FINMET, une technologie de réduction de fines de minerai pour la production de préréduits briquetés à chaud

Zeller, Susanne; Deimek, G.; Milionis, K.; Gould, Lawrence; Whipp, R.H.

doi:10.1051/metal/199895040425

Cited by 5 publications

(5 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Some of these fluidized bed processes (e.g. FIOR process, FINMET ® process 2) and Circored process) produce hot briquetted iron, whereas others (e.g. Iron Carbide process) produce Fe 3 C. Both products can be melted in electric arc furnaces.…”

Section: Introductionmentioning

confidence: 99%

“…Thus a strong interest in the kinetics of reduction by a reducing gas containing CO and CH 4 exists. Some authors tested the kinetics of reduction by mixtures of H 2 , CO, CO 2 and H 2 O, [14][15][16] others the carburization of iron ore fines by adding CH 4 to the reducing gas. 17,18) Industrial scale fluidized bed reduction units operate at elevated pressure, but only a few kinetic studies for the reduction of iron ore in fluidized beds were done at elevated pressures.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

An Experimental Study on the Kinetics of Fluidized Bed Iron Ore Reduction.

Habermann¹,

Winter²,

Hofbauer³

et al. 2000

ISIJ International

View full text Add to dashboard Cite

To optimize existing iron ore reduction processes or to develop new ones, it is necessary to know the reduction kinetics of the iron ore of interest under the relevant operating conditions. In this work the reduction kinetics of hematite fine iron ore was studied for industrial-scale processes using the fluidized bed technology. Especially designed batch tests were performed in a laboratory-scale fluidized bed reactor fluidized with H 2 , H 2 O, CO, CO 2 , N 2 at atmospheric and elevated pressures to simulate the relevant process conditions. To obtain the reduction rates and the degree of reduction, the concentrations of H 2 O, CO, and CO 2 in the outlet gas were analyzed by FT-IR spectroscopy.Preliminary reduction tests showed a strong effect of the sample weight on the reduction rates, especially in the early stages of reduction. The optimum sample weight was determined by partly replacing the hematite with silica sand. Additionally, the silica sand provided a constant and stable flow pattern throughout the reduction tests. The effects of temperature, gas composition, particle size and pressure on the rates of reduction were tested and discussed.Rate analysis showed the existence of two phases with different rates during the reduction tests. Additional investigations (microscope analysis, SEM) demonstrated that in the first phase the rates were controlled by mass transport in the gas phase and in the second phase by the reduction process within the small grains of the iron ore particles.KEY WORDS: iron ore reduction; high temperature fluidized bed; reduction kinetics; elevated pressure; H 2 -CO gas mixture.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

An Experimental Study on the Kinetics of Fluidized Bed Iron Ore Reduction.

Habermann¹,

Winter²,

Hofbauer³

et al. 2000

ISIJ International

View full text Add to dashboard Cite

show abstract

“…The reduction in fluidized bed reactors offers the advantages of no feed agglomeration, uniform temperature in the reactor, and excellent heat and mass transport. Some of these fluidized bed processes (e.g., FIOR process, FINMET process, [2] and Circored process) produce hot briquetted iron, whereas others (e.g., Iron Carbide process) produce iron carbide. Both products can be melted in electric arc furnaces.…”

Section: Introductionmentioning

confidence: 99%

Iron ore reduction in a continuously operated multistage lab-scale fluidized bed reactor—Mathematical modeling and experimental results

Thurnhofer

Schuster

Löffler

et al. 2006

Metall Mater Trans B

View full text Add to dashboard Cite

Industrial-scale fluidized bed processes for iron ore reduction (e.g., FIOR and FINMET) are operated by continuous feeding of ore, while laboratory tests are mostly performed under batchwise operation. The reduction behavior under continuous operation is influenced by both the residence time of the iron ore particles and the reduction kinetics, which is obtained by batch tests. In a mathematical model for such a process, the effect of both phenomena has to be considered. The residence time distribution of iron ore particles in a laboratory fluidized bed reactor was obtained by measuring the response of a step input and described by mathematical models similar to a continuously stirred tank reactor. In the same reactor, reduction tests with continuous feeding of iron ore were performed. Based on batch tests in a fluidized bed reactor, a mathematical model was developed to describe the kinetics of iron ore reduction under fluidized bed conditions. This kinetic model was combined with the fluidized bed reactor model to describe continuous iron ore reduction. In this detailed model, the change of gas composition while rising in the fluidized bed was considered. The degree of reduction and the gas conversion for reactors in series were calculated. The results obtained by the mathematical model were compared with experimental data from the laboratoryscale reactor.

show abstract

“…1,2 In non-blast furnace ironmaking, fluidised bed reactors are used as reduction or prereduction equipment in such processes as Circofer, FINMET and FINEX. [3][4][5][6] However, sticking between iron ore particles, resulting in partial or complete defluidisation during the reduction process, is a serious problem for continuous operation and high productivity. 7,8 To investigate the mechanism of sticking, a large number of studies have been carried out.…”

Section: Introductionmentioning

confidence: 99%

Sticking behavior caused by sintering in gas fluidisation reduction of haematite

Zhong

Wang

Gong

et al. 2012

Ironmaking & Steelmaking

View full text Add to dashboard Cite

The sticking of haematite and iron powder during the fluidisation process was investigated using a visual fluidised bed reactor. The results showed that the amount of iron needed to stick decreased with increasing fluidisation temperature. Owing to no iron whisker formation in the experiments, the sticking phenomenon was discussed in the special case where iron morphology was dense or porous, and much attention should be paid to the effect of sintering of iron-iron contact on sticking, especially, surface nano-/microstructures of fresh iron that caused an increase in particle cohesiveness and sticking tendency. It was assumed that haematite covered with iron transformed into cohesive particles that self-agglomerated above minimum sintering temperature. Owing to the interface reaction induced, the sticking temperature of haematite was always lower than that of iron powder in the same size ranges. On the basis of sintering with surface diffusion mechanism, the tendency of sticking was enhanced by reduction reaction through reinforcing mass transfer on particle surface. Therefore, when iron whiskers were suppressed, sticking phenomenon was viewed as the agglomeration fluidisation among cohesive particles under sintering action.List of symbols d p particle diameter/m g acceleration of gravity/m s 22 M molar mass/kg mol 21 R radius of curvature of minute particles/m T m melting point of minute particles/K T 0 m melting point of flat solid/K u mf minimum fluidisation velocity/m s 21 c liquid/solid interface tension/J m 22 D l s H m molar enthalpy of fusion/kJ mol 21 m viscosity of gas/Pa s r density of solid/kg m 23 r g density of particles/kg m 23 r s density of particles/kg m 23

show abstract

FINMET, une technologie de réduction de fines de minerai pour la production de préréduits briquetés à chaud

Cited by 5 publications

References 0 publications

An Experimental Study on the Kinetics of Fluidized Bed Iron Ore Reduction.

An Experimental Study on the Kinetics of Fluidized Bed Iron Ore Reduction.

Iron ore reduction in a continuously operated multistage lab-scale fluidized bed reactor—Mathematical modeling and experimental results

Sticking behavior caused by sintering in gas fluidisation reduction of haematite

Contact Info

Product

Resources

About