IMPROVEMENTS IN THE DESTRUCTIVE DISTILLATION OF COAL AND SHALE FOR THE PRODUCTION OF ILLUMINATING GAS, FUEL, AND OIL, AND OTHER 99 PROVISIONAL SPECIFICATION
Year: 1873

page_text: LETTERS PATENT to John Patison, of Airdrie, in the County of
Lanark, North Britain, Manufacturing Chemist, for the Invention
of "IMPROVEMENTS IN THE DESTRUCTIVE DISTILLATION OF COAL AND SHALE
FOR THE PRODUCTION OF ILLUMINATING GAS, FUEL, AND OIL, AND OTHER
99
PROVISIONAL SPECIFICATION left by the said John Patison at the
Office of the Commissioners of Patents, with his Petition, on the
15th February 1873.
I, JOHN PATISON, of Airdrie, in the County of Lanark, North Britain,
Manufacturing Chemist, do hereby declare the nature of the said In-
vention for "IMPROVEMENTS IN THE DESTRUCTIVE DISTILLATION OF COAL AND
SHALE FOR THE PRODUCTION OF ILLUMINATING GAS, FUEL, AND OIL, AND OTHER'
PRODUCTS THEREFROM, AND IN THE APPARATUS THEREFOR," to be as follows, that
is to say :-
•
The improvements of my said Invention consist generally in sub-
mitting coal and shole
a mixture of these, with other organic.

page_text: -
compounds to destructive distillation in the manner hercin-after
described, and in treating the hydrocarbons so obtained, or that may
have been obtained from other sources, in such a manner with the
carbonaceous residuum of the said coal and shale as thereby to produce
illuminating gas, fuel, oil, gas-producing substances, and other products.
The desired maximum amount or quality of one or other of these
products being attained by the regulation of the temperature, and also
by admitting hydrocarbons during the actual process of distillation,
whether these hydrocarbons may have been produced in the new manner
herein-after specified, or may have. been derived from other sources,-
and in proceeding first to obtain these products, and extract and expel
the volatile matters from the coal or shale, whether these may be
employed by themselves or along with other substances, I use cast-iron
cylinders varying in diameter from about eighteen inches to three feet,
and in length from eighteen feet to thirty feet, more or less, whether in one
casting or more, bolted or united together in any way. The said retorts
or cylinders are fitted with a shaft or shafts revolving inside and running
parallel with said cylinders or retorts, and placed in or on the said shaft
or shafts, radial screw blades attached thereto, either cast on the same in
the form of one casting, or separate screw blades bolted to the shaft or
shafts so as to form one continuous screw. Near the inlet opening of
these cylinders or retorts I have that portion of the screw which receives
and screws or draws in the material to be distilled, fitted with cast-iron
teeth which are placed somewhat at an angle from the bevel of the
screw itself. A bead or contracted neck is also cast at the mouth of
these retorts or cylinders so as slightly to contract it, and cause the
material to be more effectually seized and crushed at the entrance, and
so facilitate its passage afterwards forward and down the retorts or
cylinders, and through the same; and should the materials to be operated
on in certain states require a vertical screw passing downwards through
the hopper after-mentioned to feed the aforesaid screws running parallel,
this may also be supplied or added, and I allow a little space between
the screw blades and the sides and tops of the said cylinders or retorts so
as to afford space for the free egress or escape of the gases, vapours, or
other products into the condensors, as herein-after specified, and where
the shaft or shafts enter the said cylinders or retorts a convenient round
opening is cast on the end next to the gearing connected with the motive
power, fitted with a stuffing box, with the packing screwed tight to
prevent any escape of the products, and I connect to the said retorts or

page_text: cylinders suitable condensing or cooling pipes or apparatus, whether by
means of one large or several smaller outlets, by which the oil and
liquids generated are condensed, which products are preferred to be
treated in the manner after specified. I apply the heat to the exterior
of these retorts or cylinders, or introduce superheated steam or heated
gases or other medium inside for heating the same in any ordinary
manner; and I prefer to place these cylinders or retorts considerably
higher at one end than at the other, and then conduct the heat to the
highest point so as to distil the same (off or over) by destructive dis-
tillation; and upon the distillation commencing, the before-mentioned
shaft or shafts (with the screw blades attached thereto) are turned or
put in motion by a steam engine or other motive power, and at this
stage of the process other gases or liquids or hydrocarbons may be
introduced so as to improve or increase the quality of the hydrocarbons
then being produced whether in a gaseous or liquid, form. I enclose
the shale or coal, or mixture of these, with other organic substances by
means of a hopper or opening at one end of these cylinders or retorts, by
preference that part of the same which is placed highest, which hopper
or funnel, made by preference of malleable iron, is fitted at the top,
having a stopper adjusted so as to admit the material to be distilled
inside, and having a handle with a weight attached on one end so as to
shut the stopper on the operator removing his hand, and keep the same
shut till charging again. And the shaft or shafts having the screw
blades attached thereto, before mentioned, may be so arranged as to
run close one with the other, so as to keep the materials loose and open
to free the gases, or they may work singly by their rotatory or revolving
motion screw, and carry the material forward to the low end of the
retorts or cylinders; and while this is being done the distillation is going
on and thereby greatly facilitated, all affording an effectual means of
carrying on the distillation in a continuous and regular method. At the
lowest end of these cylinders or retorts an opening or outlet pipe is
placed for the discharge of the residuum (which might be previously or
subsequently treated as herein-after mentioned) into water, or into close
vessels or otherwise, to be used as fuel for heating purposes, or as after
described for distilling the said coal or shale.

page_text: obtaining the greatest amount of liquid hydrocarbon compounds to be
used up in the process after mentioned, the heat, by whatever mode
it is applied or introduced, is kept at as low a temperature as possible to
effectually exhaust the materials operated upon, but on the other hand
when the distillation is carried on mainly or entirely for the purpose of
obtaining the greatest amount of permanent or illuminating gas, leaving
the residuum free of volatile matters for the manufacture of blacking, or
otherwise as after mentioned, I then prefer to raise the heat to a much
greater extent, and if preferred in this case, to use cylinders or retorts
made of fire-clay or other compound fitted to resist a great heat, and I
also prefer to lead the said vapours or gases so generated through any
highly heated material, whether this be composed of heated brick, coke,
scrap iron, or otherwise enclosed in metal or other heated chambers, and
I may also add other gases or vapours so as to blend or mix the same
therewith, the object being to decompose the greatest amount of the
hydrocarbon vapours so generated, and thus increase, cheapen, or improve
the same, when so eliminated into permanent gas.
Having now described the new mode I adopt to carry out the first
part of my said Invention, consisting as before mentioned in submitting
the coal and shale, or a mixture of these by themselves, or mixed along
with other organic compounds or substances, and facilitating the
distillation of these by the aid of a revolving shaft or shafts with screw
blades, for the purpose of forming the products specified, as aforosaid.
I now proceed to describe how I make use of and treat the hydro-
carbon oils and other liquids (obtained by the first-mentioned process or
treatment), and first, as to the nitrogeneous liquors, I prefer to neutralise
the same with acids to form salts on evaporation in the usual way;
and secondly, as to the hydrocarbon compounds or oils, these may be
distilled in any usual suitable way, but the mode I adopt is to pump the
same in a slightly heated state at a temperature varying from 80 to 90
degrees Fahrenheit into a suitable elevated tank, so as to run by
gravitation into the retorts or cylinders aforesaid, and hydrocarbons
obtained from other sources may also be used, treated, and mixed
therewith. The heated oils from the tank are conducted through
suitable sized pipes leading to and controlled by cocks at the lower part
of the retorts or cylinders, determined by their size and position, all so
as to be heated and dissolved by the residuum of coal or shale, either by
themselves or along with other organic matter supposed to be partially

page_text: or wholly spent or exhausted by the aforesaid destructive distillation
process, while the said residuum is in a highly heated state. The effect
of this inlet or supply of hydrocarbons is to create a second distillation,
especially of the lighter portion of these hydrocarbons, and so far
incorporate the heavy part thereof with the aforesaid residuum of coal
or shale, while the lighter oils so produced and condensed may again be
further treated and purified with acids and alkalics in the usual manner.
The residuum of coal and shale or other organic substances may thus be
utilized by the process now described, and thus made available for the
purposes herein-before and to be herein-after described, while according
to the temperature of these cylinders or retorts maintained for the
products desired, as before mentioned, the distillation is carried on, and
the whole fixed carbon and gas producing fuel or charcoal (which may
be ground for blacking or used for other purposes) are all thus regularly,
systematically, and continuously carried forward to the discharge pipe
at the lower end of the retorts or cylinders and discharged, all as before
stated. The admission of hydrocarbon into the partially or wholly
spent, exhausted, or distilled residuum of said coal or shale or other
organic substance, all in the manner herein-before described, for
producing or forming a second or double distillation, may also be carried
on in, the ordinary shaped retorts or cylinders without the aid of a
rotatory screw, and the said residuum so treated may afterwards be
either used by itself or ground along with other organic substances, for
the purpose of producing a material for making illuminating gas, oil.
or wholly spent or exhausted by the aforesaid destructive distillation
process, while the said residuum is in a highly heated state. The effect
of this inlet or supply of hydrocarbons is to create a second distillation,
especially of the lighter portion of these hydrocarbons, and so far
incorporate the heavy part thereof with the aforesaid residuum of coal
or shale, while the lighter oils so produced and condensed may again be
further treated and purified with acids and alkalies in the usual manner.
The residuum of coal and shale or other organic substances may thus be
utilized by the process now described, and thus made available for the
purposes herein-before and to be herein-after described, while according
to the temperature of these cylinders or retorts maintained for the
products desired, as before mentioned, the distillation is carried on, and
the whole fixed carbon and gas producing fuel or charcoal (which may
be ground for blacking or used for other purposes) are all thus regularly,
systematically, and continuously carried forward to the discharge pipe
at the lower end of the retorts or cylinders and discharged, all as before
stated. The admission of hydrocarbon into the partially or wholly
spent, exhausted, or distilled residuum of said coal or shale or other
organic substance, all in the manner herein-before described, for
producing or forming a second or double distillation, may also be carried
on in, the ordinary shaped retorts or cylinders without the aid of a
rotatory screw, and the said residuum so treated may afterwards be
either used by itself or ground along with other organic substances, for
the purpose of producing a material for making illuminating gas, oil.
or fuel.
I shall now proceed to detail more particularly the effect of the
temperature used in the said improved mode and means or manner of
distillation, so as to secure the various products that may be wanted;.
thus, first, when the whole of the volatile or heavy oils are wished to be
expelled for the purpose of gaining the greatest amount of permanent
gas, and the residuum fit to be ground into moulders' blacking, or
charcoal, or otherwise, then the temperature is greatly increased; second,
if the lighter portion of these hydrocarbon oils are wanted, whether crude
or for the purpose of being further refined, and the residuum to be
discharged for the purpose of fuel or portable or ordinary gas-producing
material, the temperature is considerably lowered, and the vapours of
the oils so eliminated or discharged may be condensed, and the cooling
apparatus thereof so arranged by having different exit pipes at various

page_text: lengths of the cooling apparatus so as to collect or run off separately
and by themselves the lighter or heavier oils, as the case may be; and
third, in case the residuum thereof may be too heavily incorporated or
charged with liquid hydrocarbons a discharge stop-cock may be placed
in any suitable part of the said retorts or cylinders, for the purpose of
letting off any surplus or excess of liquid hydrocarbons from the said
residuum, fuel, or gas-producing material while in a heated state, and
this surplus or excess of liquid hydrocarbons may be returned to any
suitable vessel to be again used in the same way.
:
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Patison in the Great Seal Patent Office on
the 1st August 1873.
:
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
PATISON, of Airdrie, in the County of Lanark, North Britain, Manu-
facturing Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifteenth day of February, in the year
of our Lord One thousand eight hundred and seventy-three, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said John Patison, Her special licence that I,
the said John Patison, my executors, administrators, and assigns, or
such others as I, the said John Patison, my executors, administrators,
and assigns, should at any time agree with, and no others, from 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 AND SHALE FOR THE PRODUCTION OF ILLUMINATING GAs,
FUEL, AND OIL, AND OTHER PRODUCTS THEREFROM, AND IN THE APPARATUS THEREFOR,”
upon the condition (amongst others) that I, the said John Patison, my :
executors or administrators, by an instrument in writing under my,
or their, or one of their hands and seals, 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

page_text: Great Seal Patent Office within six calendar months next and imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John Patison, 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 in writing, reference being had to the several
explanatory figures and reference letters on the Sheet of Drawings
which I have hereunto appended for the purpose of showing the nature
of my said Invention, and the best modes and means I am at present
aware of for performing or carrying the same into effect or practice, the
same reference letters indicating the same or equivalent parts in all the
Figures, that is to say :—
The improvements of my said Invention consist generally in sub-
mitting coal and shale or a mixture of these with other organic
compounds, to destructive distillation in the manner herein-after
described, and in treating the hydrocarbons so obtained or that may
have been obtained from other sources in such a manner with the car-
bonaceous residuum of the said coal and shale, or the residuum of wood,
peat, or other organic substances, as thereby to produce illuminating
gas, fuel, oil, gas producing substances, and other products.. The desired
maximum amount or quality of one or other of these products being
obtained by the regulation of the temperature, and also by admitting
bydrocarbons during the actual process of distillation, whether these
hydrocarbons may have been produced in the new manner herein-after
3 specified, or may have been derived from other sources, and in proceeding.
first to obtain these products, and extract and expel the volatile matters
from the coal or shale, whether these may be employed by themselves or
along with other organic substances, as hercin-before stated, in a new or
improved construction and arrangement of the parts of cast-iron cylinders
or retorts and their fittings, all as follows:-
Figures 1 to 4 on the Sheet of Drawings represent various views of
one modification (or construction and arrangement of the parts) of a set
of two of my said improved retorts and their fittings, all constructed in
accordance with and for the purpose of carrying out or performing my
said Invention. Figure 1 is a longitudinal vertical section taken on the
line 1 1 in Figure 2, through the centre of the first retort A of the
set, with its conducting pipes J, J, condenser K, and receivers L, i,

page_text: attached an complete; and Figure 2 is a corresponding section of the
second retort A¹, taken on the section line 2 2 in Figure 3, which is
a front end clevation of both retorts A, A³, and the brickwork a, showing
the duplex screw shaft 6" and screw wheels b, for working the conducting
screws B, B¹, within the retorts; while Figure 4 is a detached plan of
the condenser K and its oil receivers L, i, i, i¹¹, corresponding to Figure 1,
which is not shown or seen in either Figure 2 or Figure 3.
Referring to the construction and arrangement of the retorts, and the
apparatus or appliances fitted thereto, A, A², are the two cast-iron retorts
preferably made nearly cylindrical, of from about eighteen inches to
three feet in diameter, and from eighteen feet to thirty feet in length,
formed in two or more pieces in their lengths, bolted together as at A",
with close removable ends A¹¹¹, A¹¹¹¹, screwed or otherwise secured tightly
thereto; but these retorts A, A¹, may also be made of an oval shape, and
preferably in either case slightly tapered longitudinally, widest, as shown,
towards the discharge end A¹, and built in their brickwork a in a set
of two, laid at an angle or inclined lowest at the said widest and discharge
end A, but they might be built singly, or in sets of three or more, and
at other angles more towards the vertical or the horizontal plane, cach
within an annular or other shaped close heating flue a' surrounding it,
with a heating hearth a¹¹ or furnace a¹¹¹ below, fed from doors, fitted
preferably at the sides of the brickwork a, and with a duct a' leading
therefrom into the lower end of the flue heating chamber a¹. Within
each retort A, A¹, a conducting screw is fitted, preferably of cast iron,
with a continuous hollow thread B¹ on the hollow shaft B, so as to have a
small current of steam or water passed through it to keep it sufficiently
cool that it will withstand the great and destructive heat of the retort.
The journals B" revolve in bearings in the end covers A", A¹¹, the
one A¹¹¹ being formed with a fluid tight stuffing box, packed with asbestos
or other suitable packing, where the ends B" of the shafts B, B, pass
out of the retorts to be actuated by the screw wheel bon each, by the
duplex screws or worms 6¹ on the motive shaft 6", seen in Figure 3,
actuated by any adjacent motive power shaft or engine at a slow speed,
so that when these b, b¹, b¹¹, and the screws B, B', arc turned, as indicated
by the black arrows on them, the screw threads B', which are preferably :
of an increasing pitch and proportionally larger in diameter, both towards
the bottom of the retort, so as to be nearly parallel to its sides, and slack
enough at the lower bearing A"", rest on, and thus loosen and carry

page_text: forward the coal and shale (or other organic oil or illuminating gas
producing material, as peat, or residuum, or waste wood, and the hydro-
carbons hercin-before stated, or mixtures of any of these), indicated at C,
through the retorts A, A', after it is fed into the hoppers D in suitable
charges through its bottom opening and valve seat D¹, closed by the
valve Du, controlled and actuated by the connecting link D³ and hand
lever D, fulcrummed and balance weighted to automatically close itself,
after being raised to let cach charge into the intermediate close feeding
chamber E, leading and conducting the said materials O so charged into
it, into the upper part A³ of the retorts, where one of the small pitch
feeding-in threads B' is formed or fitted with teeth B³, set at such an
angle in relation to the thread of the screw itself that they will draw
in, cut, and force or screw the material fcd in, through, or past the
contracted neck or collar A³, cast or fitted near the mouth or throat E',
to cause the material C to be more effectually seized, compressed, and
crushed at this part, and so be more casily carried or conducted therefrom
by the after part of the screw B¹ towards and into the outlet or discharge
opening and conical pipe F, F", near the lower end of the retorts A¹, A'.
This discharge pipe or conduit F¹, shown on the first retort A, Figure 1,
is made so short as to open some distance above the heating hearth a",
and allow the hot discharged residuum or cinder C¹ to be spread out
over the heating hearth, so that it may be completely burned thereon,
either by itself or in conjunction with the assistant fuel and furnace
at a¹¹¹, so as to utilize all the heat and solid carbon which may be in the
said residuum to heat the retort, as indicated by the red arrows in the
heating chamber a¹, a', while the unutilized heated products of combus-
tion pass off to the chimney z at the upper end of the retorts and their
heating chambers a³, common to both in the centre, but it might be a
chimney to cach chamber. The waste solid residuum C", when reduced.
to a useless ash, is finally removed by the discharge screw G (or other
cquivalent appliance), fitted and actuated within a recess G¹ in the
hearth a³ continuously or at intervals, by motive power or by hand, into
an ash-pit or removing trucks for the purpose. When the residuary
products of distillation, or solid carbon, or cinder C₁, discharged into the
outlet conical pipe or duct F¹, are not suitable for or desired to be used
to heat the retort, and desired to be cooled and used for other purposes,
such as for making a gas or oil producing fuel mixed with crude or
refuse oils or other organic substances, or for making burning coke, or
heating fuel, or ground carbon or blacking, then this pipe F¹ is made

page_text: close, as fitted in the arrangement of the second retort A³, shown in
Figure 2, where it is continued down so that its lower mouth F¹¹ opens
and conducts the residuum C³ only into the cistern of water H, fitted
into the building a, a³, below, where the ash hearth is in Figure 1, so
that the residuum C¹ is there cooled and drawn, or discharged out of the
water by the inclined screw G, worked in a conduit F for the purpose,
on to the ground or into removing trucks, as may be desired; or other-
wise the water cistern H may be dispensed with, and the residuum or
cinder C¹ discharged out of the close discharge pipe F or duct F¹ into
close vessels to cool without exposure to the air, in either case ready for
being subsequently used for the purposes described.
Another improvement in connection with these retorts when the
threads B¹ of the conductiug screws B, B¹, are continuous consists in.
fitting a single or double thin steel or iron-bladed scraper I at one end
of the retorts A, A³, clear of the extreme end of the thread B¹, having a
long parallel rod or handle I' secured to it, working out through a small
stuffing box I" of the end cover, as shown at A; all so that when
the handle I' is pushed forward a certain regulated distance, and the
screw B¹ is turned in the reverse direction to that of the black arrows on
it, the scraper I takes on to and embraces the first thread of this
screw B³, as indicated at B³ in Figures 1 and 2, so as automatically to
scrape and clean both sides or surfaces of the thread B' at the same
time while drawing in the scraper up towards the front or narrow
end A or one side and surface in this way, and the other side and
surface during the return stroke while reversing the screw to return the
scraper to its normal or stationary position again.
Although the threads B₁ of the conducting screws B, B¹, of the
retorts A, A¹ are shown and described as cast hollow and continuous, yet
it is to be understood that they might also be made solid, or solid and in
sections or parts of screws, as the blades for the screw propellers of
ships, and for the agitating and compressing screw spindles of pug
and other mills. These sections or blades of screws being made of cast
or malleable iron, or of steel, and bolted or screwed by spindles or
flanges to their shafts B which are either made hollow or solid, as
preferred, and when hollow the steam and water could be let into the
upper ends by a small stationary pipe c fitted with a stuffing box, and a
somewhat similar tube or hole c¹ may be fitted or made at the lower end

page_text: of the shaft for an outlet to the fluid admitted, each of these inlet and
outlet orifices being controlled by a regulating cock or valve.
Although each retort A, A¹, is shown as only fitted with a single
feeding screw B, B¹, actuated by screws and screw wheels, it will be
understood that two or more screws might be used, laid nearly parallel
to each other, and made in two lengths when preferred for long retorts,
worked on the outside of one or both end covers A", A"", either by
screw gearing or by slow moving toothed, bevel, or spur wheel gearing;
and it will also be evident that other forms of heating furnaces a" and
hearths a¹¹ might be used with their feeding doors at the ends instead of
at the sides, whilst the residuum C' might be removed by the screws G,
or other equivalent, laterally to each side when preferred. A little space
is left between the screw B, B', and the inside surfaces and tops of the
retorts A, A¹, so as to leave room for the free action of the cleaning gear
or scraper I, I¹, before described, and afford space for the free egress or
escape of the gases, vapours, or other products into one or more main
conducting pipes J, J, and through any ordinary condenser K or other
equivalent arrangement of conveying pipes or apparatus fitted to each
retort A and A¹, all as indicated by the blue arrows on these conduits,
whether these said gases, oils, and liquids so generated are condensed and
by means of one large duct K' or the several smaller outlets k, k¹³, k¹¹,
the condensed products are preferred to be run off according to their
specific gravity into the respective receivers K" or i, i, ¹, the heaviest
oils in i, the secondary quality in ", and the light burning oil and spirit
in, whilst the uncondensed gases, residuary oils, ammoniacal liquids,
and water pass on to the outlet pipe K³, into the large receiver K“, all
treated in the manner stated and to be hercin-after more fully specified.
The mode of procedure is as follows:-The material C to be distilled
is fed into the vessel E in charges at intervals, regularly to keep the
screw B and retort constantly working and distilling, while the heat is
applied to the exterior of the retorts A, A', as described, for producing
illuminating gas at low temperatures about the dull red heat, or for
producing oils and paraffine at temperatures at and below that, or if
preferred for adjusting the temperatures more equally at this lower heat
these cylinders or retorts A, A¹, may be surrounded with an iron steam
casing or jacket, into which I introduce superheated steam or heated
gases, or other medium for heating the same in any ordinary manner,

page_text: and have the distillation carried on in partial vacuum by means of an
ordinary exhausting and forcing pump or other equivalent, such as a jet
of live steam from a boiler introduced by a pipe and cock j,j, to
the throat of the conducting pipe J to draw and force the gases
from the retort through the condensers K. The angular position of
the retorts A, A', (as I prefer to place them) assists in conducting the
heating fluids to the highest point or end a* where they escape into the
chimney z, controlled by a damper, all so as to distil the products (off
and over), through the pipes J, J, and condenser K, by destructive
distillation or otherwise. Instead of the waste heating gases from the
top of the heating chamber a and the retorts A, A¹, passing off into
the chimney they may be conducted into the heating flues of a steam
boiler or other equivalent to be thus utilized in driving the motive power
engine for the feeding screws. Upon the distillation thus commencing,
the before-mentioned screw shaft or shafts B, B¹, are turned or
actuated by their motive gearing as before described to free the gases
cvolved and carry the material forward to the lowest discharge end of
the retorts. When at this stage of the process other gases or liquids or
hydrocarbons may be introduced or supplied to the retorts A or A¹, as
by the pipes m controlled by the cock m³, from the supply cistern M
above, so as to improve or increase the quantity and quality of the
hydrocarbons then being produced, whether in a gaseous or liquid form.
While all this is being done the distillation is constantly going on and
thereby greatly facilitated, all affording an effectual means of carrying on
the distillation in a continuous and regular method.
When it is desired at intervals to clean the screws or screw blades B'
I stop filling in the material to be distilled at the hopper D for a time to
allow of the retorts being emptied by the material therein being all or
nearly all screwed out or discharged, when I then push into gear the
scraper, groove, arm, or cleaner I, I', either by the hand or by motive
power, and allow the screw or screw blades, when these are again put in
motion, to scize the same, and run it up to the end of the screw, when
I then reverse the motion of the axle upon which the screw or screw
blades are fixed, which causes the said arm, groove, or cleaner I to
travel back again. This may be repeated several times until the screw
or screw blades B¹ are thoroughly cleaned, when I draw this groove,
arm, or cleaner out of gear with the thread at the lower end of the
screw, and then proceed with the distillation as before. The illumi-

page_text: nating gas thus generated during the said process of destructive
distillation at the temperatures at or about the low red heat may be
treated and used for lighting or heating purposes in the usual way; but
it is hereby specially provided that when the distillation is carried on
for the purpose of obtaining the greatest amount of liquid hydrocarbon
compounds to be used up in the process after mentioned the heat by
whatever modo it is applied or introduced is kept at as low a temperature
as possible to effectually exhaust the material operated upon.. When I
thus wish the distillation to be carried on for the production of the
liquid hydrocarbons, and for making use of the spent residuum C¹, and
rendering the same available as fuel by itself, or in connection with the
permanent gas from the pipe K, as a heating agent for carrying on the
said distillation, or in conjunction with other fuel employed as an
auxiliary in the heating chamber a¹¹, a¹¹, Figure 1, which chamber or
chambers are preferably placed near the outlet or discharge opening F, F',
of the said retorts, and the residuum after being discharged by the screw
or screw blades B¹ is allowed to fall or drop into the said heating
chamber or hearth a" placed below and at the side of the discharge or
outlet pipe F¹ from the cylinders, the said residuum after being discharged
by the screws B, B', is allowed to burn in a considerable mass at once on
the said hearth at C¹, a", atmospheric air being freely admitted at the
side and near the bottom by means of port holes or furnace bars placed
on the bottom, and the heat is afterwards conducted through the
flues a³, a¹, or heating chamber around the said retort A, and these
heating chambers and the flues round the retorts are preferred to bo
lined with brickwork. The unconsumed refuse ash C" is discharged, as
before stated, out of the hollow hearth G¹ by the screw G or otherwise into
an open pit or into wheelbarrows to be utilized or employed for making
fire-bricks or other articles of use, or it may be ground and saturated with
the ammoniacal liquor (one of the products of the said distillation), and
rendered available for manure. The vapours and gases from the dis-
tillation are conducted through suitable condensers K provided with
various air-tight openings k, k', k", and receivers i, i, i, so that the
different specific gravities of oils may be collected separately as they
travel, and are condensed in the cooling pipes K, and the uncondensable
gas produced in the retorts A', Figure 2, after leaving its condensers and
coolers is conveyed by its own pressure into near the centre of the
retort A, Figure 1, through the pipe K¹ by the pipe controlled by a
tap 1, all as indicated by the arrows in these pipes, or this may be assisted

page_text: by means of an exhaust jet of steam or other equivalent introduced
through the pipe j in addition to its own pressure, as before described.
That portion of the said gases which escapes combustion with the
carburetted hydrogen vapours, then forming as they are presented in
the nascent state, is conveyed along with the whole vapours and gases
of the retort A, Figure 1, through its condensing pipes J, J, and
coolers K, K, and the whole or a portion of the permanent gas passed
through the condenser from the pipe K¹, finally escapes in the usual
manner through the pipe n, or is led by the pipe o (both controlled by cocks
or valves¸n and o¹) into a pocket O, on the discharge mouth-piece F
so as to pass through it in jets into the discharged cinder O¹, where it is
consumed, near the bottom of the said discharge or outlet pipe F¹
leading from the retort, Figure 1, which thereby assists in the deoxi-.
dation of the atmospheric air, and in the keeping up of the heat of the
retorts; and to further regulate this dampers or valves may be fitted on
the doors or port holes for admitting the air to the said heating chamber
or hearth a", a¹, and to keep up the heat during a temporary stoppage,
these dampers or valves may be closed, as well as those of the main
flues a¹ leading from the top of the heating chamber. When the dis-
tillation is carried on mainly or entirely for the purpose of obtaining the
greatest amount of permanent or illuminating gas, leaving the residuum
free of volatile matters for the manufacture of blacking or otherwise,
as will be herein-after mentioned, I prefer to raise the heat of the
retort to a much greater extent, and after the carburetted hydrogen
gases or vapours, generated in the way before specified, leave the retorts
or cylinders, I conduct the same direct from the pipe J through any
highly heated ordinary illuminating gas producing retort and material
in it, whether this be composed of heated brick, coke, scrap iron, or
other equivalent; these fire-clay or other enclosed chambers or retorts
are by preference placed nearest the heating chambers a", a, at the
sides, so that the waste heat from the fires and heating flues of these
hot gas retorts may
be led into the heating chambers a", a", of the
screw retorts or cylinders A, A, before described, Figures 1 and 2, so as
to work or distil the materials in these with the spent heat from the same
with or without the use of the heating chambers a", and an auxiliary
furnace a, at the heating chamber a" as required; and during the
actual process of the said destructive distillation, I admit hydro-
carbon liquids either cold or heated in a small stream regulated by

page_text: suitable pipes and stop-cocks m, m², as before specified; but when used
hot these hydrocarbon liquids are heated on their passage to the retorts
or cylinders A, A', and changed into hydrocarbon vapours, which are
introduced into the coal and shale, or a mixture of these with other
organic substances, as peat, waste wood, or sawdust, at a point by pre-
ference midway from either end of the said ordinary highly heated retort.
These gases thus produced in this improved manner in both retorts are
finally conducted from the highly heated retort or retorts, through
any ordinary arrangement of illuminating gas condensers and purifiers,
and then used for illuminating or heating purposes in the usual way. The
tarry products which escape decomposition in the said process may
again be returned, as by the pipes q and pump q' to any suitable vessel
as M, and admitted by the pipes m, m³, as before mentioned, into the
same retort or cylinder A, A', or if such tarry compounds be too thick
a portion of thinner hydrocarbon oils may be advantageously mixed
therewith, as crude or heavy oils derived from other sources; but thicse
mixing hydrocarbon oils are preferably taken from the crude or first run
state from the vessel i, made at a low heat in the manner before
specified from the retorts A, A, Figures 1 and 2, either by itself or
mixed with the tarry products given off by this new Invention in gas
making, by which means or process the whole of the tarry compounds
(by products of the gas manufacture) may be utilized and converted
into illuminating gas. The residuum as C is withdrawn from the retorts
or cylinders A, A, in this process in the same manner as described in
reference to the retort A', in Figure 2, and can be either used as fuel, as
the case may be (according to the nature of the material used) as
desired in close vessels and ground for moulders' blacking; and this
said residuum C¹, Figure 2, produced by the before-mentioned process of
destructive distillation may itself be used as a portable illuminating gas
producing fuel; or this residuum C¹ may be taken and mixed with coal
or other organic substance, such as cheap dross and triping coal, or
peat, chip waste wood, bark and sawdust, in proportions of from five to
fifteen hundredweight of the said residuum C¹ to one ton of the whole
mixture with the coal or other organic substances, all for the purpose of
producing a portable illuminating gas producing fuel.
Having now described the new mode I adopt to carry out the first
part of my said Invention consisting as before-mentioned, in submitting
the coal and shale, or a mixture of these by themselves, or either, or

page_text: both of these, with other organic substances or compounds, as peat and
refuse wood and sawdust, and in facilitating the continuous distillation
of these, cither by the aid of a revolving shaft or shafts with screws or
screw blades for the purpose of forming the products specified aforesaid.
I now proceed to describe how I make use of and treat oils not
intended for the manufacture of gas and nitrogeneous liquids (obtained
by the first mentioned process or treatment), and first, as to the
nitrogeneous liquids, I either neutralize the same with acids to form
salts on evaporation in the usual way, or mix and incorporate the same
with the spent ash C" coming from the residuum C³, Figure 1, as
before stated, to form artificial manure; and secondly, as to the hydro-
carbon compounds intended for lubricating or burning oils; these, which
are obtained from the respective receivers i, i¹, and ¹¹, as before stated,
may be distilled in any usual suitable way, but the mode I adopt is to
pump the same in a slightly heated state at a temperature varying from
eighty to ninety degrees (80° to 90°) Twaddle into a suitable elevated tank
(as M), so as to run by gravitation into the retorts or cylinders A, A¹, be-
fore stated; and hydrocarbons obtained from other sources and by ordinary
modes of distillation may also be used, treated, and mixed therewith
as these. The heated oils from the tank are conducted through suitable
raised pipes (as m) leading to the retorts, and controlled by cocks (as m¹)
determined by their size and position, the inlet of which may be regulated
in any suitable way; but the mode I prefer is to have a vessel con-
taining the hydrocarbons on an elevated situation, and have the flow
from these into a smaller cistern regulated by a suitable stop-cock or
throttle valve connected to a lever, float, or hollow ball, floating in the
liquid of the lower small tank, and so connected to the same as to be
self acting and capable of keeping the hydrocarbons therein at nearly
the same level, while the flow therefrom is regulated to the uniform
supply desired by another stop-cock having an indexed guage, all so as
to be heated and re-distilled by the residuum of coal and shale, either
by themselves or along with other organic matter (as C³, Figure 1,)
supposed to be partially or wholly spent or exhausted by the before-
stated destructive distillation process, while the said residuum C¹ is in a
highly heated state. The effect of this inlet or supply of hydrocarbons
to the retorts is to create a second distillation, especially of the lighter
portion of these hydrocarbons, and so far incorporate the heavy part
thereof with the aforesaid residuum of coal and shale, while the lighter

page_text: oils so produced and condensed may again be further treated and
purified with acids and alkalies in the usual manner of distillation.
In case the residuum thereof may be too heavily incorporated or
charged with liquid hydrocarbons a discharge stop-cock may be fitted in
any suitable part of the said retorts or cylinders A, A', for the purpose of
letting off any surplus or excess of liquid. hydrocarbons from the said
residuum fuel or gas producing material C¹, Figure 2, while in a heated
state, and this surplus or excess of liquid hydrocarbons may be returned
to any suitable vessel to be again used in the same way. The residuum
(C¹, Figure 2), of coal and shale mixed with the said organic substances,
or afterwards mixed or ground with the other organic substances before
stated, for producing an illuminating gas fuel, may thus be utilized
by the process thus described, and thus made available for the
purposes herein-before specified, and the temperatures at which theso
cylinders are as before mentioned maintained to suit the respective
products desired, the distillation being carried on regularly, while the
whole fixed carbon or gas producing fuel or charcoal (which may be
ground for blacking or used for other purposes) are all thus regularly,
systematically, and continuously carried forward to the discharge pipe F
at the lower end of the retorts or cylinders A, A¹, and discharged, all as
before stated. The admission of hydrocarbon oils or vapours into the
partially or wholly spent, exhausted, or distilled residuum C of said coal
or shale, or the said organic substances for producing or forming a
second or double distillation may also be carried on in the ordinary
shaped retorts or cylinders without the aid of a rotatory screw or propelling
blades; and the said residuum so treated may afterwards be either used
by itself or ground or mixed along with the said other organic substances
by one or other or all of the aforesaid processes for the production of
illuminating gas, oil, or fuel, and other products therefrom. Should the
material C require compression for feeding it through the charging
hopper or receiver D, E, into the upper part A, B³, of the retort and
conducting screw, then a vertical feeding-in screw may be fitted therein,
cither with or without a close lid or valve, for charging the material
through, fitted above and to one side of the spindle, passed out above it,
so as to be actuated by any convenient motive gearing as the screws B, B¹,
and G are actuated. Ordinary light spring pressure and vacuum valves 1
and 2 are fitted to the top of the close chamber K", Figure 1, or other
R

page_text: convenient part of the conducting or conveying apparatus with a pipe 3,
similar. to n, led off some distance for safety from explosion and the
ignition or burning of the waste escape gases. To facilitate the with-
drawal of the gases from the highly heated fire-clay gas retorts to be
charged with the liquid carbons from the screw retorts A, A, and
maintain a clear exit passage therefrom a jet of steam is injected into its
throat which prevents it from getting carburetted or closed up.
Having now described the nature of my said Invention, and the
manner of performing the same, I may observe that I do not confine or
limit myself to the precise details herein described and shown, as tho
same may be modified without departing from the nature of my said
Invention; but what I consider novel and original, and therefore claim
as the Invention secured to me by the herein-before in part recited
Letters Patent is,―
First. The construction and arrangement of the parts of retorts and
their connecting fittings and apparatus for the continuous and regular
destructive distillation of coal and shale, or a mixture of these with tho
other named organic substances; and also the several modes and means
or processes of performing the said distillation for the production of
illuminating gas, gas fuels, and oils, and other products, all respectively
and substantially in the new or improved manner herein described, and
shown in the accompanying Drawings, or any mere modification thereof.
Second. The construction and arrangement of retorts with conducting
and agitating screws (either with or without sharp teeth and cleaning
scrapers and gear), and the modes and means of feeding and heating
those retorts, and the pipes and screws for withdrawing the residuum
and utilizing the same in the continuous and regular destructive dis-
tillation of coal and shale, or a mixture of these with the other named
organic compounds (whether admitting hydrocarbons during the said
distillation or not), for the production of oleaginous gases at temperatures
about and below the dull red heat, all substantially in the new or
improved manner herein described, and shown in the accompanying
Drawings, or any mere modification thereof.
Third. The construction and arrangement of feeding hopper and
gearing, and discharging mouths or pipes and their automatic screw

page_text: )
retorts, for the continuous destructive distillation of coal and shale,
or a mixture of these with the other named organic substances, all in
the manner and for the purposes substantially as herein described, and
shown in the accompanying Drawings.
Fourth. The construction and use of retorts for the continuous and
regular destructive distillation of coal and shale, or a mixture of these
with the other named organic substances, and for utilizing and treating
the residuum therefrom by means of the admission of liquid hydrocarbons
and gases during the said distillation, together with the necessary con-
struction and arrangement of pipes and ducts for the distillation of the
same, all respectively and substantially in the new or improved manner
hercin described, and shown in the accompanying Drawings.
Fifth. The combustion and use of the residuum from and for tho
heating of the said screw retorts in the destructive distillation of coal
and shale, or a mixture of those with the other named organic substances,
either by itself as an auxiliary to other fuel or waste heated gases from
other fires, furnaces, or retorts, all substantially in the new or improved
manner herein described, and shown in the accompanying Drawings.
'
Sixth. The grinding or mixing the simple residuum after the volatilo
matters have been extracted therefrom by the destructive distillation of
coal and shale, or a mixture of these with the other named organic
substances within and from my said improved retorts at a low tem-
perature, and the utilizing of these ground and mixed residuum for
blacking and other purposes, or the mixing of the said residuum in a
3 cold or hot state when the oleaginous gases have not been wholly
exhausted therefrom with the natural organic substances stated, or with
hydrocarbon oils for being utilized as an illuminating gas fuel, or for
redistillation for extracting the hydrocarbon oils therefrom, all respect-
ively and substantially in the new or improved manner herein described.
Seventh. The admitting and distilling of hydrocarbons and other
oleaginous substances with the residuum (whether they are neutralized
by alkalies, or partially rectified with acids, or otherwise previously so
treated), from the said improved screw retorts in the destructive dis-
tillation of coal and shale, or a mixture of these with the other named

page_text: organic substances, substantially in the new or improved manner nerein
described.
In witness whercof, I, the said John Patison, have hereunto set my
hand and seal, this Thirtieth day of July, in the year of our Lord
One thousand eight hundred and soventy-three.
Witness,
W. R. M. THOMSON,
Patent Agent,
62, Buchanan Street,
Glasgow.
JOHN PATISON. .(L.S.)