Improved Manufacture of Calcium and other Carbides and Bye- products obtained thereby.
Year: 1897

page_text: Date of Application, 19th Oct., 1897-Accepted, 2nd Apr.,
1898
COMPLETE SPECIFICATION.
Improved Manufacture of Calcium and other Carbides and Bye-
products obtained thereby.
A communication from RICHARD MEMMO, of 24, via Napoli, Rome, in the
Kingdom of Italy, Engineer.
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of Middlesex,
Chartered 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 ascer-
tained in and by the following statement:-
This invention has for its object the manufacture of calcium and other carbides
and the construction of an electric furnace suitable for the manufacture of
carbides generally, but more particularly carbide of calcium, in which case it is
not necessary to obtain the carbide in a liquid state, which results in a great gain
of electrical energy, water-gas being obtained as a bye-product of the reaction.
In the accompanying diagrammatic drawing,
A is a crucible of pure graphite, open at the bottom and formed in the interior
in the shape of a dome, in order to form a reverberatory furnace and thus render
the discharge of the carbide produced very easy.
B is a movable bottom insulated from the rest of the furnace so as to prevent the
formation of lateral arcs between the walls and the carbons, constituted by a cast-
iron casing containing a graphite plate or bed, which may be lowered or raised
by means of a pivotted lever 7, said bottom being suitably supported and guided.
The current is introduced at this bottom through two copper wedges pressed against
the graphite plate by means of screw-bolts. The bottom is insulated from the
rest of the furnace by means of a ring of insulating and refractory material N,
which prevents contact of the graphite plate or bed and the walls of the furnace.
C is a vertical carbon (shown in section Z-V Fig. 2) connected to a carbon rod
sliding in an open space in the upper part of the casing D. When alternating
polyphase currents are used-say three phase currents the carbons (the number
of which is equal to that of the phases of the current) are arranged side by side
so as to produce with the cooperation of one point on the bottom carbon star-shaped
or, if desired, ring-shaped arcs, the bottom being in this latter case inoperative
(this arrangement is shown in the section x-y Fig. 1). Mechanism is provided
for moving all the carbons together or each separately so as to regulate the voltage
of the arcs.
D is a sheet-metal casing hermetically closed and surrounding the upper portion
of the furnace and enabling the water-gas formed during the reaction to be collected
and drawn off by means of tubes T.
E is one of the sheet-metal hoppers for charging the furnace with the mixture
of lime and carbon. Any suitable mechanism such as a valve, screw etc., may be
employed to effect or regulate the charging.
WORKING

page_text: adhesive substance so that it may be pressed into compact bricks, and dried, then
broken into small pieces and introduced into the furnace. The proportions by
weight are as follows:-
-
added to the mixture.
As soon as the crucible is charged, the arcs are produced. The carbide is formed,
and the oxide of carbon developed during the reaction mixes with the hydrogen
of the steam dissociated at this high temperature, the oxygen forming fresh oxide
of carbon with the excess of carbon in the mixture.
The furnace consequently gives as a bye-product water-gas, the properties and
the use of which are well known. It may for instance, be used for lighting, heat-
ing or the like purposes or in producing motive power etc.
When the crucible becomes full of carbide, the bottom is lowered, the block
produced removed, the furnace charged again and the operation repeated.
Although the manufacture of calcium carbide only has been described above,
it is evident that other carbides can be produced in a similar manner.
Having now particularly described and ascertained the nature of the said
invention as communicated to me by my foreign correspondent and in what
manner the same is to be performed, I declare that what I claim is :-
1. In a furnace for the manufacture of carbides, particularly of carbide of
calcium, a movable bottom insulated from the rest of the furnace so as to prevent
the formation of lateral arcs between the walls and the carbons, substantially as
described.
2. In a furnace for the manufacture of carbides, particularly of carbide of
calcium, the arrangement of carbons for forming star-shaped or ring-shaped arcs
for using alternating polyphase currents substantially as described.
3. In the manufacture of carbides, particularly of carbide of calcium, finely
pulverising the materials to be treated in an electric furnace, mixing them with
any adhesive liquid or substance, pressing them into blocks and drying the bricks
thus oained and finally breaking them into small pieces and introducing them
in this shape into the furnace, substantially as described.
4. In the manufacture of carbides, particularly of carbide of calcium, in an
electric furnace, the formation and collection of water-gas substantially as described.
5. The combination and arrangement of parts constituting the complete electric
furnace substantially as described and illustrated in the accompanying drawings.
Dated this 18th day of October 1897.
BOULT & WADE,
Agents for the Applicant.