A METHOD OF SIMULTANEOUSLY MANUFACTURING STEEL AND LIGHTING- GAS
Year: 1881

page_text: LETTERS PATENT to Paul Aube, Managing Director of Aube's Steel and
Gas Company, of Paris, in the Republic of France, for an Invention of
"A METHOD OF SIMULTANEOUSLY MANUFACTURING STEEL AND LIGHTING-
GAS"
PROVISIONAL SPECIFICATION left by the said Paul Aube at the Office of
the Commissioners of Patents on the 21st February 1881.
PAUL AUBE, Managing Director of Aube's Steel and Gas Company, of Paris,
in the Republic of France. " A METHOD OF SIMULTANEOUSLY MANUFACTURING
STEEL AND LIGHTING GAS."
My Invention has for its object to make steel, convert iron into steel, or inferior
sorts of steel into fine steel, and to manufacture at the same time combustible gas
applicable for lighting or heating purposes. The operation can be carried out in
various ways, as follows:-
1. Iron (by this term I wish to comprise hereafter articles made of iron, and
inferior sorts of steel) is placed in a retort, the latter closed and heated to red heat.
When the retort as well as its contents has attained cherry heat, some fatty matter
is introduced into the retort, which substance is decomposed in a recess or cavity
provided at the bottom of the retort.
Hydrocarbon gases are thereby produced, while the red hot iron absorbs some
carbon and nitrogen and is thereby cemented.
If the iron is not pure, some lime or baric carbonate is added to the contents of
the retort in order to fix the sulphur or other detrimental substance that may be
contained in the iron, and if the fatty matter contains little nitrogen, a small
quantity of ammonia is added. A little water may also be added to the fatty
substance.
2. The second variation consists in placing in the retort iron, some lime or
baric carbonate, or any equivalent (purifying) material, also coke or charcoal,
or both. Simultaneously with the fatty matter a current of dry steam is introduced
into the retort.
3. The third variation consists in placing in a retort coal and lime or baric
carbonate when required, which mixture when heated develops bydrogen and

page_text: ammonia, thus promoting the rapid cementation of the iron which is subsequently
introduced into the retort.
4. The fourth variation consists in placing in a gas retort ordinary dried peat
mixed with any quantity of coal, either in pieces or in the shape of powder.
Instead of this mixture I take sometimes peat impregnated with any fatty matter,
or wood or cork impregnated with fatty matter, or a mixture of these substances,
the lighting power of the gas increasing with the quantity of absorbed fatty matter.
In this case some ammonia must be added to increase the quantity of nitrogen, and
while the heating of the retort causes a continuous production of lighting gas, the
articles placed in the retort are cemented.
Some coal or wood tar may also be introduced into the retort without prejudice
to the cementation for obtaining a superior quality of coke. Bricks or cakes made
from dried peat impregnated with fatty matter, coal dust, and tar, have given
excellent results. In these cakes the peat may be replaced by waste cork unfit for
other purposes, and steeped in some fatty matter.
All these processes described have the effect of adding carbon to insufficiently
carburetted iron or steel.
According to the length of time during which the metal is subjected to
cementation, the whole thickness, one half, or any desired part of the article may
be cemented.
In order to make the cementation of the metal homogeneous throughout its
thickness I expose the cemented articles to a current of dry hydrogen in the
following manner :-
Ordinary iron is placed in a retort and rapidly cemented by one of the processes
described, without taking any care for the even distribution of the carbon. After
the metal has cooled down I dip it into an acid bath, and place it in a varnished
retort, which is then heated to a temperature of 600 to 700 degrees.
At this temperature I introduce into the retort a current of dry hydrogen gas.
After a few hours the steel is taken out, and the carbon is found to be uniformly
distributed over the whole mass.
Bessemer steel may be treated in the same manner, dipped in acid, and exposed
to a current of hydrogen for uniformly distributing the carbon, which is often very
unequally distributed in it.
Ordinary or malleable cast iron, after having been decarburetted in the usual
way by oxides of iron, may also be made more uniform by pickling and subjecting
it to a current of dry hydrogen.
This process is applicable to armour plates, gun barrels, &c., or to any carburetted
metal for the more uniform distribution of carbon. The hydrogen serves also
for removing a large quantity of metalloids, such as sulphur, arsenic, and
phosphor.
By the term fatty matter I wish to include mineral and vegetable oils, oileaginous
grains, tar, residues of fatty substances, grease, human excrements, water containing
grease or soap, &c.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Paul Aube in the Great Seal Patent Office on the 18th August
1881.
PAUL AUBE, Managing Director of Aube's Steel and Gas-Company, of Paris,
in the Republic of France. "A METHOD OF SIMULTANEOUSLY MANUFACTURING
STEEL AND LIGHTING GAS."
My Invention has for its object to convert iron into steel, or inferior sorts of
steel into fine steel, and to manufacture at the same time combustible gas applicable
for lighting or heating purposes. This process can be carried out in various ways,
which I am now going to describe in detail. First method. Iron (by this term I
wish to comprise hereafter articles made of iron and inferior sorts of steel) is placed
in a retort, the latter closed, and heated to a red heat. When the retort, as well
as its contents, has attained cherry heat, some fatty matter is introduced into a
recess or cavity provided at the bottom of the retort, and there decomposed by the
heat of the retort. Hydrocarbon gases are thereby formed, and the red hot iron
absorbs in its open pores some carbon and nitrogen; thus, while the continued
decomposition of fatty matter produces an abundance of gas, the iron is subjected
to cementation. If the iron is pure, which occurs but rarely, nothing else need be
placed in the retort, but if the iron is not pure a small quantity of lime or baric
carbonate is added to the contents of the retort, in order to fix the sulphur that
the iron may contain, or any other substance may be added which produces the
same effects as lime or baric carbonate. In case the fatty matter used contains but
little nitrogen, some impure ammonia, such as can be obtained in the market at a
low price, may be added to it in order to obtain the quantity of nitrogen necessary
for producing a good steel. The addition of ammonia has no detrimental effect on
the quality of the gas produced in the retort. Some water may also be added
to the fatty substance, the oxygen set free by its decomposition serving to burn a
part of the carbon contained in the iron, while the hydrogen unites also with
carbon, and forms hydrocarbon-gas. Second method. It consists, like the first, in
introducing iron into the retort, and adding when required some lime or baric
carbonate, or any other substance which is known to have the effect above
described, but coke or charcoal or both is also added, and subsequently when the
fatty matter is introduced, and simultaneously with the same, a current of dry
steam is admitted into the retort. This method has for its object to increase the
quantity of gas which is produced during the cementation of the iron. Because
the decomposition of steam is more rapid than that of water, the production of
combustible gas will evidently go on with greater speed. Third method. It
consists in placing in a retort coal, with or without lime or baric carbonate. Coal
contains hydrogen and ammonia, which constituents are favourable for a rapid
cementation; consequently the cementation of the iron is obtained while manu-
facturing coal-gas, and without further cost than placing the iron in the retort.
Fourth method. It consists in placing in a gas retort either dried peat mixed with
more or less coal, in pieces or in the shape of powder, or dried peat imbibed with
any fatty substance, or wood or cork imbibed in the same manner, or coal and peat
(or cork) imbibed with fatty matter, or a mixture of two or three of the raw.
materials named. The gas produced by the dry distillation or decomposition of
these materials has a lighting power in proportion with the quantity of fatty
matter absorbed. In this case it is necessary to add some ammonia, in order to.
increase the quantity of nitrogen, according to the nature of the fatty matter

page_text: employed, and while the production of lighting gas is going on the article placed in
the retort is subjected to cementation. Wood or coal-tar may also be placed in the
retort without any prejudice to the cementation, and a superior quality of coke is
thus obtained after the decomposition of the peat, bark, and coal placed in the
retort. I have found by experience that bricks or cakes made from dried peat
imbibed with fatty matter, coal dust, and tar produce an excellent gas, and a
complete cementation of the iron. The same results are obtained by replacing the peat
by coal-waste steeped in some fatty matter, and unfit for other purposes. Articles
of iron or steel, which have not the quantity of carbon required for use, can be
cemented by one of the described methods, more or less, according to the time
during which the article is left in the retort, and which may be chosen so as to
cement the article to one quarter, one half, or any portion of its thickness that may
be desired. Supposing however the cementation to extend to the whole thickness
of the article, it is never uniform throughout the whole mass, although the
difference of homogeneity may be but slight. I have found by experience that any
article previously cemented to one third, one half, or any other portion of its mass,
can be made completely homogeneous by subjecting it to a current of dry hydrogen,
which causes the cementation to spread uniformly over the whole mass of the
article. It is therefore possible to give to the article the exact quantity of carbon
necessary for the quality of steel to be produced. My process of manufacturing
steel from ordinary wrought iron based on this principle is as follows:-I take
ordinary wrought iron, place it in a retort, and subject it to cementation for several
hours by one of the processes described at the beginning of this Specification (so as
to manufacture at the same time gas), the cementation being carried on rapidly,
but not to the whole depth of the article, and without taking care for the uniform
distribution of carbon. After the steel, obtained by incomplete cementation,
has cooled down I dip it into an acid bath, and place it in a varnished retort,
which is then heated to a temperature of 6 to 700 degrees (centigrade). At this
temperature I introduce into the interior of the retort a current of dry hydrogen.
After some hours I take out the steel, in which the carbon is found to be uniformly
distributed over the whole mass. Steel thus obtained and subsequently hammered
is preferable to cast steel. The same process is applicable to ingots of Bessemer
steel, in which the carbon is generally badly distributed; for instance, if mild
Bessemer steel, having too little carbon, is to be converted into fine steel, I place it
in a retort and produce gas by one of the processes described (or I may cement it
by means of charcoal), thereby fixing on the ingot a certain quantity of carbon.
After pickling I place it in a varnished retort, and operate as above described.
The distributing process is further applicable to malleable or ordinary cast iron, in
which, after the incomplete decarburation by oxide of iron, there is an excess of
carbon in the centre instead of at the surface. I place these pieces after the
pickling process in a retort, and subject them to a current of dry hydrogen at the
temperature above stated, whereby the carbon is uniformly distributed over
the whole mass. The distributing process is applicable to armour plates, gun
barrels, or in short to any piece of carburetted iron, for the purpose of more evenly
distributing the carbon. Steel produced or treated in this manner is superior to
ordinary steel, because the hydrogen employed effects not only the uniform distri-
bution of the carbon, but removes a great part of the metalloids, such as sulphur,
arsenic, and phosphor. Instead of coal, peat, or cork, I may use lignite or bituminous
shale as raw material for the manufacture of gas, and by the term fatty matter I
wish to include petroleum, vegetable oils, oleaginous grains, all sorts of tar, residues
of any fatty matter, grease, human excrements, grease-water or soap-water, resins,
naphtaline, or any other hydrocarbon oils.
What I claim is,―
1. The simultaneous manufacture of steel from wrought iron, or of fine steel
the free mathado lananihed

page_text: by heating the said articles in a retort and admitting a current of hydrogen,
substantially as described.
3. The manufacture of bricks or cakes composed as described, for the purpose of
cementing by their decomposition the articles placed in a retort, while at the same
time producing combustible gas.
In witness whereof, I, the said Paul Aube, have hereunto set my hand and
A. TAL
1
D 1001