Investigation of combustion of lignite and torrefied biomass in a thermogravimetric analyzer (TGA) and in a circulating fluidized bed (CFB) under oxy-fuel combustion conditions

Download

index.pdf

Date

2019

Author

Barzegar, Ramin

Metadata

Show full item record

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

Item Usage Stats

247
views

144
downloads

In this study, the combustion of Turkish lignites (Orhaneli and Soma), torrefied woodchip, and their blends was studied under oxygen-enriched and oxy-fuel combustion conditions in a thermogravimetric analyzer. The iso-conversional kinetic methods were used to estimate the Arrhenius parameters and the uncertainty assessments associated with the kinetic calculations were considered. The co-combustion experiments showed a synergetic effect between the biomass samples and Orhaneli lignite. Based on the obtained results, Orhaneli lignite and the biomass torrefied at 300°C-30 min torrefaction conditions were selected for further analysis in a laboratory scale Circulating Fluidized Bed Combustor (CFBC). The CFBC experiments were conducted under oxygen-enriched and oxy-fuel combustion conditions and included the addition of calcium-based sorbents (Çan limestone and Eskişehir dolomite) for in-situ adsorption of sulfur dioxide emission. The conducted CFBC experiments showed that the sulfur dioxide removal was more effective with the addition of Çan limestone with the particle size of 1-2 mm and Ca/S ratio of 2. Also, increasing the oxygen concentration was an effective solution in sulfur retention. Furthermore, the combustion process in the CFBC was numerically simulated and the results were compared with the experiments. The simulation results showed a good agreement with the experimental data in estimation of the combustor temperature and carbon-based efficiency.

Subject Keywords

Biomass energy., Oxy-fuel Combustion, Co-combustion, Torrefied biomass, CFBC, Sulfur Capture.

URI

http://etd.lib.metu.edu.tr/upload/12623867/index.pdf
https://hdl.handle.net/11511/45087

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Investigation of co-combustion characteristics of low quality lignite coals and biomass with thermogravimetric analysis Varol, Murat; Atımtay, Aysel; Bay, B.; Olgun, H. (2010-10-20) In this study, combustion and co-combustion characteristics of three biomass fuels and three Turkish lignite coals were investigated by using a thermo gravimetric analyzer. There are just a few studies investigating the co-combustion characteristics of coal and biomass, and the synergistic effect of their various combinations on the peak temperatures and burnout times.
Combustion characteristics of Turkish lignites at oxygen-enriched and oxy-fuel combustion conditions Barzegar, Ramin; Yozgatlıgil, Ahmet; Atımtay, Aysel (2019-10-01) Combustion and oxy-fuel combustion characteristics of two Turkish lignites (Orhaneli and Soma) were investigated by Thermogravimetric Analysis (TGA) method. Experiments were carried out under oxygen-enriched air and oxy-fuel combustion conditions with 21, 30, 40% oxygen concentrations. Three heating rates of 5, 10, and 20 degrees C/min were considered and the isoconversional kinetic methods of FWO, KAS, and Friedman were employed to estimate activation energies. The uncertainty assessment in obtaining the a...
Characterization of lignocellulose biomass and model compounds by thermogravimetry Kök, Mustafa Verşan (Informa UK Limited, 2017-01-01) In this research, combustion characteristics of lignocellulose biomass (hazelnut shell) and three main components (cellulose, hemicellulose, and lignin) were investigated using thermogravimetry (TGA-DTG) technique at different heating rates. The ignition, peak, burn-out temperatures, and the heat liberation of lignocellulose biomass and three main components were also measured. Two different model-free kinetic methods, known as Ozawa-Flynn-Wall (OFW) and Kissinger-Akahira-Sunose (KAS), were used in order to...
In-situ combustion laboratory studies of Turkish heavy oil reservoirs Bagci, Suat; Kök, Mustafa Verşan (Elsevier BV, 2001-12) The purpose of this research was to perform dry and wet forward combustion experiments for Turkish heavy oil reservoirs (Raman, Adiyaman and Çamurlu and Bati Kozluca) under different experimental conditions. In the experiments, a vertical tube was packed with crushed limestone and saturated with crude oil and water. It was observed that peak temperatures were higher when stabilized combustion was achieved and decreased as the combustion front approached the outlet end of the tube. In wet combustion experime...
Combustion of Turkish lignites and olive residue: Experiments and kinetic modelling Magalhaes, Duarte; Kazanç Özerinç, Feyza; Riaza, Juan; Erensoy, Sevgi; Kabakli, Ozde; Chalmers, Hannah (2017-09-01) This study investigated the combustion behavior and kinetics of Turkish fuels. Two lignite coals from Tuncbilek and Soma region, and olive residue, were used, all within a size range of 106-125 mm. Experiments were performed in a thermogravimetric analyzer (TGA) coupled with a differential thermal analyzer (DTA), under three different heating rates, namely 15, 20, and 40 degrees C/min. Based on the weight loss (TG) and derivative weight loss (DTG) curves, the characteristic temperatures were determined, thr...

Citation Formats

R. Barzegar, “Investigation of combustion of lignite and torrefied biomass in a thermogravimetric analyzer (TGA) and in a circulating fluidized bed (CFB) under oxy-fuel combustion conditions,” Thesis (Ph.D.) -- Graduate School of Natural and Applied Sciences. Mechanical Engineering., Middle East Technical University, 2019.