IMPROVEMENTS IN FURNACES TO BE USED IN THE MANUFACTURE OF GLASS, AND IRON, AND STEEL, AND FOR OTHER LIKE PURPOSES
Year: 1865

page_text: LETTERS PATENT to John Frederick Boetius, of Smethwick, in the
County of Stafford, Civil Engineer, for the Invention of "IMPROVEMENTS
IN FURNACES TO BE USED IN THE MANUFACTURE OF GLASS, AND IRON, AND
STEEL, AND FOR OTHER LIKE PURPOSES."-A communication from abroad by:
Honning Rective of Schonenstain
near Obernkirchen Germany
PROVISIONAL SPECIFICATION left by the said John Frederick Boetius
at the Office of the Commissioners of Patents, with his Petition, on the
15th August 1865.
I, JOHN FREDERICK BOETIUS, of Smethwick, in the County of Stafford,
Civil Engineer, do hereby declare the nature of the said Invention for:
"IMPROVEMENTS IN FURNACES TO BE USED IN THE MANUFACTURE OF GLASS, AND
IRON, AND STEEL, AND FOR OTHER LIKE PURPOSES," to be as follows
The said Invention consists in constructing in the manner herein-after
described the fire-places and parts immediately connected therewith of the said
furnaces, whereby economy in the consumption of fuel, and the suppression
of smoke are effected, as well as an intense and uniform heat produced.
In applying the said Invention to furnaces for melting glass the parts are
constructed and arranged as follows:-The upper part of the furnace is
constructed in the ordinary way. The fire-places of the furnace are situated:
below the ground line and are of à greater depth than ordinary fire-places.
The side walls. of the fire-places are inclined and the two fire-places are.

page_text: separated from each other by a vertical wall. At the bottom of the inclined
and vertical walls of each of the fire-places the grate is fixed, which may
either be horizontal or inclined, and below the grates is the ash-pit. The
fuel is fed to the fire-places through openings at the ends of the furnaces and
at the ground line, the said fuel descending gradually by its own weight along
the inclined sides of the fire-places to the grates at the bottoms thereof. The
upper end of each of the fire-places opens by a central port or passage into
the body of the furnace, the said ports or passages being made through the
siege or bed of the furnace. Between the fire-places and the outer walls of
the furnace broad flat vertical slits or channels are left. These slits or
channels communicate at bottom by means of openings with the ash-pit, and
at top by a series of horizontal channels situated under the bed of the furnace
with the ports or passages already described at the tops of the fire-places, the
said horizontal channels opening into the said ports on each of their four
sides. The bottoms of the vertical slits or channels are provided with sliding
valves by which the quantity of air passing through them can be regulated.
In the vertical wall separating the two fire-places vertical slits or channels
are also made, their lower ends opening into the ash-pit and their upper ends
into the horizontal channels herein-before described. "
The combustion of the fuel in the fire-places takes place differently at
different parts. In that part immediately above the grate complete com-
bustion takes place, the carbonic acid gas evolved being reduced to carbonic
oxide as it ascends through the incandescent fuel in the middle of the heap,
and this gas mixes with the products of distillation evolved from the top of
the beap situated in the space above the fuel from whence the gaseous
mixture ascends through the ports or passages at the tops of the fire-places
into the body of the furnace. As this gaseous mixture; enters the gas "ports
a copious amount of heated air is passed into it from the openings.on each`
of the sides of the said ports, the air conveyed to the said ports: being heated
in its passage through the vertical slits or channels berein-before described in
the side walls and vertical middle wall of the fire-places. The mixture of
gas and heated air is thus made very intimate, and perfect combustion and the
suppression of smoke thereby result. The currents of air passing between the
walls of the fire-places and the outer walls of the furnace keep them: cool and
preserve them from the destructive effects of the heat. The waste heat from s
the furnace may be economized by allowing it to: pass into a glass'annealing
furnace or a calcining furnace or furnaces.
..In applying the said Invention to heating furnaces or other reverberatory
furnaces used in the manufacture of iron and steel and other metals one'

page_text: fire-place: only is used, the said fire-place having two inclined sides, othe
middle vertical wall being dispensed with.: The top of the fire-place:
opens into a chamber between the fire-place and body of the furnace,
into which chamber the gaseous mixture from the fire-place enters,, where
it combines with the heated air supplied by. vertical and horizontal: flues or
passages constructed in the manner herein-before described with reference to.
glass-melting furnace...
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Frederick Boetius in the Great Seal Patent Office
on the 10th February 1866.
'
:
TO ALL TO WHOM. THESE PRESENTS SHALL COME, I, JOHN.
FREDERICK BOETIUS, of Smethwick, in the County of Stafford, Civil Engineer,
send greeting.
•
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifteenth day of August, in the year of our Lord
One thousand eight hundred and sixty-five, in the twenty-ninth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the.
said John Frederick Boetius, Her special licence that I, the said John,
Frederick Boetius, my executors, administrators, and assigns, or such others.
as I, the said John Frederick Boetius, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to time
and at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United, Kingdom
of Great Britain and Ireland, the Channel Islands,; and Isle of Man, an
Invention for "IMPROVEMENTS IN FURNACES TO BE USED IN THE MANUFACTURE
OF GLASS, AND IRON, AND STEEL, AND FOR OTHER LIKE PURPOSES," a communication
to me from abroad by Henning Boetius, of Schauenstein, near Obern-
kirchen, Germany, upon the condition (amongst others) that I, the said
John, Frederick Boetius, my executors or administrators, by an instru-
ment in writing under my, or their, or one of their hands and seals, should
particularly describe and ascertain the nature of the said Invention, and in
what manner the same was to be performed, and cause the same to be filed in
the Great Seal Patent Office within six calendar months next and immediately.
after the date of the said Letters Patent.
1
NOW KNOW YE, that I, the said John Frederick Boetius, do hereby
declare the nature of the said Invention, and in what manner the same

page_text: is to be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say:-
The said Invention consists in constructing in the manner herein-after
described, the fire-places and parts immediately connected therewith of the
said furnaces, whereby economy in the consumption of fuel, and the suppression
of smoke are effected, as well as an intense and uniform heat produced.
In applying the said Invention to furnaces for melting glass, the parts are
constructed and arranged as follows:-The upper part of the furnace is con-
structed in the ordinary way. The fire-places of the furnace are situated
below the ground line, and are of. a greater depth than ordinary.fire-places.
The side walls of the fire-places are inclined, and the two fire-places are
separated from each other by a vertical wall. At the bottom of the inclined
and vertical walls of each of the fire-places the grate is fixed, which may
either be horizontal or inclined; and below the grates is the ash-pit. The
fuel is fed to the fire-places through openings at the ends of the furnace and
at the ground line, the said fuel descending gradually by its own weight along
the inclined sides of the fire-places to the grates at the bottoms thereof. The
upper end of each of the fire-places opens by a central port or passage into
the body of the furnace, the said ports or passages being made through the
siege or bed of the furnace. Between the fire-places and the outer walls of
the furnace broad flat vertical slits or chaunels are left; these slits or channels
communicate at bottom by means of openings with the ash-pit, and at top by
a. series of horizontal channels situated under the bed of the furnace with the
ports or passages, already described, at the tops of the. fire-places, the said
horizontal channels opening into the said ports on each of their four sides.
The bottoms of the vertical slits or channels are provided with sliding valves,
by which the quantity of air passing through them can be regulated. In the
vertical wall separating the two fire-places vertical slits or channels are also
made, their lower ends opening into the ash-pit, and their upper ends into the
horizontal channels herein-before described.
The combustion of the fuel in the fire-places takes place differently at
different parts. In that part immediately above the grate complete com-
bustion takes place, the carbonic acid gas evolved being reduced to carbonic
oxide as it ascends through the incandescent fuel in the middle of the
heap, and this gas' mixes with the products of distilla:ion (evolved from
the top of the heap) situated in the space above the fuel, from whence the
gaseous mixture ascends through the ports or passages at the top of the fire-
places into the body of the furnace. As this gaseous mixture enters the gas
ports a copious amount of heated air is passed into it from the openings on

page_text: each of the sides of the said ports, the air conveyed, to the said ports being
heated in its passage through the vertical slits or channels herein-before
described in the side walls and vertical middle wall of the fire-places. The
mixture of gas and heated air is thus. made very intimate, and perfect com-
bustion and the suppression of smoke thereby result. The currents of air
passing between the walls of the fire-places and the outer walls of the furnace
keep them cool, and preserve them from the destructive effects of the heat.
The waste heat from the furnace may be economized by allowing it to pass
into a glass annealing furnace, or into a calcining furnace or furnaces.
In applying the said Invention to heating furnaces or other furnaces used
in the manufacture of iron and steel and other metals, one fire-place only is
used, the said fire-place having two inclined sides, the middle vertical wall
being dispensed with. The top of the fire-place opens into a chamber between
the fire-place and the body of the furnace, into which chamber the gaseous
mixture from the fire-place enters, where it combines with the heated air,
supplied by vertical and horizontal flues or passages constructed in the manner
herein-before described with reference to a glass melting furnace..
Having explained the nature of the Invention I will proceed to describe
with reference to the accompanying Drawing, the manner in which the same,
is to be performed.
Figures 1, 2, 3, and 4, represent a glass-melting furnace provided with
improvements according to the said Invention. Figure 1 being a longitudinal,
section of the furnace through the line A, A, Figure 2; Figure 2, a cross
section of the same through the line B, B, Figure 1; Figure 3, a horizontal
section or plan through the line C, C, Figure 1; and Figure 4, a horizontal
section or plan through the line D, D, Figure 2. The same letters of
reference indicate the same parts in Figures 1, 2, 3, and 4.
A, A', are the two fire-places of the furnace situated below the ground line,.
and separated by a vertical hollow wall or saddle piece C. The outer side
walls of the said fire-places are inclined as best seen in Figure 1: The walls
of the fire-places are made of fire-bricks or other fireproof material. At the
bottom of the inclined and vertical walls of each of the fire-places A, A¹, the
grates marked respectively d, d, are fixed, which may either be inclined as.
represented, or horizontal. Air for supporting the combustion of the fuel in
the fire-places is supplied from the ash-pit d. The fuel is fed to the fire-
places through openings e, el, at the ends of the furnace and at the ground.
line, the said fuel descending by its own weight along the inclined sides of the
said fire-places to the grates d, d'. The upper end of each fire-place A, A',
opens by a central opening or port marked respectively D, D', with the body.

page_text: of the glass furnace D³, the said ports or openings being made through the
siege or bed of the furnace, as seen in the Drawing. Between the fire-places
and the outer walls of the furnace broad flat vertical slits or channels marked
3, s¹, are made (see Figures 2 and 4). The said slits or channels s, s', open
at bottom into the horizontal passages a, a¹, and the latter into the ash-pit d²,
and the said slits 5, 8, open at top into a series of horizontal channels b, b,
situated under the bed of the furnace, the said. channels b, b, opening into the
ports D, D, on each of their four sides (see Figure 4). The ends of the
passages a, a', opening into the ash-pit d² are provided with sliding valves or
dampers d³, d, by which the quantity of air passing through the slits or
passages s, s¹; can be regulated. In the vertical wall C separating the two
fire-places A, A', vertical shafts or channels. 1, 1, are made opening.at bottom
into the ash-pit d², and at top into the horizontal slits. or channels. b. Air
from the ash-pit d² is thus conveyed by the passages or channels. 8, 8, 1, 1, and
b, b, to the upper part of the fire-places A, A¹, the said air being heated in its
passage through the said channels.. By this means the walls of the fire-places
are kept cool and preserved from the destructive effects of the heat.. In using
the furnace the fuel, is introduced into the fire-places A, A¹, through the ends
e, e¹, which fuel moves slowly along the inclined sides of the fire-places to the
grates at the bottom thereof. The heat of the fuel immediately. above. the
grates where perfect combustion takes place drives off the volatile hydro-
carbons from the upper layer of fuel, which as the under layer is consumed
gradually descends upon the grates in the form of coke. The carbonic acid
evolved by the combustion of the said coke on the grates is reduced to
carbonic oxide as it ascends through the incandescent fuel in the middle of
the heap, and this gas in admixture with the hydrocarbons evolved from the
upper layer of fuel and the nitrogen of the air ascends through the ports or
passages D, D¹, into the body D2 of the furnace. As the gaseous combustible
mixture enters the ports or passages D, D¹, a copious amount of heated air is
passed into it from the channels b, b, on each side of the said ports, the said
air being supplied to and heated by the passages or slits 8, st, and 1, F, in the
manner herein-before explained. The mixture of gas and air is by this
arrangement made very intimate, and perfect, combustion and the suppression
of smoke thereby result. The heat supplied to the furnace D2 after heating
the said furnace may be allowed to pass into calcining furnaces connected
with the furnace, as represented in the Drawing, or into a glass annealing
furnace. The waste heat of the furnace is thus economized. In some cases
the hollow vertical wall between the two fire-places may be dispensed with,
and an arch. thrown across the fire-place, and instead of the two ports one

page_text: large port may be situated in the middle of the fire-place: For large furnaces
where one fire-place is insufficient to produce the requisite quantity of gaseous
mixture, two or more fire-places may be placed side, by side and across the
furnace, the middle hollow wall being dispensed with. When more than two
fire-places are used the gas port is situated in the middle of each fire-place;
the air slits or channels being situated' between 'two of the fire-places and
between the end fire-places and outer walls.
Figures 5, 6, and 7, represent a heating furnace for heating or: melting
iron or steel or other metals, the parts of which are arranged, according to the
said Invention. Figure 5 representing a longitudinal vertical section of the
furnace through the line H, H, Figure 6; Figure 6, a. cross section through
the line I, I, Figure 5; and Figure 7, a horizontal section through the
line K, K, Figure 5. In this arrangement of my Invention one fire-place
only with inclined sides is used (see Figure 6), the central wall being omitted.
The air required for the perfect combustion of the gaseous mixture passes
from the ash-pit d by the openings h, h', ascending the passages i, k, behind
the walls of the fire-place, and enters the mixing chamber E with the gaseous
combustible mixture produced in the fire-place, the said air being heated on
its way to the said mixing chamber, as herein-before described.
Figures 8, 9, and 10, illustrate the application of the said Invention to a
furnace for the reduction of zinc ores. Figure 8 representing a horizontal
section of the furnace through the line E, E, Figure 10; Figure 9, a vertical
section of the same through the line F, F, Figure 10; and Figure 10 also a
vertical section of the same through the line G, G, Figure 9. In this
arrangement the air ascends through the passages m, m², and o, o, and enters
the gas ports F, F, from one side, and air passing through the channel p
from the outside of the furnace enters by the passages o¹, o, into the gas
ports F, F, on the other side. The heated currents of air thus mix with the
gaseous products evolved from the fire-place, and ensure a perfect combustion
of the same, as herein-before explained.
In each of the furnaces represented the fire is regulated by the stoker by
keeping the grate more or less free from clinkers, and admitting more or less
air by means of the valves or dampers through the slits or channels described
and represented.
Having now described the nature of the said Invention, and the manner in
which the same is to be performed, I wish it to be understood that I do not
limit myself to the precise details herein described and represented in the
Drawing, as the same may be varied without departing from the nature of the
said Invention; but I claim as the said Invention the improvements in

page_text: furnaces to be used in the manufacture of glass, and iron, and steel, and for
other like purposes herein-before described and illustrated in the accompanying
Drawing, that is to say, constructing around the outer walls: of the fire-places
situated below the ground line or around the outer walls, and between the
fire-places, passages for conveying air to the combustible gases evolved from
the fuel, by the heated walls of which said passages the air is heated before
being mixed with the said combustible gases, substantially as herein described
and illustrated."
In witness whereof, I, the said John Frederick Boetius, have hereunto
hand and seal, this Twentieth day of January, in the year of
set
my
our Lord One thousand eight hundred and sixty-six.
JOHN FREDERICK BOETIUS: (L.s.).
Witness,
WILHELM GROTE,
Schauenstein, near Obernkirchen,
Germany.