IMPROVE- IN APPARATUS FOR CARBONIZING SAWDUST, BAGASSE AND SIMILAR SUBSTANCES AND FOR CONDENSING THE VAPOURS OF DISTILLATION
Year: 1884

page_text: I, WILLIAM PHILLIPS THOMPSON Fel. Inst. P.A. of N° 6, Lord Street Liverpool
in the County of Lancaster and 323 High Holborn in the County of Middlesex,
Civil Engineer do hereby declare the nature of the said Invention for "IMPROVE-
IN APPARATUS FOR CARBONIZING SAWDUST, BAGASSE AND SIMILAR
SUBSTANCES AND FOR CONDENSING THE VAPOURS OF DISTILLATION" and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
MENTS
The Drawing is a vertical section, the condenser and fan being raised so as to be
visible, they being usually placed on the ground or foundation of the plant, so that
they would be partially hidden by the rest of the mechanism if shown in their real
position.
M represents a retort which is usually made of masonry except the lower part j
which is made of iron. The retort M is preferably made of the shape shown in the
Drawing. A represents a combustion chamber built in the wall of the retort near
the top in which is a grate for burning solid fuel as shown. This chamber A
communicates with a flue E formed in the top of the retort and extending all around
the top, which flue communicates with the interior of the retort through a number of
small flues e e running through the top wall at intervals. B represents a door to close
chamber A. D represents a pipe through which a gaseous fuel is forced into the
combustion chamber, and C represents a pipe through which air is forced into the
combustion chamber, said pipe being large enough to supply more air than is
necessary to support complete combustion of all the gas which passes through
pipe D. S represents a pipe leading into the retort near the top, through which
gas is introduced directly into the upper portion of the retort.
N represents a downwardly inclined opening made through the brickwall of the
retort, closed at will by one or both of the sliding dampers J, and K represents an
opening into opening N closed at will by a plug, and intended to permit the
insertion of a poker into the retort.
a represents a hopper opening into the lower end of an inclined shaft or trunk b,
the upper end of which is connected by a similar trunk with the lower end of the
iron bottom of the retort, said hopper trunks and retort being put together by
watertight.joints.

page_text: c represents a shaft running through trunk b journaled in the upper and lower
ends thereof having on its end the driving pulley z and having attached to it screw
arms, d, and h represents a similar shaft at the lower end of the trunk g'placed in
the position shown in the Drawings and provided with a screw arm like the screw
arms on shaft c.
u represents a jacket around shaft b.
k represents an upright shaft in the lower part of the retort running through a
stuffing box and supported in a step 7. On the upper end of shaft k is a screw
arm and said shaft is driven through the pulley m and the beveled gears n.
t represents a pipe opening into the lower part j of the retort M having its inner
end covered with a grating to allow the entrance of gas, but prevent the entrance
of solid bodies. Pipe t leads into the upper part of the jacket u. y represents a
box attached to the inner end of pipe t and communicating with said pipe and with
the retort as shown, and serves to collect any liquid which may enter pipe t from
the retort. Box ย is provided with a drain pipe closed by a common faucet and
when the retort is running this faucet is left open just enough to draw off
pyroligneous acid as fast as the same accumulates and keep the level thereof
constant.
Z represents a pipe leading from the top of trunk b to a condenser to carry off
any vapour which may be generated in said trunk.
o o represent drain pipes with faucets to drain the trunks condenser etcetera.
Y represents a pipe which leads from the lower end of the jacket into a
safety-box or trap F which is partly filled with water or pyroligneous acid to seal
the end of pipe Y. Two or more retorts can be connected with one safety box,
and two pipes Y for two retorts are shown in the Drawing. The box W is
exactly like the box F. From the bottom of each of these boxes F W, leads a
horizontal pipe f to which is jointed a swinging open ended discharge pipe w
through which the wood tar, which collects at these points, is drawn off into a
suitable tank. By elevating or lowering the end of the discharge pipe w the
amount of liquid in the safety-box can be regulated and the pressure required to
open the liquid seal varied at will. G represents a pipe which leads from the
safety-box F above the level of the liquid therein to a condenser which is
constructed as shown in the Drawings, as follows. H L'are two tight vessels and
are connected by a number of pipes or tubes P which make tight joints with their
heads. The pipes P are surrounded by a tank Q which is tight at the bottom but
may be open at the top, and is provided with inlet and outlet pipes q whereby a
current of cold water may be passed through said tank, entering at the bottom and
passing out at the top. Into the top of the vessel H which forms the top of the
condenser-leads-a-pipe-R-provided-with-a-faucet by which it can be closed-and-
having on its lower end a roser by which a stream of cold pyroligneous acid
passing through said pipe enters the condenser in the form of spray. The bottom
vesgel of the condenser is provided with a drain pipe o to carry off the liquid
which accumulates therein to a storage tank, and a pipe U leads from a point
above the level of the liquid therein to a safety-box W just like safety-box F.
X represents a pipe which leads from safety box W as pipe G leads from box F,
and the end of said pipe X is connected with the suction or inlet opening of a fan
blower O, the other opening of said fan being connected to the pipe D through
which gas is forced into the combustion chamber A. The fan O is operated by any
suitable power, and a similar fan is used to force air through pipe C.
V represents a pipe which leads from the lower part of the retort, rises to the
level of the lower side of pipet and discharges into a tank placed under its end,
it serves to draw off the tar which accumulates in the lower part of the retort as
fast as the level of the liquid in the retort rises to the height of pipe t. It is
provided with a nipple v in which is a faucet by which pipe V can be drained.
PP represent toothed bars pivoted at one end to the lower part of the retort,
and 88 represent push-rods which pass, through the sides of the retort, and are
pivoted to the loose ends of the toothed bars so that the angle of said bars may he

page_text: varied. The Drawing shows the toothed bars as pivoted at their opposite ends but
this is not material as they may be both pivoted at the same end. They aid in
supporting the material in the retort.
The operation of this Invention is as follows:-
:
The retort M is filled with the material to be carbonized nearly to the level of the
pipe S, and the lower part of the retort is filled with liquid to the level of the
dotted lines to form a liquid seal. A fire is now started on the grate in combustion
chamber A, and by means of fan and similar fans properly connected with the
several pipes gas is forced through pipes D S and air through pipe.C.
The gas
which passes through pipe D becomes ignited and burns in chamber A and the hot
products of combustion pass through flue E and apertures e e into the retort. As
pipe C supplies more air than is necessary to support combustion in chamber A
enough air passes through flue E and aperture e e to support combustion of the
gas which passes through pipe S and this burns in the upper part of the retort.
The result is that the top of the retort becomes intensely hot, and the upper
portion of the material in the retort becomes carbonized by the heat radiated from
the top of the retort and the radiant heat from the flame without coming in
contact with any flame. When the upper portion of the material is sufficiently
carbonized a poker is inserted through openings K N, the charcoal drawn down
on damper J, opening K closed, and damper J opened to allow the charcoal to fall
into a tank.
Fresh material is introduced into the hopper a, is elevated by the screws d on
shaft c, falls to the bottom of trunk g, whence it is forced by the screw-shaft h into
the bottom of the retort, and passes along the inclined side thereof until it is
caught and forced upwards by the screw i on shaft k. By introducing fresh
inaterial into the hopper only as fast as the upper surface of the material in the
retort is carbonized, the process becomes constant.
The toothed or ratchet bars assist in sustaining the mass of material in the
retort.
When it is desired to reduce the amount of heat in the retort the pipe S may be
closed, or the apertures e e may be closed by ordinary dampers, and the hot gases
in flue E led off to a chimney.
The products of combustion in the top of the retort, and the vapors given off in
carbonization cannot escape except by passing down through the material in the
retort, and in doing this a portion of the heat in said gas is communicated to the
uncarbonized material, thus partly preparing it for carbonization. On reaching
the lower part of the retort the gas passes off through pipet goes through jacket u,
thus warming the material which is passing through trunk b, and passes through
pipe Y into safety-box F. It bubbles up through the liquid in safety-box F and
passes through pipe G into the upper vessel H of the condenser, where it comes in
contact with a spray of cold pyroligneous acid coming through pipe R and rose 1,
and much of the pyroligneous acid in said gas is condensed partly by the consequent
reduction in temperature and partly by its chemical affinity for the cold acid. The
gas passes through the pipes of the condenser being further condensed by the
water in tank Q, and thence into the lower vessel 7 whence the condensed portion
is drawn off through a pipe o into a storage tank, while the uncondensed gas passes
through pipe U, safety-box W and pipe X to the fan O, which forces it into the
combustion chamber through pipe D.
The tar which condenses in the retort falls to the bottom thereof and rises in
pipe V until it overflows said pipe and runs into a tank placed to receive it. The
tar which condenses in either of the safety-boxes passes off in like manner through
the pipes w.
In carbonizing sawdust by the means. shown herein the material is subjected to
pressure when forced upwards by the screw i and this tends to cause it to carbonize
in lumps like ordinary charcoal.
The passage of the hot vapours of distillation through the mass of uncarbonized
material in the retort partially condenses said vapours.

page_text: Having now particularly described and ascertained the nature of the Invention
as communicated to me, and in what manner the same is to be carried into effect,
I declare that what I claim is:
1st. A retort for carbonizing wood, sawdust or similar substances, having in its
top a flue communicating through apertures with the interior of the retort, a
combustion chamber communicating with said flue, an air pipe and a gas pipe
leading into said combustion chamber, and a gas pipe leading into said retort near
its top, substantially as described.
2nd. In the carbonization of wood, a retort within which the wood is supported
in combination with a box located in the bottom of the retort for containing.
pyroligneous acid, and a pipe V leading from the bottom of the box or retort
upwardly to the level of the acid in said box or retort, for drawing off the tar
accumulating in the bottom of the retort, substantially as described.
3rd. In combination with the retort M, the toothed bars p p provided with push
rods & s, substantially as shown and described.
4th. The combination of a retort having a pipe at or near its top for entry of
hot vapour, with mechanism for introducing the substance to be distilled at the
bottom of the retort, and forcing the same upwards as the distilled solid material
is removed from said retort, whereby distillation is effected from above upon a mass
of material raised up within the retort to the source of heat.
5th. The herein described method of partially condensing the vapours resulting
from carbonizing the upper portion of a mass of material contained in a retort,
consisting in passing such vapours through the uncarbonized portion of the
material in said retort.
6th. The combination of the screw i, retort M, trunks 9 b, and screws d h,
substantially as and for the purposes set forth.
7th. The combination of the jacket u and trunk b, with the exit pipe t of the
retort, whereby a preliminary distillation of the material is effected by the hot
vapours issuing from the retort.
8th. The combination of the jacketed trunk b, hopper a, trunk g, and screw d,
substantially as shown and described.
9th. In combination with the retort, the safety-box F having the swinging
discharge pipe f, and connected by the pipe G with a condenser, substantially as
shown and described.
10th. The condenser herein described, having vessel H with pipes G R, and
vessel having the drain pipe and faucet o, and pipe U, said vessels being connected
by pipes P substantially as shown and described.
11th. The herein described process.of.condensing-a-portion-of-the-vapour-arising
from the distillation of wood, consisting in bringing said vapour in contact with a
spray of cold pyroligneous acid, whereby condensation is effected by the chemical
affinity of the acid and vapour as well as by reducing the temperature of said
vapour.
Dated this 16th day of June 1884.