IMPROVEMENTS IN SUPPLYING HOT BLAST TO BLAST AND OTHER FURNACES, AND IN THE APPARATUS OR MEANS EMPLOYED THEREFOR
Year: 1872

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn
Fields, in the County of Middlesex, Gentleman, for the Invention of
"S IMPROVEMENTS IN SUPPLYING HOT BLAST TO BLAST AND OTHER FURNACES,
AND IN THE APPARATUS OR MEANS EMPLOYED THEREFOR."—A communication
from abroad by La Société Générale de Metallurgic Procédés
Ponsard, of Paris, in the Republic of France.
Sealed the 27th December 1872, and dated the 21st August 1872.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition,
on the 21st August 1872.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County
of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN SUPPLYING HOT BLAST TO BLAST AND OTHER
FURNACES, AND IN THE APPARATUS OR MEANS EMPLOYED THEREFOR," a com-
munication to me from abroad by La Société Générale de Metallurgie
Procédés Ponsard, of Paris, in the Republic of France, to be as follows:-
This Invention relates to a mode of heating the blast for blast and
other furnaces in which such a pressure of air is required as necessitates
-

page_text: the use of a blowing apparatus, and consists essentially in the application
and use for that purpose of the regenerator ponsard, described in the
Specification of my Patent No. 1624, A.D. 1870, in substitution for the
ordinary heating apparatus hitherto employed. This application admits
of a perfectly uniform heating of the blast and effects a considerable
the use of it drowing apparatus, and consists essentianty in the application
and use for that purpose of the regenerator ponsard, described in the
Specification of my Patent No. 1624, A.D. 1870, in substitution for the
ordinary heating apparatus hitherto employed. This application admits
of a perfectly uniform heating of the blast and effects a considerable
saving in the cost of construction of the apparatus employed.
The improved apparatus for heating the blast is composed of two
parts.
First. A large regenerator constructed on the principle set forth in the
Specification of my said Patent No. 1624, A.D. 1870.
Second. A combustion chamber for the waste gas from the furnace
situate at the upper part of the apparatus. The products of combustion
robbed of their heat pass off by a chimney.
The regenerator comprises two series of spaces; in the first scries
circulates the gas from the combustion chamber, in the second circulates
the blast to be heated, each space for air being situate between two
spaces for heated gas, and vice versa. Each of the chambers is provided
with obstructions for the purpose of retarding the current of the gas
through it, which obstructions, being composed of hollow bricks disposed
in the quincunx form communications between the various chambers
which increase still further the heating surface. The combustion
chamber before referred to situate at the top of the apparatus ensures
the complete combustion or ignition of the gas from the furnace before
it enters the regenerator below. On leaving this chamber the consumed
gases descend through openings for that purpose, finally escape into the
chimney at a low temperature.
The air or blast follows an opposite course; it enters the lower part of
the regenerator by a blast pipe, and after being distributed through the
numerous heating spaces in the regenerator it enters a metal conduit
lined with fire-brick, which conveys it to the blast or other furnace.
To prevent leakage of air in the apparatus the bricks composing such
apparatus are formed with grooved or sunk surfaces both at the vertical
and horizontal joints so that at each joint a double groove forming an
intermediate channel or chamber is obtained which in building the
regenerator is filled with fire-clay, and as this clay on the application
of heat becomes hardened it forms a species of key between the two
adjoining bricks at every joint, the bricks which cover the air chamber

page_text: or spaces at the top of the apparatus are prevented from being lifted by
thic pressure of the blast by means of vertical columns of fire-clay or
brick held down by springs bearing against transverse horizontal double
T girders.
SPECIFICATION in pursuance of the conditions of the Letters Patent,"
filed by the said John Henry Johnson in the. Great Seal Patent
Office on the 21st February 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-first day of August, in 'the
year of our Lord One thousand cight hundred and seventy-two, in tho
thirty-sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Henry Johnson, Her special
license that I, the said John Henry Johnson, my executors, adminis-
trators,, and assigns, or such others as I, the said John Henry Johnson,*
my exccutors, 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 SUPPLYING HOT BLAST TO BLAST AND OTHER FURNACES, AND' IN
THE APPARATUS OR MEANS EMPLOYED THEREFOR," a communication to me from
abroad by La Société Générale de Metallurgic Procédés Ponsard, of Paris,
in the Republic of France, upon the condition (amongst others) that I;
the said John Henry Johnson, my executors or administrators, 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 Scal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
•

page_text: and 4 are horizontal sections of the same taken respectively along the
lines I, J, K, L, and C, D, (Figures 1 and 2 respectively). Figure 5 is
a transverse section taken along the line M, N, (Figures 1 and 3) of
the flue conducting the hot air to the blast furnace. Figure 6 is a
horizontal section taken along the line S, T, U, V, (Figure 2) shewing
the arrival in the chimney of the products of combustion, and Figure 7
is a vertical section taken along the line O, P, (Figure 2) shewing the
mode of heating the air required for the combustion of the gases in the
external walls of the apparatus. .
The "ponsard regenerator" shewn in Figures 1, 2, and 3 comprises
two series of spaces. The gases proceeding from the combustion
chamber circulate in the first series a, and the air to be heated passes
through the second series b so that each vertical air space is always com-
prised between two similar spaces of liot gases, and vice versa. Each
of the chambers is moreover provided with baffles formed of solid or
hollow bricks and disposed, quincuncially so as to retard the motion of
the gases which are to circulate therein. In my Drawing the balles
formed in the air passages are of solid bricks, and those which cross the
smoke passages are of hollow bricks, in order to place the vertical
chambers in which the heated air rises into the apparatus in communi-
cation with one another by which the heating surface is considerably.
increased.
The apparatus thus possesses great heating power in a relatively small
compass. At its upper part there is disposed a chamber c, intended for
the complete combustion of the gases, which descend thence into the
spaces a in order to escape into the chimney d (Figure 6) at a low
temperature. The air takes the reverse direction, as shown in Figures 1, 2,
and 3, it arrives by the transverse pipe e and enters through tho
branches into the lower part of the apparatus where it is distributed
in the intermediate compartments b, and is collected on leaving the
regenerator in a collecting tube 7 (Figure 5) formed of a sheet metal
casing lined in the interior with bricks of fire-clay, which tube conveys
it to the blast furnace.
In order to prevent any possibility of the escape or filtration of the
air, which is at a pressure of from 6 to 8 inches of mercury, from the
air chambers to the chambers intended for the burnt gases, the following
arrangement is employed:-The whole of the bricks are provided at all
their vertical and horizontal joints with a groove of a suitable depth and

page_text: width, whence it follows that in the juxtaposition of two horizontal
bricks, or in superposing two vertical bricks, there will be at cach joint
a double groove forming a channel between the two bricks, this channel
is filled at the time of the construction of the regenerator with fire-clay,
which after being subjected to heat becomes a species of key, uniting
each brick to the adjoining horizontal and vertical bricks. By this
means the bricks cannot possibly be displaced, excepting those which
close the air chambers on the top of the apparatus, which might be
raised by the pressure of the blast, but those bricks are maintained or
pressed down by walls (Figures 1, 2, and 4) of refractory materials
of a sufficient height to ensure their weight, balancing the internal
pressure of the blast whilst admitting of the expansion of the system of
brickwork.
The refractory brickwork and that of non-refractory bricks surround-
ing the regenerator is of sufficient thickness to prevent too great a loss
of heat, and the apparatus is in addition entirely encased in a sheet
metal casing i strengthened with double T iron so as to prevent any
distortion of the brickwork by reason of the internal pressure of the
blast which is injected therein by the blast engine..
k
The air required for the combustion of the gases of the furnace is :
itself heated by passing into the sides of the apparatus between two walls
united by bricks arranged quincuncially (Figures 2, 3, and 7) which
increase the heating surface and ensure the strength of the structure,
it enters the apparatus through apertures; formed near the base of the
regenerator (Figure 2) and after having circulated in the spaces arrives a
at a series of apertures or burners m disposed on the right and on the
left of the chamber c, and to which the combustible gases arriving by
the tubes n are also directed so that these gases and the air meeting at
a right angle and in alternate small currents are perfectly mixed at the
same instant which ensures perfect combustion.
In order the more fully to explain the mode of constructing this
apparatus I have shown in Sheet 2 the various types of bricks employed
therein.
Figures 1, 2, and 3 (Sheet 2) shew in clevation and transverse section
an ordinary hollow brick provided with recesses on all its junction surfaces.
Figures 4, 5, and 6 shew in elevation and vertical section a prism
forming a solid brick provided with its recesses. -

page_text: Figures 7, 8, and 9 shew in elevation and transverse section a hollow
double brick provided with its recesses.
Figures 10 and 11 shew in elevation a solid brick provided with its
recesses.
Figures 12 and 13 show in elevation a solid half brick provided with
its recesses.
Figures 14 and 15 shew in elevation a solid brick provided with its
recesses..
Figures 16 and 17 shew in clevation a solid double elbow brick pro-
vided with its recesses.
Figures 18, 19, and 20, show in elevation a single T solid half brick
provided with its recesses.
Figures 21 and 22 shew in clevation a solid double elbow brick
provided with its recesses.
Figures 23 and 24 shew a prismatic block composed of clay without
recesses.
Figures 25 and 26 shew a block composed of clay with its two junction
pieces, but without recesses.
Figures 27, 28, and 29, shew a block composed of clay with a junction
piece and recesses.
Figures 30, 31, and 32, shew a block composed of clay with junction
picce and recesses.
";
Figures 33, 34, and 35, shew a block composed of clay having two
junction pieces and recesses.
It will be observed that the junction faces of these bricks are pro-
vided as before stated with recesses. intended to receive the mortar
which ensures the tightness of the joint thus formed and to prevent its
being expelled by the pressure of the blast in the apparatus.
The detail Drawings of these various bricks illustrate their form so
clearly as to render any detail description of each of them unnecessary.
Having now described and particularly ascertained the nature of the
said. Invention, and the manner in which the same is or may be used
or carried into effect, I would observe in conclusion that what I consider
to be novel and original, and therefore claim as the Invention secured
to me by the herein-before in part recited Letters Patent is,—
"

page_text: First. The peculiar process of and apparatus for blowing hot air into
blast and other furnaces as herein-before described.
Second. The application and use of what is known as the "ponsard
regenerator" to and in the heating of the blast for blast and other
furnaces, substantially as herein-before described and illustrated by the i
Drawings annexed.
Third. The peculiar construction of bricks to be employed in building.
-the blast heating apparatus, as herein-before described and illustrated
on Sheet 2 of the Drawings annexed.
In witness whereof, I, the said John Henry Johnson, have to this 1
my Specification set my hand and seal, this Twentieth day of
February One thousand cight hundred and seventy-three.