Iм- PROVEMENTS IN BLAST FURNACES AND CUPOLAS, AND IN RECOVERING OR COLLECTING THE PRODUCTS THEREOF.
Year: 1874

page_text: LETTERS PATENT to Henry Aitken, of Falkirk, in the County of
Stirling, North Britain, Coal Master, for the Invention of “Iм-
PROVEMENTS IN BLAST FURNACES AND CUPOLAS, AND IN RECOVERING OR
COLLECTING THE PRODUCTS THEREOF.
"
Scaled the 10th July 1874, and dated the 16th February 1874.
PROVISIONAL SPECIFICATION left by the said Henry Aitken at.
the Office of the Commissioners of Patents, with his Petition, on
the 16th February 1874.
I, HENRY AITKEN, of Falkirk, in the County of Stirling, North
Britain, Coal Master, do hereby declare the nature of the said Invention
of "IMPROVEMENTS IN BLAST FURNACES AND CUPOLAS, AND IN RECOVERING OR
COLLECTING THE PRODUCTS THEREOF," to be as follows, that is to say :-
This Invention has for its object in the first place to carry on smelting)
or melting operations with blast furnaces or cupolas of diminished
height, and it consists in the construction of a chamber of larger.
diameter than the body of the furnace at the upper part, so that a ledge.
or shelf is formed upon which the materials used in the furnace are

page_text: charged. This enlarged chamber is covered over with a dome of fire-
brick or other refractory substance, and the top or sides are provided
with a bell and cone or charging doors lined with fire-brick or other
refractory material, and passages or openings are formed in it above the
level of the materials in the blast furnace, through which air (preferably
heated) is forced or drawn at numerous points so as to ignite and burn
the gases passing off from the materials, and thereby raising the
materials in the enlarged chamber to a very high temperature, and so
facilitating the smelting or melting operations; or the top of the furnace
or cupola may be made of a much larger area than usual, and without
the ledge, thereby exposing as much as possible of the materials to the
action of the heated gases as before mentioned. In this case it is
preferred to make the furnace with a uniform angle from the beginning
of the "boshes" to the level, or nearly to the level, of the materials at the
top of the blast furnace or cupola. It is preferred to have the material
at the top of the furnace as level as possible.
In cases where there is more gas than is consumed in heating the
materials in the upper chamber such surplus gas is drawn off below
the top of the materials in the furnace, and it may thereafter be
utilised.
In place of forming the upper part of the furnace with an enlarged
chamber one or more chambers or flues leading into the upper part of
the furnace or cupola may be substituted.
When the materials are heated by the combustion of the gas and air
they are pushed into the smelting or melting chamber from time to time
in quantities as required.
The second part of this Invention has for its object to economise the
working of blast furnaces or cupolas by causing the materials to absorb
the heat from the escaping gases, and so render them more easily
condensed, as herein-after mentioned. This object is effected by raising a
the shaft of the blast furnace or cupola to a great height, and to prevent
the great burden of the materials in the blast furnace or cupola so
constructed from pressing too heavily on itself, and so hindering the
ascent of the blast, the upper part of the blast furnace or cupola is
divided by cross walls or partitions, or by an arch or a series of arches a
into compartments, each of which are or may be provided with a closing
bell or cover, or one bell or cover may be used for closing the whole.

page_text: The upper part of the improved blast furnaces or cupolas may also
be enabled to diminish the effect of the burden by a series of projections
built in or attached to the inside of the furnace or cupola, or the top
portion of the furnace or cupola may be made much narrower than
usual.
In order to further effect the cooling down of the gases issuing from
blast furnaces or cupolas so as to collect the tar, ammoniacal water, and
other condensible products the blast furnaces or cupolas are provided
with water chambers or scrubbers, filters, or washers, or condensers, in
or through which the gases are passed; or this object may be effected
by passing the ammoniacal water previously cooled down through the
gases, or passing the gases through the water so cooled down.
When necessary the gases may be assisted through the condensing or
purifying apparatus by means of a blowing or exhausting fan or its
equivalent. The gases being thus cooled and washed may be utilised
for heating or illuminating purposes, or if desired may be further
purified before being so used. The tar, oil, ammoniacal water or other
condensible products are drawn off and collected as required.
In cases where the products which pass off from the tops of blast
furnaces or cupolas are not worth condensing and collecting in the
manner herein-before described traps are placed in the exit flue, or the
gases are allowed to settle in a large chamber, from which the deposit
is taken out from time to time for utilisation. As in some cases it is
desirable to smelt, melt, or puddle metals in a chamber without contact
with solid fuel this object is effected by placing the fuel in compartments
and blowing air through it when ignited, conveying the gas so produced
to the smelting, melting, or puddling chamber (preferably at numerous
points), wherein it is burnt with air (preferably hot) forced or drawn in
at numerous points.

page_text: passing off from the materials, and thereby raising the materials in the
enlarged chamber to a very high temperature, and so facilitating the
smelting operations.
The same result may also be obtained by constructing the blast
furnace or cupola with an uniform outward taper or inclination from
the "boshes" upwards, so that the upper part of the blast furnace or
cupola is of larger capacity than the lower part, and owing to the
absence of the ledge or shelf (consequent upon the construction of an
enlarged upper chamber as herein-before described) the materials are
more exposed to the action of the hot gases.
In cases where more gas is supplied than is consumed in heating the
materials in the upper chamber or upper part of the blast furnace or
cupola such surplus gas is drawn off below the top of the materials in
the furnace.
In place of forming the upper part of the furnace with an enlarged
chamber one or more chambers or flues leading into the upper part of
the furnace or cupola may be substituted.
When the materials are heated by the combustion of the gas and air
they are pushed into the smelting or melting chamber as required.
The second part of my Invention has for its object to economise the
working of blast furnaces or cupolas by causing the materials to absorb
the heat from the escaping gases, thereby rendering the said gases more
casily condensed, as herein-after described. This object is effected by
raising the shaft of the blast furnace or cupola to a greater height, and
to prevent the great burden of the materials in the blast furnace or
cupola so constructed from pressing too heavily on itself, and thereby
hindering the ascent of the blast, the upper part of the blast
furnace or cupola is divided by cross walls or partitions, by arches,
or by a series of arches, cach of which is or may be provided with a
closing bell or cover, or one bell or cover may be used to close the
whole.

page_text: In order further to effect the cooling down of the gases issuing from
the blast furnaces or cupolas, and in order to collect the tar, ammoniacal
liquor, and other condensible products the blast furnaces or cupolas are
provided with water chambers or scrubbers, filters, washers, or con-
densers, over or through which the gases are passed; or this object may
be effected by passing the ammoniacal liquor previously cooled through
the gases or vice versa. The gases thus cooled and washed may be
utilized for heating or illuminating purposes, or if desired may be
further purified before being so used. The tar, oil, ammoniacal liquor
or other condensible products are drawn off and collected as required.
In cases where the products which pass off from the tops of blast
furnaces or cupolas are not worth condensing and collecting in the
manner herein-before described traps are placed in the exit flues, or the
gases may be allowed to settle in a large chamber, from whence the
deposit may from time to time be removed for utilization.
In some cases it is desirable to smelt, melt, or puddle metals without
bringing them into contact with solid fuel. This object is effected by
placing the solid fuel in compartments separate from the metal and
blowing air through it when ignited. The gas so produced is conveyed
to the smelting, melting, or puddling chamber. Air (preferably hot) is
also drawn or forced at numerous points into the smelting, melting, or
puddling chamber, where, meeting with the gas produced as herein-
before described, ignition takes place, and the smelting, melting, or
puddling operation is performed upon the metals contained in the
chamber herein-before described.
! And in order that my said Invention may be properly understood I
now proceed more particularly to set forth the system, mode, or manner
in or under which the same is or may be used or practically carried into
effect, reference being had to the annexed Sheet of Drawings and to the
letters and figures marked thereon, that is to say:—
Figure 1 on the annexed Sheet of Drawings is a side elevation of a
blast furnace constructed in accordance with the first part of my Inven-
tion; Figure 2 is a horizontal section of Figure 1 at the line a, b;
while Figure 3 is a vertical section at right angles to Figure 1. This
furnace is constructed so that the upper part thereof is of larger capacity
than the lower part, whereby a large bulk of material is contained in a
furnace of less than ordinary height. This object may either be gained

page_text: by constructing the furnace with an uniform outward taper or inclination
on the sides thereof, as shewn in full lines at Figure 3, or by forming an
cnlarged chamber at the upper part of the furnace, as shewn in dotted
lines at Figure 3. The materials are charged into the furnace through
the charging doors A from the charging platform B. Pipes C extend
along both sides of the upper part of the furnace, and by means of
twyers c these are put in connection with chambers D formed in the
sides of the furnace. Numerous small perforations connect the
chambers D with the interior of the furnace, so that when air (preferably
heated) is drawn or forced through the pipes C, and thence through the
twyers c into the chambers D, it is delivered into the furnace at numerous
points, as shewn more particularly at Figure 2. Combustion of the
gases escaping from the materials in the blast furnace is thus effected,
thereby producing great heat in the upper part of the furnace and so
heating the materials without igniting or consuming them, the waste
products of combustion passing off through the flue E, which is regulated
by a damper: Such portion of the combustible gases as is not required
to be consumed by contact with the air drawn or forced through the
pipes C is taken off from the furnace by the gas pipes F. The upper
O part of the furnace is covered by an arch or dome of fire-brick or other
refractory material.
Figure 4 is a side elevation, and Figure 5 a vertical section at right
angles to Figure 4 of a blast furnace constructed according to the second
part of my Invention, which consists in raising the shaft of the furnace
to a greater height than usual, so that the materials in the upper part
thereof absorb nearly the whole heat from the gases arising from the
combustion going on in the lower part of the furnace, whereby the
temperature of the materials is raised, and whereby the gases are cooled
and rendered more casily condensed. The shaft (though it may be
made parallel or nearly so) is preferably constructed with an inward
taper or inclination from the "boshes" upwards, as shewn on the
Drawings.
The upper part of the furnace is provided with a bell B and cone C
operated by an hydraulic cylinder D, and through which the materials
are charged to the furnace. To prevent the weight due to so high a
column of materials from pressing too heavily upon itself at its upper
part the furnace is constructed tapered, as shewn in the Drawings, so

page_text: blown through the twyers h promotes a slow combustion, and the
generation of gases in the compartments B, which issuing through the
flues or ports C into the melting, smelting, or puddling chamber A, are
there met by the air supplied by the pipes I. The gases and air on
meeting become ignited and burn, whereby the metal in the melting
chamber A is melted, smelted, or rendered fit for puddling. The
products of combustion in the chamber A pass off through the flues M,
and may thereafter be utilized for heating the air required for the
furnace or for other convenient purposes.
Having now described and particularly ascertained the nature of my
said Invention, and the system, mode, or manner in or under which the
same is or may be used or practically carried into effect, I would observe
in conclusion that what I consider to be novel and original, and there-
fore claim as the Invention secured to me by the herein-before in part
recited Letters Patent is,―
First. The construction of blast furnaces or cupolas with their upper
parts enlarged, or with an enlarged chamber or flue, or a series of
chambers or flues at the top for holding the materials before being
charged into the melting chamber of the blast furnace or cupola, and
the heating of the materials in the said chamber or chambers, flue or
flues, by the combustion of the gases ignited by air forced or drawn
thercinto, substantially as hercin-before described and shewn.
Second. The construction of blast furnaces or cupolas of increased
height, so that the heat of the escaping gases is utilized by being
imparted to the materials in the upper part of the furnaces, and the
temperature of the gases reduced; thereby facilitating their condensation,
as herein-before described and shewn.
Third. Providing blast furnaces with condensers, scrubbers, filters, or
washers for collecting the condensible portions of the gases and for
purifying the non-condensible products; also chambers for collecting
the products that come from the top of the blast furnaces or cupolas,
substantially as herein-before described and shewn.
Fourth. The construction of blast furnaces for smelting, melting, or
puddling operations with chambers for holding the fuel out of contact
with the metal in the smelting, melting, or puddling chambers, the gas
from the fuel being burnt with air forced or drawn in through numerous

page_text: small perforations, as distinguished from being introduced through large
openings, substantially as herein-before described and shewn.
In witness whereof, I, the said Henry Aitken, have hereunto
set my hand and scal, this Thirteenth day of August One
thousand eight hundred and seventy-four.
HENRY AITKEN. (L.S.)