Gasification profiles of Thrace region coal under CO2, N-2/CO2, and N-2/DRY air environments

Date

2019-04-01

Author

Kök, Mustafa Verşan

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

176
views

0
downloads

( )This research aimed at understanding the gasification behaviour of Thrace-Saray region coal by conducting several thermogravimetry analysis (TGA) experiments. The effects of heating rate (20-50 degrees C/min), final gasification temperature (750-950 degrees C), and isothermal gasification duration (60-120 min) on the overall gasification processes of as received and washed and dried coal samples were determined under CO2,N-2/CO2, and N-2/dry air environments. Three main reaction regions were observed in CO2 and N-2/CO2 gasification experiments. Regions were correlated with the moisture loss and initiation of devolatilization of labile volatiles (50-200 degrees C), the main pyrolysis stage (200-600 degrees C), at which the comparatively stronger bonds break and devolatilization of heavier volatiles with char evolution occur, and the final gasification stage ( > 800 degrees C) respectively. Obtained thermogravimetry and differential thermogravimetry (TG/DTG) curves were further interpreted based on reaction initiation temperature, peak temperature, maximum mass loss rate, and residue percentage. Based on the evaluated parameters, higher gasification temperature (950 degrees C), longer isothermal duration (120min.), lower gas flow rate (60 ml/min), and the lower heating rate (20 degrees C/min.) for the CO2 gasification process and-comparatively higher heating rate (40 degrees C/min.) for the N-2/CO2 gasification process were found to be the optimum conditions for both of the specified coal samples. The observation of fourth reaction region in N-2/dry air experiments increased the complexity of the analysis and the distinction between the combustion and the gasification reactions. In all experiments, gasification reactivity of the washed and dried coal sample was found to be higher than that of as received coal sample.

Subject Keywords

Isothermal coal gasification, Thermogravimetry analysis, TG/DTG curve

URI

https://hdl.handle.net/11511/41151

Journal

JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING

DOI

https://doi.org/10.1016/j.petrol.2018.12.050

Collections

Department of Petroleum and Natural Gas Engineering, Article

Suggestions

OpenMETU
Core

Coal pyrolysis: Thermogravimetric study and kinetic analysis Kök, Mustafa Verşan (2003-10-01) This research comprises the coal pyrolysis by thermogravimetry (TG/DTG). During the pyrolysis of the coal samples studied, gradual and continuous weight loss over the entire temperature range was observed. The weight loss below 210degreesC is related to the removal of moisture. The subsequent pyrolysis process as revealed by the corresponding DTG peak that is related to primary devolatilization, during which carbon, hydrogen, and oxygen compounds are released. Arrhenius-type kinetic model was used to determ...
Thermal characterization and gasification kinetics of thrace-saray region coal Yıldırım, Betül; Kök, Mustafa Verşan; Department of Petroleum and Natural Gas Engineering (2015) In this thesis being up as-received and washed and dried, two different coal samples from Saray-Edirkoy field were experimented in order to determine effects of different variables as coal type, heating rate, gas flow rate, isothermal duration, gasifying medium, and final gasification temperature, on isothermal gasification profiles of the coal samples. In the scope of this study, heating rate was changed in the range of 20-50oC/min as 20, 30, 40 and 50oC/min whereas two different gas flow rate values as 60...
Thermal investigation of Seyitomer oil shale Kök, Mustafa Verşan (2001-03-22) This research presents the results of experimental study on the thermal investigation of Seyitomer oil shale sample. Thermogravimetry (TG/DTG) and differential scanning calorimetry (DSC) were used to determine the thermal behaviour of the oil shale sample. From the experiments and kinetic analysis, it was observed that Seyitomer oil shale sample have more than one reaction region where the activation energies of the first region are higher. Higher heating rates resulted in higher reaction temperatures both ...
Effect of particle size on coal pyrolysis Kök, Mustafa Verşan; Karacan, Ozgen; Hicyilmaz, Cahit (1998-01-01) This research comprises the effect of particle size on coal pyrolysis by thermogravimetry (TG/DTG). All the experiments were conducted at non-isothermal heating conditions with a heating rate of 10 degrees C min(-1). in the temperature range of 20-600 degrees C, under nitrogen atmosphere. Different fractions of Cayirhan coal coal showed differences in TG/DTG curves, peak temperatures and residue values. The Arrhenius model is applied to determine the kinetic parameters from TG/DTG curves.
Comparative kinetic analysis of raw and cleaned coals Ozbas, K.E.; Kök, Mustafa Verşan; Hicyilmaz, C. (2002-09-24) In this research, thermogravimetry (TG/DTG) was used to determine the kinetic analysis of different coals and effect of cleaning process on kinetic parameters of raw and cleaned coal samples from Soma, Tuncbilek and Afsin Elbistan regions. Kinetic parameters of the samples were determined using Arrhenius and Coats and Redfern kinetic models and the results are discussed.

Citation Formats

M. V. Kök, “Gasification profiles of Thrace region coal under CO2, N-2/CO2, and N-2/DRY air environments,” JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING, pp. 237–245, 2019, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/41151.