Improvements in the Manufacture of Cement.
Year: 1899

page_text: Date of Application, 20th June, 1899-Accepted, 14th Oct., 1899
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Cement.
I, WILHELM BORGOLTE, Senior, of 8, Altmarktstrasse, Höxter, in the German
Empire, Master Builder, 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 relates to a process for the manufacture of a novel kind of
cement which, as compared with Portland cement, not only possesses the advantage
that it offers considerably more resistance to the action of atmospheric carbonic
acid gas and dampness, but that it also, on setting, forms a hard shiny or polished
mass. The product obtained by the process hereinafter described when mixed
with water, adheres with great strength and possesses considerable resistance to
the action of dilute acids. For building purposes the new cement is of special
importance as it has the most valuable property of durably taking, when freshly
set and without any special preparation, oil colours and other similar coatings.
According to the invention the process consists in separately burning, in the
absence of air, the raw materials usually employed in cement manufacture, the
said materials being, before they are manufactured into cement raw mixture,
mixed with a hydrocarbon which is with difficulty decomposed, such as tar naphtha,
paraffin or with materials yielding hydrocarbons such as coal, sawdust, fat. The
materials so treated have a black or dark grey appearance as graphite is formed
by the heating in the absence of air, the said graphite being deposited on the
surface and in the pores of the materials. After the pulverisation of the products
obtained by the burning in the presence of the hydrocarbon they are again burnt
whilst mixed in the requisite proportions with addition of oil and coal, the opera-
tion taking place without the access of air, that is to say, in an atmosphere of
hydrocarbons.
In carrying out the process the raw materials to be burnt are separately ground
to a powder and mixed with about 02 parts by weight of a hydrocarbon which
is with difficulty decomposed, such as tar, oil, paraffin, etc., Water is added to
the mixture in such quantity that a plastic mass is formed from which bricks
can be made which, after drying, are burnt without the access of air. For
example, the following proportions may be employed, that is to say,-
100 parts by weight of ground limestone to 0'2 parts by weight of tar or
paraffin,
100 parts by weight of ground clay to 0'2 parts by weight of tar or paraffin, etc.
The products obtained are broken up, ground and mixed together in the neces-
sary proportions, and then after the addition of the hydro-carbon materials, burnt
without the access of air.
Experiments with raw materials at hand have shewn that the following mixture

page_text: of materials Durnt and ground in the above
VILC
of hydrocarbon and without the access of air give a good glazed cement.
2 parts by weight of limestone.
1 part
1
"
"
"
"
39
995
."
"
"
"
"
1
"
"
"
"
clay.
clay-marl.
alumina.
ground coal.
To the intimate mixture of the above ingredients in the proportions named I
add 2% of a hydrocarbon, such as tar, paraffin, etc., the mixture being then moulded
with the addition of water, dried and burnt without the access of air. The product
obtained is then broken pulverized and ground similarly to Portland cement.
When other raw materials are employed the raw mixture will be varied as
required.
The glazed cement so obtained possesses a high binding power and when the
duty required of it is light it can be mixed, according to the use to which it is 1
to be put, with unburnt minerals or with burnt minerals and hydrocarbon. I
have found that the following proportions of materials for casting and stamping
cements give good results naniely,-
2 parts of glazed cement.
2
"
"
1 part
1
دو
2
39°
1
"'
2 parts
.39
2.
"
"
raw ground clay.
ground burnt clay-marl
ground sandstone."
ground burnt slaty marl.
ground burnt red sandstone, and
ground.cinder.
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
1 claim is-
1. A process for the manufacture of cement which sets. hard, has a polished or
glazed appearance and withstands the action of the weather, the said process
consisting in burning the raw materials. usually employed in the manufacture of
Portland cement separately with hydro-carbon or similar compounds which are
with difficulty decomposed and without the access of air after which the ground
products are broken up and are mixed in suitable proportions and then again
burnt without the access of air with the addition of hydrocarbon materials; sub-
stantially as hereinbefore described.
2. The process of mixing the product obtained by the process described. in
Claim 1 with suitable raw powdered minerals for the purpose of obtaining a cheap,
glazed cement, substantially as described.
3. The process of mixing the product obtained by the process described in
Claim 1 with ground minerals which have previously been burnt with hydrocarbon
materials without the access of air for the purpose of obtaining.a. better, cheap,
glazed cement, substantially as described.
4: Cement manufactured substantially as hereinbefore described.
Dated the 20th day of June 1899
2
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.