Improvements in or relating to the Utilization of Ore Dust, or of Perished Ore.
Year: 1898

page_text: Date of Application, 26th Apr., 1898-Accepted, 4th June, 1898
COMPLETE SPECIFICATION.
Improvements in or relating to the Utilization of Ore Dust, or of
Perished Ore.
We, PETER KLEBER, of 23, Taunus Strasse, Mainz, Manufacturer, and DAGOBERT
TIMAR, 27/28, Luisen Strasse, Berlin, Patent Agent, both in the German
Empire, do hereby declare the nature of this invention and in what manner the
same is to be performed, to be particularly described and ascertained in and by the
following statement :-
Our invention relates to improvements in obtaining metals, especially iron, from
the ore dust.
As is well known iron and the like ores are smelted for the obtaining of pig-iron
and so forth in their natural condition; a separation of the crude ore from its non-
metallic constituents is not worth while. The ore is placed in the blast furnace by
filling in the said ore together with the flux and the fuel, such as coke, at the
top in regular proportions, and the slag and the fluid pig-iron are drawn off
below.
For this process of iron smelting hitherto only ore in pieces has been available.
The use of pulverized ore frequently containing a very high percentage of available
metal, and which occurs in quantity at the mines, and of weathered or perished ore
has been hitherto regarded as impossible, and for the bestowal of such ores large
pieces of ground have been uselessly occupied.
Many experiments have been made with the view of rendering the metal contained
in the dust of the ore or in the perished ore available, but without any material
advantage. The methods hitherto proposed are some of them only to be carried out
with difficulty, or are impossible of realization, and partly they involve too great a
cost, so that in practice matters remained as before.
The treatment either by the wet or the dry method proved successful only in the
case of very valuable metals.
+
The process set forth in this specification enables a complete utilization to be made
of the pulverized ore; this process is moreover very simple and cheap, because only
such materials are requisite or are preferably made use of, which themselves can be
applied irrespective of the process as a useful addition in metallurgical processes.
The pulverized ore is mixed with quicklime, and if necessary also with silicates in
proper proportion, and is then further treated with a hot solution of a flux and pre-
ferably with such a flux as is capable of forming a protective slag. The material so
prepared is then formed into blocks and placed upon waggons. The blocks are taken
direct from the press in the fresh state without being dried as has hitherto been
found necessary, and brought, together with the waggon, into a closed space in order
there to be treated with superheated steam at high pressure. The flux such as
chloride of sodium, soda or the like forms in the heat a protective coating around
the block, and thus protects the same from the otherwise unavoidable perishing.
After a short space of time usually from three to four hours, the combination of the
oxide metal, silicate and the like has become complete. When the pressure has been
taken off the pressure chamber, the blocks of ore thus prepared can be taken out and
smelted with coke without further addition. The use of coke for the smelting may
be obviated by mixing with the pulverized ore before the same is pressed, a suitable

page_text: proportion of the waste product obtained in the manufacture of coke, the so-called
coke dust. In this manner each grain of ore is intimately surrounded by fuel and
silicates and the like, and consequently the smelting of the ore proceeds very easily
and quickly; moreover at the same time the carbonizing of the iron which is of such
importance in the smelting, is effected at the same time. By this process the
roasting of the ore is effected at the same time, seeing that the metallic oxide
silicate and the like, are already fused partly together; moreover each grain of ore
is so surrounded with the additional substances that it is better intermixed with the
coke and the flux than is ever possible in the usual smelting of ore. The circum-
stance is of especial technical importance that in addition to the lime, which is
requisite as a flux in the ordinary process, and may consequently be left out of con-
sideration, blast furnace slag which is rich in silicates, lime and alumina and the like
can always be used over again and be recovered again. Blast furnace slag is a by-
product in every iron works, and the other additional matters are requisite as slag
forming material in any case, so that there remains almost exclusively only the cost
of labour for the preparation of the blocks, which cost is a very small one, to be
taken into account. Consequently the utilization of the ore according to this process
may be regarded as one of extreme value.
Having now particularly described and ascertained the nature of our invention
and in what manner the same is to be performed, we declare that what we
claim is:-
The improved process for the obtaining of metal, especially of iron, from the ore
dust, consisting essentially in mixing the said dust with lime, and if necessary, with
silicates, and then compounding it by aid of a hot solution of flux into a plastic mass,
which after it has been pressed into blocks is treated in pressure chambers with
superheated or high pressure steam, and thus hardened, the said blocks being
subsequently smelted with or without the addition of coke substantially as
described.
W. P. THOMPSON & Co.,
322, High Holborn, London, W.C., Patent Agents for the Applicants.