Year: 1888

page_text: Date of Application, 28th Aug., 1888
Specification Accepted, 19th Oct., 1888
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We, Baron ALBERT WILLEM SLOET VAN OLDRUITENBORGH, of 19 Avenue Rogier,
Liege, Civil Engineer, and OCTAVE NEEF-ORBAN of Ougrée, President of the Société
Anonyme des Aciéries d'Angleur, both in the Kingdom of Belgium, 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:-
This invention relates to the manufacture of cast iron and steel, and especially to
the purification of the metal from suiphur, in any smelting furnace such as a
cupola
or reverberatory furnace in gutters or runners and any receptacles for containing
the molten metal in order to convey the same in this state to converters provided with
acid linings, and irrespective of the mode of introducing the air necessary for refining
the bath in furnaces having a fixed or movable sole, such as are employed in the
Siemens-Martin, Martin-Riley, Danks, Ponsard, and Pernot processes, or any other
process carried out with an open hearth or sole for the manufacture of cast iron and
steel, and in any other receptacles for containing the refined metal in a state of fusion;
the smelting furnaces refining furnaces and converters employed being provided with
an acid lining.
This invention has also for its object the diminution of blisters in the cast metal.
In the fusion and refining of cast iron and steel, the sulphur contained in the raw
materials and fuel passes only partially into the slag or cinders and is often completely
incorporated with the metal. In order to eliminate all or part of this sulphur we
utilize the single or repeated action of oxides, hydrates, carbonates, nitrates, borates,
silicates, chromates, manganates, aluminates, titanates, tungstates, tannates, citrates,
tartrates, margarates, stearates, oleates, oxalates, acetates of potassium or sodium,
either separately or simultaneously, or mixed with other materials such as slag or
cinders, sand, iron oxides and ores as net with in commerce and in nature.
These salts, and more especially the carbonates and hydrates of potash and soda,
added to the fuel, raw materials, air, metal or its slag or cinders, have the property
of uniting with the sulphur and forming sulphurets of potassium and sodium fixed in
the slag or cinders first as sulphurets and afterwards transformed into sulphates in
presence of oxidizing materials, or volatilized at very high temperatures, and forming
moreover very fusible and purifying scoria.

page_text: The quantity of sodium and potassium salts to be added to the metal will be at
least one-sixth per cent. of the weight of the metal to be desulphurized, which
proportion in melting and refining furnaces can be increased at will up to the point
at which the quantity of these salts will present serious inconveniences with respect to
the preservation of the linings of the furnaces.
In general, it will be preferable not to exceed two per cent. of the weight of the
metal in every addition of salt.
The quantity of salt necessary which must be applied in one or more successive doses
according to the degree of desulphurization to be obtained, first in smelting furnaces
and afterwards in every transfusion of the metal as for example from the high furnace
or cupola to the ladles, converters or furnaces having a sole, and from these to the
casting ladles and so on, will vary according to the composition of the metal to be
purified and the fuel and raw materials.
The salis are introduced into the apparatus either through the feed and discharge
orifices, or through special orifices, or through twyers, either before, simultaneously
with, or after the metal to be purified, the raw materials or the fuel.
Apart from the mode of introducing these salts, and the moment at which this is
performed the fusibility and the purifying properties of the slag or cinders enable the
latter to become united with all the oxides dissolved in the metal, which tends to
augment its compactness and tenacity.
By this improved process we are enabled to manufacture steel purified to such an
extent that it contains less than 0.0001 of sulphur, and a quantity of carbon varying
from 003 to 2.25 per cent., and which permits of being hammered rolled, forged,
drawn, hardened and welded. These properties have heretofore been found only in
the finest steel made by means of skillets or in the Swedish Bessemer process by the
exclusive employment of raw materials which are very free from sulphur.
Having now particularly described and ascertained the nature of
our said
invention, and in what manner the same is to be performed we declare that what
we claim is:-
In the manufacture of cast iron and cast steel, the introduction of potassium or
sodium salts, raz-oxides, hydrates, carbonates, nitrates, borates, silicates, chromates,
manganates, aluminates, titanates, fungsiates, tanmates, citrates, tartrates, margarates,
stearates, oleates, oxalates, acetates, into smelting furnaces, refining furnaces, and
converters having an acid lining, or other receptacles which contain the molten metal,
substantially as, and for the purpose, described.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.