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Drying and preheating processes of iron ore pellets in a traveling grate

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Abstract

A mathematical model of drying and preheating processes in a traveling grate was presented based on the laws of mass, momentum, heat transfer, and drying semiempirical relations. A field test was systematically carried out in a traveling grate. The effects of pellet diameter, moisture, grate velocity, and inlet gas temperature on the pellet bed temperature were studied. The average relative error between actual measurements and simulations is less than 7.97%, indicating the validity of the model.

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Abbreviations

a :

Surface area of pellets per cubic meter pellet bed, m2·m−3

α g :

Surface convection heat transfer coefficient, W·m−2·K−1

α v :

Volume convection heat transfer coefficient, W·m−3·K−1

a P , a W , a E , a N , and a S :

Discretization coefficients at points P, W, E, N, and S

b :

Discretization coefficient

C m :

Specific heat capacity of pellets, J·kg−1·K−1

C g :

Specific heat capacity of gas, J·m−3·K−1

C w :

Specific heat capacity of vapor, J·kg−1·K−1

d :

Pellet diameter, m

ΔH r :

Enthalpy of the oxidation reaction, J·mol−1

M :

Pellet humidity

M 0 :

Initial moisture of the pellet bed, %

Nu :

Nusselt number; Pr-Prandtl number

Re :

Reynolds number

T 0 :

Initial temperature of the pellet bed, K

Tm, Tg:

Temperature of pellet and gas, respectively, K

u :

Drying rate, kg·m−3·s−1 (dry basis)

V r :

Rate of magnetite reaction, mol·m−3·s−1

x i (i=1, 2, 3, 4, 5, 6):

Pellet diameter, gas velocity, gas temperature, initial moisture of pellets, layer number of the pellet bed, and time, respectively

γ :

Water evaporation enthalpy, J·kg−1

λ g :

Thermal conductivity of gas, W·m−1·K−1

ν g :

Kinematic viscosity of gas, m2·s−1

ρ g :

Gas density, kg·m−3

ρ H :

Pellet density, kg·m−3

τ :

Time, s

ω m :

Grate velocity, m·s−1

ω g :

Gas velocity, m·s−1.

References

  1. R.W. Young, M. Cross, and R.D. Gibson, Mathematical model of grate-kiln-cooler process used for induration of iron ore pellets, Ironmaking Steelmaking, 6(1979), No.1, p.1.

    CAS  Google Scholar 

  2. J.A. Thurlby, A dynamic mathematical model of the complete grate/kiln iron-ore pellet induration process, Metall. Trans. B, 19(1988), No.1, p.103.

    Article  Google Scholar 

  3. J.A. Thurlby, Gas flow and pressure balancing in modeling grate/kiln induration, Metall. Trans. B, 19(1988), No.1, p.113.

    Article  Google Scholar 

  4. J.A. Thurlby, Energy cost minimization in grate/kiln induration, Metall. Trans. B, 19(1988), No.1, p.123.

    Article  Google Scholar 

  5. M. Cross and R.W. Young, Mathematical model of rotary kilns used in the production of iron ore pellets, Ironmaking Steelmaking, 3(1976), No.3, p.129.

    Google Scholar 

  6. P.O. Pape, R.D. Frans, and G.H. Geiger, Magnetite oxidation kinetics and thermal profiles in a magnetite pellet plant cooler, Ironmaking Steelmaking, 3(1976), No.3, p.138.

    CAS  Google Scholar 

  7. J.H. Voskamp and J. Brasz, Digital simulation of the steady state behaviour of moving bed processes, Meas. Control, 8(1975), No.1, p.23.

    Google Scholar 

  8. N.A. Hasenack, P.A.M. Lebelle, and J.J. Kooy, Induration process for pellets on a moving strand, [in] Mathematical Process Models in Iron- and Steel-Making, Amsterdam, 1975, p.6.

  9. J.A. Thurlby, R.J. Batterham, and R.E. Turner, Development and validation of a mathematical model for the moving grate induration of iron ore pellets, Int. J. Miner. Process., 6(1979), No.1, p.43.

    Article  CAS  Google Scholar 

  10. M. Cross and K.C. Wade, Computer simulation of iron ore pellet induration with additives, [in] 5th International Symposium on Agglomeration, Philadelphia, 1989, p.291.

  11. M. Cross and P. Blot, Optimizing the operation of straight-grate iron-ore pellet induration systems using process models, Metall. Mater. Trans. B, 30(1999), No.4, p.803.

    Article  Google Scholar 

  12. M. Barati, Dynamic simulation of pellet induration process in straight-grate system, Int. J. Miner. Process., 89(2008), No.1–4, p.30.

    Article  CAS  Google Scholar 

  13. S.K. Sadrnezhaad, A. Ferdowsi, and H. Payab, Mathematical model for a straight grate iron ore pellet induration process of industrial scale, Comput. Mater. Sci., 44(2008), No.2, p.296.

    Article  CAS  Google Scholar 

  14. S. Majumder, P.V. Natekar, and V. Runkana, Virtual indurator: A tool for simulation of induration of wet iron ore pellets on a moving grate, Comput. Chem. Eng., 33(2009), No.6, p.1141.

    Article  CAS  Google Scholar 

  15. H.Q. Zhang, Study on process parameters of drying and preheating iron oxidized pellets in grate-kiln, Min. Metall., 14(2005), No.2, p.59.

    CAS  Google Scholar 

  16. J.X. Feng, Z.B. Sun, Y. Zhang, et al., Mass and thermal balance and energy-saving analysis of the grate-kiln system, Sintering Pelletizing, 32(2007), No.6, p.29.

    Google Scholar 

  17. Y. Zhang, J.X. Feng, Z.Y. Xie, et al., Energy and exergy analysis of iron ore pellets induration in the coal-fired rotary kiln, J. Iron Steel Res. Int., 16(2009), Suppl.2, p.303.

    Google Scholar 

  18. Y. Zhang, J.X. Feng, Z.Y. Xie, et al., The first and second law analysis of thermodynamics analysis for iron ore pellets induration in the traveling grate, J. Iron Steel Res. Int., 16(2009), Suppl.2, p.322.

    Google Scholar 

  19. J.Y. Fu, Y.T. Li, C.W. Jiang, et al., Oxidation kinetics of magnetite concentrate pellets, J. Cent. South Univ. Sci. Technol., 35(2004), No.6, p.950.

    CAS  Google Scholar 

  20. H.W. Zheng, The Research of Drying and Preheating Process in Grates [Dissertation], University of Science and Technology Beijing, Beijing, 2007, p.24.

    Google Scholar 

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Authors and Affiliations

  1. School of Mechanical Engineering, University of Science and Technology Beijing, Beijing, 100083, China

    Jun-xiao Feng, Yu Zhang, Hai-wei Zheng, Xiao-yan Xie & Cai Zhang

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  1. Jun-xiao Feng
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  2. Yu Zhang
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  3. Hai-wei Zheng
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  4. Xiao-yan Xie
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Correspondence to Jun-xiao Feng.

Additional information

This work was financially supported by the National High-Tech Research and Development Program of China (No.2007AA05Z215).

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Feng, Jx., Zhang, Y., Zheng, Hw. et al. Drying and preheating processes of iron ore pellets in a traveling grate. Int J Miner Metall Mater 17, 535–540 (2010). https://doi.org/10.1007/s12613-010-0354-0

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  • DOI: https://doi.org/10.1007/s12613-010-0354-0

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