Assessment of thermogravimetric methods for calculating coke combustion-regeneration kinetics of deactivated catalyst

The pulverized coal injection (PCI) is widely utilized in the iron-making blast furnaces for its economic and environmental advantages. However, due its complexity, flow dynamics and chemical kinetics of PCI inside the raceway has not been well understood. Combustions of PCI and coke inside the raceway can be influenced by tuyere operation parameters. In this paper, a comprehensive three dimensional (3-D) multiphase flow computational fluid dynamics (CFD) model was utilized to investigate the PCI and coke combustion in the lower part of a blast furnace. Systematic parametric studies were conducted to analyze the effects of the natural gas injection, coal injection, PCI rate, and oxygen enrichment on the combustion performance, which include coal burnt-out rate, coke consumption rate, raceway shape, raceway temperature and etc.

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Coke combustion kinetics of spent Pt-Sn/Al2O3 catalysts in propane dehydrogenation

Korean Journal of Chemical Engineering ◽

10.1007/s11814-020-0536-z ◽

2020 ◽

Vol 37 (9) ◽

pp. 1490-1497

Author(s):

Pajri Samsi Nasution ◽

Jae-Won Jung ◽

Kyeongseok Oh ◽

Hyoung Lim Koh

Keyword(s):

Propane Dehydrogenation ◽

Combustion Kinetics ◽

Coke Combustion ◽

Kinetics Of

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Kinetics of Gaseous Product Formation in the Coke Combustion of a Fluidized Catalytic Cracking Catalyst

Industrial & Engineering Chemistry Research ◽

10.1021/ie980764b ◽

1999 ◽

Vol 38 (9) ◽

pp. 3255-3260 ◽

Cited By ~ 9

Author(s):

José M. Arandes ◽

Iñaki Abajo ◽

Inmaculada Fernández ◽

Danilo López ◽

Javier Bilbao

Keyword(s):

Catalytic Cracking ◽

Product Formation ◽

Gaseous Product ◽

Fluidized Catalytic Cracking ◽

Coke Combustion ◽

Kinetics Of

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Kinetics of coke combustion during temperature-programmed oxidation of deactivated cracking catalysts

Catalyst Deactivation, Proceedings of the 7th International Symposium - Studies in Surface Science and Catalysis ◽

10.1016/s0167-2991(97)80178-4 ◽

1997 ◽

pp. 383-390 ◽

Cited By ~ 6

Author(s):

Cam Le Minh ◽

Chaoen Li ◽

Trevor C. Brown

Keyword(s):

Temperature Programmed Oxidation ◽

Coke Combustion ◽

Temperature Programmed ◽

Kinetics Of ◽

Cracking Catalysts

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Direct observations of radiation-enhanced transformations in glass

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075543 ◽

1983 ◽

Vol 41 ◽

pp. 354-355

Author(s):

J. F. DeNatale ◽

D. G. Howitt

Keyword(s):

Glass Matrix ◽

Diffusion Mechanism ◽

Bubble Formation ◽

Silicate Glasses ◽

Phase Decomposition ◽

Direct Observations ◽

Thin Foils ◽

Oxygen Bubble ◽

Electron Energy Loss ◽

Kinetics Of

The electron irradiation of silicate glasses containing metal cations produces various types of phase separation and decomposition which includes oxygen bubble formation at intermediate temperatures figure I. The kinetics of bubble formation are too rapid to be accounted for by oxygen diffusion but the behavior is consistent with a cation diffusion mechanism if the amount of oxygen in the bubble is not significantly different from that in the same volume of silicate glass. The formation of oxygen bubbles is often accompanied by precipitation of crystalline phases and/or amorphous phase decomposition in the regions between the bubbles and the detection of differences in oxygen concentration between the bubble and matrix by electron energy loss spectroscopy cannot be discerned (figure 2) even when the bubble occupies the majority of the foil depth.The oxygen bubbles are stable, even in the thin foils, months after irradiation and if van der Waals behavior of the interior gas is assumed an oxygen pressure of about 4000 atmospheres must be sustained for a 100 bubble if the surface tension with the glass matrix is to balance against it at intermediate temperatures.

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