IMPROVEMENTS IN THE MANUFACTURE OF GAS AND IN APPARATUS THEREFOR."
Year: 1877

page_text: LETTERS PATENT to Frederick Deacon Marshall, of Cambridge Street, in the
County of Middlesex, Engineer, for the Invention of "IMPROVEMENTS IN THE
MANUFACTURE OF GAS AND IN APPARATUS THEREFOR."
PROVISIONAL SPECIFICATION left by the said Frederick Deacon Marshall
at the Office of the Commissioners of Patents on the 27th June 1877.
FREDERICK DEACON MARSHALL, of Cambridge Street, in the County of Middlesex,
Engineer. " IMPROVEMENTS IN THE MANUFACTURE OF GAS AND IN APPARATUS
THEREFOR."
"
My Invention relates to improvements in the manufacture of gus, and to apparatus
for carrying the same into effect.
The main feature of my said Invention is the introduction of carbonaceous oil
and steam into the retort by means of an injector or jet apparatus. I prefer to use
crude petroleum foil, but other carbonaceous oils may be employed, and I may
employ either ordinary wet steam or superheated steam, hot air, or hydrogen gas
for injecting the same. By this method of introducing the oil by a jet of steam,
air, or hydrogen, the oil will enter the retort in a very fine spray or vapor, and
coming in contact with the red-hot surfaces of the retort, will be immediately con-
verted into gas of a highly illuminating value.
I may use any suitable or convenient injector or apparatus for injecting the oil
into the retort, but prefer to employ an apparatus somewhat similar to the ordinary
feed water injectors of steam boilers. The nozzle of this injector is to be secured
upon the exterior of the retort lid, and the said apparatus must be supplied with
oil from a cistern or reservoir, arranged in any convenient position, the steam or
other injecting fluid being supplied from a boiler by means of suitable pipes furnished
with regulating valves or cocks.
My improved method of combining the oil with the gas may be employed in
connection with any ordinary retorts, as at present existing in gas-works, but my

page_text: Invention comprises special forms of retorts and a mouth-piece, which I prefer to
employ in practising my Invention.
I construct what I term a right angled retort as follows, that is to say:-I
construct the same in the form of an elbow, its two ends being arranged at right
angles, or nearly so, to each other. I also construct a diaphragm retort, which has
a cylindrical form, with a central division plate extending from the mouth-piece
nearly to the back of the retort. These improved retorts may be formed of either
iron or clay.. I employ two retorts, placed one above or higher than the other. In
the lower one of these the gas is produced in the usual manner, while the petroleum
or other oil is injected into the upper retort, the latter being termed the oil
retort.
My improved mouth-piece is constructed in the forin of a double mouth-piece,
one part being attached to the gas retort, and the other part to the oil retort. These
two parts of the mouth-piece are connected by a tube, which has an extension
inside the said oil retort arranged in the direction of the length of the said retort
and opening into the same. By means of this tube the gas made in the lower
retort ascends into the upper or oil retort, and is there combined or mingled with
the oil vapour, as above described, and is conducted away from the same in any
convenient manner.
By the improved method or process above described I manufacture a permanent
gas of a high illuminating value. This gas is designed principally as an " enricher"
of coal gas or as a substitute for cannel gas, and can be made at a much cheaper
rate than gas of equal illuminating power heretofore manufactured.
...

page_text: necting pipe or tube between the two said retorts. In the lower of these retorts
the gas is produced in the usual manner, while the petroleum or other oil is injected
into the upper retort.
My improved mouth-piece, as shewn in Figure 2, is constructed in the form of a
double mouth-piece, one part being attached to the gas retort h, and the other
part m to the oil retort i. These two parts l, m, of the mouth-piece are connected
by the tube , which has an extension n inside the said oil retort arranged in the
direction of the length of the said retort, and opening into the same. By means of
this tube the gas made in the lower retort ascends into the upper or oil retort, and
is then combined or mingled with the oil vapor, as above described, and is conducted
away from the same in any convenient manner.
If desired a series of retorts may be connected in the same manner instead of only
two, as above described.
By the improved method or process above described I manufacture a permanent
gas of a high illuminating value. This gas, as above stated, is designed principally
as au "enricher" of coal gas, or as a substitute for cannel gas, and can be made at
a much cheaper rate than gas of equal illuminating power heretofore manufactured,
The said injector may be attached to any ordinary mouth-piece, but I prefer to
employ the mouth-piece shewn in Figure 2 of the Drawing, and above described.
When steam is used, the same may be superheated by passing it through a
wrought-iron worm or coil set in a suitable furnace, and I prefer to employ iron
retorts for carbonizing purposes, lined with fire-clay or some other refractory
substance.
When compressed gas is used as an injecting medium, the gas will be compressed
in strong metal cylinders, and the hydrocarbon liquid to be injected may be stored
in the said cylinders together with the compressed gas or may be supplied from a
separate reservoir.
68
I modify my apparatus for injecting the hydrocarbons by so constructing it as
to utilize the vapour generated or formed by heating the hydrocarbon oil in a
digester" or boiler heated by a steam jacket or coil or oil bath. In this case the
injector or jet apparatus may be affixed either to the boiler or "digester," and the
vapour of heated hydrocarbon made to inject the hydrocarbon itself into the retort,
or the hydrocarbon vapour may be produced in one boiler and conveyed to the said
injector or jet apparatus, and the liquid hydrocarbon may be supplied to this injector
or jet apparatus from a separate reservoir.
"s
In Figure 3 I have shown this apparatus for injecting hydrocarbons by means of
their own vapor under pressure. p represents a strong boiler or digester" heated
by means of a steam coil g, which is fed through the pipe from a superheater fixed
in the flue of the retort setting. The said boiler is filled up to the levels with
hydrocarbon liquid, and heated as described till the required pressure is obtained in
the apparatus. The hydrocarbon liquid enters the nozzle or jet apparatus j through
the pipe u, and is met by vapour under pressure from the pipe v, and the two are
injected into the retort Å in the form or condition of fine vapour or spray. t, t¹, t², t³,
are stop-cocks for controlling the supply of vapour and liquid through the pipes u, v.
Should it be necessary superheated steam may be applied to the nozzle or jet
apparatus by an intermediate pipe extending from the pipe to the pipe u. wis a
supply pipe from a reservoir, and through which the liquid is fed by a pump;
a check valve in this pipe; y is a level gauge; y¹ is a safety valve; y², a pressure
gauge.
is
Should the injector or jet apparatus be used to carbonize hydrocarbons whose
component parts vary in specific gravity, and are volatilized or converted into
gas at varying temperatures, a special carbonizing or "fractionating" process will
be employed, and for this purpose the retorts will be set in such a manner as to be.
capable of being heated each to a distinct temperature. I carry this process into
practice as follows:-The oil or hydrocarbon being first injected into No. 1 retort,
heated to a low temperature, the lighter portions of the hydrocarbons (namely, those
which are volatilized at a low temperature) are here decomposed and converted
'

page_text: into permanent gas, while the heavy hydrocarbons pass away as vapour, and are
condensed again in a liquid form. These condensed gases are again in their turn
subjected in a retort to a higher temperature than the preceding, and the next series
of hydrocarbons are converted into permanent gas, while the vapours of the heaviest
constituents pass away, are condensed, and are in their turn subjected in a retort to
a higher temperature than any of the former. The number of retorts employed will
vary with the description of hydrocarbons to be carbonized. By adopting this
method of carbonizing I convert the whole or nearly the whole of the constituents.
of the hydrocarbons into permanent gas, whereas if the retorts were heated to an
even temperature, some of the constituents of the hydrocarbons would be decom-
posed and thrown down as carbon, while hydrogen would be liberated, and others
would be merely converted into vapour and condensed again into a liquid form on
leaving the retorts, and but a small per-centage would be actually converted into a
permanent gas.
Should hydrocarbons, such as pitch, tar, resin, or creosote, be employed, they will
be liquefied by a coil of superheated steam passing through them.
Having thus fully described my said Invention and the mauner of performing
the same, I wish it understood that I claim,―
First. Improving the quality of coal gas by the injection of hydrocarbons for the
purpose of enriching the gas, as above set forth.
Second. An injector or injecting or jet apparatus, as described and as shewn in
Figure 1 or in Figure 3 of the Drawing, for injecting hydrocarbons into the coal
gas for the purposes of my Invention, as above set forth.
Third. The mouth-piece provided with a connecting tube between the lower and
upper retorts for the purpose of mingling the gases, as above set forth.
Fourth. The modification of my Invention wherein I employ the carbonizing
or fractionating process, whereby the whole or nearly the whole of the hydrocarbons
are converted into permanent gas, as above described.
In witness whereof, I, the said Frederick Deacon Marshall, have hereunto set
my hand and seal, this Twenty-fourth day of December, in the year of our
Lord One thousand eight hundred and seventy-seven.
F. D. MARSHALL. (L.S.)