IMPROVEMENTS IN BURNING AND DRYING BRICKS, POTTERY, EARTHENWARE, CLAY, LIME, AND CEMENT, AND IN THE APPARATUS EMPLOYED THEREIN
Year: 1866

page_text: PROVISIONAL SPECIFICATION left by Robert Kunstmann at the Office
of the Commissioners of Patents, with his Petition, on the 7th July
1866.
I, ROBERT KUNSTMANN, of Nuremberg, in the Kingdom of Bavaria,
Engineer, but at present residing at 884, City Road, in the County. of Mid-
dlesex, do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN BURNING AND DRYING BRICKS, POTTERY, EARTHENWARE, CLAY, LIME, AND
CEMENT, AND IN THE APPARATUS EMPLOYED THEREIN," to be as follows:-
This Invention relates to a peculiar construction and arrangement of kilns
for burning in a continuous manner bricks, pottery, earthenware, clay, lime,
cement, and other similar substances, also to a peculiar mode or method of
drying bricks previous to their being burnt, and to the apparatus employed
for that purpose.
The improved kiln consists of two or more chambers communicating with
each other and with a chimney by special flues provided with dampers for
establishing or cutting off the communications as required; each chamber is
heated by means of one or more fire-places situate on one or more sides of
such chamber.
The grate which I propose to use for these fire-places is a stepped grate,
that is to say, a grate composed of a number of parallel bars or shelves
disposed above one another in the form of steps, the whole forming a stepped
or inclined fuel surface through which the air bas a free passage between the
several bars. The exterior of each grate is closed to the atmosphere by

page_text: hinged doors, one of which is opened when supplying fuel, and the others may
also be opened at intervals for clearing the fire-bars. In the bottom of each
chamber are made a number of openings or perforations communicating with
a flue beneath, which flue communicates direct with the adjoining chamber,
and bas also a branch leading from it to the fire-places of such chamber,
either of which communications may be opened or closed by dampers.
Openings in the roof of the chambers communicate with flues which lead
direct to the chimney. When a number of chambers or kilns are employed
I construct them in two parallel rows with a tramway between them, and
prefer to make the doors of each row opposite each other on each side of the
tramway; or if desired the fire-places in each row may be opposite each other,
and the kiln doors on the outer sides of the kilns. In using these kilns I
take the hot air from that chamber in which the bricks are cooling, and
cause it to pass by the bottom flue through the fire-place or places of the
adjoining chamber in order to support combustion, none but hot air entering
such chamber where the burning is in progress. From the chamber in which
the bricks are being burnt the hot air passes downwards through the bottom
of the kiln into the flue beneath, and is thereby conveyed into the next
adjoining chamber or chambers through the openings in the floor, with a view
to beating the bricks therein preparatory to their being burnt, and thereby
utilizing the waste heat from the burning bricks. These last chambers com-
municate direct with the chimney by the openings in the roof and the flues
above them. By the time the bricks in the first-mentioned chamber have
been sufficiently cooled to be removed, the bricks in the next one are burnt,
and the first chamber may be refilled whilst the hot air from the second
passes through the fire-grates of the third kiln or chamber, and so on
throughout the series, the process being continuous.
The drying apparatus consists of a closed chamber provided with a per-
forated top and bottom, and underneath the bottom perforated plate there is
a chamber, into which hot and cold air is admitted in regulated proportions
through pipes and valves for that purpose, according to the temperature
required in the drying chamber. In the air chamber below I propose to
employ a set of revolving perforated arms or blades, which serve to mix the
hot and cold air together before they are drawn up into the drying chamber;
other means may be employed for mixing the hot and cold air together, but it
is essential that such admixture be effected before the air enters the drying
chamber. The hot air employed is obtained from the upper flues in the kiln
before referred to, a pipe or pipes being connected therewith for that purpose,
and provided with branches and valves, so as to enable the hot air to be

page_text: taken from any one of such flues. Above the upper perforated plate in the
drying chamber there is an exhauster which draws up the warm air through
the bricks in the drying chamber, and expels it with the moisture through a
chimney.
The bricks to be dried are taken direct from the machine and placed in
tiers upon a truck or trucks, which are at once run into the drying chamber
upon rails or tramways for that purpose. The doors of the chamber having
been tightly closed, air at a temperature of about 90° Fahrenheit is caused
to pass through them for the space of about five minutes, during the next five
minutes the temperature of the air may be elevated to about 120°, and during
the five minutes succeeding the temperature may be increased to 160° and
upwards, thus effecting the drying in a gradual yet rapid manner, each
charge of bricks being effectually dried ready for stacking in the kiln in
about fifteen minutes.
The trucks are then run out of the drying chamber and conveyed along
tramways direct to the kilns where the bricks are stacked for burning. The
temperature of the air in the drying chamber is regulated to any degree by
admitting more or less hot air in proportion to the cold air by means of the
valves for that purpose.