IMPROVEMENTS IN THE MANUFACTURE OF CEMENT to be as follows:-
Year: 1885

page_text: I WILLIAM JOY of Stonebridge Hill Northfleet in the County of Kent Cement
Burner do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
THE MANUFACTURE OF CEMENT to be as follows:-
"
My invention relates to the process of manufacturing cement by subjecting slurry
in a wet state to the action of heat in a kiln and my said Invention consists of the
improvements hereinafter described in the method of charging the kiln with the
wet slurry by which improvements the thorough and uniform burning of the charge
is ensured.
According to my said invention I partly charge the kiln either in the usual way
or in any other suitable way and ignite the charge and when the charge is well
alight and the flames from the burning fuel are rising freely from the charge
I throw thereon wet slurry mixed with small coal or coke breeze or other suitable
fuel depositing the wet mixture on those parts where the flames are issuing most
freely. The free passage of the hot gases through the charge at the parts where
the wet mixture is lodged is thereby checked and the draught through other parts
of the charge is consequently increased. When by the increased draught at such
other parts the fuel at those parts is caused to burn freely I deposit on thei
further quantities of the wet mixture and thus force the flame and hot gases from
the fuel to find vent at other parts of the charge and so on until the moisture
from those portions of the wet mixture first deposited on the charge as herein
before described has been driven off by the heat and the fuel in the said mixture
is burning and flame is issuing freely from the said portions when I deposit thereon
a further quantity of the wet mixture. In this way I continue feeding the kiln
until fully charged taking care that the draught through the charge shall not at
any time be entirely stopped but only deadened or partly closed at the parts where
the draught is greatest and the flames are issuing most freely.
When the kiln bas in this way been fully charged I allow it to burn out and
draw it in the ordinary manner. Or I draw the burnt clinker from the lower part
before the upper part of the charge is burnt out and continue charging further
quantities of the wet mixture at the upper part and thus work the kiln
continuously.
Instead of feeding the kiln with a mixture of wet slurry and fuel it may be fed
with wet slurry alone until a layer of sufficient thickness has been deposited then

page_text: with fuel and then again with wet slurry until another layer of sufficient thickness
has been deposited and so on.
The kiln may be charged at starting with wet slurry and fuel in alternate layers
or with alternate layers of a mixture of fuel and wet slurry and of fuel with tubes
or flues or passages arranged or formed in the charge as described in the provisional
specification filed by me on the 12th June 1885 in application for Letters Patent
N° 7189.
By the process herein before described the thorough exposure of every part of
the charge to the maximum amount of heat is ensured the charge when drawn
being free from masses burned on the outside and only partly burned or raw inside
which are frequently found in drawing the charge from a cement kiln fed or
loaded in the ordinary way.
W. T. WHITEMAN,
Agent for the Applicant. 15
Improvements in the Manufacture of Cement.
I WILLIAM JOY of Stonebridge Hill Northfleet in the County of Kent Cement
Burner do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
THE MANUFACTURE OF CEMENT" 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 the process of manufacturing cement (such as Portland
Cement) by subjecting slurry in a wet state to the action of heat in a kiln and my
said Invention consists of the improvements hereinafter described in the method of
charging the kiln with the wet slurry by which improvements the thorough and
uniform burning of the charge is ensured.
According to my said Invention I partly charge the kiln either in the usual way
or in any other suitable way and iguite the charge and when the charge is well
alight and the flames from the burning fuel are rising freely from the charge
I throw thereon wet slurry mixed with small coal or with coke breeze or with
small coal and coke breeze mixed together in about equal proportions by bulk or
with other suitable fuel depositing the wet mixture on those parts where the flames
are issuing most freely. The free passage of the hot gases through the charge at
the parts where the wet mixture is lodged is thereby checked and the draught
through other parts of the charge is consequently increased. When by the
increased draught at such other parts the fuel at those parts is caused to burn
freely I deposit on them further quantities of the wet mixture and thus force the
flame and hot gases from the fuel to find vent at other parts of the charge and so

page_text: on until the moisture from those portions of the wet mixture first deposited on the
charge as herein before described has been driven off by the heat and the fuel in
the said mixture is burning and flame is issuing freely from the said portions when
I deposit thereon further quantities of the wet mixture. In this way I continue
feeding the kiln as the burning proceeds until the kiln is fully charged taking care
that the draught through the charge shall not at any time be entirely stopped but
only deadened or partly closed at the parts where before depositing the mixture
the draught is greatest and the flames are issuing most freely.
When the kiln has in this way been fully charged I allow the charge to burn
out and draw it in the ordinary manner. Or when the charge in the kiln has
been so far burned that the clinker in the lower part has become cool I begin to
draw the cool clinker from the lower part before the upper part of the charge is
burnt out and continue charging further quantities of the wet mixture at the
upper part as hereinbefore described and thus work the kiln continuously.
In case at any time the draught appears to be too much checked at any part by
the wet mixture I pass an iron rod down through the dried or partially dried
slurry at the parts where the draught is checked and thus form passages through
the dried or partially dried slurry at those parts through which passages the hot
gases pass from the burning charge below and ignite the fuel in and burn the
slurry at the said parts. I obtain access to the kiln for this purpose by means of
the ordinary aperture at or near the upper part of the kiln which aperture is
ordinarily termed the "loading eye" and I feed the kiln with the wet mixture by
shovelling it through the said aperture or I pass the wet mixture into the kiln in
any other suitable way or by means of any suitable instrument or apparatus.
Any ordinary cement kiln may be used I however find it advantageous to use a
kiln as wide at the bottom as at the upper part and having a large fire bar surface
and in building kilns specially for working according to my process I prefer so to
form them.
Instead of feeding the kiln with a mixture of wet slurry and fuel it may be fed
with wet slurry alone until a layer of sufficient thickness (say about two or three
inches) has been deposited then with fuel and then again with wet slurry until
another layer of sufficient thickness has been deposited and so on but I prefer to
feed the kiln with the mixture of slurry and fuel as the clinker produced from the
mixture of slurry and fuel can be ground with much greater facility than that
produced from slurry alone.
The consistence of the slurry or of the mixture of slurry and fuel must be such
that it will not splash about in the kiln when thrown into it but will remain
where it is thrown. In preparing the mixture of slurry and fuel I take the thick
slurry as it runs from the wash mills used in working according to the process
known as "Goreham's process" or I take the thick slurry from the "Backs" or
settling tanks and I add the fuel to the slurry and thoroughly intermix the two
and thus produce a mixture of convenient consistence. The quantity of fuel
required in working according to my process varies (as in the ordinary process)
according to the weight of the clinker or cement required. The addition of about
from four to five parts by bulk of fuel to eight parts by bulk of slurry is sufficient
to produce a cement of average weight.
The materials ordinarily used in the preparation of slurry for the manufacture
of Portland cement are chalk and clay which are ground together with water but
other materials such as lime and clay or lime and slag are sometimes used and
I wish it to be understood that my invention is applicable to the feeding of kilns
with slurry made of any of these mixtures of materials or of any other mixture of
materials which when properly burned and ground produces Portland Cement or
other cement of similar nature and having similar properties.
By the process hereinbefore described the thorough exposure of every part of
the charge to the maximum amount of heat is ensured the charge when drawn
being free from masses burned on the outside and only partly burned or raw
inside which are frequently found in drawing the charge from a cement kiln fed

page_text: or loaded in the ordinary way. Further the whole expense of drying the slurry
previously to charging it into the kiln is avoided and consequently very great
economy in the manufacture of the cement is effected. There is also less wear
and tear of the kilns in working according to the process hereinbefore described
than in working according to the ordinary process.
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
The improvements hereinbefore described in the manufacture of cement which
improvements consist essentially in charging wet slurry or a mixture of wet slurry
and fuel into a cement kiln while the kiln is in action the wet slurry or the
mixture being deposited in successive portions on the burning charge in the kiln as
the burning proceeds and at the parts where for the time being the charge is
burning most freely.