IMPROVEMENTS IN DISTILLING COAL SHALE FOR THE PRODUCTION OF OIL AND GAS, AND IN THE
Year: 1874

page_text: LETTERS PATENT to John Bell, of Wishaw, in the County of Lanark,
;
North Britain, Engineer, for the Invention of "IMPROVEMENTS IN
DISTILLING COAL SHALE FOR THE PRODUCTION OF OIL AND GAS, AND IN THE
"
Scaled the 25th September 1874, and dated the 23rd May 1874.
PROVISIONAL SPECIFICATION left by the said John Bell at the
Office of the Commissioners of Patents, with his Petition, on the
23rd May 1874.
I, JOHN BELL, of Wishaw, in the County of Lanark, North Britain,
Engineer, do hereby declare the nature of the said Invention of "Iм-
PROVEMENTS IN DISTILLING COAL SHALE FOR THE PRODUCTION OF OIL AND GAS,
AND IN THE APPARATUS EMPLOYED THEREIN " to be as follows, that is to
say :-
This Invention, which relates to improvements in distilling coal shalo
and other substances for the production of oil and gas, and in the
apparatus employed therefor, consists in the employment of a tubular

page_text: retort fixed in a horizontal position or at a suitable angle, and containing
a shaft so constructed that the shaft may be made to revolve in bearings at
each end of the retort, the said shaft carrying portions of a screw thread
and also flat blades, each portion of the screw thread consisting of one
complete turn of the screw, and the portions of screw thread and the flat
blades alternating along the shaft. The thread of the screw and the edge
of the blades are to be formed so as nearly to touch the inner surface of
the retort but yet to revolve easily therein. The object of the portions of
screw is to move the charge forward from one end of the retort to the
other, and that of the blades is to turn it over repeatedly in its progress
onward. The screw blades are perforated with holes to allow the gases
gencrated to travel along the retort to the eduction pipe. The shaft is
caused to revolve in the cylinder by a revolving tangent screw or other
gearing driven by steam or other power.
The material to be distilled is either roughly ground or reduced to a
finer grain as the material may require, and it is charged into the
retort at one end from a vertical hopper having a revolving feed, the size
of the feed being so proportioned to the dimensions of the retort and
pitch of the screw, and the rapidity of the revolution of the feed being
so proportioned to that of the screw shaft within the retort that the
retort shall not at any time be choked by too great a charge of material,
but room left for the free evolution of the gases. The retort ought not
at any time to contain much more than half the quantity of charge
which might be forced into it. The revolution of the shaft carries the
charge forward and turns it over repeatedly in its progress.
An eduction pipe for the gases is provided at the other end, and the
condensible and uncondensible gases are collected and treated according
as illuminating gas or oil is wanted, in the usual way.
The spent shale on arriving at the end of the retort is made to fall
down a vertical pipe fitted on to the neck or end of the retort and thence
into a horizontal pipe or passage, along which the spent shale is drawn
or pushed by a revolving screw, the said horizontal pipe or passage being
sealed at the end towards which the spent shale travels, and at which it.
is thrown out into bogies or wagons by being made to rise in a curve
above the level of the rest of the pipe, so that the spent shale itself
dry seals the pipe, or the pipe may be water sealed in the ordinary
way.

page_text: Retorts of the kind hercin-before described may be placed together in
sets of two, three, or more in a bench or oven in the ordinary manner.
When it is desired to make illuminating gas, retorts of the kind
hercin-before described are used in the first stage to drive off the gases
from the material employed, and these gases are then by an exhaust.
drawn from the aforesaid retorts and forced through pipes into the usual
gas retorts, generally made of clay, where a very high degree of tempe-
rature converts the whole of the gases into permanent illuminating gas,
which is led away into a gasometer for use. These gas retorts I place in
such a position relatively to the other retorts first above mentioned as
will permit the gas from the gas retorts, when it is not desired to collect
it for illuminating purposes to be led into the oven or bench in which the
said other retorts are set, and be burned there in order to heat the said
other retorts.
When ground coal is used in the retorts for making illuminating gas,.
the charge after passing through the first set of retorts may be converted
by mixing it with tar or other suitable substance into what is commonly
known as Patent fuel.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Bell in the Great Seal Patent Office on the
23rd November 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
BELL, of Wishaw, in the County of Lanark, North Britain, Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing. date the Twenty-third day of May, in the year
of our Lord One thousand eight hundred and seventy-four, in the
37th year of Her reign, did, for Herself, Her heirs and successors
give and grant unto me, the said John Bell, Her special license that
I, the said Jolin Bell, my executors, administrators, and assigns, or
such others as I, the said John Bell, my executors, administrators,
or assigns, should at any time agree with, and no others, from time to
time and at all times thereafter during the term therein expressed,

page_text: 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 DISTILLING COAL SHALE
AND OTHER SUBSTANCES FOR THE PRODUCTION OF OIL AND GAS, AND IN THE APpa-
RATUS EMPLOYED THEREFOR," upon the condition (amongst others) that I,
the said John Bell, by an instrument in writing under my hand and
seal, 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 I, the said John Bell, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement, reference being had to the accompanying Drawings
and to the letters and figures marked thereon, that is to say :-
My said Invention, which relates to improvements in distilling coal
shale and other substances for the production of oil and gas, and in the
apparatus employed therefor, consists in the employment of a tubular
retort fixed in a horizontal or inclined position, and containing a revolving
shaft, which carries a screw thread or portions of a screw thread, and is
also provided with flat blades or stirrers, by which the material in the
retort is stirred or agitated while it is being advanced from one end of
the retort to the other by the action of the aforesaid screw thread or
portions of a screw thread.
The material is charged into the retort at one end from a hopper
provided with a revolving feed, and the resultant gases and spent material
are discharged at the other end of the retort.
The firing of the retort is in part accomplished by utilizing the non-
condensible gases, as herein-after described, or in the manufacture of
illuminating gas; part of the gas evolved in the retort may be used for
heating the same.
And in order that my said Invention may be properly understood I
now proceed more particularly to set forth the system, mode, or manner
in or under which the same is or may be used or practically carried into

page_text: effect, reference being had to the annexed Sheet of Drawings, and to
the letters and figures marked thereon, that is to say :-
Figure 1 on the annexed Sheet of Drawings is a front elevation of a
bench of three retorts constructed and fitted with apparatus in accordance
with my said Invention; Figure 2 is a transverse section of the same on
the line a, b, Figure 3, which is a plan; Figure 4 is a longitudinal
section on the line c, d, Figure 3, while Figure 5 is an end elevation,
of the retorts with a portion of the apparatus drawn in section on the.
line e, f, Figure 4.
As shewn by these Figures three tubular retorts A, B, C, are placed in
a horizontal position within a suitable brick setting, but any greater
or less number of such retorts may be so placed, or they may be
inclined at any suitable angle. The retorts are supported at both ends
by plates D, D', which are in their turn supported by the aforesaid brick
setting. Throughout the centres of the retorts A, B, C, shafts E extend,
which are capable of revolving, and upon which are fixed portions F of
a screw thread and also flat blades or stirrers G situated between the said
portions of screw thread. The shafts E are supported at one end in
bearings formed in the covers H of the retorts, while their other ends
are carried in bearings I placed within the retorts, as shewn: The
shafts E derive motion from a steam engine J or other suitable motor,
upon
the crank shaft of which is fixed a spur pinion K gearing with the
spur wheel L fixed upon the shaft M, which is connected (preferably by
a "wobbler" coupling) to another shaft N, carrying a tangent screw O
and supported in bearings formed in pillow blocks upon the ends P of
the retorts. The different tangent screws upon the several retorts are`
connected to each other, preferably by "wobbler couplings, and gear
with worm wheels Q fixed to the projecting ends of the shafts E, which
are thereby actuated.
"
The upper parts of the ends P of the retorts are formed with flanged
ports or chests R, and superposed and bolted thereto are boxes S con-
taining the revolving feeds T, which are actuated from the shafts N,
shewn separately at Figure 4, by means of the eccentrics U and
pawls V, the latter of which gear into the teeth of wheels W fixed upon
the same axis with the revolving feeds T, as shewn more particularly at
Figure 4. The upper parts of the castings S are provided with:
hoppers X, into which the material to be fed to the retorts is charged.

page_text: The lower parts of the opposite ends Y of the retorts are provided
with ports or passages Z, which are connected with a horizontal
cylinder g, (Figures 3, 4, and 5,) within which a traversing screw or
creeper / rotates, which may be composed of a continuous screw thread
or of portions of a screw thread, and provided with stirrers or blades
after the manner of the traversing screws or creepers herein-before
described as occupying the retorts A, B, C. The screw his fixed to a
shaft i, which is carried at one end in a sleeve formed on the cover j, and
at the other end in a bearing / fixed within the cylinder g, as shewn.
Upon that end of the shaft i which projects through the sleeve on the
cover j a bevil wheel is fixed gearing with a corresponding bevil
wheel m fixed on the inclined shaft n, which is driven from the shaft M
by the bevil wheels o, p. To that end of the cylinder g opposite from
the cover is bolted another cylinder q of equal diameter with the.
cylinder g, but placed at an angle relatively therewith; and to the said
cylinder q is bolted another cylinder lying in a plane parallel to that of

page_text: shewn. The pipes 16 are provided with numerous perforations, and in
the plates D are formed orifices covered by flap doors, through which the
pipes 16 pass.
I will now proceed to describe the manner in which my Invention is
operated, referring first to the distillation of shale, and secondly to the
production of illuminating gas.
The gas retorts 8, Figure 2, are fired from below in the ordinary
manner from the grates 17, from whence the products of combustion
pass through ports 18 into an upper chamber 19 containing the retorts 8,
around which they circulate. The said products of combustion after
heating the retorts escape through the ports 20 into the flue 21, by
which they are conducted to the other side of the brick setting, and
thence through ports 27 into the chamber 22 containing the retorts A, B,
and C, which are thus heated, the waste products of combustion being
thereafter conducted by the flues 23 to the stalk or vent 24.
In order to prevent waste of heat and to increase the temperature in
the chamber 22, dampers 25 are or may be introduced into the flues 23,
which may be closed or partially closed, the supply of air to the furnace
being maintained by means of a fan 26 or by other suitable blowing
apparatus, from which the air is blown into the furnace through nozzles
placed beneath the bars.
The gas evolved from the material in the retorts 8 is led through the
breech pipes 9 and hydraulic main 10, through the pipes 11, into the tar
chest 12, from whence it passes through the pipe 4 to the gas holder 14
and pipe 13, and thence through the cocks 15 to the pipes 16, whcreat
it is ignited upon issuing through the numerous perforations with which
the pipes 16 are pierced. The gas holder 14 is provided in order to give
a due degree of pressure to the gas in the pipes 16. The retorts A, B,
and C are thus heated by the combined agency of the products of com-
bustion from the furnaces 17, and the ignition of the gas evolved in the
retorts 8, and also, as herein-after set forth, by the combustion of the
non-condensible gases evolved in the retorts A, B, and C, themselves.
from the shale under treatment.

page_text: feeds T, and is slowly traversed by the action of the portions of screw
thread F to the other end of the retorts. In its passage the shale is
repeatedly turned over, agitated, or stirred by the flat blades or stirrers G,.
whereby fresh portions of the shale are continually presented to the hot
side of the retort, and the gases evolved are more effectually driven off,
the portions of screw thread F being perforated, as shewn at Figure 2,
so as to allow of the free passage of the gases to the eflux pipes or
passages t. The spent charge of shale on arriving at the discharge end
of the retort falls down through the ports or passages Z into the hori
zontal cylinder g, along which it is passed and out of which it is
discharged by the action of the screw h, the inclined cylinder q being
provided and attached to the cylinder g in order to "seal" and prevent
the escape of the gases along with the spent charge; or the same object
may be effected by causing the end of the cylinder g to dip downwards
into a water trough.
The gases evolved from the shale thus passed through the retorts pass
to the valve chests u, and after parting with a portion of their impurities
in the shape of tar, which drops into the tar chest v, rise to the main wo,
and thereafter to the condenser tubes y, where they are condensed in the
usual manner and converted into shale oil, which falls back into the tar
chest v. The condenser tubes y are also provided with the ordinary oil
and water separators, but which are not shewn on the Drawings. The
non-condensible gases are drawn off from the upper condenser tube
through the pipe z by the gas exhaust apparatus I, and are thereafter
forced through the pipe 3 into the pipe 4, wherein the said uncon-
densible gases become incorporated with the gas passing through the
said pipe 4 from the gas retorts 8, as herein-before described.
L
In manufacturing illuminating gas according to my Invention the
process is nearly similar to that already described with reference to the
production of shale oil. Shale coal or other gas-producing material is
charged into the retorts A, B, and C, and the gas evolved therefrom is
conducted through the eflux pipes main and exhaust apparatus, but
instead of being allowed to enter the pipe 4, being still an imperfect gas,
the two-way cock 5 is turned so as to shut off communication therewith
and divert the gas into the pipe 6, from whence it is led by the
branches 7 into the gas retorts 8, where it is superlicated by the higher

page_text: .
Bell's Improvements in Distilling Coal Shale, &c.
temperature of the retorts 8, after which process of superheating it
passes off through the breech pipes 9 and hydraulic main 10 to the tar
chest 12, and from thence through the pipe 4 to condensers, and therc-
after to the gas-holder provided for the reception of the permanent gas
so produced. A portion of the illuminating gas thus manufactured may
be employed to assist in heating the retorts, as hercin-before described
and shewn.
It is to be understood that in place of using green coal or fuel in the
fire-grates 17, the hot coke drawn from the retorts 8 may be discharged
on to the fire-grates, as is well understood.
Having now described and particularly ascertained the nature of my
said Invention, and the system, mode, or manner in or under which the
same is or may be used or practically carried into effect, I would
observe in conclusion that what. I consider to be novel and original, and
therefore claim as the Invention secured to me by the herein-before in
part recited Letters Patent is,-
First. The general arrangement and combination of apparatus con-
stituting the mechanical system for the purpose of carrying out the
objects of this Invention, substantially as hercin-before described and
shewn.
Second. The tubular retorts, placed horizontally or at an angle, and
which are provided with an interior revolving shaft, on which are fixed a
screw thread or portions of a screw thread, and also blades or stirrers
placed at intervals, by the combined action of which the charge is
advanced and repeatedly turned over or stirred in its progress through
the retort, as herein-before described and shewn.
Third. The " screw creeper” or “travers" for carrying off the spent
charge, as hercin-before described and shewn.
Fourth. The arrangement and construction of mechanical feed for the
purpose of supplying the charge to the retort, as more especially shewn
at T, Figure 3 of the appended Sheet of Drawings.
Fifth. The system of distilling shale or coal in retorts by means of gas
produced in one or more other retorts which are heated by fuel, the
combustion of which is effected either by draught, or (when dampers are

page_text: introduced into the exit flues) by any suitable blowing apparatus, as
herein-before described.
In witness whereof, I, the said John Bell, have hereunto set my
hand and seal, this Twenty-first day of November, One thousand
eight hundred and seventy-four.
JOHN. BELL. (L.S.)