IMPROVEMENTS IN FURNACES FOR HEATING THE BLAST FOR BLAST FURNACES
Year: 1865

page_text: LETTERS PATENT to Thomas Whitwell, of Stockton-on-Tees, in the
County of Durham, Ironmaster, for the Invention of "IMPROVEMENTS
IN FURNACES FOR HEATING THE BLAST FOR BLAST FURNACES."
Sealed the 4th May 1866, and dated the 10th November 1865.
PROVISIONAL SPECIFICATION left by the said Thomas Whitwell at
the Office of the Commissioners of Patents, with his Petition, on the
10th November 1865.
I, THOMAS WHITWELL, of Stockton-on-Tees, in the County of Durham,"
Ironmaster, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN FURNACES FOR HEATING THE BLAST FOR BLAST FURNACES," to
be as follows:-
This Invention has for its object improvements in furnaces for heating
the blast for blast furnaces. For these purposes two similar ovens or
heating chambers are employed which are alternately heated by burning
therein gas supplied from blast furnaces, and the blast to be heated is
alternately directed into and is caused to pass through these two ovens or
chambers. Each oven or heating chamber is enclosed by four upright
walls, and is divided by upright parallel partitions or walls into several
narrow compartments. These walls are formed of fire-brick, ganister, fire-
stone, or other suitable refractory material. The top and bottom of each
oven or chamber is formed similarly to the walls. The walls are alternately

page_text: constructed with openings at top and bottom, so that the blast in passing
through an oven or chamber passes alternately under and over the suc-
ceeding walls or partitions. Over the walls, which do not ascend to the
top of the chamber or oven, are openings for facilitating the cleansing.of
the surfaces of the walls from the dust deposited by the gas thereon, these
openings when the blast is passing through the oven or chamber, and also
when heating the chamber with gas, are covered by plugs of refractory
material, but the plugs are removed when the walls are being cleaned,
The exterior of the oven is covered with iron,, and the plugs above men-
tioned are attached to doors of iron. At the lower part of each oven or
chamber are other openings suitably closed, through which the dust
removed from the surface of the walls when cleaning the same is discharged,
and through which atmospheric air may be introduced to ignite the gas in
the chamber. At the opposite sides of each oven or stove are pipes with
suitable valves which are alternately used for supplying gas to, and for
allowing the products to pass off from each oven or chamber to the
chimney during the heating of the oven or chamber, and such pipes are
also used for conducting the blast into and from each oven or chamber,
but when the blast is passing through an oven or chamber it is caused to
flow in the opposite direction to that in which the gas has been previously
caused to flow through the oven or chamber when heating it, and this is
accomplished by the valves which are worked in such manner as to cause
the blast to enter at the side of the oven or chamber where it is
connected with the chimney, and to cause the heated blast to pass off by
the pipe which had been previously used as the gas supply pipe for
introducing the gas into the chamber or oven. If desired, the atmospheric
air may be supplied to each oven or chamber otherwise than by the
openings at the bottom of the oven or chamber.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the Said Thomas Whitwell in the Great Seal Patent Office on the
10th May 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
WHITWELL, of Stockton-on-Tees, in the County of Durham, Ironmaster,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Tenth day of November, in the year

page_text: 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 Thomas Whitwell, Her special licence that I,
the said Thomas Whitwell, my executors, administrators, and assigns, or
such others as I, the said Thomas Whitwell, 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 FOR HEATING THE BLAST
FOR BLAST FURNACES," upon the condition (amongst others) that I, the said
Thomas Whitwell, 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 Great 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 Thomas Whitwell, 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 thereof, that is to say :-
This Invention has for its object improvements in furnaces used for
heating the blast for blast furnaces. For these purposes two similar furnaces,
ovens, or heating chambers are employed, which are alternately heated by
burning therein gas supplied or emitted from blast furnaces daring the
process of smelting, and the blast to be heated is alternately directed into
and is caused to pass through these two furnaces, ovens, or chambers.
Each furnace, oven, or heating chamber is enclosed by four upright walls,
and is divided by upright parallel partitions or walls into several narrow
compartments. These walls are formed of fire-brick, ganister, fire-stone,
or other suitable refractory material. The top and bottom of each furnace,
oven, or chamber is formed similarly to the walls. The partition walls are
alternately constructed with openings at top and bottom, so that the burn-
ing gas and also the blast in passing through an oven or chamber passes
through each of the narrow compartments and alternately under and over
the partition walls in succession. And my improvements consist in forming
such furnaces, ovens, or heating chambers with such openings in their tops
and sides as herein-after mentioned for facilitating the cleansing of the
interior surfaces of their walls from the dust deposited by the gas
burnt

page_text: therein. For this purpose I form the top of each furnace, oven, or heating
chamber with an opening above each of the partition walls, which do not
ascend to the top, and I make the opening of a proper shape and dimen
sions to enable a workman to introduce a convenient instrument and use it
for the purpose of detaching the dust from the surfaces of the narrow
compartment at each side of the partition wall. These openings, when
the blast is passing through the furnace, oven, or chamber, and also when
burning gas is passing through it for the purpose of heating it, are covered
by plugs of refractory material, but the plugs are removed when the interior
surfaces of the walls are being cleaned. I prefer to cover the exterior of
the oven with iron, and to attach the plugs above mentioned to doors of
iron. At the lower part of each furnace, oven, or chamber I form other
openings of suitable shapes and dimensions through which the dust
detached from the interior surfaces of the walls when cleaning the furnaces
may be discharged. Through these openings atmospheric air may be
introduced to ignite the gas to be burnt in the chamber for heating it.
At the opposite sides of each furnace, oven, or chamber are introduced
pipes with suitable valves, the pipe on one side communicating with the
narrow compartment at that side, and the pipe at the other side commu-
nicating with the narrow compartment at such last-mentioned side. These
pipes are used for supplying gas to one side of each furnace, oven, or
chamber during the heating thereof by the burning gas, and for allowing
the products of the combustion of the gas to pass off from the opposite
side of the furnace, oven, or chamber to a chimney. Those pipes are also
used for conducting the blast to be heated into one side of the furnace,
oven, or chamber, and out of it at the opposite side thereof; but when the
blast is passing through a furnace, oven, or chamber it is caused to flow in
the opposite direction to that in which the gas has been previously caused
to flow through the furnace, oven, or chamber when heating it, and this is
accomplished by the valves, which are worked in such manner as to cause
the blast to enter at the side of the furnace, oven, or chamber where it is
connected with the chimney, and to cause the heated blast to pass off by
the pipe which had been previously used as the supply pipe for introducing
gas into the furnace, chamber, or oven. If desired, the atmospheric
air necessary for supporting the combustion of the gas may be supplied to
each furnace, oven, or chamber otherwise than by the openings at the
bottom of the furnace, oven, or chamber.
the
Having thus stated the nature of my said Invention, I will proceed
more fully to describe the manner of performing the same.

page_text: DESCRIPTION OF THE DRAWINGS.
Figures 1 and 2 show two side elevations of apparatus constructed and
combined according to my Invention; Figure 3 shows an end elevation of
one of the furnaces, chambers, or ovens; Figure 4 shows a transverse sec-
tion of one of the two furnaces or chambers which compose the complete
apparatus; and Figure 5 a plan of the two furnaces, chambers, or ovens,
one being shown in section. In each of these Figures the same letters of
reference are used to indicate the same parts.
The apparatus shown in the Drawings consist of two similar furnaces,
chambers, or ovens, which are by preference of a rectangular form, but
that form is not essential. The two furnaces, chambers, or ovens are of
like construction, and each is enclosed by four walls of fire-brick or other
suitable material (capable of bearing high a temperature), strengthened by
external iron plating. Each furnace, chamber, or oven is divided by
upright walls, which are constructed in such manner that the alternate
walls are open at top and bottom, so that the blast of air entering on one
side of one of the furnaces, chambers, or ovens near the bottom is by the
construction of the walls caused to ascend, then to descend, then to ascend,
and so on till the blast of air gets away near the bottom of the opposite
wall of the same furnace, chamber, or oven. At the top of each furnace,
chamber, or oven are iron doors K, K, which are lined with fire bricks, or
lumps L, L, which fit the openings in the tops of the chambers or ovens.
These openings in the tops of the furnaces, chambers, or ovens are formed
over the walls, which do not come to the top of the furnaces, chambers,
or ovens. By thus having openings over the shorter walls the surfaces of
the walls of the narrow compartment to the right hand, as well as those of
the narrow compartment to the left hand directly below the opening, can
be cleaned with facility. These openings, when the air blást is passing
through a furnace, oven, or chamber, are kept closed. In the arrangement
shown there are three of the shorter walls in each of the furnaces, cham-
bers, or ovens; but the number of shorter and higher walls used in a
furnace, oven, or chamber may be varied according to the extent of surface
over which it is desired the air blast shall pass. At the lower parts of the
walls which ascend to the tops of the furnaces, chambers, or ovens there
are openings for the passage of the air blast. Two furnaces, ovens, or
chambers are used in combination, in order to maintain a regular stream of
hot blast. Gas from a blast furnace is supplied to one furnace, chamber,
or oven to heat the same whilst the air blast is passing through the other
chamber or oven. And the arrangement of the passages and valves in

page_text: connection with the furnaces, ovens, or chambers is such that the air blast
passes through the furnaces, ovens, or chambers in the opposite direction
to that in which the gases from the blast furnace pass through the
furnaces, chambers, or ovens. The passages from the furnaces, chambers,
or ovens where the products of the combustion of the gases pass off are
during that time caused to be in communication with a chimney. By
these means the air blast is gradually heated as it ascends and descends
the compartments within either of the furnaces, chambers, or ovens, and
the air blast receives its greatest heat from the hottest parts of the walls
in the furnaces, chambers, or ovens immediately before leaving them.
The dust carried by the gas accumulates on the walls and requires to
be scraped or removed from time to time. The scraping or removal
from the walls is performed by proper tools introduced through the top
openings above described, and the dust is removed from the bottom of
each chamber or oven through the openings covered by the doors or
valves D, D, by means of rakes or other convenient tools. The gas from
a blast furnace is introduced by the pipe A, and passes either to the
one or the other of the two furnaces, chambers, or ovens; say, for in-
stance, the gas is introduced first into No. 1 furnace, chamber, or oven
through the valve B', the other valve B being closed, as also the blast
valve C¹. The gas is ignited by air supplied through the cleaning open-
ings D, protected from the heat by moveable perforated bricks N, N, by
which the heat of the gas burned in the compartments or spaces between
the walls in the furnace, chamber, or oven causes the walls to become
very highly heated. The products arising from the burning of the gases
pass off through the valve B² into the pipe A' and thence into the chimney.
The interior of No. 1 furnace, chamber, or oven is thus made ready to
receive the air blast to be heated. The supply of gas from the blast fur-
nace is then passed into the oven or chamber No. II. through the valve
B, the other valve B' being closed, as also the blast valve C, and the gas is
to be ignited by air supplied through the openings at D, and the burned
gases pass off by the valve B³ to the chimney. The air blast when the
furnace, chamber, or oven No. 1 has been heated is introduced by the
pipe J through the valve C3, the valve C being closed, and the air blast is
caused as before stated by the arrangement of the valves to pass through
the heated chamber in the opposite direction to that followed by the gas,
and the heated blast will pass off through the valve C¹ into the pipe J'.
So soon as the air blast ceases to be sufficiently heated it is shut off from
the furnace, chamber, or oven No. 1, and turned on through the furnace

page_text: or oamber No. II., which has become highly heated during the time that
the air blast has been passing through No. 1 furnace, chamber, or oven,
and the cold air is admitted by the pipe J and flows through the valve C³,
the valve C and also the gas valve B being closed. The heated'air blast
passes off by the valve C into the pipe J'. During the time that the air
blast is passing through the furnace, chamber, or oven No. II. the chamber
or oven No. 1 will be again heated, and thus may a continued highly heated
air blast be maintained. The gas pipes A, A¹, can be cleaned through
the openings closed by the valves D', D¹. In place of supplying air through
the cleaning openings D for the combustion of the gas, openings may be
made such as are indicated at M, M.
Having thus described the nature of my Invention, and the manner of
performing the same, I would have it understood that I claim, the construc-
tion of furnaces, ovens, or chambers for heating the blast for blast furnaces
with openings at the top capable of being closed by means of plugs or
doors, and also with openings at bottom of the sides thereof capable of
being closed by means of doors or valves, as herein described, for the
purpose of cleansing the interior of such furnaces, ovens, or chambers from
dust, as herein-before described,
In witness whereof, I, the said Thomas Whitwell, have hereunto set
my hand and seal, this Sixteenth day of April, in the year of our
Lord One thousand eight hundred and sixty-six.
THOMAS WHITWELL. (L.S.)