Im- PROVEMENTS IN THE DESTRUCTIVE DISTILLATION OF Coal, Shale, and OTHER BITUMINOUS SUBSTANCES FOR THE PRODUCTION OF ILLUMINATING Gas, and of OILS." PROVISIONAL SPECIFICATION
Year: 1872

page_text: ETTERS PATENT to William Young, Manager of the Chemical
Works, Magdalen Bridge, Andrew Scott, Manager of the Mussel-
burgh Gas Works, Musselburgh, both in the County of Mid
Lothian, and William Walker Stephens, of Leith, in the County
of Mid Lothian, Executor of Peter Brash, late of Leith, Soap,
Candle, and Oil Manufacturer, deceased, for the Invention of "Im-
PROVEMENTS IN THE DESTRUCTIVE DISTILLATION OF Coal, Shale, and OTHER
BITUMINOUS SUBSTANCES FOR THE PRODUCTION OF ILLUMINATING Gas, and of
OILS."
PROVISIONAL SPECIFICATION left by the said William Young, Peter
Brash, and Andrew Scott at the Office of the Commisioners of
Patents, with their Petition, on the 21st August 1872.
We, WILLIAM YOUNG, Manager of the Chemical Works, Magdalen
Bridge, PETER BRASH, of Leith, Soap, Candle, and Oil Manufacturer,
and ANDREW SCOTT, Manager of the Musselburgh Gas Works, Mussel-
burgh, all. in the County of Mid Lothian, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN THE DESTRUCTIVE DISTILLATION

page_text: OF COAL, SHALE, AND OTHER BITUMINOUS SUBSTANCES.-FOR-THE PRODUCTION: OF
ILLUMINATING GAS, AND OF OILS," to be as follows:-
:-
In the destructive distillation of coal, shale, and mixtures of coal with
hydrocarbon oils and other bituminous substances for the production of
illuminating gas, we employ a retort or distilling vessel so arranged that
the gases and vapours given off from the bituminous substance which is
being distilled in one part of the retort are caused to pass in a downward
direction through the heated residue or coke of a previous chargo, tho
effect of which is to cause those vapours to be converted into good
permanent gas, which if otherwise allowed to escape would be condensed
into tar.
The retort consists of a vessel set in a vertical position of any
convenient form, by preference either cylindrical or oval, and slightly
conical to allow the coal, shale, or other material to pass through it.
The lower end of the vessel is caused to dip into a trough of water to a
depth sufficient to hinder the gases from escaping, and a sufficient space
is left between retort and bottom of trough for removal of coke or
residue. The top of the vessel is supplied with a hopper and valvo
or other suitable arrangement by which the coal, shale, or other material
may be charged, and the opening hermetically scaled. The outlet for
the gases is placed a few inches above the water in trough. The retort
is enclosed in brickworks and heated by a furnace.
-To work the retort the trough at the bottom is filled with water, and
as much coke or residue is put into the retort as to fill it a little abovo
the outlet for gas. As soon as the retort is brought to a bright red
heat the bituminous substance to be distilled into gas is put in, the
vapours and gases from which pass in a downward direction to the
outlet through the previously charged residue, and are thereby converted
-into-permanent gases. As soon as the first charge is worked off a
quantity of .coko or residue, about-equal to the bituminous substanco
previously charged, should be withdrawn at the bottom and a fresh
charge put in at top, the gases and vapours from which will pass through
-the heated residue or coke of the previous charge. This process is
repeated, the bituminous substance of a former charge becoming after
distillation the heated residue through which the gases and vapours from
the next charge must pass. In the destructive distillation of coal, shale,
and other bituminous substances for the production of oils, the residue
or coke contains in many cases so little fixed carbon and so much ash
:

page_text: that it cannot be used for heating the retorts or distilling vessels as they
are at present arranged.
In order to make the said coke or residue available we employ an
arrangement of retort or distilling vessel by which the shale, coal, or
other material may be introduced at the one end and drawn off at the
other into a combustion chamber or furnace, and we cause the gases
given off from the substance being distilled (after the oils have been
removed by the condensers) to circulate through the retort by a pipe
from the terminal of the condenser back into the bottom of the retort.
-
An exhaust of any suitable kind, by preference a jet of steam, is
introduced in the outlet for oil vapours from the retort. The surplus
gases are allowed to escape into the combustion chamber from the
bottom of the retort, which has the effect of excluding the air or
products of combustion, thereby improving the oils and also assisting the
distillation.
The retort or distilling vessel may be of any convenient form, and
placed either in a vertical or horizontal position, but we prefer one
similar to that already described above for the manufacture of illu-
minating gas, only instead of a water trough at bottom there is a sliding
damper or other arrangement to retain the substance being distilled, and
a furnace or combustion chamber built of brick or other suitable
material into which the spent residue or coke falls and is consumed.
In heating the retort there is also a door by which the ash or consumed
residue is removed. The outlet for oil vapours is also placed on the
side of the retort, but further from the end; the whole is enclosed in
brickwork with suitable flues, and the spent products of combustion are
carried off into chimney. The condensing apparatus for oil vapours may
be similar to that in use.
To work the retort it is first heated by coal or other fuel thrown into
combustion chamber till it is brought to a dull red heat (visible only
in the dark). The substance to be distilled is then introduced by the
hopper and valve or other arrangement at the top, and as soon as the
oils begin to be produced the exhaust is set to work. As soon as one
charge becomes exhausted it is drawn off into the combustion chamber,.
and it supplies heat for the distillation of the next charge, which should
immediately be introduced at the top.

page_text: -
SPECIFICATION¨in pursuance of the conditions of the Letters Patent;
filed by the said William Young, Andrew Scott, and William
Walker Stephiens in the Great Seal Patent Office on the 21st
February 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, WILLIAM
YOUNG, Manager of the Chemical Works, Magdalen Bridge, ANDREW
SCOTT, Manager of the Musselburgh Gas Works, Musselburgh, both in
the County of Mid Lothian, and WILLIAM-WALKER STEPHENS, of Leith,_
in the County of Mid Lothian, Executor of Peter Brash, late of Leith,
Soap, Candle, and Oil Manufacturer, deceased, send grecting.
]
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-first day of August, in the year
of our Lord One thousand eight hundred and seventy-two, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto us, the said William Young, Andrew Scott, and William 1
Walker Stephens, Her special license that we, the said William Young,
Andrew Scott, and William Walker Stephens, our executors, adminis-
trators, and assigns, or such others as we, the said William Young,
Andrew Scott, and William Walker Stephens our exccutors, adminis-
trators, and assigns, should at any time agree with, and no others; from 2
time to time and at all times thereafter during the term therein
expressed, should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, -the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN THE
DESTRUCTIVE DISTILLATION OF COAL, SHALE, AND OTHER BITUMINOUS SUBSTANCES
FOR THE PRODUCTION OF ILLUMINATING GAS, AND OF OILS," upon the condition
(amongst others) that we, the said William Young, Andrew Scott, and
William-Walker--Stephens,_our_executors or administrators, by an
instrument in writing under our or their hands and seals, or under tho
hand and scal of one of us or them, should particularly describe and
ascertain the nature of the said. Invention, and in what manner the same
was to be performed, and cause the-same-to-be-filed_in_the_Great_Seal_
Patent Office within six. calendar months next and immediately after
the date of the said Letters Patent.
NOW KNOW YE, that we, the said William Young and William

page_text: hereby declare the nature of the said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement thereof, that is to say :—
This Invention has for its object improvements in the destructive
distillation of coal, shale, and other bituminous substances for the pro-
duction of illuminating gas and of oils.
In the destructive distillation of coal, shale, and mixtures of coal with
hydrocarbon oils and other bituminous substances for the production of
illuminating gas, a retort or distilling vessel is employed; it is so
arranged that the gases and vapours given off from the bituminous
substance which is being distilled in one part of the retort are caused to
pass in a downward direction through the heated residue or coke of a
previous charge, the effect of which is to cause those vapours to be con-
verted into good permanent gas, which if otherwise allowed to escape
would be condensed into tar.
The retort consists of a vessel set in a vertical position of any con-
venient form, by preference either cylindrical or oval and conical to
allow the coal, shale, or other material to pass through it. The lower end
of the vessel is caused to dip into a trough of water to a depth sufficient
to hinder the gases from escaping, and a sufficient space is left between
the retort and the bottom of the trough for the removal of coke or
residue. The top of the vessel is supplied with a hopper and valve or
other suitable arrangement by which the coal, shale, or other material
may be charged and the opening hermetically sealed. The outlet for the
gases is placed at a convenient distance above the water in trough. The
retort is enclosed in brickwork and heated by a furnace.
In the destructive distillation of coal, shale, and other bituminous
substances for the production of oils, the residue or coke contains in
many cases so little fixed carbon and so much ash that it cannot be used
for heating the retorts or distilling vessels, as they are at present
arranged.
In order more especially to make the said coke or residue available,
the retort or distilling vessel is arranged so that the shale, coal, or other
material may be introduced at the one end and drawn off at the other
into a combustion chamber or furnace, and the gases given off from the
substance being distilled (after the oils have been removed by the con-

page_text: densers) are caused to circulate through the retort by a pipe or pipes
from the terminal of the condenser back into the bottom of the retort.
An exhaust of any suitable kind, by prèference a jet of steam, is intro-
duced in the outlet for oil vapours from the retort. The surplus gases
are allowed to escape into the combustion chamber from the bottom of
the retort, which has the effect of excluding the air or products of com-
bustion, thereby improving the oils and also assisting the distillation.
.
Figure 1 is a longitudinal section of a retort or distilling vessel set in
an oven, and suitably arranged for the production of illuminating gas.
Figure 2 is a plan partly in section ;. Figure 3 is a longitudinal section;
Figure 4 is a front elevation, partly in section, of the same. The sections, 1
Figures 1 and 3, are taken respectively on the lines 1, 1, and 2, 2; in
Figure 2. The same letters indicate the same parts in all the above
Drawings. a, a, are the outer walls of the oven; the space which they
enclose is divided by screen walls. b, which separate the fire chamber c
from the retort chambers d, d. At the lower part of the fire chamber are 2
grate bars c³, which are supplied with fuel by the fire doors c³, and beneath
the grate bars are the ash-pits c³. The heat and products of combustion
from the fires pass through the openings 6' in the screen walls 6 into the
retort chambers, whence the products escape on the further side of the
retort chambers into the underground flue e; leading to a chimney; e¹ is 2
a damper for regulating the draft. In each of the retort chambers are
two retorts f, which have feeding hoppers f¹ with closely fitting valves.ƒ³
at the top. The retorts may be either of clay or iron, and both are
shown in the Drawings; f; fare-the-outlets-from-the-retorts; and
9, 9, are pipes. leading from them to the hydraulic main. The rotorts 3
are quite open at the bottom, and they dip into the water troughs h.
г
-In-working-the-above-arrangement for the destructive distillation of
coal, shale, and other bituminous substances for the manufacture of
illuminating gas the water trough hi at the bottom of the retort is filled
with water, and coke is charged. by the hopper f¹ and valve fi at the 3
top to fill the retort f to a little above the outlet for gases f³. Fire is
now placed in the furnaces by the doors o³, and the heat kept up. The

page_text: retorts are soon brought to a bright red heat by the products of com-
bustion passing through the port holes 6' in the screen wall at the side
of the furnaces, and around the retorts. The substance to be distilled is
now charged into the retorts, where it is immediately acted on by the
heat, and gives off its volatile products in the form of gases and oil
vapours; these pass downwards through the heated coke previously
charged, and are thereby converted into permanent gases; at the same
time the water which is evaporated from the trough inside the retort
in passing upwards through the highly heated cokė is decomposed, the
hydrogen combines with the richer gases as they are formed from the
oils, and assists in making them more permanent. The gases are drawn
off by the outlet pipe f³, and transmitted by the pipe to the hydraulic
main, and thence by the main pipe to be condensed and purified by the
usual mode. The evaporated water from the trough which escapes
decomposition assists in keeping the outlet pipe f³ from choking. As
soon as the first charge has been exhausted of its gas producing elements,
or nearly so, a quantity of coke sufficient to allow the residue from the
bituminous substance to sink or fall down to a little above the outlet
pipe for gases is withdrawn out of the water trough h at the bottom by
means of a rake, and a fresh charge is immediately introduced into the
retorts at the top, the gases and vapours from which must before
reaching the outlet pass through the coke or residue of the previous
charge. The coke or residue from one charge of bituminous substance
thus becomes the medium through which the gases and oil vapours from
the succeeding charge have to pass.
Figure 5 is a longitudinal section of distilling apparatus for the pro-
duction of oils; a condenser for condensing the oils is represented in
elevation, and the section is taken on the line 1, 1, in Figure 6; Figure 6
is an horizontal section taken on the line 2, 2, in Figure 5; Figure 7 is
a vertical section taken on the line 3, 3, in Figure 6; Figure 8 is a front
elevation partly in section. The same letters refer to the same parts in
the above-mentioned Drawings. a, a, are the walls of the oven; they
enclose a chamber a', at the bottom of which is the bed upon which the
retorts b, b, are set. The upper part of each retort at 6¹ is of iron,
the lower part b³ of clay, and beneath it a hole is left in the bed of the
chamber, and this hole is the mouth of the combustion chamber or
furnace c. These combustion chambers have fire-bars c¹, ash-pits c³, and
fire doors c³; d, d, are the mouths of flues leading out of the combustion

page_text: chamber c into the retort chamber a'; e is a flue leading downwards
from the centre of the retort-chamber to tho-underground. passage f
which connects with a chimney; f¹ is a damper. There are partitions
in the retort chamber, which compel the products from the combustion
chamber c to rise above the parts 6 of the retorts before they can reach
the flue e. At the top of each retort is the feeding hopper and valve b³;
the valve is luted to make it air-tight; & is the outlet from the retort to
the condenser k; which may be of ordinary construction; " is a steam
jet, which induces a draft out of the retort into the condenser; k¹ is the
oil outlet; and ², the outlet for the uncondensed-gases. The latter com--
municates with the pipe, having stop cocks at h¹ and h²; this pipe leads
back into the lower part of the retort at a point 6**; i, i, are auxiliary
furnaces or fire-holes.
i
In working the above arrangement of retorts or distilling vessels for
the destructive distillation of shale and similar bituminous substances
for the obtainment of oils, a fire is first kindled in the combustion
chambers c, c, the heated products from which passing through-the flucs
d and round the retorts 6 soon bring them to a dull red heat. The
draught is regulated by the damper f¹ placed in flue fleading to
chimney. Spent shale or other similar substance containing sufficient.
fixed carbon to keep up the heat in the oven is then charged by the
openings at top of the retorts until the combustion chamber c and
retorts 6 are filled a little above the gas inlet b**. The substance to be
distilled is then charged till the retorts are full, the covers or valves 6ª
are then placed on the openings and luted with fire-clay or other suitable
material. In a short time volatile matters are given off from the
bituminous substance which shew themselves at the flucs d at the
bottom of the retorts. The exhaust jets are then set to work, this
draws off the volatile matters from the retorts by the outlet pipes 6* into
the condensers where they are condensed and drawn off at the outlet-k'.-
The permanent gases soon shew themselves at the-stop cocks which
should be then shut and the stop cocks h³ opened, this allows the gases.
to pass by the pipe back into bottom of the retorts 6 at 6** The
gases on entering the retorts separate into two streams, the one passing
upwards through the bituminous substances to the outlets for oil vapour 3
b', thereby removing oil vapours which would otherwise find their way to
combustion chambers é and be consumed, the other passing downwards:
into the combustion chambers c where it is consumed and assists in

page_text: keeping up the heat necessary for the distillation. Thus the excess of
gas is constantly disposed of, and these gases also exclude the air from
the retort, which if allowed to enter would injure the oils.
It will readily be seen from the above description that a part of the
gas is continuously circulated through the retort and condensers, and
that the surplus gas is allowed to escape into the combustion chamber.
As soon as the first charge of the bituminous substance is exhausted
of its volatile matter, the spent residue or other substance is withdrawn
from the combustion chambers by the door c³; this allows the coke or
residue from the shale or other bituminous substance to take its place
in combustion chamber and lower part of retort, the fixed carbon of
which coke or residue in being consumed supplies heat for the des-
tructive distillation of the next charge which should be immediately
introduced. This process is repeated continuously and the coke or
residue of one charge supplies heat for the next, and so on.
As some shales and other bituminous substances contain less fixed
carbon in their residue than what is necessary for their destructivo
distillation, it is requisite in such cases to burn fuel in the auxiliary firo
holes i, sufficient to replace the deficiency, and even when the fixed
carbon is sufficient for continuous working these fire holes have to be
used in the case of the retorts standing during the Sunday or holiday to
bring up the heat at starting.
Having now described the nature of the said Invention, and the
manner of performing the same, we would remark that we do not confine
ourselves to the exact details described, but what we do claim is,―
First. The destructive distillation of coal, shale, and other bitu-
minous substances for the obtainment of illuminating gas by causing the
bituminous substance to give off its volatile products in the form of oil,
vapours, and gases, and afterwards conveying the said vapours and
gases through the highly heated residue from a previous exhausted or
nearly exhausted charge in the presence of hydrogen and water vapour,
all substantially as described.
Second. The destructive distillation of coal, shale, and other bitu-
minous substance for the obtainment of oils by the combustion of their
residue, or coke, in a combustion chamber in communication with
the retort, the products of distillation being prevented from entering
the combustion chamber, and the products of combustion from entering

page_text: the retort by means of gas or gases, more particularly those gases
generated from the substance being distilled, all substintially as
described.
Third. We claim the general arrangement of apparatus for the
destructive distillation of coal, shale, and other bituminous substances
for the production of illuminating gas, and of oils, substantially as
described.
In witness whereof, we, the said William Young, and William
Walker Stephens, have hereunto set our hands and scals, this
Twelfth day of February, in the year of our Lord One thousand
eight hundred and seventy-three.