„BESTPELLET“ - Increase the efficiency of production of pellets with using additives
Summary of obtained results
Control system of production line was adapted, filled and tuned up for application of adding- additive technology. Adjustments of production line and pellets mill were realized and they allowed steady supply of material to matrix (die) with equidistant presence of required additives. Adding system of hot water was installed in two steps that allowed easier integration of additives to input material. It was designed experimental pellets mill and experimental device of adding additives. Mechanical and energetic properties of wood pellets with additives produced by experimental and practice production were studied. Experimental measurements of energetic and environmental aspect of combustion with laboratory and practically produced wood pellets (with additives) were made in production units CPU located in Kysucky Lieskovec. It was published specialist publications (scientific articles) and was realized other promotion activities (trainings, courses, seminars, atc...). The conference focused on results of APPV project was organized by BIOMASA with support of APVV agency. Scientific book publications "Wood pellets and additives" was issued by research team of project. The obtained results were analyzed in detail. The most suitable additives with appropriate percentage in wood pellets - 0.5 % dolomite and 0.3 % wheat starch were applied to practical production in production units of BIOMASA. The obtained results show, that additives are very interesting medium. Adding of additives to wood sawdust of lower quality effect to the properties of wood pellets. Both types of additives (wheat starch and dolomite) improve markedly abrasion and powder density of produced wood pellets. The effect of additives on production cost is most significant in case of wheat starch, which decreases significantly production cost (decreases electricity consumption and input power of pellet mill). Pellets with dolomite (0.5%) have higher flow temperature. It can lead to reduction of slagging and fouling especially in low power boilers.
Additions of additives to wood pellets affect emission values, performance and efficiency of boiler. Optimal results are recorded in dolomite (0.5%) and wheat starch (0.3%). Pellets containing 0.5% of dolomite have PM concentration 40 mg.m-3, CO concentration cca 350mg.m-3, boiler performance 18,5 kW and boiler efficiency 87.9%. Pellets containing 0.3% of wheat starch have PM concentration 32 mg.m-3, CO concentration cca 550mg.m-3, boiler performance 18.9 kW and boiler efficiency 87.8%.
Obtained results show, that the most appropriate additive for practice production of wood pellets is dolomite (0.5%) that decreases abrasion, do not increases production cost significantly, and increases of flow temperature.
Additives (dolomite 0.5%, wheat starch 0.3%) improve qualitative and burning properties of wood pellets markedly, but they have a low impact to performance, effectivity and emission parameters of heating devices.The results of project have a big potential to be applied in practical production of pelletizing units.
Obtained results in detail