IMPROVE- MENTS IN BLAST FURNACES
Year: 1871

page_text: LETTERS PATENT to Andrew Barclay, of Kilmarnock, in the County
of Ayr, North Britain, Engineer, for the Invention of "IMPROVE-
MENTS IN BLAST FURNACES."
Scaled the 21st April 1871, and dated the 16th February 1871.
PROVISIONAL SPECIFICATION left by the said Andrew Barclay at the
Office of the Commissioners of Patents, with his Petition, on the
16th February 1871.
I, ANDREW BARCLAY, of Kilmarnock, in the County of Ayr, North
Britain, Engineer, do hereby declare the nature of the said Invention of
"IMPROVEMENTS IN BLAST FURNACES," to be as follows, that is to say:
-
This Invention has for its object the saving of fuel for heating and
coking the materials charged into open or closed topped blast furnaces,
or in furnaces which are partly open and partly closed at the top; and it
consists in forming a series of openings or an annular flue in the upper
part of the furnace from which pipes or passages lead to lower levels of
the furnace. Through these pipes or passages a portion of the gases

page_text: escaping from the upper part of the charge is drawn and introduced to
the charge in a burning state at the lower levels, where the pipes or
passages re-enter the furnace. The drawing off of the gases is effected
by a jet or jets of atmospheric air, which also supply the oxygen by
which the gases are ignited; or in place of a jet or jets of air the gases
may be drawn off and introduced by a fan or other forcing and exhausting
apparatus, and the air necessary for their combustion admitted by other
means. Or in place of taking off the gases at high levels and introducing
them at lower levels this may be reversed, that is to say, the gases may
be taken off at low levels of the furnace and introduced at higher levels
through suitable channels, pipes, or passages.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Andrew Barclay in the Great Seal Patent Office on
the 16th August 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ANDREW
BARCLAY, of Kilmarnock, in the County of Ayr, North Britain, Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of February, in the year
of our Lord One thousand eight hundred and seventy-one, in the 35th
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Andrew Barclay, Her special license that I,
the said Andrew Barclay, my executors, administrators, and assigns, or
such others as I, the said Andrew Barclay, my executors, administrators,
or 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 BLAST FURNACES,"
upon the condition (amongst others) that I, the said Andrew Barclay,
by an instrument in writing under my hand and seal, 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.

page_text: NOW KNOW YE, that I, the said Andrew Barclay, do hereby declare
the nature of my 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 accompanying
Drawings, and to the letters and figures marked thereon, that is to
:—
say:-
My said Invention has for its object the saving of fuel for heating and
coking the materials charged into open or closed topped blast furnaces,
or in furnaces which are partly open and partly closed at the top; and it
consists in forming a series of openings or an annular flue in the upper
part of the furnace, from which pipes or passages lead to lower levels of
the furnace. Through these pipes or passages a portion of the gases
escaping from the upper part of the charge is drawn, and introduced to
the charge in a burning state at the lower levels where the pipes or
passages re-enter the furnace. The drawing off of the gases is effected
by a jet or jets of atmospheric air, which also supply the oxygen by
which the gases are ignited; or in place of a jet or jets of air the gases
may be drawn off and introduced by a fan or other forcing and ex-
hausting apparatus, and the air necessary for their combustion admitted
by other means. Or in place of taking off the gases at high levels and
introducing them at lower levels this may be reversed, that is to say, the
gases may be taken off at low levels of the furnace, and introduced at
higher levels through suitable channels, pipes, or passages.
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, that is to say :-
the
Upon Sheet 1 of the Drawings hereunto appended, Figure 1 is a
vertical section upon the line E, F, Figures 2 and 3, of a blast furnace
constructed according to one arrangement of my Invention, whilst
Figures 2 and 3 are respectively horizontal sections of the same upon
lines A, B, and C, D, Figure 1. The same letters of reference mark
the same or corresponding parts upon the different Figures in which
they occur.
Under the arrangement of blast furnace now under reference my
improvements consist in providing an annular flue A, in the upper part
of the masonry B, and arranged concentric with the shaft C of the
furnace, between which and the said annular flue A communication is

page_text: provided by a series of flues or radial openings D, and by somewhat
similar flues or openings E, formed in the outer portion thereof, com-
mmunication is also made with a series of vertical pipes a, arranged
around the exterior of the furnace, their upper extremities being attached
to the flues or openings E by means of branches 6, whilst the lower
extremities of the pipes a are attached and placed in open communi-
cation with another deep annular flue F, also formed in the masonry B
of the furnace, and arranged concentric with the hollow shaft C thereof.
Between the deep annular flue F, and the internal chamber C
communication is effected by a numerous series of openings c formed
in the wall B. The divisions d which separate the openings c from
each other are of fire-brick or other suitable refractory material and
formed with their outer surfaces bevilled inwards in an upward direction
as shewn at Figure 1, whilst their inner surfaces are formed with both
their upper and lower corners bevilled off as similarly shewn at Figure 1.
The object to be achieved by so shaping these divisions is herein-after
set forth.
The upper and lower extremities of the deep annular flue F, are
respectively in open communication with a series of small flues or
openings G and H, preferably corresponding in number to the number
of the vertical pipes a, the mouths of which are furnished with hinged
doors e and f respectively. At the lower extremity of the upper
annular flue A, a series of short flues or openings I are also situated
passing outwards therefrom to the outer surface of the furnace B, their
mouths are also provided with doors g, as shewn at Figure 1. To the
upper extremities of the vertical pipes a pipes h are attached which are
provided with tapered nozzles or jet pipes i, each of which extends down
into each of the said vertical pipes a, and terminating at or near a
contracted throat a¹ formed therein, as shewn at Figure 1, Sheet 1. To
the horizontal member of each of the pipes h a stop cock k is attached,
which is in communication with a vertical pipe 7, extending downwards
therefrom, and having its lower end connected to a larger pipe m,
arranged by preference in the form of a concentric ring around the
furnace, as shewn. At a short distance above the pipe m a short
horizontal branch pipe n, is secured to each of the vertical pipes l, each
of which is provided with a stop-cock o in communication with a nozzle
or jet p, passing into each of the said pipes a, and directed horizontally
towards the deep annular flue F, as more particularly shewn at
Figure 1.

page_text: Having now described in detail one arrangement of the various
structural features constituting my improvements in blast furnaces, I
now proceed to set forth the manner wherein they are employed in
practice in the manner following:-When the furnace is in operation a
portion of the gases escaping from the upper part of the charge is drawn
outwards through the openings or flues D and E, then downwards
through the vertical pipes a, by means of jets of atmospheric air
escaping from the nozzles or jet pipes i. The velocity and quantity of
these jets of air are regulated to a degree sufficient to impart direction
to the course of the gases without igniting them, which is not effected
until they arrive at the lower extremities of the pipes a, at which
position the gases are brought into contact with other jets of air rushing
through the horizontal nozzles or jet pipes P, after which they enter the
annular flue F, when they become ignited, and thence passing through
the series of openings c they impart the heat due to their incandesence
to the materials contained therein, and thus become effectual in inten-
sifying the temperature of the charge. It is to be understood that the
quantity of air admitted by the jets is preferably sufficient to burn the
In this
gas, thus producing a neutral flame to act upon the materials.
manner as there is no exess of oxygen admitted the materials are raised
to a higher temperature without being oxidised, or by reducing the
quantity of air admitted the gas may be forced in, carrying carbon in
excess, which aiding in the reduction of the oxides of iron in the charge
effects a more thorough carbonization of the iron. In passing from the
annular flue F into the interior of the furnace the burning gases are
directed upwards in the desired course by means of the bevil faces formed
upon the outer surfaces, and the lower corners of the inner surfaces of
the divisions d, which separate the openings c, through which they pass,
whilst by means of the bevil face formed upon the upper corner of the
inner surface of the said divisions d the materials are less obstructed in
their descent through the furnace. Any dust, ashes, or pieces of the
iron making materials which may fall into either of these annular flues A.
or F may be removed when necessary through the several flue doors e, f,
and g, whilst another object for which the said doors e, f, and g, are
provided is to act as safety valves in the event of an explosion.
Upon Sheet 2 of the Drawings hereunto appended, Figure 1 is a
vertical section upon the line A, B, (Figures 2 and 3,) Figure 2 is a top
plan, and Figure 3 a horizontal section upon the line C, D, Figure 1,

page_text: shewing another modification of my improved blast furnace, and as the
arrangement and construction thereof is to some extent similar to the
arrangement herein-before set forth and illustrated upon Sheet 1 of the
accompanying Drawings I shall only further specify those parts wherein
it differs therefrom.
Under this modification of my Invention, the upper portion of the
furnace is divided into four or other number of separate charging
chamber A', four only being shewn at Figures 1 and 3, each of the
said chambers A¹ being furnished with a separate charging cone B¹, as
shewn at Figures 1 and 2. In the centre of this upper part of the
furnace a central vertical flue c¹ is formed from which other
flues r, µª³, 1º, 2º³, diverge radiating outwards and in open communication
with the lower annular flue F. Between the chambers A¹ and the
radiating flues 1, 71, 72, 73, communication is effected by means of
openings formed in the divisions L, as shewn at Figures 1 and 3,
whilst between the lower annular flue F and the chambers A¹ com-
munication is effected by means of the openings c, similar to those shewn
and described under the foregoing modification.
When this furnace is in operation the gases which are drawn off from
the upper part of the charge through the openings D and E, and thence
down through the vertical pipes a¹ into the lower annular flue F, in the
manner herein-before set forth with reference to the foregoing modi-
fication pass in part from the said annular flue F into the central flue C',
through the radiating flues r, 71, 72, 73, and thence through the
openings 8 into the chambers A', thereby imparting a higher degree of
temperature to the charge contained therein, whilst the remaining part
of the said burning gases which does not enter the central flue c', nor
radiating flues 7, 71, 72, 73, passes from the annular flue F into the
chambers A¹ through the openings c, in the manner herein-before
described with reference to the first arrangement.
Upon Sheet 3 of the Drawings hereunto appended is shewn in vertical
section a somewhat different arrangement of my improvements in blast
furnaces. This arrangement differs from the former modifications in so
far that the annular flue Fand the openings c through which the burning
gases are returned to the charge, are situated at a greater distance down-
wards from the top of the charge than obtains under the preceding
arrangements, and also in that, at that side of the Drawing marked A,
Figure 3, a rotary fan R is situated by means of which a portion of the

page_text: gases escaping from the top of the charge may be drawn off through
the openings D', and suction pipe E', and discharged downwards through
the discharge pipe F" to the heaters, to be there burned and employed
in heating the blast. At the opposite side of the furnace marked B,
another rotary fan S is situated with its suction pipe a², and discharge
pipe a³, respectively connected to the upper and lower pipes a, and cach
of the series of the said pipes a surrounding the furnace may be pro-
vided with the rotary fan S, to be employed in lieu of or in combination
with jets of atmospheric air admitted through the nozzles or jet pipes i,
to aid in drawing off a portion of the gases from the top of the charge
and directing them downwards to be ignited and readmitted to the
charge at a lower level, as in the foregoing modifications. In both the
fans R and S, the suction pipes E¹ and a², respectively are connected to
the eye or centre of the fan box so that the gases are drawn in at the
centre and discharged at the circumference of the box through the
respective discharge pipes F1 and a³.
It is to be understood that besides the three arrangements of my
improved blast furnace shewn upon the Sheets of Drawings appended,
there are other modifications under which my Invention may be carried
out in practice, for example, the annular flues A and F may be dispensed
with and a series of radial openings communicating with the upper and
lower ends of the pipes a may be adopted, and in place of taking the
gases from the upper part of the furnace and introducing them at a
lower level they may be taken from a lower and introduced at a higher
level, and either of the arrangements herein set forth may be repeated
at two or more levels in the height of the furnace.
It is further to be understood that although the Drawings illustrate my
Invention as applied to close top blast furnaces, that it may be also used
with open or partly open and partly closed top furnaces, such as are
used in smelting certain hæmatite ores, and in place of using jets of air
or a fan in combination with one or more jets of air as herein-before
described, one or more than two jets of air and one or more fans with
or without jets of air combined may be used for drawing off and forcing
in the gases.
Having now described 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

page_text: the
what I consider novel and original, and therefore claim as
Invention secured to me by the herein-before in part recited Letters
Patent is,―
First. The arrangement and construction of blast furnaces herein-before
described and shewn upon the three appended Sheets of Drawings or any 5
mere modification thereof.
Second. Drawing off and reintroducing the gases admixed with
atmospheric air, so as to burn them and to act upon all the materials
constituting the charge, substantially as herein-before described.
In witness whereof, I, the said Andrew Barclay, have here- 1
unto set my hand and seal, this Fourteenth day of August,
One thousand eight hundred and seventy-one.
ANDREW BARCLAY. (L.S.)