Improvements in the Art of Manufacturing Cement.
Year: 1896

page_text: Date of Application, 4th Mar., 1896-Accepted, 18th Apr., 1896
COMPLETE SPECIFICATION.
Improvements in the Art of Manufacturing Cement.
I, ROBERT AUGUSTUS CHESE BROUGH of 24 State Street, New York City, in-
the County and State of New York, United States of America, Manufacturer, 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:-
My invention relates to improvements in the art of manufacturing cement, either
from the artificial mixture of clay or chalk and carbonate of lime, or from the
cement rock.
It has heretofore been common, in manufacturing artificial cement, to mix the
clay or chalk and the carbonate of lime in the proportion of about twenty-four per
cent. of the clay or chalk and seventy-six per cent. of the carbonate of lime; then.
either form the mixture into bricks, burn the bricks in kilns, and finally grind to a.
powder, or feed the mixture into a rotary cylinder, and burn it therein by an oil
jet spray. In manufacturing cement from cement rock, it has been common to
crush the rock, then burn it, intermixed with layers of coke or anthracite coal, in.
kilns, and finally grind the product.
My present invention contemplates the manufacture of cement, either from the-
cement rock, or the mixture of clay and carbonate of lime, by submitting a down-
wardly falling stream of the powdered mixture, or ground rock, to the highly
heated products of combustion from an oil, gas, or coal fire, and subsequently
reducing the burned product to the required degree of fineness.
In carrying my inethod into practice, I feed the ground rock or mixture into the
top or upper portion of a tower lined with fire-brick, fifty feet or more in height,.
and permit it to fall slowly along down the interior of the tower, while directing-
the heated products of combustion upwardly within the tower, in intimate contact
with the mass of falling material, and causing the heated products of combustion
to become intercommingled with the mass, by breaking up the falling mass by.
interior bars or projections; or, in practice, it might be preferable to leave out the
transverse interfering bars, and to so increase the height of the tower, that the-
powdered material, while falling freely of its own gravity, should be exposed long
enough to the heat of the ascending flame, to produce the proper chemical action.
necessary to the formation of cement clinkers.
A structure for carrying my method into practical use is represented in the
accompanying drawings, in which :-
Fig. 1 represents the tower and its accessories in vertical section, and
Fig. 2 represents a cross section of the tower, on the line 2-2 of Fig. 1.
The tower, represented, as a whole, by A, is provided with a substantially-
vertical flue B, through which the material to be burned is allowed to fall, and up.
through which the hot products of combustion are caused to pass, and a second
substantially vertical flue B', separated from the flue B (except where it communi-
cates with the flue B at the top of the. tower) by a partition wall a. The heated.
products of combustion, after passing from the flue B downwardly through the
Hue B', are conducted through a chamber B2 in which there is located a system of
water pipes c, in communication with a drum C, provided with a steam dome c',
whereby the waste heat from the flue B may be utilised to generate the steam for
supplying an oil jet to the interior of the flue B, through a jet pipe D, when oil is

page_text: used as a fuel, and may also furnish the power necessary to feed the material to be
burned, into the top of the tower.
From the chamber B2, the products of combustion are led to an uptake B',
which may be relied upon to furnish the required amount of draught, to force the
flame from the heater up throughout the falling mass of material to be burned.
The interior of the flue B may be provided with numerous cross bars a', arranged
in staggered order, for thoroughly breaking up the falling mass, and permitting the
flame from the heater to permeate, and come into intimate contact with every
portion of the mass.
The material may be conveyed to the top of the tower by an endless chain
conveyor E, of any well-known or approved form, and forced into the flue B by a
plodder F, as the burned material passes through the bottom of the tower, it
may be conveyed away by cars G arranged to pass beneath the mouth of the
outlet a².
The air for supporting the combustion is taken in at the outlet a², and a further
supply of air may be furnished, if necessary, by an opening as in tower (just above
the outlet a²), which can be opened or closed by a hinged shutter.
The interior should be so shaped, that the cross bars should not be more than
three feet six inches long, and at each end they should rest on a long supporting
bar built into the lining. If these bars were longer, their life would be short, and,
by allowing their ends to rest on a long bar on each side, they can readily be
replaced by others. The long supporting bars on each side will, by,áction of the
heat, become attached to, and form a part of, the lining.
The method hereinabove described, has the advantage of saving time and labor,
materially reducing the cost of the plant for a given out-put, and improving the
quality of the cement.
A small quantity of mineral oil mixed with the crushed rock, or with the mixture
of clay or chalk and carhonate of lime, will facilitate the burning, and will not
injure, if it does not improve, the final product.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. Burning the material from which cement is made, by feeding in a pulverised
condition into the top of a vertical tower, and exposing it, while fa g of its own
gravity, to the intimate action of an ascending flame, sufficient in i. at to produce
the chemical action on the material necessary to form cement clinkers, which are
then ground into cement, substantially as set forth.
2. The process of manufacturing cement, consisting in mixing petroleum oil with
the crushed rock or mixture of clay or chalk and carbonate of lime, and the
exposing the mass, while falling of its own gravity, to the intimate action of an
ascending flame, sufficient in heat to produce chemical action in the material
necessary to form cement clinkers, substantially as set forth.
Dated this 4th day of March 1896.
NEWTON & SON,
Agents for the Applicant.