Numerical Simulations of Combustion and Decomposition Processes in Precalciner with Two Types of Locations of Jetting Coal Pipes

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To reduce energy consumption, numerical simulations of combustion and decomposition processes in a precalciner were carried out with two types of locations of jetting coal pipes. In Euler coordinate system the gas phase is expressed with k-ε two-equation model, in Lagrange coordinate system the solid phase is expressed with discrete phase model (DPM), the chemical reaction is expressed with species transport model, and the radiation is expressed with P1 radiation model. For the base case the predicted burn-off rate of pulverized coal was 86%, and the decomposing rate of calcium carbonate was 92.9%, which are in accordance with actual measurement engineering data. The results show that when the jetting coal pipes are above the tertiary air inlet, the flow pattern of coal streams is more rational in the precalciner, being beneficial to the coal burn fully, resulting in a high temperature zone, around which the calcium carbonate decompose rapidly, than that when the jetting coal pipes are far away from the tertiary air inlet.

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Periodical:

Edited by:

Yuning Zhong

Pages:

428-433

Citation:

S. X. Mei et al., "Numerical Simulations of Combustion and Decomposition Processes in Precalciner with Two Types of Locations of Jetting Coal Pipes", Applied Mechanics and Materials, Vol. 235, pp. 428-433, 2012

Online since:

November 2012

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$38.00

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