Improvements in the Manufacture of Cement.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Cement.
A communication by The Firm of TERRANOVA INDUSTRIE, C. A. KAPFERER AND
SCHLEUNING, of 27, Briennerstrasse, Munich, in the Empire of Germany,
Manufacturers.
1, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Manchester,
both in the County of Lancaster, 118, New Street, Birmingham, in the County
of Warwick, and 322, High Holborn, in the County of Middlesex, Civil Engineer,
do hereby declare the nature of this invention to be as follows:-
This invention has for its object the manufacture of a cement which by
avoiding the ordinary dull grey colour is especially suitable for decorative pur-
poses, artificial stones and the like.
For this object a clay which is free from iron (kaolin, pipe clay and the like)
is mixed with feldspar (orthoclase) which is also as free as possible from iron,
and by the present invention this mixture takes the place also quantitatively
of the usual argillaceous constituents in the manufacture of Portland cement.
The other constituent is, as in that case, lime, which must of course also be as
free from iron as possible.
Attempts have already been made to obtain a similar final result by the
selection of clays and lime, both free from iron. The clinkering basis of such
mixtures is however so high that by reason thereof industrially valuable results
are excluded, and also the unavoidably high alumina contents allowed of no
satisfactory product being obtained even after the clinkering.
The results also which Fahnejelm, Ransome and others obtained correspond
with this (see Feichtinger 1884, p. 192) as the therein described composition
and treatment show that these inventors could not have burnt the substances up
to clinkering.
The mixture of kaolin and feldspar hereinbefore mentioned may be regulated
in such a way that the high fusing temperature caused by the absence of iron
compounds and alkalies and also the too high alumina contents caused by the
introduction of the kaolin are reduced, and may be confined to the conditions
proved to yield the best cement. The mixture is further treated with the
necessary amount of lime in the manner usual in cement-making, and yields
when burnt to fusing point, i.e. beyond the clinkering limit, a product which
hardens equal to the best cement.
If it.be burnt only to ordinary clinkering the result is a material very similar
to Roman cement but quite clear like the before mentioned one.
It is evident that theoretically similar proportions between non ferruginous,
silicious compounds of clay and lime may also be obtained in other ways.
A similar result to that herein before described may be obtained for instance
by mixing kaolin, soluble silicic anhydride (infusorial earth, waste silica) and
alkali. What Ransome burnt with similar materials does not affect this inven-

page_text: tion, as he does not form clinkers and also would attain nothing thereby in
view of his proportionate amounts.
In experimenting with the present invention and in fact at the commencement
of such experiments, the foundation material for a cement approaching extremely
closely the objects was obtained by making an easily fusing mixture of kaolin,
pure quartz sand or quartz powder and lime either with or without another
material than that mentioned which fluxes in lime (alkali, fluorspar, feldspar or
the like), to which it was only necessary in order to obtain a mixture analogous
to that herein before mentioned, to add the further amount of lime necessary,
and to mix the whole as raw material, and to burn out therefrom in the ordinary
manner the cement clinkers. The product actually exceeded what is herein-
before described and only calculation induced in the present case the modified
and cheaper procedure to be adopted.
The last indicated method may also be utilized by the first burnt fused
material being granulated ground and used as puzzolana.
Dated this 2nd day of September 1899.
A communication by The Firm of TERRANOVA INDUSTRIE, C. A. KAPFERER AND
SCHLEUNING, of 27, Briennerstrasse, Munich, in the Empire of Germany,
Manufacturers.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Manchester,
both in the County of Lancaster, 118, New Street, Birmingham, in the County
of Warwick, and 322, High Holborn, in the County of Middlesex, Civil Engineer,
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:-
This invention has for its object the manufacture of a cement which by
avoiding the ordinary dull grey colour is especially suitable for decorative pur-
poses, artificial stones and the like.
For this object a clay which is free from iron (kaolin, pipe clay, and the like)
is mixed with feldspar (orthoclase) which is also as free as possible from iron,
and by the present invention this mixture takes place also in the proportion of
4 parts of kaolin to 6 parts of orthoclase. To these are added lime, which must
of course also be as free from iron as possible.
A normal kaolin contains 47% SiO2, 39% ALO, & 14% H2O. A normal
feldspar 68 68% SiO2, 19-48% A₁₂O, & 11.84% NaO. If these substances be
mixed in the said proportion of 4'6 a material is obtained of the following com-
position 60008% SiO2, 27-288% A₁₂O, 7.104% Na₂O, 56% H₂O.
Attempts have already been made to obtain a similar final result by the selection
of, clays and lime, both free from iron. The clinkering basis of such mixtures is
however so high that by reason thereof industrially valuable results are ex-
cluded, and also the unavoidably high alumina contents allowed of no satis-
factory product being obtained even after the clinkering.
The results also which Fahnejelm, Ransome and others obtained correspond
with this (see Feichtinger 1884, p. 192) as the therein described composition

page_text: and treatment show that these inventors could not have burnt the substances up
to clinkering.
The mixture of kaolin and feldspar hereinbefore mentioned may be regulated
in such a way that the high fusing temperature caused by the absence of iron
compounds and alkalies, and also the too high alumina contents caused by the
introduction of the kaolin are reduced, and may be confined to the conditions
proved to yield the best cement. The mixture is further treated with the
necessary amount of lime in the manner usual in cement-making, and yields
when burnt to fusing point, i.e. beyond the clinkering limit, a product which
hardens equal to the best cement.
If the lime added be carbonate of lime a powder of the following constituency
is obtained 15'002% SiO2, 6822 AL0, 1776%, Na₂O, 14% H2O, 75% CaCO
yielding a cement of the following constitution 22·868% Si0, 104% ALO,
2707%, Na,0, 64'025% CaO.
If it be burnt only to ordinary clinkering the result is a material very similar
to Roman cement but having a clear colour like the before mentioned one.
It is evident that theoretically similar proportions between non ferruginous,
silicious compounds of clay and lime may also be obtained in other ways.
A similar result to that herein before described may be obtained for instance
by mixing kaolin, soluble silicic anhydride (infusorial earth, waste silica) and
an alkali preferably carbonate of soda. What Ransome burnt with similar
materials does not affect this invention, as he does not form clinkers and also
would attain nothing thereby in view of his proportionate amounts.
In experimenting with the present invention and in fact at the commencement
of such experiments, the foundation material for a cement approaching extremely
closely the objects was obtained by making an easily fusing mixture of kaolin,
pure quartz sand or quartz powder and lime either with or without another
material than that mentioned which fluxes in lime (carbonate of soda, fluorspar,
feldspar or the like), to which it was only necessary in order to obtain a mixture
analogous to that hereinbefore mentioned, to add the further amount of lime
necessary, and to mix the whole as raw material, and to burn out therefrom in
the ordinary manner the cement clinkers. The product actually exceeded what
is hereinbefore described and only calculation induced in the present case the
modified and cheaper procedure to be adopted.
The last indicated method may also be utilized by the first burnt fused
material being granulated ground and used as puzzolana.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, as communicated to
me by my foreign correspondents, I declare that what I claim is;-
1. In the manufacture of hydraulic aluminous cement the avoidance of
ferruginous compounds by using feldspar both as a flux and for correcting the
disturbances of the proportions between silicic acid and clay, arising from the
use of clay free from iron, substantially as herein before set forth.
2. The direct use of feldspar instead of clay in cement substantially as de-
scribed.
3. A flux as a silicious basic or foundation material for a cement or even for
direct use as puzzolana, consisting of clay free from iron and amorphous or
crystallised silicic acid with an addition of lime always calculated to allow of
easy fusibility and with or without other known fluxes (alkali, fluor spar, or
feldspar) substantially as described.
Dated this 30th day of March 1900
WM. P. THOMPSON & Co.,
Agents.