Assessment of catalyst deactivation model for sulfur retention in fluidized bed combustors

Degirmenci, E
Gogebakan, Y
Selçuk, Nevin
An improved version of a combustion-desulfurization model for fluidized bed combustors burning high ash and sulfur content low quality lignite in its own ash with the addition of limestone is presented. The desulfurization model considers sulfur retention by both limestone and ash and is based on first order catalyst deactivation where the kinetics of desulfurization is described by two rate constants; one for the initial surface reaction, the other for the rate of pore plugging or deactivation. The accuracy of the complete model with experimentally determined deactivation rate constants was tested by applying it to a 0.3 MWt AFBC test rig and comparing its predictions with measurements. Comparisons show that the model produces reasonably accurate predictions of sulfur retention provided that the rate constants are determined experimentally under the fluidized bed combustor operating conditions.


Investigation of ash deposition in a pilot-scale fluidized bed combustor co-firing biomass with lignite
Gogebakan, Zuhal; Gogebakan, Yusuf; Selçuk, Nevin; Seliuk, Ekrem (2009-01-01)
This study presents the results from investigation of ash deposition characteristics of a high ash and sulfur content lignite co-fired with three types of biomass (olive residue, 49 wt%; hazelnut shell, 42 wt%; and cotton residue, 41 wt%) in 0.3 MWt Middle East Technical University (METU) Atmospheric Bubbling Fluidized Bed Combustion (ABFBC) Test Rig. Deposit samples were collected on all air-cooled probe at a temperature of 500 degrees C. Samples were analyzed by SEM/EDX and XRD methods. The results reveal...
Modeling of a bubbling AFBC with volatiles release
Selçuk, Nevin; Gogebakan, Y (2003-03-01)
comprehensive model for continuous combustion of lignite with wide size distribution burning in its own ash in an atmospheric bubbling fluidized bed combustor (ABFBC) has been presented and used to correlate the data from a 0.3 MW ABFBC test rig. The model consists of submodels for hydrodynamics, volatiles release and combustion, char combustion, particle size distribution, entrainment and elutriation and is based on conservation equations for energy and chemical species. The volatiles release model is base...
Modelling of ECBM recovery from Amasra Coalbed in Zonguldak Basin, Turkey
Sınayuç, Çağlar (2018-01-01)
Bartin-Amasra coal field was found convenient for enhanced coalbed methane (ECBM) recovery among the other fields in Zonguldak Coal Basin, Turkey. The lithologic information were examined and the depths of the coal seams and the locations of the wells were visualized to perform a reliable correlation between 63 coal layers existed in the area. The initial methane in place found in the coal layers both in free and adsorbed states were estimated using probabilistic simulations resulted in possible reserve (P1...
Mutual activation of blast furnace slag and a high-calcium fly ash rich in free lime and sulfates
Sahin, Murat; Mahyar, Mahdi; Erdoğan, Sinan Turhan (2016-11-15)
Alkaline activation of fly ash and blast furnace slag has gained interest due to a desire to avoid Portland cement in mixtures. Outstanding mechanical performance and durability is reported, but often when the activator dosage is high which can have various negative environmental impacts that can overshadow the carbon reduction benefit. This study investigates the use of a ground slag, and a high-lime fly ash, rich in free lime and sulfates, to activate each other and render mortars which don't incorporate ...
Cofiring lignite with hazelnut shell and cotton residue in a pilot-scale fluidized bed combustor
Gogebakan, Zuhal; Selçuk, Nevin (2008-05-01)
In this study, cofiring of high ash and sulfur content lignite with hazelnut shell and cotton residue was investigated in 0.3 MWt METU Atmospheric Bubbling Fluidized Bed Combustion (ABFBC) Test Rig in terms of combustion and emission performance of different fuel blends. The results reveal that cofiring of hazelnut shell and cotton residue with lignite increases the combustion efficiency and freeboard temperatures compared to those of lignite firing with limestone addition only. CO2 emission is not found se...
Citation Formats
E. Degirmenci, Y. Gogebakan, and N. Selçuk, “Assessment of catalyst deactivation model for sulfur retention in fluidized bed combustors,” COMBUSTION SCIENCE AND TECHNOLOGY, pp. 95–111, 2000, Accessed: 00, 2020. [Online]. Available: