Improvement in the Manufacture of Portland Cement.
Year: 1899

page_text: . Date of Application, 19th Apr., 1899
Complete Specification Left, 22nd Dec., 1899-Accepted, 17th Mar., 1900
PROVISIONAL SPECIFICATION.
Improvement in the Manufacture of Portland Cement.
WILLIAM ERNEST HOPPS, Cement Manufacturer's Clerk, The Cobden Hotel,
Charles Street, Hull, do hereby declare the nature of this invention to be as
follows: :―
The improvement consists in taking in the proportions given, pure chalk, dried
and ground to an impalpable powder by passing through a fine grinding mill;-
113 lbs.; a pure silica such as clean sand, flints, or a sandy clay or mud, dried
and ground to an impalpable powder;-35 lbs.; and carbonate of soda ground
to a fine powder; 5 lbs. This combination is thoroughly mixed in a
mixing machine, and passed through a brick-making machine. The bricks are
then burned in a kiln at white heat until all the carbonic acid gas is driven off.
The resulting clinker is then passed through crushing and fine grinding mills.
Dated this 18th day of April 1899.
Improvement in the Manufacture of Portland Cement.
I, WILLIAM ERNEST HOPPS, of 20, Grange Avenue, Falsgrave, Scarborough,
Manager, late of "The Cobden Hotel," Charles Street, Hull, 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:-
The improvement consists in taking in the proportions given below, a pure
chaik dried and ground to an impalpable powder by passing through a fine
grinding mill--123 pounds, a pure silica such as clean sand, flints, or a very sandy
clay or mud, ground to an impalpable powder-26 pounds carbonate of soda ground
to a fine powder-5 pounds sulphate of lime (gypsum) ground to a fine powder-
4 pounds. Should the chalk, sand, flints, or sandy clay or mud contain any
percentage of soda or gypsum, such percentage to be deducted from the quantities
of soda or gypsum, proposed to be added. The combination of ingredients is then
thoroughly mixed in a mixing machine and passed through a brickmaking
machine. The bricks are then burnt in a kiln until all the carbonic acid gas is
driven off and the chemical changes by calcination are completed. The resulting
clinker is passed through crushing and fine grinding mills.
The best method of preparation is to first dry the chalk and then pass it through
a fine grinding mill, using the resulting impalpable powder in the proportion of
123 pounds, (if made from a pure chalk). The silica, in the shape of clean
siliceous sand, slightly roasted flints, or a sandy clay or mud, should be first
D .

page_text: dried and then passed through a fine grinding mill, to reduce to an impalpable
powder and be used in the proportion of 26 pounds to 123 pounds of chalk
powder. The carbonate of soda to be ground to a fine powder and used in the
proportion of 5 pounds to 26 pounds of silica powder and 123 pounds of chalk
powder. The sulphate of lime (gypsum) to be ground to a fine powder and used
in the proportion of 4 pounds to 5 pounds of soda powder, 26 pounds of silica
powder and 123 pounds of chalk powder. Should the chalk, sand,
flints, or sandy clay or mud contain
soda
any percentage of
gypsum such percentage to be deducted from the quantities of soda or gypsum
proposed to be added. The composition is then thoroughly mixed in a mixing
machine, passed through a brickmaking machine and the bricks are burnt in a
kiln until all the carbonic acid gas is driven off and the chemical changes by
calcination are completed.
or
The clinker is broken up by a crushing mill and subsequently passed through a
fine grinding mill.
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―
That the constituent materials named, manufactured in the manner described,
will result in a harder setting and more durable cement than at present manu-
factured, also that the manufacturer will have a greater control over the chemical
proportions of the constituent ingredients than he has with chalk and clay.
The novelty of the invention consists in manufacturing the Portland cement
from chalk and sand, flints, sandy clay or mud, soda and gypsum, in the manner
described herein as compared with manufacturing Portland cement from chalk
and clay.