IMPROVEMENTS IN THE MANUFACTURE OF GUNPOWDER AND LIKE EXPLOSIVE COMPOUNDS
Year: 1884

page_text: We, THORSTEN NORDENFELT of 53 Parliament Street in the City of Westminster
Civil Engineer and Captain VICTOR ALGERNON MEURLING of Christianstad,
Sweden do hereby declare the nature of our Invention for "IMPROVEMENTS IN
THE MANUFACTURE OF GUNPOWDER AND LIKE EXPLOSIVE COMPOUNDS" and in
what manner the same is to be performed to be particularly described and
ascertained in and by the following statement :-
This Invention has for its object improvements in the manufacture of gunpowder
and like explosive compounds.
At the present time in the manufacture of gunpowder it is usual to incorporate
the sulphur with the other materials by a process of grinding. This grinding is a
dangerous operation and it has to be long continued in order that the mixture of
the materials may be sufficiently intimate.
Now in place of thus producing a mechanical intermixture which after all can
only result in placing minute particles of sulphur and charcoal side by side, we
bring the sulphur to a state of solution in bi-sulphide of carbon, and in this state
we combine it with the charcoal or carbonaceous matter.
In this manner we diminish risk in manufacture, we manufacture the powder
more cheaply and obtain a power which is more even in its results.
The following is the manner in which we prefer to conduct the manufacture.
We employ charcoal, sulphur, and saltpetre of the qualities at present used in the
manufacture of gunpowder. The proportions also may be the same as now used
in gunpowder, subject to variation to some extent, and as is now usual, to adapt
the powder to the various purposes for which it is required.
We first grind the charcoal to a very fine powder, the finer the better. We
prepare the sulphur for use by dissolving it in bi-sulphide of carbon. The solution
is effected by the aid of a gentle heat in a water bath, and evaporation of the
bi-sulphide may be prevented by covering its surface with a layer of water. A
saturated or nearly saturated solution should be thus prepared.
The pulverised charcoal and the solution of sulphur in bi-sulphide of carbon are
then thoroughly mixed together in a closed vessel containing a mechanical stirrer.
When the mixture is complete the solvent is evaporated or distilled off by the aid
of a gentle heat.
The vapour or the bi-sulphide is collected and condensed so that the solvent may
not be lost. The means for this purpose such as may be are employed when this
liquid is used in the preparation of extracts and for like purposes.

page_text: When the bi-sulphide of carbon is evaporated the charcoal and sulphur remain
intimately mixed and each particle of charcoal has become impregnated with
sulphur; instead of as at present where the admixture is obtaining by the particles
of charcoal grinding and sulphur being only mechanically placed side by side.
The saltpetre is prepared for use by dissolving it in water, the solution is added
to the pulverised charcoal already impregnated with sulphur as described above
and the whole is stirred together in a mechanical mixer.
We find it advisable not to add the whole of the saltpetre at one time, but to
divide it into two or three separate quantities, and with each quantity we have
sufficient water to render the mixture with the impregnated charcoal sufficiently
fluid to pour freely.
After each admixture the water is separated by evaporation in open pans, and
heat may be applied to hasten this evaporation, but in such manner as to avoid risk
of the materials igniting as they become dry.
After the first drying operation, the material in a state of powder is again mixed
with saltpetre. solution, and is afterwards again dried as before, and so for three or
more times should it be considered desirable to divide the operation of incorporating
the saltpetre into so many operations.
When the incorporation of the saltpetre is complete it only remains to finish the
powder for use by the ordinary methods. It may be compressed into cakes or
prisms, dried, broken up, and granulated in the usual manner.
By this method the dangerous process of grinding the powder after it has been
rendered explosive by the addition of the saltpetre may be altogether avoided; or
if in any case it should be considered advisable to resort to a grinding process after
the materials have been mixed in the manner above described, the danger would
be much less than at present because of the lessened-time-daring_which the
grinding would be continued. The charcoal may also be submitted without risk to
a grinding operation after the sulphur has been incorporated with it and before
the saltpetre is added.
Although our Invention is mainly intended for the manufacture of gunpowder
from the ordinary ingredients it is also applicable to the manufacture of like
compounds in which the saltpetre is replaced by nitrate of soda or other salt capable
of furnishing oxygen to the charcoal and sulphur, and it is also applicable to
powders in which the charcoal is replaced by other matters of a carbonaceous
nature.
Having thus particularly described and ascertained the nature of our said
Invention, and the manner of performing the same we declare that what we
claim is
First. Our improvements in the manufacture of gunpowder and like explosive
compounds, consisting in dissolving the sulphur in bi-sulphide of carbon, and in
this state incorporating it with the carbonaceous matter substantially as described.
Second. Our improvements in the manufacture of gunpowder and like explosive
compounds, consisting in reducing both the sulphur and the saltpetre or equivalent
salt to a state of solution, and in this state incorporating these substances with the
charcoal or carbonaceous ingredient of the powder or explosive substantially as
described.
Date : 10th 1
+11004