Improvements in the Carbonising or Destructive Distillation of Coal, Shale, Carbonaceous Tars, and similar Substances for the Pro- duction of Illuminating and Heating Gases and Water Gas, and in Apparatus therefor.
Year: 1898

page_text: Date of Application. 16th Apr.. 1898
Complete Specification Left, 16th Jan.. 1899-Accepted. 1st Apr.. 1899
Complete Specification Left, 16th Jan.. 1899-Accepted. 1st Apr. 1899
PROVISIONAL SPECIFICATION.
Improvements in the Carbonising or Destructive Distillation of Coal,
Shale, Carbonaceous Tars, and similar Substances for the Pro-
duction of Illuminating and Heating Gases and Water Gas, and in
Apparatus therefor.
We, WILLIAM YOUNG, Chemical Engineer, Priorsford, Peebles, WALTER RALPH
HERRING, Manager of the Edinburgh and Leith Gas Works, New Street, in the
City of Edinburgh, and ALEXANDER BELL, Manager, Gas Works, Peebles, do hereby
declare the nature of this invention to be as follows:-
This invention relates to the carbonising or destructive distillation of coal, shale,
carbonaceous tars and similar substances chiefly for the production of illuminating
and heating gases and it consists of an improved method or process of treating
such coal, shale and other gas producing substances by which they are rapidly.
economically and efficiently carbonised and gasified, and by which the residual
carbon can be more economically heated and employed for those purposes and for
the production of water gas.
The principle of the improved process consists in bringing the coal, shale or other
gas producing substance into intimate contact with a large mass and surface of
highly heated materials, so that the heat of the mass of material will be rapidly
transferred to the coal, shale or other gas producing substances and effect their
carbonisation and gasification.
The improved process is carried into effect in large internally heated carbonising
chambers, retorts or gas producers which may partake of various shapes and designs,
but which are rotated, oscillated or otherwise made movable, instead of being
stationary, so that the mass of coke contained in the producer may be turned over
and have fresh surfaces presented to the blast of air, and the air applied in such
a manner that the carbon can be burned directly into carbonic acid and the result-
ing heat applied to heating up the coke and the walls of the moving retort or
producer. By the movement of the producer the mass of the coke so heated and
the heated walls of the producer can be brought into intimate contact and inter-
mixture with the coal or liquid hydrocarbon which is charged into the producer to
be carbonized, and the heat stored up in the mass of coke and the producer walls
is thus more directly and rapidly transferred to the coal or liquid hydrocarbon
in effecting their gasification. The movement of the mass of hot coke inside the
producer by exposing fresh surfaces to the action of the steam enables the heat
of the coke to be more effectively used for the production of water gas when it is
so desired to apply it.
The gas producers or retorts may be of any convenient form by which the con-
tained coke can be turned over or mixed, preference is given however to cylindrical
vessels with ends more or less spherical or conical in shape, built with metal plates,
lined with fire-bricks and provided with suitable mechanical arrangements to
enable them to be slowly rotated or oscillated. They are also provided with suitable
doors and pines for the charging of the coal and liquid hydrocarbons and for the
D

page_text: discharging of the surplus coke and ash. Openings with the necessary connecting
pipes, valves, and hydraulic seals are also provided at the axes of the ends for the
introduction of the air-blast, for the escape of the spent products of combustion,
for the introduction of the steam and for drawing off the gaseous and volatile
products of distillation.
In one convenient form of apparatus the producer or retort is substantially the
same in structure as a revolving black ash balling furnace which is used in the
manufacture of soda, and it consists of a cylindrical shell of boiler plates lined with
fire bricks. This cylindrical producer is strengthened and supported by strong
rings which rest on sets of rollers; and a rotary motion is given to it by means of
a steam engine through a shaft and spur wheel which is fixed to the body of the
producer. A doorway with a gas tight cover is provided in the side of the pro-
ducer or retort for the purpose of charging in the coal and the discharging of the
surplus fixed carbon or coke resulting from the carbonization of the coal or other
substances introduced. The axes on the ends of the producer are provided with
openings. To one opening is attached, through a stuffing box, a pipe provided
with a valve for the introduction of the air blast and the outlet for the volatile and
gaseous products of carbonization to the hydraulic seal chest. Through the middle
of this pipe is also introduced a pipe for injecting tar or other hydrocarbonaceous
liquids into the producer. The opening in the axis of the other end of the pro-
ducer or retort is the outlet for the products of combustion and is provided with a
gas tight cover or door which is closed or opened by means of a lever, connecting
rod and handle. This door is attached to the lever by a central pin so that it is
free to move with the motion of the producer. The arrangement is further pro-
vided with a steam pipe which is carried along the side of the producer and is pierced
with a series of holes. Opposite these holes there are corresponding openings in
the firebrick lining so as to introduce steam amongst the highly heated carbon
when it is desired to produce water gas. This steam pipe is provided with a valve
and is connected and disconnected to the steam supply pipe each time it is used by
means of a flexible tube and couplings.
When the apparatus is first started a small fire of hot coke or coal is charged into
the producer or retort by the doorway, an air blast from any suitable fan or blow-
ing arrangement is then turned on by opening the valve on the air pipe, the
products of combustion being allowed to escape through the outlet and up the
funnel, this being continued until the whole of the fire-brick lining is thoroughly
dried. Or the drying of the brickwork and even the subsequent heating of the
producer and its contents may be brought up to the desired temperature by inject-
ing liquid fuel through the central pipe. Thereafter a large mass of coke, pre-
ferably in a state of ignition, is charged into the producer. the doorway is closed
and the producer slowly rotated so that fresh surfaces of the ignited coke are
continually presented to the air-blast. The mass of coke in the producer and the
firebrick lining are thus rapidly raised to a temperature which may be made higher
or lower to suit the purpose for which the heat has to be applied. When the
object is to produce water gas the temperature of the coke requires to be extremely
high as heat below a certain temperature fails to decompose the water into gas. When
on the other hand the object is to carbonize coal, tars or oils the temperature
requires to be lower and just such as practical trial shows is best suited for the gasifi-
tion of each particular gas-producing material. When the mass of coke and the
lining of the producer have attained the desired temperature the air blast is turned
off by closing the valve on the air pipe the producer is brought to rest with the
doorway on the top and the door on the outlet for the products of combustion is
closed. If it is intended to produce water gas the temperature of the coke and of
the lining of the producer is made extremely high and steam is then turned on into
the bottom of the producer by connecting the steam pipes by means of the flexible
tube, and the steam is passed up through the mass of incandescent coke while at
the same time the producer is kept slowly oscillating so as to present fresh surfaces
of the coke to the action of the steam. The water gas produced passes away to the

page_text: At
hydraulic seal chest and thence to the condenser, purifier and storage holder. On
the temperature of the coke falling below that suitable for the production of water
gas the steam is shut off by closing the valves and disconnecting the flexible tube.
The door on the outlet for the products of combustion is opened and the air-blast
again turned on, the rotating motion is again given to the producer and the tem-
perature of the firebrick lining and the enclosed coke is again raised to the desired
degree, when the sequence of operations already described is repeated with the
production of another quantity of water gas. Instead of repeating the water
gas producing process the lower temperature heat left after the production of so
much water gas may be more economically employed in carbonizing or gasifying
coal or liquid hydrocarbons to carburet the previously produced water gas.
the end of the water gas producing stage the necessary charge of coal is introduced
into the producer through the doorway the door being immediately closed and the
producer or retort made to slowly rotate which causes the coal newly charged to
mix and come into intimate contact with the still hot coke and firebrick lining
of the producer and thereby effect the carbonization and gasification of the coal.
When once the hot coke and fresh coal are thoroughly mixed and brought into
intimate contact, the producer or retort may with advantage be stopped rotating
as the continued motion of the mixed mass tends to produce breeze and small
coke. By thus carbonizing the coal a high temperature is applied to effect the
decomposition of the volatile products when they are given off abundantly during
the earlier stages of the carbonization, and as the volatile products evolved from
the coal diminish as the carbonizing process advances the temperature of the mass
of coke and of the firebrick lining of the producer is proportionately lower and
thus a better carbonization of the products is effected.
When oil, tar, or any other liquid hydrocarbon is to be carbonized and gasified
it is introduced by the central pipe and is injected through a nozzle and so spread
over the moving mass of hot coke, or it may with advantage in some cases be
spread over a moving mass of commingled hot coke and coal while the coal is under-
going carbonization. More particularly is this the case with coal that has a
tendency to produce a friable coke and when the liquid hydrocarbon leaves a large
residue as in the case of coal tar, the solid residue from the tar or other liquid hydro-
carbon tends to cake together and harden the coke resulting from the coal. The
volatile and gaseous products from the coal, oil, or tar, pass away from the producer
by the pipe and hydraulic seal box and to the condenser, purifier, and storage
holder where it is commingled with and carburets the water gas previously pro-..
duced. It will be understood that when water gas is not to be produced but only-
gas from coal, tar, and other liquid hydrocarbons the producer or retort and its
contained coke are heated only to the temperature appropriate to that purpose.
On the completion of the carbonization of the coal or liquid hydrocarbon the
surplus fixed carbon or coke, in excess of the quantity necessary to reheat the
producer and the contained mass of coke and to produce the desired quantity of
water gas, is discharged by opening the doorway, and then turning the producer
round so that the door will be in such a position as to allow the surplus coke to
fall out into a hutch placed underneath to receive it. The doorway is then closed
and the door on the outlet for the products of combustion is opened, the air blast"
turned on and the process of reheating and gas producing repeated alternately in
the manner already described.
The movable producer or retort as herein described may under certain conditions
in which it is desirable to effect a more direct and complete gasification of the
volatile products from the coal, tar or oil, be advantageously connected up to a
vertical stationary decomposing chamber filled with brick checker work such as
that employed and well known as the fixing chamber in ordinary water gas plant.
Under such circumstances instead of allowing the products of combustion to
escape by the opening and funnel into the air, the opening is connected by suitable
mechanical means to the inlet of such a stationary fixing chamber. This fixing
chamber is operated in the same way as is done in ordinary water gas plant, the
;
:

page_text: checker work being heated by the products of combustion coming from the movable
producer and the volatile products from the coal, tar, or oil in the same producer
being subsequently passed through and brought into contact with the hot checker
work in the manner well known with other carburetted water gas plant.
Dated this 15th day of April 1898.
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents,
62, Saint Vincent Street, Glasgow,
Agent for the Applicants.
Improvements in the Carbonising or Destructive Distillation of C.al,
Shale, Carbonaceous Tars, and similar Substances for the Pro-
duction of Illuminating and Heating Gases and Water Gas, and in
Apparatus therefor.
We, WILLIAM YOUNG, Chemical Engineer, Priorsford, Peebles, WALTER RALPH
HERRING, Manager of the Edinburgh and Leith Gas Works, New Street, in the
City of Edinburgh, and ALEXANDER BELL, Manager, Gas Works, Peebles, do hereby
declare the nature of this invention and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement:
This invention relates to the carbonising or destructive distillation of coal, shale,
carbonaceous tars and similar substances chiefly for the production of illuminating
and heating gases and it consists of an improved method or process of treating
such coal, shale and other gas producing substances by which they are rapidly,
economically and efficiently carbonised and gasified, and by which the residual
carbon can be more economically heated and employed for those purposes and for
the production of water gas.
The principle of the improved process consists in bringing the coal, shale or other
gas producing substance into intimate contact with a large mass and surface of
highly heated materials, so that the heat of the mass of material will be rapidly
transferred to the coal, shale or other gas producing substances and effect their
carbonisation and gasification.
The improved process is carried into effect in large internally heated carbonising
chambers, retorts or gas producers which may partake of various shapes and designs,
but which are rotated, oscillated or otherwise made movable, instead of being
stationary, so that the mass of coke contained in the producer may be turned over
and have fresh surfaces presented to the blast of air, and the air applied in such
a manner that the carbon can be turned directly into carbonic acid and the result-
ing heat applied to heating up the coke and the walls of the moving retort or
producer. By the movement of the producer the mass of the coke so heated and
the heated walls of the producer can be brought into intimate contact and inter-
mixture with the coal or liquid hydrocarbon which is charged into the producer to
be carbonized, and the heat stored up in the mass of coke and the producer walls
is thus more directly and rapidly transferred to the coal or liquid hydrocarbon
in effecting their gasification. The movement of the mass of hot coke inside the
producer by exposing fresh surfaces to the action of the steam enables the heat
of the coke to be more effectively used for the production of water gas when it is
so desired to apply it.
:
The gas producers or retorts may be of any convenient form by which the con-

page_text: tained coke can be turned over or mixed, preference is given however to cylindrical
vessels with ends more or less spherical or conical in shape, built with metal plates,
lined with fire-bricks and provided with suitable mechanical arrangements to
enable them to be slowly rotated or oscillated. They are also provided with suitable
doors and pipes for the charging of the coal and liquid hydrocarbons and for the
discharging of the surplus coke and ash. Openings with the necessary connecting
pipes, valves, and hydraulic seals are also provided at the axes of the ends for the
introduction of the air-blast, for the escape of the spent products of combustion,
for the introduction of the steam and for drawing off the gaseous and volatile
products of distillation.
The accompanying drawings illustrate the preferred form of apparatus employed
in carrying out the invention, Figure 1 being a side elevation, and Figure 2 a
sectional plan of the improved revolving and internally heated carbonising chamber,
retort or gas producer.
As shewn by these drawings the producer or retort is substantially the same
in structure as a revolving black ash balling furnace which is used in the manu-
facture of soda, and it consists of a cylindrical shell A of boiler plates lined with
fire bricks A. This cylindrical producer is strengthened and supported by strong
rings a which rest on sets of rollers B; and a rotary motion is given to it by means
of a steam engine C through a shaft c and gearing and a spur wheel D which is
fixed to the body of the producer A. A doorway with a gas tight cover E is pro-
vided in the side of the producer or retort for the purpose of charging in the coal
and the discharging of the surplus fixed carbon or coke resulting from the car-
bonization of the coal or other substances introduced. The axes on the ends of
the producer are provided with openings F and G. To one opening F is attached,
through a stuffing box, a pipe I provided with a valve f for the introduction of
the air blast and the outlet at F2 for the volatile and gaseous products of carboniza-
tion to the hydraulic seal chest H. Through the middle of this pipe F is also
introduced a pipe I for injecting tar or other hydrocarbonaceous liquids into the
producer. The opening G in the axis of the other end of the producer or retort
is the outlet for the products of combustion and is provided with a gas tight cover
or door G which is closed or opened by means of a lever g, connecting rod g¹
and handle g². This door is attached to the lever g by a central pin g³ so that
it is free to move with the motion of the producer. Over the opening G is placed
a funnel G2 for carrying away the products of combustion, and over the doorway E
is placed a charging hopper E for holding and delivering the coal to be carbonised.
The arrangement is further provided with a steam pipe J which is carried along
the inside of the producer A and is pierced with a series of holes. Opposite these
holes there are corresponding openings in the firebrick lining A¹ so as to provide
for the introduction of steam amongst the highly heated carbon when it is desired
to produce water gas. This steam pipe J is provided with a valve J1 and is connected
and disconnected to a steam supply pipe J2 each time it is used, by means of a
flexible tube J3 and couplings.
When the apparatus is first started a small fire of hot coke or coal is charged
into the producer or retort by the doorway E, an air blast from any suitable fan.
or blowing arrangement is then turned on by opening the valve f on the air pipe F¹,
the products of combustion being allowed to escape through the outlet G and up
the funnel G2, this being continued until the whole of the fire-brick lining A¹ is
thoroughly dried. Or the drying of the brickwork and even the subsequent heating
of the producer and its contents may be brought up to the desired temperature by
injecting liquid fuel through the central pipe I. Thereafter a large mass of coke,
preferably in a state of ignition, is charged into the producer, the doorway E
is closed and the producer A slowly rotated by means of the engine so that fresh
surfaces of the ignited coke are continually presented to the air-blast. The mass
of coke in the producer and the firebrick lining are thus rapidly raised to a tem-
perature which may be made higher or lower to suit the purpose for which the heat
has to be applied. When the object is to produce water gas the temperature of

page_text: the coke requires to be extremely high as heat below a certain temperature fails
to decompose the water into gas. When on the other hand the object is to car-
bonize coal, tars or oils the temperature requires to be lower and just such as
practical trial shows is best suited for the gasification of each particular gas-
producing material. When the mass of coke and the lining of the producer have
attained the desired temperature, the air blast is turned off by closing the valve f
on the air pipe F; the producer is brought to rest with the doorway E on the
top and the door G¹ on the outlet for the products of combustion is closed. If it is
intended to produce water gas the temperature of the coke and of the lining of
the producer is made extremely high and steam is then turned on into the bottom
of the producer by connecting the steam pipes J and J2 by means of the flexible
tube J, and the steam is passed up through the mass of incandescent coke while
at the same time the producer A is kept slowly oscillating so as to present fresh
surfaces of the coke to the action of the steam. The water gas produced passes
away to the hydraulic seal chest H and thence by the pipe to the condenser,
purifier and storage holder. On the temperature of the coke falling below that
suitable for the production of water gas the steam is shut off by closing the valves J₁
and J and disconnecting the flexible tube J³. The door G₁ on the outlet for the
products of combustion is opened and the air-blast again turned on, the rotating
motion is again given to the producer A and the temperature of the fire-brick
lining and the enclosed coke is again raised to the desired degree, when the sequence
of operations already described is repeated with the production of another quantity
of water gas. Instead of repeating the water gas producing process the lower
temperature heat left after the production of so much water gas may be more
economically employed in carbonizing or gasifying coal or liquid hydrocarbons to
carburet the previously produced water gas. At the end of the water gas pro-
ducing stage the necessary charge of coal is introduced into the producer through
the doorway E the door being immediately closed and the producer or retort A made
to slowly rotate which causes the coal newly charged to mix and come into intimate
contact with the still hot coke and firebrick lining of the producer and thereby
effect the carbonization and gasification of the coal. When once the hot coke and
fresh coal are thoroughly mixed and brought into intimate contact, the producer
or retort may with advantage be stopped rotating as the continued motion of the
mixed mass tends to produce breeze and small coke. By thus carbonizing the
cool a high temperature is applied to effect the decomposition of the volatile pro-
ducts when they are given off abundantly during the earlier stages of the
carbonization, and as the volatile products evolved from the coal diminish as the
carbonizing process advances the temperature of the mass of coke and of the fire-
brick lining of the producer is proportionately lower and thus a better carbonization
of the products is effected.
When oil, tar, or any other liquid hydrocarbon is to be carbonized and gasified
it is introduced by the central pipe I and is injected through a nozzle and so spread
over the moving mass of hot coke, or it may with advantage in some cases be
spread over a moving mass of commingled hot coke and coal while the coal is
undergoing carbonization. More particularly is this the case with coal that has
a tendency to produce a friable coke and when the liquid hydrocarbon leaves a
large residue as in the case of coal tar, the solid residue from the tar or other liquid
hydrocarbon tends to cake together and harden the coke resulting from the coal.
The volatile and gaseous products from the coal, oil, or tar, pass away from the
producer by the pipe F and hydraulic seal box H and to the condenser, purifier,
and storage holder where it is commingled with and carburets the water gas pre-
viously produced. It will be understood that when water gas is not to be produced
but only gas from coal, tar, and other liquid hydrocarbons the producer or retort
and its contained coke are heated only to the temperature appropriate to that
purpose.
On the completion of the carbonization of the coal or liquid hydrocarbon the
surplus fixed carbon or coke, in excess of the quantity necessary to reheat the

page_text: producer and the contained mass of coke and to produce the desired quantity of
water gas, is discharged by opening the doorway E, and then turning the producer
round so that the door will be in such a position as to allow the surplus coke to fall
out into a hutch L placed underneath to receive it. The doorway is then closed
and the door G on the outlet G for the products of combustion is opened, the
air blast turned on and the process of reheating and gas producing repeated
alternately in the manner already described.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is:
1. The method or process of producing heating and illuminating gases and water
gases by decomposing steam and distilling or carbonizing coal or oil or like sub-
stances in an internally and intermittently heated revolving retort or producer,
such revolving retort or producer being charged with coke, coal or other car-
bonaceous combustible, and the charge of carbonaceous matter, and the walls of
the retort or producer being heated up by the combustion of a part of the car-
bonaceous matter by a blast of air, while the retort is slowly rotated so as to turn
over the combustible and present fresh surfaces of the ignited combustible
to the air blast, and also fresh surfaces of the walls of the producer to the com-
bustion products, thereafter on the desired temperature being attained, shutting
off the air blast, and employing the heat stored up in the carbonaceous charge,
and in the walls of the retort or producer, in decomposing steam or carbonising
or distilling coal or oil, the producer being slowly rotated so as to contin-
uously present fresh heated surfaces of the carbonaceous charge, and of the walls
of the producer to the steam, coal or oil to be decomposed, carbonized or distilled
and gasified substantially as described.
2. Apparatus for the production of heating and illuminating gases by an inter-
mittent or alternating operation, consisting of a revolving retort or producer built
of metal plates and lined with brickwork and provided with a door in the side,
through which is charged the coal coke or other carbonaceous substance to be
distilled or used in heating up the retort or producer, a pipe passing through a
stuffing box in the axis of the one end of the producer for the threefold purpose
of introducing the air blast, to heat up the apparatus, to introduce the oil to be
gasified, and to draw off the gasified products, the other axial end of the producer
being provided with an opening having a vent valve for the escape of the products
of combustion during the heating up period and means for introducing. steam
through the incandescent carbon, substantially as described.
Dated this 14th day of January 1899
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents,
62, Saint Vincent Street, Glasgow,
Agent for the Applicants."