20.500.12556/RUL-394 Tehnološke značilnosti izdelave lesnih kuriv diplomsko delo - visokošolski strokovni študij Technological characteristics of wood fuel production graduation thesis - higher professional studies Nastajajoča energetska kriza odpira možnosti alternativnim energetskim virom, istočasno pa pridobivajo na pomenu klasična lesna kuriva, oplemenitena z novimi tehnologijami izdelave. S stiskanjem lesne mase lahko zagotovimo višje kurilne vrednosti kuriv, lažji transport in skladiščenje. Postopki izdelave stiskancev so odvisni od končnega proizvoda v obliki sekancev, peletov ali briketov. Na energijsko učinkovitost vplivajo predvsem kakovost lesne mase in njena vlažnost, na uporabnost stiskancev pa tudi pogoji med izdelavo. Vplive vlažnosti in temperature med stiskanjem smo raziskali z laboratorijskimi poskusi. Izdelana je bila posebna stiskalna naprava za izdelavo stiskancev, ki smo jo vstavili v testirni stroj Zwick. Bukovo žagovino smo uravnovesili na vlažnosti 9,8 %, 11,8 %, 14,8 %, 18 % in 27,4 %. Stiskance smo izdelovali pri temperaturah 50°C, 60 °C, 70°C in 80 °C. Po fazi stiskanja, ki je trajala okoli 72 s, smo opazovali sproščanje notranjih napetosti v stiskancih oziroma relaksacijo stiskancev. Rezultate meritev smo normalizirali s pomočjo modelov za stiskanje in sproščanje. Poskusi so pokazali, da smo dobili največje kompaktnosti stiskancev pri vlažnostih pod 15 % in temperaturah nad 50 °C. The emerging energetic crisis paves paths for alternative energy sources and also reverts to classical wood fuels augmented by new production technologies. By compressing wood residues, comparably higher combustion heat values, facilitated transportation and warehousing are obtained. Technological processes are different, depending on the final products being either woodchips, pellets, or briquettes. Their energy efficiency is influenced by the quality of densified wood logs (slugs) and the moisture contents, while their applicability features depend on the conditions during apiston-and-mould process. We tested the moisture and temperature dependencies in several laboratory experiments. A mould was constructed and used in a Zwick testing machine. We balanced beech wood saw residues at 9.8 %,11.8 %, 14.8 %, 18 %, and 27.4 % moisture levels and, afterwards, compressed them at temperatures 50 °C, 60 °C, 70 °C, and 80 °C. After the compression completed in about 72 s, we observed intrinsic tensions in the logs during the relaxation phase. We normalised the resulting measurements by the compression and relaxation models. The experiments proved the best quality densified logs with highest compactness were obtained with moistures below 15 % and temperatures above 50 °C. lesna kuriva bukovina vlažnost temperatura stiskanja wood fuels beech wood moisture compression temperature true false false [D. Kaker] Slovenski jezik Angleški jezik Diplomsko delo 2014-07-11 12:25:24 2014-07-11 12:25:24 2022-07-11 10:22:40 0000-00-00 00:00:00 2009 0 Ljubljana 0 XI, 57 f., [19] f. pril. 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 630*839.81 1745033 vs_kaker_dejan.pdf vs_kaker_dejan.pdf 1 C4A6713C4CA3EBA11D399C474C72F67A b4338e8beda59603651bfd831b0079600284821de7782dbcf5517ba9b8eeb291 5e822e4d-a1b9-11eb-a523-00155dcfd717 20.500.12556/rul/58b1c012-6fa2-4aa5-9d46-01ac2b112cf1 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=132326 Biotehniška fakulteta 0 0 0