TY - JOUR TI - INVESTIGATION OF GASEOUS PRODUCT RELEASE PROCESS DURING PYROLYSIS OF COALS OF DIFFERENT CARBONIFICATION DEGREE JN - Thermal Science PY - 1999 VL - 3 IS - 1 SP - 0 EP - 0 PT - Article AB - Vesna B. BARIŠIĆ - M. Sc. Thesis, Faculty of Chemistry, University of Belgrade, Yugoslavia, December 1999, Supervisor: Prof. Dr. Branimir Jovančićević In this thesis the effect of coal carbonification degree, heating rate and particle size on the quantity and quality of coal pyrolysis products was investigated. The pyrolysis process was investigated by thermogravimerty, mass spectrometry and fluidized bed experiments. Five coals from Yugoslavia: two lignite (Kolubara and Kostolac), two subbituminous coals (Soko and Bogovina) and bituminouse coal (Ibar) were used in experiments. The objective of thermogravimetric experiments was to determine the effects of heating rate and coal type on the kinetics of pyrolysis process. Thermogravimetric analyses of coal pyrolysis were performed under an inert nitrogen atmosphere (coal particle size: 0,30-1,00 mm), in the temperature range 30-900 °C at constant heating rates of 20, 40, 80 and 160 °C/min. The weight losses as a function of temperature were recorded (TG-curve) and differential thermogravimetric curves (DTG-curve) were calculated from TG-curves. It was found that total volatile yield, maximal rate temperature and Starting temperature of pyrolysis depends not only on carbonification degree, yet on applied heating rate. The heating rate has different influence on the behavior of coals of different carbonification degree.