IMPROVEMENTS IN APPARATUS FOR HEATING SOLID SUBSTANCES OUT OF CONTACT WITH THE PRODUCTS OF THE COMBUSTION OF THE FUEL EMPLOYED
Year: 1885

page_text: I, WALTER WELDON, of Rede Hall, Burstow, in the County of Surrey, Fellow
of the Royal Society, do hereby declare the nature of the said Invention for
IMPROVEMENTS IN APPARATUS FOR HEATING SOLID SUBSTANCES OUT OF CONTACT
WITH THE PRODUCTS OF THE COMBUSTION OF THE FUEL EMPLOYED, to be as
follows:-
The patent N° 9304, of the 23rd June, 1884, is for a method of heating solid
substances out of contact with the products of combustion of the fuel employed.
The principle of that method is described in the specification of the aforesaid
patent as follows: "By this invention, masses of brickwork, or other suitable
material, so arranged and disposed as to form convenient receptacles for the
solid substance or substances to be heated, are first raised to a sufficient temperature
by being brought into contact with products of combustion or other hot gases,
which products of combustion or other hot gases pass into and through the said
receptacles, and when the said masses of brickwork have been thus raised to a
sufficient temperature, and a sufficient quantity of heat has so been stored up in
them, the admission into the said receptacles of products of combustion or other
hot gases is suspended, and there is charged into the said receptacles the solid
substance or substances to which it is desired to apply heat, and which then
become raised to the requisite temperature by absorption of some of the heat so
stored up in the said masses of brickwork or other material. When the said solid
substance or substances have been sufficiently heated in this way, they, or the
residual products of heating them, as the case may be, are discharged from the said
receptacles, which receptacles are then again heated as before, and so rendered
capable of raising to the requisite temperature another charge of the solid substance
or substances to be treated." The specification of the said patent then described
a particular apparatus for carrying the said invention into effect. Experience
has now shown that, in certain special cases, the apparatus so described. presents

page_text: certain inconveniences. The present invention consists in a new and special form
of apparatus, by which the said inconveniences are avoided.
The apparatus which constitutes the present invention differs from the particular
form of apparatus described in the specification of patent No 9304 of 1884,
especially in two particulars. Alike in the said former apparatus and in the
apparatus which constitutes the present invention, the furnace proper consists of
a series of working chambers, but whereas in the said former apparatus the said
working chambers are so arranged and disposed that the products of combustion
employed to heat them traverse successively every chamber of the series, either
entering at the top of the first chamber, passing from the bottom of the first
chamber into the lower part of the second chamber, then passing from the top of
the second chamber into the upper part of the third chamber, and so on, or
entering at the bottom of the first chamber, passing from the top of the first
chamber into the upper part of the second chamber, then passing from the bottom
of the second chamber into the lower part of the third chamber, and so on
successively, in the apparatus which constitutes the present invention the products
of combustion employed to heat its working chambers do not pass from one of
those chambers to another of them, entering one of them by its lower or upper
extremity, and the next by its upper or lower extremity, and so on successively,
but all the working chambers communicate, by the same extremity of each of them,
with a common combustion chamber, and products of combustion enter each of
the working chambers directly from the combustion chamber, entering all the
working chambers either at the upper extremity of each of them or at the lower
extremity of each of them, and the products of combustion which have traversed
one working chamber not passing on to another working chamber, but. passing
directly from the one working chamber which they have traversed into other
apparatus, as will be hereinafter explained. Secondly, whereas the said former
apparatus included two fixed regenerators, in the apparatus which constitutes the
present invention there is substituted for those two fixed regenerators a movable
burner, which is preferably, though not necessarily, a regenerator also.
The accompanying three sheets of drawings represent the apparatus which
constitutes the present invention, when that apparatus is so disposed that the
products of combustion employed to heat its working chambers enter those
chambers at the upper extremity of each of them. They show an apparatus
having four working chambers. It will be well understood, however, that the
number of working chambers per apparatus may be more or less than four, and
also that the products of combustion employed to heat its working chambers may
euter each of those chambers at its lower extremity, instead of at its upper
extremity, as in the apparatus shown in the drawings.
While applicable to many other purposes also, the apparatus which constitutes
the present invention is especially useful for decomposing solid chemical compounds
by heating them in a current either of air, or of auy gas or gases, or of steam or
other vapour, or of any mixture of a gas or gases with a vapour or vapours. In
the following description, it will be supposed that the apparatus is employed for
heating magnesium oxychloride in a current of air.
The apparatus is illustrated by the accompanying drawings.
Figure 1 shows a vertical section, alike of the furnace proper and of the movable
regenerative burner.
Figure 2 shows a horizontal section, alike of the furnace proper and of the said
movable regenerative burner. The upper part of this section is taken along the
line C, D, Figure 1, and the lower part of it along the line E, F, Figure 1.
Alike in Figure 1 and in Figure 2, the movable regenerative burner is shown
in the position, in relation to the furnace proper, which it occupies during the
operation of heating up the working chainbers of the latter.
Figure 3 shows a vertical section of the furnace proper, taken at right angles to
the section shown in Figure 1.
U

page_text: Figure 5 is a vertical section of the furnace proper, after its working chambers
have been heated up, the movable regenerative burner removed, and the working
chambers of the furnace proper charged with the solid material which is to be
treated in them.
Figure 6 is a horizontal section, taken along the line I, J, Figure 5.
Figure 7 is a vertical section of the movable regenerative burner, taken along
the broken line K, L, Figure 1.
The same letters refer to the same parts of the apparatus in all the Figures.
In the following description, it will be supposed that the chlorine-yielding body
which is heated in a current of air is oxychloride of magnesium.
A, A, A, A, are four narrow working chambers, having very thick walls. The
upper extremity of each chamber, A, opens into the combustion chamber, B.
The lower extremity of each chamber, A, communicates with one of the four
horizontal channels, a, a, a, a.
D, Figures 1 and 7, is the movable regenerative burner. It consists of a system
of cast-iron pipes, contained in an envelope of masonry, which envelope of masonry
is encased with iron plates, and securely armatured. The cast-iron pipes are of
rectangular section, and each of them is divided, by two vertical partitions, into
three compartments, i, o, u. The central compartments, o, o, o, etc., convey gaseous
fuel into the combustion chamber, B, and the side compartments, and u, convey
air into the combustion chamber. The gaseous fuel is supplied by the main pipe
upon which is the valve, N, Figure 2, from which main pipe it passes, by the
pipes, V, and C, Figure 2, into the flue, C, Figures 1 and 7, from which flue C it
enters the compartments, o, o, o, by apertures at the bottom of those compartments.
Having reached the upper extremity of the compartments, o, o, o, the gaseous fuel
issues into the combustion chamber, B, by the small pipes, d, d, d, Figures 1, 2,
and 7. The air which is to burn the gaseous fuel enters at the bottom of the
compartments, i and u, and, having risen to the upper extremity of those
compartments, issues into the combustion chamber by the wide flat pipe, T,
Figure 1. It will be seen from Figures 1 and 7 that the small pipes, d, d, d, pass
through this wide flat pipe, T, and that the small pipes, d, d, d, are a little longer
than the flat pipe, T.
The pipe, V, Figure 2, is fixed to the main pipe on which is the valve, N. The
pipe, C, Figure 2, is fixed to the movable regenerative burner. When the movable
regenerative burner is in the position, in relation to the furnace proper, in which it
is shown in Figures 1 and 2, the pipe C communicates with the pipe V, at the
point U, Figure 1. The joint at U is one which can be readily made and readily
unmade.
From the combustion chamber, B, products of combustion enter the narrow
working chambers, A, A, A, A, by the upper extremity of each of them. After
traversing these chambers downwards, they pass off, by the four horizontal
channels, a, a, a, a, into the movable regenerative burner. Following the direction
of the arrows in Figure 1, they first pass upwards through the flues, Z, Z, Z,
Figures 1 and 2, and then travel downwards, circulating round the rectangular
cast-iron vertical pipes which have been described, and passing between those
rectangular pipes, and then passing off from the burner by the pipe, P, Figures 1
and 2, which conveys them to the flue, G, Figure 1. In thus passing downwards
through the movable burner, they heat the gaseous fuel which is passing upwards
through the compartments, o, and the air which is passing upwards through the
compartments, i and u.
The pipe, P, which is fixed, communicates with the flue by which products of
combustion pass off from the movable burner by the piece, Q, the lower part of
which fits into the upper part of the pipe, P, in such manner that the piece, Q, can
be raised or lowered by the lever, S.
It will be seen from Figures 1 and 6 that the whole regenerative burner is
mounted on wheels. When the burner is in the position, in relation to the fur-
nace proper, in which it is shown in Figures 1 and 2, the wheels of the. movable

page_text: regenerative burner stand on rails upon a truck, K, K, Figures 1, 2, and 7. This
truck also stands on rails. When the truck is drawn a short distance from the
furnace proper, the rails on the truck K become in such a position in relation to
other rails, one of which is shown at r, Figure 1, that the burner can be transferred
to those other rails, and drawn along them on to another truck, installed opposite
another furnace. Thus, while oxychloride of magnesium is being heated in a
current of air in one furnace, the movable regenerative burner can be employed to
heat up the working chambers of another similar furnace.
The working of the apparatus will now be easily understood.
When the four working chambers, A, A, A, A, have been heated to a sufficient
temperature, the first step is to close the valve, N, Figures 2 and 3, and so to cut
off the supply of combustible gas to the movable regenerative burner. The pipe, C,
Figures 1 and 2, must then be disconnected from the pipe, V, Figure 2, the pipe, P,
must be lowered, and then the truck on which the whole regenerative burner is
supported must be drawn away from the furnace proper, until the wheels of the
burner are opposite the rails, one of which is marked, ", in Figure 1. The
openings by which products. of combustion have entered the working chambers
must now be closed by the door, E, E, Figures 1 and 5, and the opening by which
those products of combustion have passed off from the working chambers must be
closed by the doors, F, F, F, Figures 1, 5, and 6. One door, E, and one door, F,
suffice for the whole furnace: as will be seen, as regards the door F, from Figure 6.
The doors E and F are hung on hinges, as will be understood from Figure 1; and
when they are in position to close the openings to which they correspond, they are
pressed tightly against their seats by screws, as shown in Figures 5 and 6. The
working chambers, A, A, A, A, have now to be charged with oxychloride of
magnesium, in small pieces, from a tip-wagon charged therewith which has been
previously brought into position on the top of the furnace. The oxychloride enters
the working chambers by the opening H, H, H, Figures 1, 3, and 5. The cover or
door which closes this opening is seen in Figures 1, 3, and 5, but is not marked with
any letter. This cover having been removed, a hopper is brought over the
opening, H, and oxychloride is then poured into the hopper, whence it falls into
the working chambers, A, A, A, A. The door or cover of the opening, H, is then
rapidly replaced, and air is then admitted into A, A, A, A, through apertures in the
door E, which apertures are not shown in the drawings. The oxychloride rapidly
becomes heated, by absorption of some of the heat previously stored up in the walls
of the chambers in which it is contained, and there passes off from those chambers
a mixture of gases and vapours containing both free chlorine and vapour of
hydrochloric acid. This mixture of gases and vapours passes off from A, A, A, A,
by the horizontal channels, a, a, a, a, into the vacant space between the masonry
of the furnace and the door, F, which vacant space is seen in Figure 6, and then
passes, by the channel, Z, Figures 2, 4, and 6, into the pipe, m, Figures 2, 3, 4, and G.
From the pipe, m, the said inixture of gases and vapours is conveyed to apparatus
for condensing out of it its vapour of hydrochloric acid, and what passes off from
that apparatus then goes on to apparatus for the absorption of its chlorine. The
air which enters the chambers, A, A, A, A, through apertures in the door, E, may
either be forced in under pressure, or be drawn in by means of an aspirator. It is
preferable that it should be drawn in by means of an aspirator, and that this
aspirator should be placed after the chlorine absorption apparatus.
When the decomposition of the oxychloride has proceeded sufficiently far, the
admission of air into the working chainbers must be arrested, the door F must be
opened, and the residual oxide contained in the chambers, A, A, A, A, must then be
discharged. That residual oxide is drawn out of the horizontal channels, a, a, a, a,
by means of a suitable rake. If need be, to facilitate the descent of the said
residual oxide to the bottom of each chamber, A, A, A, A, a tool may be introduced
into the upper extremities of those chambers by the opening H. When the
residual oxide has been completely discharged, the cover of the opening H must be
replaced, and then, the door E having been opened, the movable regenerative burner

page_text: must be brought back into the position in which it is shown in Figure 1, and the
working chambers of the furnace proper must then be heated up again for another
operation.
When the apparatus is employed, not for heating oxychloride of magnesium in a
current of air, or for heating the material treated, whatever be that material, in a
current of gas or vapour, and when the material treated does not itself give off gas
or vapour during the operation of heating it, neither holes in the door E, nor the
channel, l, nor the pipe, m, will be required.
Each working chamber may be provided with a sight-hole capable of being
opened and closed at will, through which the temperature of the contents of the
narrow working chambers may be observed. Such a sight-hole is shown at y,
Figure 1.
The details of the apparatus thus described may be varied in many ways. For
example, without departing from the principle of the apparatus above described,
the number of working chambers in that part of the apparatus which constitutes
the furnace proper may be greater or less than four; that part of the apparatus
may be so disposed that the products of combustion entering the working chambers
may pass in at their lower extremities and pass out at their upper extremities, the
current of air, or gas or vapour which afterwards enters them during the same;
and the mode of charging the working chambers, the method of discharging those
chambers, the method of closing the various openings in the furnace, and the mode
of constructing and working the movable regenerative, burner, may all be varied
from those above described. Moreover, the movable burner need not necessarily
be a regenerator also, though it will usually be preferable that it should be so.
What is new in the present invention consists in:
"
An apparatus for heating solid bodies, or any mixture of two or more solid
bodies, out of contact with the pro lucts of combustion of the fuel employed, the
said solid bodies being either heated by themselves, or in a current either of air, or
of any gas or mixture of gases, or of any vapour or mixture of vapours, or of any
mixture of a gas or gases with a vapour or vapours, that part of the apparatus
which constitutes the furnace proper consisting of one or more narrow working
chambers, having thick walls, and being heated by the passage through them of
products of combustion, before they are charged with the solid substance or mixture
of substances which is to be heated in them, the entrance into the said narrow
working chambers of the said products of combustion being arrested before the
said solid substance or mixture of solid substances is charged into the said narrow
working chambers, and that solid material or mixture of solid materials being then
heated by absorption of some of the heat previously stored up in the said walls of
the said narrow working chambers, the said chambers, (when the apparatus
contains more than one of them), not communicating one with another, but all
communicating with a common combustion chamber, from which products of
combustion enter them all by the same extremity of each of them, the products of
combustion which have traversed one of the said narrow working chambers not
then traversing any of the other chambers of the series, but passing off from the
one chamber which they have traversed into other apparatus; the combination
with-such narrow working chambers of a movable burner, for heating those narrow
chambers by the products of the combustion of gaseous fuel; and heating that
gaseous fuel, and the air which is to burn it, in the movable burner itself, by the
products of combustion which have traversed and passed off from the narrow
working chambers of that part of the apparatus constituting the furnace proper.

page_text: Improvements in Apparatus for Heating Solid Substances out of
Contact with the Products of the Combustion of the Fuel
Employed.
I, WALTER FRANK RAPHAEL WELDON, of No 19 Great George Street, West-
minster, in the County of Middlesex, Administrator of the late Walter Weldon,
the Applicant, 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:-
The patent No 9304, of the 23rd June 1884, is for a method of heating solid
substances out of contact with the products of combustion of the fuel employed.
The principle of that method is described in the specification of the aforesaid
patent as follows: "By this invention, masses of brickwork, or other suitable
material, so arranged and disposed as to form convenient receptacles for the solid
substance or substances to be heated, are first raised to a sufficient temperature by
being brought into contact with products of combustion or other hot gases, which
products of combustion or other hot gases pass into and through the said receptacles,
and when the said masses of brickwork have been thus raised to a sufficient
temperature, and a sufficient quantity of heat has so been stored up in them, the
admission into the said receptacles of products of combustion or other hot gases is
suspended, and there is charged into the said receptacles the solid substance or
substances to which it is desired to apply heat, and which then become raised to
the requisite temperature by absorption of some of the heat so stored up in the
said masses of brickwork or other material. When the said solid substance or
substances have been sufficiently heated in this way, they, or the residual products
of heating them, as the case may be, are discharged from the said receptacles,
which receptacles are then again heated as before, and so rendered capable of
raising to the requisite temperature another charge of the solid substance or
substances to be treated." The specification of the said patent then described
a particular apparatus for carrying the said invention into effect. Experience has
now shown that, in certain special cases, the apparatus so described presents
certain inconveniences. The present invention consists in a new and special form
of apparatus, by which the said inconveniences are avoided.
The apparatus which constitutes the present invention differs from the particular
form of apparatus described in the specification of patent No 9304 of 1884,
especially in two particulars. Alike in the said former apparatus and in the.
apparatus which constitutes the present invention, the furnace proper consists of
a series of working chambers; but whereas in the said former apparatus the said
working chambers are so arranged and disposed that the products of combustion
employed to heat them traverse successively every chamber of the series, either
entering at the top of the first chamber, passing from the bottom of the first
chamber into the lower part of the second chamber, then passing from the top
of the second chamber into the upper part of the third chamber, and so on, or

page_text: entering at the bottom of the first chamber, passing from the top of the first
chamber into the upper part of the second chamber, then passing from the bottom
of the second chamber into the lower part of the third chamber, and so on
successively, in the apparatus which constitutes the present invention the products
of combustion employed to heat its working chambers do not pass from one of
those chambers to another of them, entering one of them by its lower or upper
extremity, and the next by its upper or lower extremity, and so on successively,
but all the working chambers communicate, by the same extremity of each of
them, with a common combustion chamber, and products of combustion enter each
of the working chambers directly from the combustion chamber, entering all the
working chambers either at the upper extremity of each of them or at the lower
extremity of each of them, and the products of combustion which have traversed
one working chamber not passing on to another working chamber, but passing
directly from the one working chamber which they have traversed into other
apparatus, as will be hereinafter explained. Secondly, whereas the said former
apparatus included two fixed regenerators, in the apparatus which constitutes the
present invention there is substituted for those two fixed regenerators a movable
burner, which is preferably, though not necessarily, a regenerator also.
The accompanying three sheets of drawings represent the apparatus which
constitutes the present invention, when that apparatus is so disposed that the
products of combustion employed to heat its working chambers enter those
chambers at the upper extremity of each of them. They show an apparatus
having four working chambers. It will be well understood, however, that the
number of working chambers per apparatus may be more or less than four, and
also that the products of combustion employed to heat its working chambers may
enter each of those chambers at its lower extremity, instead of at its upper
extremity, as in the apparatus shown in the drawings.
While applicable to many other purposes also, the apparatus which constitutes
the present invention is especially useful for decomposing solid chemical compounds
by heating them in a current either of air, or of any gas or gases, or of steam or
other vapour, or of any mixture of a gas or gases with a vapour or vapours. In
the following description it will be supposed that the apparatus is employed for
heating magnesium oxychloride in a current of air.
The apparatus is illustrated by the accompanying drawings.
Figure 1 shows a vertical section, alike of the furnace proper and of the movable
regenerative burner.
Figure 2 shows a horizontal section, alike of the furnace proper and of the said
movable regenerative burner. The upper part of this section is taken along the
line C, D, Figure 1, and the lower part of it along the line E, F, Figure 1.
Alike in Figure 1 and in Figure 2, the movable regenerative burner is shown
in the position, in relation to the furnace proper, which it occupies during the
operation of heating up the working chambers of the latter.
Figure 3 shows a vertical section of the furnace proper, taken at right angles to
the section shown in Figure 1.
Figure 4 is a horizontal section along the line G, H, Figure 3.
Figure 5 is a vertical section of the furnace proper, after its working chambers
have been heated up, the movable regenerative burner removed, and the working
chambers of the furnace proper charged with the solid material which is to be
treated in them.
Figure 6 is a horizontal section, taken along the line I, J, Figure 5.
Figure 7 is a vertical section of the movable regenerative burner, taken along
the broken line K, L, Figure 1.
The same letters refer to the same parts of the apparatus in all the Figures.
In the following description, it will be supposed that the chlorine-yielding body
which is heated in a current of air is oxychloride of magnesium.
A, A, A, A, are four narrow working chambers, having very thick walls. The
upper extremity, of each chamber. A opens into the combustion chamber, B.
.

page_text: The lower extremity of each chamber A communicates with one of the four
horizontal channels, a, a, a, a.
D, Figures 1 and 7, is the movable regenerative burner. It consists of a system
of cast iron pipes, contained in an envelope of masonry, which envelope of masonry
is encased with iron plates, and securely armatured. The cast iron pipes are of
rectangular section, and each of them is divided, by two vertical partitions, into
three compartments, i, o, u. The central compartments, o, o, o, etc., convey gaseous
fuel into the combustion chamber B, and the side compartments i and u, convey
air into the combustion chamber. The gaseous fuel is supplied by the main pipe
upon which is the valve N, Figure 2, from which main pipe it passes, by the
pipes V and C, Figure 2, into the flue C, Figures 1 and 7, from which flue C it
enters the compartments o, o, o, by apertures at the bottom of those compartments.
Having reached the upper extremity of the compartments o, o, o, the gaseous fuel
issues into the combustion chamber B, by the small pipes d, d, d, Figures 1, 2,
and 7. The air which is to burn the gaseous fuel enters at the bottom of the
compartments i and u, and, having risen to the upper extremity of those compart-
ments, issues into the combustion chamber by the wide flat pipe T, Figure 1. It
will be seen from Figures 1 and 7 that the small pipes d, d, d, pass through this
wide flat pipe T, and that the small pipes d, d, d, are a little longer than the flat
pipe T.
The pipe V, Figure 2, is fixed to the main pipe on which is the valve N. The
pipe C, Figure 2, is fixed to the movable regenerative burner. When the movable
regenerative burner is in the position, in relation to the furnace proper, in which it
is shown in Figures 1 and 2, the pipe C communicates with the pipe V, at the
point U, Figure 1. The joint at U is one which can be readily made and readily
unmade.
From the combustion chamber B, products of combustion enter the narrow
working chambers A, A, A, A, by the upper extremity of each of them. After
traversing these chambers downwards, they pass off, by the four horizontal
channels a, a, a, a, into the movable regenerative burner. Following the direction
of the arrows in Figure 1, they first pass upwards through the flues Z, Z, Z,
Figures 1 and 2, and then travel downwards, circulating round the rectangular
cast-iron vertical pipes which have been described, and passing between those
rectangular pipes, and then passing off from the burner by the pipe P, Figures 1
and 2, which conveys them to the flue G, Figure 1. In thus passing downwards
through the movable burner, they heat the gaseous fuel which is passing upwards
through the compartments o, and the air which is passing upwards through the
compartments i and u.
The pipe P, which is fixed, communicates with the flue by which products of
combustion pass off from the movable burner by the piece Q, the lower part of
which fits into the upper part of the pipe P, in such manner that the piece Q can
be raised or lowered by the lever S.
It will be seen from Figures 1 and 7 that the whole regenerative burner is
mounted on wheels. When the burner is in the position, in relation to the furnace
proper, in which it is shown in Figures 1 and 2, the wheels of the movable
regenerative burner stand on rails upon a truck K, K, Figures 1, 2, and 7. This
truck also stands on rails. When the truck is drawn a short distance from the
furnace proper, the rails on the truck K become in such a position in relation to
other rails, one of which is shown at r, Figure 1, that the burner can be transferred
to those other rails, and drawn along them on to another truck installed opposite
another furnace. Thus, while oxychloride of magnesium is being heated in a
current of air in one furnace, the movable regenerative burner can be employed
to heat up the working chambers of another similar furnace.
The working of the apparatus will now be easily understood.
When the four working chambers A, A, A, A, have been heated to a sufficient !
temperature, the first step is to close the valve N, Figures 2 and 3, and so to cut
off the supply of combustible gas to the movable regenerative burner. The pipe C,

page_text: Figures 1 and 2, must then be disconnected from the pipe V, Figure 2, the pipe P
must be lowered, and then the truck on which the whole regenerative burner is
supported must be drawn away from the furnace proper, until the wheels of the
burner are opposite the rails, one of which is marked, r, in Figure 1. The openings
by which products of combustion have entered the working chambers must now be
closed by the door E, E, Figures 1 and 5, and the opening by which those products
of combustion have passed off from the working chambers must be closed by the
doors, F, F, F, Figures 1, 5, and 6. One door E, and one door F, suffice for the
whole furnace: as will be seen, as regards the door F, from Figure 6. The doors E
and F are hung on hinges, as will be understood from Figure 1; and when they
are in position to close the openings to which they correspond, they are pressed
tightly against their seats by screws, as shown in Figures 5 and 6. The working
chambers A, A, A, A, have now to be charged with oxychloride of magnesium, in
small pieces, from a tip-wagon charged therewith which has been previously brought
into position on the top of the furnace. The oxychloride enters the working
chambers by the opening H, H, H, Figures 1, 3, and 5. The cover or door which
closes this opening is seen in Figures 1, 3, and 5, but is not marked with any
letter. This cover having been removed, a hopper is brought over the opening H,
and oxychloride is then poured into the hopper, whence it falls into the working
chambers A, A, A, A. The door or cover of the opening H is then rapidly replaced,
and air is then admitted into A, A, A, A, through apertures in the door E, which
apertures are not shown in the drawings. The oxychloride rapidly becomes heated,
by absorption of some of the heat previously stored up in the walls of the chambers
in which it is contained, and there passes off from those chambers a mixture of
gases and vapours containing both free chlorine and vapour of hydrochloric acid.
This mixture of gases and vapours passes off from A, A, A, A, by the horizontal
channels a, a, a, a, into the vacant space between the masonry of the furnace and
the door F, which vacant space is seen in Figure 6, and then passes by the
channel L, Figures 2, 4, and 6, into the pipe m, Figures 2, 3, 4, and 6. From the
pipe m, the said mixture of gases and vapours is conveyed to apparatu+ for
condensing out of it its vapour of hydrochloric acid, and what passes off from that
apparatus then goes on to apparatus for the absorption of its chlorine. The air
which enters the chambers A, A, A, A, through apertures in the door E, may either
be forced in under pressure, or be drawn in by means of an aspirator. It is
preferable that it should be drawn in by means of an aspirator, and that this
aspirator should be placed after the chlorine absorption apparatus.
When the decomposition of the oxychloride has proceeded sufficiently far, the
admission of air into the working chambers must be arrested, the door I must be
opened, and the residual oxide contained in the chambers, A, A, A, A, must then
be discharged. That residual oxide is drawn out of the horizontal channels a, a,
a, a, by means of a suitable rake. If need be, to facilitate the descent of the said
residual oxide to the bottom of each chamber A, A, A, A, a tool may be introduced
into the upper extremities of those chambers by the opening H. When the
residual oxide has been completely discharged, the cover of the opening H must be
replaced, and then, the door E having been opened, the movable regenerative burner
must be brought back into the position in which it is shown in Figure 1, and
the working chambers of the furnace proper must then be heated up again for
another operation.
When the apparatus is employed, not for heating oxychloride of magnesium in
a current of air, or for heating the material treated, whatever be that material, in
a current of gas or vapour, and when the material treated does not itself give off
gas or vapour during the operation of heating it, neither holes in the door E, nor
the channel l, nor the pipe m will be required.
Each working chamber may be provided with a sight-hole capable of being
opened and closed at will, through which the temperature of the contents of
the narrow working chambers may be observed. Such a sight-hole is shown at y,
Figure 1.

page_text: The details of the apparatus thus described may be varied in many ways. For
example, without departing from the principle of the apparatus above described,
the number of working chambers in that part of the apparatus which constitutes
the furnace proper may be greater or less than four; that part of the apparatus
may be so disposed that the products of combustion entering the working chambers
may pass in at their lower extremities and pass out at their upper extremities, the
current of air, or gas, or vapour which afterwards enters them doing the same; and
the mode of charging the working chambers, the method of discharging those
chambers, the method of closing the various openings in the furnace, and the mode
of constructing and working the movable regenerative burner, may all be varied
from those above described. Moreover the movable burner need not necessarily be
a regenerator also, though it will usually be preferable that it should be so.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, I declare that what
I claim is :-
The herein described apparatus for heating solid bodies, or any mixture of two
or more solid bodies, out of contact with the products of combustion of the fuel
employed, the said solid bodies being either heated by themselves, or in a current
either of air, or of any gas or mixture of gases, or of any vapour or mixture of
vapours, or of any mixture of a gas or gases with a vapour or vapours, that part
of the apparatus which constitutes the furnace proper consisting of one or more
narrow working chambers, having thick walls, and being heated by the passage
through them of products of combustion, before they are charged with the solid
substance or mixture of substances which is to be heated in them, the entrance
into the said narrow working chambers of the said products of combustion being
arrested before the said solid substance or mixture of solid substances is charged
into the said narrow working chambers, and that solid material or mixture of solid
materials being then heated by absorption of some of the heat previously stored
up in the said walls of the said narrow working chambers, the said chambers,
(when the apparatus contains more than one of them) not communicating one with
another, but all communicating with a common combustion chamber, from which
products of combustion enter them all by the same extremity of each of them, the
products of combustion which have traversed one of the said narrow working
chambers not then traversing any of the other chambers of the series, but passing
off from the one chamber which they have traversed into other apparatus the
combination with such narrow working chambers of a movable burner, for heating
those narrow chambers by the products of the combustion of gaseous fuel; and heating
that gaseous fuel, and the air which is to burn it, in the movable burner itself, by
the products of combustion which have traversed and passed off from the narrow
working chambers of that part of the apparatus constituting the furnace proper.
Dated this 31st day of May 1886.