IMPROVEMENTS IN UTILISING OR TREATING CERTAIN ORES OR RESIDUARY OXIDES OF IRON
Year: 1877

page_text: LETTERS PATENT to Robert Main, Manager of the Carnbroe Ironworks,
Coatbridge, in the County of Lanark, North Britain, for the Invention of
"IMPROVEMENTS IN UTILISING OR TREATING CERTAIN ORES OR RESIDUARY
OXIDES OF IRON."
Sealed the 24th July 1877, and dated the 5th February 1877. ·
PROVISIONAL SPECIFICATION left by the said Robert Main at the Office of
the Commissioners of Patents on the 5th February 1877.
ROBERT MAIN, Manager of the Carnbroe Ironworks, Coatbridge, in the County of
Lanark, North Britain. " IMPROVEMENTS IN UTILISING OR TREATING CERTAIN
ORES OR RESIDUARY OXIDES OF IRON."
This Invention relates to ores or residuary oxides of iron, which from being in a
state of minute divisions it has hitherto been found very difficult to smelt or other-
wise utilise.
Amongst ores or oxides of the class referred to are the iron sands of Taranaki
and Canada, some hematite ores, and what is known as purple ore," the last
named being a residuum of what is known as the "wet" process of treating iron
and copper pyrites.
The Invention consists in mixing iron ores or oxides of the kind referred to with
blackband or clay band, or other ironstone, and in calcining the mixture in the
manner ordinarily practised with the ironstone alone, or in any other suitable
manner, prior to putting it into the blast furnace.
In carrying out the Invention when adopting the ordinary open heap or open
hearth method of calcining the ironstone a suitable proportion of the finely divided
iron ore or oxide is roughly mixed with the ironstone and with the necessary pro-
portion of coal, for example, by tipping upon the heap in a regular manner one
hutch of the finely divided ore or oxide for every three, four, or other number of
hutches of the ironstone, or in any other convenient manner.
During the calcination of the ironstone the finely divided ore or oxide mixed
71

page_text: therewith, being raised to a high temperature, becomes agglutinated and formed into
lumps suitable for charging along with the calcined ironstone into the smelting
furnace.
By the described process the "purple ore,” or similar oxide, becomes freed from
the large per-centage of water usually adhering to it, and much of the sulphur,
arsenic, and copper associated with it is volatilised, so that the quality of the iron
obtained is improved.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Robert Main in the Great Seal Patent Office on the 2nd August
1877.
ROBERT MAIN, Manager, of the Carnbroe Ironworks, Coatbridge, in the County
of Lanark, North Britain. 'IMPROVEMENTS IN UTILISING OR TREATING CERTAIN
ORES OR RESIDUARY OXIDES OF IRON."
My said Invention relates to ores or residuary oxides of iron, which from being
in a state of minute division it has hitherto been found very difficult to smelt or
otherwise utilise.
Amongst ores or oxides of the class referred to are the iron sands of Taranaki
and Canada, some hematite ores, and what is known as "purple ore," the last
named being a residuum of what is known as the "wet" process of treating iron
and copper pyrites.
My Invention consists in mixing iron ores or oxides of the kind referred to with
black band or clayband, or other ironstone, and in calcining the mixture in the
manner ordinarily practised with the ironstone alone, or in any other suitable
manuer, prior to putting it into the blast furnace.
In carrying out my Invention when adopting the ordinary open heap or open
hearth method of calcining the ironstone a suitable proportion of the finely divided
iron ore or oxide is roughly mixed with the ironstone and with the necessary pro-
portion of coal. In the case of clayband ironstone calcined on the open hearth the
proportions found convenient in practise are one hutch of the fine ore or oxide for
every six hutches of the ironstone. In the case of clayband ironstone calcined in
running kilns there should be one hutch of the fine ore or oxide for every twenty
of the ironstone. In the case of blackband and ironstone calcined on the open
hearth there may be one hutch of the fine ore or oxide for every three or four of
the ironstone. In most cases the proportion of coal to the total iron should be
increased to an extent that is easily ascertained on trial. The mixing may be
sufficiently effected by scattering the fine ore or oxide over the ironstone with
spades or shovels, the contents of the hutches being deposited in regular order,
according to the proportions adopted.
During the calcination of the heap the finely divided ore or oxide being raised to
a high temperature becomes, agglutinated and formed into lumps suitable for
charging along with the calcined ironstone into the smelting furnace.
By the described process the purple ore or similar oxide becomes freed from the
large per-centage of water usually adhering to it, and much of the sulphur, arsenic,
and copper associated with it is volatilised, so that the quality of the iron obtained
is improved.
Having thus particularly described my said Invention, and the manner of per-
forming the same, I have to state that I do not restrict myself to the precise details
herein-before described, but that what I believe to be novel and original, and claim
as the Invention secured to me by the herein-before in part recited Letters Patent
“is, the utilising of "purple ore" and other similar ores or residuary oxides of iron,

page_text: by mixing them with black band or clayband, or other ironstone, and by calcining
the mixture, substantially as and for the purposes herein-before described.
In witness whereof, I, the said Robert Main, have hereunto set my hand
and seal, this First day of August, in the year of our Lord One thousand
aight hundred and seventy-seven.
Witness,
EDMUND HUNT,
Patont Agent,
Glasgow.
ROBERT MAIN. (L.S.)