IMPROVEMENTS IN THE MANUFACTURE OF PORTLAND CEMENT
Year: 1884

page_text: I HARRY JOSEPH COOPER of Drinagh in the County of Wexford, Ireland, Cement
Manufacturer do hereby declare the nature of said invention for "IMPROVEMENTS
IN THE MANUFACTURE OF PORTLAND CEMENT" to be as follows:-
may thus
Heretofore in the various modes adopted or proposed for the manufacture of
Portland cement the materials have had to be exposed to bigh heat in special
apparatus or kilns, thus involving considerable expenditure of fuel. Now according
to my invention and for the purpose of manufacturing Portland cement I utilizo
the heat of iron slag while it is in the molten state as it comes from the furnace,
and produce material for Portland cement by mixing and incorporating with tho
said slag, lime chalk, limestone or other suitable calcareous material.
add to tho slag while in a molten condition and as it flows from the iron furnace a
suitable proportion of chalk, limestone or lime in a state of fine powder or moro or
less subdivided and then further thoroughly mixing or incorporating the materials
by passing the mass through rollers, mortar mills or other suitable apparatus and
then if necessary into a furnace where (by an application of heat by the addition
of coal coke or gas as may be advisable), the necessary chemical action may be
completed to form the whole into a true Portland cement clinker. I then cool and
granulate by air or steam blast or by passing the material through the air (or it
may be by dropping into water) forming sand, or I may effect this otherwise as
may be necessary. I then pulverize by any ordinary method.
It must be understood that all iron slags are not suitable for my manufacture,
Such slags which contain large proportion of iron oxides or of sulphur are not
suitable.

page_text: I HARRY JOSEPH COOPER of Drinagh in the County of Wexford, Ireland, Cement
Manufacturer do hereby declare the nature of said invention for "IMPROVEMENTS
IN THE MANUFACTURE OF PORTLAND CEMENT" and in what manner the same is
to be performed to be particularly described and ascertained in and by the
following statement:—
Heretofore in the various modes adopted or proposed for the manufacture of
Portland Cement, the materials have had to be exposed to high heat in special
apparatus or kilns, thus involving considerable expenditure of fuel.
Now according to my invention and for the purpose of manufacturing Portland
cement I utilize the heat of iron slag while it is in the molten state as it comes
from the furnace and produce material for Portland cement by mixing and
incorporating with the said slag lime, chalk, limestone or other suitable calcareous
material.
I may thus add to the slag while in a molten condition and as it flows from the
iron furnace a suitable proportion of chalk, limestone or lime in a state of fine
powder or more or less subdivided. The proportions would be about from 35 parts
to 50 parts of slag to 100 parts of limestone, or a proportionate quantity of lime,
these proportions varying according to the composition of the slag and the amount
of pure carbonate of lime contained in tho limestone or of pure Ca and Ca O in the
lime. I then further thoroughly mix or incorporate the materials by passing the
mass through rollers, mortar mills or other suitable apparatus and then if necessary
into a furnace where (by an application of heat by the addition of coal, coke or
gas, as may be advisable) the necessary chemical action may be completed to form
the whole into a true Portland cement clinker. I do not however find furnacing
necessary when working on a small scale. I then cool and granulate by air or
steam blast or by passing the material through the air forming sand. I then
pulverize by any ordinary method.
It must be understood that all iron slags are not suitable for my manufacture,
Such slags for instance which contain large proportions of iron oxides or of sulphur
are not suitable.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
First. In the manufacturo of Portland cement from slag adding to the slag
while in a molten state coming from the furnace, powdered chalk, limestone
or lime substantially as set forth.

page_text: Second. The manufacture of Portland cement by mixing and incorporating slag
liquid from the furnace with powdered chalk, limestone or lime and granulating
and pulverizing after cooling substantially as set forth.
Third. The manufacture of Portland cement by adding to slag while in a
molten state as it comes from the furnace, powdered chalk, limestone or lime,
then thoroughly mixing in mortar mill or other suitable apparatus and then
furnacing and then granulating and pulverizing after cooling substantially as
set forth.