IMPROVEMENTS IN THE MANUFACTURE OF GAS FOR ILLUMINATION,
Year: 1871

page_text: LETTERS PATENT to Robert Porter and Thomas Lane, Engineers, both
of 172, Fenchurch Street, in the City of London, for the Inven-
tion of "IMPROVEMENTS IN THE MANUFACTURE OF GAS FOR ILLUMINATION,
PROVISIONAL SPECIFICATION left by the said Robert Porter and
Thomas Lane at the Office of the Commissioners of Patents, with
their Petition, on the 25th January 1871.
We, ROBERT PORTER and THOMAS LANE, Engineers, both of 172,
Fenchurch Street, in the City of London, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF GAS
FOR ILLUMINATION, AND IN THE APPARATUS CONNECTED THEREWITH," to be as
follows:-
For the production of gas from oil or other liquid hydrocarbons we
use a vertical retort (or retorts.) of the form of an inverted hollow cone
or frustum of a cone, or other similarly tapered form.
Inside and
around the upper part of the retort we make a channel, into which the
oil or other liquid flows from a syphon pipe leading from any suitable

page_text: reservoir, and out of which channel the liquids overflow down the sloping
surface of the retort. At the lower end the retort is open and con-
nected with a main for conducting the gas away. The retort is closed
at the top with a lid secured with a luted or other gas-tight joint.
Within the retort we fix or suspend one or more diaphragms or discs
or other similar obstructions so as to leave a small space between their
outer edges and the interior surface of the retort, by which means the
vapours or gases arising from the liquid overflowing from the channel
are forced into contact at intervals with the heated surface of the retort
in passing by the edges of the diaphragms or discs in order to convert.
them into fixed gas before they reach the lower extremity of the retort.
When the diaphragms are suspended we make the rod or chain upon
which they are hung to work freely but gas-tight through a hole in the
lid of the retort, so that they may be lifted directly or by means of
a screw or lever, or by any other means, to clear their edges of any
carbonaceous deposit that may adhere to them.
For regulating the supply of the liquid to the retort we employ a
vessel hermetically closed except at the outlet on the side at or near the
bottom of the vessel, which outlet we make preferably of a nearly semi-
circular shape, and to it we attach the end of a horizontal trough or
spout of a suitable length closed at the other end, and of any suitable
shape or section, but with the sides extended up a little above the level
of the horizontal line of the top of the semicircular outlet, and at or
near to the other end of the trough we cause a slide stop or valve or an
open vertical pipe to pass up liquid tight through the bottom of the
trough, and capable of being raised or lowered. The action is such that
when the top of the vertical pipe or slide is raised a little above the
level of the top of the outlet in the vessel the liquid in the trough rises
to the same level, and prevents any air passing into the vessel, thereby
stopping the flow of the liquid, and vice versa, when the top of the
vertical pipe is lowered below the level of the top of the outlet in the
vessel the level of the liquid in the trough falls with it and allows air to
pass into the vessel, which causes the liquid to flow freely and con-
tinuously in a larger or smaller stream at the operator's will along the
trough and down through the open vertical pipe or over the slide top
into the syphon leading into the retort. By these means thic hitherto
insuperable difficulty of maintaining a regular and continuous flow of
liquid of the proper quantity to the retort through a small tap or a large
tap partially closed is practically overcome.

page_text: Water or steam may be introduced with advantage into the retort
to unite with the gases evolved from the hydrocarbon in order to prevent
any injurious formation of carbonaceous deposit, as well as for the
increased production of gas by the decomposition of the water or steam
within the retort. For this purpose we place an open pan or a closed
vessel in the upper portion of the retort (above the-overflowing channel),
which pan or vessel we fill with water through a special syphon or
otherwise, and the pan we proportion in size and thickness, and shield
when necessary so as to evaporate the quantity of water requisite, or the
steam or water may be otherwise introduced into the retort.
Around the retort we construct a brickwork or brick-lined oven, which
we heat by means of a furnace connected with the oven by a fluc or
flues in such a manner that the retort shall not be in direct contact
with the fire in the furnace nor exposed to the direct action of the heat
from the furnace, but so shielded in all parts as only to receive the
heat from the furnace after the gases have been well mixed and a good
combustion insured in order to prevent as much as possible the oxidation
of the retort, and for this purpose we build a brick dead surface pre-
ferably about four and a half inches. wide running on a level with
the grate bars between the grate and the sides and end wall of the
furnace, which entirely prevents any air from drawing up between the
fuel and the walls of the furnace, thereby preserving the retort from
undue oxidation, and entirely doing away with clinkers on the furnace
walls.
Also for better combustion of the fuel in furnaces used for heating
retorts for the production of gas for illumination, we cause the top of
the flue or flues leading out of the furnace to be as low-or somewhat
lower than the springing of the arch of the furnace, thereby forming a
combustion chamber in the crown of the arch in which the gases rising
from the fuel are held for a while to undergo a more complète admixture
and combustion than when allowed to pass straight away unchecked
through flues in the arch, or any other suitable furnace may be used to
heat the retort.
For the production of gas from coal or other solid materials we use a
vertical retort (or retorts) open at both ends and of a gradually increasing
diameter towards the lower end. The upper end of the retort is con-
nected with a hopper or reservoir for the charge, and at the lower end
with a chamber for the reception of the coke or exhausted material.

page_text: Inside the retort we fit a worm or screw of a diameter somewhat less
than the internal diameter of the retort, and we fix the said worm
centrally in the retort in bearings upon a cross bar at each end cast on
to the retort or firmly fastened to it, so that the worm may be turned
with an axial motion by means of a lever or gearing acting upon the
central core or shaft, which core or shaft we extend beyond the bearings
through the cover of the hopper for the purpose, and upon the said
extension of the shaft within the hopper we fix another screw or one or
more arms for stirring the charge and causing it to fall freely towards
the entrance of the retort.
The upper chamber or hopper is made perfectly gas-tight, and pro-
vided with a feed hole fitted with a lid for charging the hopper.
The lower chamber or coke box is also made gas-tight, and is provided
with an opening fitted with a door or lid for withdrawing the exhausted
charge.
A pipe is also fitted to the lower chamber for coke box for taking away
the gas produced. We employ for heating the retort a furnace similar
to that as hercin-before described.
For condensing gas we make a condenser of one or more horizontal
pipes or conduits partly filled with water, so that the gas which is made
to pass through the said pipe or series of pipes shall pass over and in
contact with the water therein, as well as in contact with the other
interior surfaces of the pipes not covered by the water.
And we sometimes make the said condensing pipes with a trough-
shaped top, so as to carry a top covering of water for the more effectual a
condensation of the gas within.
For purifying the gas we adopt the ordinary processes, but we prefer
to use a wrought-iron purifier vessel, for which we make the trough for
the water luting joint for the cover of an angular or slightly OG form
of bent plate iron, by, which means much costly.. work is avoided in
making the said water luting troughs as compared with those of the
shapes hitherto made and in use.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Robert Porter and Thomas Lane in the Great
Seal Patent Office on the 25th July 1871..
TO ALL TO WHOM THESE PRESENTS: SHALL COME, we, ROBERT
PORTER and THOMAS LANE, Engineers, both of 172, Fenchurch Street,
in the City of London, send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-fifth day of January, in the
year of our Lord One thousand eight hundred and seventy-one, in the
thirty-fourth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto us, the said Robert Porter and Thomas
Lane, Her special licence that we, the said Robert Porter and Thomas
Lanc, our executors, administrators, and assigns, or such others as
we, the said Robert Porter and Thomas Lane, our executors, adminis-
trators, 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
MANUFACTURE OF GAS FOR ILLUMINATION AND IN THE APPARATUS CONNECTED
THEREWITH," upon the condition (amongst others) that we, the said
Robert Porter and Thomas Lanc, our executors or administrators, by an
instrument in writing under our, or their, or one of their hands and
scals, 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 Robert Porter and Thomas Lane,
do hereby declare the nature of our said Invention, and in what
manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
For the production of gas from oil or other liquid hydrocarbons we uso
a vertical retort (or retorts) of the form of an inverted hollow cone or
frustum of a cone or other similarly tapered form. Inside and around
the upper part of the retort we make a channel, into which the oil or
other liquid flows from a syphon pipe leading from any suitable reservoir

page_text: and out of which channel the liquids overflow down the sloping surface
of the retort. At the lower end the retort is open and connected with
a main for conducting the gas away. The retort is closed at the top
with a lid secured with luted or other gas-tight joint. Within the
retort we fix or suspend one or more diaphragms or discs or other
similar obstructions so as to leave a small space between their outer
edges and the interior surface of the retort, by which means the vapours
or gases arising from the liquid overflowing from the channel are forced
into contact at intervals with the heated surface of the retort in passing
by the edges of the diaphragms or discs in order to convert them into
fixed gas before they reach the lower extremity of the retort. When
the diaphragms are suspended we make the rod or chain upon which
they are hung to work freely but gas-tight through a hole in the lid of
the retort, so that they may be lifted directly or by means of a screw
or lever to clear their edges of any carbonaceous deposit that may adhere
to them.
For regulating the supply of the liquid to the retort we employ a
vessel hermetically closed except at the outlet on the side at or. near
the bottom of the vessel, which outlet we make preferably of a semi-
circular shape, around which we attach the end of an open trough of a
suitable length closed at the other end and of the same shape in section
as the outlet, but with the sides extended up a little above the level of
the horizontal line of the top of the semicircular outlet, and at or near
to the other end of the trough we cause an open vertical pipe to pass up
liquid-light through the bottom of the trough and capable of being
raised or lowered. The action is such that when the top of the vertical
pipe is raised a little above the level of the top of the outlet in the
vessel the liquid in the trough rises to the same level and prevents any
air passing into the vessel, thereby stopping the flow of the liquid, and
vice versa when the top of the vertical pipe is lowered below the level of
the top of the outlet in the vessel the level of the liquid in the trough falls
with it, and allows air to pass into the vessel; which causes the liquid to
flow freely and continuously in a larger or smaller stream at the operator's
will along the trough' and down through the open vertical pipe into the
syphon leading into the retort. By these means the hitherto insuperable
difficulty of maintaining a regular and continuous flow of liquid of the
proper size to the retort through a small tap or a large tap partially
closed is practically overcome.

page_text: Water or steam may be introduced with advantage into the retort
to unite with the gases evolved from the hydrocarbon in order to prevent
any injurious formation of carbonaceous deposit as well as for the in-
creased production of gas by the decomposition of the water or steam
within the retort. For this purpose we place an open pan or vessel in
the upper portion of the retort (above the overflowing channel), which
pan we fill with water through a special syphon or otherwise, and the
pan we proportion in size and thickness, and shield when necessary so
as to evaporate the quantity of water requisite, or the steam or water
may be otherwise introduced into the retort. Around the retort we
construct a brickwork or brick lined oven, which we heat by means
of a furnace connected with the oven by a flue or flues in such a manner
that the retort shall not be in direct contact with the fire in the furnace,
nor exposed to the direct action of the heat from the furnace, but so
shielded in all parts as only to receive the heat from the furnace after
the gases have been well mixed and a good combustion effected in order
to prevent as much as possible the oxidation of the retort, and for this
purpose we build a brick dead surface preferably about four and a half
inches wide running on a level with the grate bars between the grate and
the sides and end wall of the furnace, which entirely prevents any air
from drawing up between the fuel and the walls of the furnace, thereby
preserving the retort from undue oxidation and entirely doing away with
clinkers on the furnace walls.
And for better combustion of the fuel in retort furnaces we cause
the top of the flue or flues leading out of the furnace to be as low or
somewhat lower than the springing of the arch of the furnace, thereby
forming a combustion chamber in the crown of the arch, in which the
gases rising from the fuel are held for a while to undergo a more complete
combustion than when allowed to pass straight away unchecked through
flues in the arch.
For the production of gas from coal or other solid materials we use a
vertical retort (or retorts) open at both ends and of a gradually increasing
diameter towards the lower end. The upper end of the retort is
connected with a hopper or reservoir for the charge, and at the lower
end with a chamber for the reception of the coke or exhausted material.
Inside the retort we fit a worm or screw of a diameter somewhat less than
the internal diameter of the retort, and we fix the said worm centrally in

page_text: the retort in bearings upon a cross bar at each end cast on to the retort
or firmly fastened to it, so that the worm may be turned with an axial
motion by means of a lever or gearing acting upon the central core or
shaft, which core or shaft we extend (beyond the bearings) through
the cover of the hopper for the purpose, and upon the said extension of
the shaft within the hopper we fix another screw or one or more arms
for stirring the charge and causing it to fall freely towards the entrance
of the retort. The upper chamber or hopper is made perfectly gas-tight
and provided with a feed hole fitted with a lid for charging the hopper. The
lower chamber or coke box is also made gas-tight and is provided with
an opening fitted with a door or lid for withdrawing the exhausted
charge. A pipe is also fitted to the lower chamber or coke box for
taking away the gas produced. We employ for heating the retort a
furnace similar to that as herein-before described.
.
For condensing gas we make a condenser of one or more horizontal
pipes or conduits partly filled with water, so that the gas which is made
to pass through the said pipe or series of pipes shall pass over and in
contact with the water therein as well as in contact with the other
interior surfaces of the pipes not covered by the water. And we some-
times make the said condensing pipes with a trough-shaped top, so as to
carry a top covering of water for the more effectual condensation of the
gas within.
For purifying the gas we adopt the ordinary processes, but we prefer
to use a wrought-iron purifier vessel, for which we make the trough for
the water luting joint for the cover of an angular or slightly OG form
of bent plate iron, by which means much costly work is avoided in
making, the said water luting troughs as compared with those of the
shapes hitherto made and in use.
Having explained the nature of our Invention,, we will proceed to
describe with reference to the accompanying Drawing the manner in
which the same is to be performed.
Figure 1 represents a sectional elevation of a gas generator constructed
according to our Invention for generating gas from oil or other liquids
hydrocarbons, including the furnace for heating the same; Figure 2
represents a sectional plan of the said gas generator and of the said
furnace; Figure 3 represents a sectional elevation of a generator for
generating gas from coal or other solid materials or from solid materials

page_text: in combination and saturated with oil or other liquid hydrocarbons; or
the same generator may be used for obtaining gas from oil or liquid
hydrocarbons only instead of the generator represented in Figures 1
and 2. Figure 4 represents a longitudinal section of a horizontal
condenser constructed according to our Invention.
In Figure 1, A is the vertical retort, which by preference we make of
a tapered or inverted conical form, so as to present sloping sides for the
descending flow of the oil or other liquids employed. The retort is closed
at the top with a lid B, and is connected to the condenser by means of the
horizontal arm or main C, which forms the outlet for the gas produced
in the retort, and may be either cast on to the retort or attached thereto
in any convenient manner or position. For generating gas the liquid
hydrocarbon is supplied to the channel D. surrounding the upper part of
the retort through a syphon pipe E leading from any suitable reservoir.
The liquid overflowing from the channel D and descending the sloping
sides of the heated retort is rapidly converted into vapour and gas, and
the said vapour and gas in their course to the outlet C are made to pass
the discs F, F, F, in close contact with the heated sides of the retort, by
which means the vapour which would otherwise escape and be condensed
again to a liquid is made into fixed gas. The said discs may be of
any shape, and may be suspended or otherwise fixed in the retort. We
also use similar discs or obstructions fixed in retorts placed in any other
position for the purpose of causing the vapours to pass close to the sides
of the said retorts.
When water or steam is used with the oil for the purposes herein-before
described we supply the said water along with the oil through the same
pipe E, or by a separate pipe, as O, which may deliver the water directly
into the retort or into a pan fixed in the upper part of the retort, as
herein-before described, but we prefer to use superheated or high-pressure
steam instead of water, and H represents a small boiler suspended or
fixed in the oven or flue surrounding the retort. The said boiler
evaporates the water which drops into it from the pipe O, and the steam
resulting issues into the retort, or steam may be supplied from
any other
available source. K is the furnace, and L is the flue leading from the
furnace into the oven I which surrounds and heats the retort, and the oven
is connected to the chimney by means of another flue at any convenient.
point, but preferably from near the bottom of the oven. The sides of

page_text: +
the furnace and oven are constructed of brickwork lined with fire-brick,
as shewn. M, M, M, represents the dead surface on the same level as
the top of the grate bars, and N is the combustion chamber formed in
the furnace above the level of the top of the exit flue L.
In Figures 1 and 2 M, M, M, are the dead surfaces, which we make of
brick, iron, or of any other suitable material, and N represents the
clevated arch forming a space for a combustion chamber above the level
of the flue or flues leading into the ovens around the retort.
In Figure 3, A is the retort, which we fix vertically or in any other
suitable position; and B, B, is the hopper or reservoir for the charge,
which may be of any suitable shape, Ba being the lower part or neck of
hopper connecting it with the retort; C is the chamber or receptacle for
the coke or exhausted material; D is the worm or screw within the
retort; E is the central shaft of screw, and F the upper or feed screw
fixed on the extension of the shaft above the retort, or when convenient
it may be made in connection with the said worm proper to the retort
together in one casting or piece. The retort is heated by means of a
furnace and oven similar to that herein-before described for the oil gas
generator, or it may be heated by any other suitable means.
For generating gas from coal or other solid materials a feed screw is
employed, as at F, of a less pitch or capacity than that of the worm in
the retort if the coal or material be of a nature to cake or swell an
increased bulk under the process of carbonization, as is the case with
many descriptions of coal. By this means the supply of coal to the
retort is apportioned so that there shall be sufficient space in the retort for
the increase of bulk and for the free evolution of gas from the charge in
its passage through the retort. The hopper is charged with coal or other
suitable material through the charge hole, which is then closed with the
lid G, which is made gas-tight by means of luting or otherwise. Upon
turning the shaft E by means of the levers H, H, or by any other
suitable means or gearing the feed screw and the worm in the retort are
caused to revolve together, and a portion of the charge is thereby taken
from the hopper and passed into the retort, where it is retained until all
the gas has been given off, when by further revolution of the screw the
exhausted portion of the charge is expelled from the retort into the
receptacle C, and a fresh portion is simultaneously taken from the hopper
and passed into the retort. The exhausted charge is subsequently
A

page_text: withdrawn through the opening K, which is closed during the operation
of making gas by an ordinary luted lid. The gas evolved into the retort
passes into the lower chamber C, and is conducted thence through the
outlet I into an ordinary hydraulic main or dip and to the condenser.
For making gas from oil or other liquid hydrocarbon in combination
with solid materials the said solid materials are first saturated and mixed
with the oil before charging the hopper, and afterwards the process is
the same as herein-before described for making gas from coal or other
solid materials.
For making gas from oil or other liquid hydrocarbons only with this
generator the oil is introduced by means of a syphon pipe precisely as
herein-before described and illustrated on the Drawing for the other
generator, Figures 1 and 2, except that the oil is made to flow on to the
upper portion of the screw, and in descending the winding surface of
the blade or thread of the screw and in its passage through the retort it
is converted into gas..
In Figure 4 A, A, A, are the horizontal pipes of which the condenses
is formed in any number of pipes requisite, partly filled with water and
the products of condensation; B, B, B, are the stops or drains for
retaining the said water or liquids, and C is the overflow pipe through
which the excess of tar and products of condensation pass into a tar tank.
The upper end of the condenser is connected with the hydraulic main or
dip box, the tar from which may be allowed to overflow and pass into
and through the condenser with the other products of condensation
and with the gas, which is much improved by contact with the said
products. From the condenser the gas is taken through the purifier to
the holder in the usual way, or through an intermediate scrubber if one
is used.
Having thus described the nature of our Invention, and the manner
in which the same is to be performed, we do not limit ourselves to the
precise details herein described and illustrated, as the same may be varied
without departing from the nature of our Invention; but we claim as
our Invention of improvements in the manufacture of gas for illumination
and the apparatus connected therewith,-
Firstly. The improvements substantially as herein-before described
and illustrated in the accompanying Drawing in the manufacture of gas

page_text: for illumination from oil and other liquid hydrocarbons and from coal
and other materials.
Secondly. The improvements in the construction of gas generators for
the manufacture of gas for illumination from oil or other liquid hydro-
carbons with vertical retorts with discs or similar obstructions fixed or
suspended therein, substantially as herein-before described and illustrated
in the accompanying Drawing.
Thirdly. The improvement in fixing discs or similar obstructions in
retorts of any shape and in any position for forcing the vapours to the-
sides of the retort, substantially as herein-before described and illustrated
in the accompanying Drawing.
Fourthly. The improvement in the construction of furnaces for heating
gas retorts with dead surfaces at the level of the top of the grate bars
and with space for combustion above the level of the flues leading to
the retorts, substantially as herein-before described and illustrated in the
accompanying Drawing.
Fifthly. The improvement in gas generators constructed with a vertical
retort connected with a chamber on top for holding the charge and with
another chamber at bottom for the reception of the exhausted material,
and with a worm or screw fixed or suspended within the retort, and
having an upper or feed screw or arms fixed on the extension of the
centre shaft or core of the screw above the retort, substantially as herein-
before described and illustrated in the accompanying Drawing.
Sixthly. The improvement in making the feed screw or the part of
the screw beyond the entrance of the retort of a different pitch or capacity
to that of the screw within the retort in any case where a retort is used
with an interior screw or worm for passing the charge through it, and in
connection with a hopper or chamber at one end for supplying the
charge, and with another chamber at the other end for the reception of
the exhausted material in whatever position the retort may be fixed,
whether vertically or otherwise, substantially as herein-before described
and illustrated in the accompanying Drawing.
Seventhly. The improvement in making horizontal pipe condensers
so as to retain water or part of the products of condensation within and
along the bottom, part of the pipes composing the condenser by means of

page_text: suitable dams or elevations, substantially as herein-before described and
illustrated in the accompanying Drawing.
In witness whereof, we, the said Robert Porter and Thomas Lane,
have hereunto set our hands and seals, this Twenty-fifth day
of July, in the year of our Lord One thousand eight hundred
and seventy-one.