IMPROVEMENTS IN TREATING ORES OF ZINC, AND IN THE APPARATUS EMPLOYED THEREIN
Year: 1860

page_text: LETTERS PATENT to Albert Accarain, Managing Director of the Société
de Dolhain, of Limbourg, in the Kingdom of Belgium, for the Invention
of "IMPROVEMENTS IN TREATING ORES OF ZINC, AND IN THE APPARATUS
EMPLOYED THEREIN."
Sealed the 14th August 1860, and dated the 16th April 1860.
PROVISIONAL SPECIFICATION left by the said Albert Accarain at the
Office of the Commissioners of Patents, with his Petition, on the
16th April 1860.
I, ALBERT ACCARAIN, Managing Director of the Société de Dolhain, of
Limbourg, in the Kingdom of Belgium, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN TREATING ORES OF ZINC, AND IN THE
APPARATUS EMPLOYED THEREIN," to be as follows:-
This Invention of improvements in treating ores of zinc, and in the appa-
ratus employed therein, consists in treating zinc ores in a cupola furnace or
oven in such a manner that the inconveniences usually experienced in working
with this kind of furnace are avoided. I consider that many of the obstacles to
the proper working of the reducing process in the ordinary furnaces arise from
the fact that the zinc vapors when escaping are commingled with too large a
volume of the gaseous products arising from the combustion of the fuel, and

page_text: therefore they are condensed with difficulty. My object, therefore, has been to
reduce the volume of these gases to the minimum, or what comes to the same
thing, to diminish the quantity of fuel required to treat a given weight of ore.
To attain this object two means are employed, 1st, the fuel is heated before
being supplied to the apparatus; 2nd, the residuum is taken away in a solid
or pasty state, instead of being liquefied in the apparatus.
lined
The cupola or smelting oven is constructed of brickwork or masonry,
It is placed
with fire-clay, and enclosed within a wrought-iron casing.
vertically, and is raised on pillars or walls, so that a moveable box, which
forms the bottom, may be run on rails underneath the open bottom of the
furnace, which is open at top for the convenience of charging, but may be
closed by a moveable cover. Openings are made near the upper end to allow
the zinc vapors and gases from the fuel to escape, and be collected in tho
ordinary manner. Openings to admit air are made in the moveable bottom at
the lower part of the furnace, and other openings are made in the fixed portion
of the lower part of the furnace to receive grate bars to support the fuel and
charge of the furnace. The moveable bottom is made of wrought iron, lined
with fire-clay, and if required may be provided with wheels or rollers to run
upon rails, or otherwise provided with contrivances to facilitate the operation of
moving it to and fro from under the furnace. Two or more moveable boxes or
bottoms will be required for every furnace, so that when one is drawn away
another may be immediately substituted in its place.
In carrying out the Invention the furnace or oven should be first charged
with fuel, which must be ignited so as to get up a proper heat before the zinc
ore is added. When the fuel has become well lighted, and some of the gases
have passed off, the oven will be found hot enough to add tho ore. Sometimes
it is proposed to heat the ores before putting them in the reducing furnace.
The fuel may also be added from time to time in a red hot or incandescent
state, and hot air may be supplied to assist combustion. All these plans have
for their object to diminish the quantity of fuel actually required to reduce the
ores. As the zinc is volatilized and passes off through the openings above, the
residue or slag will descend in the furnace, and by withdrawing the grate bars
it will be allowed to fall into the moveable box, which forms the bottom of the
furnace, and it may then be removed.