DISGRA OF VEGETABLE TISSUES
Year: 1884

page_text: I, JOHN ADAMS SOUTHMAYD, Manufacturer, of Elizabeth, in New Jersey, one
of the United States of America, do hereby declare the nature of my invention
for THE DISINTEGRATION OF VEGETABLE TISSUES, and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement :-
This invention consists in an improved process for reducing vegetable tissues to
fine fibres, for the production of paper pulp, and also in a special apparatus for
practicing the same. The chemical processes heretofore used have generally caused
the destruction of a considerable portion of the tissues, during the reduction of the
harder parts of the fibre; and my invention is primarily intended to obviate this
loss or destruction of material, by arresting the chemical action when the
disintegration is but partly effected, and completing the disintegration by a
violent expulsion of the tissues and their contained fluids from the boiling vessel.
I am thus enabled to reduce the raw material in a single vessel, and in a single
continuous operation, to the condition of pulp ready in all respects for use in
making paper except washing. In the drawing, Fig. 1 exhibits, in section, a boiler
fitted with the necessary attachments for this purpose; and Fig. 2 is a side view of
the outlet cock B. A is the shell of the boiler, formed of curved tapering shape at
the bottom, to discharge the mass with facility through the cock B, which is
represent
nted in the drawing as open and with an aperture of the same size as the
discharging pipe, to cause no obstruction to the discharge.
C is a
P is a man-hole for inserting the fibres and for admission to the boiler.
vent or blow off pipe with cock C. D, D, are steam pipes inserted near the top of
the boiler and carried downward to a point near the discharge outlet O; the
cocks D' serving to regulate the admission of steam. E is a pipe inserted in the
boiler near the bottom to remove the fluid from the charge; and is provided with
a cock E e is a screen over the inner end of the pipe, and fa pipe to blow steam
over the screen and clear the fibres away from it. The outer end of the pipe is
shown curved downward over a tank G'. K are test pipes inserted at different
levels in the side of the boiler; L being cocks in the same; and M a closed
chamber into which the pipes are conducted. N are steam pipes inserted into the
boiler at any point and terminated opposite the mouths of the pipes K; N' are
cocks in the same.
My method of operation with a boiler of this construction is as follows: a charge
of the tissue is inserted in the boiler through the man-hole with the proper
proportion of caustic liquor, using for the harder tissues about 6 degrees Baume,
and for the softer ones about 3 to 4 degrees Baume; and the outlets all being
closed, steam is introduced through the pipes D, and the contents of the boiler kept
at the pressure of 75 to 150 lbs, with a corresponding temperature, for three or
four hours.

page_text: The liquor may be introduced from a tank G, by a funnel H and cock I, or
inserted through the man-hole. The steam being introduced at the bottom of the
boiler, tends to raise the mass inside the same and thoroughly agitate the whole
charge. The weight of the charge however, obstructs the circulation, and the
operator therefore occasionally opens the vent cock C¹, and suddenly blows off
steam. This secures a sudden flow of steam from the inlet pipes D; and a violent
agitation of the mass. The progress of the disintegration is tested from time to
time, by suddenly opening one of the cocks L, a portion of the contents is violently
ejected into the box M, and may be gathered and examined with the fingers, a
magnifier and by other means, to test its condition.
To discharge such sample more forcibly, the operator first opens one of the
cocks N¹ to jet steam toward the mouth of the test pipe K. The agitation of the
contents by the cocks C' is performed to secure an equal effect upon the fibres at
all points in the boiler, and the boiling is continued until the gums are sufficiently
softened to permit of ready disintegration by mechanical means, when in such
heated state. The final disintegration may then be effected, without bleaching, by
opening the outlet cock B and discharging the entire mass violently from the
boiler; the current of steam from the pipes D aiding materially, besides the
expansive force of the steam within the tissues themselves. Such steam tends to
rupture and separate all the fibres and to reduce them to a soft pulp whether the
mass be discharged into space or against a wall.
For both disintegrating and bleaching the fibres, before discharging from the
boiler; chlorine may be used in the following manner; and the pulp be thus
ready for the manufacture of white paper without any succeeding operations. The
pressure may be wholly or partly discharged from the boiler by the blow off
cock C, and the alkaline liquor then drawn off by the pipe E, the steam being
blown across the inner side of the screen when the fibres become packed against
the same, by the jet pipe f, which is flattened at its end to spread the steam over
While drawing off
the screen, and is provided with a cock g outside of the boiler.
the alkaline liquor, a charge of clean water is preferably introduced through the
funnel H and cock I, from the tank J, thus discharging the dissolved inatters more
effectually from the interior of the boiler. I then introduce a liquor containing
chlorine from the tank through tho funnel H and cock I, in such quantity as to fill
the boiler quite full; as it is obvious, that heat would drive all the chlorine gas
out of the tissues were an unfilled space left at the top of the boiler; and its
effect under heat and pressure would thus be largely lost, I have discovered
that, owing to the acrid effects of the chlorine under these conditions of heat and
pressure; a very small quantity of chlorine, less than half of that required when it
is used for bleaching purposes with cold solutions; operates as a disintegrating
agent upon the softened gums in the tissues and effects a further disintegration by
destroying and removing a part of such gums.
To avoid the washings that are commonly required to free the fibres from the
chlorine; I draw off sufficient of the liquor containing chlorine, by the pipe E, to
form an empty space in the top of the boiler, discharging the liquor preferably into
cold water in the tank G¹ so as to retain the gas in the solution to utilize
it again.
I then boil the tissues to drive out all the gas contained in the same, the gas
accumulating in the upper part of the boiler, and being drawn off by the pipe C¹ and
preferably discharged into cold water to preserve it for future use. The boiling is
then continued until proper tests show that the chlorine is entirely removed; when
the remainder of the liquor and the contained tissues may be simultaneously
discharged from the boiler, and finally disintegrated by a violent expulsion
through the cock B. The quantity both of alkali and chlorine to be used on any
kind of tissue can be readily ascertained from time to time, by those skilled in the
art, by samples drawn from the testing pipes; the violent expulsion from the
testing pipes producing similar disintegrating effects upon the sample examined, as
are produced in the entire mass when finally expelled; and showing clearly when