Improvements in the Manufacture or Production of Metals from their Ores, and in Plant or Apparatus therefor.
Year: 1893

page_text: Date of Application, 14th Oct., 1893
Complete Specification Left, 24th Oct., 1893-Accepted, 4th Aug., 1894
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture or Production of Metals from
their Ores, and in Plant or Apparatus therefor.
I, WLADIMIR FEDOROVITSCH BERNER, of Angle Newsky Prospect and
Snamenskaja, St. Petersburg, Russia, Engineer of Mines and Member of the
Russian Imperial Council of State and Knight, do hereby declare the nature of
this invention to be as follows:-
This invention relates to improvements in the method of obtaining metals direct
from the ores with the simultaneous and continuous production of various kinds of
smelting products of good quality and with great economy of fuel (solid and
gaseous); and to improvements in plant or apparatus for putting this process into
execution, said plant or apparatus comprising a regenerative blast furnace, worked
in a special manner with solid fuel and injected gases, refining chambers adapted
to be placed in direct connection with the hearths of the blast furnace, a gas
generator for the production of the gaseous mixture necessary for carrying out
the said process and a special arrangement of apparatus for the production of
the air blast.
For the purpose of smelting down the ores, the furnace, which comprises two
precisely similar halves forming separate furnaces, is either worked one half
with blast, air being blown into it at various heights in order to effect continuous
reduction, whilst the other half of the furnace takes in by suction the gas circu-
lating in the first half of the furnace, together with heated air from a regenerator
and gaseous mixture produced in a gas generator in order to create a high
temperature suitable for decarbonizing; or both halves of the furnace are worked
with blast for the purpose of simultaneously smelting; or one half alone is put
into operation, in which case the annexed refining-chambers may be worked either
in connection with the furnace or independently thereof.
The gas and air conduits are so arranged that the furnace can be adapted to the
kind of smelting product to be obtained, so that the most thorough decomposition
and consumption of the products of combustion, as well as the removal of the
carbonic acid (which is injurious to the process), the increase of the strength of the
reaction by the heating of the blast from the exterior, and the drawing of the air
into the furnace and the generator in an already heated condition is effected; and,
moreover, the running of the smelted metal out of the smelting-chamber direct into
the refining-chamber in a distinct and independent manner from the tap-hole of the
smelting-chamber is possible.
The reduction and oxidation process can consequently be performed in the two
halves of the furnace, either alternately or simultaneously, and it may be
accelerated by external heating with a diminution of the consumption of fuel in
the furnaces, and an increased production obtained, even with plant of small
dimensions.
In the accompanying drawings an arrangement of plant or apparatus is repre-
sented, which is particularly suitable for obtaining iron direct from its ores in the
form of pig-iron, steel, or wrought iron.
Fig. 1 represents the regenerative blast-furnace with the annexed refining-
chambers, half in elevation and half in vertical section.
Fig. 2 is a vertical cross section on the line I-I of Fig. 1.
Fig. 3 shows a plan of the whole plant, in which one of the blast-furnaces
together with the refining-chamber appertaining thereto is represented in

page_text: horizontal section on the line II-II of Fig. 1 and the other in section on the
line III-III.
Fig. 4 is a horizontal section through one of the blast-furnaces on the line IV-IV
of Fig. 2.
Fig. 5 is a horizontal section through one blast-furnace on the line V-V of
Fig. 2 and through the other on the line VI-VI.
Fig. 6 is a separate view of the shutting off apparatus between blast-furnace
and refining-chamber.
Fig. 7 is a vertical section through the gas generator.
Fig. 8 is a vertical cross section, half on the line I-I¹ and half on the
line II-II, of Fig. 7.
Figs. 9 to 12 are horizontal sections through the gas generator on the
lines III III¹, IV'—IV¹, V¹-V₁, and VI-VI³, respectively, of Fig. 7.
Figs. 13 and 14 show to a larger scale in sectional elevation and sectional plan,
a reversing-valve used in this gas generator.
As is seen in Fig. 1, the regenerative blast-furnace consists of two exactly
similar halves, each of which contains two shafts A, B or A', B' which are separated
by a partition f, but unite below in a common hearth C or C' that is adapted to be
placed in connection with the respective refining-chambers D, D¹, each pair of
shafts being provided at the top with a charging-arrangement E or E¹.
The partitions, which for the purpose of greater firmness are strengthened by
several arches, serve to diminish the breadth of the charge so that the latter can
be better permeated on the one hand by gases generated by the combustion of
solid fuel in the furnace and on the other hand by injected gases and also by the
air-blast.
The construction of the furnace in two equal balves renders it possible to
reduce the height of the same relatively to existing blast-furnaces and thereby to.
obviate the disadvantages of high furnaces.
The charging-arrangement consists of an iron box resting partly on the partition
and partly on the walls of the furnace, and closed at the bottom by lids a and at
the top by a hinged cover b. In order to prevent the hinges of the lids and their
bearings from becoming dirty during charging, they are covered with a roof-like
cover c. The lids rest on bolts or catches e and are free to turn down or open upon
the said bolts or catches being drawn out, whilst they are closed by means of a
lever or crank 1. A winch d serves for opening and closing the cover b.
During charging, the cover b is open and the lids shut, so that the circulation of
the gases in the furnace is not interfered with and their escape is prevented. After
the cover b has been closed the bolts or catches are drawn out so that the charge
lying on the lids falls into the furnace in consequence of the dropping of the
latter.
Each of the shafts A and A¹ situate on the outer sides of the furnace is provided
with a gas outlet F or F'; and each of the inner shafts B and B is provided with
two small gas outlets G or G'.
The gases escaping from the two shafts of each half of the furnace (hereinafter
termed gaseous products) pass through distributing apparatus K, K' and pipes H H¹
which discharge into two gas purifiers I, 1', through the inner tubes thereol whence
they can be led off as required by pipes 24 into steam boilers, gas generators,
regenerators, roasting-furnaces, and other auxiliary apparatus, or by pipes 25 into
burners Q.
For the purpose of regulating the flow, each half of the furnace is provided with
a distributing apparatus J or J, which consists of a cylindrical box in which a
cover or valve n can be raised or lowered by a suitable lifting apparatus and thereby
the communication between the purifiers I, l' and the gas outlet F, F¹ can be
established or interrupted.
The two halves of the furnace are connected together by a regulator P, and by
the conduit pipes 3. The regulator which serves as a holder for gas coming from
the generator (hereinafter termed generator gas) through the pipe 1, is connected

page_text: with the inner shafts B and B' by tubes 2 that are provided with shut-off
dampers w, by which the flow of gas from one of the halves of the furnace to the
other is regulated.
This regulator, the pipes 2 and the furnace shafts are constructed of refractory
material and enclosed in an iron casing; the regulator is provided at the top with
a pipe o furnished with a safety valve and at the bottom with a water pipe p for the
purpose of cooling and retaining coal and ore dust.
The entire furnace rests on hollow pillars M and N, which serve as gas conduits
and air conduits respectively. Each pillar consists of four cast iron columns 9, which
are united by bolts and nuts, and of a tube 15 or 16 of refractory material, the
corners of which are embedded in the columns. The tubes are covered externally
with brick work t from top to bottom and the spaces between the latter and
the tubes are filled up with sand in order to prevent the gases passing through
the joints of the tubes and the consequent loss of heat. The columns of each
pillar have a common support i and top piece j; on the latter rest the beanis or
girders R, which are covered with cast iron plates which carry the shafts.
The pillars M and N may if preferred be cast hollow, in which case the aforesaid
tubes 15 and 16 pass through them and through corresponding holes in the top
pieces and supports. At the bottom, the pillars M communicate with gas
regenerators by means of conduits 4 and 5, and the pillars N with air regenerators
by means of conduits 6 and 7; at the top, the former are connected with gas
jackets O, O' which are arranged around the shafts, and the latter with air conduits 8
which are arranged beneath the corresponding gas jackets. For the purpose of
enabling the gases to enter and leave, conduits 9 and. 10 lead upwards from the gas
jackets and are capable of being shut off by dampers Z of refractory material;
these conduits and the gas jackets, communicate with the furnace shafts through
passages 11 or 12 respectively. Into the hearth also gas and air supply conduits 13
and 14 open so that the gases from the conduits 4 and 5 and the air from the conduits 6
and 7 can also be introduced at the upper part of the smelting-zone.
The conduits 4 and 6 serve moreover for connecting together the gas conduit
pillars M and the air conduit pillars N respectively of each half of the furnace.
The heating of the regenerators is effected by means of the gaseous products
which are ignited by a burner Q situate between each pair of regenerators.
Each burner, which is connected with the regenerators by conduits 17, consists
preferably of a wide vertical tube open towards the fire space or of a shallow gas
chamber into which the gaseous products flow laterally, and in the outer bottom
plate of the chamber are inserted air supply pipes which pass through this chamber
longitudinally the inlet openings of which can be regulated by means of a perforated
slide.
The upper part of each of the hearths C and C is situated within a cast iron
envelope or casing which is strengthened inside by ribs and the upper rim or flange
of which ties on the beams R that support the shaft.
Each hearth is connected with one of the refining-chambers D, D' by means
These
of a slightly inclined conduit 18 which can be closed by a slide m.
refining-chambers are constructed in the manner of Siemens-Martin furnaces, the
charging of them being directly effected by the discharge of the fluid metal from
the hearth, and the running off of the finished cast taking place at the narrow
side or end of the refining-chamber.
Each hearth is, moreover, provided with a tap-hole y for running off the cast
iron, and above the latter with a slag hole x.
Each slide m (Fig. 6) is made of refractory material a' in which is inserted a
square iron rod 61 which is provided with projecting step-like shoulders b', and is
held in place by a wedge c¹ of fire clay. This slide is at the top enclosed in an iron
frame d which is attached to the refractory material a' by bolts e¹ and to the rod b¹
by bolts f. The upper end of the rod b' is screw-threaded and ou it is arranged a
bevel wheel, correspondingly screw-threaded, which is prevented from moving
longitudinally and which engages with a bevel wheel ¹ located on the shaft ¹ that

page_text: is capable of rotation by means of the hand-wheel g', for the purpose of raising and
lowering the slide m; by means of this arrangement the communication between the
hearth and the refining-chamber is opened or closed.
To each of the gas and air regenerators Y and Z the flame from a burner Qis
conducted by the hereinbefore mentioned conduits 17; the flame is caused to enter
each of the two regenerators alternately by means of a slide made of refractory
material. The regenerators Y and Z instead of being furnished with ordinary
reversing valves, are provided with cocks S (Fig. 3) made of refractory material,
which are better able to withstand the action of the heat.
The regenerators for the hearths C and C¹ are heated by the gaseous products,
and those of the refining-chambers D D' by means of the flame and hot gases
escaping therefrom. They are in communication with injectors or fans by
conduits 19 (Fig. 3) and with flues 21 and with the main outlet conduit 22 by
conduits 20; the conduits 21 serve for heating the bottom of the hearth by the
used up gases of combustion, whereas. in the outlet conduit are inserted pipes s
which serve for heating the compressed air. The air is conducted to the
regenerators through slag-pits 23 and is thereby preparatorily heated.
The refining-chambers D, D' may also be heated directly by the regenerators
belonging to the shafts of the furnace, if the gases and the air from the pillars M
and N be led into the refining-chambers whilst the flame from the opposite side
thereof be led into the flue 21, which is not, however, recommended because then
the gases are directed to one side only.
Each hearth C, C is furnished with five holes and tuyeres 9 through which air
can be blown in from the air conduit pipes L, L'. These air conduit pipes are also
in communication with pipes T, T¹ (Fig. 2) to enable air to be blown into the
passages 11 and 12, which is effected by means of special tuyere-pipes made of
graphite.
It is of the greatest importance for producing the best results and at the same
ime to enable the operation of the regenerative blast-furnace herein before described
Lo De most economically effected, that the quality of the generator-gas be such as
to produce the high temperature necessary. For this purpose generator-gas is
employed which consists of a mixture of ordinary generator-gas and water-gas,
(hereinafter designated mixture gas); it is prepared in a generator of special
construction.
This gas-generator, which is represented in Figs. 7-12, consists of two
shafts AA2 which are divided by a partition wall. Each shaft is provided with
an arrangement for charging with fuel similar to that described with reference to
the furnace. The gas outlets a², a² are alternately connected with the gas-
conduit C² by means of conduits 62, which are capable of being closed by
slides. Underneath the partition wall, where the two shafts unite, a steam
conduit passage discharges. Sight-holes d2 and openings e² for cleaning out
the cinders and ashes and capable of being closed are provided at suitable places.
Above the gas outlets are situated small tuyeres f, and at the broadest part
of the shaft large tuyeres 92 into which enters air from the air conduit 2 and
into which discharge the pipes 2 which lead from the steam passage ².
Both of the shafts A2 are heated externally by the gaseous products from the
generator; for this purpose vertical channels k² are provided which are connected
at the bottom with the conduit 12, which surrounds the generator on two or three
sides and heats it underneath, where it is also thoroughly heated by a burner Q,
arranged in the same way as in the furnace, and by means of the passage m².
The heating-channels k² are connected at the upper part with a passage n² for
heating the coal-holders o²; this passage has inserted for this purpose at several
places, grates p2, and communicates with the flue y² through the passage q². From
the burner Q, passages 2, which are capable of being closed by fire-proof slides s²,
lead to the regenerator-chambers B2 which serve to heat the steam entering the
same through tubes 2, and can be placed in communication either with the flue y
or with the steam passage j² by means of the passages u³ and v², through which

page_text: passage the steam that has been superheated in the regenerator-chambers is blown
into the generator from the pipes 2 by means of a weak jet of air. The alternate
connection of the regenerator-chamber with the flue, or the steam passage, takes
place with the help of an elliptical valve c² (Figs. 9, 13 and 14). This valve, which
is arranged in the cylindrical passage at a suitable angle to the axis of the latter,
is fixed on a rod w², which serves for turning it; the rod w² is provided with a hand
crank a², and is mounted in an annular bearing in the cover in such a manner
that when pressure perpendicular to the rod w² is exerted on the hand-crank, this
rod makes a certain angle with the axis of the passage 2, whereby the partial
rotation of the valve c by the rod is facilitated, since the valve then touches the
passage walls only with those portions of its edge situated near the ends of its short
axis. After the rod of the valve has been rotated through 180° it is moved back
within its annular bearing until it again coincides with the axis of the passage v², so
that the valve then lies with the whole of its periphery in contact with the walls
of the passage.
In this manner, in one position of the valve the communication between one of
the regenerator-chambers and the steam-passage and between the other chamber
and the flue is established, and by shifting the valve this communication is
reversed.
The passage 2 is preferably made in a single piece of fire-clay and is placed in a
corresponding cavity in the gas generator, which is preferably surrounded by an
iron casing.
Each air regenerator, which is employed for the purpose of obviating the use of
the costly blast-heating stoves, is similar to an ordinary Siemens regenerator, but
is provided with special air-inlets in order to prevent destruction or injury produced
through the blowing in of air by means of ordinary blast-engines.
The suction of the air in this case takes place out of special regenerators by
means of injectors V (Fig. 3) made of aluminium bronze.
The injectors are worked by means of compressed air; the air, compressed by a
compresser U (Fig. 3) passes into a regulator X and thence through the tubes s to
the injectors. The atmospheric air heated in the regenerators is in consequence of
this sucked in and ascends through the conduit 19 (Fig. 3), is thus freed from dust
and brought to grates or grids of aluminium brouze which retain any solid con-
stituents travelling along with it. The purified air passes through openings in the
injectors, mixes there with the compressed air and is, in consequence of the
expansion of the latter on passing through the nozzles of the injectors, compressed
in such a manner that it enters the blast-conduit with sufficient pressure, and at a
temperature of 500-600° C., to which the air must be brought for the purpose of
smelting. The force necessary for transferring the air from the regenerators into
the furnace and for overcoming the resistance in the latter is quite as great as in
the case of the application of blast-engines and blast-heating apparatus. The
cooling of the compressed air in the injectors is completely compensated for by
the heating of the same in the tubess which are placed for this purpose in
the flue.
The suction and blowing-in of the air heated in the regenerators can be also
produced by means of fans, which according to the temperature to be produced, are
constructed of cast iron for temperatures below 400° C. or of aluminium bronze for
temperatures below 700° C. Through the same force out of the blast-conduit
follows quite independently of the operation just described the blowing-in of the
air out of the air-chambers of the regenerators of each half of the furnace; the
regulation of the drawn-in quantity of air is effected in this case by means of
the slides w and w¹ (Fig. 2). The atmospheric air preparatorily to entering the
regenerators is heated by the heat of the hot slag and pieces of cast-iron which are
put for this purpose into the slag-pits 23, which are situate before each of the
cocks S.
In this manner the introduction of air sufficiently heated is rendered possible
without the use of blast-heaters and blast-engines which however may remain in

page_text: employment if they are already provided in a phant, in which case a pair of
regenerators is unnecessary.
The process of working the furnace is as follows:-
The furnace is first fed with coal and heated both internally and externally
with hermetically closed tuyeres and blast-conduits, in order to dry the furnace.
During this time the covers or valves n of the gas-distributers J, J and the valves
of the gas-conduit pipes 3, and of the regulator P through which the two halves of
the furnace are in communication with each other, are opened and the gaseous
products are free to pass through the burner Q to the regenerators.
The flame passes through the conduits 21 situate under the bottom of the furnace,
dries the furnace, and issues ultimately by the flues 22. In this manner a uniform
and quick drying is possible, the progress of which can be observed through sight-
holes in the shafts and the refining-chambers and the completion of which can be
ascertained from the humidity of the products of combustion.
After the drying follows the heating-up of the furnace. At the time of the
delivery of the charge (ores mixed with fluxes) it is next to be observed, according
to the size of the furnace and the number of layers, if the charge approaches the
tuyeres; if there remains below the tuyeres still room for about twenty more
charges, then a weak blast is blown into both halves of the furnace. If the descent
of the charges is uniform in the two halves of the furnace, then this shows that the
same conditions exist in the two halves of the furnace; if, on the contrary, there is
an un-uniform descent, then the operation is regulated by blowing more blast into
the corresponding half of the furnace.
As soon as the smelting-process has commenced, i.e. as soon
as cast-iron
appears in the hearth, the connection between the hearths C, C¹ and the refining-
chambers D, D¹ is broken by lowering the slides m without, however, interrupting
the heating of the refining-chambers. When a sufficient quantity of liquid pig-iron
has collected, it is allowed to flow out through the opening y beneath the slag-hole a
for the first test, by which it is ascertained whether the smelting of the cast-iron is
being conducted in the two halves of the furnace in the same and in a correct
manner. If this is the case, the cast-iron is now, by raising the slides m, allowed to
flow from the hearths into the refining-chambers, in order to be therein fined or
refined. For this purpose the covers or valves n of the two gas-distributers J, J¹
are then alternately closed for equal periods, i.e. the one remains open and
consequently the corresponding gas-distributer is in communication with the
chimney, whilst the other is closed.
On this periodical changing of the covers or valves n is principally dependent
the further operation of the furnace, the motion of the gases and the quality of the
smelted product. To particularize, air is blown through the tuyeres q and also
through all the injector passages 13, 14 into the half of the furnace in which the
cover or valve n is closed after the cast-iron bas been allowed to run into the
refining-chamber; whereas, during this time, in the other half of the furnace
the blast is stopped and the cast-iron is retained in the hearth of this half of the
furnace by the lowering of the slide m. Instead of the blast, air and mixture gas
now pass into the latter half of the furnace in order to increase the temperature
therein as much as possible and to produce a vigorous action of them on the cast-
iron and the reduction of the ore. This is effected by the help of the gases
flowing in from the first half of the furnace, which have access at three different
levels by means of the open valves w of the regulator P and of the gas-conduit 3
between the two halves of the furnace.
At this time the fire-proof valves z of the conduits 9 and 10 must remain closed,
as otherwise the gases would flow from the gas-jacket O through these conduits
into the upper part of the shaft and thence direct to the outlet F or F' without
having been used up for the smelting column, whereas when the valves are closed
the gases spread through the entire smelting-column, and effect the reduction of the
_layers of ore.
The mode of operation of the furnace characterized by this different motion of

page_text: the gases in the two halves of the furnace, one of these being worked wi
operates further as follows:-
I. In the refining-chamber D of the first half of the furnace which is shut off
by the closed slide m, the refining of the molten pig-iron previously run into it is
proceeded with in the usual manner by the introduction of gas and air, whilst into
the hearth C of the same half of the furnace, blast is blown by the tuyeres q and the
injection-conduits 13 and 14. Out of the latter the heated gases and air from the
regenerators are forced by the blast into the upper part of the hearth; whilst
the gaseous products which issue from the shaft through the outlet passages 12,
mix in the gas-jacket O with the generator-gas, which reaches the gas-jacket by
the pillars M, and are blown at the top on one side into the furnace, whilst on
the opposite side the gaseous-products issue through the outlet-passages 12:
downwards and are blown into the shaft mixed with the regenerator gas.
The preparatorily heated air led into the air-conduit 8 is blown in under the
partition-wall of this shaft by the same blast. The blowing-in of gas and air is
not allowed to take place in the shaft at the same level, in order to prevent a
premature smelting of the ore and to produce a reduction-zone of greater height.
In this manner there are created, so, to speak, two burning-points in the shaft
(one in the upper part and one in the lower part) which are situate opposite the
injection-passages 11 & 14 and produce a high temperature. Between these two
points the following takes place:
(1.) The reduction of the ores. This is produced by the heating of the shaft
from inside at the expense of the heat of the gases that pass through the gas-
jacket O and of the heat of the air heated in the regenerator, which is conveyed
by the pillars N iuto the air-passage 8. In order to heat the shaft from the inside
yet more powerfully, burners for burning fuel of inferior quality may be inserted
in the man-holes shown in the drawing (Fig. 1) so that, if air of a certain
pressure is uninterruptedly blown in through the air-conduit, a constant flame is
produced by the burners.
(2.) The enrichment of the products of combustion through the presence of
glowing coal and in-blown blast, the same being decomposed and fresh heat-
producing gases thus formed.
(3.) The re-combination of the gases and the using-up of their heat in con-
sequence of the constant circulation of the gases from the upper to the lower part
and vice versa, until they are expelled by the gases formed in the shaft and those
coming from the regenerators.
(4.) A novel motion of the gases, since when the cover or valve of the gas-
distributer of one of the halves of the furnace is closed the gases formed by the
in-blown blast in the first shaft descend under the partition-wall, travel upwards in
the other shaft, and so participate in the reactions named under (1), (2), and (3),
whereby they pass through the entire smelting layers in different directions and
effect the complete reduction of the ores; the consequence of this is that charges
can be more frequently introduced and therefore the rate of production of the
furnace is increased although the furnace is of comparatively small dimensions
and a small quantity of fuel is employed.
In ordinary furnaces the conversion of the carbonic acid formed above the
tuyeres q into the carbonic oxide, necessary for the reduction, in the presence of
coal made incandescent by the blast, takes place only once, because on the further
quick upward motion of the gases through the charge the carbonic oxide is mixed
with carbonic acid and neutralized, i.e. is without effect on the reduction, which is
proved by the presence of carbonic oxide in the gaseous products, whereas in this
furnace arrangement the gases are retained a longer time in the furnace and are in
constant motion therein. In consequence of this there are constantly formed by
the action of the in-blown blast on the glowing coal, carbonic oxide from the
carbonic acid, and carbonic oxide and hydrogen from the steam. The decomposition
of the products of combustion takes place several times and in different layers,.

page_text: whilst the coal is simultaneously changed into carbonic oxide, which change is
advantageous for the reduction of the ores.
Consequently the reduction-zone is situated in that part of the furnace which is
located between the two aforesaid burning-points. The heat-producing gases,
which are formed by the repeated decomposition of the products of combustion in
the presence of the coal rendered incandescent by the blast, are constantly
produced with a small consumption of introduced air, and contain consequently
very little nitrogen. As the oxygen taken from these products of combustion is
not mixed with any nitrogen much fuel is saved; whereas in the ordinary blast-
furnace process much heat is taken up by nitrogen and other inert gases.
As the carbonic oxide serves principally for raising the temperature of the
reduced cast-iron to the white-heat (1300° (.) necessary for the production of
wrought-iron, for each volume of the burnt carbonic oxide, 10 volumes of the gas
must remain unburnt. This is made possible by the furnace arrangement herein-
before described, in which the following operations take place
(1.) The products of combustion are uninterruptedly regenerated at the expense
of the carbon of the fuel rendered glowing by blast; (2.) a fresh quantity of
heat-producing gas is introduced from the exterior, which gas is formed in the
generator and contains hydrogen which serves for the reduction of the ores and
for freeing the ores from sulphur; (3.) the temperature of the furnace is raised by
the external heating of the shaft, so that the chemical reactions can take place
more easily.
The gases, which increase the heating-power of the combustible matter in the
shaft, pass into the furnace (a) through the regulator that connects the two halves
of the furnace (b) through the regenerators into the smelting-space, and (c) through
the conduits of the pillars out of the same regenerators into the shaft.
The gases may be blown in by a blast or set in motion by the draught of a
chimney.
In this manner in the half of the furnace that is worked by means of blast
there is effected (1) the preparation of the ores and of the fuel by driving out the
hygroscopic water and the products of distillation; (2) the mixture of the furnace-
gases with the generator gases, which latter consist of a mixture of ordinary
generator-gas with water-gas; (3) the reduction of the ores; (4) the regeneration
of the products of combustion; (5) the carbonization of the reduced iron; (6) the
formation of the gases out of the solid coal; and (7) the smelting of the cast-iron.
11. In the second half of the furnace, which is exposed to the suction of the
chimney through its connection therewith, the more or less heated gases that pass
over from the first half of the furnace through the regulator P, give up their heat,
flow, in consequence of the draught, out of the first shaft B' under the partition-
wall into the second shaft A', reduce thereby the ores, and escape into the gas-
outlets F, G. At the same time very highly heated gases and air are drawn into
the hearth C¹ from the regenerators, which gases and air produce on burning a
temperature of about 2200° C., which is rendered possible by the peculiar nature
of the gas produced in the generators and by all the other reactions that are
proceeding in the first half of the furnace.
In consequence of this high temperature no carbonization of the iron takes place as
in the first half of the furnace, in which a considerable cooling occurs in consequence
of the decomposition of the products of combustion, but the reduced iron sponge
passes into the hearth and is dissolved there in the previously smelted cast-iron,
whereby a partial decarbonization of the cast-iron is produced and the mass is
converted into a thick fluid.
As soon as this occurs the reversal of the working action of the furnace must be
effected by reversing the covers or valves n in the gas-distributers J, J and the
smelting of the cast-iron and of the ores is then proceeded with in the second half
of the furnace in the manner hereinbefore described with reference to the other
half. By this means the metal becomes carbonized and consequently fluid; and a

page_text: steel-like mass is obtained which is allowed to flow into the refining-chamber D³
(together with the slag) for the purpose of being refined. During this time in
certain cases scrap-iron of different kinds can be added to the refining chamber D¹,
after being preparatorily heated. The refining-chamber is then shut off from the
hearth by again lowering the slide m and the entire contents of the refining-
chamber refined at a high temperature produced by the burning of the mixture gas.
By the introduction of suitable flues the desired nature is given to the metal.
In the hearth of the same half of the furnace, after the reversal of the covers or
valves, the smelting of the cast-iron proceeded with in the same manner until the
reversed operation is caused to commence in the other half of the furnace by
reversal, and so on.
In case the cast-iron is to be smelted in both halves of the furnace simultaneously,
the connection between the hearths and the refining-chambers is broken and heated
blast is blown into the tuyeres of both halves of the furnace. At the same time
the refining of the products obtained can be proceeded with in the refining-chambers
and the heat therein generated be used for heating the furnace-hearths at the
bottom and at the slides m.
Such a working of the furnace is useful if, notwithstanding the careful execution
of the operation, the fluid metal should become viscous in consequence of the
formation of bears and crusts, which may be caused for example, by the cooling of
the regenerators and the consequent cooling of the hearths. In this case, blast is
blown-in through all the tuyeres and the covers or valves of the gas-distributers J, J¹
and K, K' are opened whereby the metal is again made liquid.
The gases and air thus blown-in are not lost but still further promote the
smelting.
The gaseous products in excess are employed for the heating of all the auxiliary
apparatus, whilst the bears and crusts are dissolved by the ample production of
slag and cast-iron; also the freezing of the furnace need not be feared.
The mode of operation of the gas generator employed in the hereinbefore
described method of furnace-working, for the production of the semi-water-gas or
mixture gas is as follows:-
In the
In the divided shaft of the same, the blast is alternately introduced at certain
intervals into the one or the other half A2 from the top and from the bottom.
During this time the slide of one of the gas-outlet conduits a² is closed and the
other open, so that the latter is in communication with the gas-conduit C².
air-conduit situate above the gas-outlet conduit, the slides are arranged in
the reverse manner. In consequence of this the one half of the shaft is heated,
the volatile constituents and the moisture of the coal are driven out by means of the
blast through the top tuyeres 2, whilst the resulting distillation-products are
consumed at the lower tuyeres g. Simultaneously in the other preparatorily heated
half A2 of the shaft there is proceeding in the presence of glowing coal, the
decomposition of the carbonic acid and of the superheated steam, which is introduced
by means of the blast through the conduit j². The gas from this half of the shaft
is ready for use. The superheating of the steam takes place in the regenerator-
chambers B which are situated under the shaft and are heated by the gaseous
products from the furnace.
In order to facilitate the re-actions proceeding in the gas generator, the latter si
as hereinbefore stated, heated externally by the escaping gases which pass through
the passages 12, k², n², m² and heat the walls of the generator, the heat from these
passages together with that from the regenerators B3 serving to heat the bottom of
the gas generator, and also to dry the coal contained in the coal-holders o².
When in consequence of the formation of the semi-water-gas or mixture gas, the
cooling of the corresponding half of the generator commences, the slides are reversed
and the same process is commenced in this half as formerly took place in the other
half; viz. dry distillation, the heating of the coal, the burning of the distillation-
products at the lower tuyeres, and the formation of the gases, whilst in the other
B

page_text: half of the shaft the decomposition of the products of combustion and of the steam
is proceeding. The mixture gas produced is led away in the furnace and effects
by the production of a high temperature the herein before mentioned re-action.
The hereinbefore described regenerative blast-furnace may be constructed of
such a size as to be suitable for smelting other ores the layers of ore and fluxes
being then selected so that any iron contained in the ore goes into the slag. In
one half of the furnace the raw ore is smelted, whilst in the other half of the
furnace the pure metal is obtained from the products of the smelting in the first
half.
By the alternately or simultaneously conducted reduction and oxidation of the
products of smelting, the sulphur and the iron are removed from the same; where-
upon the metal is freed from oxides by stirring in the refining-chambers, which are
shut off from the hearth.
This furnace offers therefore the following advantages:
:-
(1.) The working can be carried on in the two halves of the furnace as desired,
by means of the gas-distributing apparatus by reversing the flow of the gas, and
thus the reduction and oxidation processes can proceed in the two halves of the
furnace according to requirement either simultaneously or alternately.
(2.) The gases enriched in the shafts can be mixed with the semi-water-gas or
mixture gas heated in the regenerators, and be uninterruptedly employed for the
metallurgical processes.
(3.) The quantity of fuel used in the interior of the furnace is reduced by the
uninterrupted external heating of the furnace-shafts and at the same time the
re-actions are accelerated.
(4.) The furnace can be more frequently charged, i.e. a large production can be
obtained with apparatus of comparatively small dimensions.
(5.) The heat of the hot slag and of the cast metal is supplied to the cooling
furnace.
(6.) By the motion of the gases in the furnace in different directions their heat
is completely utilized; and as they are blown in by means of the blast and the
oxygen of the products of combustion is used up, smaller quantities of blast and
fuel are necessary, and by the formation of the necessary quantity of carbonic oxide
the iron is protected from the action of the carbonic acid.
(7.) By the drawing-in of the gases and air, a high temperature, which prevents
carbonizing, is produced in the half of the furnace which is connected with the
chimney and in which the refining is taking place.
(8.) The blowing of hot blast of adequate pressure into the furnace can be
effected in a simple and economical manner.
(9.) The production of wrought-iron is possible without any loss of heat, since
the smelted pig-iron is run direct from the furnace-hearths into the refining-
chambers.
(10.) The two halves of the furnace can be worked independently of each other,
and one half can, when required, be put entirely out of action.
(11.) Smelting-products of various kinds can be produced; e.g. by working
iron-ores, cast-iron, wrought-iron, or steel can be produced.
Metal of good quality is produced by means of this furnace, an economy of
gaseous and solid fuel being obtained, which may be further increased if the heat
which is lost by the cooling of the hearth is made useful, which may be effected by
lining the walls and bottom of the hearth with carbonaceous bricks, or with
magnesite. This living with magnesite may also be provided in the refining-
chamber, in which case the same is inlaid with a basic addition for the purpose of
de-phosphorizing the ores, as isolated layers between Dinas-bricks and dolomite.
Dated this 14th day of October 1893.

page_text: UUMI LEIE O
Improvements in the Manufacture or Production of Metals from
their Ores, and in Plant or Apparatus therefor.
I, WLADIMIR FEDOROVITSCH BERNER, of 120, Corner Nevsky and Snamenskaja
St. Petersburg, Russia, State Councillor and Mining Engineer, 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 :-
This invention relates to improvements in the method of obtaining metals direct
from their ores with the simultaneous and continuous production of various products
of the smelting operations, all of good quality and with great economy of fuel (solid
and gaseous); and to improvements in plant or apparatus for putting this process
into execution, said plant or apparatus comprising a regenerative blast furnace
worked with solid fuel and with injected gases of a particular nature, refining
chambers adapted to be placed in direct connection with the hearths of the blast
furnace, a gas generator for the production of the gaseous mixture necessary for
carrying out the said process, and a special arrangement of apparatus for the
production of the air blast.
For the purpose of smelting down the ores, the furnace, which comprises two
precisely similar halves forming separate furnaces, is either worked one half with
blast, air being blown into it at various heights in order to effect continuous
reduction, whilst the other half of the furnace takes in by suction the gas circulating
in the first half of the furnace together with heated air from regenerators and
gaseous mixture produced in a gas generator in order to create a high temperature
suitable for decarburising; or both halves of the furnace are worked with blast for
the purpose of simultaneously smelting; or one half alone may be put into operation;
in either case the annexed refining chambers may be worked either in connection
with the furnace or independently thereof.
The gas and air conduits are so arranged that the furnace can be adapted to the
kind of smelting product to be obtained, so that the most thorough decomposition
and consumption of the products of combustion are effected, as well as the removal
of the carbonic acid (which is injurious to the process), the increase of the strength
of the reaction by the heating of the shaft from the exterior, and the drawing of
the air into the furnace and the generator in an already heated condition; and,
moreover, the running of the smelted metal out of the smelting-chamber direct into
the refining-chamber in a distinct and independent manner from the the tap-hole of
the smelting-chamber is possible.
The reduction and oxidation processes can consequently be performed in the two
halves of the furnace, either alternately or simultaneously, and they may be
accelerated by external heating with a diminution of the consumption of fuel in
the furnaces, and an increased production obtained, even with plant of small
dimensions.
In the drawings filed with my Provisional Specification an arrangement of plant
or apparatus is represented, which is particularly suitable for obtaining iron direct
from its ores in the form of pig-iron, steel, or wrought iron.
Fig. 1 represents the regenerative blast-furnace with the annexed refining-
chambers, half in elevation and half in vertical section.
Fig. 2 is a vertical cross section on the line I-I of Fig. 1.
Fig. 3 shows a plan of the whole plant, in which one of the blast-furnaces
together with the refining-chamber appertaining thereto is represented in horizontal
section on the line II-II of Fig. 1 and the other in section on the line III-III
of Fig. 1.
Fig. 4 is a horizontal section through one of the blast-furnaces on the line IV-IV
of Fio 2

page_text: is a norizontal section through one blast-furnace on the line V-V and
through the other on the line VI-VI of Fig. 2.
Fig. 6 is a separate view of the shutting off apparatus between blast-furnace and
refining-chamber.
Fig. 7 is a vertical section through the gas generator.
Fig. 8 is a vertical cross section, half on the line I-I' and half on the
line II-II, of Fig. 7.
Figs. 9 to 12 are horizontal sections through the gas generator on the
lines III-III', 1V-IV, V-V, and VI-VI, respectively of Fig. 7.
Figs. 13 and 14 show to a larger scale in sectional elevation and sectional plan, a
reversing-valve used in this gas generator.
As is seen in Fig. 1, the regenerative blast-furnace consists of two exactly
similar halves, each of which contains two shafts A, B or A¹, B' which are
separated by a partition f, but unite below in a common hearth C or C' that
is adapted to be placed in connection with the respective refining-chambers D, D',
each pair of shafts being provided at the top with a charging arrangement E or E'.
The partitions, which for the purpose of greater firmness are strengthened by
several arches, serve to diminish the breadth of the charge so that the latter can
be better permeated on the one hand by gases generated by the combustion of
solid fuel in the furnace, and on the other hand by injected gases and also by the
air-blast.
The construction of the furnace in two equal halves renders it possible to reduce
the height of the same relatively to existing blast-furnaces and thereby to obviate
the disadvantages of high furnaces.
cover b.
The charging-arrangement, which serves simultaneously for closing the furnace
mouth, consists of an iron box resting partly on the partition and partly on the
walls of the furnace, and closed at the bottom by lids a and at the top by a hinged
In order to prevent the hinges of the lids and their bearings from
becoming dirty during charging, they are covered with a roof-like cover c. The
lids rest on bolts or catches e and are free to turn down or open, upon the said
bolts or catches being drawn out, whilst they are closed by means of a lever or
crank. A winch d serves for opening and closing the cover b.
During charging, the cover bis open and the lids shut, so that the circulation
of the gases in the furnace is not interfered with and their escape is prevented.
After the cover b has been closed the bolts or catches are drawn out so that
the charge lying on the lids falls into the furnace in consequence of the dropping of
the latter.
Each of the shafts A and A¹ situate on the outer sides of the furnace, is provided
with a gas outlet For F'; and each of the inner shafts B and B¹ is provided with
two small gas outlets G or G¹.
The gases escaping from the two shafts of each half of the furnace (hereinafter
termed gaseous products) pass through distributing apparatus K, K' and pipes HH'
which discharge into two gas purifiers I, I', through the inner tubes thereof,
whence they can be led off as required by pipes 24 into steam boilers, gas
generators, regenerators, roasting-furnaces, and other auxiliary apparatus, or by
pipes 25 into burners Q.
For the purpose of regulating the flow, each half of the furnace is provided
with a distributing apparatus J or J', which consists of a cylindrical box in which
a cover or valve n can be raised or lowered by a suitable lifting apparatus and
thereby the communication between the purifiers I, 1' and the gas outlets F, F¹ can
be established or interrupted.
The two halves of the furnace are connected together by a regulator P, and by
the conduit pipes 3. The regulator, which serves also as a holder for gas coming
from the generator (hereinafter termed generator gas) through the pipe 1, is
connected with the inner shafts B and B by tubes 2 that are provided with shut-off
dampers w and regulates the flow of gas from one of the halves of the furnace to
the other.

page_text: This regulator, the pipes 2, and the furnace shafts, are constructed of refractory
material and enclosed in an iron casing; the regulator is provided at the top with
a pipe o furnished with a safety valve, and at the bottom with a water pipe p for
the purpose of cooling and retaining coal and ore dust.
The entire furnace rests on hollow pillars M and N, which serve as gas conduits
and air conduits respectively. Each pillar consists of four cast iron columns g,
which are united by bolts h and nuts, and of a tube 15 or 16 of refractory material,
the corners of which are embedded in the columns. The tubes are covered
externally with brick work t from top to bottom and the spaces between the latter
and the tubes are filled up with sand in order to prevent the gases passing through
the joints of the tubes and the consequent loss of heat. The columns of each
pillar have a common support i and top piece j; on the latter rest the beams or
girders R, which are covered with cast iron plates k which carry the shafts. The
pillars M and N may if preferred be cast hollow, in which case the aforesaid
tubes 15 and 16 pass through them and through corresponding holes in the top
pieces and supports. At the bottom, the pillars M communicate with gas
regenerators by means of conduits 4 and 5, and the pillars N with air regenerators
by means of conduits 6 and 7; at the top, the former are connected with gas
jackets O, O' which are arranged around the shafts, and the latter with air conduits 8
which are arranged beneath the corresponding gas jackets.
For the purpose of enabling the gases to enter and leave, conduits 9 and 10 lead
upwards from the gas jackets and are capable of being shut off by dampers Z of
refractory material; these conduits and the gas jackets, communicate with the
furnace shafts through passages 11 or 12 respectively. Into the hearth also gas
and air supply conduits 13 and 14 open so that the gases from the conduits 4 and 5
and the air from the conduits 6 and 7 can also be introduced at the upper part of
the smelting-zone.
The conduits 4 and 6 serve moreover for connecting together the gas conduit
pillars M and the air conduit pillars N respectively of each half of the furnace.
The heating of the regenerators is effected by means of the gaseous products
which are ignited by a burner Q situate between each pair of regenerators.
Each burner, which is connected with the regenerators by conduits 17, consists
preferably of a wide horizontal tube open towards the fire space or of a shallow
gas chamber into which the gaseous products flow laterally, and in the outer
bottom plate of the chamber are inserted air supply pipes which pass through this
chamber longitudinally the inlet openings of which can be regulated by means of a
perforated slide.
The upper part of each of the hearths C and C' is situated within a cast iron
envelope or casing which is strengthened inside by ri's and the upper rim or flange
of which lies on the beams R that support the shaft.
Each hearth is connected with one of the refining-chambers D, D' by means of
a slightly inclined conduit 18 which can be closed by a slide m. These refining-
chambers are constructed in the manner of Siemens-Martin furnaces, the charging
of them being directly effected by the discharge of the fluid metal from the hearth,
and the running off of the finished cast taking place at the narrow side or end of
the refining-chamber.
Each hearth is, moreover, provided with a tap-hole y for running off the cast
iron, and above the latter with a slag hole a.
Each slide m (Fig. 6) is made of refractory material a¹ in which is inserted a
square iron rod 6 which is provided with projecting step-like shoulders 6₁₁, and is
held in place by a wedge c¹ of fire clay. This slide is at the top enclosed in an
iron frame d' which is attached to the refractory material a' by bolts e and to the
rod by bolts f₁. The upper end of the rod 61 is screw-threaded and on it is
arranged a bevel wheel j, correspondingly screw-threaded, which is prevented
from moving longitudinally and which engages with a bevel wheel ' located on the
shaft that is capable of rotation by means of the hand-wheel y', for the purpose

page_text: of raising and lowering the slide m; by means of this arrangement the
communication between the hearth and the refining-chamber is opened or closed.
To each of the gas and air regenerators Y and Z the flame from a burner Qis
conducted by the herein-before mentioned conduits 17; the flame is caused to
enter each of the two regenerators alternately by means of a slide made of
refractory material. The regenerators Y and Z instead of being furnished with
ordinary reversing valves made of iron are provided with cocks S (Fig. 3)
made of refractory material, which are better able to withstand the action of the
heat.
The regenerators for the hearths C and C' are heated by the gaseous products,
and those of the refining-chambers D D' by means of the flame and hot gases
escaping therefrom. They are in communication with injectors or fans by
conduits 19 (Fig. 3) and with flues 21 and with the main outlet conduit 22 by
conduits 20; the conduits 21 serve for heating the bottom of the hearth by the
used up gases of combustion, whereas in the outlet conduit are inserted pipes s
which serve for heating the compressed air. The air is conducted to the
regenerators through slag-pits 23 and is thereby preparatorily heated.
The refining-chambers D, D' may also be heated directly by the regenerators
belonging to the shafts of the furnace, if the gases and the air from the pillars M
and N be led into the refining-chambers whilst the flame from the opposite side
thereof be led into the flue 21, which is not, however, recommended because then
the gases are directed to one side only.
Each hearth C, C' is furnished with five holes and tuyeres q through which air
can be blown in from the air-conduit pipes L, L'. These air conduit pipes are
also in communication with pipes T, T' (Fig. 2) to enable air to be blown also into
the passages 11 which is effected by means of special tuyere-pipes r made of
graphite.
It is of the greatest importance for producing the best results, and at the same
time to enable the operation of the regenerative blast-furnace herein-before
described to be most economically effected, that the quality of the generator-gas be
such as to produce the high temperature necessary. For this purpose generator-
gas is employed which consists of a mixture of ordinary generator-gas and water-
gas, (hereinafter designated mixture gas); it is prepared in a generator of special
-construction.
This gas-generator, which is represented in Figs. 7-12, consists of two
shafts A A which are divided by a partition wall. Each shaft is provided with
an arrangement for charging with fuel similar to that described with reference to
the furnace. The gas outlets a², a² are alternately connected with the gas-
conduit C2 by means of conduits 62, 62 which are capable of being closed by slides.
Underneath the partition wall, where the two shafts unite, a steam conduit
passage discharges. Sight-holes d² and openings e² for cleaning out the cinders
and ashes and capable of being closed are provided at suitable places.
Above the gas outlets are situated small tuyeres f2, and at the broadest part of
the shaft large tuyeres g² into which enters air from the air conduit 2. Into this
conduit ² discharge also the pipes which lead to the steam passage ³.
Both of the shafts A2 are heated externally by the gaseous products from the
.generator; for this purpose vertical channels k² are provided which are connected
at the bottom with the conduit 12, which surrounds the generator on two or three
sides and heats it underneath, where it is also thoroughly heated by a burner Q,
arranged in the same way as in the furnace, and by means of the passage m².
The heating-channels k² are connected at the upper part with a passage n² for
heating the coal-holders o²; this passage has inserted for this purpose at several
places, grates p2, and communicates with the flue y through the passage q. From
the burner Q, passages, which are capable of being closed by fireproof slides s²,
lead to the regenerator-chambers B' which serve to heat the steam entering the
same through tubes 2, and can be placed in communication either with the flue y

page_text: or with the steam passage by means of the passages u³ and v³, through which
passage the steam that has been superheated in the regenerator-chambers is
blown into the generator from the pipe by means of a thin jet of air. The
alternate connection of the regenerator-chamber with the flue, or the stean passage,
takes place with the help of an elliptical valve c² (Figs. 9, 13 and 14). This valve,.
which is arranged in the cylindrical passage v² at a suitable angle to the axis of the
latter, is fixed on a rod w2, which serves for turning it; the rod w² is provided with
a hand crank x2, and is mounted in an annular bearing in the cover in such a
manner that when pressure perpendicular to the rod w² is exerted on the hand-
crank, this rod makes a certain angle with the axis of the passage v2, whereby the
partial rotation of the valve c² by the rod is facilitated, since the valve then touches
the passage walls only with those portions of its edge situated near the ends of its
short axis. When the rod of the valve has been rotated through 180° and is moved
back within its annular bearing until it again coincides with the axis of the
passage v2, the valve will then lie with the whole of its periphery in contact with.
the walls of the passage.
In this manner, in one position of the valve the communication between one of
the regenerator-chambers and the steam-passage and between the other chamber
and the flue is established, and by shifting the valve this communication is.
reversed.
The passage v2 is preferably made in a single piece of fire-clay and is placed in a
corresponding cavity in the gas generator, which is preferably surrounded by an
iron casing.
Each air regenerator, which is employed for the purpose of obviating the use of
the costly blast-heating stoves, is similar to an ordinary Siemens regenerator, but is
provided with special air-inlets in order to prevent destruction or injury produced
through the blowing in of air by means of ordinary blast-engines.
The suction of the air in this case takes place out of special regenerators by
means of injectors V (Fig. 3) made of aluminium bronze.
The injectors are worked by means of compressed air; the air, compressed by a
compressor U (Fig. 3) passes into a regulator X and thence through the tubes s to
the injectors. The atmospheric air heated in the regenerators is in consequence of
this sucked in and ascends through the conduit 19 (Fig. 3), is thus freed from dust
and brought to grates or grids of aluminium bronze which retain any solid
constituents travelling along with it. The purified air passes through openings in
the injectors, mixes there with the compressed air and is, in consequence of the
expansion of the latter ou passing through the nozzles of the injectors, compressed
in such a manner that it enters the blast-conduit with sufficient pressure, and at a
temperature of 500-600° C., to which the air must be brought for the purpose of
smelting. The force necessary for transferring the air from the regenerators into
the furnace and for overcoming the resistance in the latter is quite as great as in
the case of the application of blast-engines and stove blast-heating apparatus. The
cooling of the compressed air in the injectors is completely compensated for by
the heating of the same in the tubes s which are placed for this purpose in
the flue.
The suction and blowing-in of the air heated in the regenerators can be also
produced by means of fans, which according to the temperature to be produced, are
constructed of cast iron for temperatures up to 400° C. or of aluminium bronze for
temperatures up to 700° C. Through the compressed air of the blast-conduit is
effected, quite independently of the operation just described of the blowing in of
heated air, the blowing-in of the air out of the air-chambers of the regenerators of
each half of the furnace; the regulation of the drawn-in quantity of air is effected
in this case by means of the slides wand w¹ (Fig. 2). The atmospheric air
preparatorily to entering the regenerators is heated by the heat of the hot slag and
pieces of cast-iron which are put for this purpose into the slag-pits 23, which are
situate before each of the cocks S.
In this manner the introduction of air sufficiently heated is rendered possible

page_text: without the use of stove blast-heaters and blast-engines which however may remain
in employment if they are already provided in a plant, in which case a pair of
regenerators becomes unnecessary, and can be dispensed with.
The process of working the furnace is as follows:-
The furnace is first fed with coal and heated both internally and externally, with
hermetically closed tuyeres and blast-conduits, in order to dry the furnace. During
this time the covers or valves n of the gas-distributers J, Ji and the valves of the
gas-conduit pipes 3, and of the regulator P through which the two halves of the
furnace are in communication with each other, are opened, and the gaseous products
are free to pass through the burner Q to the regenerators.
The flame passes through the conduits 21 situate under the bottom of the
furnace, dries the furnace, and issues ultimately by the flues 22. In this manner a
uniform and quick drying is possible, the progress of which can be observed
through sight-holes in the shafts and the refining-chambers, and the completion of
which can be ascertained from the humidity of the products of combustion.
After the drying, follows the heating-up of the furnace. At the time of the
delivery of the charge (ores mixed with fluxes) it is next to be observed, according
to the size of the furnace and the number of layers, when the charge approaches
the tuyeres; if there remains below the tuyeres still room for about twenty more
charges, then a weak blast is blown into both halves of the furnace. If the descent
of the charges is uniform in the two halves of the furnace, then this shows that the
same conditions exist in the two halves of the furnace; if, on the contrary, there is
an un-uniform descent, then the operation is regulated by blowing more blast into
the corresponding half of the furnace.
As soon as the smelting-process has commenced, i.e. as soon as cast-iron appears
in the hearth, the connection between the hearths C, C' and the refining-
chambers D, D¹ is broken by lowering the slides m without, however, interrupting
the heating of the refining chambers. When a sufficient quantity of liquid pig-iron
has collected, it is allowed to flow out through the opening y beneath the slag-hole a
for the first test, by which it is ascertained whether the smelting of the cast-iron is
being conducted in the two halves of the furnace in the same and in a correct
manner. If this is the case, the cast-iron is now, by raising the slides m, allowed
to flow from the hearths into the refining-chambers, in order to be therein fined or
refined. The covers or valves n of the two gas-distributers J, J¹ are then
alternately closed for equal periods, i.e. the one remains open and consequently the
corresponding gas distributer is in communication with the chimney, whilst the
other is closed.
On this periodical changing of the covers or valves n is principally dependent
the further operation of the furnace, the motion of the gases, and the quality of the
smelted product. To particularize, air is blown through the tuyeres 9 and also
through all the injector passages 13, 14 into the half of the furnace in which
the cover or valve n is closed after the cast-iron has been allowed to run into
the refining-chamber; whereas, during this time, in the other half of the
furnace the blast is stopped and the cast-iron is retained in the hearth of this half
of the furnace by the lowering of the slide m. Instead of the blast, air, and
mixture gas from the generators, now pass into the latter half of the furnace in
order to increase the temperature therein as much as possible and to produce a
vigorous action of them on the cast-iron and the reduction of the ore. This is
effected by the help of the gases flowing in from the first half of the furnace,
which have access at three different levels by means of the open valves w
of the regulator P and of the gas-conduit 3 between the two halves of the
furnace.
At this time the fire-proof valves z of the conduits 9 and 10 must remain closed,
as otherwise the gases would flow from the gas-jacket O through these conduits
into the upper part of the shaft and thence direct to the outlet For F without
having been used up for the smelting column, whereas when the valves are closed

page_text: the gases spread through the entire smelting-column, and effect the reduction of the
layers of ore.
The mode of operation of the furnace characterized by this different motion of
the gases in the two halves of the furnace, one of these being worked with blast,
operates further as follows:-
:-
I. In the refining-chamber D of the first half of the furnace, which is shut off
by the closed slide m, the refining of the molten pig-iron previously run into it is
proceeded with in the usual manner by the introduction of gas and air, whilst into
the hearth C of the same half of the furnace, blast is blown by the tuyeres q and
the injection-conduits 13 and 14. Out of the latter the heated gases and air
from the regenerators are forced by the blast into the upper part of the hearth;
whilst the gaseous products which issue from the shaft through the outlet
passages 12, mix in the gas-jacket with the generator-gas, which reaches the gas-
jacket by the pillars M, and are blown at the top on one side into the furnace,
whilst on the opposite side the gaseous-products issue through the outlet-
passages 12 downwards and are blown into the shaft mixed with the regenerator
gas.
The preparatorily heated air led into the air-conduit 8 is blown in under the
partition wall of this shaft by the same blast. The blowing-in of gas and air is not
allowed to take place in the shaft at the same level in order to prevent a premature
smelting of the ore and to produce a reduction zone of greater height.
In this manner there are created, so to speak, two burning points in the shaft,
one in the upper part and one in the lower part, which are situated opposite the
injection-passages 11 & 14 and produce a high temperature. Between these two
points the following takes place
(1.) The reduction of the ores. This is produced by the heating of the shaft
from inside at the expense of the heat of the gases that pass through the gas
jacket O and of the heat of the air heated in the regenerator, which is conveyed
by the pillars N into the air passages 8. In order to heat the shaft from the inside
yet more powerfully, burners for burning fuel of inferior quality may be arranged
instead of the man-holes shown in the drawing (Fig. 1), so that if air of a certain
pressure is uninterruptedly blown in through the air-conduit, a constant flame is
produced by the burners.
(2.) The enrichment of the products of combustion through the presence of
glowing coal and in-blown blast, the same being decomposed and fresh heat-
producing gases thus formed.
(3.) The re-combination of the gases and the using-up of their heat in
consequence of the constant circulation of the gases from the upper to the lower
part and vice versa, until they are expelled by the gases formed in the shaft and
those coming from the regenerators.
(4.) A novel motion of the gases, since when the cover or valve of the gas
distributor of one of the halves of the furnace is closed, the gases formed by the
in-blown blast in the first shaft descend under the partition wall, travel upwards in
the other shaft, and so participate in the reactions named under (1), (2), and (3),
whereby they pass through the entire smelting layers in different directions and
effect the complete reduction of the ores; the consequence of this is that charges
can be more frequently introduced, and therefore the rate of production of the
furnace is increased, although the furnace is of comparatively small dimensions,
and a small quantity of fuel is employed.
In ordinary furnaces the conversion of the carbonic acid formed above the
tuyeres q into carbonic oxide, necessary for the reduction, in the presence of coal
made incandescent by the blast, takes place only once, because on the further quick
upward motion of the gases through the charge, the carbonic oxide is mixed with
carbonic acid and neutralized, i.e. is without effect on the reduction, which is
proved by the presence of carbonic oxide in the gaseous products, whereas in this
furnace arrangement the gases are retained a longer time in the furnace and are in
constant motion therein. In consequence of this there are constantly formed by
C

page_text: the action of the in-blown blast on the glowing coal, carbonic oxide from the
carbonic acid, and carbonic oxide and hydrogen from the steam. The decom-
position of the products of combustion takes place several times and in different
layers, whilst the coal is simultaneously changed into carbonic oxide, which change
is advantageous for the reduction of the ores.
Consequently the reduction zone is situated in that part of the furnace which is
located between the two aforesaid burning points. The heat producing gases,
which are formed by the repeated decomposition of the products of combustion in
the presence of the coal rendered incandescent by the blast, are constantly
produced with a small consumption of introduced air, and contain consequently very
little nitrogen. As the oxygen taken from these products of combustion is not
mixed with any nitrogen, much fuel is saved; whereas in the ordinary blast furnace
process, much heat is taken up by nitrogen and other inert gases.
As the carbonic oxide serves principally for raising the temperature of the
reduced cast-iron to the white-heat (1300° C.) necessary for the production of
wrought iron, for each volume of the burnt carbonic oxide, 10 volumes of the gas
must remain unburnt. This is made possible by the furnace arrangement herein-
before described, in which the following operations take place :-
(1.) The products of combustion are uninterruptedly regenerated at the expense
of the carbon of the fuel, which is brought to incandescence by the blast: that is
to say, since the combustion gases are, in consequence of the construction of the
furnace, retained in the furnace for a considerable time and are during that time in
a state of continual motion, the in-blown air can act on these gases for a longer
period of time than usual so that a repeated decomposition of the said gases takes
place at different levels, and, since the incandescent coal is at the same time
converted by the in-blown blast into carbonic oxide, the carbonic oxide thus formed
is continually brought to the decomposed products of combustion and the said
products are thus repeatedly made available for the reduction of the ores.
(2.) The semi-water-gas, which is formed in the generator and is introduced from
outside the furnace as a heat-producing gas, helps, by means of its constituent
hydrogen, to reduce the ores and to free the metal from sulphur.
(3.) The rise in the temperature of the furnace produced by the heating of the
shaft from the outside (by means of the gas-jackets O & O¹) facilitates the
chemical reactions that take place during the reduction, and during the decom-
position of the products of combustion and the re-formation of the combustion
gases.
By this continual regeneration of the products of combustion and by the
application to this reduction of the hydrogen contained in the generator-gas,
simultaneously with the external heating of the shaft, there is produced, besides
the carbonic oxide necessary for the reduction, the additional amount of carbonic
oxide found necessary by experience and which has to serve as fuel for the purpose
of producing the white-heat necessary for smelting the cast-iron.
The gases, which increase the heating-power of the fuel in the shaft in the
manner herein before described, pass into the furnace, (a) from the generators
through the regulator P which serves as a gas-holder and is connected with the
generators by the pipe I and with the shafts B & B by the pipes 2; (b) from the
regenerators Y, through the flues 13, whence they pass into the hearths C & C¹;
and (c) from the said regenerators Y, through the flues 4 & 5, the gas conducting
pillars M, the gas-jackets O & O¹, and the passages 11 & 12, whence they pass into
the shafts A & B.
The blowing-in of the blast itself serves as the motive power for producing the
circulation of the gases in the case of the half of the furnace for the time being
worked with blast; and in the case of the half of the furnace for the time being
connected with the chimney, the suction produced by the draught of the chimney
serves for this purpose.
In this manner in the half of the furnace that is worked by means of blast,
there is effected (1) the preparation of the ores and of the fuel by driving out the

page_text: hygroscopic water and the products of distillation; (2) the mixture of the furnace
gases with the generator gases, which latter consist of a mixture of ordinary
generator gas with water-gas; (3) the reduction of the ores; (4) the regeneration
of the products of combustion; (5) the carburisation of the reduced iron;
(6) the formation of the gases out of the solid coal; and (7) the smelting of the
cast-iron.
II. In the second half of the furnace, which is exposed to the suction of the
chimney through its connection therewith, the more or less heated gases that pass
over from the first half of the furnace through the regulator P, give up their heat,
flow, in consequence of the draught, out of the first shaft B' under the partition
wall into the second shaft A', reduce thereby the ores, and escape into the gas-
outlets FG. At the same time very highly heated gases and air are drawn into
the hearth C¹ from the regenerators, which gases and air produce, on burning, a
temperature of about 2200° C., which is rendered possible, firstly, by the peculiar
nature of the gas produced in the generators, and secondly, by the circumstance
that all the other re-actions take place in the first half of the furnace.
In consequence of this high temperature, no carburisation of the iron takes
place as in the first half of the furnace, in which a considerable cooling occurs in
consequence of the decomposition of the products of combustion, but the reduced
iron sponge passes into the hearth and is dissolved there in the previously smelted
cast-iron, whereby a partial decarburisation of the cast-iron is produced and the
mass is converted into a thick fluid.
As soon as this occurs the reversal of the working action of the furnace must
be effected by reversing the covers or valves n in the gas-distributors J J', and the
smelting of the cast-iron, and of the ores, is then proceeded with in the second half
of the furnace in the manner hereinbefore described with reference to the other
half. By this means the metal becomes carburised and consequently fluid; and a
steel-like mass is obtained which is allowed to flow into the refining chamber D¹
(together with the slag) for the purpose of being refined. During this time, in
certain cases, scrap-iron of different kinds can be added to the refining chamber D'
after being preparatorily heated. The refining chamber is then shut off from the
hearth by again lowering the slide m and the entire contents of the refining
chamber refined at a high temperature produced by the burning of the mixture
gas. By the introduction of suitable alloys the desired nature is given to the
metal.
In the hearth of the same half of the furnace, after the reversal of the covers
or valves, the smelting of the cast-iron is proceeded with in the same manner until
the reversed operation is caused to commence in the other half of the furnace by
reversal, and so on.
In case the cast-iron is to be smelted in both halves of the furnace simultaneously,
the connection between the hearths and the refining chambers is broken and heated
blast is blown into the tuyeres of both halves of the furnace. At the same time
the refining of the products obtained can be proceeded with in the refining
chambers and the heat therein generated be used for heating the furnace hearths
at the bottom and at the slides m.
Such a working of the furnace is useful if, notwithstanding the careful execution
of the operations, the fluid metal should become viscous and form bears and crusts,
which occurrence may be caused for example by the cooling of the regenerators
and the consequent cooling of the hearths. In this case, the covers or valves of
the gas distributors J, J and K K' are opened and blast is blown in through
all the tuyeres whereby the metal is again made liquid.
The gases and air thus blown in are not lost, but still further promote the
smelting.
The gaseous products in excess are employed for the heating of all the
auxiliary apparatus, whilst the bears and crusts are dissolved by the ample
production of slag and cast-iron; also the freezing of the furnace need not be
feared.

page_text: The mode of operation of the gas generator employed in the hereinbefore
described method of furnace-working, for the production of the semi-water-gas or
mixture gas is as follows:-
In the divided shaft of the same, the blast is alternately introduced at certain
intervals into the one or the other half A' from the top and from the bottom.
During this time the slide of one of the gas-outlet conduits a³ is closed and the
other open, so that the latter is in communication with the gas-conduit C. In the
air-conduit situate above the gas-outlet conduit, the slides are arranged in
the reverse manner. In consequence of this the one half of the shaft is heated,
the volatile constituents and the moisture of the coal are driven out by means
of the blast through the top tuyeres f2, whilst the resulting distillation-products
are consumed at the lower tuyeres g². Simultaneously in the other preparatorily
heated half A2 of the shaft there is proceeding in the presence of glowing coal,
the decomposition of the carbonic acid and of the superheated steam, which is
introduced by means of the blast through the conduit j. The gas from this half
of the shaft is ready for use. The superheating of the steam takes place in the
regenerator chambers B2 which are situated under the shaft and are heated by the
gaseous products from the furnace.
In order to increase the energy of the re-actions proceeding in the gas generator,
the latter is as hereinbefore stated, heated externally by the escaping gases which
pass through the passages l², k², n², m² and heat the walls of the generator, the heat
from these passages together with that from the regenerators B2 serving to heat
the bottom of the gas generator, and also to dry the coal contained in the coal-
holders o².
When in consequence of the formation of the semi-water-gas or mixture gas the
cooling of the corresponding half of the generator commences, the slides are
reversed and the same process is commenced in this half as formerly took place in
the other half; viz. dry distillation, the heating of the coal, the burning of the
distillation-products at the lower tuyeres, and the formation of the gases, whilst in
the other half of the shaft the decomposition of the products of combustion and of
the steam is proceeding. The mixture gas produced is led away into the furnace
and effects by the production of a high temperature the herein before mentioned
re-action. The hereinbefore described regenerative blast-furnace may be constructed
of such a size as to be suitable for smelting other ores the layers of ore and fluxes
being then selected so that any iron contained in the ore goes into the slag. In
one half of the furnace the raw ore is smelted, whilst in the other half of the
furnace the pure metal is obtained from the products of the smelting in the
first half.
By the alternately or simultaneously conducted reduction and oxidation of
the products of the smelting operation, the sulphur and the iron are removed from
the same; whereupon the metal is freed from oxides by stirring in the refining-
chambers, which are shut off from the hearth.
This furnace offers therefore the following advantages
(1.) The working can be carried on in the two halves of the furnace as desired.
by means of the gas-distributing apparatus by reversing the flow of the gas, and
thus the reduction and oxidation processes can proceed in the two halves of the
furnace according to requirement either simultaneously or alternately.
(2.) The gases enriched in the shafts can be mixed with the semi-water-gas or
mixture gas heated in the regenerators, and be uninterruptedly employed for the
metallurgical processes.
(3.) The quantity of fuel used in the interior of the furnace is reduced by the
uninterrupted external heating of the furnace-shafts and at the same time
the re-actions are accelerated.
(4.) The furnace can be more frequently charged, i.e. a large production can be
obtained with apparatus of comparatively small dimensions.
(5.) The heat of the hot slag and of the cast metal is supplied to the furnace
when it commences to cool.

page_text: (6.) By the motion of the gases in the furnace in different directions their heat
is completely utilized; and as they are blown in by means of the blast and the
oxygen of the products of combustion is used up, smaller quantities of blast and
fuel are necessary, and by the formation of the necessary quantity of carbonic oxide
the iron is protected from the action of the carbonic acid.
(7.) By the drawing-in of the gases and air, a high temperature, which prevents
carburising, is produced in the half of the furnace which is connected with the
chimney and in which the refining is taking place.
(8.) The blowing of hot blast of adequate pressure into the furnace can be
effected in a simple and economical manner.
(9.) The production of wrought-iron is possible without any loss of heat, since
the smelted pig-iron is run direct from the furnace-hearths into the refining--
chambers.
(10.) The two halves of the furnace can be worked independently of each other,.
and one half can when required, be put entirely out of action.
(11.) Smelting-products of various kinds can be produced; e.g. by working iron-.
ores, cast-iron, wrought-iron, or steel can be produced.
Metal of good quality is produced by means of this furnace, an economy of
gaseous and solid fuel being obtained, which may be further increased if the heat
which is lost by the cooling of the hearth is made useful, which may be effected by
lining the walls and bottom of the hearth with carbonaceous bricks, or with
magnesite. This lining with magnesite may also be provided in the refining
chamber, in which case the same is inlayed with a basic addition for the purpose
of de-phosphorizing the ores, as an isolated layer between dinas-bricks and
dolomite.
Having now particularly described and ascertained the nature of the said inven-.
tion and in what manner the same is to be performed I declare that what I.
claim is :-
1. The herein described method of obtaining metals direct from their ores with
the simultaneous and uninterrupted production of smelting-products of different
kinds, according to which the smelting of the ores is effected in a regenerative
furnace made in two halves adapted to be placed in communication with each other
and each of which consists of two shafts having a common hearth and a refining-
furnace adapted to be placed in communication with such hearth, one half of the
furnace being first worked as a blast or reducing furnace into which air is blown in
different horizontal planes for the purpose of producing a continuous reduction,.
whilst the other half of the furnace, which for the time being is connected with the
chimney, is worked as a decarburising furnace by the hot gases escaping from the
first half which are drawn into it together with heated combustible gases and air
from regenerators in order to produce a sufficiently high temperature to effect the
decarburisation of the metal previously produced in it when acting as a blast or
reducing furnace, after which the decarburised metal is run off, it may be into the
corresponding refining furnace, and the direction of the gas through the two
halves of the furnace is reversed, so that the secondly mentioned half becomes the
reducing one, and the first mentioned half the decarburising one and so on as set
forth.
2. For obtaining metals in the manner referred to in the preceding claim, the
herein described method of continuously producing a mixture-gas consisting of
generator-gas and water-gas by blowing air and superheated steam alternately into
the top and the bottom of each of the two shafts in turn, of a divided gas generator
charged with carbonaceous fuel such as coal, so that during the simultaneous
heating of the said generator externally by the gaseous products escaping therefrom
there is effected in one half of the shaft, the heating of the coal, the combustion of
the products of distillation, and the formation of gas, and in the other half of the
shaft the decomposition of the products of combustion and of the steam substantially
as described.

page_text: 3. For carrying out the method specified in Claim 1, a double regenerative-blast-
furnace, comprising two pairs of shafts A B & A¹ Beach pair being separated
above their common hearths C or C¹ by a vertical partition-wall f, and being
carried by tubular gas and air conducting pillars M & N which connect the furnace
with a source of heat, refining-chambers D'D', each arranged to be placed in direct
connection with the corresponding hearth C or C' by a passage controlled by a
slide m, gas-distributing apparatus J, J' connected with the upper ends of the pairs
of shafts, and a regulator P with passages connecting the pairs of shafts and
serving at the same time as a reservoir for gases coming from a gas generator, the
arrangement being such that the flow of the gases coming from the gas generator
and of the gascous products produced in the said shafts, can be simultaneously
controlled by slides w arranged in the regulator P, and the connection between the
hearths C, C and the corresponding refining-chambers, can be controlled by the
slides m, so that the two halves of the furnace can be worked in series, or each half
of the furnace with its refining-chamber can be worked independently of the other
half, and each refining-chamber independently of the furnace-hearth belonging
thereto, substantially as herein described.
4. The combination with the furnace specified in the preceding claim, of a gas
generator having two shafts A2, A2 that are separated by a vertical partition, are
adapted to be placed alternately in communication with a gas-conduit C2, and are
provided with tuyeres f2 and 92 for the introduction of air, with a steam-conduit j²,
and with external heating conduits k², 12, n², m² and regenerator-chambers B³ for
the purpose of superheating the steam used in said shafts, these regenerator
chambers being capable of being placed alternately in communication with the
steam-conduit of the generator and with the exit flue by conduits u², v² controlled
by an inclined elliptical valve c², substantially as described and shewn.
5. The combination with the furnace specified in Claim 3, of an air regenerator
into which air is drawn from regenerators in an already heated condition, by means
of injectors or equivalent devices worked by air compressors substantially as herein
described.
6. For controlling the communication between the furnace-hearth C or C¹ and
the refining-chamber D or D¹ referred to in Claim 3, a slide m consisting of a
body a' made of refractory material and adapted to be raised and lowered by a
rod 6' which is inserted in it and is formed with step-like projections, substantially
as described.
7. The combination and arrangement of parts constituting the improved apparatus
herein before described with reference to and shown in Figs. 1 to 5 inclusive of the
drawings annexed for producing metals direct from their ores in the manner set
forth.
Dated this 24th day of October 1893.
W. F. BERNER,
By L. W., per F. B.