IMPROVEMENTS IN KILNS FOR BURNING BRICKS, TILES, AND OTHER OBJECTS
Year: 1878

page_text: PROVISIONAL SPECIFICATION left by David Johnson at the Office of the
Commissioners of Patents on the 23rd January 1878.
DAVID JOHNSON, of the City and County of Bristol, Fire-brick and Sanitary
Pipe Manufacturer. "IMPROVEMENTS IN KILNS FOR BURNING BRICKS, TILES, AND
OTHER OBJECTS."
According to this Invention I arrange a kiln in a circular form or approaching
thereto, and I subdivide it into a number of fan-shaped chambers independent of
one another, but which may also at times, as required, be put in communication
with one another.
.
The chimney is in the middle, and the lower part of the same is by preference
subdivided into as many parts as there are chambers. I arrange flues, say, three in
number, under the floor of each compartment, by preference in the middle portion
of same, and converging or uniting into one towards the chimney; the remaining
part of the floor I make " checkered," or with suitable openings for letting the
heat pass down below the floor, and I make the side walls of the floor flues
" checkered or open-worked for receiving this heat, which then passes off to the
chimney. The kiln is built round the central chimney, and is dome-shaped. Each
compartment I form with a "wicket" in the middle, and, say, two firing holes on
each side. I thus uniformly distribute the heat, which, where it is highest, has the
greatest area or volume of goods to act upon; the flues below the floor may have
arched covers or tops made of fire-clay.
"
In each chamber a short distance from the outside wall I arrange a low fender or
bridge wall for protecting the bricks from the direct action of the fire, and for pre-
venting the discoloration of same. Holes, which may be closed by covers or dampers,
are provided in the upper part of the kiln for letting off the steam, and for dropping
fuel through, at the same time serving as holes for observation of the progress of
burning.
The mode of the working of this kiln is as follows:-Filling, say, compartment
No. 2 with bricks or other objects to be burnt, the damper or dampers leading to
the adjoining compartment No. 1 are opened; this compartment, No. 1, is charged
with bricks, the burning of which has just been completed, and the waste heat from
this compartment is now made use of to dry and heat the raw unburnt bricks in No. 2

page_text: compartment; that being done, more or less as convenient, the communicating
dampers are closed, the fires are lit in compartment No. 2, and the bricks burnt
therein. Meanwhile the charge in compartment No. 1 is cooling down, and may
then be drawn. While the charge in No. 2 is burning, No. 3, the next following
compartment, is being charged with raw bricks, and when the charge in No. 2 is
burnt the dampers are opened between No. 2 and No. 3, in order that the waste
heat from No. 2 may dry and heat the fresh charge in No. 3, and so on in succession
as desired.
Two or more or all chambers may thus be worked simultaneously, or in rotation,
or one chamber only if desired.
For drying and burning bricks of semi-dry clay the heat from the fire holes,
instead of passing downwards to the bottom flues, may be partly or wholly led
upwards to the chimney by suitable top flues, dampers being provided and suitably
adiusted for that purpose.
"A