Improvements in and Apparatus for Obtaining Cyanogen, Oyanides, and other Products from Carbonaceous Matter or Substances Containing Ammonia or Nitrogen or Compounds thereof.
Year: 1893

page_text: Date of Application, 23rd Feb., 1893
Complete Specification Left, 27th Dec., 1893-Accepted, 22nd Mar., 1894
PROVISIONAL SPECIFICATION.
Improvements in and Apparatus for Obtaining Cyanogen, Oyanides,
and other Products from Carbonaceous Matter or Substances
Containing Ammonia or Nitrogen or Compounds thereof.
I, HENRY AITKEN, of Darroch, near Falkirk, in the County of Stirling, North
Britain, Coal Master, do hereby declare the nature of this invention to be as
follows:
1
When carbonaceous matters or substances containing ammonia or nitrogen or
compounds thereof are consumed or treated more particularly when this is done at
high temperatures the nitrogen is in part converted into cyanogen or compounds
thereof but this cyanogen or compounds thereof is or are decomposed if not taken
off at once from the hot carbonaceous matter.
According to my invention I provide means as hereinafter described for securing
this cyanogen or compounds thereof.
My invention may be applied to any of the usual apparatus now in use when
coal, coke, charcoal, peat, shale, or other carbonaceous or combustible substances
are used, such as in blast furnaces for smelting iron and other ores, or oil or gas
producers of the blast furnace type, or the Siemens type or any other apparatus
where the circumstances are similar to those attending the use of the said furnaces
or producers or are favourable for the purposes of my invention, the blast furnace
or gas or oil producers performing its or their other functions as hitherto, or a
special gas producer may be made and the improvements applied thereto and the
apparatus be worked solely for the purpose of making cyanogen, cyanides, and
other products according to my invention, the gas made at the same time being
utilized as desired.
In applying this improvement to a blast furnace such as those used for making
pig iron I proceed as follows:-If no hole or holes be in existence I make a hole
or holes a little above the highest level that the slag is allowed to rise to in the
furnace and in this hole or these holes I insert a pipe or pipes which may be made
of any suitable metal, clay or other material provision being made by means of a
knee with a moveable cover for keeping the pipe or pipes clear, or this pipe or
these pipes may be kept clear by means of a scraper or scrapers working through
a stuffing box the scraper being drawn back from the current of the gases. The
said pipe or pipes should be placed at an angle upwards as it enters or they enter
the furnace so as to prevent dust entering the pipe or pipes and it or they may be
protected by a water jacket or coil of pipes through which water flows as is well
known in blast furnace practice. A dust trap or catcher may be attached to the
pipe or pipes which catcher may be a simple chamber or a chamber with a division
or the chamber may have a filter or filters preferably made of asbestos. From the
chamber the gases are forced or drawn into condensers where they are cooled and
thereafter presented to any substances with which the cyanogen or cyanides will
combine or by which they will be absorbed and, if required, are then treated by
any known or suitable method and made marketable.
For instance the cyanogen or cyanides may be absorbed by soluble or insoluble
salts of iron, such as sulphate of iron, chloride of iron or oxide or carbonate or
sulphide of iron using one or more of these as is well known to chemists the same
being mixed with an alkaline salt such as a salt of potash or soda and thus ferro-
cyanide can be produced if desired.
In place of cooling the gases down they may be presented hot to such absorbers.
When the gases are cooled down the heat may be utilized for example for raising
| steam or for heating water or otherwise.

page_text: If the cyanogen be in the state of cyanides the gases may at once be passed into
water and the products be absorbed by the water, or the water and products may
be applied to the reduction of metals, either in the manufactured state or when in
the state of ores or the gas may be passed through among the metals or into the
pulverised ore containing the metals which I prefer should be damp or wet.
When it is desired to make ammonia from the cyanogen and cyanides I pass
them through lime or a mixture of lime and water or other alkali or any other
suitable process may be used for converting the cyanogen or cyanides into
ammonia. The ammonia may be converted into sulphate of ammonia by passing
it through sulphuric acid or other compounds of ammonia may be made by any
other suitable process.
As regards the point in the blast furnace from which to take away the gases
this should be placed well down in the furnace and the best results will I
believe be obtained by taking them off just above the level to which the slag
is allowed to rise but I do not restrict myself to this point as I may take
them off farther up the furnace but I believe if taken off much farther up the
gases will be found to contain less cyanogen. I prefer to take off the gases as
far away as possible from the tuyeres so that as generally is the case when no
tuyere is in the front of the furnace I place the offtake pipe or pipes above
the slag hole, or in making a new furnace the tuyeres may be placed away
from the outlet pipe. My object in so taking off the gases is to avoid as far
as possible any admixture of free oxygen with the gases taken off.
In so
working a blast furnace extra carbonaceous matter may be added with a little
extra lime to equal the quantity of gas which is taken away so that the
quality of the iron made is not affected. The gases after being freed of their
cyanogen or other products may be used for raising heat or they may be driven
back into the furnace with or without air. I prefer when so re-introducing the
gases into the blast furnace to put them in as far away as possible from the
outlet where the gases are taken off. In place of taking off the gases by a
hole or holes through the side I may take them off by means of a tube or
pipe hung or supported in the middle or side of the furnace. This tube or
pipe is continued down into the furnace as far as it is convenient and as far as
the said tube or pipe will stand the heat. This tube or pipe should be widest at
the top so as to admit of the burden passing it freely and it may be made of iron
or other metal or fire brick or other suitable material. The tube or pipe is
continued out at or near the top of the furnace.
The like arrangements are used when taking gases off from gas producers of the
blast furnace type.
In taking the gases off from gas producers of the Siemens description or the
like I take care to draw or force the gases through as much hot carbonaceous
matter as possible and directly from the hot carbonaceous matter.
In taking off the gases for this object from apparatus such as retorts or kilns
used in making oil such as apparatus used at mineral oil works for making mineral
oil from coal or shale I take off the gases from the top of the hot combustion zone
and not in the distilling zone and I do not allow them to pass through the upper
part of the kiln or retort-or I may allow a part to pass up to the top of the retort
or chamber. The gas after being freed from its cyanogen or cyanides may be
reintroduced into the bottom of the retort or chamber.
In working such apparatus the combustion is effected by air or steam or both.
In many cases the shale used contains too little fixed carbon to raise the necessary
temperature required for the purpose intended or for fluxing the earthy matter of
the shale into a flux if this be done in such cases I add coal preferably blind coal
or coke or charcoal with the shale or I add combustible gases to obtain the required
temperature.
When I desire to produce as much cyanogen as possible from carbonaceous
matter I construct an apparatus of the following description. I erect two chambers
preferably of fire brick covered outside with sheet iron. These chambers com-

page_text: municate at the upper part by means of a passage or flue and they are provided at
the bottom with inlets and valves by which air or air and steam are forced or
drawn in. I prefer to place these on the outside of the chambers. In the centre
of the chamber or bottom but preferably towards the centre I provide outlets
covered over so that the ash or coke cannot fall through them and furnished with
pipes and valves. Both chambers are filled with carbonaceous matter and fired
up till there is a considerable body of the carbonaceous matter raised to a high
heat. Air or air and steam are admitted to the bottom of No. 1 chamber and the
products of combustion and distillation are passed therefrom into No. 2 chamber
and pass down through the carbonaceous matter therein and out at the bottom and
are then treated in order to get the cyanogen or products required. When this
has been continued for some time the current is reversed and the air or air and
steam forced or drawn in at the inlet valve at the bottom of No. 2 chamber the
outlet valve then being closed and the inlet valve on No. 1 chamber closed and
the outlet valve of No. 1 opened. After this is continued for a time the current
is again reversed and so on carbonaceous matter being added from time to time to
both chambers. The gases after being freed of their cyanogen, cyanides and other
products may be used for any purpose desired. When working this type of gas
producer and when the ash of the carbonaceous matter is made into slag preferably
by the admixture of lime or other alkali such as soda or potash or other flux, I
place the gas outlets above the bottom and above the level to which the slag rises.
These outlets rise from the inside of the producer at an angle upward so as to
prevent anything closing them and a ledge may be placed over these outlets with
the like object.
In place of using two chambers I may only use one chamber which is worked in
the following manner-I force or draw air into the bottom of the chamber and so
consume a portion of the carbonaceous matter heating up the remainder and taking
off the gas at the top I then force in air at the top with or without steam and draw
off the products at or near the bottom.
In working this improvement the oxygen of the air should be thoroughly or as
thoroughly as possible converted into carbonic acid and carbonic oxide and no free
oxygen should be present and the gases should be at once taken off from the hot
carbonaceous matter and it is desirable in order to obtain good results to have an
alkali such as potash, soda or lime present in the carbonaceous matter.
These gases particularly when raw coal (excepting blind coal) or shale or wood
are consumed will usually contain acetylene this I secure by cooling the gases down
and filtering or passing the gases through water or preferably through oil or tar or
other absorber.
The said gases will often contain bisulphide of carbon this will be secured in like
manner.
In order to convert ammonia or any convertible nitrogen or compounds thereof
which may be in other gases into cyanogen or compounds thereof I force or draw
so much of these gases with the air or steam into either of the apparatus last
described or into any blast furnace gas or oil producer and so convert the ammonia
or compounds thereof into cyanogen or compounds thereof or these gases may be
forced or drawn in slightly above where the air or steam enters.
When such gases
are forced into a blast furnace I prefer that they should be thoroughly dried and
freed from all watery vapour or such gases may be treated for the like object by
passing them up through hot carbonaceous matter in a retort placed by preference
vertically.
The carbonaceous matter to be placed in such retorts I prefer should be of an
easily decomposible character such as wood-charcoal or wood. If wood be used
the gases should pass downwards. In all cases I prefer to have an alkaline
substance present in the carbonaceous matter.
Dated this 23rd day of February 1802
J. H. JOHNSON & Co.,
Agents.
.

page_text: Improvements in and Apparatus for Obtaining Cyanogen, Cyanides,
and other Products from Carbonaceous Matter or Substances
Containing Ammonia or Nitrogen or Compounds thereof.
I, HENRY AITKEN, of Darroch, near Falkirk, in the County of Stirling, North
Britain, Coal Master, 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 :-
When carbonaceous matters, or substances containing ammonia, or nitrogen, or
compounds thereof, are consumed, or treated, and more particularly when this is
done by the application of high temperatures, the nitrogen is in part converted into
cyanogen, or compounds thereof, but the said cyanogen, or compounds thereof, is,
or are, decomposed if not taken off at once from the hot carbonaceous matter.
According to my invention I provide means, as hereafter described, for securing
the said cyanogen, or compounds thereof.
My invention may be applied to any of the usual apparatus now in use when coal,
coke, charcoal, peat, shale, or other carbonaceous, or combustible, substances, are
employed as for instance in blast furnaces for smelting iron and other ores, or oil, or
gas producers, of the blast furnace type, or of the Siemens type, or ordinary shale
oil retorts, or any other apparatus where the circumstances are similar to those
attending the use of the said apparatus, or are favorable to the purposes of my
invention, the apparatus performing its, or their, other functions, as hitherto, or
special gas producers may be made and the improvements applied thereto and the
apparatus be worked solely for the purpose of making cyanogen, cyanides, and other
products, according to my invention the gas, made at the same time, being utilized
as desired.
In carrying out my invention as applied to an apparatus such as a blast furnace
for making iron I proceed as follows and I add to the blast furnace the plant shewn
in the section of a furnace Figure 1. A is the bottom portion of the furnace, B is
the slag outlet, k the tapping hole; O the gas outlet at the top and P the charging
bell, C are the tuyeres on one side of the furnace; D is the recess, or space, into
which the pipe E is put for taking off the gases which pipe is furnished with a valve
at M. The pipes E and F should be lined inside with fire brick. N is a closable
opening which may be used to clear out the recess D, and F is a pipe connecting
the pipe E to the chamber G constituting a dust catcher. This chamber G may be
of any convenient shape for catching dust and may be furnished with screens which
may be made, for instance, of wire cloth, or asbestos cloth, and be provided with
rotating, or other, brushes, capable of being moved in contact with the said screens,
for the removal of the dust therefrom. HH are manholes for withdrawing the
dust. The dust catcher may, for example, be made in the same way as the dust,
or fume, catchers used in lead reducing works, and may be furnished with scrapers,
and arrangements of double valves, or doors, whereby the dust may be taken out
while gas is passing through the chamber, or in place of, or in addition to, such an
arrangement pipes containing water may be placed in the chamber with scrapers
like "Green's" or "Turbell's "
water heater and the heat utilized, or a steam or
water jet may at once be used to deprive the gases of their heat preferably using
the water over and over again. After the gases have deposited as much as possible
of their dust they may pass by the pipe I to the scrubber J, containing at bottom
the solution hereinafter referred to." In this scrubber is placed a shaft R and on
this shaft are placed perforated plates jand the spaces between these plates are filled
with twigs, or brushwood, or the like. The shaft, plates, and brushwood, or the
like, are caused to revolve by any suitable means, such as power applied to the
wheel S. The gases are forced, or drawn, over the absorbing material, contained
a

page_text: out.
in the bottom of the scrubber, and through the brushwood, or the like, which is
covered with the absorbing material from the bottom of the scrubber J. Preference
is given to those types of washers that cause the gas to flow to the bottom of the
compartments in the washer, or those where the liquor falls through the gases, or
those where the plates, brushes, wire-gauze, or cloth, revolve, and at the lower
portion of their revolution take up the iron salts, or other matters, from the bottom
of the washer, or scrubber, to present then at the upper part of their revolution to
the gases. The absorbing material is run in by a U pipe inserted at Z near the gas
outlet pipe and passes out at the U pipe K, and the gases pass out at W. These
washers, or scrubbers, may be of any other suitable, or desired, form, such as those
used at gas works, and iron works, for cooling and washing gases. Before passing
through the scrubber J the gases may be passed through a washer, or scrubber,
containing water, to take out any cyanide of potassium, that may remain in them
from which water it is afterwards extracted. The gases are thereafter used for any
purpose for which they may be useful, or they may be forced, or drawn, again into
the blast furnace with, or without, air. Where this is done I prefer to force them
in hot and dry and as far away as possible from the point at which they were taken
The dust collected as aforesaid may be treated with water so as to extract
the cyanide, and the liquid is then treated by any known, or suitable, means to
obtain, or convert, the cyanide into the marketable form desired, or the process
hereinafter described may be used and cyanide be obtained. So far as I have yet
ascertained the dusts contain cyanogen only in the form of cyanide of potassium,
but further investigation may prove that it is there in some other form so it may be
necessary to treat the said dusts by the mixture of iron and alkaline salts as herein-
after described to obtain all the cyanogen. Or the dust, if rich enough in cyanide,
may be used for any purpose for which it is desired. The absorbing material to be
used in the washer, or scrubber, may be soluble, or insoluble, salts of iron, such as
sulphate of iron, chloride of iron, or oxide, or carbonate, or sulphide, of iron, using
one, or more, of them, it, or they, being mixed with an alkaline salt, such as a salt
of potassium, or of sodium, and thus ferro-cyanide is obtained which can be treated
by any known, or suitable, process to bring the cyanogen into the marketable
condition desired. The amount of soluble, or insoluble, salts of iron to be used will
depend, of course, on the amount of cyanogen in the gases, and the alkali, soda or
potash, should be in chemical equivalent to the amount of iron in the iron salt
employed thus forming an alkaline solution in which the iron salt is suspended, or
dissolved. For example if ferro-cyanide of potassium be the product desired there
would be used 276.4 parts (by weight) of carbonate of potash and 56 parts of
metallic iron in the form of an insoluble salt and if ferro-cyanide of sodium he
required there would be used 212 parts of carbonate of soda to 56 parts metallic
iron in the form last mentioned adding water as required. In making the 56 parts
of iron into an insoluble salt of iron I may proceed as follows:-I take waste liquor
from the galvanizing works and add 106 parts of the best commercial carbonate of
soda for every 56 parts of iron dissolved in the waste liquor. This throws down
carbonate of iron. The clear liquor (which is of no value) is run off and the
precipitated iron is used. It is of importance that all scrubbers used should be of
such a construction that the suspended iron as well as the solution will be presented
to the gas.
I
In place of utilizing the cyanogen, or compounds thereof, in the aforesaid manner,
may at once direct the gases into tanks or receptacles containing metals, or ores
containing metals (to which by preference water is added) in order to dissolve the
metals, or extract the metals from the ores, sufficient cyanogen, or compounds thereof.
being used to take up the metals desired and any excess of cyanogen can be utilized
in treating other metals, or ores. The dissolved metals can be utilized, or obtained,
by any of the means now known. In place of treating the gases for the deposit of
the dust as described, the gases may be filtered through sand, or gravel, or stones,
or like material, and thereafter be washed out, or by passing them through wire
gauze, or asbestos cloth, which may be placed on a revolving drum, brushes being

page_text: used to remove the dust therefrom; or the wire, or cloth, may be mounted on
frames or drums, provided with brushes, rotating, or moving, in contact therewith
to remove the dust; or 1 may use electricity to deposit the dust; or I may pass
the gases through oil, or tar, or I may use steam, or water, or oil jets, preferably
impinging the gases onto wire-work such as fine sieves, or porous asbestos cloth.
.
When blast furnaces are "slagged," or cast; a great amount of gas passes away
and is lost, this I collect by means of a pipe put over, or into the aperture, or
holing, by which the slag comes out and I treat the same as hereinbefore described.
This pipe may be made in an inverted T shape, the slag flowing straight through,
and the gas being taken off at the top end of the T, or the inverted T shaped pipe
has added to it a U shaped portion the gas passing through the top end of the T-
whilst the slag passes through the other end and also through the U shaped portion.
Figures 2 and 3 illustrate these pipes. a is the end put into the slag hole of the
furnace; is the pipe to which a pipe is attached to take off the gases and c is the
slag outlet. In Figure 3 the same parts are similarly lettered but the slag pipe
has a U shaped portion through which the slag flows. The ends of pipes at a in
place of being made conical as shown may have flanges and clay be used to make
the joint good. In place of the pipes for taking off the gases I may place a
chamber with a moveable lid and connect the gas pipe at the top. This chamber is,
or may be, required to hold the dust and slag that is blown forward. I may use au
air pump, or ejector, or injector, and draw the gases from the top of the slag. I may
treat the gases as herein described, or I may run the slag by a pipe, or passage,
into a chamber and take the gases off from the chamber. When so taking off the
gases and slag prickers working through stuffing boxes should be provided for
keeping the slag hole clear.
In place of taking off the slag and gases as herein before described, I may do so
by means of an iron, or brickwork, chamber, built on, or pushed on, at the slagging
hole, which chamber has a division across the direction the slag flows and a hole in
the bottom of the division through which the slag flows and by putting a lid, or
cover, over the arrangement the gas is taken off by means of a pipe, or pipes. The
bottom of the chamber should be lower where the division is so that the slag will
flow down and then up, and so seal the gas in the chamber and force it to go where
it is wanted.
Should it be desired to convert the cyanogen and cyanides into ammonia I pass
them through lime, or mix them with lime and water, or other alkali, or any other
suitable process may be used for this purpose. The ammonia so obtained may
thereafter be treated as desired and be converted into any marketable form by any
know or suitable processes.
In order to ensure a large yield of cyanides I may add potash, or other alkali, to
the "burden," or to the blast, or force it in near the hearth, or I may add to the
blast furnace, a chamber containing potash, or other alkali, as hereinafter described.
In place of adding the potash, or other alkali, by placing it in a chamber, I may
place the alkali in a retort (which I prefer should be of iron lined with carbon) and
pass the gas over the hot alkali in the retort as in the case of the chamber. This
retort with its fire grate may be placed on wheels so that it can be run in, and out,
for repairs as desired. The alkali being added from time to time, or continuously
as desired, into the retort, or chamber. The chamber, or retort, herein referred to
containing an alkali may be dispensed with both in the blast furnace, and the other
arrangements hereinafter referred to.
In place of passing the gas over the potash or other alkali, it may be forced
through them in the chamber, or retort, or the alkali, may be fed in regularly over,
under, or alongside of the gas aperture, where the gas comes from the furnace, I by
preference introducing the alkali, into the furnace near the aperture. In place of
making the chamber horizontal, it may be placed vertically, or inclined, and the
alkali be dropped into it.
The point in the blast furnace from which the gases are taken away should be
well down in the furnace and the best results will I believe be obtained by taking.

page_text: them off just above the level to which the slag is allowed to rise, but I do not
restrict myself to this point as I may take them off further up the furnace, but I
believe if taken off much further up, the gases will be found to contain less
cyanogen. I prefer to take off the gases as far away as possible from the tuyeres so
that, as generally is the case, when no tuyere is in the front of the furnace, I place
the offtake pipe, or pipes, above the slag hole, or in making a new furnace, the
tuyeres may be placed away from the outlet pipe, which may be placed at the back
of the furnace. My object in so taking off the gases is to avoid as far as possible
any admixture of free oxygen with the gases taken off. In so working a blast
furnace extra carbonaceous matter may be added with a little extra lime for fluxing
the ash of the extra carbonaceous matter to equal the quantity of gas which is
taken away so that the quality of the iron made is not affected. The gases after
being freed of their cyanogen, or other products, may be used for raising heat, or
they may be driven back into the furnace with, or without, air. I prefer when so
re-introducing the gases into the blast furnace to put them in as far away as possible
from the outlet where the gases are taken off, and also heated. In place of taking
off the gases by a hole, or holes, through the side I may take them off by means of
a tube, or pipe, hung, or supported, in the middle, or side, of the furnace. This
tube, or pipe, is continued down into the furnace as far as it is convenient and as
far as the said tube, or pipe, will stand the heat. This tube, or pipe, may be
widest at the top so as to admit of the burden passing it freely, and it may be made
of iron, or other metal, and be lined with fire-brick, or other suitable material.
The tube, or pipe, is continued out at, or near, the top of the furnace. Should it
be found that the cyanogen is in greatest part contained in the dust and that it is
not worth while treating the gases farther, then they are simply passed through
chambers, or filters, and the dust extracted and the gases put back into the furnace,.
their passage being assisted by pumps, or fans, or other means.
The like arrangements are used when taking off gases from gas producers of the
blast furnace type.
In taking the gases off from gas producers of the Siemens description, or the like,
I take care to draw, or force, the gases through as much hot carbonaceous matter
as possible and directly from the hot carbonaceous matter.
Potash, or soda, or other alkali, may be added to the material, or in a chamber
placed to the side of the producer as herein described.
In taking off the gases for this object from apparatus such as retorts, or kilns,.
used in making oil, such as apparatus used at mineral oil works for making.
mineral oil from coal or shale, I take off the gases from near the top of the hot
combustion zone, and I do not allow them to pass through the upper part of the
kiln or retort; or I may allow a part to pass up to the top of the kiln, or retort..
The gas after being freed from its cyanogen, or cyanides, may be re-introduced
into the bottom of the retort, or chamber, with, or without, air, or steam, or I may
work retorts, such as vertical retorts, by taking off all the products at, or near, the
bottom, thus causing all the gases to pass through the hot zone.
In working such apparatuses the combustion is effected by air, or steam, or both,
or where retorts are used these may be worked without the addition of either air
or steam. In many cases the shale used contains too little fixed carbon to enable
the temperature required for the purpose intended, or for fluxing the earthy matter
of the shale into a flux, (when a flux is made) to be attained and then I add coal,
preferably blind coal or coke, or charcoal, with the shale, or I add combustible gases
to obtain the required temperature.
When it is desired to produce as much cyanogen, or cyanides, as possible from
carbonaceous matter, or carbonaceous matter containing nitrogen or compounds
thereof which may be of any description (organic or inorganic) such an apparatus
as is shewn in section in Figure 4 may be employed.
A A are the barrels or chambers of the producers which may be made of any
convenient length. P are the charging hells, by which the material is introduced
to the producers. p are valves so that the charging bells P may be closed when the
carbonaceous matter is dropped into the producers. B are the slag holes. k, k, the

page_text: holes at which any molten metal which may be produced is run out. This apparatus.
may be furnished with arrangements for collecting the cyanide and cyanogen the
same as, or like those hereinbefore described and illustrated in Figure 1. In
working this apparatus both chambers are filled with carbonaceous matter with
the required amount of lime, or other flux, to flux the ash, when the ash is fluxed
and not taken out as ashes at doors provided at the bottom of the producers for
the removal of the ashes. Fire being applied at once and the carbonaceous
material added, as the heat comes through, in order to ensure that the whole
body of material is heated, the blast, preferably hot, is then supplied to the
tuyeres shewn on one side of the producer at C the outlet at the bottom being
closed by dampers i and the resulting gases are forced up through producer No. 1,
through the flue Y and down through the material in the producer No. where
they pass out at E, and are then treated as hereinbefore described. This is
continued for a time depending on the nature of the material, but so soon as the
carbonaceous material in the bottom of chamber No. 2 is not at a high heat, the
current must be changed and the valves in chamber No. 2 be closed and the
valves in chamber No. 1 be opened and the blast valve, on chamber No. 1 closed,
and the blast valve on chamber No. 2 opened and so the current is reversed, and
thus the process goes on, carbonaceous matter being added from time to time as
required. To the carbonaceous matter may be added potash, or other alkali; or
I may add it with the blast; or I may pass the gases through the chambers e
(Figure 4) in which potash, or other alkali, is placed from time to time; or the
alkali may be fed regularly into the chambers e as the current of gas passes through
it; or the alkali may be added by the other means hereinbefore described; or I
may use a retort containing alkali; or I may also add with the blast materials
rich in nitrogen, or its compounds; or I may place such materials in, or run them
into the chambers e with the alkali. The said chambers e may be constructed
separately and be mounted on wheels and bolted in position as this will give
convenience in removing and clearing out. It is important when the air blast is
shut off that no air be allowed to pass into the bottom of either producer when not
required. I therefore place three valves in the air supply pipe, one valve opening
to the outside air, so that, when the two valves on the supply pipe are closed, the
valve opening to the outside is opened thus ensuring that no air can possibly get
into the bottom of the producer when not required. The like arrangements of
valves or dampers may also be placed at ii. By lengthening the passages E
double dampers or valves can be put there. Such an arrangement as this may be
used for smelting iron, or other metal, and the metal be tapped out by the tapping
holes k. By this arrangement carbonates of iron (more particularly carbonates of
iron containing volatile hydrocarbons and fixed carbon) are reducible and the
volatile carbons, nitrogen, and fixed carbon, can be utilized, and the metal be
obtained from the ore provided that the sulphur is not in excess. The gases after
having been freed of their cyanogen may be forced, or drawn, back into the furnace
or they may be utilized for other purposes. In place of working with two chambers
I may work with a single chamber by allowing the gases to pass off at the top for a
time and then forcing in air, or steam and air, at the top, or in place of air, or
steam I may force or draw in air at the top taking off all the gas at or near the
bottom or in place of air I may force or draw in at the top gas, such as producer,
or blast furnace, gas or other gases, containing nitrogen, or compounds thereof,
which I prefer to be heated, the gas being drawn off at the bottom and treated as
herein before described. The introduction of air or gas at the top is then stopped
and the air is forced or drawn in at the bottom and so the process is carried on.
In working both the blast furnaces and producers it may be found that there is
too much pressure caused by the great quantity of material the gases have to pass
through. This I overcome by putting in one, or more, extra boshens," or I
may use any of the means described for an analogous purpose in the Specification
of Letters Patent granted to me No. 576 dated the 16th February A.D. 1874
and No. 2682 dated the 8th June A.D. 1882. I should here remark that in
66

page_text: "
taking off gases from blast furnaces, and the other apparatus herein mentioned, it
is of importance to note carefully the composition of the nature of the "burden
used in the blast furnace, or the material used in the other apparatus, as many
coals contain more potash, nitrogen, or compounds thereof, than do others and many
ironstones contain more potash, and some more soda than do others. For instance,
as a rule, all the blackbands and clay bands, contain potash, so that furnaces using
these ores are the most suitable for taking off the gases, as then cyanide of
potassium is got, and, in these cases, I have found that the cyanide of potassium
is obtained in great part in the dusts.
When it is desired to make an ordinary producer gas and also a hard gas and
cyanogen, or compounds thereof, I construct an apparatus as shewn in vertical
section in Figure 5 and in horizontal section in Figure 6 and carry on, at the same
time, the making of ordinary producer gas and hard gas, with the obtainment of
cyanogen, or compounds thereof. In this case I prefer to place the tuyeres C C C
on one end of the furnace and to allow a certain quantity of the gases to pass off at
the top in the usual manner. The remainder I pass out at the bottom by the
aperture E. In these figures A is the barrel of the producer, B the slagging hole.
k is the tapping hole, and e is a compartment built in, or connected to, the producer.
X X2 indicate holes by which potash, or other alkali, or substances containing
nitrogen, or compounds thereof, such as horns, or hoofs, or the like, may be
introduced. When gases rich in nitrogen, or compounds thereof, are added, it is
preferred to add them at X in regulated quantity to the quantity of gas passing off
at the bottom. The gases taken off at the bottom are treated as hereinbefore
described, and the gases taken off at the top may be utilized as they leave, or before
being so utilized they may be deprived of their hydrocarbons, water and ammonia.
I may also work the apparatus in the following manner.
After the apparatus
has been at work for a time I close the outlet to the top, shut off the blast and
force producer or blast furnace gas, or other gases containing nitrogen,, or
compounds thereof, in at the bottom by the tuyeres CCC and pass them through the
hot carbonaceous matter for a time, or I may force such gases in at the top and down
through the material and out at the bottom. Such gases should contain nitrogen,
or compounds thereof, so that they may be decomposed into cyanogen. I prefer
to heat such gases before they enter the chamber, these gases may be heated in
pipes or by means of heaters such as those known as Cowper's stoves or Siemens
regenerators. After the gases have so passed through for a time the gases are
cut off, and air is added at the bottom, and the top exit is partly opened and the
process is carried on as before. Or such an apparatus as this may have a set of
tuyeres placed above those shewn in the plan so as to prepare the fuel coming
down. In this case it is well to broaden the producer that is to make the
distance from the tuyeres to the chamber e greater. Where it is desired to make
large quantities of cyanide I construct an ordinary producer taking off the
products at the top. Into this producer there is charged wood, charcoal, or coke,
and alkali, all being not only dry but hot, and air is forced in (preferably hot
air) at the bottom. In this case also I may add organic or inorganic substances
rich in nitrogen or compounds thereof alternately gas containing nitrogen or
compounds thereof and no air or I may add these gases above the air entrance
and work in this way continuously.
From what I have described it will be clear to anyone with ordinary knowledge
of apparatus to which my invention relates that such an arrangement as this can
be easily applied to gas producers of the ordinary type where the air is forced, or
drawn in.
In the foregoing arrangements 1 have shewn the air as being forced in but the
air may be drawn in, with, or without, steam.
In place of cooling down the gases from near the bottom of the blast furnace
or producer I may (in order to avoid all risk of explosion), shortly after they
leave the furnace, or producer, force, or draw them off with steam or water or
through water and treat them thereafter as herein described.
R

page_text: In heating up the carbonaceous matter, before starting to work, with any of
these arrangements I prefer to heat the whole body of material slowly charging
raw material as the heat breaks through.
All these arrangements where the ash is fluxed may not only be used for
producing gas but metals may be reduced in them at the same time and be tapped
off as required.
When employing in these arrangements material which cakes, or softens, I may
use stirrers such as those described in the Specification of Letters Patent granted
to me No. 2682 dated the 8th June A.D. 1882. In all these arrangements I may
supply with the air, steam, or blast furnace, or producer gases or other hydrocarbon,
in a liquid, solid, or gaseous state.
When the ash is not fluxed, as is intended with the apparatus hereinbefore
described, doors are placed on the bottom of the apparatus by which the ash can
be removed.
It is of much importance that all the air supplied for the combustion of the
carbonaceous matter should be as perfectly as possible decomposed into carbonic
oxide so that no free oxygen be present to affect the cyanogen the gases being
taken off from the hot carbonaceous matter, and I prefer that the air used be
heated.
These gases, particularly when raw coal (excepting blind coal) or shale, or wood,
is consumed, will usually contain acetylene and this I secure by cooling the gases
down, filtering, or passing, the gases through water, or preferably through oil, or
tar, or other absorber.
The said gases will often contain bisulphide of carbon; this can be secured in
like manner.
In order to convert ammonia, or any convertible nitrogen, or compounds thereof,
which may be in other gases, into cyanogen, or compounds thereof, 1 force,
or draw, these gases (with or without air, or steam, or both) into either of the
apparatus last described, or into any blast furnace, or gas or oil producer, or
the like and so convert the nitrogen, or compounds thereof, into cyanogen, or
compounds thereof, but I much prefer to add such gases separately and away from
the air entrances, passing them through the hot coke as before described; or such
gases may be added when no air is going in by alternating the current of air and
such gases.
When such gases are forced into a blast furnace I prefer that they should be
thoroughly dried and freed from all watery vapour.
In using the term nitrogen, or compounds thereof, I desire to have it understood
that in this is included the nitrogen of the air. From the amount of cyanogen I
have obtained from gases taken off from near the bottom of the blast furnace it
appears that some of the nitrogen of the air is in part converted into cyanogen.
The gases made by these arrangements taken off at or near the bottom may be
at once taken and passed through metals, or ores of metals, preferably mixed with
water, and the metals be dissolved and thereafter utilized as is well known; or the
metals may be recovered from the liquid by any of the processes now known.
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. In the treatment by heat of carbonaceous matter, or substances containing
ammonia, or nitrogen, or compounds thereof; the withdrawal of gases from the
furnace, or the like, before they are decomposed by passing through the charge of
the said carbonaceous matter or substances substantially as herein before described,
and for the purpose of obtaining the products mentioned.
2. In blast or other furnaces, gas producers, kilus, retorts, or the like, in which
carbonaceous matter, or substances containing ammonia, or nitrogen, or compounds
thereof, is or are subjected to heat the employment of a pipe, or passage, or pipes,
or passages, for the escape of gases at such a point or points that cyanogen, or

page_text: cyanides, or other products, is, or are, obtained for utilization, substantially
as hereinbefore described.
3. In blast, or other furnaces, gas producers, kilns, retorts, or the like, in which
carbonaceous matter, or substances containing ammonia, or nitrogen, or compounds
thereof, is or are subjected to heat the employment of a pipe, or passage, or pipes,
or passages, for the escape of gases at such a point or points that cyanogen, or
cyanides, or other products, is, or are, obtained in the gases, in combination with
an absorber of the cyanogen, or cyanides, or other product, or products, required;
and a passage therefrom back to the furnace, or the like, or to other place where
the gases from which the cyanogen, or cyanides, or other products, has, or have,
been removed, are utilized; all substantially as hereinbefore described.
4. The arrangement of two chambers and their adjuncts and communications for
enabling them to be worked alternately in reverse directions for the production
of cyanogen from carbonaceous matter or substances containing nitrogen, or
compounds thereof; substantially as hereinbefore described and illustrated in
Figure 4 of the accompanying drawings also the modifications described wherein
but one chamber is employed as hereinbefore set forth.
5. The use in the manner, and for the purposes herein set forth, of alkali such as
potash, or soda, in the blast furnace, or other apparatus, when arranged as, and
for the purposes, herein before described and claimed.
Dated this 27th day of December 1893.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.