Improved Method or Process for the Gasification of Fuels, and Apparatus therefor.
Year: 1890

page_text: Date of Application, 25'h Jan., 1890
Complete Specification Left, 24th Oct., 1090-Accepted, 29th Nov., 1890
PROVISIONAL SPECIFICATION.
Improved Method or Process for the Gasification of Fuels, and
Apparatus therefor.
A communication from ERNEST SOLVAY and LOUIS SEMET, both of 19, Rue du Prince
Albert, Brussels, Manufacturers.
I, WILLIAM LLOYD WISE, of No. 46 Lincoln's Inn Fields, in the County of
London, Consulting Engineer and Patent Agent, do hereby declare the nature of
this invention to be as follows:-
:-
It has long been known that by passing water vapour over fuel in a state of
incandescence, complete combustion of the fuel can be effected. The water vapour
becomes disassociated, and gases are formed consisting of hydrogen, carbonic oxide,
and carbonic acid. Water gas is produced in this way. But as this reaction requires
heat, the incandescence of the fuel diminishes, and the combustion gradually ceases if
no supplementary heat be provided to maintain the reaction. Usually this heat has
been provided by an indirect and supplementary heating of the apparatus containing
the fuel. This solution of the problem is not applicable to operations on a large scale,
as it is well known how difficult it is to cause heat at a high temperature to ponetrate
through walls ever of slight thickness, and particularly to the centre of the mass of
products to be heated. This system of heating tends rather to a multiplicity of
apparatus and it then loses the simplicity which is inseparable from manufacturing
operations on a commercial scale. On the other hand, if it be desired to supply the
process of combustion with steam with the necessary additional heat by means of the
steam itself, that is to say, by superheating the steam, a calculation will shew
that the temperature to which the steam should be raised, is incompatible with the
means at present known for this purpose.
In some systems for manufacturing water gas, the requisite heat is obtained by
causing the passage of steam to the fuel to take place alternately with the periods of
combustion by air. This intermittent working does not however offer a final solution
of the problem.
It is also known that a certain proportion of water vapour has been added to air
for combustion in gas generators, with the object of lowering the temperature of com-
bustion, and of regenerating a portion of the ammonia which is destroyed by
distillation at a high temperature, and also of having a certain proportion of hydrogen
in the gases, which allows of diminishing to some extent the loss of 30% which has
been inherent until now to this method of gasification of the fuel.
Now this invention relates to a method of converting all kinds of fuel into a gaseous
form by water vapour, the necessary additional heat being supplied by superheated
steam for the one part, and a small portion of air, also superheated, for the other part,
such superheating being preferably effected by the gas produced. By utilizing the
heat of the escaping gases for superheating the entering gases (water vapour and a
small fractional quantity of air), if the theoretical conditions of radiation equal to nil,
and of perfect regeneration of the heat of the escaping gases, could be realized, the
conversion of a solid fuel into a cold gaseous fuel having a calorific efficiency exactly
equal to that of the former, could be effected. It is true a part of the hydrogen will
be substituted for an equivalent quantity of carbon, but the same total amount of
utilizable units of heat will be obtained in the gas as in the original fuel. Moreover
there will be produced gases that are comparatively rich, and are capable of producing
the highest temperatures, whilst gas generators supplied with air alone produce gases
that are considerably diluted with nitrogen.
Since the gases produced according to this invention can be made of greater richness

page_text: the higher the temperature to which the steam is superheated, and correspondingly
reducing the amount of air for combustion, this superheating is effected not only by
contact with the escaping gases, but by the combustion of a small quantity of these
gases with the necessary quantity of air in an apparatus of the regenerator type,
preferably indirect, in which the necessary steam and supplementary air are super-
heated. The steam and air may be mixed, or be introduced separately, or a portion
of each may, if desired, be first sent into the ash pit of the apparatus, so as to become
heated by cooling the ashes.
In case it should become necessary to still further raise the temperature of the steam
and supplementary air, this can be effected (1) by causing the combustion of the
heating gases to take place under pressure, and (2) by superheating the gas and air to
be burned in the recuperator.
It will be noted that the heat thus diverted, and taken from a part of the gases
already produced, is only an advance made to the principal reaction, i.e. to the com-
bustion by steam, and will be found intact at the exit, as the entire process may be
considered as a cycle in which no loss of heat whatever takes place.
By superheating the water vapour, another advantage which has previously been
sought for, is obtained and which renders the improved process of still further value.
It has long been known that the distillation of coal under ordinary conditions
entails the loss in the inactive state of a considerable proportion of the contained
nitrogen, and of which only about the tenth part of the possible amount is recovered
in the form of ammonia. It has been proposed, in order to regenerate a portion of
this ammonia, to distil and burn the fuel at the lowest possible temperature, and with
this object, it has been proposed, as herein before mentioned, to add water vapour to
the air intended for combustion, but, as will he understood, without superheating such
water vapour. The opposite plan has also been adopted, viz., that of using water vapour
alone, indirectly superheated, and although the apparatus employed has not been suit-
able for operations on a large scale for the reasons hereinbefore mentioned, the yiel·l
of ammonia was considerably increased.
In the present process, on the contrary, the superheating of the steam and of the
supplementary air, is effected by an exchange of temperature with the escaping gases
of combustion and by the combustion of a portion of these gases in an apparatus
specially adapted for the purpose, and of the type of regenerator employed in glass
making and in metallurgy. The superheating is thus effected without additional cost,
and the small quantity of air mixed with the steam is not sufficient to check the
favourable part played by the steam in the production of ammonia, even at high
temperatures. Thus according to this invention solid fuels can be gasified into cold
rich gaseous products without any loss whatever due to the conversion, and without
cost, theoretically, for heating, whilst producing a high yield of ammonia.
Apparatus for carrying out the process may be of various forms. The chief feature
that distinguishes such apparatus from the ordinary gas generators, is the absence of
grates either horizontal or inclined, which are replaced by vertical walls along which
the oxidation takes place, and combination of such apparatus with the steam and air
superheating apparatus.
A cylindrical furnace without a grate, or cupola may be employed closed at top and
bottom, provision being made for charging the fuel (coke, coal, lignite, anthracite &c.)
into its top, and for allowing of the discharge of ashes at the bottom, by means of any
suitable automatic arrangement.
The steam and air necessary for the gasification are first caused to regenerate or absorb
the heat carried off by the gases of distillation and combustion, and are then passed
into what may be called the regenerator by analogy of construction with similar
apparatus used in other industrial processes but which have heretofore been employed
for a somewhat different object. This regenerator, preferably indirect, and of the
Ponsard, Lencauchy or other similar type, is arranged as near as possible to the
furnace or gas generator, it may be in the wall of the furnace itself, or even at the centre
of the gas generator which thus becomes annular. Through one of the conduits of
the regenerator steam and air are caused to circulate and through the other, a portion of

page_text: gas preferably taken from that produced in the generator, and previously washed to
remove ammonia therefrom. This gas mixed with the desired quantity of air for
burning the same (both being superlicated if required) serves to effect the superheating
of the steam and air to be gasified, which pass out of the lower part of the generator,
and up through the layer of fuel, burning the latter with formation of carbonic oxide
and hydrogen.
If desired, a regenerator of the Whitwell, Cooper, Siemens, or other similar type,
might be employed. It will be seen that the walls play the part of heating surfaces
and replace grates.
If there should remain a slight excess of heat in the escaping-gases, it can be
employed to generate the necessary steam.
Another arrangement of gas generator consists of a series of rectangular furnaces,
joined together by a wall as in Appold's coke ovens, the regenerators alternating with
the furnaces proper, or they may be situated externally, but very close to the wall.
The gases may be forced, or drawn, or impelled by steam by means of any suitable
apparatus such as a Körting apparatus.
Dated this 25th day of January 1890.
COMPLETE SPECIFICATION.
Improved Method or Process for the Gasification of Fuels, and
Apparatus therefor.
A communication from ERNEST SOLVAY and LOUIS SEMET, both of 19, Rue du Prince
Albert, Brussels, Manufacturers.
I, WILLIAM LLOYD WISE, of No. 46 Lincoln's Inn Fields, in the County of
London, Consulting Engineer and Patent Agent, 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 :-
It has long been known that by passing water vapour over fuel in a state of
incandescence complete combustion of the fuel can be effected. The water vapour
becomes disassociated, and gases are formed consisting of hydrogen, carbonic oxide,
and carbonic acid. Water gas is produced in this way. But as this reaction
requires heat, the incandescence of the fuel diminishes, and the combustion gradually
ceases, if no supplementary heat be provided to maintain the reaction. Usually
this heat has been provided by an indirect and supplementary heating of the
apparatus containing the fuel. This solution of the problem is not applicable to
operations on a large scale, as it is well known how difficult it is to cause heat at a
bigh temperature to penetrate through walls even of slight thickness, and particularly
to the centre of the mass of products to be heated. This system of heating tends
rather to a multiplicity of apparatus and it then loses the simplicity which is
inseparable from manufacturing operations on a commercial scale. On the other
hand, if it be desired to supply the process of combustion with steam with the
necessary additional heat by means of the steam itself, that is to say, by super-
heating the steam, a calculation will shew that the temperature to which the
steam should be raised, is incompatible with the means at present known for this
purpose.
In some systems for manufacturing water gas, the requisite heat is obtained by
causing the passage of steam to the fuel to take place alternately with the periods of
combustion by air. This intermittent working does not however offer a final solution
of the problem.
It is also known that a certain proportion of water vapour has been added to air
for combustion in gas generators, with the object of lowering the temperature of
combustion, and of regenerating a portion of the ammonia which is destroyed by

page_text: distillation at a high temperature, and also of having a certain proportion of
hydrogen in the gases, which allows of diminishing to some extent the loss of 30%
which has been inherent until now to this method of gasification of the fuel.
Now this invention relates to a method of converting all kinds of fuel into a
gaseous form by water vapour, the necessary additional heat being supplied by
superheated steam for the one part, and a small portion of air also superheated for the
other part, such superheating being preferably effected by the gas produced. By
utilizing the heat of the escaping gases for superheating the entering gases (water
vapour and a small fractional quantity of air), if the theoretical conditions of radiation
equal to nil, and of perfect regeneration of the heat of the escaping gases, could he
realized, the conversion of a solid fuel into a cold gaseous fuel having a calorific
efficiency exactly equal to that of the former could be effected. It is true a part of
the hydrogen will be substituted for an equivalent quantity of carbon, but the same
total amount of utilizable units of heat will be obtained in the gas as in the original
fuel. Moreover there will be produced gases that are comparatively rich, and are
capable of producing the highest temperatures, whilst gas generators supplied with
air alone produce gases that are considerably diluted with nitrogen.
Since the gases produced according to this invention can be made of greater
richness the higher the temperature to which the steam is superheated, and corre-
spondingly reducing the amount of air for combustion, this superheating is effected
not only by contact with the escaping gases, but by the combustion of a small
quantity of these gases with the necessary quantity of air in an apparatus of the
regenerator type, preferably indirect, in which the necessary steam and supple-
mentary air are superheatod. The steam and air may be mixed, or be introduced
separately, or a portion of each may, if desired, he first sent into the ash pit of the
apparatus, so as to become beated by cooling the ashes.
In case it should become necessary to still further raise the temperature of the
steam and supplementary air, this can be effected (1) by causing the combustion of
the heating gases to take place under pressure, and (2) by superheating the gas and
air to be burned in the recuperator.
It will be noted that the heat thus diverted, and taken from a part of the gases
already produced, is only an advance made to the principal reaction, i.e. to the
combustion by steam, and will be found intact at the exit, as the entire process may
be considered as a cycle in which no loss of heat whatever takes place.
By superheating the water vapour, another advantage which has previously been
sought for, is obtained and which renders the improved process of still further value.
It has long been known that the distillation of coal, under ordinary conditions entails
the loss in the inactive state of a considerable proportion of the contained nitrogen,
and of which only about the tenth part of the possible amount is recovered in the
form of ammonia. It has been proposed, in order to regenerate a portion of this
aminonia, to distil and burn the fuel at the lowest possible temperature, and with this
object, it has been proposed, as hereinbefore mentioned, to add water vapour to the air
intended for combustion, but, as will be understood, without superheating such water
vapour. The opposite plan has also been adopted, viz., that of using water vapour
alone, indirectly superheated, and although the apparatus employed has not been
suitable for operations on a large scale for the reasons hereinbefore mentioned, the
yield of ammonia was considerably increased.
In the present process, on the contrary, the superheating of the steam and of the
supplementary air, is effected by an exchange of temperature with the escaping gases
of combustion and by the combustion of a portion of these gases in an apparatus
specially adapted for the purpose, and of the type of regenerator employed in glass
making and in metallurgy. The superheating is thus effected without additional cost,
and the small quantity of air mixed with the steam is not sufficient to check the
favourable part played by the steam in the production of ammonia, even at high
temperatures. Thus according to this invention solid fuels can be gasified into cold
rich gaseous products without any loss whatever due to the conversion, and without
cost, theoretically, for heating, whilst producing a high yield of ammonia,

page_text: Apparatus for carrying out the process may be of various forms. The chief feature
that distinguishes such apparatus from the ordinary gas gonerators, is the absence of
grates either horizontal or inclined, which are replaced by vertical walls along which
the oxidation takes place, and combination of such apparatus with the steam and air
superheating apparatus.
A cylindrical cr prismatic furnace or cupola without a grate, may be employed,
closed at top and bottom, provision being made for charging the fuel (coke, coal,
lignite, anthracite &c.) into its top, and for allowing of the discharge of ashes at the
bottom, by means of any suitable automatic arrangement.
The steam and air necessary for the gasification are first caused to regenerate or
absorb the heat carried off by the gases of distillation and combustion, and are then
passed into what may be called the regenerator by analogy of construction with
similar apparatus used in other industrial processes but which have heretofore been
employed for a somewhat different object. This regenerator, preferably indirect, and
of the Ponsard, Lencauchy or other similar type, is arranged as near as possible to
the furnace or gas generator, it may be in the wall of the furnace itself, or even at
the centre of the gas generator, which thus becomes annular. Through one of the
conduits of the generator steam and air are caused to circulate, and through the other,
a portion of gas preferably taken from that produced in the generator, and previously
washed to remove ammonia therefrom. This gas mixed with the desired quantity of
air for burning the same (both being superheated if required) serves to effect the
superheating of the steam and air to be gasified, which pass out of the lower part of
the generator, and up through the layer of fuel, burning the latter with formation of
carbonic oxide and hydrogen.
If desired, a regenerator of the Whitwell, Cooper, Siemens, or other similar
type, might be employed. It will be seen that the walls play the part of heating
surfaces and replace grates.
If there should remain a slight excess of heat in the escaping gases, it can be
employed to generate the necessary steam.
The accompanying drawings illustrate three different arrangements of apparatus for
carrying out this invention.
Figs. 1 and 2 being vertical sections at right angles to each other and Fig. 3 a
horizontal section of one arrangement.
Figs. 4, 5 and 6 being respectively similar views to Figs. 1, 2 and 3, illustrating a
second arrangement; and
Figs. 7, 8 and 9 which are also similar views to Figs. 1,
illustrating a third arrangement.
In each of these arrangements
and 3 respectively
A is the chamber for the fuel to be gasified; this chamber may be of annular
form in cross section as in Figs. 1 to 6 inclusive, or of rectangular form as in
Figs. 7, 8 and 9.
B is the passage or passages for steam or steam and air communicating with the
lower end of the chamber A.
the heating flue wherein a portion of the gases obtained from the fuel are burnt
with air to heat the passage or passages B.
D is a pipe or collector for the gases produced. E is an apparatus, for example a
coil as shewn, wherein the steam or steam and air on their way to the passage or
passages B are superheated by the hot gases passing from the chamber A to the pipe
or collector D. O is an outlet for the discharge of ashes. T is the charging hopper
(or hoppers) for fuel to be gasified.
Another arrangement of gas generator consists of a series of rectangular furnaces,
joined together by a wall as in Appold's coke ovens, the regenerators alternating
with the furnaces proper, or they may be situated externally, but very close to the
wall.
The gases may be forced, or drawn, or impelled by steam by means of any suitable
apparatus such as a Körting apparatus.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The herein described, method or process of gasification of fuel by means of
superheated steam and air introduced into the gas furnace or generator either in a
mixed state or separately.
2. In the gasification of fuel as herein described, the use of continuous gas
generating apparatus constructed with a vertical, or nearly vertical wall or walls, that
replaces or replace the horizontal or inclined grates usually employed, and along
which the oxidation of the fuel or combustible matter is effected.
3. For conducting the process of gasification of fuel herein referred to, the nse in
conjunction with a gas generating furnace of superheating apparatus for preliminarily
raising to a high temperature, the steam, and also if requisite the air, which is or are
necessary to effect the gasification of the fuel, (the steam and air when both are
heated, being heated either separately or together) and also if necessary for heating
the air and gas the combustion of which furnishes the heat for producing the final
superheating of the steam and air.
4. The improved apparatus for the gasification of fuel, comprising a vertical gas
generator or furnace, in which solid fuel is converted into a gaseous condition,
superheating apparatus heated by a portion of the gases escaping from the gas
generator or furnace, and a combustion chamber wherein gas and air are burnt to
further superheat the steam and air before passing into the gas generator or furnace
substantially as herein before described with reference respectively to and shewn in
Figs. 1, 2 and 3; in Figs. 4, 5 and 6; and in Figs. 7, 8 and 9 of the drawings
annexed.
Dated this 24th day of Ontahor 1800
W. LLOYD WISE,
Per J. F. Brougham.