Combustion mechanism and model free kinetics of different origin coal samples: Thermal analysis approach

Jayaraman K., KÖK M. V., Gokalp I.

ENERGY, cilt.204, 2020 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 204
  • Basım Tarihi: 2020
  • Doi Numarası: 10.1016/j.energy.2020.117905
  • Dergi Adı: ENERGY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Agricultural & Environmental Science Database, Applied Science & Technology Source, Aquatic Science & Fisheries Abstracts (ASFA), CAB Abstracts, Communication Abstracts, Compendex, Computer & Applied Sciences, Environment Index, Geobase, INSPEC, Metadex, Pollution Abstracts, Public Affairs Index, Veterinary Science Database, Civil Engineering Abstracts
  • Anahtar Kelimeler: Coal, Thermogravimetry, Mass spectrometry, Combustion, Model free kinetics, HIGH ASH COAL, THERMOGRAVIMETRIC ANALYSIS, PULVERIZED COAL, PARTICLE-SIZE, PYROLYSIS, GASIFICATION, COCOMBUSTION, WASTE, BEHAVIOR, BLENDS
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

Five coal samples from different origins are characterized for their pyrolysis and combustion features using coupled thermogravimetry - mass spectrometry (TG-MS). The samples are heated at temperatures ranging from 25 to 900 degrees C in air atmosphere under heating rates of 10, 20, and 30 degrees C/min. The characteristic temperatures (initial, peak, burn out), reaction intervals, mass loss rate, ash residues, ignition and combustion performances, an ignition-combustion index and the reactivities of the coal samples are calculated and the associated heating rate effects are estimated. The less reactive coal exhibits higher peak temperature in conversion and low value of ignition index and reactivity. The reactivity of the coal samples varied in between 2.31 and 7.84 x10(2) (1/min). The main volatile and combustion products (H-2, CH4, H2O, CO, CO2, C6H6, COS, SO2) release for the corresponding TG and temperatures are estimated using online 3D measurements of MS based on their relative intensities and relevancy. Ozawa-Flynn-Wall (OFW) and Kissinger-Akahira-Sunose (KAS) type model free kinetic methods are applied to determine the activation energies of the coals which are exhibited in-between 44.6 - 75.1 kJ/mol and 50.5-96.6 kJ/mol using OFW and KAS methods respectively. The estimated kinetic constants are compared and found consistent with combustion performance parameters. (C) 2020 Elsevier Ltd. All rights reserved.