Finmet G4 2ln1s

FINMET

A LV IZO B O RLING D EC IN EL LAGA ESTO LA NO

FINMET PROCESS

The Fluidised Iron Ore Reduction(FIOR) process reduces iron ore to metallic iron at high temperature and pressure using reducing gases produced from reforming. improved tly by Fior de Venezuela and Voest Alpine (VAI) of Austria in 1991 culminating in the development of Finmet Process The primary aim is to improve the energy efficiency of FIOR by using top gas for ore heating and by removing CO from reformed gas as well as recycle gas.. The Finmet process is a multiple fluidized bed process which utilizes a H2 rich reducing gas 2 produced by steam reforming.

Iron fines under 12 mm

INPUTS AND OUTPUTS

FINMET PROCESS Hot Briquetted Iron (HBI)

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HOT BRIQUETTED IRON (HBI) 4

HBI

HBI overcome the problems associated with shipping and handling of DRI

Very much less porous Very much less reactive Does not suffer from the risk of self-heating

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FURNACES AND EQUIPMENT UTILIZE

FINMET PROCESS FLOWSHEET

double-roll briquetting press

lock-hopper system Reducing Reactors • equipped with internal cyclones

HBI

Recycling Gas Scrubber

Reducing Gas Furnace Air

Natural Gas

Recycle Gas Compressor CO2 removal system

Air Natural Gas

Steam Retonner

FINMET Process 11

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FINMET Process - concentrate/iron ore fines are fed into an ore drier - the feed is lifted to the top of the FINMET reactor structure and is charged to the reactor train - upper lockhoppers cycle continuously from ambient to reactor pressure - the ore is fed continuously to the reactors out of the lower lockhopper

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FINMET Process

- uses a train of four fluid bed reactors, with counter-current gas/solids ing down the reactor train

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feed concentrate enters the topmost reactor ( preheated to 550570C by reducing gas)

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The beneficiated ore is transferred downward between reactors via standpipes and is progressively reduced, first to FeO, and then finally to metallic Fe.

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The temperature in the bottom reactor (R1) is in the range of 780800C and final reduction to 93% metallisation is accompanied by carburization of some of the Fe to Fe3C (iron carbide).

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The hot, fine DRI is then transported by a sealed, pneumatic lift system, or riser, to the briquetter area where it is briquetted at temperatures greater than 650C in double roll briquetting machines to a density of approximately 5 tonne/m3.

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FINMET Process: Gas Flow

Recycled Top Gas

Fresh Reformer Makeup Gas

REDUCTION

RECYCLED GAS

MAKEUP GAS

Recycled gas

ADVANTAGES AND LIMITATONS

Low production costs with the use of low-cost iron ore fines

ADVANTAGES

Investment and energy consumption comparable with conventional DR processes Superior HBI quality featuring high Fe content and high degree of metallization

ADVANTAGES

Briquettes produced as intact single briquettes without breakage Low abrasion losses during handling and transport due to the highly compact nature of FINMET briquettes Industrially proven

Higher degree of metallization

DISADVANTAGES

This process were difficulties in achieving high degrees of reduction due to temperature control Briquetting of the product