Improvements in Blast Furnaces and in Gas Producers and Tuyerės connected therewith.
Year: 1889

page_text: Date of Application, 4th June, 1889
Complete Specification Left, 4th Mar., 1890-Accepted, 31st May, 1890
PROVISIONAL SPECIFICATION.
Improvements in Blast Furnaces and in Gas Producers and Tuyerės
connected therewith.
I, JOHN GILL, of 2 Heriot Row Edinburgh, in the County of Midlothian,
Gentleman, do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in blast furnaces for the smelting of ores,
minerals, metals and other materials and in gas producers and tuyeres connected
therewith.
The blast furnace will be so arranged that it will be closed at the top and have a
cup and cone or other suitable arrangement for charging ore and fuel. Reductive
gases especially hydrogen and carbon oxide, will be prepared by a gas producing
furnace hereinafter described, and will be admitted or forced at a suitable temperature
into the blast furnace near the top and will descend through the ores and fuel in the
upper part of the furnace, and the whole or part of the descending gases will then be
drawn off through an opening or series of openings around the furnace and will be
conducted down the outside of the furnace to the tuyeres near the bottom. The
tuyeres will each consist of an outer and inner tuyere with an annular ring or space
between them. A pressure air blast will be forced through the inner tuyere into the
blast furnace, and the inflammable gases brought down from the upper part of the
furnace, will occupy the annular ring or space between each inner and outer tuyere,
and the nozzle of the outer tuyere will project beyond the nozzle of the inner tuyère
and be so formed that the pressure air blast passing through the inner tuyere will
draw or force into the furnace a supply of the inflammable gases. The air blast and
those inflammable gases will mix and ignite inside the furnace, and the burning of
them will intensify the heat, increase the fusing power and quicken the action of the
furnace, and enable it to be worked with less fuel and with other advantages. The
supply of air blast and of gases admitted by the tuyeres will be regulated or controlled
by means of stop cocks or valves or similar appliances on the pipes or conduits
conveying them to the tuyeres. The air blast may be cold or hot, but hot blast will
be preferred especially in large furnaces.
The waste gases or products of combustion will ascend from the zone of fusion
through the materials in the furnace and will pass out by an opening or series of
openings around the furnace at a height some distance under the level of the point
where the gases in the upper part of the furnace are taken off. The waste gases and
products of combustion after passing out of the furnace, as above mentioned, will
enter a chamber immediately outside the furnace, in which chamber there will be a
gas producing furnace, the top of which may be on a level with the top of the blast
furnace and will be closed in like manner by a cup and cone or similar arrangement
for charging it with fuel. The waste gases will surround the gas producing furnace
and give up to it part of their sensible heat. The heat of the waste gases will also be
used for heating the air blast and for raising and superheating steam. Those gases may
pass off, partly or wholly by a chimney, or partly or wholly by a down comer, and
they may also be burned with the addition of air blast, for heating the air blast and
raising and superheating steam or for heating a reverberating furnace, or for other
purposes.
The gas producing furnace will be closed at the top and will have a cup‘and cone
or other similar arrangement on the top for charging the fuel into it. It will have an
opening in it whereby the gases produced therein will pass off by a conduit or pipe and
enter the blast furnace by one or more openings near the top. Such opening in the
gas producing furnace will preferably be near the bottom. There will be tuyeres for
the admission of air blast at various heights or at all events near the bottom and also

page_text: at some distance under the level of the top of the fuel in the furnace. Each tuyere
will be capable of being shut off by means of a stop-cock. When the fuel in the gas
producing furnace is kindled and brought to a red heat by means of the air blast
through the tuyeres at the bottom, the air blast will then be shut off from those
tuyeres and turned on by the upper tuyeres and then the products of combustion will
pass downwards through the red hot fuel and will pass out by the opening near the
bottom above mentioned and enter the blast furnace near the top as already stated.
As the only outlet for the gases produced in the gas producing furnace will be by the
opening leading into the blast furnace those gases will be under sufficient pressure to
enable them to force their way down through the materials in the upper part of the
blast furnace. Sufficient air blast will be admitted to keep the fuel under the tuyeres
in the gas producing furnace at a bright red heat and superheated steam will be
admitted a short distance under the level of the upper tuyeres. The result will be a
continuous conversion of the superheated steam into water gas consisting of hydrogen
and carbon oxide. In some cases the heat of the waste gases issuing from the blast
furnace will be sufficient to keep the fuel within the gas producing furnace, at a
sufficient heat for the continuous formation of the requisite quantity of water gas
from superheated steam in which case the air blast for the gas producing furnace will
be shut off. The quantity of gas to be produced by the gas producing furnace can
be regulated as required by admitting more or less air blast and more or less super-
heated steam, and the temperature of the gases produced can also be regulated in like
manner. Coke, coal, slack, dross. or any kind of fuel may be used both in the gas
producing furnace and also in the blast furnace. Either hot or cold air blast may be
used for the gas producing furnace, but hot blast will be preferred. At the bottom of
the gas producing furnace the ashes will be drawn off by a revolving screw or similar
means.
The reductive gases formed by the gas producing furnace and entering the blast
furnace near the top at a proper temperature will heat up the contents of the upper
part of the blast furnace to the requisite temperature and will distil the volatile
portions of the fuel therein, coke any raw coal or fuel that may be used therein, turn
the moisture in the ores and fuel into water gas and carry down all the gases formed
therethrough the ores and fuel in the upper part of the furnace which gases containing
a large proportion of hydrogen and carbon oxide and being kept at a suitable
temperature by the regulation of the heat in the gas producing furnace, will have a
powerful effect in preparing and reducing the ores. The admission of those gases
from the gas producing furnace as described will enable the blast furnace to be
charged with less than the usual amount of fuel and to he worked with coke, coal,
wood or other, raw fuel and so that all the volatile portions of such fuel will be
utilised in the furnace, in the first place in preparing and reducing the ores, and
secondly for increasing and intensifying the fusing power of the furnace.
The arrangements described will have great advantages also in enabling small
concentrates and the dust of ores to be smelted without the loss, which frequently
takes place by the dust of the ores and fuel being blown out at the top. Any dust of:
ores escaping from the blast furnace as above described can be deposited in a catch
pool and made to flow into the hopper at the top of the furnace.
The arrangements described will also afford facilities for eliminating impurities
from ores &c. in the upper part of the blast furnace before the ores reach the zone of
fusion. In such cases the reductive gases admitted near the top of the blast furnace
will be allowed to descend and to leave the furnace along with the waste gases arising
from the zone of fusion, without any portion of them being drawn off and burnt at
the tuyeres, but a supply of the reductive inflammable gases may be taken direct
from the gas producing furnace to the tuyeres at the bottom of the blast furnace
without passing through the upper part of the blast furnace. In furnaces for
smelting such ores &c. where, it is desirable to prevent impurities therein from
entering the regulus or metal, it may be desirable to have the outlet for the products
of combustion at a very short distance above the zone of fusion and to have the upper
part of the furnace above such outlet made higher,

page_text: It
may be desired in some cases for the sake of simplicity to work the blast furnace
without bringing down to the tuyeres any inflammable gases in which cases that part
of the arrangement can be left out.
By the arrangements described the heat in the upper as well as in the lower part
of the blast furnace will be under the control of the furnace man. He can increase
it or diminish it at pleasure either in the lower or upper part of the furnace, and as
the reductive gases necessary in the upper part of the furnace can be supplied in
sufficient quantity from the gas producing furnace and gaseous fuel can also be
obtained at the zone of fusion in sufficient quantity to produce the heat necessary
there, the fuel to be mixed with the ores and charged into the blast furnace need not
be more or much more than is required for the chemical reactions in the blast
furnace. The fuel used both in the gas producing furnace and also in the blast
furnace will be consumed, especially when the waste gases issuing from the
blast furnace are burnt for heating air blast, raising and superheating steam, or for
heating a reverberatory furnace, so that the entire heat which the fuel is capable of
producing will be developed and utilized. In any case the fuel can be so consumed
that very little of its heating power will be lost, and there will also be much additional
reducing and fusing power got from the hydrogen brought into the furnace. The
use of hydrogen in the blast furnace as being one of the most effective reductive and
heating agents known, will be of great importance and value and the arrangements
described will enable it to be applied with great advantages.
Dated this Fourth day of June 1889.
JOHN GILL.
Per W. H. Beck,
115, Cannon Street, London, E.C., Agent.
COMPLETE SPECIFICATION.
Improvements in Blast Furnaces and in Gas Producers and Tuyeres
connected therewith.
I, JOHN GILL, of No. 2 Heriot Row, Edinburgh, in the County of. Midlothian,
Gentleman, do hereby declare the nature of this 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 two sheets of
Drawings and to the letters and Figures marked thereon that is to say :-.
This invention relates to improvements in blast furnaces for the smelting of ores,
minerals, metals, and other materials and in gas producers and tuyeres connected
therewith.
The blast furnace is to be closed at the top and to have the usual cup and cone
or other suitable arrangement for charging ore and fuel. Reductive gases, especially
hydrogen and carbon oxide, may be prepared by a gas producing furnace as herein-
after described, and are to be admitted or forced at a suitable temperature into the
blast furnace near the top, whence they descend through the ores and fuel in the
upper part of the furnace, and the whole or part of the descending gases are then
drawn off through an opening or series of openings around the furnace and are
conducted down to the tuyeres near the bottom. The tuyeres each consist of an
outer and inner tuyere with an annular ring or space between them. A pressure
air blast is forced through the inner tuyere into the blast furnace and the inflam-
mable gases brought down from the upper part of the furnace, enter the annular
ring or space between each inner and outer tuyere, and the nozzle of the outer
tuyere projects beyond the nozzle of the inner tuyere and is so formed that the
pressure air blast, passing through the inner tuyere, draws or forces into the
furnace, along with itself, a supply of the said inflammable gases. The air blast
and those inflammable gases mix and ignite inside the furnace, and their combus-
tion intensifies the heat, increases the fusing power, quickens the action of the
furnace, and enables it to be worked with less fuel, less air blast and with other
و

page_text: advantages. The supply of air blast and of gases admitted by the tuyeres may be
regulated or controlled by means of stop-cocks or valves or similar appliances on
tlie pipes or conduits. conveying them to the tuyeres. The air blast may be cold
or lot, but hot blast is preferable, especially in large furnaces.
The waste gases or products of combustion ascend from the zone of fusion
through the materials in the furnace and pass out by an opening or series of
openings around the furnace at a height some distance below the point where the
gases in the upper part of the furnace are taken off. The waste gases and
products of combustion, after passing out of the furnace as above mentioned, enter
a chamber immediately outside the furnace in which chamber there is or may be
placed a gas producing furnace closed at top by a cup and cone or other suitable
arrangement for charging it with fuel. The waste gases surround the gas pro-
ducing furnace and give up to it part of their sensible heat. The gas producing
furnace may be made of cast metal or other suitable material. The heat of the
waste gases may also be used for heating the air blast and for raising and super-
heating steam. Those gases may pass off partly or wholly by a chimney or partly
or wholly by a down-comer. Part may go by a down-comer and be used for
heating the air blast or for raising steam or for other purposes, and only part
may enter the chamber in which the gas producing furnace is placed and may
there be burned with the addition of air blast to increase the heat of that chamber.
The gas producing furnace has an opening in it whereby the gases produced
therein pass off by a conduit or pipe and enter the blast furnace by one or more
openings near the top. Such opening in the gas producing furnace is preferably
placed near the bottom. Tuyeres for the admission of air blast are placed at
various heights or at all events near the bottom of the gas producing furnace and
also at some distance under the level of the top of the fuel in the said furnace.
In some
Each tuyere can be shut off by means of a stop-cock when the fuel in the gas
producing furnace is kindled and brought to a red heat by means of the air blast
through the tuyeres at the bottom, the air blast is then shut off from those tuyeres
and turned on by the upper tuyeres and then the products of combustion pass down-
wards through the red hot fuel and out by the opening near the bottom above
mentioned, and enter the blast furnace near the top as already stated. As the only
outlet for the gases produced in the gas producing furnace is by the opening leading
into the blast furnace, those gases are under sufficient pressure to enable them. to
force their way down through the materials in the upper part of the blast furnace.
Sufficient air blast is admitted to keep the fuel under the tuyeres in the gas producing
furnace at a bright red heat and superheated steam in limited quantity is admitted
a short distance under the level of the upper tuyeres. The result is a continuous
conversion of the superheated steam into hydrogen and carbon-oxide.
cases the heat of the waste gases issuing from the blast furnace may be sufficient to
keep the fuel within the gas producing furnace at a sufficient heat, for the continuous
formation of the requisite quantity of gases from superheated steam, in which case
the air blast for the gas producing furnace may be shut off. The gas producing
furnace may also be worked with air blast and without the admission of any steam.
The quantity of gas to be produced by the gas producing furnace can be regulated
as required by admitting more or less air blast and more or less superheated
steam and the temperature of the gases produced can also be regulated in like
manner. Coke, coal, slack, dross or any kind of fuel may be used both in the
gas producing furnace and also in the blast furnace. Either hot or cold air blast
may be used for the gas producing furnace, but bot blast is preferred. At
the bottom of the gas producing furnace the ashes may be drawn off by a revolving
screw or other suitable means. The chamber in which the gas producing furnace is
placed can also be used, if desired, for placing therein a coil of pipe for heating the
air blast.
The reductive gases formed by the gas producing furnace and entering the blast
furnace near the top at a proper temperature, heat up the contents of the upper part
of the blast furnace to the requisite temperature and distil the volatile portions of the

page_text: coke, coal or any raw fuel that may be used therein, turn the moisture in the ores and
fuel into gases, and carry down all the gases formed there through the ores and fuel
in the upper part of the furnace, which gases, containing hydrogen and carbon-oxide,
and being kept at a suitable temperature by the regulation of the heat in the gas
producing furnace, have a powerful effect in preparing and reducing the ores. The
admission.of those gases from the gas producing furnace, and their combustion at the
tuyeres as above described, enable the blast furnace to be worked with less than the
usual amount of air blast, and to be charged with less than the usual amount of fuel,
and to be worked with coke, coal, wood or other raw fuel, and so that all the volatile
portions of such fuel will be utilised in the furnace in the first place, in reducing.
the ores, and secondly for increasing and intensifying the fusing power of the
furnace.
In some instances it may be desired to dispense with the gas producing furnace
but to adopt the drawing down to the tuyeres of the gases in the upper part of the
furnace, and in such cases a supply of hot gases for the top of the furnace may be got
by making an opening a few feet above the tuyeres and conducting the gases issuing
therefrom by a conduit to the top of the furnace. The conduit can be made of
suitable size; and can be regulated by a valve or other means so as to carry such.a
supply of hot gases as shall sufficiently heat up the contents of the upper part of the
furnace and no more. According to these arrangements the furnace is divided into
two parts, an upper and a lower. In the upper part the gases descend and in the.
lower they ascend towards the outlet for the waste gases which is placed at the division
between the upper and the lower part of the furnace. The lower part of the furnace.
can be increased or diminished in height and the upper part can be diminished or
increased in height to suit the requirements of the material to be smelted.
'
The hot furnace gases to be drawn down to the tuyeres may, in some cases, be.
taken from any short distance above the tuyeres where they have a high temperature.
The adoption of this part of the invention may be of advantage by itself to any.
ordinary furnace. It is desirable to follow this course where it is desired. to allow all.
the gases descending in the upper part of the furnace to pass out of the furnace in,
order to carry off impurities which otherwise might enter the metal or regulus.
The arrangements described. will have advantages in enabling small concentrates.
and the dust of ores to be smelted without the loss which frequently takes place :by.
the dust of the ores and fuel being blown out at the top. Any dust of ores, escaping
from the blast furnace as above described, can be deposited in a catch-pool and made.
to flow into the hopper at the top of the furnace.
I. .
The arrangements described also afford facilities for eliminating impurities from.
ores &c. in the upper part of the blast furnace before the ores reach the zone of
fusion. In such cases the reductive gases, admitted near the top of the blast.
furnace, are allowed to descend and to leave the furnace along with the waste
gases arising from the zone of fusion, without any portion of them being drawn off
and burnt at the tuyeres, but a supply of the reductive inflammable gases may be
taken direct from the gas producing furnace to the tuyeres at the bottom of the blast.
furnace without passing through the upper part of the blast furnace, or otherwise;
a supply of inflammable furnace gases may be drawn down to the tuyeres from an
opening or openings a short distance above the tuyeres and below the outlet for the.
waste gases.
In furnaces for smelting such ores where it is desirable to prevent.
impurities therein from entering the regulus or metal, it may be desirable to have
the outlet-for the products of combustion at a short distance above the zone of fusion.
and to have the upper part of the furnace above such outlet made higher.
Where it is desired to carry off impurities both from the upper part of the furnace.
and also from the lower part, the upper part may be worked by means of reductive gases
from a gas producing furnace and the lower part by the air blast, through the tuyeres
with or without the addition of inflammable gases drawn either from the gas producing
furnace or from a short distance above the tuyeres:
:
By the arrangements described,, the heat in.the upper, as well as in the lower, part
of the blast furnace, is under the control of the furnaceman. He can increase it or

page_text: "
diminish it at pleasure, either in the lower or upper part of the furnace, and as the
reductive gases necessary in the upper part of the furnace can be supplied in sufficient.
quantity, either from the gas producing furnace, or by a conduit from the lower part
of the furnace, and gaseous fuel can also be obtained at the zone of fusion in sufficient
quantity to produce the heat necessary there, the fuel to be mixed with the ores and
charged into the blast furnace need not be more, or much more, than is required for
the chemical reactions in the two parts of the blast furnace. The fuel used both in.
the gas producing furnace, and also in the blast furnace, is consumed, especially
when the waste gases, issuing from the blast furnace, are burnt for heating air blast,
raising and superheating steam, or for heating a reverberatory furnace, so that the
entire heat, which the fuel is capable of producing is developed and utilised. In any
case the fuel can be so consumed that very little of its heating power is lost, and
there is also much additional reductive and fusing power got from the hydrogen
brought into the furnace. The use of hydrogen in the blast furnace, as being one of
the most effective reductive and heating agents known, will be of some value and
the arrangements described will enable it to be applied with great advantages.
In the Drawings Figure 1 shows a close topped iron smelting blast furnace A A¹,
with a close topped gas producing furnace B in an adjoining chamber C. The blast
furnace has an upper part A and a lower part A', and an outlet D for the waste gases
between them. This outlet D communicates with an opening or recess E made round
the inside of the brickwork of the furnace.
The waste gases, on passing out of the furnace, surround the gas producing
furnace B and then leave the chamber C by a down comer F to be used for heating
the air blast and for raising steam. The gas from the gas producing furnace B is
conducted by a pipe or passage G to near the top of the blast furnace, where it enters
and passes round in a channel H, made in the brickwork, whence it passes through
openings into the furnace, or it may pass direct from the pipe or passage G into
the recess H2. made round the inside of the brickwork of the furnace. It then passes
down through the ores and fuel in the upper part of the furnace, till the whole or
part of it is drawn off by a recess I made round the brickwork and communicating
with a passage J which leads it to a channel K whence it is drawn down through
passages K by and to the tuyeres L to be mixed with the air blast entering the
furnace and burnt therewith inside the furnace.
In the arrangement shown in Figure 2 the gas producing furnace is dispensed with
and a supply of hot gases is taken by a recess M round the inside of the brickwork
and an opening N in communication therewith a short distance above the tuyeres, and
conducted by a conduit G, built in firebrick, to near the top of the furnace where it
enters at H into a recess H* made round the inside of the brickwork of the furnace
and it then descends through the materials in the upper part of the furnace till the
whole or part of it is drawn off at I and conducted down by the conduit J to the
channel K whence it is led by passages K' to the tuyeres L to be mixed with the air
blast entering the furnace. The descending of the gases in the upper part of the
furnace is caused or promoted (1) by the pressure of the gases in the lower part of
the furnace, (2) the suction or exhaustion in the conduit J leading down to the tuyeres
caused by the force of the pressure air blast through the tuyeres, and (3) the draft of
the chimney acting through the outlet F for the waste gases. The opening N, in the.
lower part of the furnace for the gases going to the top of the furnace, may be much.
nearer to the tuyeres than is shewn in the Drawing. In this arrangement, hot air
blast and superheated steam may be introduced into the upper part of the furnace for
the purpose of forming hydrogen and carbon-oxide to aid the reductive action of the
furnace, and also to aid the fusing action at the tuyeres.
Figure 3 shews a furnace which may be a water-jacket furnace for smelting copper
ores, concentrates, &c. The gases descend in the upper and rise in the lower part of
the furnace. There is a passage N about two feet above the tuyeres communicating
with a conduit G which opens into the furnace at H' near, the top thereof. This
conduit G takes a regulated supply of hot furnace gases to the top of the furnace.
These gases and the volatile portions of the fuel descend through the upper portion.
~~.

page_text: of the furnace, and the whole or part thereof is then drawn off by a conduit J leading
to the tuyeres L in a manner similar to that described in reference to Figure 2. "The
waste gases pass off at F about half-way up the furnace to the chimney R. There is
a catch-pool S in the chimney for collecting flue dust and allowing it to run into the>
hopper T on the top of the furnace whence it enters the furnace with each successive
charge. Coal or coke or any kind of fuel may be used with this furnace.'
Similar letters of reference relate to like parts in all the figures of the Drawings.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
First In a blast furnace the use of a current of hot inflammable gases descending"
in the upper part thereof, substantially as herein before described.
Second In a blast furnace the use of a current of hot inflammable gases
descending in the upper part thereof, in combination with a current of furnace
gases ascending in the lower part thereof, the waste gases being caused to leave
the furnace at a point between the said upper and lower parts, substantially as
hereinbefore described, and illustrated in the Drawings hereto annexed.
Third In a blast furnace supplying hot inflammable gas intended to descend in the .
upper part of the furnace either from a gas producing furnace or from the lower part
of the blast furnace itself, substantially as hereinbefore described, and illustrated in
the Drawings hereto annexed.
Fourth In a blast furnace, forcing hot inflammable gases thereinto along with the
pressure air blast by means of the tuyeres, substantially as hereinbefore described, and
illustrated in the Drawings hereto annexed.
Fifth In a blast furnace drawing off hot furnace gases above the the tnyeres and
mixing such gases with the air blast at the tuyeres, substantially as herein before
described, and illustrated in the Drawings hereto annexed.
Sixth The use of a gas producing furnace in connection with a blast furnace,
substantially as hereinbefore described, and illustrated in Figure 1 of the Drawings
hereto annexed.
DL: of March 1800