IMPROVEMENTS IN APPARATUS USED IN THE MANUFACTURE OF GAS, AND FOR OTHER PURPOSES
Year: 1879

page_text: „LETTERS PATENT to William Purves Wilson, of Braxfield Road, Brockley, in
the County of Kent, for the Invention of "IMPROVEMENTS IN APPARATUS USED
IN THE MANUFACTURE OF GAS, AND FOR OTHER PURPOSES."
Sealed the 12th August 1879, and dated the 22nd February 1879.
PROVISIONAL SPECIFICATION left by the said William Purves Wilson at
the Office of the Commissioners of Patents on the 22nd February 1879.
WILLIAM PURVES WILSON, of Braxfield Road, Brockley, in the County of Kent.
"IMPROVEMENTS IN APPARATUS USED IN THE MANUFACTURE OF GAS, AND FOR
OTHER PURPOSES."
This Invention has reference to the construction of furnaces, ovens, and flues used
for heating the retorts in such a manner as to increase the durability of the retorts,
furnaces, and ovens, and obtain greater economy in the use of fuel.
To effect these objects I arrange the retort stack with one or more main flues,
and one or more auxiliary main flues, placed on the top or underneath the stack, or
underneath the floor in front, or at the back of the retort stack. The exhaust flue
or flues of each retort setting will deliver the waste gases into one of these main
flues, and when all the retort settings in the stack are in action this main flue will
convey the waste gases direct to the chimney, but when one or more of the retort settings
are not further required for carbonizing during the season this main flue will be
checked by the partial closing of the damper at the chimney, and the auxiliary main flue,
which also communicates with the chimney, will have its damper opened sufficiently
to create a greater vacuum or draught within it than is in that of the main flue.
The auxiliary main flue communicates with each setting of retorts by an auxiliary
exhaust flue, which terminates in the setting anywhere in the neighbourhood of the
furnace, and as the vacuum or draught is greatest in the auxiliary main flue the
waste gases passing from the retort settings in action into the main flue are with-
drawn therefrom through the exhaust flue or flues into and through the retort
setting out of action into the auxiliary exhaust flue in the neighbourhood of the

page_text: furnace, thence into the auxiliary main flue, and on to the chimney. By this
arrangement the waste gases in the main flue are drawn through the retort settings
not in action in the opposite direction to that followed by the gases from the furnaces
when the retort settings are in action, thereby keeping the retorts not in action up
to a sufficient temperature by the heat of the waste gases from the retort settings
in action, and thus preventing the retorts and brickwork from being cracked and
destroyed by the shrinkage that ensues when they are permitted to cool down to
the temperature of the atmosphere, which hitherto has been the practice, as on the
approach of the summer season when less retorts are required in action, and also on
every occasion when the furnaces require to be renewed. The furnaces hitherto
under ordinary circumstances continued in action from five to seven months, then
required renewing. The retorts being destroyed by the foregoing circumstances,
they last but three seasons, or from fifteen to twenty-one months, and then require
to be replaced by new retorts.
The furnaces may be built of the ordinary form, but as an independent structure,
supported on a carriage made of iron or other suitable material, so that it will be
moveable. The space occupied in any setting of retorts by the hitherto incorporated
furnaces will be of sufficient size to receive the moveable furnace, which will occupy
exactly the same position in the retort settings as the ordinary furnaces hitherto
built with and incorporated and forming part of the brickwork of the retort setting.
On the bottom of the space to be occupied by the movable furnace plates or rails
will be laid, on which the furnace carriage will roll or slide into its position in the.
retort setting; or an enlarged ash-pan containing water may be used in place of
the plates or rails. A recess or projection may be formed in or on the brickwork
of the three interior vertical sides of this space near the bottom, which will fit into
the counterpart formed on the three sides of the moveable furnace, so as to form a
kind of male and female joint, which will be rendered air tight by fire clay or other
refractory plastic material. Air flues will be constructed in the brickwork forming
the sides and back of the furnace. At the back the side flues will join a flue running
backwards and forwards in the floor of the setting, thence be continued up the back
wall to the top, from which a perforated refractory air tube or hollow arch with
nostrils will be continued either across the centre of the furnace or around the walls
above the level of the fuel, or the flues in the side walls may be provided with
vertical nostrils communicating with the furnace. Air flues will also be formed in
the bed-plate or carriage to supply air to the side plates.
For rotort settings built in ovens supported on arches, or what are called stage
settings, the movable furnace may be of a circular or other form, and placed in the
arches underneath the retort setting, openings being made in the partition arch to
admit the fire heat from the furnace into the retort setting. The upper surface of
the furnace walls are made to fit the underside of the partition arch, and a layer
of fire clay or other material being laid thereon the furnace will be raised and the
clay compressed, forming an air tight joint all round.
Where there is sufficient depth, such as is found in the stage settings, the furnaces
may be increased in depth, and arranged to work as regenerating furnaces, provided
with the same arrangement of air flues as already described, if they should be of
the same form, but if they are of a circular or oval shape they are constructed with
an outer vertical casing of iron, having in addition an air space between the casing
and the firebrick lining of the furnace. The fuel space of the furnace will be con-
tinued parallel for a part of its height, then rapidly contracting towards the bottom
to a limited firegrate area of sufficient size to admit of the necessary quantity of air
for the conversion of the fuel into carbonic oxide.
The furnaces may be constructed with or without furnace bars, but when they
are used they will be placed underneath the furnace instead of in the furnace, and
will be supported on bearing bars carried by a movable frame, so that the bars and
frame can be lowered or removed for the purpose of clearing away any clinker
without interfering with the action of the furnace.

page_text: The movable furnaces which are used in the interior of the retort settings will
be constructed with iron fronts carrying the doors and hopper, which front will be
protected from the heat by a firebrick or fire-clay wall behind it, forming part of
the furnace, and made to fit the opening left in the front wall of the retort
setting.
Two furnaces of the ordinary or special form may be fixed in the arch underneath
the stage where double or through retort settings are used, each furnace being of
sufficient capacity to heat the double setting, so that one furnace may always be
kept in readiness to take the place of the one worn or burnt out, and permit of it
being repaired.
When any of the movable furnaces are worn or burnt out and require to be
repaired they are withdrawn, and new or repaired furnaces put into their place,
which operation is carried out within a few minutes, so that no retort setting
requires to be let down or thrown out of action for the purpose of refurnacing, as a
sufficient number of duplicate furnaces built on their carriages may always be kept
in readiness for use,
thus preventing the destruction of the retorts from the cause
just mentioned.
The furnaces may be built of firebricks, or constructed with fireclay, ground
bricks, and other refractory material; the latter being in a plastic state may be
moulded to the necessary form on the carriage, and then partially baked before
being used.
The furnaces will be constructed with hoppers on the front provided with movable
covers or doors for the purpose of supplying them with hot coke drawn direct from
the retorts.
The furnaces, ovens, and flues are not only adapted for gas retorts and ovens, but
are equally applicable to chemical and cement works.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by the
said William Purves Wilson in the Great Seal Patent Office on the 22nd
August 1879.
WILLIAM PURVES WILSON, of Braxfield Road, Brockley, in the County of Kent.
"IMPROVEMENTS IN APPARATUS USED IN THE MANUFACTURE OF GAS, AND FOR
OTHER PURPOSES.”
This Invention has reference to the construction and arrangement of ovens, flues,
and furnaces used in heating gas retorts in such a manner as to increase the
durability of the retorts, ovens, and furnaces, and to reduce the amount of fuel used
and labour employed. In carrying out my Invention I construct the retort stack
with one or more main exhaust flues, and one or more auxiliary exhaust flues, both
communicating with the chimney, and provided with a main damper to each. These
flues may be placed on the top or underneath the stack, according to the nature of
the retort settings. The usual exhaust or outlet flues from each retort setting will
deliver the waste gases into the main exhaust flue. The auxiliary main exhaust
flue is connected with the retort settings by other outlet flues opening into the
setting in the neighbourhood of the furnace. When the whole of the settings and
furnaces in the stack are at work the waste gases pass through the main exhaust
flue to the chimney in the usual way, but when one or more of the settings and
furnaces are thrown out of action the waste gases from the retort settings in action
are caused to pass through the retort settings out of action. The gases are induced
to flow in this manner by opening the dampers of the flues in the neighbourhood of
the furnace and that of the auxiliary main exhaust flue and partially closing the
damper of the main exhaust flue, so that the waste gases pass through the retort
settings out of action in the opposite direction to that when they are in action, and
thence into the auxiliary main exhaust flue to the chimney. In this way the waste
gases of the furnaces in action are utilized in keeping the retort settings out of
action up to such a temperature as prevents any shrinkage occurring either in the
retorts or the surrounding brick work, and thereby preventing their destruction.
There are several modifications of the above arrangement of flues for effecting the
same purpose, but which are dependent upon the nature or form of the retort settings
and ovens. A single range of ovens in a stack provided with one chimney may
have dampers placed in the main exhaust flue between each retort setting, and the
furnaces of the settings out of action temporarily connected by a connecting flue,
so that the waste gases from the settings furthest from the chimney are caused to
pass back through the settings, and thence into the furnaces, and up through the
other settings. Each furnace in action will therefore supply sufficient waste heat
to keep up the temperature of two or three settings out of action.
The furnace is constructed as an independent structure, supported on a carriage
made of iron or other suitable material, so that it can be readily removed from its
position in the setting when worn out, and replaced by a repaired or new furnace,
without interfering either with the brickwork of the setting or stopping the charging
of the retorts. By these means the retorts may be continued in action for any
length of time without requiring to be thrown out of action for the purpose of
having the furnaces repaired or renewed.
When the retort settings are built on the ground level the furnace carriage is
arranged to roll or slide into its position on rails or plates laid in the furnace space
in the interior of the setting, and when the settings are built in ovens supported
on arches or what are called stage settings, the movable furnaces may be placed in
the archway underneath the retort ovens, and the rails or plates laid on the lower
floor, the furnace heat passing up through a slit or opening in the arch forming the
floor of the setting.
The furnaces for stage settings when placed in the archway underneath may be

page_text: constructed of a circular or other form, and cased with sheet or plate iron, having
an air space between the casing and the brickwork forming the sides of the furnace
The upper surface of the furnace will be constructed to fit the underside of the oven
floor arch, and in placing the furnace in its position fireclay or other plastic material
is laid on the top and compressed by raising the furnace a sufficient height to obtain
an airtight joint all round; or the archway may be filled up, leaving a space of
sufficient size to receive the movable furnace.
In constructing furnaces according to my Invention for heating retort settings on
the ground level, the brickwork of the furnace is built on a rectangular carriage
mounted on wheels, and having a trough which is continued along the two sides
and across the back end, with the firegrate between the sides. Small orifices are
made in the inner sides of the trough near the top, which lead into the furnace
above the firegrate, to permit of the steam generated from the water in the trough
to pass into the furnace. The brick work of the sides and back end overhangs the
interior sides of the trough so as to contract the furnace to a lesser area than that
of the firegrate for a portion of its height, after which it is increased by stepping:
back the brickwork as it rises towards the top. In the back and side walls one or
more air flues are formed, having orifices or nostrils leading from them into the
furnace, the air supply being regulated by dampers placed on the front end of the
sile flues as they pass through the front frame of the furnace. The front frame of
the furnace is provided with two doors, the upper one being used for supplying the
furnace with fuel, the lower one for obtaining access to the fire bars for removing
the clinker. When furnaces of this form are used for stage settings, the coke as
drawn from the retorts is supplied hot through a hopper level with the stage floor,
and passes through the front wall of the retort setting above the furnace. When
this form of furnace is required to be made larger than usual, so that one of
thein is sufficient for a through or double setting, it is provided with one or more
bollow fire bars placed nearly on a level with the bottom of the air flues in the
furnace walls, and it or their sides are pierced near the top with orifices to allow
of the steam generated from the water they contain to pass through into the furnace,
and thus form a furnace with an upper and lower firegrate.
The ashpan, which may form a part of the trough, or be attached to the
underside of the same, is continued through the front frame a sufficient length
to carry a damper door for the purpose of regulating the supply of air to the lower
firegrate.
When the height of the furnace space in a retort setting is too limited to permit
of the ash-pan being attached to the underside of the trough carriage it is placed
in the floor of the furnace space, and its upper horizontal edges are planed true.
A corresponding planed face is also formed on the underside of the trough, so that
when the furnace is placed in its position over the ashpan it is lowered to rest upon
the planed faces, and form an air tight joint all round by a depression being formed
at that point of the rails where the carriage wheels come when in its position.
The front frame of the furnace is made to project beyond the furnace on the two
vertical sides and top to form a flange of larger dimensions than the opening in the
front wall of the setting. On the face of this flange fireclay or other material is
placed, so that when the furnace is pushed into its position the projecting flange is
forced against the face of the front wall, thus constituting an air tight joint.
space between the lower edge of the front frame and the floor is filled up with
brickwork after the furnace has been placed in its position.
The
The furnace bars of the lower grate may be supported on a movable frame, and
arranged to be withdrawn when covered with clinker, and replaced by a duplicate
set of clean bars; or the bars may be arranged cylindrically, and carried upon a
central spindle provided with bearings so that the fouled bars could be moved round
out of the furnace, and the clean bars introduced. Also bars may be constructed of.
links, forming an endless chain carried on drums, one at the front and the other at
the back end of the furnace, and as the firegrate area became fouled with clinker
it would be moved forward and cleaned..

page_text: When one furnace is used for a through or double setting two may be arranged
so that one of them could always be at work, and the other kept in readiness to
be put in action to allow of the one burnt out being repaired so as to keep the
setting in continuous action. In this case it is not necessary to make them portable
or movable.
In consequence of the furnaces being constructed as described, each is capable of
being converted from an atmospheric furnace to that of partly an atmospheric and
partly a regenerative one, by regulating the supply of air to the firegrate and air
flues. It may also be made to act wholly as a regenerator, this being effected by
increasing the depth of the furnace and the distance from the lower firegrate to the
orifices communicating with the air flues.
In order that the foregoing may be more easily understood Drawings are attached
hereto, of which the following is a description, the illustrations showing the appli-
cation of the Invention to the manufacture of gas:-Fig. 1 is a front elevation of
the furnace; Fig. 2, a vertical transverse section through A, B, Fig. 3; Fig. 3 is
a vertical longitudinal section through the centre of the furnace; Fig. 4, a horizontal
section through C, D, Fig. 1, and shows a plan of the trough; Fig. 5 is a plan.
E is the furnace front; F is the fuel door; and G, G, are the clinkering doors;
H, H, are the damper doors of the air flues; I is an opening or orifice through which
water is supplied to the trough J; and K is the ashpan; L, L, are the brackets,
and M, M, the wheels which support the carriage on the rails N, N, and on which
the carriage wheels roll; 0, 0, are ribs to strengthen the trough, and P is the cover
of the trough, Q being the water space in the trough J; R, R, are orifices for
admitting into the furnace the steam generated in the trough; S, S, are the furnace
bars; T, the dead plate, and U the bearing bar; V is the back, and W the side
walls of the furnace; X, X, are the horizontal air flues, and Y, Y, are the vertical
openings or nostrils communicating between the air flues and interior of furnace;
Z is a fireclay lump forming dead plate; a is the arch or bridge over upper door-
way; b, front wall of the retort setting; e, projection beyond the opening, forming
a flange joint; and d, a double tie bar, shown in dotted lines, for securing the furnace
front to the trough; e is the hopper through which the fuel is supplied to the
furnace from the stage floor; f is the sand lute, and g the door of the hopper,
while h is the damper door in front of the ash-pan.
Fig. 6 is a vertical transverse section of the trough, showing the ash-pan separated
from it by the planed faces at i, and the wheels working in an indent formed in
the underside of the trough, so as to suit retort settings having furnace spaces limited
in height. This Fig. also shews at j the mode of making the horizontal joint some-
times found necessary. This is accomplished by a flange projecting from the back
end and sides of the trough, and a projection of brickwork formed on the interior
sides of the furnace space in the settings.
It will be seen from the foregoing that although reference is made especially to
furnaces to heat gas retorts the plan is equally well adapted for furnaces for heating
many other kinds of apparatus.
b
Having now described and particularly set forth the nature of this Invention,
and the manner in which the same is or may be used or carried into effect, I would
observe in conclusion that I do not confine or restrict myself to the precise details
or arrangements which I have described or referred to, as variations may be made
therefrom without deviating from the principles or main features of this Invention,
but what I consider to be novel and original and therefore claim as the Invention
secured to me by the hereinbefore in part recited Letters Patent is,―
Firstly. The construction of movable furnaces, as herein described and shown on
the Drawings, and their application to all forms of retort settings or similar appa-
ratus, so that worn or burnt out furnaces can be replaced without requiring the
retorts to be cooled down or cease working.
Secondly. The arrangement of main auxiliary and subsidiary flues, by which the
waste gases from the retort furnaces in action are utilized in keeping the retorts
not at work up to such temperature as prevents them..and the surrounding brick-

page_text: work from shrinking and cracking, as herein described, and shown on the
Drawings.
Thirdly. The construction of fixed furnaces in the lower arches of stage settings,
as herein described, and shown on the Drawings.
Fourthly. The construction and arrangement of both simple and regenerating
furnaces, as herein described, and
Fifthly. The construction and arrangement of fire bars and their frames, as herein
described, and shown on the Drawings.
In witness whereof, I, the said William Purves Wilson, have hereunto set
my hand and seal, this Twenty-second day August, in the year of our
Lord One thousand eight hundred and seventy-nine.
D WITT NOT
W. P. WILSON (L.D.)