The elevator is set in motion by the simple maneuver of the gearing
lever, P, and when this has been done all the other motions are effected
automatically.
_The Animal Black Furnace_.--This consists of a masonry casing of
rectangular form, in which are arranged on each side of the same
fire-place two rows of cast-iron retorts, D, of undulating form, each
composed of three parts, set one within the other. These retorts, which
serve for the revivification of the black, are incased in superposed
blocks of refractory clay, P, Q, S, designed to regularize the
transmission of heat and to prevent burning. These pieces are kept in
their respective places by crosspieces, R. The space between the retorts
occupied by the fire-place, Y, is covered with a cylindrical dome, O, of
refractory tiles, forming a fire-chamber with the inner surface of the
blocks, P, Q, and S. The front of the surface consists of a cast-iron
plate, containing the doors to the fire-place and ash pan, and a larger
one to allow of entrance to the interior to make repairs.
One of the principal disadvantages of furnaces for revivifying animal
charcoal has been that they possessed no automatic drier for drying the
black on its exit from the washer. It was for the purpose of remedying
this that Mr. Schreiber was led to invent the automatic system of drying
shown at the upper part of the furnace, and which is formed of two
pipes, B, of undulating form, like the retorts, with openings throughout
their length for the escape of steam. Between these pipes there is a
closed space into which enters the waste heat and products of combustion
from the furnace. These latter afterward escape through the chimney at
the upper part.
In order that the black may be put in bags on issuing from the furnace,
it must be cooled as much as possible. For this purpose there are
arranged on each side of the furnace two pieces of cast iron tubes, F,
of rectangular section, forming a prolongation of the retorts and making
with them an angle of about 45 degrees. The extremities of these tubes
terminate in hollow rotary cylinders, G, which permit of regulating the
flow of the black into a car, J (Fig. 1), running on rails.
From what precedes, it will be readily understood how a furnace is run
on this plan.
The bone-black in the hopper, A, descends into the drier, B, enters the
retorts, D, and, after revivification, passes into the cooling pipes, F,
from whence it issues cold and ready to be bagged. A coke fire having
been built in the fire-place, Y, the flames spread throughout the fire
chamber, direct themselves toward the bottom, divide into two parts to
the right and left, and heat the back of the retorts in passing. Then
the two currents mount through the lateral flues, V, and unite so as to
form but one in the drier. Within the latter there are arranged plates
designed to break the current from the flames, and allow it to heat all
the inner parts of the pipes, while the apertures in the drier allow of
the escape of the steam.
By turning one of the cylinders, G, so as to present its aperture
opposite that of the cooler, it instantly fills up with black. At this
moment the whole column, from top to bottom, is set in motion. The
bone-black, in passing through the undulations, is thrown alternately to
the right and left until it finally reaches the coolers. This operation
is repeated as many times as the cylinder is filled during the descent
of one whole column, that is to say, about forty times.
With an apparatus of the dimensions here described, 120 hectoliters
of bone-black may be revivified in twenty four hours, with 360 to 400
kilogrammes of coke.--_Annales Industrielles_.
* * * * *
[Continued from SUPPLEMENT, No. 330, page 5264.]