IMPROVEMENTS IN THE MANUFACTURE OF CEMENT
Year: 1885

page_text: I ROBERT STONE, of 101 Leadenhall Street, in the City of London, Engineer,
do hereby declare the nature of my Invention for "IMPROVEMENTS IN THE
MANUFACTURE OF CEMENT," to be as follows:-
Instead of mixing ordinary fuel, such as coal, coke or breeze, with the web
slurry, I mix vitriol or oil of vitriol and petroleum or petroleum spirit or any
other oils, liquids or chemicals of a highly inflammable nature, and either mixed
together or used separately. This novel method of mixing the above named oils
or liquids or any other liquids or chemicals of a highly inflammable nature, direct
with the slurry while in the blending tank or other receptacle, admits of the
slurry being placed directly into the furnaces or kilns, without the admixture of
coke, breeze or coals, as the heat from the combustion of such liquids exceeds the
heat arising from ordinary coals or coke, and has the effect of both drying and
burning the slurry into clinkers by one operation, and a superior class of cement
can be produced thereby than with ordinary fuel, and at much less cost. Also by
saturating the dry slurry with the aforesaid liquids the slurry can be burned to a
high quality of cement, much more so than with ordinary fuel.
In connection with the kilns or furnaces I erect and apply draught shafts, which
can be made of bricks wood or other material. This allows the kilns or furnaces
to be loaded full at once, as the draught shafts have the effect of carrying the heat
from the bottom to the top of the kilns or furnaces; consequently the whole of the
kilns or furnaces are dried and heated uniformly throughout. I sometimes lay a
thick layer of fuel on the bottom of the kilns and pump 4 to 6 feet, more or less,
of slurry with or without the liquid ingredients, and above this layer of slurry
I place a layer of dried slurry, then a layer of fuel, then again a layer of dried
slurry, and so repeat the process; the layers of wet slurry thus separating the fuel
from such layers of wet slurry; and I find by experiment, when the wet slurry is
mixed with the fuel, an inferior soft clinker is produced.
In some instances I burn the chalk and river mud, as raw material, without
washing, either in the foregoing as to liquids and fuel, or in the ordinary way;
he novelty in this instance being the direct application of the raw material, and
he saving of washing, drying and turning thereby effected.
.

page_text: Improvements in the Manufacture of Cement.
I, ROBERT STONE, of 101 Leadenhall Street, in the City of London, Engineer,
do hereby declare the nature of my said invention and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement:-
The object of my invention is to effect improvements in the manufacture of
cement.
Instead of mixing ordinary fuel, such as coal or coke, with the wet slurry; I mix
therewith vitriol or oil of vitriol, and petroleum or petroleum spirit, or any other
oils, liquids or chemical substances of a highly inflaminable nature, and either
mixed together or used separately.
By this novel method of mixing- the above named oils, liquids or chemicals,
directly with the wet slurry, while in the blending tank or other receptacle, I am
enabled to place the slurry directly into the furnaces or kilns without the usual
admixture of coke, or coals; as the heat arising from the combustion of such
liquids exceeds that arising from ordinary coals or coke, and has the effect of both
drying and burning the slurry into clinkers by one operation, and a superior class
of cement is produced thereby compared to that produced with ordinary fuel, and
at much less cost.
In order to secure the necessary supply of air to support combustion, I erect or
build, in the kilns or furnaces, temporary draught shafts or air channels, as shewn
in plan in the accompanying drawing, in which a a is the wall of the kiln, and
bb are the temporary draught shafts, which are made as numerous as required.
These shafts are usually made of boards, which carry the air upwards, and last
until the slurry is well fired, when the shafts burn away, and the air afterwards
gains access to the burning mass in the ordinary way. The shafts may, however,
be made of other suitable materials.
Another method of securing temporary draught in the kilns consists in the
placing of peat, brushwood, saw dust, jute, tow, rope, or other material, fibrous or
otherwise, which may be consumed when the heat has increased.
I sometimes arrange the loading of the kilns in the following manner:-
First, a layer of fuel composed of coke or coals, is laid upon the bottom of the
kiln next from four to six feet, or thereabouts, of slurry, with or without the
aforesaid inflammable liquids above this a layer of dried slurry: then again a
layer of fuel composed of coke or coals, as before; and so repeat the layers until
the kiln is filled up.
The above arrangement of strata is superior to that of mixing the wet slurry
with ordinary fuel, which latter process produces an inferior soft clinker.
In some cases I burn the chalk or limestone and river mud, or the chalk alone,
as raw material, without washing, either in the manner above described as to
liquids and fuel, or in the ordinary way; the novelty in this instance being the
direct application of the raw material, and the saving of washing drying and
burning thereby effected.

page_text: To prevent the liquid fuel burning away too rapidly I sometimes find it
advantageous to mix therewith tar or other material of a slower burning character
whereby the time occupied in the process may be suitably increased.
I also sometimes mix flints or iron slag or other silicious substances or silicates
when burning the chalk or limestone without washing I also sometimes burn and
grind the silicates separately, and mix the same with the burnt lime or chalk
when ground or while grinding.
In some cases I mix the inflammable liquids, before mentioned, with the coke or
coals, used in connection with the aforesaid processes.
In connection with the processes and operations above described, I make use of
the machinery described in my Final Specification filed in pursuance of an
application for Letters Patent dated 15th September 1885, No 10,934.
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:-
1. In the manufacture of cement from slurry or chalk or limestone the
application and use of vitriol and liquid fuel, substantially as herein before
described.
2. The method & means of forming artificial and temporary shafts and air ducts
or channels for admitting air to the slurry while raising the heat substantially as
hereinbefore described, and partly shewn on the drawing.
3. The method of arranging alternate layers of fuel, wet slurry, and dry slurry
in succession, with or without liquid fuel, substantially as herein before described.
4. The method of burning chalk and river mud substantially as herein before
described.
5. The general arrangements and combinations of the several and respective
parts and processes, together forming my improvements in the manufacture of
cement substantially as herein before described and shewn on the drawing.
GEO. DOWNING,
Agent for Applicant.