Karakterisasi Pelet Kayu Karet (Hevea brasiliensis) Hasil Torefaksi dengan Menggunakan Reaktor Counter-Flow Multi Baffle (COMB) (Characterization of Rubberwood (Hevea brasiliensis) Pellets Torrefied with Counter-Flow Multi Baffle (COMB) Reactor)

Abstrak

Indonesia has the largest rubberwood (Hevea brasiliensis) plantation area in the world. Rubberwood is mainly planted for latex production and as latex production declines with age, rubberwood is generally felled. The logging waste and industrial waste of rubberwood-based products could be utilized as raw materials to produce biomass pellets. The quality of biomass pellets can be increased through torrefaction, a thermal process in the temperature range of 200-300°C under an inert atmosphere. This study aimed to evaluate the effect of torrefaction on the characteristics of rubberwood pellets. The torrefaction of rubberwood pellets was conducted using the Counter-Flow Multi Baffle (COMB) reactor, a reactor that could perform torrefaction within a short residence time of up to 5 min. The temperature used in this study was 200°C, 250°C, dan 300°C with a residence time of 3 min. The color change, physical properties, chemical composition, and heating value were evaluated. The results showed that the pellet’s color changed from light brown into black pellets, showing the overall color change (∆E*) of 29,12, 54,27, and 66,71, after torrefaction at 200°C, 250°C, and 300°C, respectively. The equilibrium moisture content of the pellets decreased from 12,25% to 3,54%. The water immersion test also showed that the torrefied pellets have a better hydrophobicity, which is an advantage when pellets are stored in a humid condition. The oven-dry density of pellet decreased from 1,15 g/cm3 to 1,09 g/cm3, 1,04 g/cm3, and 0,96 g/cm3, after torrefaction at temperatures of 200°C, 250°C, and 300°C, respectively. Torrefaction caused a decrease of cellulose and hemicellulose contents, an increase of lignin content, and a remarkable increase in the heating value of 1,71-18,32% with increasing torrefaction temperature. The results proposed that torrefaction using the COMB reactor could provide a great improvement in the quality of rubberwood pellets to improve the additional value of the products.Keywords: black pellet, Counter-Flow Multi Baffle, rubberwood (Hevea brasiliensis), torrefaction