IMPROVEMENTS IN FURNACES AND APPARATUS CONNECTED THEREWITH, MORE ESPECIALLY DESIGNED FOR AN IMPROVED METHOD OF HEATING GAS RETORTS
Year: 1872

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine,
Lake, & Co., Patent Agents, Southampton Buildings, London,
for the Invention of "IMPROVEMENTS IN FURNACES AND APPARATUS
CONNECTED THEREWITH, MORE ESPECIALLY DESIGNED FOR AN IMPROVED METHOD
OF HEATING GAS RETORTS."-A communication from abroad by Emile
Muller and Auguste Eichelbrenner, both of Paris, France, Civil
Engineers.
PROVISIONAL SPECIFICATION left by the said William Robert Lake
at the Office of the Commissioners of Patents, with his Petition,
on the 22nd January 1872.
I, WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co.,
Patent Agents, Southampton Buildings, London, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN FURNACES AND APPARATUS
CONNECTED THEREWITH, MORE ESPECIALLY DESIGNED FOR AN IMPROVED METHOD OF
HEATING GAS RETORTS," a communication, to be as follows:-
and
This Invention relates to heating furnaces by oxide of carbon, tar,
small combustibles, and is more especially designed for the furnaces of
retorts.for making gas for illuminating or heating purposes.

page_text: which are not in anywise displaced and which lie near the chimney as
usual. There is nevertheless an advantage in placing the retorts in
vertical rows, one above the other and not quincuncially, this arrange-
ment giving greater simplicity of construction and preventing irregularity
in the settling.
Moreover by arranging between the ends of the retorts and the hopper
a passage H, I can bring upon the mass of incandescent fuel at I tar or
any other combustible liquid poured in at the top K; I can also burn
these combustible liquids by introducing them with solid fuel into the
hopper. The combustion of the tar produces great heat, and permits a
saving of other fuel; it will be therefore henceforth a great advantage to
have this substance in gas works, although its presence has been hitherto
a source of expense and inconvenience.
For two or three furnaces I may employ a single hearth, distributing
the heat uniformly in the furnaces. For a greater number of furnaces I
also employ a single hearth; but then the heating of the air destined for
the combustion of the oxide of carbon is effected more conveniently in a
special heat recuperator. For this purpose a single passage placed under
the furnaces distributes in cach one of them the oxide of carbon, while
at each side a second passage brings the heated air necessary for
combustion.
The substitution of heating by oxide of carbon for the ordinary heating
has various advantages of which I will only name the following, viz. :—
Diminution in the draught in such proportions that the gas leaves the
furnace and enters the chimney with a very low temperature, thereby
economizing fuel, and moreover there is no accumulation of the ashes in
the furnaces upon the retorts, so that a much better heating effect is
obtained.
"
30
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Robert Lake in the Great Seal Patent
Office on the 19th July 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London, send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-second day of January, in the year
of our Lord One thousand eight hundred and seventy-two, in the thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said William Robert Lake, Her special licence
that I, the said William Robert Lake, my executors, administrators, and
assigns, or such others as I, the said William Robert Lake, 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 AND APPARATUS CONNECTED THEREWITH, MORE
ESPECIALLY DESIGNED FOR AN IMPROVED METHOD OF HEATING GAS RETORTS," a
communication to me from abroad by Emile Muller and Auguste
Eichelbrenner, both of Paris, France, Civil Engineers, upon the con-
dition (amongst others) that I, the said William Robert Lake, my
executors or administrators, by an instrument 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
Seal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
"
NOW KNOW YE, that I, the said William Robert Lake, do hereby
declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained
in and by the following statement, reference being had to the accom-
panying Drawing forming a part of this Specification
The ordinary mode of heating retorts in the preparation of coal gas
necessitates the employment of a special fireman and a great consump-
tion of coke or coal, while it does not permit the utilization of the tar
produced; it also precludes the use of small coal and other com-
bustibles commonly at hand. The means herein-after described permit
the employment by a regular and continuous feed not only of coke but
also of bituminous or anthracite coal and other combustibles, separately
or mixed, for heating either the new furnaces or old furnaces whose
transformation may be effected very quickly, with but a short stoppage
of their working, and at a very slight cost.

page_text: DESCRIPTION OF THE DRAWING.
Figure 1 is a transverse section, and Figure 2 is a longitudinal section
of a furnace embodying this Invention.
The ordinary fire-place is not used, the fire-bars are removed (or covered
with refractory tiles if their retention is desired), and the ash-pit is filled
up. The brickwork of the furnace behind and at its centre is provided
with an additional thickness or lining, below which is placed a small
grate A, and above it a hopper B enlarged towards its base. Two or
three times in twenty-four hours this hopper is filled to the top with
combustibles which descend as the portion lying on the grate is consumed.
The combustible gas resulting from the incomplete combustion or
distillation produced at the lower part of the aforesaid pyramidal
hopper B passes to the interior of the furnace, either directly or through
a flue built of refractory bricks or pieces D placed at the base of the
furnace. Several orifices E made in the arch of the said flue permit this
combustible gas to disengage itself in the interior of the furnace, that is
to say, in the chamber which contains the distilling retorts. Other
orifices F placed at the side of the above admit air for the combustion of
gas. This air is first warmed by circulating in passages placed under
the hearth of the furnace or enclosed in other passages by which the
products of combustion pass from the furnace to the chimney. Thus I
can restore to the air required for combustion a great portion of the heat.
carried up the chimney by the burned gases, that is to say, I can obtain
in a more or less complete manner what is termed the recuperation of
the heat. Furthermore, slabs of refractory earth permit the partial or
total closing of the aforesaid orifices, both those for the disengagement
of the combustible gas and those for the admission of the air. Thus the
activity of the combustion may be augmented or diminished at will at
the different points of the furnace, and consequently a perfect equality
of temperature may be obtained. In the majority of cases it is best to
place the hopper or the fire-place at the rear of the furnace; but this
arrangement may be modified to suit local circumstances. The same
may be placed at the side or in front of the gas furnace below the hearth,
or in any other suitable or convenient position. The flue in which the
gaseous products of combustion pass from the furnace is ordinarily
placed in the centre of the furnace at the lower part of the same, but its
position may be modified according to circumstances. In certain cases

page_text: it is advantageous to place between the fire-place A and the flue D a
register which permits the isolation of the fire-place from the furnace.
Furthermore, the passages for heating the air to be used for combustion
may be replaced by one of the apparatus at present employed for the
recovery of heat, such for example as the "Ponsard" recuperator, the
"Siemens
regenerator, or the brick calorifier of Muller, either with
simple circulation of the air as in Figure 4, or multiple as in Figure 5;
or I may use the calorifier of hollow bricks, Figure 3, whose arrangement
"
Furthermore, the passages for heating the air to be used for combustion
may be replaced by one of the apparatus at present employed for the
recovery of heat, such for example as the "Ponsard" recuperator, the
"Siemens " regenerator, or the brick calorifier of Muller, either with
simple circulation of the air as in Figure 4, or multiple as in Figure 5 ;
or I may use the calorifier of hollow bricks, Figure 3, whose arrangement
1s as follows:—
Hollow bricks of suitable dimensions are placed in juxtaposition
horizontally and form a series of passages through which passes the air to
be heated. A number of layers, more or less considerable, of these bricks
are superposed in a chamber of masonry with an interval between the
layers. Each layer communicates at one end with the layer immediately
above it, and at the other end with the layer immediately below it. The
cold air enters the lowest layer and passes through the hollow bricks
continually rising. These hollow bricks are heated by the waste heat
which enters the chimney after passing through the various layers of
bricks; the heated gas enters by the top of the chamber descending in a
serpentine course (like that of the air in rising), and escapes at the base
of the said chamber; thus the heated air and gas travel parallel to each
other, but in opposite directions. Provision is made for cleaning by
providing plugs at the ends of the chamber. As to the joints of the
bricks at their extremities, (which alone must be closed,) they are fitted
with bevelled surfaces as shewn in the Drawing ;. moreover the bricks bear
upon slabs at their joints, and these joints may be covered with slabs at
the upper part. Thus these furnaces of slow combustion may have
applied to them apparatus for the recovery of the heat.
At the commencement of this description there has been indicated the
possibility of burning in the said fire-places with the hopper other
combustibles besides coke, as for example coal, either close burning or
flaming, tar, and various combustible oils, and other liquids. In using
tar the same may be poured continuously or otherwise into the upper
part of the hopper; or it may be found most convenient to have it
supplied continuously to the lower part of the hopper by a tube T passing
through the wall of the furnace above the solid combustibles in ignition,
sec Figure 2. A third method would be to pour it in by the tube $

page_text: between the hopper and the furnace. Furthermore, in certain cases the
heating of the furnaces may be effected with small coal, chips, sawdust,
tan, and the like by slightly modifying the base of the hopper, and
making it analogous to that commonly employed in saw mills and
tanneries.
The distilling retorts may be often advantageously arranged not quin-
cuncially as usual, but in vertical rows one over the other, as shewn in
Figure 6, for furnaces of 2, 3, 4, and 6 retorts. The furnace has thus
relatively smaller means of development, that is to say, a smaller cooling
surface, moreover the setting of the retorts is more easily and strongly
made.
In Figures 1 and 2 A is the fire-place, either with or without the
grate behind the furnace; B is the covered hopper filled with com-
bustibles; A³ is the place for the slow combustion; D, D, is the flue for
the gas and combustible vapours; E, E, are orifices for the disengage-
ment of the combustible gas; F, F, are the orifices for conducting the
air for the combustion of the gas; Q, Q, are the registers for regulating
the admission into the furnace of the combustible gas and heated air;
U, U, are the escape apertures of the spent gas which enters the chimney
flue L passing through the horizontal passage, then by the passage I,
and descending by the vertical passage K; M is the horizontal passage
for the admission of the cold air, which is warmed in passing through it,
and in traversing successively the other horizontal passages M, O, P;
Lis the chimney flue conducting the cooled gas to the main vertical
chimney of the works; R, R, are the inspection plugs; S is the tube
down which may be poured the tar or other combustible liquids to be
utilised with the solid combustible in the hopper B; C is the cover of
the hopper; it may be perforated with a small hole for the reception of
the lower end of a tube or syphon, whose upper end is supplied con-
tinuously with tar or other liquid combustibles; T is the orifice whereby
a stream of tar or other liquid combustible may be made to flow upon
the top of the bed of solid combustible in a state of ignition.
Figure 3 illustrates the method of heating the air by hollow horizontal

page_text: whole of these arrangements being applicable to existing furnaces as
well as to new furnaces.
In witness whereof, I, the said William Robert Lake, have hero-
unto set my hand and seal, this Nineteenth day of July, in
the year of our Lord One thousand eight hundred and seventy-
Witness,
W. J. LOWE.
W. ROBT. LAKE. (L.S.)