IMPROVEMENTS IN THE CONSTRUCTION OF FURNACES FOR THE MANUFACTURE OF COKE, DISTILLATION OF GAS, AND TAD
Year: 1880

page_text: LETTERS PATENT to George Alexander Dick, of 110, Cannon Street, in the
City of London, for an Invention of "IMPROVEMENTS IN THE CONSTRUCTION
OF FURNACES FOR THE MANUFACTURE OF COKE, DISTILLATION OF GAS, AND
TAD
PROVISIONAL SPECIFICATION left by the said George Alexander Dick
at the Office of the Commissioners of Patents on the 9th October 1880.
GEORGE ALEXANDER DICK, of 110, Cannon Street, in the City of London.
"IMPROVEMENTS IN THE CONSTRUCTION OF FURNACES FOR THE MANUFACTURE OF
COKE, DISTILLATION OF GAS, AND FOR OTHER SIMILAR PURPOSES."
This Invention consists in improvements in the construction of furnaces by
means of which the manufacture of coke, distillation of gas, and other similar
operations can be effected in a continuous manner.
In furnaces and arrangements of apparatus as ordinarily constructed for effecting
the manufacture or distillation of solid, liquid, or mixed materials, such as zinc,
sulphur, illuminating gases, ammonia, tar, coke, charcoal, and wood, the charging is
effected from time to time, but always intermittently and without the application
of any mechanical feeding arrangement. All of such furnaces or arrangements of
apparatus consist of one chamber only, such as a retort, muffle, or other contrivance
or receptacle in which the distillation takes place, and in which the solid products
remain after the completion of the process of distillation until they are removed to
make room for fresh material, thereby necessitating the interruption of the working
of the furnace or apparatus. This changing is generally effected by hand, the
fresh material being only introduced after the old material has been entirely
removed.
The loss of time and interruptions attendant upon the employment of the above
described arrangements are entirely avoided by the improved furnace, forming the
subject of this Invention.
The furnace consists of one or more chambers constructed in one piece or built
up of fire brick or other suitable material according to the nature of the substance
to be treated, and arranged horizontally, or in any convenient position. These
Dmin1

page_text: chambers are surrounded by a number of flues or channels of fire brick for the
circulation of the heating medium, which is obtained or generated by any suitable
means. The outer ends of the said chambers are provided with hoppers and screws,
or other contrivances, for the purpose of mechanically effecting and regulating a
continuous supply of the material to be treated, and the inner ends open into a
chamber (hereinafter referred to as the evacuating chamber) provided for the
reception of the gases, coke, or other substances after the completion of the process
of distillation or sublimation. The last mentioned chamber may consist of several
separated chambers, or of one common chamber only, and is provided with an
opening or openings at the upper part for the exit of the volatile products, a series
of openings provided with doors capable of being hermetically closed, being
arranged at the lower part of the said chamber for the extraction of the solid and
liquid products of the process. The distilling chambers are so formed as to
gradually increase in size from the outer ends to the inner ends for the purpose of
facilitating the action of the screw or other feeding contrivance in forcing forward
material being acted upon and also to accommodate any expansion of the latter
from the action of the heat, and I prefer to effect this object by causing the
bottoms of the chambers to incline inwards.
The action of the apparatus is as follows:-The material to be operated upon is
placed in the hoppers, and is caused to enter and advance gradually and continually
along the distilling chambers by the feeding mechanism, and after the required
degree of heating and distillation has been effected the products escape into the
evacuating chamber. Either the gaseous, liquid, or solid products, can be utilised as
the heating medium when the other products are alone considered of value, or
failing any of these, fuel of any suitable nature may be employed. The volatile
products of distillation, for instance, illuminating gas, ammonia, creosote, paraffin,
chloride of zinc, and sulphur, pass, as already indicated, from the distilling chamber
into the evacuating chamber, and thence through the opening or openings herein-
before referred to into a receptacle or apparatus to be cooled, purified, or otherwise
treated as desired. The solid products, such as coke, oxides of metals and charcoal
fall from the distilling chambers, which always remain filled with the material
being acted upon, into the evacuating chamber, and when it is desired to remove
them therefrom the opening or openings for the escape of the volatile products is
or are closed, and the pressure of the latter thus brought to bear on the solid
products assists in the extraction of the same. The doors of the evacuating
chamber can be opened one after the other, so that the solid products are removed
without atmospheric air being admitted to the said chamber, and without the
necessity of interrupting the process of distillation or sublimation.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, and of
an Order of the Lord Chancellor, filed by the said George Alexander Dick in
the Great Seal Patent Office on the 20th April 1881.
GEORGE ALEXANDER DICK, of 110, Cannon Street, in the City of London.
"IMPROVEMENTS IN THE CONSTRUCTION OF FURNACES FOR THE MANUFACTURE OF
COKE, DISTILLATION OF GAS, AND FOR OTHER SIMILAR PURPOSES."
My said Invention consists in improvements in the construction of furnaces, by
means of which the manufacture of coke distillation of gas, and other similar
operations can be effected in a continuous manner.
In furnaces and arrangements of apparatus as ordinarily constructed, in which
solid materials, such as, for instance, zinc ores, sulphurous minerals, combinations
of carbonic acid, coals, brown coal, peat, slate, wood, or mixtures of these materials
with others are subjected to heat for the purpose of effecting the distillation or
sublimation of solid, liquid, and gaseous products, for instance for the production
of chloride of zinc, sulphur, carbonic acid, gases for lighting or heating, wood
spirit, ammonia, wood vinegar, creosote, tar, paraffine, charcoal, coke and caustic
oxides of earth and of metals, the charging is always effected in an intermittent
manner. In such furnaces or arrangements of apparatus there exists only a single
space, namely a pipe, the retort, the furnace, or other contrivance or receptacle in
which the process is effected, and in which the solid products of the distillation or
sublimation remain until they are removed in order to make room for new material,
thereby necessitating the interruption of the working of the furnace. The removal
of the said solid products is generally effected by hand, and the fresh material can
only be introduced after the said products have been completely cleared out of the
apparatus.
The great loss of time and frequent interruptions to the working entailed by the
employment of the said furnaces or arrangements of apparatus are entirely avoided
by the improved furnace forming the subject of my said Invention, which is
constructed and arranged as follows:-
:-
One or more distilling chambers constructed of one piece or built up of fire brick
or other suitable material according to the nature of the materials to be treated are
arranged horizontally or in any convenient position; These chambers have arranged
around them a number of flues or channels for the circulation of steam, heated
products of combustion or other medium employed for heating the said chambers,
and effecting the distillation or sublimation of the materials contained therein.
The outer ends of the said chambers are provided with hoppers and screw
arrangements or other suitable contrivances for the purpose of mechanically
effecting and regulating a continuous feed to the said chambers of the materials to
be treated. The inner ends of the distilling chambers open into a chamber (herein-
after referred to as the evacuating chamber) provided for the reception of the
gases, coke, or other products of distillation or sublimation. The whole of the
distilling chambers can be arranged to open into one evacuating chamber, or several
evacuating chambers can be employed, one or more of the distilling chambers
opening into each of them. The evacuating chamber is provided with an opening
or openings at the top for the exit of the volatile products, and a series of drawers
constructed to close hermetically are arranged at the lower part of the said chamber
for the extraction of the solid and liquid products, but, when desired, pipes, com-
municating with the lower part of this chamber are provided for carrying off the
liquid products. The distilling chambers can be arranged in one or more rows,
and they may be of any shape suitable to the varying requirements, but by
preference I construct them with diverging sides, so that the size of the said
chambers will gradually increase from the outer ends to the inner ends, this

page_text: arrangement facilitates, the action of the screw or other feeding contrivance in
forcing forward the material being acted upon, and it also provides accommodation
for any expansion of the latter from the action of the heat. In this arrangement
it is desirable that the top of the chambers be horizontal, but the bottom is inclined
inwards.
I will now proceed to refer to the accompanying Drawings, Sheets I. to VIII.,
from which the nature of my said Invention will be more clearly understood.
Sheet I., Figure 2, are horizontal cross sections of the (furnace) through the lines
7, 8, 9, 10, 11, 12, in Figure 1; Figure 1 are vertical sections through the lines
1, 2, 3, 4, 5, 6, in Figure 2; and Figure 6 is a section through the line 21, 22, 23,
in Figure 1. The same letters of reference indicate like parts in all the Figures of
Sheets I., VIII. A are the chambers in which the distilling or sublimation is effected;
d, e, f, g, are the flues or channels provided for the circulation of the heated gases,
steam, or other medium employed for effecting the desired object. The materials
of the walls separating the chambers A from the flues d, e, f, g, should be made as
thin as is consistent with the requisite strength; Bare the mechanical contrivances
for effecting the charging of the chambers; E is in Sheet II., Figures 18, 19, and
20, the evacuating chamber, the opening for the escape of the gaseous products of
distillation or sublimation is shown at a, and the doors for the extraction of the
solid products are shown at F.
The action of the apparatus is as follows:-The material to be operated upon is
placed in the hoppers or other equivalent contrivance, and is caused by the action
of the feeding mechanism to enter and travel gradually and in a continuous stream
along the chambers A. During the passage of the material through the said
chambers the distillation or sublimation is effected, the gaseous products thereof,
for instance, illuminating gas, ammonia, creosote, paraffine, chloride of zinc, and
sulphur, pass, as already indicated, from the chambers A into the evacuating
chamber E, and thence through the opening or openings hereinbefore referred to
to any suitable receptacle or apparatus to be cooled, purified, or otherwise treated,
as desired. The solid products, such as coke, oxides of metal, and charcoal, fall from
the inner ends of the chambers A, which always remain filled with the material being
acted upon to the lower part of the evacuating chamber E, and when it is desired
to remove them therefrom, the opening or openings c, for the escape of the volatile
products is or are closed, and the pressure of the latter thus brought to bear on the
solid products assists in the extraction of the same. The doors F of the evacuating
chamber can be opened one after the other, so that the solid products are removed
without air being admitted to the said chamber E, and without the necessity of
interrupting the process of distillation or sublimation.
The requisite heat for effecting the distillation or sublimation can be obtained by
the utilization of gaseous products of the said processes, so far as they are
combustible, but if value be placed upon them, the fluid or solid products, so far as
they are combustible, may be employed for the purpose, providing they are not
otherwise required. However, if none of the products be combustible or available
the necessary heat can be obtained by the employment of steam, superheated-steam,
hot air, or other suitable and known medium.
The following are detail descriptions of the arrangements for the special
applications of the said Invention:-
I will now proceed to describe the application of the said Invention to gas
expelling chambers for generators and apparatus for distillation and sublimation.
The gas expelling chambers of the generator with separate gas expelling and
converting chambers are not only constructed in one piece, but may also be made
of small fire bricks of the usual size, in conformity with the arrangement as drawn
in Figure 1, in such a manner that the floors and sidewallings may be made of the
smallest dimension of the shape of brick which is to be employed at the time.
The shape of the gas expelling chamber, that is the length, width, height, and
the divergence of the side wallings, depends upon the coking capability, that is to
say, the qualities of the coal to be employed.

page_text: The surroundings of the gas expelling chambers consist of trellis brickwork, as
drawn in Figure 1, constructed of fire bricks of the usual size, which serve to
support the gas expelling chambers, and form at the same time the flues N for the
circulation of waste heat.
Improved methods for the firing arrangements and generators which permit, as
may be desired, in combination with sliding registers cooled by water, ventilators,
or similar arragements, the distribution of the heat from the fire, or of the gases
from the generators, either in the place where the heat is to be used in the furnace
or under the steam boiler, are drawn in Figures 2 and 3.
Hitherto there has not been employed with the generators which are near the
places where the heat is to be used, and with the ordinary grate fires, any means
for increasing or diminishing the quantity of gas or heat which is to enter direct
into the furnace.
No separate means existed of conducting the gas from the generator to an
existing steam boiler, nor was there any possibility of increasing the quantity of
gas or of heat which was to enter the steam boiler direct, if it was required that
the heat necessary in the furnace had to be diminished, or vice versa.
With the Siemens generators, which, because of their distance from the place of
consumption, completely cool the gases, there only existed the possibility of
employing side valves and ventilators made of cast or wrought iron, which were
not cooled. If one desires, however, to avoid the losses resulting from the arrange-
ment of the Siemens generators, which amounts to forty per cent. of the possible
heat, or if it be desired to place the generators close to the place of combustion
other means for effecting the desired object must be employed.
Whenever steam boilers are fixed behind the place where the heat is to be used
(in steel heating, welding, and puddling furnaces) the means of regulating the
quantity of heat in the same consisted only in the chimney valve made of cast iron,
because being situate between the steam boiler it was only acted upon by the
products of combustion, heated to two hundred or two hundred and fifty degrees.
If one is, however, compelled to close this chimney valve, for instance, when the
parcels of steel or iron are sufficiently heated without being able to take them
out of the furnace the gas blows out from all the doors and openings of the fire
place, of the generator, of the furnace, and of the boiler, unburnt and unused so
long as the valve has to remain closed.
This consequently again gives rise to great losses, which constantly and regularly
occur.
At places where heat is used but where no steam boiler arrangements are
employed, for instance, glass furnaces, no means whatever exists for regulating the
quantities of gas or heat necessary in the furnace, because neither metal valves,
which are not cooled, nor such as are made of fire proof material are possible between
the source of the heat (the generator or the grate fire) and the place of consumption
(the furnace).
With glass furnaces it is necessary, for instance, after the melting, that is to say,
the clarifying of the glass, to cool, in order to render the glass fit for manufacturing
purposes. This cooling of the furnace, that is to say, of the pots, requires
many hours at present (causing a loss of time), and involves enormous losses of
fuel.
If one is however in a position to regulate the quantity of heat which enters the
combustion chamber at any time and rapidly, which can only be effected by sliding
registers cooled by water, most extraordinary advantages in the working of the
various industrial branches will be obtained.
The Drawings 2 and 3 show various combinations (of furnaces for various
industrial branches with generators or firing arrangements) which render it possible
that the gases can enter completely or partially into the furnace as well as completely
or partially into the air heater, or also completely or partially into the steam
boiler.

page_text: For the regulation of the quantities of heat or gas the sliding registers cooled by
water and marked h, h¹, h², are always serviceable.
It being well known that if these parts are made in hollow cast or wrought iron
they will not last, I wish to point out particularly that I produce such parts by
casting iron around iron gas or water tubes, which have been bent accordingly and
made to fit into moulds of corresponding shape.
The generators may be of any construction, consequently they need not be like
those shown in the Drawings.
The heat can also be produced by any desirable fire arrangements of other
construction.
The air heaters as well as the steam boilers may be of any desired construction.
If the source of the gas or heat be at A, as is the case in the Drawings 2 and 3,
the heat or gas is conducted completely or partially into the furnace C through the
flue g, g, which is regulated by the sliding valve h cooled by water, and then into
the steam boiler or into the chimney through the flues g, Drawing 2, and g²,
Drawing 3, which are regulated by the sliding valve g³, that is to say, g², completely
or partially through the air heater or generator.
If any gas circulates in the flues g³, Drawing 2, and 93, Drawing 3, care is taken
that it meets with hot air in the chambers n¹, Drawing 2, or n³, Drawing 3, for the
most advantageous combustion.
These arrangements are also of particular advantage in cases where gas is to be
produced from cheap coals, and where therefore regard may be had to the heating
of the steam boiler only through this generator.
In this case a possible excess of gas is allowed during the working of the furnace
to proceed through the flues g³, Drawing 2, and g², Drawing 3, into the chamber n¹,
Drawing 2, and n², Drawing 3, and then being regulated by the sliding valves h,
Drawing 2, and h², Drawing 3, into the chambers nº, nº, n10, Drawing 2, n³, n³,
Drawing 3, and thence below the steam boiler.
Generally in furnaces worked as welding, heating, or glass making furnaces, the
waste heat possesses such an excess of oxygen that these gases are burnt completely
in conjunction with the same (oxygen).
In the other case the requisite quantity of heated air is allowed to enter also in
the chamber n¹, that is to say, n².
In the event of not working the furnace, the quantity of gas which is requisite
in order to keep the generator working, and which has to produce the heat necessary
for expelling the gas, enters likewise by means of the sliding valve h¹, Drawing 2,
h², Drawing 3, into the room n', that is to say, n², after the sliding valve h has been
closed.
Drawings 4 to 14 show beams cooled by water for firing arrangements and
generators.
The usual grate fire arrangements admit the air at one place, the gas fire
arrangements admit it at two places.
The place where air is admitted is always however also the bearer of the fuel to
be oxydised and also the place for discharging the slags.
Until within a few years only the innumerable constructions of grate arrange-
ments served for this purpose.
Siegel at first reduced the size of the grate arrangements to a minimum by
narrowing the room for the fire to a horizontal slit, under which he considered it
still necessary to have an auxiliary grate.
Since then the arrangements of the slits have experienced many different
alterations, and they have already superseded a great many grate arrangements.
The objects of the arrangements drawn and described are,
1. The doing away with grate constructions by the introduction of slits, which
are more suitably constructed than hitherto, and which serve at the same time and
without any auxilliary grate for admitting the air and for carrying off the
slags.

page_text: 2. The procuration of the unvarying dimensions of the places admitting the air
by limiting these slits by means of cast iron beams cooled by water.
3. The establishment of a simple contrivance for completely closing up the place,
admitting the air in firing arrangements and generators of every kind.
The Drawings represent the front view of the arrangements in the sketches 4, 10,
and 13; the sketches 5, 8, 9, and 11 represent perpendicular sketches; and the
sketches 6 and 7 horizontal sections.
If the slit be horizontal it cannot be watched; the slaga accumulate in the whole
extent of the slit; the quantity of the same in the separate places cannot be watched
over, and their removal is from these reasons rendered difficult.
It is true that if the slit be made to slant from the front to the back the power of
controlling it is great; the slags however run all towards the cold back wall, take
a firm footing there, and are very difficult of removal.
The slit B for air and for slags, which in the Drawing is only represented by a
cast iron beam L cooled by water, is made to slant from the front and the back
towards the middle of the fuel for the purpose of watching the slit easily in the
first instance, and also for making the slags run together towards the middle, whence
this being the hottest place they can be easily removed.
In the Drawings sketches 4, 5, 6, 7, 8, 11, and 13, the slit is assumed to be
attended to on one side, but it may still be better attended to from two sides, see
the sketches 12, 13, and 14. Into the beam L a wrought iron gas pipe bent to
correspond has been cast, which causes the water to circulate in the order indicated
by the figures.
It being well known that if these parts made in hollow cast or wrought iron will
not last, I wish to point out particularly that I produce such parts by casting iron
around iron, gas, or water tubes which have been bent according and fitted into
moulds of corresponding shape.
If the slits are constructed as hitherto of firebricks, their width, by which alone
the admission of air and the discharge of the fuel is limited, is dependent upon the
kind of slag and upon the attention of the stoker, that is to say, the man attending
to, the heating.
If the slag be of a thin fluid nature it eats away the fire bricks, and thus
enlarges the slit; if the slag be of a thick fluid character it adheres firmly to the
firebricks, pieces of which are constantly knocked off, whenever a cleaning takes
place, so that the slit is very soon unduly enlarged.
With the enlargement of the slit the quantity of the air admitted is changed
and a larger discharge of fuel takes place which therefore involves a loss.
All these evils are avoided by using the slits, cooled by water, as described.
The slags do not adhere firmly to the sides of the cooled slits and they can
therefore be very easily removed.
The width of the slit C is arranged according to the shape of the combustible
material and the power of the draught.
Many of such slits, formed from one or two beams L cooled by water may be
arranged side by side in one fire arrangement.
The conduits of water of three, four or more of such cooled beams may be
connected with each other, without the water getting too hot.
The beam C cooled by water serves for the maintenance of the sides of the fire
arrangements and generator.
The disposition of the coolings described for various arrangements of the oxydising
chambers for the combustible material of various kinds of fuel is indicated in the
Drawings.
The sketches 4 to 8 shew the application with slits, running from the front to
the back, and so be attended to from one side; if these slits are to be attended to
from two sides the arrangement shewn in the sketch 14 is applied.
The sketches and 10 demonstrate the application of coolings in chambers for
oxydising fuel which are provided with grates.
The sketches 11 and 13 shew the application of coolings with slits served on one

page_text: side, and running from one side to the other; if these slits are to be attended to
from two sides the arrangement as shown in the sketches 12 and 14 is employed.
In the beam C there may be a place d, sketches 4 and 5 through which a sham
gate may be made and in which the fuel may be caught up in the event
of a special cleaning becoming necessary after a prolonged suspension of the
working.
The arrangement drawn, which is to serve the purpose of completely shutting off
the admission of air from fire arrangements of every kind, consequently also from
generators during the stoppage of the working, is the following one:-
In the frame M, sketches 4 and 8, there are hooks rivetted in, on which the
iron Orests which bears during the working the arrangement for removing the
slags.
In the sketch 4, the iron O is shewn in an interrupted manner, whilst in the
sketch 6 it is completely shown; these sketches show the condition during the
working.
The frame M is further provided with ribs below, which therefore form a swallow-
tail-like gutter. The moveable door N has a handle and a rib, which fits exactly
into the gutter of the frame M.
If the working is to be suspended the gutter of the frame M is plastered over
with a plastic loam or clay; the movable door N is placed in such a manner that
its rib passes into the loam or clay, the iron O is bolt like placed before it, and the
door N is driven to by means of a wedge.
The sketches 7 and 8 show the condition of the fuel during stoppage.
By means of this arrangement as drawn and described, a simple method, which
may be rapidly applied for the purpose of shutting off the air hermetically is s
established.
The following is a description of the apparatus for heating the air.
One of the evils of the air heaters, as used hitherto for generators or fire arrange-
ments (Ponsard Nekse) is that communications are formed between the flues for air
and for heat.
If the side walls and ceiling of the heating flues which are running horizontally
and parallel to the flues for heating the air, have been made of large thin plates,
the side walls will become loosened from the following reason :-
Such large, thin, fireproof plates cannot be formed direct and burnt in so exact a
manner that their surfaces do not become distorted.
These can certainly be worked if ready burnt, but it is very difficult and by far
too expensive to join them really one upon the other, that is to render them per-
fectly tight; this is just as difficult as if the tightening is done by means of folds,
tringles, and grooves or dowels.
However, if the large plates could even be joined closely one upon the other, they
would, on account of their size and because they could not be uniformly burnt
through, soon become distorted from the heat, and this would occur all the more
easily since they are heated strongly on one side by the hot combustible gases,
whilst they are strongly cooled on the other side by the cold air.
If the separating walls between the horizontal and parallel air and heat flues are
only made of walls half a brick in thickness their height is a very limited one; the
construction is a very difficult one, because they tumble down whilst being built,
and therefore the tightness of the walls is inconsiderable. If the separating walls
are however made (like those constructed by Ponsard from small bricks of the
usual shape or from special or figured bricks, in any case however of small (edge a
ways) dimensions, a want of tightness of such separating walls cannot be at all
avoided, but is sure to occur. In all these cases the working of smelting furnaces
and other furnaces which are provided with gas-heating and consequently with air
heaters is impossible, as proved in practice.
As soon as the unavoidable communication between the air and waste heat flues
running side by side takes place the air passes through the shorter way of the
waste heat flues to the chimney and does not enter any more into the furnace, the

page_text: gas which enters the furnace receives therefore no air, and it passes unburnt
through the furnace into the waste heat flues.
By this however the purpose aimed at, the developement of heat, the smelting
process, and other operations, is rendered impossible. If now the working be not
interrupted, because the seat of the disturbance was not instantly found, the gas
meets the air, which streams towards the chimney through the crevices in the
separating walls in the waste heat flues of the air-heating! apparatus, is burnt
together with it, and produces so high a temperature that the entire heating
apparatus melts into one mass.
In the accompanying Drawing, sketches 15 to 22 of the improved arrangement
of air-heating apparatuses, the separating walls of the chamber n' are 1 brick in
thickness, and consequently so strong that they can be built up by themselves to
a considerable height without losing their hold, that is to say, without losing in
tightness. Besides, with this brickwork of the thickness of 1½ brick, all quarter
bricks, all useless joints are avoided thereby, that the air-heating shafts o¹ which
are in the separating walls of the heating chambers n' are made equal to a three-
quarters piece of the shape of bricks employed, or equal to a multiple of such
three quarters pieces. Only this arrangement permits the exclusive employment of
whole bricks of the usual shape in most excellent conjunction with each other,
diminishes the joints, produces a very stable kind of brickwork, and ensures the
tightness of the separating walls.
The connexion to be applied for the construction of these separating walls is
represented by the sketches 18 and 19 for two layers.
The height of the chamber n' has remained limited here in order not to allow
the Drawing to become larger.
With more elevated heights a number of supporting arches or layers at various
levels may be arranged ad libitum.
As many such air heaters as may be desired can be constructed side by side.
In order to render an even settlement of the brickwork of the air heater possible,
it is, as drawn in sketches 16 and 17 of the Drawings, not constructed in con-
nexion with the outer walls, but there remains between both an intermediate space
of several centimetres, which is filled up with dust of firebricks.
If the joints of the brickwork of the air heaters yield in consequence of great
heat (the firebrick of the usual shape do not yield, because on account of their
small dimensions they are well burnt through) and the whole brickwork settles
somewhat in correspondence therewith; this can, under the arrangement herein-
before described, and with the connexion employed only, take place in an even
manner, and then the brickwork will not open, but it will on the contrary become
tighter.
Through the double or more fold raising of the heating chambers n¹ against the
waste-heat flue n leading to the steam boiler or to the chimney a stagnation
of the hot combustible products in the upper part of the chambers a, and
therefore a considerable heating of the side walls, that is to say, of the air is
attained.
The same air-heating apparatus is shown in sketches 2 and 3.
The following is a description of the application of my Invention to glass
furnaces.
All the parts consisting of fireproof material about or in furnaces for making
glass, with which the melting or molten glass metal or the waste flame, which
carries with it amongst other things alkalies, come into contact are attacked, because
the fireproof material, consisting of silica and clay, is dissolved by the glass, which
is not at all charged therewith or by evaporated alkalies.
The attempts to coal the bottoms, bridges, or partitions of furnaces for glass
making purposes, for instance, of continuous tank furnaces by air have naturally
not met with sufficient success. These parts made of double wallings, with water
circulating between them, have not remained tight as taught by experience.
Of the interruption to the working which arise from the repairs of the furnaces,

page_text: the escape of glass and the exchanging of pots, bridges, partitions, through the
impurities which get into the glass by the wearing away of all the fireproof parts,
and which change its quality to such an extent as to render it useless, only a
passing mention is made here.
Hitherto the glass metal about to be melted used to be put sideways into the
pots or tanks, and through the strong draught the lighter particles of the mixture
(glass metal) above all the alkalies are carried away, thus causing the destruction
of all the parts of the furnace, the so called regenerators.
In order to remedy this evil to some extent the glass metal is put in in a damp
state, thereby cooling the pots and furnaces, and thus produces the cracking of the
former.
Hitherto the melting room and the working space with pots, as well as with
tank furnaces, have not been separated, the practice being with the former to cool
the furnace, and consequently also the glass, down to the temperature for working
at which the furnace is kept whilst the work of making the glass is carried on,
and upon beginning the melting it has to be brought again to the temperature
required for it.
With furnaces for manufacturing plate glass the pots containing the molten
glass are singly taken out of the furnace in a very circumstantial manner; they
are then conveyed to the casting table; the contents are poured out under com-
plicated arrangements; the casting is rendered impure through the falling particles
of the pots, and the pots are then put back into the melting furnace.
All these contrivances are not exactly practical, and not suitable for a continuous
working.
If those parts of a furnace for glass-making which have hitherto been made
of some fire proof material, the bottom, sides, and vaults, the partitions or
filtering walls and other parts are replaced by cast iron plates or beams connected
with ea
other and with tubes cast in them, and if water be circulated in them
these parts, plates or beams, thus cooled by water will last extraordinary long,
because they cannot become affected by the inolten glass nor become leaky.
Such parts made in cast iron and cooled by water, as plates or beams, can be
used for,
1st. Glass melting and tap furnaces, that is, such in which the glass is melted
and from which glass can be run into moulds.
2. For glass smelting and working furnace, that is, such in which the glass is
melted and in which it is also worked.
3. For pot and pan furnaces, which may be of intermittent or continuous
working.
If a metal object cooled by water is dipped into molten glass it will become
coated with a layer of glass of a certain thickness, which protects the object cooled
by water from the effect of the heat of the molten glass all the better, since glass
is a very bad conductor of heat.
The thickness of this layer of glass which protects the object cooled by water
depends upon the cross section of the water-ways, the rapidity as well as the
temperature of the water used for cooling it on the one part, and the temperature
of the glass-bath on the other part, and may be regulated by the former agents.
As soon as the small quantity of heat which may be conducted through the
protecting layer of glass, and which is removed through the cooling water, equals
that which is conveyed to the surface of this layer of glass by the fluid glass, the
thickness of the protecting layer of glass remains constant.
The temperature of the glass-bath for the various sorts of glass differs very
little. The quantity, rapidity, and temperature of the cooling water can however
be regulated, and therefore the thickness of the protecting layer of glass can likewise
be regulated.
By employing furnaces cooled by water the melting is consequently effected in a
glass vessel, which cannot be broken and which is indestructible.
This layer of glass does not become very thick, as evidenced by the shape of the

page_text: scorie in blast furnaces, being a calcareous glass difficult of fusion, which after
flowing out remains liquid for a longer time than is desirable for the working.
in
In the opening for the outflow of the scorie, which is only 25 to 35/
diameter, there is generally no scoria deposited at all, whilst the cooling water
does not experience any perceptible rise of the temperature. Such cast iron parts,
plates or beams cooled by water, may however be employed with pot furnaces as
well as with tank furnaces, the latter intermittent or continuous.
If glass of various colors has to be melted simultaneously it will be preferred to
employ a corresponding number of large sections, instead of a tank cooled by
water, over the surface of which (forming the bottom of the furnace), the flame
passes.
The employment of cast iron bridges or partitions, as well as filtering walls
cooled by water, will also be of importance for the more general use of continuous
tank furnaces.
The necessary clarifying of the molten glass before the working place can be
secured with continuous tank furnaces, lasting only by the insertion of bridges or
filtering walls cooled by water, which act upon the principle of pipes communicating
with each other.
If the wallings of the furnace consist of the same material that is to be melted,
that is to say, of pure glass, the quality of the product cannot suffer any more by
the dissolution of the wallings.
On working such furnaces with parts which are cooled by water these are filled
or covered over with a corresponding quantity of the glass metal to be melted,
whereupon the parts cooled by water will, upon the melting of this glass metal, be
coated with the desired layer of pure glass.
The charging of these single divisions for melting in a furnace with one working
side may be effected on the other side.
With a furnace which is worked from two sides the charging is duly arranged
for each division for melting separately, that is to say, from above through the
vaulting.
Tunnels filled with glass metal which is warmed beforehand therein reach up or
into the liquid glass metal, or they form the prolongation of the side walls, by
which means the scattering dust of the glass metal put in, which destroys all the
parts of the furnace, is done away with, for which reason the glass metal need not be
put in in a damp state. The same method of charging may be employed for inter-
mittent or continuous pots, and as such the separate divisions for tanks of a tank
furnace may also be designated.
For the entire working of the furnaces for glass making it is judicious to separate
the space for melting the glass, which must always be kept at melting heat, from
the working room in which it is requisite to have always the most suitable and
lower temperature for manufacturing the glass; it must, however, not be allowed
to become too low, as otherwise the glass might become devitrified or windy.
The
Whilst the glass is worked in the working room melting is again done in the
melting room, thus economising an extraordinary amount of time and fuel.
melting room for glass is provided with one or several tapholes at the sides or at
the bottom, which permit and fully secure the outflow of small or large quantities
of glass into the entirely separated and lower lying room for working the glass
according to desire, or for casting various objects, such as panes, railway sleepers,
and cylinder rests on casting tables in moulds. The hearth of the melting rooms
inclines towards the tapholes, so that the molten glass can run off completely.
If glass of a different colour is to be melted the hearth nearest the taphole is
used first, and then the glass melted after of the previously worked color is
tapped.
With furnaces for making plate glass the melting room for glass is properly
established at such a height that the casting table may be placed under the tap-
holes. With this construction of plate glass furnaces as melting furnaces with
tapholes the casting of panes of any size and thickness, as may be desired, is not

page_text: any more dependent on the size, that is to say, the contents of the separate pots.
The dimensions of the panes are only determined by the size of the casting table
and by the rapidity of the forward movement of the same.
When the casting of a pane is finished the glass tapholes are stopped with blunt
iron rods, the casting table is conveyed in front of the cooling furnace, the pane is
pushed in, the casting table is again placed under the tapholes, the blunt rod in
the same is put into the liquid glass, the rods are then quickly withdrawn and
another pane is cast from the glass that flows out.
The glass taphole may also be stopped with clay or sand provided the use of
such materials has not to be excluded on account of the casting coming impure
thereby. By the described arrangement of the plate glass furnaces all the pots are
saved, no glass is lost, all the extraordinary difficulties of casting and the many
doors of the plate glass furnace used hitherto are avoided.
In the place of the casting table chills or moulds for objects of every kind may
be placed under the tapholes, and the same process on casting them, as above
described, may be carried out.
Since the taphole can be manipulated with ease one may often, ad libitum, make
small trials of castings before making the definite castings, the quality and purity
of the glass thus obtained may thus be examined, and any requisite modifications
may be effected by corresponding additions. If necessary the glass tapholes, like
other parts of the furnace, are cooled by water, and such a cooled glass taphole may
consist of cast iron with wrought iron tubes cast in it, or of hollow bronze or copper
casting. The cooling of glass melting rooms described is all the easier, since, for
instance, the present enormously large plate glass furnaces may be transformed
through the described doing away of the pots, and with the same capacity of holding
the liquid glass into proportionately small melting rooms.
On page I., Figures 3, 8, inclusive, a glass melting and tap furnace A is shown,
the whole melting room of which consists of plates b cooled with water; this furnace
can be used in the manufacture of plate or any other glass.
The furnace being supported by the X irons B, and resting on the pillars e,
which are covered by cast iron plates d, is elevated high enough above the ground
level y that the moulds can be placed or passed below the taphole.
The arrangement of casting when the water cooled taphole a, Figures I. and II.,
is used has already been described.
The slits c in the cooled side plates b, in which the taphole a is fixed, page I.,
Figures 3, 4, and 7, are lengthways in order to be able to arrange the taphole
higher or lower.
The bottom of the glass smelting and tap furnace, page I., Figures 3 and 4, is
also constructed of water cooled plates b, and is inclined towards that side in which
the glass tap a is arranged.
The glass taps shown in page I., Figures 1 and 2, have a circular opening, and
in Figure 2 an oblong opening, which can be closed with an iron bar of corresponding
shape.
The exterior shape of the glass taps, as also the shape of the glass exit, is of any
convenient shape.
On page I. the parts not before mentioned of the furnace are shown; g', gå, gas
flues, that is, gas exit; o, o', 0%, air shaft, air flue, air exits; n, n¹, n², bridge
opening, waste heat shafts, waste heat flue; f, f, openings for cleaning the shafts,
flues, and for reducing or changing the section over fire bridge by filling with fire
bricks.
In observation, working, and introducing opening for all kinds of smelting
furnaces it is of importance to have a space above the melted material filled with
stagnant heat, from which the heat reflects upon the hearth of the furnace, that is,
upon the material to be heated.
For this purpose the vault in Figure 3, page I., is arranged lower at the fire
bridge, and thus a larger storing place created in which the heat stagnates,

page_text: This arrangement has not been tried hitherto, or could not be utilized, as the
vault would have melted, horizontal vaults have therefore been used.
By using the bent piece p cooled with water, one is able to use a vault of desired
height above the hearth of the furnace.
On page 2, Figures 1-3, a glass and tap furnace is shown, from which the glass
may be used direct.
As heavy glass pieces will settle down on the bottom of these glass and working
ovens which are hardly ever entirely emptied, and the bottom of such furnaces then
suffer much less than those exposed directly to the flame, the bottom of the glass
melting furnace can be made of fire bricks, as shewn in page 2.
As however fire bricks of large size are not equally burnt and contain cracks,
small firebricks of ordinary size which do not contain these defects were used, but
were subject on account of the specific gravity of 1.85 to get loose, and float on the
top of the melted glass of 2.46 to 3.33 specific gravity.
These defects are obviated by forming the hearth or bottom of the furnace of one
or several layers of bricks, formed of bricks of the shape, as shewn in page 2,
Figures 1 and 2, jointed in such a way that the weight of the side walls inclusive
of vault of the furnace keeps the same down.
By this construction the bottom of the furnace cannot be pushed upwards, and
will last considerably longer.
Some examples of the shape of these bricks for forming the hearth or bottom are
shewn on page 2, Figure 3, c, d, e.
On page
the various parts of furnace are shown as follows:-g, g', g², gas flue,
gas shaft, that is, gas exit; o, o¹, 0%, air shafts, air flues, that is, air exit; n, n¹,
fire bridge opening, waste heat shafts; f. f. f, opening partly for cleaning the
shafts, flues, partly for reducing the section over fire bridge by introducing fire
bricks.
In 15, working openings; b, two side openings for introducing the glass material
or working w bottom cooling canal.
Having thus described and ascertained the nature of the said Invention, and
manner in which it is to be performed, I would observe in conclusion that what I
consider novel and original, and therefore claim as constituting the Invention
secured to me by the said hereinbefore in part recited Letters Patent are,-
1. Gas expelling chambers made of firebricks of the usual size and shape, which,
as drawn in sketch 1, are so arranged that the thicknesses of the bottoms and sides
of the gas expelling chambers may be equal to the smallest dimensions of these
bricks, substantially as hereinbefore described.
2. A trellis brick work which supports, as drawn in sketch 1, the borders of the
gas expelling chambers which tightens the cross joints of the brickwork of the
same, forms the flues for the waste heat, and which is made from firebricks of
the usual shape, arranged in such manner that the supports of the walls of the gas
expelling chambers may be equal to the smallest dimensions of these bricks,
substantially as hereinbefore described.
3. The arrangement of the flues and combustion chambers as drawn, which
permits that the gas completely, as well as partially or not at all, passes either into
the place where the heat is used (the furnace), or under the gas expelling chambers
of the generators, or to the steam boilers, if any, and that it burns with the air
admitted, substantially as herein before described.
4. The application of sliding registers cooled by water in frames, sketches 2
and 3, marked h, h¹, h³, and h³, for the regulation and the complete shutting off of
gases in furnaces, generators, and steam boilers, substantially as herein before
described.
5. The slits b for air and slag slanting from two sides towards the middle without
any auxiliary grate of any kind for fire arrangements and generators, substantially
as herein before described.
6. The maintenance of the dimensions of these slits by the application of cast

page_text: iron beams L cooled by water with respect to their extent, substantially as herein-
before described.
7. The establishment of arrangements for shutting off the air in fire places and
generators of every kind by the frame M with a swallow tail shaped gutter, of a
rib corresponding to it, of a moveable door N, of tightening through clay or loan,
of fastening through the iron O and a wedge, substantially as herein before
described.
8. The application of beams Co cooled by water, sketches 4 to 14, in replacement
of parts which were hitherto made of firebricks for fireplaces of every kind, and for
generators, and for the maintenance of such parts which are also further made from
firebricks, substantially as hereinbefore described.
9. The employment of perpendicular air heating shafts O¹, 3 and 4, in the
separating walls of the heating chamber of the size of a three quarter piece of the
shape of brick employed, or of a multiple of such a three quarter piece, and the
connection thereby rendered possible as drawn in sketches 18 and 19, that is to
say,
the exclusive employment of entire bricks of the usual shape for the construction
of the separating walls concerned, substantially as herein before described.
10. The employment of a filling in between the air heater and the outer walls
of the same in order to permit of the even settlement of the air heater, substantially
as hereinbefore described.
11. A single or repeated raising of the heating chambers n' in the air heating
apparatuses against the heating flue n², by which a stagnation of the hot combustible
products in the chambers n', and thereby a better heating of the air is produced,
substantially as hereinbefore described.
12. The employment of cast iron pieces, plates, beams, and other contrivances
with cast iron tubes cast in them for the cooling by water, for the formation of
side wallings, bottoms, vaultings, bridges, separating or filtering walls, and other
parts in furnaces for making glass by intermittent or continuous working, also in
pots and tank furnaces, substantially as hereinbefore described and set forth.
13. The method of charging pots, divisions of tanks, or tanks with glass metal
that is to be melted intermittently or continuously, by funnels from above which
reached up into the molten glass metal, or which join the side wallings of the glass
pots or the divisions of the tanks, substantially as hereinbefore described.
14. The employment of separate rooms for melting and for the manufacture of
glass, substantially as hereinbefore described.
15. The arrangements of the melting room for glass with respect to the direct
tapping as well as the matter and method to tap any desired quantities of molten
glass into the working room for glass, into the casting table, or into moulds for
castings, substantially as hereinbefore described.
16. The making and employment of glass tapholes cooled by water, with pot or
tank furnaces, or with rooms for melting glass or for making glass, substantially
as hereinbefore described.
17. The arrangement of gas flue g, the gas shafts g, and the gas exits g², between
the generator or firing arrangement and glass furnace, as shown on page 1 and 2,
further the air shafts o, o¹, the air flues o¹, and an air exit o², between the air heater
and glass furnace, in which arrangement the air exit o² is above the gas exit g²,
substantially as hereinbefore described.
18. The arrangement, as shown on page 1 and 2, of waste heat exit n, the waste
heat shafts n³, the waste heat flues (page 1) between the air heater, generator, and
steam boiler, as also the opening f for altering the section of the air, gas, and waste
heat exits o², g², n', substantially as herein before described.
19. The arrangement, shown on page 2, of waste heat opening n and the waste
heat shafts n¹ on both sides of the furnace in order that the heating gases produced
before g² in the middle of the furnace must follow the outer walls of the furnace,
and thereby keeping the melted glass as hot as in the middle, substantially as
herein before described,

page_text: 20. The arrangement of working openings k on the long sides and small sides
of the furnace between the waste heat openings n, page 2, substantially as
herein before described.
21. The combination and arrangement of the distilling or sublimating chambers
(which are continuously charged by any suitable mechanical mechanism, and which
are arranged in connecting with the heating flues) with the evacuating chamber,
substantially as and for the purposes herein before described and set forth.
In witness whereof, I, the said George Alexander Dick, have hereunto set
my hand and seal, this Nineteenth day of April, in the year of our Lord
One thousand eight hundred and eighty one.
G. ALEXANDER DICK. (L.S.)