A NEW OR IMPROVED PROCESS FOR PREPARING THE MATERIALS FOR MANUFACTURING BASIC FIREPROOF BRICKS AND OTHER BASIC ARTICLES."
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by Henri Adrien Bonneville at the Office
of the Commissioners of Patents on the 16th February 1880. A communi-
cation by Emil André, of Coblence, in the Empire of Germany, Engineer.
HENRI ADRIEN BONNEVILLE, of the British and Foreign Patent Offices, 18, Rue
de la Chaussée d'Antin, Paris, France, and 5, Piccadilly, in the County of Middlesex,
Patent Agent. A NEW OR IMPROVED PROCESS FOR PREPARING THE MATERIALS
FOR MANUFACTURING BASIC FIREPROOF BRICKS AND OTHER BASIC ARTICLES."
A communication by Emil André, of Coblence, in the Empire of Germany,
Engineer.
This Invention relates to a new or improved process for preparing the materials
for manufacturing basic fireproof bricks and other basic articles, by means of gypsum
or freshly prepared sulphate of lime used as cement. This cement, which forms the
base of the new process, is prepared by slacking the burnt lime as usual, and by
adding at the moment of the greatest heat about one half (by weight) of concentrated
sulphuric acid. The resulting product, sulphate of lime, if used in statu nascente,
that is to say, immediately after the first violent effervescence, posesses highly
plastic and cementing qualities, a small quantity, viz., 2% by weight is sufficient
for rendering meager materials highly plastic and tenacious. This artificial sulphato
of lime could be replaced by gypsum, but the first is more preferable. By means of
this mixture and an entirely new process basic fireproof bricks and other basic fire-
proof articles are manufactured.
Either raw lime or dolomite, or magnesian limestone, which contains about 8% of
silica, alumina, and peroxide of iron, is burnt in a pit furnace or reverberatory
furnace at white heat, so as to slag the materials as completely as possible; or the
raw materials being too pure to be slagged, 8-12-16% of silica, alumina, and
peroxide of iron, or one of these elements are added before burning; afterwards the
whole is made into small bricks of spheroidal or rectangular form, which are manu-
factured as fireproof bricks usually are, and burnt in a pit-furnace or reverberatory
furnace by gas or direct flame, also by white heat, so as to be slagged. The burnt
materials when at a red heat are withdrawn from the furnace and besprinkled with
a little water, so as to separate the slagged from the unslagged materials.
having stamped and ground the slagged materials, and added the above mentioned
and described mixture (of sulphate of lime), the basic mass is, like other fireproof
articles, by kneading and press-working or stamping, transformed into all required
forins (bricks, pipes converter bottoms, plugs, stamping-mass) generally for all
objects that ought not to shrink, now being fit for use without repeated burning.
After

page_text: The unslagged materials are manufactured by means of the same mixture and
method for bricks or stamping-mass, their quality being about equal to the firstly
named products, if they are used some weeks after being manufactured, and kept
dry and warm till that time; for all such articles white heat is not required, but
only such heat as to separate the carbonic acid.
For all articles which are liable to shrink by heat, a basic paste may be prepared
with raw limestone or magnesian limestone in mixture with sulphate of lime, with
or without addition of 1-2% of fluorspar, and these articles may be used for
metallurgical, chemical, or architectural purposes, posessing the property of growing
harder by exposure to a humid atmosphere.
Basic fireproof bricks and other basic fireproof articles, prepared according to the
above described process, are used for the lining of furnaces of every kind and shape
of converters, shanks, generally for all metallurgical constructions, especially where
the elimination of phosphorous, silicon, or sulphur in the manufacture of iron and
steel is required.
The difference between this process and that of Thomas Gilchrist, for the manu-
facture of of basic bricks, is very distinct; in the other process bricks are formed of
raw dolomite or magnesian limestone, and are burnt at a white heat; these bricks
shrink very much in burning, are irregular, and often slag together in large irregular
lumps, and often only 10% of a burning being normal, whilst there is a waste and
loss of broken bricks to the extent of 90°-
In consequence, the bricks of Thomas Gilchrist's process are very dear, and the
whole dephosphorization is too expensive. By persuing another method my
Invention gives far superior results, both as to quality as well as to cheapness of
the products. The use and application of freshly prepared sulphate of lime or
gypsum for the manufacture of basic fireproof bricks and other basic fireproof
articles is entirely new, and is the only method whereby articles of every size and
shape can be made.