear. We assume that higher temperatures influence the chemical structure of material, mostly of lignin. We examined lignin content in saw dust that was dried by exhaust gases at temperatures 200 °C, 230 °C, 375 °C, 400 °C, 420 °C and 440 °C. We were using two methods do establish the difference in lignin content, delignification and lignin content method by Klason. Analysis performed did not present a connection between lignin content and higher temperature used for drying of the entrance material with exhaust gases. We establish that aditional analysis and studies would be necessary to have an answer which componenet and in which extent is changed at higher temperature to result as a decrease of adhesive properties of the pellet material.
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