Improvements in and relating to Processes and Apparatus for Disintegrating Vegetable Substances for the Production of Fibres therefrom.
Year: 1891

page_text: Date of Application, 31st Mar., 1891-Accepted, 2nd May, 1891
COMPLETE SPECIFICATION.
Improvements in and relating to Processes and Apparatus for
Disintegrating Vegetable Substances for the Production of Fibres
therefrom.
I, ALEXANDER SELKIRK, residing at Number 31, North Pearl Street, in the
City and County of Albany, and State of New York, one of the United States of
America, Manufacturer, do hereby declare the nature of my said invention and in
what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement, reference being had to the accom-
panying drawings, in which :-
Figure 1, is a side elevation of my said apparatus as arranged for use;
Figure 2, is a vertical central section of the digesting and liquor heating
vessels ;
Figure 3, is a horizontal section of the same upon line, -, of Figure 2;
Figure 4, is an enlarged vertical section of the connected portions of the wall
of the digesting vessel and the reticulated diaphragm which form the annular
liquor chamber;
Figure 5, is a horizontal section of the same upon line, a', of Figure 4.
My invention has for its object the treatment of woods, straws, grasses, and
other kinds of vegetable substances so as to produce from the same a fibre which
shall be adapted for use in the manufacture of paper and other like articles, and to
such end my said invention-
Consists, principally in the method employed for separating the fibre from the
substance with which it is combined, substantially as and for the purpose herein-
after.specified.
It consists, further, in the mechanism used for the carrying of the method into
practice, substantially as and for the purpose hereinafter shown and described.
In the use of my invention, I employ a digesting vessel, A, which is constructed
from iron or steel, in the form of a cylinder with semi-spherical ends or heads, A¹,
and, A2, and has such strength as to enable it to safely resist a pressure of from
eighty (SO) to one hundred and twenty (120) pounds per square inch.
Within the upper head, A', is provided an opening, u, through which the material
to be treated may be introduced into the vessel, and such opening or manhole is
enclosed by means of a cover, B, that is preferably, fastened in place by bolts or
other like devices. From the said opening, a, a cylindrical plate of reticulated
sheet-metal, C, extends downward for a short distance and at its lower open end is
connected with an annular plate, C¹, of similar material that extends horizontally
to the wall of the vessel, as shown, which parts thus arranged, operate to form
within the upper end of said vessel an annular chamber, C2, that has communication
with the space within and below, through the openings in its inner and lower walls.
A removable plate or valve, D, fitted to and adapted to rest upon a ledge or seat, c,
at the lower end of the cylinder, C, operates to close the same to the direct passage
of liquids. Said plate or valve may be readily withdrawn when said cover, B, is
removed, by means of a handle, d, that is connected with and extends upward from
the centre of the former, if desired said valve may also be formed from reticu-
lated metal.
At a short distance above the lower end of the vessel, A, is provided a reticu-
lated plate or diaphragm, E, which extends between the walls of the same, pre-
ferably, at about the angle shown, is suitably supported and forms at and from the
lower end of said vessel a chamber, F. Upon a line with the upper face, at the
lowest portion of said diaphragm an opening, a, is provided within the wall of
the vessel, A, through which the contents of the same may be blown out, when
desired. Said opening is enclosed by a valve, which is not shown.

page_text: Within the interior of the vessel, A, preferably, at cach side of its longitudinal
centre, is an annular chamber, C, which is formed by means of a reticulated
plate, H, that has the form of a cylinder which has a less diameter than the interior
of said vessel, and at its ends is connected with the latter by or through rings, h,
and, , that are interposed between the same. Other rings,, and, h', are placed
between and secured to said plates at suitable points between the ends of said
plate, H, and operate to strengthen and support the latter. The cpenings in said
plate, H, are preferably, about one eighth of an inch in diameter and arranged
about one-fourth of an inch apart. The rings, h, and, h, are preferably, con-
structed from L-shaped iron, and the rings,, and, ', from T-shaped iron, but
other forms may be used, if desired, as their only office is to support and strengthen
the plate or diaphragm, H, against lateral pressure. Said intermediate rings are
each provided with openings, ², and, 2, through which communication is had
between the parts of the chamber, G.
In the use of the digesting vessel, A., it is intended that its interior from the
diaphragm, E, to or near its upper end shall be filled with material to be fiberized
and a cooking liquor then introduced simultaneously into each end chamber, C³,
and, F, and such liquor then drawn off through the chamber, G, having meanwhile
been compelled to thus pass through such material from each of its ends to its
centre.
To secure such results a pipe, 1, and a pipe, I', are connected respectively, with
the upper and lower ends of the digesting vessel, A, and from thence extend to and
are connected with the discharge opening of a pump, K, while a third pipe, L.
extends between the suction opening of such pump and the chamber, G. When
now, the pump is operated, the liquor is delivered under pressure, into each of the
chambers, C and, F, and is drawn from said chamber, G, and can be made to pass
through the material being operated upon and around the double circuit as rapidly
or slowly as desired, by varying the speed of said pump. While said pipe, is
preferably, connected with the chamber, C, through the cylindrical diaphragm, C,
it may if desired, be connected directly with said chamber, but in either case the
result is that liquor forced through said pipe is discharged downwardly in small
streams upon the solid contents of the digester.
The action of a digesting liquor is materially improved by heat and in order that
any desired temperature may be given to such liquor, I arrange between the
digester and pump, preferably, between the chamber, G, and said pump a heater
which externally has the form of a short cylinder, M, with rounded or semi-
spherical upper and lower ends, m, and, m', respectively. Said heater is preferably,
located between the chamber, G, and pump, K, as before stated, and has the pipe, L,
connected to or with its ends so that it thus forms part of said pipe and of the
circulatory system.
Within the shell, M, near each end, is secured a head, m², that resembles the
flue shut of a boiler and is provided with a number of round openings that each
contain one end of a flue or tube, m³, which is secured within the corresponding
opening in the opposite head, m². The heads, m², and, m², divide the interior of the
heater, M, into a central chamber, m', and two end compartments, m³, and, m
which latter are connected by the tubes, m³, and, m³, while said central compart-
ment, m, is cut off from and forms no part of the circulatory system, but being
connected with a steam supply and filled with steam, heat from the latter will
pass through said heads and tubes and will be taken up by a liquid passing through
the heater. While steam is the heat transmitting agent preferably employed with
the said heater, air, gas, water, or any other similar agent may be substituted
therefor, if desired.
The diameter and length of the heater and the number and lengths of the tubes
are governed by the capacity of the digester and the quantity of liquor to be
heated and the temperature to be given to the same may be varied at will, but in
order that there may be an even distribution of the liquor through such tubes,
there is secured within one end of each of the same, a metal plug, m', which is

page_text: provided with a central opening and operates to reduce the capacity of such tube
at such point to pass the liquor. The openings in said reducing plugs have sub-
stantially the same diameters and their aggregate areas are about equal to the
area of the pipe, L, so that the liquor passing through will be evenly distributed to
said tubes and in passing through will be uniformly heated, while without said
plugs, such liquor would pass rapidly through some tubes and slowly through others,
and the efficiency of the heater be thereby lessened. When the volume of
liquor to be heated is considerable and is to have an upward movement within the
heater, the plugs are preferably set into the upper ends of the tubes, but when
the volume of liquor to be heated is comparatively small and its passage com-
paratively slow, said plugs should be placed within the lower ends of said tubes.
While the heater described is preferably employed, if desired, any other form of
construction may be used, or any other means employed for giving to the liquor the
required temperature. The pipe circuit is provided with the necessary and usual
check and other valves to enable the flow of liquor to be controlled, but as they
are well known expedients and are to be used and operated in the usual manner, no
further description of them is required.
In connecting the digester, pump and heater, any desired arrangement of pipes
can easily be made so that the whole or any portion of the digesting liquor may
be caused to pass through said heater, and the temperature of such liquor as it
enters either end of said digester may be separately and independently regulated,
or said heater entirely cut out of the circuit, should occasion require.
When the substance to be treated is finely subdivided as wood when in the form
of saw-dust, or the broken hulls of cotton seeds, the perforated wall of the
discharge chamber, G, is preferably covered with fine mesh wire cloth and the
same suitably secured in place. Said chamber by vertical extension, is given such
capacity as is required in order to secure a free passage for the liquor and prevent
the draught of the pump from clogging the passages in the diaphragm, while in
consequence of the large area through which said liquor passes into said discharge
chamber, strong currents at such point are avoided and the movements of such
liquor through the material will be uniform and free from liability to obstruction.
In the use of my invention, the digester is filled with raw material, properly
sub-divided, and then closed tightly,..after which the cooking liquor, suitably
heated, is introduced into the end chambers and withdrawn from the central
chamber and kept in circulation through the material and through the heater until
said material has been reduced to the desired fibrous condition, after which the
digesting liquor is drawn off and the disintegrated material then blown from the
digesting chamber through the valve discharge opening. The degree of heat and
pressure within said digester and the rapidity of the circulation of the digesting
liquor are governed by the nature of the substance being fiberized and vary
considerably.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed. I declare that what I
claim is―
1. In an apparatus for disintegrating vegetable substances, a digesting vessel
which is provided with a digesting chamber, an annular, centrally located liquor
chamber, and a liquor chamber within its lower end, which chambers communicate
through perforated plates, in combination with a pump, a pipe extending between
and connecting the inlet of the pump with the annular liquor chamber, pipes
extending between and connecting the outlet of said pump with the ends of the
digesting vessel and a heating mechanism that is located within the said pipe
circuit, outside of said digesting vessel and is adapted to heat the digesting liquor
during its passage from said annular chamber through said pipe circuit and into
said vessel, substantially as and for the purpose specified.
2. In an apparatus for disintegrating vegetable substances, a digesting vessel
which is provided at or near the longitudinal centre of its digesting chamber with

page_text: a liquor separating and discharging chamber that is formed by the wall of said
vessel and a cylindrical perforated plate which is arranged concentric with said
wall and is secured thereto by solid end rings, and centrally arranged supporting
rings that have communicating openings or ports, substantially as and for the
purpose shown.
3. In an apparatus for disintegrating vegetable substances, a digesting vessel
which at or near the longitudinal centre of its digesting chamber is provided with
an annular liquor separating and discharging chamber that communicates with said
digesting chamber through a perforated plate and by means of annular plates
having lateral openings or ports, is divided into two or more communicating
sections, substantially as and for the purpose set forth.
4. In an apparatus for disintegrating vegetable substances, a digesting vessel
which has a digesting chamber and digesting liquor receiving and discharging
chambers separated therefrom by perforated plates, a pipe circuit that connects
said liquor chamber, and a pump for producing a circulation of the digesting
liquor, in combination with a heating mechanism that is arranged within the pipe
circuit and is composed of a cylindrical shell having within its ends liquor chambers
which communicate by means of tubes that are contained within and pass through
an intermediate steam-chamber, substantially as and for the purpose shown and
described.
5. In an apparatus for disintegrating vegetable substances, a mechanism for
heating a digesting liquor consisting of a cylindrical casing containing two liquor
chambers, an intermediate steam chamber and tubes which pass through the
latter and furnish communication between, said liquor chambers, in combination
with a digesting vessel and with piping which extends between and connects said
vessel with said heating mechanism, substantially as and for the purpose shown.
6. In an apparatus for disintegrating vegetable substances, a mechanism for
heating a digesting liquor consisting of a casing containing two liquor chambers,
an intermediate steam chamber, tubes that pass through the latter and furnish
communication between said liquor chambers and hollow thimbles which are
placed within the ends of said tubes and operate to reduce the area of the openings
in the same, substantially as and for the purpose shown.
Dated this 31st day of March 1891.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.