CHARACTERIZATION AND THERMAL DECOMPOSITION OF HYBRID COAL

• Main Author: Rizka Lakzita, Pradhipta
• Format: Theses
• Language: Indonesia
• Subjects: Teknik kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/54803
• Institution: Institut Teknologi Bandung

Characterization of hybrid coal is necessary because thermal decomposition characteristics data can be used to determine the optimal combustion conditions to obtain maximum energy conversion. This optimum condition can be used in designing the right reactor to utilize hybrid coal as an energy source. In this research, the thermochemical characterization and intrinsic kinetics of the reaction were carried out to obtain the parameters of the combustion reaction kinetics and to identify the thermal decomposition process that occurred. The experiment carried out was a Thermogravimetric Analyzer (TGA). The samples used for thermal degradation with TGA are four variations of hybrid coal and each of 500 mg from temperatures of 25°C to 1000°C with variations in heating rates of 5°C / minute, 10°C / minute, and 15°C / minute. From the experiment, the mass reduction data were obtained. Determination of kinetic parameters in this study using two methods, namely the free model method (FWO, KAS, and Starink) and the fitting model method (Coats-Redfern). Based on the TG and DTG charts, the Sapuandi and Ikhsan hybrid coals are more reactive than the Suyadi hybrid coals. The free-model method of activation energy value (Ea) between FWO, KAS, and Starink has almost the same correlation coefficient (R2) and Ea. The activation energy values for Lignite-Pine are in the range 90.06-241.29 kJ / mol; Lignite-Rubber in the range of 48.21-152.69 kJ / mol and Subbituminous-Rubber in the range of 36.45-120.57 kJ / mol. According to the fitting-model method, it is influenced by the O and D models, namely chemical reactions and diffusion reactions. Overall controlled by model O, chemical reactions of order 1,2, and 3. Activation energy values for Lignite-Pinus stage 1 in the range 65.48-172.18 kJ / mol and stage 2 in the range 23.94 -118.97 kJ / mol; Lignite-Rubber in the range 43.02-118.60 kJ / mol and Subbituminous- Rubber in the range 34.13-95.76 kJ / mol.