IMPROVEMENTS IN THE MANUFACTURE OF GAS, AND IN THE APPARATUS EMPLOYED THEREIN
Year: 1873

page_text: PROVISIONAL SPECIFICATION left by David Allan Graham at the
Office of the Commissioners of Patents, with his Petition, on the
28th June 1873.
I, DAVID ALLAN GRAHAM, Engineer and Manager of the Gas Works,"
Stalybridge, in the County of Chester, do hereby declare the nature of:
the said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF GAS, AND IN
THE APPARATUS EMPLOYED THEREIN," to be as follows:-
.
This Invention has reference to an improved method of manufacturing
gas by the application of certain mechanical and chemical arrangements,'
whereby the gas so manufactured is greatly increased in purity, illu-
minating power, and in quantity, this result being effected in tho
following manner :-
First. I manufacture gas in the manner commonly in use, namely,
place the coal, or cannel, or both, in retorts, and subject it to destructive
distillation; pass it through horizontal condensers, whereby the
naphthaline present in it is partially removed while in contact with
the tar which is made to flow along with it, and the naphtha present in
the tar is partially absorbed by the gas in its passage over and in contact
with the tar.
1
-O

page_text: Second. I allow the tar which leaves these condensers to fall into a
well, from which it is pumped or allowed to descend by gravitation
alternately or in rotation into two or more boilers or stills, in which I
volatilize or convert into vapour the naphtha or other illuminants capable
of being converted into vapour or permanent gas. Separate or the
same vessels may also be used to heat, distill, or render gaseous, or
convert into vapour any other mineral or vegetable oils which it may be
found convenient to use, these being either mixed with the tar or
distilled separately in other vessels.
Third. In a separate boiler or vessel I generate steam, and pass it
through a red hot tube filled with iron borings, or I decompose water by
means of zinc and sulphuric acid or by means of potassium or any other
of the methods of producing hydrogen in common use. I mix this
stream of hydrogen gas with the vapours, gases, or other illuminants
present, and issuing from the vessels containing the tar, naphtha,
petroleum, or other illuminating substances, and pass them while in a
gascous or vapoury condition, and I mix or diffuse them in two or a
series of chambers on the outlet (but no necessarily on the outlet of the
exhauster), or if found more convenient on the outlet of the first set of
purifiers. I alternately, if two chambers are used, or in rotation if more,
fill these chambers with the common coal, gas being mufactured, and
with such proportional quantity of the naphtha or other vapours or
gaseous matter, together with such quantities of hydrogen gas as may be.
found most advantageous, and when these are so filled I isolate them
alternately or in rotation, as may be required, andI then pass an electric
spark, or an intermittent series of electric sparks, or any separate number
of electric sparks through the mixture of vapours and gases, thereby
converting the vapours, coal, gas, and hydrogen gas, into a permanent
gas of greater illuminating power, and of considerably greater volume
than the original constituents in the explosion chambers. I morcover
convert the bisulphide of carbon present into sulphuretted hydrogen
which is easily removed by the ordinary oxide purification commonly in
use. The advantages attending this mode of manufacture is a greater
amount of purity in the gas obtained, being freer from sulphur com-
pounds, a much larger return of gas per ton of coal used, a much greater
amount of illuminating power in the gas produced, and conversion of the
tar into pitch suitable for marketable purposes.

page_text: The second part of my improvements refers to a peculiar arrangement
of explosion chambers whereby I isolate certain portions of the gas, and
the mixture of hydrogen gas, naphtha, or other oils, or vapour of oils, and
subject their isolated contents to the action of the electric spark. These
chambers I submerge in tanks and pass a current of water, brine, or
other suitable liquid over them, thereby abstracting a portion of the heat
due to a continuous scries of explosions. I thereafter pass this new
permanent gas on through another set of condensers, the scrubbers,
purifiers, &c., to remove its impurities in the usual manner; or I first
pass the gas manufactured in the ordinary way through the ordinary
process, and place these explosion chambers on the outlet of the first sct
of purifiers, and after exploding their contents pass them through
another condenser and a set of purifiers without scrubbers being used
after the gases and vapours have been diffused or mixed and exploded,
and I thereafter pass the new permanent gas into the gas holder to be
stored and ready for use.
My Invention also refers to a peculiar method I use of isolating
portions of the continuous make of coal gas, naphtha, vapours and
hydrogen in one vessel, and so explode these as not to hinder the con-
tinuous flow of the make of gas into other vessels. While I so operate
by means of electricity and explode the contents of each vessel yet in
such manner as shall not allow the effects of the explosion to be carried
into the gases outside of these vessels. This I accomplish by a peculiar
arrangement of valves or other mechanism, whereby the gas in these
explosion chambers is entirely and safely isolated from the gas being
made, and the gas being forced on for purification or storage.