AN IMPROVEMENT OR IMPROVEMENTS IN AND CONNECTED WITH THE MANUFACTURE OF GAS FOR ILLU-. MINATION
Year: 1831

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
Lowe, Civil Engineer, of the Gas Works, Brick Lane, Saint Luke's, in the
County of Middlesex, send greeting.
WHEREAS His most Excellent Majesty King William the Fourth, by His
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Twelfth day of October, in the second year of His reign, did
give and grant unto me, the said George Lowe, my exors, admors, and
assigns, His special licence, full power, sole privilege and authority, that I,
the said George Lowe, my exors, admors, and assigns, and every of them,"
by myself and themselves, or by my or their deputy or deputies, servants or
agents, or such others as I, the said George Lowe, my exors, admors, or
assigns, should at any time agree with, and no others, from time to time and
at all times thereafter during the term of years therein expressed, should
and lawfully might make, use, exercise, and vend, within England, Wales,
and the Town of Berwick-upon-Tweed, ny Invention of "AN IMPROVEMENT
OR IMPROVEMENTS IN AND CONNECTED WITH THE MANUFACTURE OF GAS FOR ILLU-.
MINATION;" in which Letters Patent there is contained a proviso obliging
the said George Lowe, by an instrument in writing under my hand and
seal, particularly to describe and ascertain the nature of my said Invention,
and in what manner the same is to be performed, and to cause the same to
me,

page_text: be enrolled in His Majesty's High Court of Chancery within six calendar
months next and immediately after the date of the said recited Letters Patent,
as in and by the same (relation being thereunto had) may more fully and
at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
George Lowe, do hereby declare the nature of my said Invention to
consist,-
Firstly, in the introduction of atmospheric air raised to a high degree of
temperature over or on the surface of the fuel in the surfaces of gas works, for
the purpose of uniting with and thus igniting the sulphuretted hydrogen gas,
and also the gases and vapours arising from lime, dreg water, and ammoniacal
liquor introduced under the bars of the furnace, and the products or results of
the ignition of which gases and vapours I direct into condensers, so as to
produce sulphurous acid, which acid I use in purifying gas, as herein-after
described in the third part of my said Invention.
Secondly, in an improved mode of working off the charge from gas retorts
by fitting them with some appropriate apparatus, such as herein-after described,
for that purpose, and by putting the coal in at each end alternately half of the
length of the retort, and at proper intervals, so that the inferior gas evolving
from the portion of coal first introduced may mix with the better gas evolving
from that portion subsequently introduced, thus. making gas of a better
general average quality and in greater quantity than by those modes now
in use.
Thirdly, in an improved mode of rendering gas produced from coal for the
purposes of illumination more free from ammonia and its combinations with
sulphuretted hydrogen and other impurities than heretofore, by the application
of sulphurous acid in solution or combination with steam, or by the application
of muriatic acid in solution or combination with steam, or by the exhibition of
potash in the retorts.
And fourthly and lastly, in the application of a new apparatus to retorts,
coke ovens, or furnaces of gas works, for the purpose of receiving the hot
coke drawn therefrom and generating gas by means thereof.
And in further compliance with the said proviso, I, the said George Lowe,
do hereby describe the manner in which my said Invention is to be performed,
by the following description thereof, reference being had to the Drawing
annexed, and to the figures and letters marked thereon (that is to say) :-
Firstly, as to the introduction of atmospheric air raised to a high degree of
temperature over or on the surface of the fuel contained in the furnaces of gas
works and the manufacture of sulphurous acid, as herein-after explained.

page_text: Figure 1 is a longitudinal section, and Figure 2 a transverse section, of a
furnace containing three retorts; Figure 1 shewing also the hydraulic mains
with the dip and bridge pipes which connect them with the retorts, and
which will be more particularly explained under the second head of my said
Invention.
It may be as well here to observe that similar letters of reference are used
to denote similar parts in both Figures 1 and 2. The parts marked A are the
retorts, those marked B the dip pipes, those marked C the stand or perpendi-
cular pipes; J, J, the hydraulic mains; D, D, D, the furnace; E, E, E, the
grate bars; F, F, F, the ash pit; G, G, G, pans containing lime, dreg water,
or ammoniacal liquor as now in common use, in addition to which pans a pipe
will, of course, be added, when sulphuretted hydrogen gas s to be introduced
under the bars, as heretofore practised; H, H, H, H, the first or entrance air
flue, and which air flue extends to near the centre of the furnace, where,
by a perpendicular opening, it communicates to the upper air flue K, K, K, K,
of the same capacity as the first, and which air flue finally communicates
with the furnace by the openings marked L in Figure 1. This flue K at its.
opening to the external atmosphere must be stopped close when at work, the
only object of this opening being to clean it out when requisite. From the
above description it is plain that when the furnace is heated to the proper degree
of temperature for decomposing the coal in the retorts, the atmospheric air
admitted at the first openings H, H, will, when it reaches the upper air flue
K, K, be greatly heated before it is introduced into the furnace by the
openings L, L. The quantity of air admitted into the air flues can be regu-
lated by registers or regulators fixed at the entrance air flues H, H; and in all
cases the entrance air flues H, H, must be of such a length and so far exposed
to the heat of the furnace that it shall, before entering the furnace of the
openings L, L, be raised to a high degree of temperature, say about equal to
700° of Fahrenheit, but of course the hotter it is the better.
This arrangement of flues will be found to effect the ignition herein-before
mentioned as one object of this part of my said Invention; and the following
arrangement of apparatus, described in Figure 4, will shew the mode of making
sulphurous acid at the same time in Figure 4. A and B is a flue supposed to
lead at the end A from the retort furnace shewn in Figure 2 to a chimney at
the end B. C is a stop valve in the flue to check and divert the current of the
vapours or products of combustion passing from the furnace into and through
the condenser D, G, F, E. H, H, are two stop cocks to draw off the
sulphurous acid which under this arrangement will be deposited from the
vapours or products of combustion in the condenser, and which. sulphurous

page_text: acid will thus run into the receivers J, J. K is a small pipe for the admission
of steam into the condenser at D, which will assist in the condensation of the
sulphurous acid.
Secondly, as regards my improved mode of working off the charge,. I
make use of retorts about twice as long as those commonly used in coal gas
works; and I prefer them made of wrought iron, about half an inch in thick-
ness, and that the transverse sections of the retorts should represent the forms
shewn in the Drawing, Fig. 2, A, A, A. The retorts are open at each end,
and have a mouth-piece attached to each by the usual means. These mouth-
pieces are each fitted up with stand pipes, to which are fitted as usual bridge
pipes, dip pipes, and hydraulic mains, care being taken only that one of the
dip pipes B 1 does not seal or dip into the tar or liquid of the hydraulic main
so far as does the dip pipe B 2. And this shorter dip pipe is furnished with a
cup, valve, or stop cock M, capable of so closing this dip pipe by means of the
lever N, as to force the gas when required to escape out at the dip pipe B 2.
Any number of retorts found most convenient may be set up in one oven or
furnace to constitute a setting of retorts; but I prefer three, as shewn in the
Drawing accompanying these Presents.
+
I will now describe the mode of operating with retorts so arranged as
aforesaid. Instead of putting the whole charge of coals in at one time,
and taking off the gas at one end or mouth-piece only of the retort,. my plan
is as follows: Supposing the retort 1 A, A 2, to be empty, I charge only
one half of its length or thereabouts, say from 1 A to a, and leave the valve M
down or open, as shewn in the Figure, in order that the gas may pass out
at B 1 and receive the additional heat of the remaining or empty part of the
retort. It will be seen that the gas must necessarily take this course, because
the seal B1 is not so deep as the seal B 2. When in this position (sup.
posing the charge to be an eight-hour charge), then, at the expiration of four
hours, the end A 2 of the retort should be opened, and the empty half of the
retort from A 2 to a should be charged with coal and closed as usual. The
lever N should then be acted upon so as to draw up the cup valve M close to
the mouth of the dip pipe B 1, which cup being deeper than the seal at B 2
will stop the gas from continuing its course out at B 1, and oblige it to pass
out at B 2, thus compelling the gas evolved from the fresh portion of coal to
traverse over and through that portion which was first put into the retort,
whereby a combination is effected between the gas arising from each portion.
At the expiration of eight hours from the commencement of the operation the
lid 1A of the retort is taken off, and that part of the charge between 1 A and.
a, which we must imagine to be now clearly exhausted of its gas, is to be

page_text: drawn or cleared out, and a fresli charge of coal put in and the lid replaced;
at the same time the cup or valve attached to the dip pipe B 1, which was
before lifted up or closed, must now be lowered or opened into its original
position, in order to make the gas escape at B 1, thus causing the gas from
the fresh charge of coals to traverse between it and A 2 in like manner as
it formerly traversed between a and 1 A, and with the like effects. These
alternate operations are continued every four hours, and, therefore, I call my
retort so arranged a reciprocating retort. By this routine the gas and vapours of
the earlier hours of the charge will combine and mix with those producing from
the latter hours, whereby much more and better gas is produced than by any
process now adopted, whilst the quantity of coal tar and of ammoniacal liquor
usually formed are both much reduced. If it should be desirable to make
gas from coal tar with these retorts, I introduce an iron pan containing tar
into the mouth-piece of each retort at the time of its charging with coal.
And it is only necessary further to observe, that if the charge be a six-hour
charge, the alternating will be every three hours, and so on in proportion to
the duration of the charge.
Thirdly, as regards my improved method of rendering gas produced from
coal more free from ammonia and its combinations with sulphuretted hydrogen
and other impuritics than heretofore, I cause a pipe from a steam boiler to
deliver its steam below the surface of either sulphurous or muriatic acid con-
tained in any suitable covered vessel, partly filled only, and connected by a
pipe from its top to that part of the gas apparatus called the condenser or
refrigerator. When the vessel and its contents shall have attained a boiling
temperature, the steam will then pass on, carrying with it in solution the
vapours of the acid; and this mixture of steam and acid I introduce into
the coal gas as it leaves the condenser. The quantity of acid and steam
to be introduced into the coal gas will wholly depend upon the quality
or nature of the coal from which the gas is obtained; it is therefore im-
possible to state any exact quantity of acid that may be in each case
requisite, the object in all cases being to perfectly neutralize the ammonia
by the acid; and the best indication whether enough or two much has
been introduced is, from the effect the gas has upon the usual chemical
tests applied for indicating the presence of acids or of ammonia. In order to
insure plenty of steam, and at the same time avoid waste of acid by admitting
too much steam, the proper quantity to be introduced to the acid vessels may
be regulated a valve or stop cock. The proportion of steam required
should not be much less than what will produce when again condensed about
one imperial gallon for one thousand cubic feet of gas, which has been sub-

page_text: mitted to the foregoing process. I also cause a plate of sheet iron, covered
about half an inch deep with potash, to be placed on the surface of the coal
in the retort at the time of charging, and left there till the charge be with-
drawn, which will be found still further to purify the gas.
Fourthly, as to the new apparatus herein-before mentioned to be applied to
retorts, coke ovens, or furnaces of gas works, it is as follows, reference being
had to the Figure 3 in the Drawing annexed-A is a cylinder of wrought or
cast iron, and must be made of such dimensions that when lined internally
from top to bottom with fire bricks it shall be fully able to contain the charge
or quantity of coke about to be drawn from the retorts, coke ovens, or
furnaces adjacent to which such cylinder is placed. B is a grating or set of
fire bars near the bottom of the cylinder for the purpose of increasing or
keeping up the heat of the coke, as herein-after described. C is a lid or cover
fastened up against the bottom of the cylinder in the ordinary mode of fastening
the lids of retorts to prevent the access of air to the grate or fire bars when
necessary. D is a similar lid at the upper part of the cylinder. E is an
induction pipe for whatever matter may be introduced for the purpose of
generating gas; and F is an eduction or exit pipe for the said gas to pass out
to a condenser or other apparatus. The pipe F, it will be seen by the dotted
lines, may be a three-branch pipe, the utility of which will be described here-
after. G is a hopper or feeder supposed in this Figure to be placed under the
floor of the retort house, and in front of a bench of retorts, so as to receive
the coke when drawn from the retorts and conduct it into the cylinder A; but
this hopper G forms no part of my new apparatus.
Having now described the said new apparatus, I will proceed to explain
the manner of using the same:-Having removed the lids C and D, I fill the
cylinder A with hot coke from the retorts through the hopper G; the lid C
being off, the atmospheric air will rush up the cylinder and greatly increase
the temperature of the coke; and the nearer this heat approaches a white heat
the better. When the greatest possible heat is obtained by this means, or
when the upper portion of coke has attained a bright red heat, close both the
lids C and D, and turn on the steam or other matter to be introduced thro
the pipe E. This will, of course, cause gas to be generated, which will be
passed off at the pipe F. If the gas made in this manner be produced from
steam, it is evident that it will not pass off from the cylinder A in a state fit
for illumination, but must be subsequently submitted to the known process of
saturation with the vapour of essential oil, or other similar illuminating matter,
in order to render it for use. The advantage of making the pipe F a three-
branch pipe would be to prevent an useless expenditure of beat by opening

page_text: the upper branch first; and when gas ceases to be produced from the upper
portion of the coke, then, by opening the next branch below, and so on to the
lowest branch, stopping the upper ones as those below are opened.
Now, whereas as regards the first part of my said Invention, I do not claim
the introduction of heated air over or on the surface of the fuel of furnaces
generally, but only its application to furnaces of gas works where lime, dreg
water, ammoniacal liquor, or sulphuretted hydrogen gas are evaporated or
introduced under their bars, and also its application for the purpose of uniting
the said heated air with, and thus igniting the sulphuretted hydrogen gas and
the gases and vapours arising from the said lime, dreg water, and ammoniacal
liquor, whereby I prevent the escape of a large portion of sulphuretted
hydrogen gas, which otherwise passes up the chimney into the atmosphere, to
the annoyance of the neighbourhood.
And further, I claim the manufacture at the same time by this means of
the sulphurous acid required for carrying into effect the third part of my said
Invention.
And whereas, as regards the second part of my said Invention, I do not
claim the particular mode herein-before specified of causing the reciprocating
action of the gas by dip pipes and hydraulic mains and valves, because the
same effect may be obtained by other means or apparatus; but whereas I
claim as my Invention the mode of charging the retorts herein-before described
and causing a mixture and combination of the gases evolving from alternate
charges in the same retort by the application of an exit gas pipe at each end of
the retort, and also causing the gas to pass off alternatly at each pipe by
some such appropriate apparatus as that described at Figure 1.
And whereas, as regards the third part of my said Invention, I claim the
combination of steam with sulphurous acid or steam with muriatic acid applied
to coal gas, and the introduction of potash in the retorts, as herein-before
described for the purpose aforesaid.
And whereas, as regards the fourth part of my said Invention, I claim the
apparatus herein-before described at Figure 3, for the purpose herein-before
mentioned, and such my Invention described as consisting of four parts being,
to the best of my knowledge and belief, entirely new and never before used in
that part of His said Majesty's United Kingdom of Great Britain called Eng-
land His Dominion of Wales, or Town of Berwick-upon Tweed, I do hereby
declare this to be my Specification of my said Invention, and that I do verily
believe this my said Specification doth comply in all respects, fully and without
disguise, with the proviso in the said herein-before in part recited Letters

page_text: Patent contained, wherefore I do hereby claim to maintain exclusive right and
privilege to my said Invention.
band
In witness whereof, I, the said George Lowe, have hereunto set my
and seal, this Twelfth day of April, in the year of our Lord One
thousand eight hundred and thirty-two.