A study on the effects of catalysts on pyrolysis and combustion characteristics of Turkish lignite in oxy-fuel conditions

Date

2014-01-01

Author

ABBASI-ATIBEH, Ehsan
Yozgatlıgil, Ahmet

Metadata

Show full item record

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

Item Usage Stats

301
views

0
downloads

The catalytic pyrolysis and combustion characteristics of low calorific value Turkish lignite in various ambient conditions were explored and the evolution of gases during pyrolysis tests was examined using a Thermogravimetric Analyzer coupled with a Fourier Transform Infrared spectrometer (TGA-FTIR). Potassium carbonate (K2CO3), calcium hydroxide (Ca(OH)(2)) and iron (III) oxide (Fe2O3) were employed as precursors of the catalysts and compared to the Raw-form (no catalyst added) to investigate the effects of potassium (K), calcium (Ca) and iron (Fe) on pyrolysis and combustion. Pyrolysis tests were carried out in 100% N-2 and 100% CO2 ambient conditions which are the main diluting gases in air and oxy-fuel combustion. These experiments revealed that the major difference between pyrolysis in these two ambient conditions was observed above 720 degrees C and DTG (Derivative Thermogravimetric) profiles experienced sharp peaks at 785 degrees C in 100% CO2 which can be attributed to a char-CO2 gasification reaction. Furthermore, K2CO3 was found to be the most effective catalyst in the char gasification reaction during pyrolysis tests in 100% CO2. Combustion experiments were carried out in various oxygen concentrations from 21% to 35% O-2 in N-2 and CO2 ambient conditions. Combustion tests carried out in O-2/CO2 ambient conditions revealed that for 30% and 35% O-2, the relative active sequence of catalysts to the reaction rates of devolatilization can be described as Fe >> K > Ca > Raw-form, and Fe > Ca > Raw-form >> K respectively. Furthermore, potassium catalyst had the best char reactivity due to its much higher reaction rates for all oxygen concentrations. The burnout temperature (T-b) also experienced a significant drop in the case of the K-based catalyst. Finally, emission profiles of the evolved gases, CO2, CO, H2O, SOx and COS, were analyzed during pyrolysis tests in both N-2 and CO2 ambient conditions using the FTIR method.

Subject Keywords

Fuel Technology, Organic Chemistry, Energy Engineering and Power Technology, General Chemical Engineering

URI

https://hdl.handle.net/11511/46777

Journal

FUEL

DOI

https://doi.org/10.1016/j.fuel.2013.01.073

Collections

Department of Mechanical Engineering, Article

Suggestions

OpenMETU
Core

A study on the reactivity of various chars from Turkish fuels obtained at high heating rates Magalhaes, Duarte; Riaza, Juan; Kazanç Özerinç, Feyza (Elsevier BV, 2019-03-01) This work investigates the reactivity of chars produced from Turkish biomass and lignite fuels using a wire mesh reactor at high temperature and high heating rate. The fuels studied were olive residue, almond shell, and Soma lignite. Blends of Soma lignite-olive residue and Soma lignite-almond shell were prepared in proportions of 75:25 and 50:50 wt%, respectively. A wire mesh reactor is used for the pyrolysis of the samples in a controlled inert atmosphere at a uniform temperature of 1600 degrees C and at ...
Comparison of single particle combustion behaviours of raw and torrefied biomass with Turkish lignites Magalhaes, Duarte; Panahi, Aidin; Kazanç Özerinç, Feyza; Levendis, Yiannis A. (Elsevier BV, 2019-04-01) This study investigated the combustion behaviour of single pulverized biomass and lignite coal particles under high temperature-high heating rate conditions. Selected fuels included three important agricultural residues in Turkey (olive residue, almond shell, and hazelnut shell), and two lignite coals from the regions of Tuncbilek and Soma in Turkey. Biomass fuels were either raw or torrefied at 275 degrees C for 30 min in nitrogen. The biomass fuels were sieved to a size cut of 212-300 mu m, and the coals ...
Characterization and kinetics of light crude oil combustion in the presence of metallic salts Kök, Mustafa Verşan (American Chemical Society (ACS), 2004-05-01) In this research, a reaction cell, thermogravimetry (TG), and differential thermal analysis (DTA) were used to characterize the light crude oil combustion and kinetics in the presence of copper(I) chloride (CuCl) and magnesium chloride (MgCl2·6H2O). In TG-DTA experiments with magnesium chloride, three reaction regions were identified, known as distillation, low-temperature oxidation (LTO), and high-temperature oxidation (HTO). In the case of copper(I) chloride, two main transitional stages are observed with...
An experimental study on the hypergolic ignition of hydrogen peroxide and ethanolamine Ak, M. A.; Ulaş, Abdullah; Sumer, B.; Yazici, B.; Yildirim, C.; Gonc, L. O.; Orhan, F. E. (Elsevier BV, 2011-01-01) This paper presents the hypergolic ignition test results of a potential environmentally friendly liquid propellant consisting of hydrogen peroxide oxidizer (with a concentration of 85%) and ethanolamine fuel for use in rocket engines. Open cup drop tests were conducted to study the effect of amount of metal salt catalyst in fuel and the initial temperatures of fuel and oxidizer on the ignition delay time. To test the hypergolic ignition of bipropellant formulation in a real rocket engine environment, a pres...
A study on the effects of various combustion parameters on the mineral composition of Tuncbilek fly ash Akin, Suleyman Sener; Magalhaes, Duarte; Kazanç Özerinç, Feyza (Elsevier BV, 2020-09-01) This study investigated the mineral composition and morphology of ash obtained from laboratory equipment and power plant fly ash from a Turkish lignite. In accordance with this purpose, combustion experiments were conducted for different heating rates in a temperature range of 800-1000 degrees C using different laboratory scale equipment: drop tube furnace (DTF) (similar to 10(5) degrees C/s), wire mesh reactor (WMR) (similar to 10(3) degrees C/s) and muffle furnace (MF) (similar to 10 degrees C/min). The r...

Citation Formats

E. ABBASI-ATIBEH and A. Yozgatlıgil, “A study on the effects of catalysts on pyrolysis and combustion characteristics of Turkish lignite in oxy-fuel conditions,” FUEL, pp. 841–849, 2014, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/46777.