Manufacture of Charcoal.
Year: 1898

page_text: Manufacture of Charcoal.
I, DOMINIQUE ANTOINE CASALONGA, of 15, Rue des Halles, Paris, France,
Engineer, 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:-
It is a great advantage before inserting wood for making charcoal into the
distilling and carbonizing retorts or stoves, to remove from this wood the greatest
possible portion of its natural moisture. For this purpose I employ according
to this invention an apparatus for continuous and systematic working which com-
prises an annular gallery or passage (hereinafter called a gallery) provided with a
line or track of rails also annular, upon which runs, at a low speed, a train
composed of open wagons coupled together and loaded with the wood to be dried,
and moved by means of an annular toothed rack to which they are fixed or by any
other suitable means. At a certain point of this gallery, inside the circle bounded
thereby, or outside the same, there are arranged at a slight distance from one
another:
(1) The fireplace or fireplaces in which the fuel is burned by means of which
the drying is effected;
(2) Platforms which are connected to the ground by inclined planes and on
which the loading and discharging of the wagons is effected;
(3) An underground way for affording access to the centre of the circle; and
(4) A draught-producing apparatus, such as a fan or chimney, which discharges
into the atmosphere the current of air and gas that is laden with vapour and has
served to effect the drying.
The wagons, in which the wood is placed and piled up, are open so as to allow
the mixture of air and gas to circulate freely through the pieces of wood. The

page_text: wagons combine to form a continuous annular train which is completely sheltered
or covered in by the gallery, which has, however, a section sufficient to allow of
the passage of the drying current. This gallery is, however, open at a certain point
opposite the loading and discharging platforms so as to facilitate the operations
of loading and discharging. Further, the bottom of each wagon is preferably
inclined, either to one side only or to both sides, from the axis, and the lower
part of each side wall of the wagon is formed with an opening extending the
entire length, through which the wood can slide or roll and thus leave the wagon,
when a hinged door which closes this openings is raised. This door is closed as
soon as the wagon, after being emptied and reloaded, moves into the gallery for
the purpose of travelling around the same at a low speed. The dried wood having
been discharged, and the side doors having been let down to close the correspond-
ing openings and fixed, the wagon that has been previously discharged is loaded
with green wood, and so on, whilst the annular wood train travels at a very low
speed, being propelled along its track by means of a toothed wheel gearing into a
toothed rack, or by other suitable means.
The wagons loaded with green wood travel in the gallery in a direction opposite
to that of a hot drying current, which is composed of a mixture of air and hot
gases due to the combustion of the fuel being burned on the grate or grates. This
current is produced by the drawing or forcing action of one or more fans or blowers
or by the draught of a central uptake or chimney situated near the fireplace or
fireplaces. Between the chimney or the fan or fans and the fireplace or fireplaces,
there are situated at a suitable height the loading and unloading platforms, and
also the underground way. The gases of combustion produced on the grate or
grates are led into a mixing-chamber which communicates by means of apertures
(provided by dampers) with the outer air, which is drawn or forced into the said
chamber to a quantity sufficient to lower the temperature of the mixture to a
degree at which it cannot ignite or injure the wood to be dried.
Having been brought to this temperature the mixture is discharged into the
gallery through apertures opposite which are situated, and are passing slowly, the
wagons carrying the hottest and most highly dried wood, which is then com-
pletely dried by contact with the gases of the said current. This wood is then
immediately traversed by a current of air that cools it so as to recover therefromi
the heat and which enters into the mixture. After that, the wagon arrives in
front of the platforms, where the gallery is open laterally and at the top; the
doors are opened and the wood is discharged; then the same doors are shut again
and the wagon is reloaded, and so on.
A transverse partition arranged around and under the wagons prevents the
air and gases of combustion, coming from the fireplace or fireplaces and the
mixing chamber, from passing direct to the fan or chimney. Baffles are arranged
at intervals of distance in the gallery in order to cause the gases to travel in the
direction necessary for proper drying.
Supplementary fireplaces, fixed or movable, may be arranged against the
gallery for the purpose of raising the temperature of the current of air at any
desired point, whilst getting the plant ready, or during the working.
The gallery may be constructed partly of brickwork, partly of plaster slabs, and
partly (particularly at the parts that are in the vicinity of the opening for dis-
charging into the atmosphere, where the temperature of the gaseous current is
lowest) of wood covered with a layer of asbestos.
The external air that is mixed with the hot gases of combustion in order to
lower the temperature sufficiently, or is used to support combustion in the fire-
place or fireplaces, may come from a heat recuperator or regenerator which would
be placed in the passage or flue that conducts the current of air or cooled gases to
the chimney or the exhausting van, the arrangement being such as to promote or
bring about the condensation, in this flue or passage, of a part of the vapour or
steam carried along, and, consequently to effect the recovery of part of the heat
that would otherwise escape into the atmosphere.

page_text: Figs. 1, 2 and 3 of the accompanying drawings illustrate an apparatus or plant
according to this invention, Fig. 1 showing part of the gallery longitudinal
section along its axis and two of the wagons in elevation, Fig. 2 showing the gallery
and a wagon in section, and Fig. 3 being a sectional plan of a portion of the
gallery showing the fireplace and the mixing-chamber, the place where the heat
is taken up from the dry and hot wood, the platforms, the chimney, and the
recuperator.
A are openwork wagons that travel in the gallery B in the direction indicated by
the arrow f, which is opposite to that, indicated by the arrow f, of the current
of air and gas; aa are doors for unloading. C is the mixing chamber; D, E,
and F are apertures, furnished with dampers, respectively for the gases of com-
bustion from the fireplace, the hot air from the apertures G and the recuperator,
and the supplementary air from the external atmosphere. G are apertures for
leading air to the hot wood, whence it passes through the aperture E, into the
mixing-chamber C; g g are apertures, provided with dampers, for leading the
mixture of air and gases into the gallery. H are openings for loading and unload-
ing, which is done upon platforms I. J is a chimney with or without a blower at
its base. K is a heat-recuperator traversed on the one hand by the moist current
on its way to the chimney, and on the other hand by air from the external
atmosphere on its way to the fireplace to support combustion or to the mixing-
chamber C to either of which places it travels through a passage L. N is a
perforated thin iron sheet forming the bottom in the shape of a roof, of each wagon.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. An apparatus or plant for systematically and continuously drying wood for
the manufacture of charcoal, before inserting it into the distilling retorts, com- .
prising a gallery having apertures close to each other for loading and unloading
in the vicinity of a fireplace and a chimney or its equivalent, and provided with
a track of rails upon which run openwork wagons coupled together and loaded
with the wood to be dried and moving slowly and against a current of hot gases,
which after being loaded with moisture, is discharged into the external atmosphere
by the action of the chimney or its equivalent, substantially as hereinbefore
described.
2. Apparatus or plant arranged and worked as specified in the preceding claim,
in which the drying-current is produced in a mixing-chamber wherein the pro-
ducts of combustion from a fireplace or fireplaces are mixed with sufficient air
from the external atmosphere to produce a mixture of such a temperature as to
be incapable of igniting or injuring the wood but yet to be adapted to dry it as
well as possible, substantially as hereinbefore described.
3. An apparatus or plant arranged and worked as specified in the preceding
claims, in which the bottom of each wagon is formed by a perforated iron sheet
inclined towards apertures, which extend for the entire length of the wagon in
the lower portions of its side walls and which are closed by doors suspended from
horizontal hinges, substantially as and for the purpose set forth.
4. An apparatus or plant arranged and worked as specified in the preceding
claims, in which the dried and hot wood, before being unloaded, is traversed
by a current of air that cools it, so as to recover heat therefrom, and which after-
wards passes either into the fireplace or fireplaces to support combustion or into
the mixing-chamber, substantially, as herein before described.
5. An apparatus or plant arranged and worked as specified in the preceding
claims, in which the drying current loaded with moisture, before being passed
into the external atmosphere, traverses a recuperator through which also passes
a current of air that takes, heat from the said drying-current and afterwards passes
into the fireplace or places to support combustion or into the mixing-chamber.

page_text: 6. My improved apparatus or plant for drying wood for the manufacture of
charcoal constructed, arranged, and worked as hereinbefore described with
reference to and shown in the accompanying drawings.
Dated this 7th day of May 1898.
F. WISE HOWORTH,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.