Improvements in Processes and Apparatus for Manufacturing .Heating Gas
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
"Improvements in Processes and Apparatus for Manufacturing
.Heating Gas."
ROBERT THOMSON, 21 Bothwell Street, Glasgow, Architect do hereby declare
the nature of this invention to be as follows:-
This invention relates to improvements in the design, construction and working,
of that class of gas-producers arranged to facilitate the recovery of bye-products,
by the separate delivery of different classes of gases, and to an improved process
for the conversion of fuel from the solid to the gaseous state, the object of which
is the simultaneous and continuous production of ammonia and gas from bitu-
minous or other coal, coke, shale, peat, or other nitrogenous fuel in such a manner
as to secure in a comparatively small portion of the total volume of gas produced,
a high percentage of the total nitrogen of such fuel in the form of ammonia, so
that only such small portion of gas requires to be treated for recovery of the
bye-products, and at the same time produce a gas, of high quality suitable for
use in internal combustion motors, and adapted for metallurgical and other
purposes.
The forms of gas-producers utilising bituminous coal hitherto in use in con-
junction with bye-products recovery plant while producing a gas which when
washed is suitable for gas engine use, necessitate the treatment of the whole of the
gas produced for the recovery of the bye-products. This requires a very cumbrous
and costly series of apparatus and very nice manipulation, and has the further
working cold" in order that the yield of
disadvantage that it necessitates
ammonia be sufficient to make the cost of recovery remunerative. This "working
cold" has as a consequence the still further disadvantage of producing a gas high
in carbonic acid which reduces its value as a source of heat and power.
To avoid these disadvantages it has often been proposed to split up the produce
into two distinct qualities of gas-rich gas and poor gas-by employing a
producer having two chambers or regions of production, and subjecting the fuel
to a preliminary coking or distillation process in the upper chamber under such
conditions in the presence of steam as to secure in the rich gases evolved therein
the bye-products desired to be recovered so that only this small volume of rich
gas requires to be treated for recovery of the ammonia; the resulting coke
passing direct from the upper or distillation chamber into the lower chamber or
producer proper where it is converted into poor or producer gas.
Now although this scheme of splitting up the gases into two distinct qualities
is theoretically correct the means which have hitherto been adopted for putting
it into practical operation have not been entirely successful, in respect that the
production of ammonia secured for after recovery in the rich gases represents but
a small percentage of the total nitrogen of the fuel and falls short of the recovery
which my invention is designed to effect.
This failure to secure the desired high percentage of ammonia in the rich gases
of distillation is partly due to the defective processes employed partly to the
insufficiency of the apparatus used and partly to the absence of any accurate
means of proportioning measuring and controlling the injection of steam and air,
to, and withdrawing and expelling the products from, the respective regions of

page_text: production, (the rich gas and the poor gas regions) the result being that the
product is irregular in quantity and quality, the conditions necessary to the perfect
action of the different producing processes not being under sufficient control.
By means of my invention hereinafter described I am enabled to overcome these
dithculties. The first part of my invention consists of an improved process for
the simultaneous manufacture of gas and ammonia from nitrogeneous fuel.
Another part of my invention consists of an improved arrangement of gas-pro-
ducers. My invention also comprises the combination with producers delivering
different classes of gases of mechanical appliances such as will enable me to
secure and maintain perfect control of the various operations therein conducted so
as to obtain the necessary regularity-in the quantity and quality of the products.
The first part of my invention relates to a process for the simultaneous and
continuous production of ammonia and gas from bituminous or other coal coke
shale peat or other nitrogeneous fuel. According to my process the fuel is sub-
jected during the course of its conversion from the solid to the gaseous state to
three successive operations at different temperatures and under different conditions
each being conducted in its appropriate region in a suitably designed and con-
structed gas-producer in which the fuel passes automatically downward. These
operations are so conjoined as to constitute a continuous process in which ammonia
is formed and different classes of gases are separately, but simultaneously
produced in one apparatus. In the first of these operations the fuel undergoes
partial distillation without access of air the evolved gases passing downwards. The
resulting coke instead of as heretofore passing direct from the distillation region
into the combustion region is by my process subjected to a second retorting opera-
tion during which it undergoes prolonged treatment within suitable temperature
ranges in a rising blast of hot producer-gas in the presence of steam for the
elimination of nitrogen and the formation of ammonia. Thereafter the coke
freed of this nitrogen passes from this and undergoes a third operation in which
it is subjected to a blast of mingled air and steam, thereby effecting its partial
combustion.
While the formation of ammonia is facilitated by the decomposition of steam
the hydrogen of which combines with the nitrogen of the fuel its preservation
when formed is ensured by the presence of uncombined steam so that steam is for
that purpose delivered in excess of the quantity indicated as necessary by the
laws of chemical combination the uncombined steam being condensed in the
subsequent recovery process by which the tar and ammonia are separated. To
enable me to efficiently conduct the various operations required to carry out my
process so as to economically attain the desired results the gas-producer con-
structed according to this, another part of my invention, provides for the addition
of an intermediate chamber in which the coke may be treated with steam for
elimination of its nitrogen and this chamber I interpose between the retort like
upper chamber and the combustion chamber of existing types of producers. My
producer therefore consists of three conjoined chambers, preferably of unequal
diameters superposed and having between each pair suitable provision for the
separate withdrawal of the gaseous products. These three chambers open fully
into each other and when charged contain together but a single body of fuel. The
exits provide for the escape of the gases from the fuel being maintained constant
at two different levels which may be adjusted relatively to each other to suit the
class of fuel undergoing treatment. The two upper chambers are preferably
surrounded by the issuing hot producer-gas from the lower chamber.
The upper chamber which may be constructed of cast-iron is furnished with
the usual valve and hopper arrangement or other device for feeding in the raw
fuel which is during its downward passage through this chamber dried and
partially distilled without access of air the evolved gases being withdrawn down-
wards into the underlying hotter region in order that the bulk of the tars may
be destroyed and converted into fixed gas and that any tars remaining may leave
the producer at such a temperature as will prevent their condensation until they

page_text: each the recovery plant.
This distillation chamber serves, to regulate any
rregularity of feeding and being made less in diameter than the underlying
ntermediate or ammonia chamber the space between these two serves for the
escape and withdrawal of the rich ammonia charged gases. This difference in
liameter allows for further swelling of the fuel when in contact with the rising
hot gases and by changing the speed of the fuel feeding down breaks up and
lossens the mass, facilitating thereby the permeation of the fuel by the rising
liot gases and introduced steam as well as facilitating the emission of the gases
evolved therein. The emission and withdrawal of these ammonia charged gaseous
products takes place in the interval between the two upper chambers.
The coke resulting from distillation passes into the intermediate chamber which
is preferably constructed of cast steel. In this chamber or region the coke as it
passes downwards is subjected to a much higher and gradually increasing tem-
Part of this steam being decomposed by
perature in the presence of steam.
contact with the hot fuel the nascent hydrogen thereof combines with the nitrogen
of the fuel to form ammonia. The heat in this chamber is principally furnished
by a portion of the hot producer-gas drawn from the underlying combustion
chamber. This hot gas and the introduced steam together traverse the fuel in this
intermediate or ammonia region and are with the undecomposed portion of the
steam and the rich gases and other products of distillation evolved in this and the
upper chamber all withdrawn by the one exit and together pass to the recovery
plant to be there treated for separation of the gas and bye-products. The more
nearly the speed of feeding down of the fuel in the ammonia region approximates
to the speed of feeding down in the combustion region the longer the time during
which the coke will be under treatment for elimination of its nitrogen and
consequently the higher will be the percentage of ammonia formed and made
available for recovery. To this end the area of the ammonia chamber relatively
to that of the combustion chamber should be as large as possible consistent with
due provision for the escape of the producer gas from the underlying combustion
region.
Between the middle or ammonia chamber and the lower or combustion chamber
there is another interval where a sudden change of section also takes place. This
again effects a change in the speed of the fuel feeding down and as a consequence
again breaks up the fuel as it enters the lower chamber or producer proper thereby
further loosening the mass and facilitating the emission of the producer gases
therefrom. The fixed carbon of the fuel remaining from the intermediate or
ammonia region sinks therefrom into the lower or combustion chamber or pro-
ducer proper. Herein it is subjected to a blast of air mingled with steam both
accurately measured and properly proportioned to each other, and to the incan-
O descent body of fuel undergoing treatment therein. This body of fuel I maintain
of sufficient depth and temperature to decompose the introduced steam and
convert the generated carbonic acid to carbonic oxide. The level of the exit for
the escape of the gas being constant the depth of the incandescent fuel body may
be regulated by the amount of ash withdrawn.
15
50
.
The steam necessary for effecting the production of ammonia preferably super-
heated may be admitted by means of a pipe passing centrally downward from
above. The discharge of this pipe is capable of vertical adjustment so that the
steam may be delivered at such a level as to traverse as fully as possible the coke
undergoing treatment for the formation of ammonia.
In order to assist in securing greater regularity of working and to improve
the results obtainable by that class of gas-producer designed to deliver separately
different classes of gases another part of my invention comprises the combination
with such producers of mechanical appliances by means of which the injection
of steam and mingled air and steam into the producer and the withdrawal and
55 expulsion of the gaseous products therefrom may be controlled and maintained
in correct proportion to each other and to the weight and class of fuel being
operated on so that I am able by regulating the respective volumes of air an

page_text: steam introduced and the gaseous products withdrawn and expelled to maintain
each portion of the fuel body while undergoing treatment at such temperature
and under such conditions as may be best suited to secure a high percentage of
nitrogen as ammonia in a comparatively small volume of gas and at the same
time produce a gas of good quality suited for use in gas engines and adapted for
metallurgical and other purposes.
The different classes of gases may be collected and used separately or the rich
gas when deprived of its ammonia can be restored to the producer being injected
into the combustion region enriching the producer gas with its hydro-carburets
which are converted into non-condensible gases by contact with the incandescent
coke through which it passes.
The tars recovered may also in like manner be restored to the producer and
passed through the incandescent coke in the combustion chamber thereof and
converted into non-condensible gases while traversing the incandescent coke.
By the combination of the two classes of gases and the restoration and gasifica-
tion of the tars a complete producer gas containing all the original elements is
obtained thereby rendering it fit for many purposes for which ordinary washed
gases are inapplicable.
Dated this Eighth dox of December 1800.
QUALL 171 1701 PITIATION.
66 Improvements in Processes and Apparatus for Manufacturing
Heating Gas "
I, ROBERT THOMSON, of 21, Bothwell Street, Glasgow, Scotland, Architect. 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;-
This invention relates to an improved process for the simultaneous and con-
tinuous production of gas and ammonia from fuel during its conversion from
the solid to the gaseous state, and to a new type of gas producer and arrangement
of apparatus in connection therewith for effecting such process, the object of the
invention being to so effect the process of gasifying bituminous or other coal,
coke, shale, peat, or other suitable fuel, as to generate therefrom a non-condensible
producer gas, practically free from tar and water vapour, which is suited for use
in gas engines and for industrial heating purposes generally; and to so conduct
the process of gasification as to facilitate the recovery of bye-products by securing
the volatile constituents of the fuel and a high percentage of its total nitrogeneous
contents as ammonia in a comparatively small portion of the total volume of gas
produced, so that only such small portion of gas requires to be treated for
recovery of the bye-products.
When using bituminous fuel great difficulties arise, in single chamber producers
as hitherto generally constructed and worked, from the caking of the fuel and
the consequent formation of holes or channels in the fuel body. This trouble
necessitates frequent pokering, which however at the best is very ineffective and
does not remove, but merely mitigates, the evil. The production of gas from
bituminous fuel in such producers is very irregular, both in quantity and quality,
and they neither produce gas free from tar, nor yet do they yield sufficient tar
and ammonia to make the recovery of these profitable, and the produced gas has
the further disadvantage that it is burdened with the vapour of the water which
the fuel may have contained. Where, however, recovery of ammonia
and other bye-products is desired, the yield of ammonia is increased

page_text: passing volumes of steam through the burning fuel in excess of its decom-
sing power, so as to cause the producer to work cool enough to preserve the
mmonia, when formed, from dissociation; but this method of working interferes
ith the conversion of the generated carbonic acid to carbonic oxide, and thus
egrades the quality of the resulting gas by making it rich in carbonic acid.
urther, this process necessitates the treatment of the whole volume of gas
roduced for recovery of the ammonia and other products, and this involves the
se of a very large and expensive plant.
In the hope of obviating these difficulties gas producers have been constructed
aving two chambers or regions of production, one above the other, each having
ts own gas delivery, the gas from the upper chamber alone being treated for
ecovery of the bye-products, and the fuel from the upper chamber being treated
n the lower chamber for the production of producer, or poor gas. In such
producers the steam employed to increase the yield of ammonia, instead of being
ntroduced into and passing through the fuel in the combustion region, as before,
has been introduced near the bottom of the distillation chamber with the view
to its passing through the fuel therein only, and being led off with the small
volume of rich gas. The steam so introduced however soon cools down the fuel
in the retort, and thus interferes with the process of distillation. This method
of working permits of part of the steam and some of the hydrocarbon passing
into the poor gas, thus charging the latter with condensible gases and water
vapour, and causing a decrease of the yield of bye-products.
In such producers the poor gas is passed off between the upper and lower
regions, and the rich gas withdrawn upwardly through the body of fuel in the
retort, the result being that the product from both regions is irregular in quantity
and quality.
While this scheme of splitting up the gases into two different grades is theoreti-
cally correct, the means which have hitherto been adopted for putting it into
practical operation have not been successful in securing either a poor gas free
from tars and water vapour, or a rich gas containing the desired high percentage
of ammonia and other products.
The principal reason for this unsatisfactory result is that the two chambers or
regions of gas production hitherto provided permit of, and practically necessitate
the two operations merging into each other, the upper passing into the lower, the
single upper region, even when steam is not admitted, being insufficient to afford
passes into the combustion region,
the complete distillation of the fuel before
which is essential in order to secure, in the rich gases of distillation, the whole
of the volatile constituents of the fuel, so as to obtain an absolutely clean, non-
condensible producer gas from the resulting coke.
In order to obviate the disadvantages arising from the introduction of the
steam employed for the formation and preservation of ammonia into either the
lower chamber, where it interferes with, the process of gasification, or into the
upper chamber, where it interferes with the process of distillation, and to provide
that the volatile constituents of the fuel and a high percentage of the total
nitrogeneous contents thereof, as ammonia, may be obtained in a small portion
of the total gases produced, and that no incompletely distilled fuel may enter
the lower, or combustion, chamber, to interfere with the production of a non-
condensible producer gas therein, and further, that the production of gas in the
upper region may be undisturbed by the feeding in of fresh fuel, I rearrange the
Oposition of the gas exits hitherto provided, utilising that previously used for the
emission of the poor gas for the withdrawal of the rich gases, and providing for
the emission of the poor gas being effected, not at the bottom of the retort-like
upper region as before, but at a lower level, sufficiently removed therefrom to
allow of an additional region being obtained, so that I may completely separate
5 the upper and lower chambers, or regions of gas production, by interposing
between them an intermediate chamber or region, in which complete distillation
of the partly distilled fuel on its way from the upper to the lower chamber may

page_text: be effected, and in which it may be subjected to the action of the steam for the
purpose of increasing the yield of ammonia, without such steam interfering with
either the process of distillation, or gasification, conducted' in the upper and
lower chambers respectively.
My invention consists therefore in treating the fuel by three successive opera-
tions, and in forming the producer with three main regions of gas production,
situate in three superimposed chambers, the lower portions of the fuel in the
upper and middle regions depending into the fuel in the upper part of the under-
lying chambers, the upper chamber being externally heated, and acting as a
distilling chamber, the intermediate chamber supplied with fuel from the upper,
the fuel being therein completely distilled for bye-products and, when desired,
acted on by steam, for the formation and preservation of ammonia, the lower
chamber supplied with the fuel from the intermediate chamber, and having air.
or steam and air passed into it for the formation of poor or producer gas. At
the junction of the upper and intermediate chambers conduit is provided for
the withdrawal of the rich gas, and at the junction of the intermediate and lower
chambers provision is made for the discharge of the poor or producer gas.
Referring now to the accompanying drawings, which illustrate a wet bottom
producer constructed according to my invention:
bue.
Figure 1 is a sectional elevation of the producer on the lines A, B, C, of
Figure 2. Fuel is only shewn in the left hand half, so that the construction
may be indicated clearly in the other half.
Figures 2 and 3 are sectional plans on the lines D, E, and F, G, Figure 1.
Figure 4 is a sectional plan on the lines H, K, L, M, Figure 1.
Figure 5 is a diagrammatic elevation, illustrating on the right hand side the
arrangements for drawing off the rich gases from the producer, and for passing
them through the apparatus for cooling and extracting the bye-products, and on
the left hand side the arrangements for drawing off the poor gas for cooling and
extracting the dust therefrom.
Figure 6 is a diagrammatic elevation, illustrating the arrangement for drawing
the rich gases of distillation from the upper and middle regions, and introducing
them to the lower region, in order that any unstable gases may be fixed by contact
with the incandescent fuel therein, and passed off, mingled with the poor gases
therefrom.
Figure 7 shows a modified form of steam admission pipes. In this arrangement
the position of the superheated steam nozzle 5 can be regulated by raising or
lowering the pipe g to obtain the best results. The level of the delivery nozzle
of pipe may also be adjusted if desired.
In the producer the upper region may be formed in one, two, three or more
chambers or retorts b, b, b, as shewn in the plans Figures 2 and 3 all increasing
in diameter towards their lower ends, and fed from the hoppers a, a, a, which
in turn are fed from a fuel bin 1, having three holes 2, adapted to be closed by
plates 3.
The feed hoppers are exposed to the atmosphere while the retorts bare
enclosed and externally heated by the poor or producer gases in their exit. The
intermediate chamber with which the lower ends of the retorts b connect, has
at its top a metal casing which, with the pipe e, serves to draw off the rich
gases containing all the volatile matter, and the ammonia and other bye-products
produced from the fuel, and the undecomposed portion of the steam introduced
by nozzle 4. The pipe is used to introduce a sufficient quantity of preferably
highly superheated steam, for decomposition into the hot region just below the
chamber c, and within range of the exhauster ic; and the pipe f carries preferably
ordinary or wet steam to cool down the fuel and regulate the temperature in c,
enabling the ammonia just formed from the decomposed steam to exist. The
lower chamber or region his formed of the usual brickwork i, supported by
suitable brackets j on a sunk foundation k, and has a water seal ring /.

page_text: The chamber may be larger than the chamber c, the walls of c being formen
f a series of flued bricks, m which support the annular conduit d.
At the bottom of the chamber ha conical capped steam and air inlet n is
rovided, to convey the steam from the pipe o, and the air from the pipe p, into
he producer, and to deflect the fuel to the sides of the producer bottom in the
isual well known manner. I prefer that the steam pipe o should not enter the air
pipe till close under the conical inlet, although it is shewn inside the air pipe P
for the sake of clearness. The flued bricks m above referred to conduct the
producer or poor gas into the upper part of the producer casing whence they
pass by the opening (Figures 1 and 2) to the exit pipe s, being thus caused to
heat the chambers on their way. A pipe u and inlets t may be provided so that
the rich gases passing out from e, when not treated for the recovery of the bye-
products, may be passed through the incandescent fuel in the chamber 4, and be
thus thoroughly cracked and converted into fixed gases, which would then pass off
This arrangement is shewn
with the producer or poor gases by the pipe s.
separately in another view, Figure 6.
The gases passing out by the pipe e may be drawn through a condensing plant
for the separation of ammonia and other bye-products, as illustrated diagram-
matically in Figure 5, where the pipe e is shewn connected to a scrubber or
condensing apparatus, through which the gases are drawn by an exhauster w.
Similarly the gases passing out by the pipes may be drawn by an exhauster a
through a cooling coil y and a dust filter.
The upper
chambers or retorts a, b, by being made less in total area or diameter
into which they
or chamber 0,
than the underlying middle region
deliver the partially distilled fuel, effect a change in the speed of the fuel feeding
downwards, as it enters c; this change breaks up and loosens the mass, and
assists thereby the permeation of the fuel by the hot gases, and by the steam
introduced for the purpose of increasing the yield of ammonia, and also facilitates
the emission of the gases evolved in the middle region c. Although the feed to
the hoppers a may be intermittent, by maintaining a head of fuel in the hoppers,
the feed to the producer is continuous and regular. This constant feed results in
a gas production undisturbed by the usual fluctuations arising from intermittent
feeding. The fuel in the hoppers a forms a continuous body with the fuel con-
tained in the producer, and undergoing distillation, and thus avoids the usual
drop between the fuel inlet and the surface of the fuel body in the producer,
thereby preventing caking, and so obviating the difficulties which arise from
the caking of the upper surface of the fuel. The depth of the fuel body in the
hoppers and in the retort region b, by preventing the ingress of any considerable
amount of air, enable the feed hoppers a to be charged, without the intervention
0 of the usual valves, direct from the overhead fuel-bin 1, the deliveries of which
are just sufficient above the mouths of the hoppers to admit of the insertion of
cover plates 3, which serve to close both the feeding mouths 2 of the fuel bin 1
and the hoppers a simultaneously. The deep column of fuel maintained in the
producer, secures by constant pressure, the advantage of a compact body of fuel
5 in the combustion region, which is of special value in the case of peat fuel.
The fuel in the process of its conversion from the solid to the gaseous state is
thus, in accordance with my invention, subjected to three principal successive
operations, each of which differs from the others, and is conducted in its appro-
priate region. These operations are so controlled and conjoined, as to constitute
50 a continuous process, during which ammonia and other products are formed, and
different grades of gas simultaneously produced in, and delivered separately from
one apparatus. In the first of these operations, conducted in the upper region
of the producer, the fuel is dried, and undergoes partial distillation for elimination
of the more volatile hydrocarbons without access of air. The heat required, which
55 is supplied externally and in the producer shown in the drawings, is obtained
from the circulation of the hot gases from the lower region h, on their way to
the exit pipe s. In the second operation conducted in the middle region of the

page_text: producer practically complete distillation of the partially coked fuel from the
upper region is effected under the action of heat directly applied internally; and
when the formation of ammonia is desired, distillation in this region is conducted
in an atmosphere of steam, this steam being introduced in such a manner as to
permeate the fuel contained therein, the object being to secure the elimination
of the nitrogen of the fuel for the formation of ammonia, and the preservation
of such ammonia when formed. While I may introduce but one supply, of steam,
and employ but one nozzle for this purpose, in order that the steam required for
the preservation may not interfere with the action of the steam employed for the
formation of ammonia, I prefer to introduce separate supplies at different levels.
In this way I am enabled to introduce each supply in the condition best suited
for the duty to be performed; for instance, in order that the fuel may decompose
as much steam as possible for the formation of ammonia, I prefer that the steam
for this purpose be highly superheated, while that for the preservation of the
ammonia formed I prefer to be ordinary or saturated steam. The respective steam
supplies may be introduced by nozzles 4 and 5 shewn in Figure 1.
Part of the steam, i.e. that supplied through the pipe and lower nozzle 5,
which is preferably highly superheated, is decomposed; the nascent hydrogen
The other
thereof uniting with the nitrogen of the fuel to form ammonia.
part, i.e. that passing through pipe and upper nozzle piece 4 is preferably not
superheated, and serves to cool the fuel sufficiently to protect the ammonia when
formed.
The heat required in the middle region is directly supplied by the incandescent
body of fuel in the lower region of the producer, partly by conduction and partly
This heat
by hot gases withdrawn therefrom by the action of the exhauster w.
may be regulated and controlled so as to secure the highest possible production
of ammonia. The gases evolved in the upper and middle regions, together with
the portion of the hot gases drawn from the lower regions, and the undecomposed
portion of the steam introduced into the middle region, are withdrawn by means
of an exhauster w by way of the exits d, e, between the upper and middle
regions, and through the condensing plant (Figure 5) where they are treated
The non-
for separation of the steam and extraction of the bye-products.
condensible gases from the lower region are discharged by way of the exits 6 in
the bricks m between the lower and middle regions in a condition fit for immediate
use in furnaces. Their discharge may be assisted by means of an exhauster .
which draws them, when required for engine purposes, through the usual cooling
pipes and dust filters y. The more nearly the speed of feeding down of the fuel
in the middle region approximates to the speed of feeding down in the lower
region, the longer the time during which the coke in the middle rerion will be
under treatment for elimination of its available nitrogen, and consequently the
higher should be the percentage of ammonia formed for recovery. To this end
therefore I arrange for the area of the middle chamber or region being made as
nearly equal to that of the lower chamber or region, as possible, consistent with
due provision for the escape of the producer gas from the lower or combustion
region.
Between the middle chamber and the lower or combustion chamber, where the
bricks m, m, provide for the escape of the gases from the lower region, a sudden
change of section may also take place as shewn. This again effects a change in
the speed of feeding down, and as a consequence again breaks up the fuel as it
enters the lower chamber or producer proper, thereby further loosening the mass,
and facilitating the emission of the producer gases therefrom. In the third
operation, conducted in the lower region of the producer, the completely distilled
fuel from the middle region is subjected to a blast of mingled air and steam from
below by the pipes and p. The steam being here decomposed, hydrogen is
thus liberated, a part of the fuel is oxidised, and the remainder converted to
carbonic oxide. The air and steam introduced into the combustion region are

page_text: oth properly proportioned to each other, and to the incandescent body of fuel
undergoing treatment therein.
of
to
the
20
This fuel body I maintain of sufficient depth and temperature to decompose
such introduced steam, and to convert the generated carbonic acid to carbonic
oxide. The level of the exit for the emission of the producer gas being constant,
the depth of the incandescent fuel body may be regulated by the amount of ash
withdrawn from the producer. I am able, by regulating the respective
volumes
steam introduced to the middle region, and mingled
and the
lower region,
gaseous
air and steam introduced
of the exhauster from the upper
products withdrawn by means
and middle regions, and expelled from the lower region by the blast of mingled
air and steam, or withdrawn by the exhauster x, to maintain each portion of the
fuel body, while undergoing treatment, at such temperatures, and under such
conditions, as are best suited to secure, together with other products; a high
percentage of nitrogen, as ammonia, in a comparatively small volume of gas, and
at the same time to produce a non-condensible gas of good quality, suited for
use in gas engines, and adapted for metallurgical and other purposes.
In some cases where it is not desired to recover bye-products, but simply to
produce a non-condensible gas, no steam is introduced to the middle region, and
the gases evolved in that and the upper region are together withdrawn by way
of the upper gas exit, and introduced to the producer by a pipe u and inlets t
so as to traverse the incandescent fuel body, during which the hydrocarbon gases
and water vapour are decomposed, so that they may leave the fuel, together with
the carbonic oxide, as non-condensible gases, by way of the lower gas exits 6.
In cases where it is desired to recover the bye-products, the gases evolved during
the first and second operations, together with the undecomposed steam and the
hot gases drawn from below are withdrawn, by way of the upper gas escape, by
The gases after
means of an exhauster, and are passed through condensing plant.
separation of the bye-products may be either conducted away for use alone, or
passed into the conduit s, and mixed with the poor gas.
The tars recovered may be restored to the producer and passed through the
incandescent coke in the lower region, and thereby converted to non-condensible
gases to be passed off with the poor gas; or part may be blown by way of the
dependent pipe, f, together with the steam, into the lower part of the middle
region. By the combination of the two grades of gases, and the gasification of
the tars, a complete producer gas containing most of the original elements of the
fuel in a non-condensible gaseous state, may be obtained, thereby rendering the
gas fit for many purposes for which ordinary washed gas is inapplicable.
Having now particularly described and ascertained the nature of my. said
invention and in what manner the same is to be performed, I declare that what
I claim is
(1) Treating bituminous fuel, peat or shale, for the production of a non-
condensible heating gas by a three stage but continuous process, comprising: (1)
a preliminary distillation operation under external heating; (2) a further distilla-
tion operation under the action of direct internal heating; (3) a combustion and
gasification operation on the distilled hot fuel under the action of air or steam
and air, substantially as described:
2. Treating bituminous fuel, peat or shale, for the production of a non-
condensible heating gas and recovering, together with other products, the nitrogen
0 in the fuel as ammonia by a three stage but continuous process comprising: (1)
a preliminary distillation operation under external heating; (2) a further distilla-
tion operation under direct internal heating in the presence of steam; (3) a
combustion and gasification operation on the produced hot fuel under action of
air, or steam and air, substantially as described.
5 3. A gas producer adapted to generate non-condensible gases from bituminous
coal and other similar fuel, and to secure for recovery in a small volume of gas

page_text: the available bye-products, comprising an upper chamber for preliminary distilla-
tion, an intermediate chamber for final distillation, to which steam is introduced
for the production and preservation of ammonia, and a lower chamber for com-
bustion and gasification of the fuel fed from the intermediate chamber, and having
a supply of air, or steam and air, introduced, substantially as described.
4. A gas producer adapted to generate non-condensible gases from bituminous
coal and other similar fuel, comprising an upper chamber for preliminary distilla-
tion; an intermediate chamber for final distillation, and a lower chamber having
provision for the introduction thereto of the distilled gases for combustion and
gasification under the action of steam and air, substantially as described.
5. In a gas producer, as claimed in Claim 4, passing the distilled gases from
the upper and intermediate regions into the lower or incandescent region of the
producer, thereby cracking and converting them to non-condensible gas which is
passed off with and serves to enrich the poor or producer gases proper, sub-
stantially as described.
6. In gas producers adapted to simultaneously produce gas and ammonia, the
employment at different levels, intermediate in the height of the fuel body of two
separate steam supplies, one for the formation, and the other for the preservation,
of ammonia, substantially as described.
7. In gas producers adapted to produce gas and ammonia, dependent and
concentric steam admission pipes, capable of vertical adjustment to deliver steam
at different levels, substantially as described.
8. In gas producers adapted to simultaneously produce gas and ammonia, the
employment of exits for the emission of gases at two different levels intermediate
in the height of the fuel body, the one for emission of the poor gas, and the other
for withdrawal of rich gas and bye-products, substantially as described.
9. In gas producers, a conical combined feed and distillation hopper heated at
one part externally by the poor gas from the producer, and giving a head of fuel
ensuring feed through the producer, so that periodic feed of fresh fuel takes place
on the unheated portion of the fuel in the producer, substantially as described.
10. The improved construction and arrangement of gas producer, substantially
as described, and illustrated in the accompanying drawings.
Dated this 9th day of September 1900.
MARKS & CLERK
18, Southampton Buildings, London, W.C.
13, Temple Street, Birmingham, and
25, Cross Street, Manchester, Agents.