IMPROVEMENTS IN UTILIZING RESI- DUAL AND OTHER OXIDES OF IRON
Year: 1877

page_text: LETTERS PATENT to John Heath Bald, of Hebburn-on-Tyne, in the County of
Durham, Chemist, for the Invention of "IMPROVEMENTS IN UTILIZING RESI-
DUAL AND OTHER OXIDES OF IRON."
Sealed the 1st Juno 1877, and dated the 28th March 1877.
PROVISIONAL SPECIFICATION left by the said John Heath Bald at the
Office of the Commissioners of Patents on the 28th March 1877.
JOHN HEATH BALD, of Hebburn-on-Tyne, in the County of Durham, Chemist.
"IMPROVEMENTS IN UTILIZING RESIDUAL AND OTHER OXIDES OF IRON."
The object of my Invention is to utilize such residual and other oxides of iron as
are in a finely divided, powdery, or pulverulent condition, and which heretofore have
been unsuited for smelting and working without previous deoxidation. For that
purpose I mix the said oxides with caustic lime, and add theroto a little water
when the said oxides do not contain a sufficient quantity of moisture; I then dry
the mixed mass in contact with or in an atmosphere containing carbonic acid gas. In
this way the caustic lime is converted into carbonate of lime, and the mass is
rendered sufficiently hard to withstand the burden of the blast furnace, and made
fit for treatment by any known or desired means.
In practice I add to residual ores from cupreous pyrites from five to ten per cent.
of caustic lime, and about five per cent. of water; and after thorough mixing under
edge runners, or by any other suitable means, I spread the said mixed mass,
divided into suitable pieces or lumps on a floor, and dry it in an atmosphere containing
carbonic acid, obtained preferably from the waste products of combustion used to
heat the drying floors on which the mixed mass is spread.
0 SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Heath Bald in the Great Seal Patent Office on the
28th September 1877.
JOHN HEATH BALD, of Hebburn-on-Tyne, in the County of Durham, Chemist.
"IMPROVEMENTS IN UTILIZING RESIDUAL AND OTHER OXIDES OF IRON."
Da11

page_text: The object of my Invention is to utilize such residual and other oxides of iron as
are in a finely divided, powdery, or pulverulent condition, and which heretofore
have been unsuited for smelting and working without previous deoxidation. For
that purpose I mix the said oxides with caustic lime, and add thereto a little water
when the said oxides do not contain a sufficient quantity of moisture. I then dry
the mixed mass in contact with or in an atmosphere containing carbonic acid gas.
In this way the caustic lime is converted into carbonate of lime, and the mass is
rendered sufficiently hard to withstand the burden of the blast furnace and made
fit for treatment by any known or desired means.
When treating the residual oros from cupreous pyrites, I add seven and a half
per cent. of caustic lime. I prefer that the lime should be slacked, made into a
cream, and added to the ore through a sieve, so as to prevent pieces of flint or other
foreign matter and undecomposed limestone becoming mixed with the said bre; a pro-
portion of water equal to ten per cent. of the weight of the ore is added in addition
to the water required to slake the lime. The ore and lime are now thoroughly
mixed together under edge runners or by other means, and the mixed mass
spread on a drying floor to a depth not exceeding four inches. I find in drying the
mixed mass that if the drying floor is kept at a temperature of about 200° F. the
best result is obtained. Whilst the mass is drying it is kept in contact with an
atmosphere of carbonic acid gas or, as I prefer, when the mixed mass has been
thoroughly dried, which usually occupies twenty-four hours, it is broken up into
pieces, and removed to a chamber and subjected to the action of carbonic acid gas,
which is best obtained from the products of combustion used to heat the drying floor.
Oxides of iron, other than the residual ores from cupreous pyrites, are treated in
the manner above specified, except that the amount of water to be added will
vary with the dryness of the ores.
Having now described my Invention in such manner that others will be enabled
to carry the same into effect, I claim the improvements in treating residual and
other oxides of iron, substantially in the manner and for the purposes set forth.
In witness whereof, I; the said John Heath Bald, have hereunto set my
hand and seal, the Twenty-sixth day of September, in the year of our Lord
One thousand eight hundred and seventy-seven.