IMPROVEMENTS IN APPARATUS OR APPLIANCES FOR EFFECTING A MORE PERFECT COMBUSTION OF FUEL IN FURNACES
Year: 1879

page_text: LETTERS PATENT to Wilhelm Heiser, of Berlin-Moabit, in the German Empire,
for the Invention of "IMPROVEMENTS IN APPARATUS OR APPLIANCES FOR
EFFECTING A MORE PERFECT COMBUSTION OF FUEL IN FURNACES."
Sealed the 12th December 1879, and dated the 23rd June 1879.
PROVISIONAL SPECIFICATION left by the said Wilhelm Heiser at the Office
of the Commissioners of Patents on the 23rd June 1879.
WILHELM HEISER, of Berlin-Moabit, in the German Empire.
"IMPROVEMENTS
IN APPARATUS OR APPLIANCES FOR EFFECTING A MORE PERFECT COMBUSTION OF
FUEL IN FURNACES."
The present Invention has for its object to effect a more perfect combustion of
fuel in furnaces by providing for the unconsumed gases and smoke passing
therefrom a copious supply of air heated to a considerable degree and caused to mix
intimately with such gases and smoke. For this purpose there is provided at a
certain height above the fuel on the firegrate a longitudinal tube of firebrick or
other suitable refractory material of large diameter, communicating at the front end
with the furnace, and at the back end with the flue leading to the chimney. The
communication with the furnace is so arranged that the flames, smoke, and gases,
before entering the tube, bave to pass round the greater part of the outer surface
thereof, thereby heating the tube to a high degree. Within the walls of the tube
are formed longitudinal passages which communicate at the back end with two side
flues formed in the brickwork on each side of the furnace, and leading to air
openings on each side of the furnace door, which openings are provided with
regulating dampers or slides. The front ends of said passages being made to open
into the furnace at points in the periphery of the tube surrounding the central passage
thereof, it will be seen that atmospheric air entering the two side flues will bo
conducted therein to the back end of the passages in the tube, and in travelling
[Price R71

page_text: forward in the latter will become highly heated before issuing from the open front
ends thereof, so that on impinging upon and becoming intimately mixed with the
flames, smoke, and gases that are passing into the open end of the tube, the air will
effect the perfect combustion of such smoke and gases while travelling through the
central passage of the tube towards the chimney flue.
The said passages in the walls of the tube may be conveniently formed by fitting
an inner tube within the outer one with an annular space intervening between the
two, which is divided into separate longitudinal passages by means of longitudinal
ribs formed either on the inner surface of the outer tube or on the outer surface of
the inner one.

page_text: can be regulated to the best advantage, and a portion of the structure of the front
at E is made removeable to give access for clearing the central flues.
The Figures
on Sheet II. shew a similar arrangement applied to a boiler having the fire below
its front part. Fig. 1 is a longitudinal section, Fig. 20 a front elevation, Fig. 3º a
sectional plan on X, X, and Figs. 40 and 50 are transverse sections respectively on
Y, Y, and Z, Z. In this case the air entering as already described in regulated
quantity the flues a, a, return along b, b, flows again back along c, c, crosses the end of
the space by the passages e', returns through the channels f, and mingling with the
smoke and gases rising from the fire into the space h above it, the mixture in vivid
combustion passes along the tube g to the boiler flues. In this arrangement the
front part of the boiler forming a cover to the space h receives heat from the smoke
and hot gases on their way to g. The Figures on Sheet III. shew the Invention
applied to the internal fire flues of a boiler. Fig. 1b is a longitudinal section
through one of the flues, Fig. 2b is a front elevation, Fig. 3b is a sectional plan
showing the upper part of one fire flue and the lower part of the other, Figs. 4b and
5b are respectively half sections on Y, Y, and Z, Z. In this arrangement the air
enters by channels a formed in the lower part of the ash pit between the plate of
the flue and a more flatly curved plate attached at its edges to the Blue with stays
between. The channels a communicate behind the bridge with flues b formed
under a retort shaped tube g. The air after flowing backward along the flues b
returns along the channels between the crown of the tube g and the crown of the
boiler flue, the current being divided into separate streams by ribs projecting from
9.
The heated air at the front mouths of the channels f meets the smoke and gases
from the fire and completes their combustion as the moisture passes along the tube
to the boiler flues.
g
Although I have described several different arrangements of apparatus suitable
for different types of boilers, it may be readily understood that these arrangements
may be varied to suit other types of boilers and to adapt the Invention to furnaces
for other heating purposes.
Having thus described the nature of my Invention and in what manner the same
is to be performed, I hereby declare that I make no general claim to effecting
complete combustion of the smoke and gases proceeding from a fire by mingling
them while hot with heated air, but I claim in respect of apparatus operating in
that way for that purpose,
The combination of subdivided air supply flues or channels heated by conduction
through their walls with a refractory flame tube at the mouth of which the smoke
and gases from the fire meet the divided streams of heated air, so that the mixed
air and gases pass through the tube in a state of combustion, substantially as
herein described.
In witness whereof, I, the said Wilhelm Heiser, have hereunto set my hand
and seal, this Fifteenth day of December, in the year of our Lord One
thousand eight hundred and seventy nine.