Year: 1885

page_text: The present invention has for its object a process for the manufacture of lime
cement applicable to the production of cements, mortars and hydraulic concretes,
and artificial stone replacing natural stone.
The process may be considered as consisting of two operations-the preparation
of the materials and the roasting.
The preparation of the material consists in taking calcareous stone in a state
producing ordinary fat lime, which is slaked by plunging into water, and which is
immediately pulverised and passed through a sieve, and also raw clay, which is
dried either in the sun or under sheds by the aid of heat when the climate readers
it necessary-when the clay is thoroughly dry it is crushed and passed through
a sieve.
The two materials thus powdered are mixed in a dry state in proportions which
vary from 7 to 9 volumes of clay to 2 to 4 volumes of lime, and thus they are placed
in a mixer with the gradual addition of the quantity of water necessary to produce
a paste rather softer than is employed for moulding into bricks.
When the mass comes to the consistence for moulding, it is moulded into small
bricks by means of a machine of ordinary construction-these bricks are dried
either in the sun or under sheds with the aid of heat, when the climate renders it
necessary, and when they are thoroughly dry and suitable for crashing they are
reduced by crushers into grains of a size varying from that of a bean to a
small pea.
The materials thus prepared then pass to the second operation, which is that of
roasting.
The grains furnished by the preceding operation are introduced into rotating
cylinders of very stout sheet iron heated by any suitable arrangement; they are
mounted upon horizontal axes and carry radial arms which during the rotating of
the cylinders, keep the matter which they contain in a state of continual agitation
so as to insure regularity in the roasting.
The roasting is carried on with a moderate fire for the first two or three hours
and hastened towards the end of the operation which extends over ten to eighteen

page_text: hours according to the quality of the lime cement which it is desired to obtain-
the continuance of the roasting increases the rapidity with which the cement sets
and its hydraulic property.
As soon as the roasting is terminated the fire is withdrawn and the material is
allowed to cool in the cylinder which is caused to rotate continuously until
completely cold.
When the material is cooled down it is taken out of the cylinders and crushed
and so reduced into an absolutely impalpable powder, then to this powder fat lime
slaked by immersion and finely pulverised is again added. This new mixture is
made in proportions varying from 1 to 3 volumes of fat lime to one volume of
roasted material.
The lime cement thus obtained can be packed in hermetically closed barrels and
will keep in this way for several years.
The roasted material may also be packed in this manner and the second addition
of fat lime made only when the lime cement is to be employed.
The lime cement obtained by the above described process advantageously
replaces Portland and other cement.
By adding to it from 1 to 3 parts of suitable sand an excellent hydraulic mortar
is obtained; by adding broken stone and pebbles a hydraulic concrete is made of
superior quality and at a low price.
Finally, this lime cement is particularly suitable for the manufacture of artificial
stone.
C
Dated this 27th dox of October 188K
CARPMAEL & Co.,
Agents for the Applicant.

page_text: It
This process is based upon the employment of fat lime with which it has been
in vain attempted up to the present time to manufacture hydraulic cements.
consists in a special mode of adding the clay necessary for the production of cement
and the burning of these matters as hereinafter explained.
This process enables cements to be obtained which set either slowly or rapidly as
required and which acquire in a longer or shorter time a hardness superior to that of
the corresponding rapidly setting cements alone known up to the present time, and
this either in water or in air consequently an ordinary mason can employ this
material without any special skill and with a certainty of success.
The process may be considered as consisting of two operations-the preparation
of the materials and the roasting.
The preparation of the material consists in taking calcareous stone producing
ordinary fat lime, which is slaked by plunging into water, and which is
immediately pulverized and passed through a sieve; and also raw clay, which is
dried either in the sun or under sheds by the aid of heat when the climate renders
it necessary.
When the clay is thoroughly dry it is crushed and passed through
a Bieve.
The two materials thus powdered are mixed in a dry state in proportions which
vary from 7 to 9 volumes of clay to 2 to 4 volumes of lime, and thus they are
placed in a mixer with the gradual addition of the quantity of water necessary to
produce a paste rather softer than is employed for moulding into bricks. This soft
consistence is given to the materials with the intention to allow them the better to
re-act the one on the other When the mass comes to the consistence for moulding,
it is moulded into small bricks by means of a machine of ordinary construction.
These bricks are dried either in the sun or under sheds with the aid of heat, when
the climate renders it necessary, and when they are thoroughly dry and suitable
for crushing they are reduced by crushers into grains of a size varying from
that of a bean to a small pea.
The materials thus prepared then pass to the second operation, which is that of
roasting.
The grains furnished by the preceding operation are introduced into rotating
cylinders of very stout sheet iron heated by any suitable arrangement; they are
mounted upon horizontal axes and carry radial arms which, during the rotating of
the cylinders, keep the matter which they contain in a state of continual agitation
so as to insure regularity in the roasting. This arrangement of rotating cylinders
does not require to be further described, being well known.
The roasting is carried on with a moderate fire for the first two or three hours
and hastened towards the end of the operation which extends over ten to eighteen
hours according to the quality of the lime cement which it is desired to obtain.
The longer continuance of the roasting increases the rapidity with which the
cement sets and its hydraulic property.
As soon as the roasting is terminated the fire is withdrawn and the material
is allowed to cool in the cylinder which is caused to rotate continuously until
completely cold.
When the material is cooled down it is taken out of the cylinders and crushed
and so reduced into an absolutely impalpable powder, then to this powder fat lime
slaked by immersion and finely pulverised again added. This new mixture is
made in proportions varying from 1 to 3 volumes of fat lime to one volume of
roasted material according to the energy which it is desired to give to the lime
cement, both in setting and in hardening. The greater the quantity of lime added
the less hard is the product and the slower is the setting, but the cement does not
cease to be a hydraulic and it is more economical.
The lime cement thus obtained can be packed in hermetically closed barrels
and it will keep in this way for several years. It will bear a sea voyage without
risk of change of any sort, provided that the barrels are protected from air and
moisture.

page_text: The roasted material may also be packed in. this manner and the second addition
of fat lime made only when the lime cement is to be employed.
IN
The lime cement obtained by the above described process combines the three
fundamental properties-Resistance to crushing-adhesion and impermeability.
It advantageously replaces Portland and other cement in the construction of the
arches of bridges, aqueducts, sewers, cisterns, moist chambers, vaults, and all
submarine and subaqueous works.
By adding to it from 1 to 3 parts of suitable sand an excellent hydraulic mortar
is obtained. By adding broken stone and pebbles a hydraulic concrete is made of
superior quality and at a low price.
Finally, this lime cement is particularly suitable for the manufacture of artificial
stones of different qualities, which are very economical and replace natural stones.
It is possible by coloring the materials to obtain in this manner stones of the
most varied shades of colour.
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. The process by which fat lime is rendered hydraulic substantially as described,
consisting of two operations, in the first of which the fat lime slaked by immersion
is reduced to powder and mixed with dry clay also pulverised, then the whole
made into paste, dried, and granulated; and in the second operation the granular
matter so obtained is roasted in revolving cylinders, then crushed to impalpable
powder and fat lime slaked by immersion and reduced to impalpable powder is
added to it; the product constituting an inexpensive hydraulic lime cement of low.
price and of qualities in respect to setting and resistance superior to those of
hydraulic cements at present known.
2. The process of roasting the mixture of fat lime and clay in revolving
cylinders.
3. The manufacture substantially as above described by means of fat lime of
hydraulic cements or agents which can be made to set rapidly or slowly as required
and which are applicable to constructive works either under water or exposed to
the air.
4. The production by means of my lime cement of artificial stones of all
colours and qualities to replace natural stones for building purposes.
Dated this 26th day of July 1886-