dear friend.

there are many such processes.

Many use a rotary furnace and coal.

Other use a fludized reactor with different circuits.

The FIOR prcess installed in SIDOR 30 years ago is now public domain, it is a circulating fluidized Bed (sprouting).

From this base many have developed their own version.

Voest, I am jnot sure but I believe they call it Cicofer.

LUrgi (now Outucompu)

I believe Outucumpu names his Circored.

There are many books concerning Iron Ore direct reduction processes, many handle pellets and large particles, others play with fines. You might try a search in Amazon.com.

From the Hogganas and Madaras

HYL I , II and III Midrex

Purofer

HIB

FIOR

Corex

and all sort of Clones and Mixes

Recent developments like

Voest Posco

and a promising new process

HISMELT

Regards,

Marco A. Flores V. ■

Fines are particles smaller than 1/8 aprox 1 mm

Powder is finer from ,- 200 on , powders are easily airborne.

fines contain powders

powders are normally considered a nuisance as they get carried over to the dust colectors and are difficult to handle .

once in sponge form they are higly phirophoric and extremely dangerows if airborne.

marco ■

As you might guess the definition of powder vs fines is a bit shaky. Where you draw the line depends on your particular equipment design and final purpose.

Ex. In an electric furnace that feeds sponge iron continuosly into the melted bath, through the roof, dust would be defined as the fraction of material that is airborn and ends up in the dust collection.

This fraction will not only depend on particle size , but also in the particular arrangenemt of the dust collectror chute the electrodes, and the feeding chute.

It is easy to calculate the airborne particle size.

This will give you a worst case scenario of the amount of sponge iron that will go into the dust collector as direct metalic losses.

Now you must finf out what the collector efficiency is, as only a percentage of the potentially airborne particles will be collected.

That is not simple.

The second point regarding fines and dusts is the impingement point into the melted bath, and the location of the oxygen lances.

A fraction of the sponge iron will not be incorporated into the bath , but will float in the slag and be carried out of the furnace in continuos de-slagging furnaces. Either pushed by the Oxygen lances momentum, or carried out by the slag's natural agitation.

This floated sponge can make a good percent; in some cases we had up to 8% that goes out in metalic form, added to the percentage that goes out as iron oxide.

An oxidicing slagg can have 50 % iron oxide.

I am no expert in this area, but it seems that in the steel induistry these losses are considered a fact of life and little formal effort is made to reduce or recover them other than crushing and magnetic recovery of the slag. No effort is made to use the remaining temperature on the slag to try to react the iron oxide, after leaving the furnace, or to precipitate the metalic iron.

Some years ago we started an R&D project, but after I left the company, I heard this was eventually considered a flop and the project was scrapped, a pity, there were apparently more than 6 Million US Dollars a year to be saved.

I can only hope that they took the project to at least initial experimental stages, and that the project itself proved unprofitable and not because of lack of champion or sponsor..

Regards

Marco A. Flores Verdugo

Regards

Marco ■

recent events might be of interest to you if you handle hot iron ore dust ,

temperature perception only by radiation , might not be enough . the material upper layers , can act as an insulator hiding layers of red hot material that can be extremely dangerous if unproperly handled, have respect of any accumulated dust that might have a hot origin , handle it af it was hot , even if it looks cold.

Marco ■

Furthermore if you use lime or dolomite as an additive your Ir readings might as well be off as the spectral emisivity of iron ore and that of lime will differ , look for long wavelength IR sensors ■

To extend this discussion further - then what constitutes the difference between metal filings and powders such as iron? ■

I believe there are multiple processes to produce metal powders . Some use sprayed liquid metal , others abrade solid metal and then separate the abrasive from the metal. Whatever the method , handle it with care , aluminum dust can catch fire spontaneously, so can iron.

filings as far as i know are the product of machining solid metal . shavings are also obtained by machining a solid metal piece with a milling machine or a lathe.

Filings are not normally contaminated with oils , shavings always are.

Marco ■

Sponge iron has been made for about 2000 years .

there are many that claim they have the new process and end up with a clone of the past or existing processes

gas and coal based proceses, most of them with expired patents exists , and many of then are only refried versions of old processes or convinations of them.

FIOR,

Purofer,

NIPON,

MIDREX.

HYL1,2,3,

Hytemp,

Arex

COREX,

Madaras,

Hogganas,

Voest

Hismelt

CircoRed

InRed etc.

If you have anything that will not depend on natural gas and that consumes less than 2 gcal per ton , use waste ores , or waste gases , and can prove it can work for at least a year without shuttdowns , the world will beat a path to your door.

Good luck. ■

Originally Posted by adarsh garg

Does anyone know the process of making sponge iron fron iron ore powder(ash)...It is known as powder technology

Thanks,

Adarsh garg

First it need press into block then burned in the tunnel furnace,and the block need put into crucible,and the flotation.

www.cn-steelplate.com ■