Influence of Selected Material and Process Parameters on the Durability of Briquettes Made of Shredded Logging Residues

Abstract

The nonhomogeneous physical properties of the raw material in the form of shredded logging residues, and its composition may cause a serious problem in its further use. As a result of conducted research, it was found that the elemental composition of logging residues (low nitrogen and ash contents) is suitable for raw materials dedicated to energy use. The possibility of using this raw material for the production of briquettes and the correlation between the physical properties of the final product and the parameters of the raw material and the briquetting process were also determined. The material used for tests was wood chips with moisture contents of 10%, 15%, 20%, compacted in a closed chamber at the temperatures of 22, 73 and 103 °C at unit pressures of approx. 65 MPa. The best results were obtained for the material moisture content of 10%. It was found that the temperature of the wood chips during agglomeration influences the degree of compaction and durability of the obtained briquettes. It is more advantageous to conduct compaction at a higher temperature. The research also determined the effect of the fractional composition of the briquetted mixture divided into size groups 0–1, 1–4, 4–8, and 8–16 mm, its moisture and temperature of the process on the durability of the product. On the basis of the obtained results, the most favorable fractional composition of the briquetted mixture, its moisture and temperature of the compaction process were determined.