Improvements in the Production of Gas by the Use of Electricity.
Year: 1894

page_text: Date of Application, 12th Oct., 1894
Complete Specification Left, 12th Aug., 1895-Accepted, 12th Oct., 1895
Improvements in the Production of Gas by the Use of Electricity.
I JOHN HENRIQUE DUNN of 8 Spencer Road Holloway in the County of
London Surveyor, Railway Engineer and Accountant do hereby declare the
nature of this invention to be as follows:-
My invention is for a process or system of combustion by the use of the electric
are or other form of electricity for the purpose of producing gas from coal or other
fuel or other combustible materials.
1 employ a retort having necessary outlets to collectors or condensers and so
constructed as to receive two carbon conductors so arranged in parallel having a
non-conducting material in centre for the purpose of fixing the arc by which a
small carbon connection is attached on the carbon ends for the purpose of
commencing the arc.
The coal, fuel or other combustible material is then placed in the retort
surrounding the carbon conductors or are forming bodies. The lid or lids is or are
then placed on the retort having two metallic connectors inserted and so arranged
as to make electric contact to the carbon conductors.
The electric current being then turned on, the arc produces a high state of
incandescence and perfect combustion reducing the coal fuel or other combustible
to gas and leaving little or no residue.
Dated this 12th day of October 1894.
Improvements in the Production of Gas by the Use of Electricity.
I, JOHN HENRIQUE DUNN, of 8 Spencer Road, Holloway, in the County of
London, Surveyor and Accountant do hereby declare the nature of this invention
and in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement :-
The object of my invention is the production, by the use of electricity, of gas
from coal or other fuel such for example as petroleum or other liquid hydrocarbon
or other carbonaceous matter, in a rapid and efficient manner, and this I effect by
means of the electric are in the presence of the material from which the gas is to
be produced.
i
I will describe my invention with reference to the accompanying drawing
premising however that I do not restrict myself to the precise arrangements of
apparatus illustrated and described.
According to my invention I provide the chamber or retort in which the gas is
to be generated with electric conductors arranged in pairs after the manner of the
carbons of an electric arc lamp the several pairs of carbons, in the case of using
more than one pair, being either worked in series or in parallel as desired. The
carbons may be carried in tubes inserted in holes provided in opposite sides of the
chamber or retort the inner ends of the carbons of each pair preferably meeting, so
as to form the are, about midway between the said opposite sides of the chamber or

page_text: retort. The liquid hydrocarbon or carbonaceous matter to be gasified is introduced
into the chamber or retort through suitable passages and is caused to surround or
cover the carbon conductors, and the chamber or retort being closed the current of
electricity is turned or switched on, and the arcs struck between the pairs of
carbons whereupon a high degree of temperature is produced which rapidly
generates gas from the liquid hydrocarbon or carbonaceous matter contained in the
chamber or retort the gas produced passing from the chamber or retort and being
subjected if required to any usual or suitable purifying processes.
Figure 1 represents in longitudinal section an arrangement for producing gas
from liquid hydrocarbon by means of electricity according to my invention.
Figure 2 is a transverse section of the same.
Figure 3 is a longitudinal section of one of the carbon holders drawn to a larger
scale and
Figure 4 is a detail showing an arrangement for automatically breaking the
electric circuit when the liquid in the chamber or retort falls below a certain
level.
Figure 5 is a longitudinal section of a portion of a retort litted with my inven-
tion for producing gas from coal or other solid carbonaceous matter by means of
electricity and Figure 6 is a transverse section of the same.
Referring to Figures 1 to 4 A is a chamber or retort in which the gas is to be
produced from liquid hydrocarbon which I will refer to as oil. The oil is supplied
to the chamber or retort A from a tank B through a pipe C provided with a stop-
cock c by which the flow of oil therethrough may be regulated or stopped as
required. The lower end of this pipe communicates with a chamber a provided
with a valve through which the oil must pass to enter the chamber or retort A
which valve is connected to a float d which when the oil is at a certain level in the
retort A causes the valve to close the passage for the oil into the retort, and to
open the passage when the level of the oil sinks below the desired level thereby
automatically maintaining the level of the oil uniform. Oil is supplied to the
tank B from a main reservoir through the pipe e which is fitted with a float valve f
so as to maintain a constant level in the said tank. The two opposite sides of the
retort A are provided with holes to receive carbon electric conductors D arranged
in pairs similar to the carbons of are electric lamps the holders of which carbons
consist of tubes D' in which the carbons are free to slide under the action of
springs g as shewn in Figure 3 to maintain the arc. The ends of each pair of
carbons may be normally in contact or placed at such a distance apart as to prevent
the arc being formed and when the current is switched on, the tubes D' are slidden
in their holes so as to bring the ends of the said carbons into position to strike the
As the said carbons wear away they are pressed forward in their holders by
the springs g so as to maintain the are, stops d² being provided to prevent the
carbons from being forced too far through the tube. The oil in the chamber or
retort entirely covers the carbons so that when the arcs are struck the heat there-
from rapidly gasifies the said oil the gas generated escaping through the pipe E by
which it may be conducted into a gas holder direct but I prefer to pass it first
through a condenser F wherein any ungasified vapour that may escape with the
gas becomes condensed and passes therefrom by the pipe into the supply pipe C
and is again conducted into the retort A. G is a safety device for breaking the
electric circuit should the level of the oil in the retort A from any cause sink
below a predetermined point. This safety device is shown drawn to a larger scale
in Figure 4 and consists of a weighted lever H connected to a piece I in the
electric circuit the said weighted lever being supported, when the level of the oil is
at the required height, by means of a float K carried on one arm k of a bell crank
lever the other arm of which bell crank engages a projection i on the weighted
lever H. Should the level of the oil sink below the normal the float K will sink
with it and remove the arm of the bell crank out of engagement with the pro
jection on the weighted lever whereupon the said lever will suddenly turn with
the piece I on its fulcrum into the position shown by dotted lines and so break the
arc.

page_text: circuit. The spindle carrying the piece I and weighted lever H passes to the
exterior of the chamber or retort A and may be provided with a handle for
returning the lever H and piece I to their normal position when the normal level of
the oil is restored. L is a gauge to shew the level of the oil in the chamber or
retort A.
For producing gas from coal or other solid carbonaceous material by means of
electricity according to my invention an ordinary D or other retort may be
employed as shown for examples in Figures 5 and 6 the carbons D for striking the
arcs being fitted in holes in the sides of the retort and may be operated to strike
the arc by mechanism similar to that employed in an electric arc lamp or other
convenient means. The retort A is preferably provided with a false bottom M
having grooves or recesses to receive the carbons, so that they may be protected
from injury when the coke or refuse is being drawn from the retort, perforations m
being made in the false bottom where the arcs are formed through which perfora-
tions the heat passes to the carbonaceous material placed in the retort upon the
false bottom M. The gas produced escapes from the retort in the ordinary
manner by the ascension pipe E and may be treated in the same manner as gas
made from coal in the usual manner.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is:-
1. The production of gas from coal or other solid carbonaceous material or
from liquid hydrocarbons by means of electricity substantially as hereinbefore
described.
2. For the production of gas from coal or other carbonaceous material or from
liquid hydrocarbons, by means of electricity, a chamber or retort provided with
conductors arranged to form electric arcs in the said chamber or retort to effect
the production of gas from the carbonaceous material or liquid hydrocarbon fed
into the said chamber or retort substantially as herein before described.
Dated this 12th day of August 1895.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.